rexresearch.com
Naomi HALAS, et al.
Nanoparticle Solar Steam
1. David Brown : Making
steam without boiling water, thanks to nanoparticles
2. Jade Boyd : Off-grid sterilization with Rice
U.’s ‘solar steam’
3. Jade Boyd : Rice unveils super-efficient
solar-energy technology
4. Oara Neumann, et al. : Solar Vapor Generation
Enabled by Nanoparticles
5. YouTube : Researchers create solar steam using
nanoparticles at Rice University
6. Zheyu Fang, et al. : Evolution of Light-Induced
Vapor Generation at a Liquid-Immersed Metallic Nanoparticle
7. YouTube : Solar-Powered Steam Generation --
Solar steam used to clean human waste in the developing world
8. Oara Neumann, et al, : Compact solar autoclave
based on steam generation using broadband light-harvesting
nanoparticles
9. Patents
http://www.washingtonpost.com/national/health-science/making-steam-without-boiling-water-thanks-to-nanoparticles/2012/11/19/3d98c4d6-3264-11e2-9cfa-e41bac906cc9_story.html
Making steam without boiling water,
thanks to nanoparticles
By David Brown
It is possible to create steam within seconds by focusing sunlight
on nanoparticles mixed into water, according to new research.
That observation, reported Monday by scientists at Rice University
in Texas, suggests myriad applications in places that lack
electricity or burnable fuels. A sun-powered boiler could
desalinate sea water, distill alcohol, sterilize medical equipment
and perform other useful tasks.
"We can build a portable, compact steam generator that depends
only on sunlight for input. It is something that could really be
good in remote or resource-limited locations," said Naomi J.
Halas, an engineer and physicist at Rice who ran the experiment.
Whether the rig she and her colleagues describe would work on an
industrial scale is unknown. If it does, it could mark an advance
for solar-powered energy more generally.
"We will see how far it can ultimately go. There are certainly
places and situations where it would be valuable to generate
steam," said Paul S. Weiss, editor of the American Chemical
Society's journal ACS Nano, which published the paper online in
advance of the journalís December print publication.
The experiment is more evidence that nanoscale devices -- in this
case, beads one-tenth the diameter of a human hair -- behave in
ways different from bigger objects.
In the apparatus designed by the Rice team, steam forms in a
vessel of water long before the water becomes warm to the touch.
It is, in effect, possible to turn a container of water into steam
before it gets hot enough to boil.
"There is a disconnect between what happens when we heat a pot of
water and what happens when we put nanoparticles in that water,"
said Weiss, who is a chemist and director of the California
Nanosystems Institute at UCLA.
"This is a novel proposed application of nanoparticles," said A.
Paul Alivisatos, director of the Lawrence Berkeley National
Laboratory and a nanotechnology expert. ìI think it is very
interesting and will stimulate a lot of others to think about the
heating of water with sunlight."
In the Rice experiment, the researchers stirred a small amount of
nanoparticles into water and put the mixture into a glass vessel.
They then focused sunlight on the mixture with a lens.
The nanoparticles -- either carbon or gold-coated silicon dioxide
beads -- have a diameter shorter than the wavelength of visible
light. That allows them to absorb most of a wave of light's
energy. If they had been larger, the particles would have
scattered much of the light.
In the focused light, a nanoparticle rapidly becomes hot enough to
vaporize the layer of water around it. It then becomes enveloped
in a bubble of steam. That, in turn, insulates it from the mass of
water that, an instant before the steam formed, was bathing and
cooling it.
Insulated in that fashion, the particle heats up further and forms
more steam. It eventually becomes buoyant enough to rise. As it
floats toward the surface, it hits and merges with other bubbles.
At the surface, the nanoparticles-in-bubbles release their steam
into the air. They then sink back toward the bottom of the vessel.
When they encounter the focused light, the process begins again.
All of this occurs within seconds.
In all, about 80 percent of the light energy a nanoparticle
absorbs goes into making steam, and only 20 percent is "lost" in
heating the water. This is far different from creating steam in a
tea kettle. There, all the water must reach boiling temperature
before an appreciable number of water molecules fly into the air
as steam.
The phenomenon is such that it is possible to put the vessel
containing the water-and-nanoparticle soup into an ice bath, focus
light on it and make steam.
"It shows you could make steam in an arctic environment," Halas
said. "There might be some interesting applications there."
The apparatus can also separate mixtures of water and other
substances into their components -- the process known as
distillation -- more completely than is usually possible. For
example, with normal distillation of a water-and-alcohol mixture,
it isn't possible to get more than 95 percent pure alcohol. Using
nanoparticles to create the steam, 99 percent alcohol can be
collected.
Halas said the nanoparticles are not expensive to make and,
because they act essentially as catalysts, are not used up. A
nanoparticle steam generator could be used over and over. And, as
James Watt and other 18th-century inventors showed, if you can
generate steam easily, you can create an industrial revolution.
The research is being funded in part by the Bill & Melinda
Gates Foundation in the hope it might prove useful to developing
countries. Halas and her team recently spent three days in Seattle
demonstrating the apparatus.
"Luckily," she said, "it was sunny."
The solar steam device developed at Rice University has an
overall energy efficiency of 24 percent, far surpassing that
of photovoltaic solar panels.
It may first be used in sanitation and water-purification
applications in the developing world. Photo by Jeff Fitlow
... But how
to deal with residual solids fouling the system ?
Hunh ? Eh ? Riddle me that ...
http://news.rice.edu/2013/07/22/off-grid-sterilization-with-rice-u-s-solar-steam-2/
July 22, 2013
Off-grid sterilization with Rice U.’s
‘solar steam’
by
Jade Boyd
Solar-powered sterilization technology supported by Gates
Foundation
Rice University nanotechnology researchers have unveiled a
solar-powered sterilization system that could be a boon for more
than 2.5 billion people who lack adequate sanitation. The “solar
steam” sterilization system uses nanomaterials to convert as much
as 80 percent of the energy in sunlight into germ-killing heat.
The technology is described online in a July 8 paper in the
Proceedings of the National Academy of Sciences Early Edition. In
the paper, researchers from Rice’s Laboratory for Nanophotonics
(LANP) show two ways that solar steam can be used for
sterilization — one setup to clean medical instruments and another
to sanitize human waste.
“Sanitation and sterilization are enormous obstacles without
reliable electricity,” said Rice photonics pioneer Naomi Halas,
the director of LANP and lead researcher on the project, with
senior co-author and Rice professor Peter Nordlander. “Solar
steam’s efficiency at converting sunlight directly into steam
opens up new possibilities for off-grid sterilization that simply
aren’t available today.”
In a previous study last year, Halas and colleagues showed that
“solar steam” was so effective at direct conversion of solar
energy into heat that it could even produce steam from ice water.
“It makes steam directly from sunlight,” she said. “That means the
steam forms immediately, even before the water boils.”
Halas, Rice’s Stanley C. Moore Professor in Electrical and
Computer Engineering, professor of physics, professor of chemistry
and professor of biomedical engineering, is one of the world’s
most-cited chemists. Her lab specializes in creating and studying
light-activated particles. One of her creations, gold nanoshells,
is the subject of several clinical trials for cancer treatment.
Oara Neumann and Naomi Halas -- Rice University graduate student
Oara Neumann, left, and scientist Naomi Halas are co-authors of a
new study about a highly efficient method of turning sunlight into
heat. They expect their technology to have an initial impact as an
ultra-small-scale system to treat human waste in developing
nations without sewer systems or electricity. Photo by Jeff Fitlow
Solar steam’s efficiency comes from light-harvesting nanoparticles
that were created at LANP by Rice graduate student Oara Neumann,
the lead author on the PNAS study. Neumann created a version of
nanoshells that converts a broad spectrum of sunlight — including
both visible and invisible bandwidths — directly into heat. When
submerged in water and exposed to sunlight, the particles heat up
so quickly they instantly vaporize water and create steam. The
technology has an overall energy efficiency of 24 percent.
Photovoltaic solar panels, by comparison, typically have an
overall energy efficiency of around 15 percent.
When used in the autoclaves in the tests, the heat and pressure
created by the steam were sufficient to kill not just living
microbes but also spores and viruses. The solar steam autoclave
was designed by Rice undergraduates at Rice’s Oshman Engineering
Design Kitchen and refined by Neumann and colleagues at LANP. In
the PNAS study, standard tests for sterilization showed the solar
steam autoclave could kill even the most heat-resistant microbes.
“The process is very efficient,” Neumann said. “For the Bill &
Melinda Gates Foundation program that is sponsoring us, we needed
to create a system that could handle the waste of a family of four
with just two treatments per week, and the autoclave setup we
reported in this paper can do that.”
Halas said her team hopes to work with waste-treatment pioneer
Sanivation to conduct the first field tests of the solar steam
waste sterilizer at three sites in Kenya.
“Sanitation technology isn’t glamorous, but it’s a matter of life
and death for 2.5 billion people,” Halas said. “For this to really
work, you need a technology that can be completely off-grid,
that’s not that large, that functions relatively quickly, is easy
to handle and doesn’t have dangerous components. Our Solar Steam
system has all of that, and it’s the only technology we’ve seen
that can completely sterilize waste. I can’t wait to see how it
performs in the field.”
Paper co-authors include Curtis Feronti, Albert Neumann, Anjie
Dong, Kevin Schell, Benjamin Lu, Eric Kim, Mary Quinn, Shea
Thompson, Nathaniel Grady, Maria Oden and Nordlander, all of Rice.
The research was supported by a Grand Challenges grant from the
Bill & Melinda Gates Foundation and by the Welch Foundation.
Rice University graduate student Oara Neumann, left, and
scientist Naomi Halas are co-authors of a new study about a
highly efficient method of turning sunlight into heat. They
expect their technology to have an initial impact as an
ultra-small-scale system to treat human waste in developing
nations without sewer systems or electricity. Photo by Jeff
Fitlow -
http://news.rice.edu/2012/11/19/rice-unveils-super-efficient-solar-energy-technology-2/
November 19, 2012
Rice unveils super-efficient
solar-energy technology
by
Jade Boyd
‘Solar steam’ so effective it can make steam from icy cold
water
Rice University scientists have unveiled a revolutionary new
technology that uses nanoparticles to convert solar energy
directly into steam. The new “solar steam” method from Rice’s
Laboratory for Nanophotonics (LANP) is so effective it can even
produce steam from icy cold water.
Details of the solar steam method were published online today in
ACS Nano. The technology has an overall energy efficiency of 24
percent. Photovoltaic solar panels, by comparison, typically have
an overall energy efficiency around 15 percent. However, the
inventors of solar steam said they expect the first uses of the
new technology will not be for electricity generation but rather
for sanitation and water purification in developing countries.
Rice University graduate student Oara Neumann, left, and scientist
Naomi Halas are co-authors of new research on a highly efficient
method of turning sunlight into heat. They expect their technology
to have an initial impact as an ultra-small-scale system to treat
human waste in developing nations without sewer systems or
electricity. Photo by Jeff Fitlow
“This is about a lot more than electricity,” said LANP Director
Naomi Halas, the lead scientist on the project. “With this
technology, we are beginning to think about solar thermal power in
a completely different way.”
The efficiency of solar steam is due to the light-capturing
nanoparticles that convert sunlight into heat. When submerged in
water and exposed to sunlight, the particles heat up so quickly
they instantly vaporize water and create steam. Halas said the
solar steam’s overall energy efficiency can probably be increased
as the technology is refined.
“We’re going from heating water on the macro scale to heating it
at the nanoscale,” Halas said. “Our particles are very small —
even smaller than a wavelength of light — which means they have an
extremely small surface area to dissipate heat. This intense
heating allows us to generate steam locally, right at the surface
of the particle, and the idea of generating steam locally is
really counterintuitive.”
To show just how counterintuitive, Rice graduate student Oara
Neumann videotaped a solar steam demonstration in which a test
tube of water containing light-activated nanoparticles was
submerged into a bath of ice water. Using a lens to concentrate
sunlight onto the near-freezing mixture in the tube, Neumann
showed she could create steam from nearly frozen water.
Steam is one of the world’s most-used industrial fluids. About 90
percent of electricity is produced from steam, and steam is also
used to sterilize medical waste and surgical instruments, to
prepare food and to purify water.
Most industrial steam is produced in large boilers, and Halas said
solar steam’s efficiency could allow steam to become economical on
a much smaller scale.
People in developing countries will be among the first to see the
benefits of solar steam. Rice engineering undergraduates have
already created a solar steam-powered autoclave that’s capable of
sterilizing medical and dental instruments at clinics that lack
electricity. Halas also won a Grand Challenges grant from the Bill
and Melinda Gates Foundation to create an ultra-small-scale system
for treating human waste in areas without sewer systems or
electricity.
“Solar steam is remarkable because of its efficiency,” said
Neumann, the lead co-author on the paper. “It does not require
acres of mirrors or solar panels. In fact, the footprint can be
very small. For example, the light window in our demonstration
autoclave was just a few square centimeters.”
Another potential use could be in powering hybrid air-conditioning
and heating systems that run off of sunlight during the day and
electricity at night. Halas, Neumann and colleagues have also
conducted distillation experiments and found that solar steam is
about two-and-a-half times more efficient than existing
distillation columns.
Halas, the Stanley C. Moore Professor in Electrical and Computer
Engineering, professor of physics, professor of chemistry and
professor of biomedical engineering, is one of the world’s
most-cited chemists. Her lab specializes in creating and studying
light-activated particles. One of her creations, gold nanoshells,
is the subject of several clinical trials for cancer treatment.
For the cancer treatment technology and many other applications,
Halas’ team chooses particles that interact with just a few
wavelengths of light. For the solar steam project, Halas and
Neumann set out to design a particle that would interact with the
widest possible spectrum of sunlight energy. Their new
nanoparticles are activated by both visible sunlight and shorter
wavelengths that humans cannot see.
“We’re not changing any of the laws of thermodynamics,” Halas
said. “We’re just boiling water in a radically different way.”
Paper co-authors include Jared Day, graduate student; Alexander
Urban, postdoctoral researcher; Surbhi Lal, research scientist and
LANP executive director; and Peter Nordlander, professor of
physics and astronomy and of electrical and computer engineering.
The research was supported by the Welch Foundation and the Bill
and Melinda Gates Foundation.
ACS Nano, 2013, 7 (1), pp 42–49
DOI: 10.1021/nn304948h
November 19, 2012
Solar Vapor Generation Enabled by
Nanoparticles
Oara Neumann, Alexander S. Urban, Jared Day, Surbhi Lal,
Peter Nordlander, and Naomi J. Halas
Solar illumination of broadly absorbing metal or carbon
nanoparticles dispersed in a liquid produces vapor without the
requirement of heating the fluid volume. When particles are
dispersed in water at ambient temperature, energy is directed
primarily to vaporization of water into steam, with a much smaller
fraction resulting in heating of the fluid. Sunlight-illuminated
particles can also drive H2O–ethanol distillation, yielding
fractions significantly richer in ethanol content than simple
thermal distillation. These phenomena can also enable important
compact solar applications such as sterilization of waste and
surgical instruments in resource-poor locations.
https://www.youtube.com/watch?v=ved0K5CtmsU
Nov 19, 2012
Researchers create solar steam using
nanoparticles at Rice University
Rice University scientists have unveiled a revolutionary new
technology that uses nanoparticles to convert solar energy
directly into steam. The new "solar steam" method from Rice's
Laboratory for Nanophotonics is so effective it can even produce
steam from icy cold water. Details of the solar steam method were
published online today in ACS Nano. The technology's inventors
said they expect it will first be used in sanitation and
water-purification applications in the developing world.
http://pubs.acs.org/doi/abs/10.1021/nl4003238
Nano Lett. 2013, 13, 1736-1742
Evolution of Light-Induced Vapor
Generation at a Liquid-Immersed Metallic Nanoparticle.
Zheyu Fang, Yu-rong Zhen, Oara Neumann, Albert
Polman, F. Javier Garcia de Abajo, Peter Nordlander, and Naomi
J. Halas.
When an Au nanoparticle in a liquid medium is illuminated with
resonant light of sufficient intensity, a nanometer scale envelope
of vapor—a “nanobubble”—surrounding the particle, is formed. This
is the nanoscale onset of the well-known process of liquid
boiling, occurring at a single nanoparticle nucleation site,
resulting from the photothermal response of the nanoparticle. Here
we examine bubble formation at an individual metallic nanoparticle
in detail. Incipient nanobubble formation is observed by
monitoring the plasmon resonance shift of an individual,
illuminated Au nanoparticle, when its local environment changes
from liquid to vapor. The temperature on the nanoparticle surface
is monitored during this process, where a dramatic temperature
jump is observed as the nanoscale vapor layer thermally decouples
the nanoparticle from the surrounding liquid. By increasing the
intensity of the incident light or decreasing the interparticle
separation, we observe the formation of micrometer-sized bubbles
resulting from the coalescence of nanoparticle-“bound” vapor
envelopes. These studies provide the first direct and quantitative
analysis of the evolution of light-induced steam generation by
nanoparticles from the nanoscale to the macroscale, a process that
is of fundamental interest for a growing number of applications.
https://www.youtube.com/watch?v=J2DbVQ6AnDs
Jul 22, 2013
Solar-Powered Steam Generation --
Solar steam used to clean human waste in the developing
world
Researchers at Rice University's Laboratory for Nanophotonics
(LANP) have unveiled a solar-powered sterilization system that
could be a boon for more than 2.5 billion people who lack adequate
sanitation. LANP's "solar steam" sterilization system converts as
much as 80 percent of the energy in sunlight into germ-killing
heat that can be used for off-grid sterilization. In a July 8
study in the Proceedings of the National Academy of Sciences, LANP
researchers showed they could use the technology to sterilize
human waste, an application that could improve public health in
areas that lack reliable electric power.
http://www.pnas.org/content/110/29/11677.full?sid=1c7d56d7-0281-4ddb-9edc-76e1713a91a7
PNAS 2013 110 (29) 11677-11681
Compact solar autoclave based on steam
generation using broadband light-harvesting nanoparticles
Oara Neumann, Curtis Feronti, Albert D. Neumann, Anjie Dong,
Kevin Schell, Benjamin Lu, Eric Kim, Mary Quinn, Shea
Thompson, Nathaniel Grady, Peter Nordlander, Maria Oden, and
Naomi Halas
Abstract
The lack of readily available sterilization processes for medicine
and dentistry practices in the developing world is a major risk
factor for the propagation of disease. Modern medical facilities
in the developed world often use autoclave systems to sterilize
medical instruments and equipment and process waste that could
contain harmful contagions. Here, we show the use of broadband
light-absorbing nanoparticles as solar photothermal heaters, which
generate high-temperature steam for a standalone, efficient solar
autoclave useful for sanitation of instruments or materials in
resource-limited, remote locations. Sterilization was verified
using a standard Geobacillus stearothermophilus-based biological
indicator.
According to the World Health Organization, healthcare-associated
infections are the most prevalent adverse consequence of medical
treatment worldwide (1⇓–3). Although this problem is disconcerting
and costly in developed countries, its impact in developing
regions is devastating (4). More than one-quarter of the human
population worldwide lacks access to electricity, let alone the
high power requirements necessary for modern sterilization
systems. Because more than one-half of all people in developing
regions lack access to all-weather roads, the channeling of a
consistent supply of disposable sterilizing resources into these
areas presents an even more daunting challenge (5). Consequently,
addressing the problem of resource-constrained sterilization can
be viewed as an effort to provide solutions to both power and
supply chain constraints.
The underlying cause of healthcare-associated (nosocomial)
infections is prolonged or focused exposure to unsanitary
conditions. Such conditions can be ameliorated through the use of
sanitation and sterilization methods. Sterilization involves the
destruction of all microorganisms and their spores, whereas
disinfection is a less robust process that involves the removal of
microorganisms without complete sterilization (6). One of the
simplest, most effective, and most reliable approaches for the
sterilization of medical devices and materials is the use of an
autoclave. The fundamental concept of an autoclave is to expose
the media to be sterilized to saturated steam at an elevated
temperature. On coming into contact with the medium to be
sterilized, the saturated steam condenses from the gas phase to
the liquid phase, transferring its latent heat of vaporization to
the material to be sterilized and thus, any associated microbes on
its surface. Such a rapid transfer of heat is extremely effective
for denaturing proteins and may be used to destroy most known
types of infectious agents, including bacteria, viruses, or viral
spores.
Steam-based autoclave systems neutralize potentially infectious
microorganisms localized on solid surfaces or in liquid-phase
media by exposing them to high-temperature pressurized steam. The
process of steam sterilization relies on both steam temperature
and time duration of steam exposure to ensure irreversible
destruction of all microorganisms, especially bacterial
endospores, which are considered particularly thermally stable.
Although steam-based sterilization is the primary method of choice
for the processing of medical waste in the developed world, the
large energy requirement for operation is the fundamental
limitation for its adoption in developing countries, with limited
or nonexistent access to sources of electricity sufficient to
power such systems.
Recently, we reported the use of broadband light-absorbing
particles for solar steam generation (7). A variety of
nanoparticles such as metallic nanoshells, nanoshell aggregates,
and conductive carbon nanoparticles, when dispersed in aqueous
solution and illuminated by sunlight, has been shown to convert
absorbed solar energy to steam at an efficiency of just over 80%,
where less than 20% of the energy contributes to heating the
liquid volume (7). This effect depends on the highly localized,
strong photothermal response of these types of nanoparticles, a
characteristic that is being used to effectively ablate solid
tumors by irradiation with near-IR laser light with near-unity
tumor remission rates (8⇓⇓⇓⇓⇓⇓⇓–16). In the solar steam generation
process, broadband light-absorbing nanoparticles create a large
number of nucleation sites for steam generation within the fluid.
As light is absorbed by a nanoparticle, a temperature difference
between the nanoparticle and the surrounding fluid is established
because of a reduced thermal conductivity at the metal–liquid
interface: this local temperature increase may become sufficient
to transform the liquid in the direct vicinity of the nanoparticle
into vapor. On sustained illumination, the vapor envelope
surrounding the nanoparticle grows, eventually resulting in
buoyancy of the nanoparticle–bubble complex. When this complex
reaches the surface of the liquid, the vapor is released,
resulting in vigorous nonequilibrium steam generation that does
not require the bulk fluid temperature to have reached its boiling
point. If the fluid is kept in an ice bath, steam is produced,
even when the fluid temperature remains at 0 °C (7). Over
prolonged exposure to sunlight, however, both the more-efficient
process of nanoparticle-based steam generation and the
less-efficient process of bulk fluid heating occur, eventually
resulting in simultaneous nanoparticle-based steam generation and
boiling of the bulk fluid. The combination of these two processes
results in solar steam production that occurs at higher steam
temperatures than can be achieved using nonparticle-based fluid
heating (Fig. 1). The nanoparticles are neither dispersed into the
vapor phase nor degraded by the steam generation process.
Fig. 1.
Temperature evolution of solar steam generation. (A)
Temperature vs. time for Au nanoshell-dispersed water (i,
liquid; ii, vapor) and water without nanoparticles (iii, liquid;
iv, vapor) under solar exposure. (Au nanoparticle concentration
sufficient to produce an optical density of unity.) (B)
Photograph of system used in the temperature evolution of solar
steam generation: (a) transparent vessel isolated with a vacuum
jacket to reduce thermal losses, (b) two thermocouples for
sensing the solution and the steam temperature, (c) pressure
sensor, and (d) 1/16-in nozzle.
The temperature–time evolution of the nanoparticle-dispersed fluid
and steam produced during solar irradiation is shown in Fig. 1A
with and without the presence of nanoparticles. A detailed
characterization of the nanoparticles is shown in Fig. S1. With
nanoparticle dispersants, temperatures of both the liquid and the
steam increase far more rapidly than the temperature of pure water
(Fig. 1A, i and ii), with the liquid water reaching 100 °C more
rapidly with nanoparticle dispersants than water without
nanoparticles. Measurable steam production occurs at a lower water
temperature for the case with nanoparticle dispersants, because
nanoparticle-dispersed steam generation can occur at any fluid
temperature. For the case shown here, measurable steam production
appears at a water temperature of ∼70 °C, well below the steam
production threshold for pure water. Perhaps most importantly,
however, is the large difference in steady-state temperature
achieved for the two systems: with the inclusion of nanoparticle
dispersants, the temperature of both the water and the vapor
increase well above the standard boiling point of water. In this
case, an equilibrium temperature of 140 °C is easily achieved in
the nanoparticle-dispersed water–steam system. This elevated
temperature enables the use of nanoparticle-generated solar steam
for medical sterilization applications.
The evolution of solar steam generation from Au nanoshells
dispersed in water was quantified in an open-loop system (Fig. 1B)
consisting of a 200-mL vessel isolated with a vacuum jacket to
prevent heat loss, a pressure sensor, and two thermocouples to
monitor both the liquid and vapor temperatures. The vessel was
illuminated with solar radiation focused by a 0.69-m2 Fresnel lens
into the glass vessel containing 100 mL nanoparticles at a
concentration of 1010 particles/m3 or alternatively, water with no
nanoparticles as a control. On solar illumination, vapor was
allowed to escape through a 16-µm-diameter nozzle, while the
pressure and temperature were recorded.
Here, we show two different compact solar autoclaves driven by
nanoparticle-based solar steam generation that are well-suited to
off-grid applications. Using a solar concentrator (Fresnel lens or
dish mirror) to deliver sunlight into the nanoparticle-dispersed
aqueous working fluid, this process is capable of delivering steam
at a temperature of 115–135 °C into a 14.2-L volume for a time
period sufficient for sterilization. Sterilization was verified
using a standard Geobacillus stearothermophilus-based biological
indicator.
Experimental Section
Two solar sterilization designs have been developed. One is a
portable, closed-loop solar autoclave system suitable for
sterilization of medical or dental tools; the second design is a
solar dish collector autoclave system that can serve as a
standalone, off-grid steam source suitable for human or animal
waste sterilization systems or other applications. Steam from the
closed-loop system (Fig. 2A) is produced under solar illumination,
transported into the sterilization volume, condensed, and then
delivered back into the fluid vessel. The design consists of three
main subsystems: the steam generation module (Fig. 2A, I), the
connection module (Fig. 2A, II), and the sterilization module
(Fig. 2A, III). More detailed schematics of the system are
presented in Figs. S1, S2, and S3.
Fig. 2.
(A) Schematic and photograph of the closed-loop solar autoclave
showing (I) the steam generation module, (II) the connection
module, and (III) the sterilization module. The components of
the system are (a) sterilization vessel, (b) pressure sensor,
(c) thermocouple sensor, (d) relief valve, (e and f) control
valves, (g) solar collector containing the nanoparticle-based
heater solution, (h) check valve, and (k) solar concentrator (a
plastic Fresnel lens of 0.67-m2 surface area). (B) Schematic and
photograph of the open-loop solar autoclave: the components of
the system are (i) solar concentrator (44-in dish mirror), (ii)
heat collector containing metallic nanoparticles, and (iii)
sterilization vessel that contains a pressure sensor, two
thermocouple sensors, a steam relief valve, and two hand pumps
and valves that control the input and output of waste. The solar
concentrator dish system has a dual tracking system powered by a
small car battery recharged by a solar cell unit.
The particle solution is contained in a custom-built insulated
glass vessel with two inlets that lead to the connection module.
Solar collection is accomplished with a relatively small and
inexpensive Fresnel lens. The hot solar steam generated within
this module is channeled out one nozzle of the connection module
into the sterilization module, where it condenses on the objects
to be sterilized, returning as condensate to the steam generation
module. A check valve at one port of the steam generation module
ensures a unidirectional flow of steam throughout the entire
system.
The sterilization module consists of an insulated pressure vessel
(a converted stovetop autoclave with a 14.2-L capacity). A
condensate return hole (diameter of 0.86 cm) was milled on the
bottom face of the autoclave vessel 10 cm away from the center.
Similarly, a steam inlet hole (diameter of 0.86 cm) was milled on
the lid of the sterilizing vessel 10 cm away from the center. A
finite element analysis (SolidWorks using the Tresca maximum) was
performed to identify the mechanically weakest portions of the
pressure vessel when placed under high-stress conditions (Fig.
S3). By varying the radial position of the hole in the base of the
pressure vessel, a minimum factor of safety (vessel material
strength/design load) under many different machining
configurations was determined. A 0.86-cm-diameter hole positioned
10 cm from the center of the pressure vessel was determined to be
the optimal location, with a minimum factor of safety of 3.35. To
minimize heat losses from the steam generation module and the
sterilization module, the system was insulated with a sealant
(Great Stuff Fireblock Insulating Foam Sealant) applied to the
surfaces of the vessels and covered with aluminum foil to further
minimize heat loss.
The connection module consists of two parts: the steam connection,
which allows steam to flow from the steam generation module to the
sterilization module, and the condensate connection, which returns
the condensate from the sterilization module (Fig. S3). The steam
connection consists of polytetrafluoroethylene (PTFE) tubing
insulated in fiberglass pipe wrap and a ball valve; the condensate
connection consists of a ball valve, PTFE tubing insulated in
fiberglass pipe wrap, a check valve, and a pressure release valve.
Both units contain an adaptor to connect to the steam generation
module.
The solar-generated steam enters the sterilization module at the
top of the vessel, forcing the unsterile air down and out of the
vessel through the air exhaust tube, which is connected to the
control valve. Trapped unsterile air can have an insulating effect
and prevent complete sterilization; therefore, it is critical that
as much air as possible be removed from the sterilization module.
After the unsterile air is purged from the system, the control
valve is closed to allow pressure to build up in the vessel. The
cycle is maintained at a minimum of 115 °C and 12 psig and a
maximum of 140 °C and 20 psig in all regions of the sterilization
module throughout the duration of a sterilization cycle. The
condensate is channeled back to the steam generation module by a
check valve when the hydrostatic pressure exceeds the maximum
pressure of the valve (rated at 0.3 psi).
An optimized, open-loop, prototypical compact solar autoclave for
human waste sterilization is presented in Fig. 2B. Using a 44-in
solar dish collector to focus sunlight into the
nanoparticle-dispersed aqueous working fluid, we deliver steam
into a 14.2-L capacity sterilization volume (a commercially
available stovetop autoclave). This volume could easily
accommodate the 10-L capacity volume of a mobile sanitation
(moSAN) toilet, for example (a personal-use toilet designed for
Deutsche Gesellschaft für Internationale Zusammenarbeit GmbH and
originally developed for the urban poor in Bangladesh), and if
operated three times per week, it could process the weekly amount
of both solid and liquid waste produced by a household of four
adults (∼35 L). Solar energy is supplied to this unit through a
reflective parabolic dish that tracks the sun, is powered by a
small car battery, and is rechargeable with a small solar panel.
The generated steam is transmitted to the autoclave through
silicon tubing. Unprocessed waste is delivered to the autoclave by
means of a mechanical hand pump, which can be easily operated by a
single person. After the sterilization process, the sanitized
waste is removed by gravity. Because of its simple, modular
design, the system can easily be expanded to provide
high-temperature steam for larger-scale applications.
The nanoparticle solution is contained in a custom-designed
vacuum-insulated vessel positioned at the focus of the parabolic
reflector. The steam generated within this module is channeled
into the waste sterilization module. Under typical operation, the
steam temperature is maintained at 132 °C for 5 min, the duration
of time required for an International Organization for
Standardization (ISO) standard sterilization cycle. The steam
temperature was monitored at the output of the steam generation
module, and the waste solution temperature was monitored inside
the sterilization module. These two locations are expected to
reach the sterilization temperature with slight thermal (gas and
liquid phases) differences inside the sterilization module during
the sterilization process.
The steam temperature was monitored in both geometries at the
steam connection and the condensate connection directly adjacent
to the sterilization module. These two locations are expected to
have the highest and lowest steam temperatures, respectively,
allowing us to measure the overall temperature gradient generated
inside the sterilization module during the sterilization process.
The steam temperature before and during a sterilization cycle is
shown in
Fig. 3.
The autoclave temperature distribution of the (A) closed-loop
and (B) open-loop solar autoclaves. The temperature of steam vs.
time measured in two different locations in autoclave: top (red
curve) and respective bottom (blue curve). The dashed line
indicates temperature required for sterilization, and the red
box indicates the sterilization regime (115 °C for 20 min or 132
°C for 4.6 min). The ambient temperature (green) was monitored
as reference.
The red curve in Fig. 3 is the temperature of the steam at the
inlet valve to the sterilization vessel, the blue curve in Fig. 3
is the temperature of the condensate at the sterilization vessel
output, and the ambient temperature in Fig. 3 is the green curve.
The dashed gray line in Fig. 3 represents the temperature required
for sterilization (115–132 °C). In the case of the closed-loop
system (Fig. 3A), the irregular spikes in the temperature curves
correspond to when the steam begins to enter the vessel. The
bottom thermocouple shows two major spikes during warm-up that are
generated by the release of unsterilized air from the
sterilization module. The first spike induced turbulence into the
system, which exposed the thermocouple briefly to hotter steam.
The second jump in the temperature data of the output thermocouple
corresponds to the release of the remaining unsterilized insulated
air. The monitoring data clearly show that the autoclave is easily
capable of maintaining a temperature over 115 °C for more than 30
min of the sterilization time required at that temperature. In the
case of the open-loop system (Fig. 3B), the red curve is the gas
temperature of the steam measured at the vessel inlet valve, the
blue curve is the temperature inside the vessel contents
(artificial fecal material), and the ambient temperature is the
green curve. The dashed gray line represents the desired
temperature required for sterilization (132 °C). After an initial
ramp-up period of ∼20 min, the sterilization temperature is
reached, and the temperature–time curve continues to oscillate
around this value because of the frequent release of steam from
the sterilization vessel through the pressure safety valve. The
solar thermal evolution data show that the autoclave is capable of
maintaining a temperature around 132 °C for more than 5 min.
To test whether our systems can achieve the Sterility Assurance
Level defined by the Food and Drug Administration (17), we
operated the system through a cycle with the sterilization vessel
containing commercial biological indicator strips for G.
stearothermophilus (EZTest Self-Contained Biological Indicator
Strips; SGM Biotech), a reference strain commonly used for
sterilization testing. The test strips were secured in the
sterilization module near the inlet stream and outlet stream taps
or immersed in a fecal simulator solution. After completion of the
cycle, the strips were incubated for 36 h at 55–60 °C. The results
are shown in Fig. 4.
Fig. 4.
Biological indicators used to test solar autoclave
sterilization. Test vials of G. stearothermophilus placed in
various locations in the sterilization module: (A) the
top/bottom of vessels were sealed for solid material and
unprocessed control and (B) placed in fecal stimulant sealed for
liquid–solid material and unprocessed control. They were used to
test solar autoclave sterilization. The sterilization is
confirmed by color change of vial contents.
The color change shown by the vials in Fig. 4, relative to the
control vial, indicates that sterilization is achieved by
operating the solar autoclave through one 30-min cycle at 115 °C
for the closed-loop system and one 5-min cycle at 132 °C for the
open-loop system. If some spores survive a sterilization cycle,
the biological indicator culture medium undergoes a color change
from purple to yellow. The observed color change indicates that
spore survival did not occur.
In conclusion, we have shown two compact solar autoclaves enabled
by solar steam generation using broadband, light-absorbing
nanoparticles. The systems maintain temperatures between 115 °C
and 132 °C for the time period sufficient to sterilize the
contents of a 14.2-L volume, which is in accordance with Food and
Drug Administration sterilization requirements. Using a parabolic
dish solar collector enables a faster heat-up time and higher
operating temperatures, which shorten the sterilization cycle time
significantly (from 15 min at 121 °C to 5 min at 132 °C). The
nanoparticles are not consumed by the heating process and can be
reused indefinitely; the only consumable is water, which need not
be sterilized before use. This type of system can easily be
expanded to provide direct steam generation for additional
applications, which may include distillation-based water
purification, cooking, waste remediation, or electricity
generation.
Figs. S1, S2, and S3 show extensive schematics of the
configuration system and characterizations of metallic
nanostructures.
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PATENTS
WO2014127345
SOLAR STEAM PROCESSING OF BIOFUEL FEEDSTOCK AND SOLAR
DISTILLATION OF BIOFUELS
A method of producing bioethanol that includes receiving a
feedstock solution that includes polysaccharides in a vessel
comprising a complex is described. The complex may be copper
nanoparticles, copper oxide nanoparticles, nanoshells, nanorods,
carbon moieties, encapsulated nanoshells, encapsulated
nanoparticles, and/or branched nanostructures. The method also
includes applying electromagnetic (EM) radiation to the complex
such that the complex absorbs the EM radiation to generate heat.
Using the heat generated by the complex, sugar molecules may be
extracted from the polysaccharides in the feedstock solution, and
fermented. Then, bioethanol may be extracted from the vessel.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. § 119(e)
to U.S. Provisional Patent Application Serial Nos. 61/765,992 and
61/775,751, which are incorporated by reference in their entirety.
BACKGROUND
[0002] The production of bioethanol from cellulosic feedstock,
such as switchgrass, may require that the feedstock be processed
such that the fermentable carbohydrates and sugars are released
from the initial material. This is an intensive processing step
that currently requires the input of energy in the form of heat,
the use of caustic chemicals to break down plant cell walls, or
the use of enzymes for that purpose, all of which add cost to the
final product, currently rendering it noncompetitive with respect
to fossil-derived fuels.
SUMMARY
[0003] In general, in one aspect, the invention relates to a
method of producing bioethanol that includes receiving a feedstock
solution that includes polysaccharides in a vessel comprising a
complex. The complex may be copper nanoparticles, copper oxide
nanoparticles, nanoshells, nanorods, carbon moieties, encapsulated
nanoshells, encapsulated nanoparticles, and/or branched
nanostructures. The method also includes applying electromagnetic
(EM) radiation to the complex such that the complex absorbs the EM
radiation to generate heat. Using the heat generated by the
complex, sugar molecules may be extracted from the polysaccharides
in the feedstock solution, and fermented. Then, bioethanol may be
extracted from the vessel.
[0004] In general, in one aspect, the invention relates to a
system for producing bioethanol that includes a vessel with a
complex. The vessel is configured to receive a feedstock solution
that includes polysaccharides in a vessel comprising a complex.
The complex may be copper nanoparticles, copper oxide
nanoparticles, nanoshells, nanorods, carbon moieties, encapsulated
nanoshells, encapsulated nanoparticles, and/or branched
nanostructures. The method also includes applying electromagnetic
(EM) radiation to the complex such that the complex absorbs the EM
radiation to generate heat. Using the heat generated by the
complex, sugar molecules may be extracted from the polysaccharides
in the feedstock solution, and fermented. Then, bioethanol may be
extracted from the vessel.
BRIEF DESCRIPTION OF DRAWINGS
[0005] FIG. 1 shows a schematic of a complex in accordance
with one or more embodiments of the invention.
[0006] FIG. 2 shows a flow chart in accordance with one or
more embodiments of the invention.
[0007] FIG. 3 shows a chart of the absorbance in accordance
with one or more embodiments of the invention.
[0008] FIGS. 4A- B show charts of an energy dispersive
x-ray spectroscopy
(EDS) measurement in accordance with one or more
embodiments of the invention.
[0009] FIG. 5 shows a chart of the absorbance in accordance
with one or more embodiments of the invention.
[0010] FIG. 6 shows a chart of an EDS measurement in
accordance with one or more embodiments of the invention. [0011]
FIG. 7 shows a chart of the absorbance in accordance with one or
more embodiments of the invention.
[0012] FIG. 8 shows a flow chart in accordance with one or
more embodiments of the invention.
[0013] FIG. 9 shows a chart of the absorbance in accordance
with one or more embodiments of the invention.
[0014] FIG. 10 shows a chart of an EDS measurement in
accordance with one or more embodiments of the invention.
[0015] FIGS. 1 lA-11C show charts of the porosity of gold
corral structures in accordance with one or more embodiments of
the invention.
[0016] FIGS. 12A-12C show charts of the mass loss of water
into steam in accordance with one or more embodiments of the
invention.
[0017] FIGS. 13A-13B show charts of the energy capture
efficiency in accordance with one or more embodiments of the
invention.
[0018] FIG. 14 shows a system in accordance with one or
more embodiments of the invention.
[0019] FIG. 15 shows a flowchart for a method of producing
bioethanol in accordance with one or more embodiments of the
invention.
[0020] FIG. 16 shows an example system for producing
bioethanol in accordance with one or more embodiments of the
invention.
[0021] FIG. 17 shows an example of a system in accordance
with one or more embodiments of the invention.
[0022] FIG. 18 shows an example of a system in accordance
with one or more embodiments of the invention.
[0023] FIGS. 19A and 19B show the temperature and pressure
as a function of time in accordance with one or more embodiments
of the invention. [0024] FIG. 20 shows an amount of D-Glucose
and D-Galactose extracted in accordance with one or more
embodiments of the invention.
DETAILED DESCRIPTION
[0025] Specific embodiments of the invention will now be described
in detail with reference to the accompanying figures. Like
elements in the various figures are denoted by like reference
numerals for consistency.
[0026] In the following detailed description of embodiments of the
invention, numerous specific details are set forth in order to
provide a more thorough understanding of the invention. However,
it will be apparent to one of ordinary skill in the art that the
invention may be practiced without these specific details. In
other instances, well-known features have not been described in
detail to avoid unnecessarily complicating the description.
[0027] In general, embodiments of the invention relate to the
production of bioethanol using a steam generation process, where
the steam is generated using nanoparticles.
[0028] The solar steam production using nanonparticles as
described, for example, in U.S. Application No. 13/326,482, U.S.
Patent Application No. 13/514,762, and PCT Application No.
US2011/062497, the contents of which are hereby incorporated by
reference in their entirety, along with multiple applications
thereof, may be used to process cellulosic feedstock either as
steam or as a high pressure, high temperature liquid. In one or
more embodiments of the invention, the application of solar steam
may reduce the energy cost for processing the cellulosic
feedstock. Moreover, the processing method for extraction of
fermentable biomass may be also take advantage of this essentially
free source of high temperature/high pressure steam using our
earlier disclosed methods. The solar steam source may be adapted
to provide both elevated temperatures and pressures as needed for
a liquid water batch extractor. [0029] In accordance with one or
more embodiments of the invention, a second important processing
step for biofuels, most specifically bioethanol, is distillation
of the fermented extract to produce ethanol of the appropriate H2O
concentration, for a particular application, such as for use in
vehicles. In one or more embodiments of the invention,
nanoparticle-enabled solar steam generation may be performed on
mixtures of liquids for distillation purposes. In these
embodiments, the method may produce a richer ethanol distillate
than normal thermal heating methods, which may simplify and
streamline the final distillation step in bioethanol production.
[0030] In accordance with embodiments of the invention, bioethanol
production from lignocellulosic biomass such as hay or straw may
be used to generate fuel. Alfalfa and Coastal Bermudagrass are
known non-food feeds. A pretreatment of the feedstock prior to
fermentation is crucial in order to achieve a high ethanol yield.
The cell walls of grass contain cellulose and hemicellulose. These
polysaccharides need to be degraded into smaller units which are
accessible to yeast to perform fermentation.
[0031] In one or more embodiments of the invention,
nanoparticle-generated solar steam may be used for the hot water
pretreatment of feedstock. If the solar steam is kept in a closed
system, high temperature and a significant pressure builds up. The
conditions that embodiments of the invention may reach are
sufficient for the pretreatment process. A slurry of the feedstock
in water is kept in a pretreatment module where the steam streams
into so the temperature and pressure rises to a regime where the
polysaccharides degrade into smaller units. This improves the
fermentability of the raw material and will lead to higher ethanol
yield.
[0032] Embodiments of the invention use complexes (e.g.,
nanoshells) that have absorbed EM radiation to produce the energy
used to generate the heated fluid. The invention may provide for a
complex mixed in a liquid solution, used to coat a wall of a
vessel, integrated with a material of which a vessel is made,
and/or otherwise suitably integrated with a vessel used to apply
EM radiation to the complex. All the piping and associated
fittings, pumps, valves, gauges, and other equipment described,
used, or contemplated herein, either actually or as one of
ordinary skill in the art would conceive, are made of materials
resistant to the heat and/or fluid and/or vapor transported,
transformed, pressurized, created, or otherwise handled within
those materials.
[0033] A source of EM radiation may be any source capable of
emitting energy at one or more wavelengths. For example, EM
radiation may be any source that emits radiation in the
ultraviolet, visible, and infrared regions of the electromagnetic
spectrum. A source of EM radiation may be manmade or occur
naturally. Examples of a source of EM radiation may include, but
are not limited to, the sun, waste heat from an industrial
process, and a light bulb. One or more concentrators may be used
to intensify and/or concentrate the energy emitted by a source of
EM radiation. Examples of a concentrator include, but are not
limited to, lens(es), a parabolic trough(s), mirror(s), black
paint, or any combination thereof.
[0034] Embodiments of this invention may be used in any
residential, commercial, and/or industrial application where
heating of a fluid may be needed. Examples of such applications
include, but are not limited to, alcohol production (e.g.,
ethanol, methanol) as for a biofuels plant, chemical treatment,
chemicals and allied products, (e.g., rubber, plastics, textile
production), laboratories, perfumeries, air products (e.g., argon,
hydrogen, oxygen), drug manufacturing, and alcoholic beverages.
[0035] In one or more embodiments, the complex may include one or
more nanoparticle structures including, but not limited to,
nanoshells, coated nanoshells, metal colloids, nanorods, branched
or coral structures, and/or carbon moieties. In one or more
embodiments, the complex may include a mixture of nanoparticle
structures to absorb EM radiation. Specifically, the complex may
be designed to maximize the absorption of the electromagnetic
radiation emitted from the sun. Further, each complex may absorb
EM radiation over a specific range of wavelengths.
[0036] In one or more embodiments, the complex may include metal
nanoshells. A nanoshell is a substantially spherical dielectric
core surrounded by a thin metallic shell. The plasmon resonance of
a nanoshell may be determined by the size of the core relative to
the thickness of the metallic shell. Nanoshells may be fabricated
according to U.S. Patent 6,685,986, hereby incorporated by
reference in its entirety. The relative size of the dielectric
core and metallic shell, as well as the optical properties of the
core, shell, and medium, determines the plasmon resonance of a
nanoshell. Accordingly, the overall size of the nanoshell is
dependent on the absorption wavelength desired. Metal nanoshells
may be designed to absorb or scatter light throughout the visible
and infrared regions of the electromagnetic spectrum. For example,
a plasmon resonance in the near infrared region of the spectrum
(700nm-900 nm) may have a substantially spherical silica core
having a diameter between 90nm-175 nm and a gold metallic layer
between 4 nm-35nm.
[0037] A complex may also include other core-shell structures, for
example, a metallic core with one or more dielectric and/or
metallic layers using the same or different metals. For example, a
complex may include a gold or silver nanoparticle, spherical or
rod-like, coated with a dielectric layer and further coated with
another gold or silver layer. A complex may also include other
core-shell structures, for example hollow metallic shell
nanoparticles and/or multi-layer shells.
[0038] In one or more embodiments, a complex may include a
nanoshell encapsulated with a dielectric or rare earth element
oxide. For example, gold nanoshells may be coated with an
additional shell layer made from silica, titanium or europium
oxide.
[0039] In one embodiment of the invention, the complexes may be
aggregated or otherwise combined to create aggregates. In such
cases, the resulting aggregates may include complexes of the same
type or complexes of different types.
[0040] In one embodiment of the invention, complexes of different
types may be combined as aggregates, in solution, or embedded on
substrate. By combining various types of complexes, a broad range
of the EM spectrum may be absorbed.
[0041] FIG. 1 is a schematic of a nanoshell coated with an
additional rare earth element oxide in accordance with one or more
embodiments of the invention. Typically, a gold nanoshell has a
silica core 102 surrounded by a thin gold layer 104. As stated
previously, the size of the gold layer is relative to the size of
the core and determines the plasmon resonance of the particle.
According to one or more embodiments of the invention, a nanoshell
may then be coated with a dielectric or rare earth layer 106. The
additional layer 106 may serve to preserve the resultant plasmon
resonance and protect the particle from any temperature effects,
for example, melting of the gold layer 104.
[0042] FIG. 2 is a flow chart of a method of manufacturing the
coated nanoshells in accordance with one or more embodiments of
the invention. In ST 200, nanoshells are manufactured according to
known techniques. In the example of europium oxide, in ST 202, 20
mL of a nanoshell solution may be mixed with 10 mL of 2.5M
(NH2)2CO and 20 mL of 0.1M of Eu(N03)3xH20 solutions in a glass
container. In ST 204, the mixture may be heated to boiling for 3-5
minutes under vigorous stirring. The time the mixture is heated
may determine the thickness of the additional layer, and may also
determine the number of nanoparticle aggregates in solution. The
formation of nanostructure aggregates is known to create
additional plasmon resonances at wavelengths higher than the
individual nanostructure that may contribute to the energy
absorbed by the nanostructure for heat generation. In ST 206, the
reaction may then be stopped by immersing the glass container in
an ice bath. In ST 208, the solution may then be cleaned by
centrifugation, and then redispersed into the desired solvent. The
additional layer may contribute to the solubility of the
nanoparticles in different solvents. Solvents that may be used in
one or more embodiments of the invention include, but are not
limited to, water, ammonia, ethylene glycol, and glycerin.
[0043] In addition to europium, other examples of element oxides
that may be used in the above recipe include, but are not limited
to, erbium, samarium, praseodymium, and dysprosium. The additional
layer is not limited to rare earth oxides. Any coating of the
particle that may result in a higher melting point, better
solubility in a particular solvent, better deposition onto a
particular substrate, and/or control over the number of aggregates
or plasmon resonance of the particle may be used. Examples of the
other coatings that may be used, but are not limited to silica,
titanium dioxide, polymer-based coatings, additional layers formed
by metals or metal alloys, and/or combinations of materials.
[0044] FIG. 3 is an absorbance spectrum of three nanoparticle
structures that may be included in a complex in accordance with
one or more embodiments disclosed herein. In FIG. 3, a gold
nanoshell spectrum 308 may be engineered by selecting the core and
shell dimensions to obtain a plasmon resonance peak at -800 nm.
FIG. 3 also includes a Eu2O3-encapsulated gold nanoshell spectrum
310, where the Eu2O3-encapsulated gold nanoshell is manufactured
using the same nanoshells from the nanoshell spectrum 308. As may
be seen in FIG 3, there may be some particle aggregation in the
addition of the europium oxide layer. However, the degree of
particle aggregation may be controlled by varying the reaction
time described above. FIG. 3 also includes a -100 nm diameter
spherical gold colloid spectrum 312 that may be used to absorb
electromagnetic radiation in a different region of the
electromagnetic spectrum. In the specific examples of FIG. 3, the
Eu2O3-encapsulated gold nanoshells may be mixed with the gold
colloids to construct a complex that absorbs any EM radiation from
500 nm to greater than 1200 nm. The concentrations of the
different nanoparticle structures may be manipulated to achieve
the desired absorption of the complex.
[0045] X-ray photoelectron spectroscopy (XPS) and/or energy
dispersive x- ray spectroscopy (EDS) measurements may be used to
investigate the chemical composition and purity of the
nanoparticle structures in the complex. For example, FIG. 4 A
shows an XPS spectrum in accordance with one or more embodiments
of the invention. XPS measurements were acquired with a PHI
Quantera X-ray photoelectron spectrometer. FIG. 4A shows the XPS
spectra in different spectral regions corresponding to the
elements of the nanoshell encapsulated with europium oxide. FIG.
4A shows the XPS spectra display the binding energies for Eu (3d
5/2) at 1130 eV 414, Eu (2d 3/2) at 1160eV 416, Au (4f 7/2) at
83.6 eV 418, and Au (4f 5/2) at 87.3 eV 420 of nanoshells
encapsulated with europium oxide. For comparison, FIG. 4B shows an
XPS spectrum of europium oxide colloids that may be manufactured
according to methods known in the art. FIG. 4B shows the XPS
spectra display the binding energies for Eu (3d 5/2) at 1130 eV
422 and Eu (2d 3/2) at 1160eV 424 of europium oxide colloids.
[0046] In one or more embodiments of the invention, the complex
may include solid metallic nanoparticles encapsulated with an
additional layer as described above. For example, using the
methods described above, solid metallic nanoparticles may be
encapsulated using silica, titanium, europium, erbium, samarium,
praseodymium, and dysprosium. Examples of solid metallic
nanoparticles include, but are not limited to, spherical gold,
silver, copper, or nickel nanoparticles or solid metallic
nanorods. The specific metal may be chosen based on the plasmon
resonance, or absorption, of the nanoparticle when encapsulated.
The encapsulating elements may be chosen based on chemical
compatibility, the encapsulating elements ability to increase the
melting point of the encapsulated nanoparticle structure, and the
collective plasmon resonance, or absorption, of a solution of the
encapsulated nanostructure, or the plasmon resonance of the
collection of encapsulated nanostructures when deposited on a
substrate.
[0047] In one or more embodiments, the complex may also include
copper colloids. Copper colloids may be synthesized using a
solution-phase chemical reduction method. For example, 50 mL of
0.4 M aqueous solution of L- ascorbic acid, 0.8M of Polyvinyl
pyridine (PVP), and 0.01M of copper (II) nitride may be mixed and
heated to 70 degree Celsius until the solution color changes from
a blue-green color to a red color. The color change indicates the
formation of copper nanoparticles. FIG. 5 is an experimental and
theoretical spectrum in accordance with one or more embodiments of
the invention. FIG. 5 includes an experimental absorption spectrum
526 of copper colloids in accordance with one or more embodiments
of the invention. Therefore, copper colloids may be used to absorb
electromagnetic radiation in the 550 nm to 900 nm range.
[0048] FIG. 5 also includes a theoretical absorption spectrum 528
calculated using Mie scattering theory. In one or more
embodiments, Mie scattering theory may be used to theoretically
determine the absorbance of one or more nanoparticle structures to
calculate and predict the overall absorbance of the complex. Thus,
the complex may be designed to maximize the absorbance of solar
electromagnetic radiation.
[0049] Referring to FIG. 6, an EDS spectrum of copper colloids in
accordance with one or more embodiments of the invention is shown.
The EDS spectrum of the copper colloids confirms the existence of
copper atoms by the appearance peaks 630. During the EDS
measurements, the particles are deposited on a silicon substrate,
as evidenced by the presence of the silicon peak 632.
[0050] In one or more embodiments, the complex may include copper
oxide nanoparticles. Copper oxide nanostructures may be
synthesized by 20 mL aqueous solution of 62.5mM Cu(NO3)2being
directly mixed with 12 mL NH4OH under stirring. The mixture may
be stirred vigorously at approximately 80°C for 3 hours, then
the temperature is reduced to 40°C and the solution is stirred
overnight. The solution color turns from blue to black color
indicating the formation of the copper oxide nanostructure. The
copper oxide nanostructures may then be washed and re-suspended
in water via centrifugation. FIG. 7 shows the absorption of
copper oxide nanoparticles in accordance with one or more
embodiments of the invention. The absorption of the copper oxide
nanoparticles 734 may be used to absorb electromagnetic radiation
in the region from -900 nm to beyond 1200 nm. In one or more
embodiments of the invention, the complex may include branched
nanostructures. One of ordinary skill in the art will appreciate
that embodiments of the invention are not limited to strict gold
branched structures. For example, silver, nickel, copper, or
platinum branched structures may also be used. FIG. 8 is a flow
chart of the method of manufacturing gold branched structures in
accordance with one or more embodiments of the invention. In ST
800, an aqueous solution of 1% HAuCl4may be aged for two-three
weeks. In ST 802, a polyvinyl pyridine (PVP) solution may be
prepared by dissolving 0.25 g in approximately 20 mL ethanol
solution and rescaled with water to a final volume of 50mL. In ST
804, 50 mL of the 1% HAuCl4and 50 mL of the PVP solution may be
directly mixed with 50 mL aqueous solution of 0.4M L-ascorbic acid
under stirring. The solution color may turn immediately in dark
blue-black color which indicates the formation of a gold
nanoflower or nano-coral. Then, in ST 806, the Au nanostructures
may then be washed and resuspended in water via centrifugation. In
other words, the gold branched nanostructures may be synthesized
through L-ascorbic acid reduction of aqueous chloroaurate ions at
room temperature with addition of PVP as the capping agent. The
capping polymer PVP may stabilize the gold branched nanostructures
by preventing them from aggregating. In addition, the gold
branched nanostructures may form a porous polymer-type matrix.
[0052] FIG. 9 shows the absorption of a solution of gold branched
nanostructures in accordance with one or more embodiments of the
invention. As can be seen in FIG. 9, the absorption spectrum 936
of the gold branched nanostructures is almost flat for a large
spectral range, which may lead to considerably high photon
absorption. The breadth of the spectrum 936 of the gold branched
nanostructures may be due to the structural diversity of the gold
branched nanostructures or, in other works, the collective effects
of which may come as an average of individual branches of the gold
branched/corals nanostructure.
[0053] FIG. 10 shows the EDS measurements of the gold branched
nanostructures in accordance with one or more embodiments of the
invention. The EDS measurements may be performed to investigate
the chemical composition and purity of the gold branched
nanostructures. In addition, the peaks 1038 in the EDS
measurements of gold branched nanostructures confirm the presence
of Au atoms in the gold branched nanostructures.
[0054] FIG. 11 shows a Brunauer-Emmett-Teller (BET) surface area
and pore size distribution analysis of branches in accordance with
one or more embodiments of the invention. The BET surface area and
pore size may be performed to characterize the branched
nanostructures. FIG. 11A presents the nitrogen
adsorption-desorption isotherms of a gold corral sample calcinated
at 150 C for 8 hours. The isotherms may exhibit a type IV isotherm
with a N2hysteresis loops in desorption branch as shown. As shown
in FIG. 11 A, the isotherms may be relatively flat in the
low-pressure region (P/P0< 0.7). Also, the adsorption and
desorption isotherms may be completely superposed, a fact which
may demonstrate that the adsorption of the samples mostly likely
occurs in the pores. At the relative high pressure region, the
isotherms may form a loop due to the capillarity agglomeration
phenomena. FIG. 11B presents a bimodal pore size distribution,
showing the first peak 1140 at the pore diameter of 2.9 nm and the
second peak 1142 at 6.5 nm. FIG. 11C shows the BET plots of gold
branched nanostructures in accordance with one or more embodiments
of the invention. A value of 10.84 m /g was calculated for the
specific surface area of branches in this example by using a
multipoint BET-equation.
[0055] In one or more embodiments of the invention, the gold
branched nanostructures dispersed in water may increase the
nucleation sites for boiling, absorb electromagnetic energy,
decrease the bubble lifetime due to high surface temperature and
high porosity, and increase the interfacial turbulence by the
water gradient temperature and the Brownian motion of the
particles. The efficiency of a gold branched complex solution may
be high because it may allow the entire fluid to be involved in
the boiling process.
[0056] As demonstrated in the above figures and text, in
accordance with one or more embodiments of the invention, the
complex may include a number of different specific nanostructures
chosen to maximize the absorption of the complex in a desired
region of the electromagnetic spectrum. In addition, the complex
may be suspended in different solvents, for example water or
ethylene glycol. Also, the complex may be deposited onto a surface
according to known techniques. For example, a molecular or polymer
linker may be used to fix the complex to a surface, while allowing
a solvent to be heated when exposed to the complex. The complex
may also be embedded in a matrix or porous material. For example,
the complex may be embedded in a polymer or porous matrix material
formed to be inserted into a particular embodiment as described
below. For example, the complex could be formed into a removable
cartridge. As another example, a porous medium (e.g., fiberglass)
may be embedded with the complex and placed in the interior of a
vessel containing a fluid to be heated. The complex may also be
formed into shapes in one or more embodiments described below in
order to maximize the surface of the complex and, thus, maximize
the absorption of EM radiation. In addition, the complex may be
embedded in a packed column or coated onto rods inserted into one
or more embodiments described below. [0057] FIGS. 12A-12C show
charts of the mass loss and temperature increase of different
nanostructures that may be used in a complex in accordance with
one or more embodiments of the invention. The results shown in
FIGS. 12A- 12C were performed to monitor the mass loss of an
aqueous nanostructure solution for 10 minutes under sunlight (FIG.
12B) versus non-pulsed diode laser illumination at 808 nm (FIG.
12A). In FIG. 12A, the mass loss versus time of the laser
illumination at 808 nm is shown for Eu203-coated nanoshells 1244,
non-coated gold nanoshells 1246, and gold nanoparticles with a
diameter of -100 nm 1248. Under laser exposure, as may be expected
from the absorbance shown in FIG. 3, at 808 nm illumination, the
coated and non-coated nanoshells exhibit a mass loss due to the
absorbance of the incident electromagnetic radiation at 808 nm. In
addition, as the absorbance is lower at 808 nm, the 100 nm
diameter gold colloid exhibits little mass loss at 808 nm
illumination. In Figure 12 A, the Au nanoparticles demonstrated a
lower loss rate that was nearly the same as water because the
laser wavelength was detuned from plasmon resonance frequency. The
greatest mass loss was obtained by adding a layer around the gold
nanoshells, where the particle absorption spectrum was
approximately the same as the solar spectrum (see FIG 3.)
[0058] In FIG, 12B, the mass loss as a function of time under
exposure to the sun in accordance with one or more embodiments of
the invention is shown. In FIG. 12B, the mass loss under sun
exposure with an average power of 20 W is shown for Eu2O3-coated
nanoshells 1250, non-coated gold nanoshells 1252, gold
nanoparticles with a diameter of - 100 nm 1254, and a water
control 1256. As in the previous example, the greatest mass loss
may be obtained by adding a rare earth or dielectric layer around
a nanoshell.
[0059] The resulting mass loss curves in FIGS. 12A and 12B show
significant water evaporation rates for Eu2O3-coated gold
nanoshells. The mass loss may be slightly greater under solar
radiation because the particles were able to absorb light from a
broader range of wavelengths. In addition, the collective effect
of aggregates broadens the absorption spectrum of the oxide-coated
nanoparticles, which may help to further amplify the heating
effect and create local areas of high temperature, or local hot
spots. Aggregates may also allow a significant increase in boiling
rates due to collective self organizing forces. The oxide layer
may further enhance steam generation by increasing the surface
area of the nanoparticle, thus providing more boiling nucleation
sites per particle, while conserving the light-absorbing
properties of the nanostructure.
[0060] FIG. 12C shows the temperature increase versus time under
the 808 nm laser exposure in accordance with one or more
embodiments of the invention. In FIG. 12C, the temperature
increase under the 808 nm laser exposure is shown for Eu2O3-coated
nanoshells 1258, non-coated gold nanoshells 1260, gold
nanoparticles with a diameter of -100 nm 1262, and a water control
1264. As may be expected, the temperature of the solutions of the
different nanostructures that may be included in the complex
increases due to the absorption of the incident electromagnetic
radiation of the specific nanostructure and the conversion of the
absorbed electromagnetic radiation in to heat.
[0061] FIG. 13 A is a chart of the solar trapping efficiency in
accordance with one or more embodiments of the invention. To
quantify the energy trapping efficiency of the complex, steam is
generated in a flask and throttled through a symmetric
convergent-divergent nozzle. The steam is then cooled and
collected into an ice bath maintained at 0°C. The nozzle serves to
isolate the high pressure in the boiler from the low pressure in
the ice bath and may stabilize the steam flow. Accordingly, the
steam is allowed to maintain a steady dynamic state for data
acquisition purposes. In FIG. 13 A, the solar energy capture
efficiency (η) of water (i) and Eu203 -coated nanoshells (ii) and
gold branched (ii) nanostructures is shown. The resulting thermal
efficiency of steam formation may be estimated at 80% for the
coated nanoshell complex and 95% for a gold branched complex. By
comparison, water has approximately 10% efficiency under the same
conditions.
[0062] In one or more embodiments of the invention, the
concentration of the complex may be modified to maximize the
efficiency of the system. For example, in the case where the
complex is in solution, the concentration of the different
nanostructures that make up the complex for absorbing EM radiation
may be modified to optimize the absorption and, thus, optimize the
overall efficiency of the system. In the case where the complex is
deposited on a surface, the surface coverage may be modified
accordingly.
[0063] In FIG. 13B, the steam generation efficiency versus gold
nanoshell concentration for solar and electrical heating in
accordance with one or more embodiments of the invention is shown.
The results show an enhancement in efficiency for both electrical
1366 and solar 1368 heating sources, confirming that the bubble
nucleation rate increases with the concentration of complex. At
high concentrations, the complex is likely to form small
aggregates with small inter-structure gaps. These gaps may create
"hot spots", where the intensity of the electric field may be
greatly enhanced, causing an increase in temperature of the
surrounding water. The absorption enhancement under electrical
energy 1366 is not as dramatic as that under solar power 1368
because the solar spectrum includes energetic photons in the NIR,
visible and UV that are not present in the electric heater
spectrum. At the higher concentrations, the steam generation
efficiency begins to stabilize, indicating a saturation behavior.
This may result from a shielding effect by the particles at the
outermost regions of the flask, which may serve as a virtual
blackbody around the particles in the bulk solution.
[0064] FIG. 14 shows a system in accordance with one or more
embodiments of the invention. The bioethanol producing system 1400
demonstrated in FIG. 14 includes a bioethanol extracting system
1420. The bioethanol extracting system 1420 includes a vessel 1424
and concentrator 1422. The EM radiation source 1414 supplies the
radiation to the concentrator 1422 to provide the energy to
produce the bioethanol from the feedstock. The bioethanol
producing system 1400 also includes a feedstock supply system 1450
that includes a feedstock source 1452 and pump 1454. The feedstock
supply system 1450 may mix the feedstock into with a solution
prior to pumping the feedstock solution into the vessel 1424. The
bioethanol producing system 1400 may optionally include a water
heater 1412 to preheat the feedstock solution in accordance with
one or more embodiments of the invention. The bioethanol producing
system 1400 may also include an optional condenser 1440 for
collecting the bioethanol produced.
[0065] In one or more embodiments of the invention, each EM
radiation source (e.g., EM radiation source 1414) is any other
natural and/or manmade source capable of emitting one or more
wavelengths of energy. The EM radiation source may also be a
suitable combination of sources of EM radiation, whether emitting
energy using the same wavelengths or different wavelengths.
[0066] Optionally, in one or more embodiments of the invention,
each EM radiation concentrator (e.g., EM radiation concentrator
1422) is a device used to intensify the energy emitted by an EM
radiation source. Examples of an EM radiation concentrator
include, but are not limited to, one or more lenses (e.g., Fresnel
lens, biconvex, negative meniscus, simple lenses, complex lenses),
a parabolic trough, black paint, one or more disks, an array of
multiple elements (e.g., lenses, disks), or any suitable
combination thereof. An EM radiation concentrator may be used to
increase the rate at which the EM radiation is absorbed by the
complex.
[0067] In one or more embodiments of the invention, a vessel
(e.g., vessel 1 1424) holds the feedstock solution and facilitates
the transfer of energy (e.g., heat) to the feedstock solution to
extract sugars present in the polysaccharides of the feedstock
solution. A vessel may be designed and configured to operate under
a pressure.
[0068] A vessel (e.g., vessel 1 1424), or a portion thereof, may
include the complex. For example, a vessel may include a liquid
solution (e.g., the feedstock, water, some other material, liquid
or otherwise, such as ethylene glycol or glycine) that includes
the complex, be coated on one or more inside surfaces with a
coating of the complex, be coated on one or more outside surfaces
with a coating of the complex, include a porous matrix into which
the complex is embedded, include a packed column that includes
packed, therein, a substrate on which the complex is attached,
include rods or similar objects coated with the complex and
submerged in the liquid solution, be constructed of a material
that includes the complex, or any combination thereof. A vessel
may also be adapted to facilitate one or more EM radiation
concentrators (not shown), as described above.
[0069] A vessel may be of any size, material, shape, color, degree
of translucence/transparency, or any other characteristic suitable
for the operating temperatures and pressures to produce the amount
and concentration of bioethanol. For example, a vessel may be a
large, stainless steel cylindrical tank holding a quantity of
solution that includes the complex and with a number of lenses
(acting as EM radiation concentrators) along the lid and upper
walls. In such a case, the solution may include the feedstock to
be heated to extract the sugars from the feedstock and/or vaporize
(distill) the bioethanol. Further, in such a case, the feedstock
solution may include properties such that the complex remains in
the solution when a filtering system (described below) is used.
Alternatively, a chemical vessel may be a translucent pipe with
the interior surfaces coated (either evenly or unevenly) with a
substrate of the complex, where the pipe is positioned at the
focal point of a parabolic trough (acting as an EM radiation
concentrator) made of reflective metal.
[0070] Optionally, in one or more embodiments of the invention, a
bioethanol extracting system 1420 may include one or more
temperature gauges (not shown) to measure a temperature at
different points inside a vessel and/or at other components of the
bioethanol producing system 1400. For example, a temperature gauge
may be placed at the point in a vessel where a vapor element exits
the vessel (e.g., a vapor collector). Such temperature gauge may
be operatively connected to a control system (not shown) used to
control the amount and/or quality of vapor element produced in
heating the feedstock solution. In one or more embodiments of the
invention, a vessel may be pressurized where the pressure is read
and/or controlled using a pressure gauge (not shown). Those
skilled in the art will appreciate one or more control systems
used to create heated fluid in heating the cool fluid may involve
a number of devices, including but not limited to the temperature
gauges, pressure gauges, pumps, agitators, fans, and valves,
controlled (manually and/or automatically) according to a number
of protocols and operating procedures. In one or more embodiments
of the invention, the control system may be configured to maintain
a maximum temperature (or range of temperatures) of a vessel so
that the chemical mixture maintains (or does not exceed) a
predetermined temperature.
[0071] Optionally, in one or more embodiments of the invention,
one or more of the components of the bioethanol producing system
1400 may also include a filtering system (not shown). For example,
a filtering system may be located inside a vessel and/or at some
point before the chemical mixture enters the vessel. The filtering
system may capture impurities (e.g., dirt and other solids) in the
feedstock solution that may not be useful or that may inhibit the
bioethanol production process. The filtering system may vary,
depending on a number of factors, including but not limited to the
configuration of the vessel, the configuration of the chemical
mixture source, and the purity requirements of a vapor element.
The filtering system may be integrated with a control system. For
example, the filtering system may operate within a temperature
range measured by one or more temperature gauges.
[0072] Optionally, in one or more embodiments of the invention,
one or more pumps may be used in the bioethanol producing system
1400. A pump 1454 may be used to regulate the flow of the
feedstock solution from the feedstock solution source 1452 into a
vessel 1424 and/or the flow of the fluid element from a condenser
(e.g., condenser 1 1440). A pump may operate manually or
automatically (as with a control system, described above). Each
pump may operate using a variable speed motor or a fixed speed
motor. The flow of the feedstock solution, a vapor element from a
vessel, and/or a fluid element from a condenser may also be
controlled by gravity, a fan, pressure differential, some other
suitable mechanism, or any combination thereof.
[0073] Optionally, in one or more embodiments of the invention, a
storage tank of may be configured to store one or more fluid
elements and/or vapor elements after the vapor element has been
extracted from a vessel. In some embodiments of the invention, the
storage tank may be a vessel or a vapor collector.
[0074] Optionally, in one or more embodiments of the invention, a
supplemental water heater 1412 may be used in the bioethanol
producing system 1400 to preheat the feedstock solution, or the
solution used to make the feedstock solution.
[0075] FIG. 15 shows a flowchart for a method for producing
bioethanol in accordance with one or more embodiments of the
invention. While the various steps in this flowchart are presented
and described sequentially, one of ordinary skill will appreciate
that some or all of the steps may be executed in different orders,
may be combined or omitted, and some or all of the steps may be
executed in parallel. Further, in one or more of the embodiments
of the invention, one or more of the steps described below may be
omitted, repeated, and/or performed in a different order. In
addition, a person of ordinary skill in the art will appreciate
that additional steps, omitted in FIG. 15, may be included in
performing this method. Accordingly, the specific arrangement of
steps shown in FIG. 15 should not be construed as limiting the
scope of the invention.
[0076] One or more embodiments of the invention heat a feedstock
solution to extract one or more sugars of the feedstock solution.
The amount of feedstock solution that is heated by embodiments of
the invention may range from a few ounces to thousands of gallons
(or more) of feedstock solution.
[0077] Referring to FIG. 15, in Step 1502, EM radiation from an EM
radiation source is concentrated and sent to the steam generating
system. In Step 1504, the EM radiation irradiates a complex. The
complex absorbs the EM radiation and generates heat. The heat is
then used to heat a feedstock solution in Step 1506. The feedstock
solution may have impurities (e.g., other elements and/or
compounds) that are not needed or wanted when the fluid is in
vapor form. The vessel containing the fluid may be any container
capable of holding a volume of the fluid. For example, the vessel
may be a pipe, a chamber, or some other suitable container. In one
or more embodiments of the invention, the vessel is adapted to
maintain its characteristics (e.g., form, properties) under high
temperatures and pressures for extended periods of time. The
complex may be part of a solution inside the vessel, a coating on
the outside of the vessel, a coating on the inside of the vessel,
integrated as part of the material of which the vessel is made,
integrated with the vessel in some other way, or any suitable
combination thereof. The fluid may be received in the vessel using
a pump, a valve, a regulator, some other device to control the
flow of the fluid, or any suitable combination thereof.
[0078] In one or more embodiments of the invention, the EM
radiation is concentrated using an EM radiation concentrator, as
described above with respect to FIG. 14. For example, the EM
radiation may be concentrated using a lens or a parabolic trough.
In one or more embodiments of the invention, the EM radiation is
concentrated merely by exposing the vessel to the EM radiation.
[0079] In one or more embodiments of the invention, the complex
absorbs the EM radiation to generate heat. The EM radiation may be
applied to all or a portion of the complex located in the vessel.
The EM radiation may also be applied to an intermediary, which in
turn applies the EM radiation (either directly or indirectly, as
through convection) to the complex. A control system using, for
example, one or more temperature gauges, may regulate the amount
of EM radiation applied to the complex, thus controlling the
amount of heat generated by the complex at a given point in time.
Power required for any component in the control system may be
supplied by any of a number of external sources (e.g., a battery,
a photovoltaic solar array, alternating current power, direct
current power).
[0080] In Step 1508, sugar molecules are extracted from
polysaccharides in the feedstock solution. In one or more
embodiments of the invention, the heat generated by the complex is
used to heat the feedstock solution to extract the sugars. In Step
1510, the sugar molecules extracted from the feedstock solution
are fermented. The sugar molecules may be fermented using known
techniques, for example through the addition of saccharomyces
cerevisiae, a yeast. In Step 1512, the bioethanol is extracted. In
one or more embodiments of the invention, the bioethanol may be
extracted using the techniques described in PCT Application No.
US2011/062497. After completing Step 1510, the process may end.
[0081] Consider the following example, shown in FIG. 16, which
describes a system that produces steam used to heat the feedstock
solution in accordance with one or more embodiments described
above. This example is not intended to limit the scope of the
invention. Turning to the example, the EM radiation source 1614
irradiates the complex 1604 through the use of the concentrator
1610 as part of the complex based bioethanol extracting system
1620. In this specific embodiment, the concentrator 1610 is
parabolic mirror concentrating the EM radiation from the EM
radiation source 1614 to a vessel containing the complex 1604. The
complex based bioethanol extracting system 1620 may be used to
supply steam to the chamber 1636. The chamber 1636 may include a
temperature sensor 1632, a pressure sensor 1634, and a safety
valve 1660. The chamber may also optionally include a heater 1612.
[0082] In one or more embodiments of the invention, steam is
generated in the complex based bioethanol extracting system 1620.
One of ordinary skill will appreciate that the chamber 1636 may
include valves to isolate the chamber 1636 from the rest of the
apparatus for the insertion or removal of the feedstock in the
chamber 1636. At the conclusion of a cycle, a pump 1654 may be
used to recycle the fluid for the next cycle. Alternatively, the
pump 1654 may be used during the cycle to maintain the appropriate
temperature and pressure necessary for heating the feedstock.
[0083] FIG. 17 illustrates an alternative configuration of the
complex based bioethanol extracting system in accordance with one
or more embodiments of the invention. The system shown in FIG. 17
includes a chamber 1736 with a temperature sensor 1732, a pressure
sensor 1734, a supply valve 1770, and a safety valve 1760. The
supply valve 1770 may be used to supply or maintain the supply of
fluid in the chamber 1736. The complex 1704 may be disposed inside
the chamber 1736, with the complex being accessible to EM
radiation 1714, via the concentrator 1710. In one or more
embodiments of the invention, the concentrator may be a lens or
transparent material capable of handling the temperatures and
pressures necessary to extract the sugar molecules from the
feedstock within the chamber 1736. One or more embodiments of the
invention may include an optical system 1780 designed to direct
the EM radiation 1714 to the complex 1704, depending on the
relative position of the EM radiation source. In one or more
embodiments of the invention, such as that shown in FIG 17, the
system may be self-contained and portable. [0084] FIG. 18
illustrates a system for bioethanol extraction from feedstock in
accordance with one or more embodiments of the invention. The
system 1800 includes an EM radiation source 1814 that applies the
radiation, via a concentrator 1810, to a complex 1804 located
within the chamber 1836. The closed loop system 1800 may include
one or more temperature sensors 1832, pressure sensors 1834, and
safety valves 1860. The safety valves 1860 may open or close a
loop containing a condenser 1840. During operation, feedstock, or
feedstock solution, may be disposed inside the chamber 1836, at a
position so as not to impede the EM radiation from the EM
radiation source 1814 reaching the complex 1804. The EM radiation
from the EM radiation source 1814 is absorbed by complex 1804. As
a result of the irradiation, the complex 1804 generates heat in
the chamber 1836 and, thus, increases the temperature of the fluid
in the chamber 1836 and pressure in the chamber 1836. The fluid is
converted to steam and may be applied to the feedstock to extract
the sugar molecules and/or distill the bioethanol produced.
[0085] FIGs. 19A-19B illustrate the temperature and pressure that
may be achieved in accordance with one or more embodiments of the
invention. In FIG. 19 A, the complex is a gold branched structure
as described above in relation to FIGs. 8—11. The EM radiation
source is the sun. In FIG. 19A, the safety relief valve begins to
vent to the atmosphere when the solution inside the chamber
reaches ~170°C and the pressure reaches - 110 psi. In FIG. 19A,
the temperature of the solution 1901 as a function of time
indicates that the system may safely reach autoclave conditions.
FIG 19A also includes the temperature as a function of time before
1903 and after 1905 the condenser 1840. FIG. 19B is the pressure
1907 inside the chamber 1836 as a function of time. The
irregularity of the pressure and temperature curves shown in FIGs.
19A and 19B are a result of clouds momentarily obstructing the
sunlight which reduce the boiling intensity at different moments.
[0086] Embodiments of the claimed invention produce bioethanol
from lignocellulosic biomass to generate fuel. The cell walls of
grass contain cellulose and hemicellulose. These polysaccharides
are degraded into smaller units in accordance with embodiments of
the invention, which are accessible to yeast to perform
fermentation.
[0087] Cellulose consists of D-Glucose units linked via a β-1,4
glycosidic bond.
Hemicellulose contains Xylose, Mannose, Glucose and Galactose
units. Glucose and Galactose are sugars which can be fermented by
unmodified Saccharomyces cerevisiae, so their amount may be
maximized in the pretreatment hydrolyzate.
[0088] The theoretically available amount of sugar in the
feedstock may be deduced from a quantity of cellulose and
hemicellulose. The amounts of hemicellulose and cellulose as well
as other sugars available in feedstock are known. The amount of
Glucose and Galactose available in Coastal hay may exceed the
corresponding value for Alfalfa hay, which means Coastal may
provide a more promising feedstock.
[0089] A pretreatment with pressurized hot water may be used to
liberate sugars from polysaccharides. Referring to FIG. 20,
several experiments with different temperatures and pretreatment
times have been performed with a 5% w/v solid loading on a dry
matter basis in accordance with embodiments of the invention. A
Parr Instruments Model 4621 pressure vessel equipped with an
electrical heating unit was used to determine the values in FIG.
20. The loaded vessel was heated to a certain temperature, which
was kept constant for a defined time period. Thereafter the
pressure was released whereby the temperature of the contents
dropped rapidly. The sugar analysis of the pretreatment samples
shown in FIG. 20 was carried out with a HPLC system.
[0090] In accordance with one or more embodiments of the
invention, the temperature and pressure ranges shown in FIG. 19
may be used to liberate the sugars in a feedstock solution, as
demonstrated in FIG. 20. In one or more embodiments of the
invention, complex based distillation may be used to in the
extraction of bioethanol.
[0091] In one or more embodiments of the invention, the complex
based bioethanol production system may be a solar, portable
system. For example, the complex based bioethanol production
system may be used in the fields that provide the feedstock.
[0092] Embodiments of the invention may provide for bioethanol
production without the use of caustic chemicals to break down
plant cell walls, or the use of enzymes for that purpose.
Embodiments may also provide for more economical production of
bioethanol. Embodiments of the invention may provide an
alternative to fossil-derived fuels.
US2013334104
DISTILLING A CHEMICAL MIXTURE USING AN ELECTROMAGNETIC
RADIATION-ABSORBING COMPLEX FOR HEATING
A method of distilling a chemical mixture, the method including
receiving, in a vessel comprising a complex, the chemical mixture
comprising a plurality of fluid elements, applying electromagnetic
(EM) radiation to the complex, wherein the complex absorbs the EM
radiation to generate heat at a first temperature, transforming,
using the heat generated by the complex, a first fluid element of
the plurality of fluid elements of the chemical mixture to a first
vapor element, and extracting the first vapor element from the
vessel, where the complex is at least one selected from a group
consisting of copper nanoparticles, copper oxide nanoparticles,
nanoshells, nanorods, carbon moieties, encapsulated nanoshells,
encapsulated nanoparticles, and branched nanostructures.
US2013306463
PURIFYING A FLUID USING A HEAT CARRIER COMPRISING AN
ELECTROMAGNETIC RADIATION-ABSORBING COMPLEX
In general, the invention relates to a system. The system includes
a heating fluid vessel (1604) that includes first fluid and a
complex, where the complex receives electromagnetic (EM) radiation
(1602), and where the complex absorbs the EM radiation to generate
heat and where the heat increases a temperature of the first fluid
to generate a first heated fluid (1606). The system further
includes a heat exchanger (1608) adapted to receive the first
heated fluid (1606) and complex in a first chamber, receive a
mixture including a second fluid in a second chamber, and transfer
the heat from the first fluid from the complex to the mixture to
transform at least a portion of the target fluid of the mixture to
a target vapor. The system further includes a condenser (1632)
adapted to receive the target vapor, and condense the target vapor
to generate target fluid (1636).
US2012267893
ELECTRICITY GENERATION USING ELECTROMAGNETIC RADIATION
In general, in one aspect, the invention relates to a system to
create vapor for generating electric power. The system includes a
vessel comprising a fluid and a complex and a turbine. The vessel
of the system is configured to concentrate EM radiation received
from an EM radiation source. The vessel of the system is further
configured to apply the EM radiation to the complex, where the
complex absorbs the EM radiation to generate heat. The vessel of
the system is also configured to transform, using the heat
generated by the complex, the fluid to vapor. The vessel of the
system is further configured to sending the vapor to a turbine.
The turbine of the system is configured to receive, from the
vessel, the vapor used to generate the electric power.
US2012156102
WASTE REMEDIATION
A system including a steam generation system and a chamber. The
steam generation system includes a complex and the steam
generation system is configured to receive water, concentrate
electromagnetic (EM) radiation received from an EM radiation
source, apply the EM radiation to the complex, where the complex
absorbs the EM radiation to generate heat, and transform, using
the heat generated by the complex, the water to steam. The chamber
is configured to receive the steam and an object, wherein the
object is of medical waste, medical equipment, fabric, and fecal
matter.
US2012155841
GENERATING A HEATED FLUID USING AN ELECTROMAGNETIC
RADIATION-ABSORBING COMPLEX
A vessel including a concentrator configured to concentrate
electromagnetic (EM) radiation received from an EM radiation
source and a complex configured to absorb EM radiation to generate
heat. The vessel is configured to receive a cool fluid from the
cool fluid source, concentrate the EM radiation using the
concentrator, apply the EM radiation to the complex, and
transform, using the heat generated by the complex, the cool fluid
to the heated fluid. The complex is at least one of consisting of
copper nanoparticles, copper oxide nanoparticles, nanoshells,
nanorods, carbon moieties, encapsulated nanoshells, encapsulated
nanoparticles, and branched nanostructures. Further, the EM
radiation is at least one of EM radiation in an ultraviolet region
of an electromagnetic spectrum, in a visible region of the
electromagnetic spectrum, and in an infrared region of the
electromagnetic spectrum.
US9032731
COOLING SYSTEMS AND HYBRID A/C SYSTEMS USING AN
ELECTROMAGNETIC RADIATION-ABSORBING COMPLEX
A method for powering a cooling unit. The method
including applying electromagnetic (EM) radiation to a complex,
where the complex absorbs the EM radiation to generate heat,
transforming, using the heat generated by the complex, a fluid to
vapor, and sending the vapor from the vessel to a turbine coupled
to a generator by a shaft, where the vapor causes the turbine to
rotate, which turns the shaft and causes the generator to generate
the electric power, wherein the electric powers supplements the
power needed to power the cooling unit.
US7790066
Nanorice particles: hybrid plasmonic nanostructures
A new hybrid nanoparticle, i.e., a nanorice particle, which
combines the intense local fields of nanorods with the highly
tunable plasmon resonances of nanoshells, is described herein.
This geometry possesses far greater structural tunability than
previous nanoparticle geometries, along with much larger local
field enhancements and far greater sensitivity as a surface
plasmon resonance (SPR) nanosensor than presently known
dielectric-conductive material nanostructures. In an embodiment, a
nanoparticle comprises a prolate spheroid-shaped core having a
first aspect ratio. The nanoparticle also comprises at least one
conductive shell surrounding said prolate spheroid-shaped core.
The nanoparticle has a surface plasmon resonance sensitivity of at
least 600 nm RIU-1. Methods of making the disclosed nanorice
particles are also described herei
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