Scientists develop catalyst that cleans diesel emissions without platinum

 

Nanostellar has developed a mineral catalyst that outperforms platinum at a fraction of the cost

Diesel engines are a classic example of good news and bad news. The good news is that diesel engines are much more fuel efficient than petrol engines. The bad news is that they belch out some pretty nasty emissions like nitric oxide and nitrogen dioxide. The good news is that catalytic converters can scrub those out. The bad news is that last Friday the platinum needed by the converters is selling for US$1,473.10 an ounce. Now the good news is that a team at Nanostellar in Redwood, California, has developed a mineral catalyst that outperforms platinum at a fraction of the cost.
Platinum is an excellent catalyst, though it does have a few problems. One of the biggest at the moment is that a violent labor dispute in South Africa sent the price skyrocketing. Also, with the World Health Organization classifying diesel exhaust as a carcinogen, the potential demand for platinum for catalytic converters for hundred of millions of vehicles far outstrips supply. The Nanostellar team, led by Dr. Kyeongjae “K.J.” Cho, professor of materials science and engineering and physics at UT Dallas and co-founder of Nanostellar, determined that a mineral catalyst would be a cheaper alternative.

Dr. Kyeongjiae "K.J." Cho, professor of materials science and engineering and physics at UT Dallas (Photo: University of Texas at Dallas)

Reporting their findings in the August 17 issue of Science, Cho relates that computer modelling showed that mullite was a cost-effective substitute. Mullite is a silicate mineral discovered on the Isle of Mull, Scotland in 1924. It’s rare in nature, but a synthetic version is produced commercially for use in various porcelains, such as crucibles and heating balls. It has a very high melting point of 1840 C (3344 F) and as a mixed-phase oxide mineral it makes a very attractive catalyst. In addition, laboratory tests indicate that converters using mullite would have 45 percent lower emissions than with platinum.

Ideal and stepped crystal surface of Noxicat (Image: Geoffrey McCool)

“Our goal to move completely away from precious metals and replace them with oxides that can be seen commonly in the environment has been achieved,” Dr. Cho said. “We’ve found new possibilities to create renewable, clean energy technology by designing new functional materials without being limited by the supply of precious metals.”
The new catalyst, called Noxicat, will be developed for commercial use and further work is planned to determine its application in fuel cells.
Source: University of Texas at Dallas via Phys.org

Agri-Cube grows mass quantities of vegetables in a one-car parking spot

Bountiful harvest fills the trays of a Daiwa Agri-Cube prefab garden factory

Daiwa House, Japan's largest homebuilder, has introduced a line of prefabricated hydroponic vegetable factories, aimed at housing complexes, hotels, and top-end restaurants. Called the Agri-Cube, these units are touted by Daiwa as the first step in the industrialization of agriculture, to be located in and amongst the places where people live, work, and play.
More and more people desire sustainable, organic produce for their own use, and are turning to urban farming in an effort to insure the highest degree of freshness. However, some municipalities, neighborhoods, and homeowners associations have rules that effectively block such endeavors in areas under their sway. Add drought and pest control to the picture, and suddenly urban farming may seem more trouble than it is worth. There is a growing need for local supplies of freshly grown produce that avoids the difficulties presented by conventional small farms and gardens.

External view of the 11.7 square meter Agri-Cube E garden factory

This is where the Agri-Cube comes in. Measuring less than five meters (about 16 feet) in length and 2.5 meters (about 8 feet) wide, Daiwa's Agri-Cubes are smaller than a twenty-foot equivalent shipping container. An Agri-Cube can be brought to an installation site on the bed of a light heavy-duty truck. A concrete foundation about 10 square meters (108 square feet) in size must be prepared before delivery, along with plumbing and electrical utility hookups. Daiwa claims each Agri-Unit can grow about ten thousand servings of fruits and vegetables each year at an operations cost of about US$4,500, which corresponds to only 45 US cents per head of lettuce.
An Agri-Cube is designed to require little maintenance or attention to the hydroponic and lighting systems. It is delivered ready to use, with all the hydroponic equipment, air conditioning to maintain ideal growing temperatures, a heat-exchanging ventilation system, and special growth lights to encourage faster plant growth installed and functioning. The basic structure is a steel frame building, with anti-rust treatment and floor, wall, and ceiling insulation. Solar panels and air curtains (to better maintain the controlled environment) are available as options.

Community member tending the Agri-Cube's crops

Initially, Agri-Cubes will be marketed to the food service industry. Daiwa intends to extend that focused niche market to include apartment houses and other housing complexes, neighborhood co-ops of perhaps ten households, small-scale stores, and local organic food suppliers.
A video from DigInfo TV appears below that will give a clear overview of the makeup of an Agri-Cube.
Beginning at a price of $70,000, the Agri-Cube may soon be dispensing fresh fruit and vegetables in your neighborhood.
Source: Daiwa House (Google translation), DigInfo TV

Advance could turn wastewater treatment into viable electricity producer

Research at Oregon State University by engineer Hong Liu has discovered improved ways to produce electricity from sewage using microbial fuel cells

In the latest green energy – or perhaps that should be brown energy – news, a team of engineers from Oregon State University (OSU) has developed new technology they claim significantly improves the performance of microbial fuel cells (MFCs) that can be used to produce electricity directly from wastewater. With the promise of producing 10 to 50 times the electricity, per volume, than comparable approaches, the researchers say the technology could see waste treatment plants not only powering themselves, but also feeding excess electricity back to the grid.
The electricity-generating potential of microbes has been known for decades, however, it is only in recent years that efforts to increase the amount of electricity generated to commercially viable levels has started to bear fruit. In MFCs, bacteria are used to oxidize organic matter – be it in wastewater, grass straw, animal waste, and byproducts from such operations as the wine, beer or dairy industries – which produces electrons that run from the anode to the cathode within the fuel cell to create an electrical current.
By adopting a number of new concepts, including reducing the anode-cathode spacing, and using evolved microbes and new separator materials, the researchers say they have been able to produce MFCs that produce more than two kilowatts per cubic meter of liquid reactor volume. The researchers point out this power density is much higher than has been achieved previously and could see the new technology replacing the widely used “activated sludge” process that has been used for almost a century.
While the power density of the new technology is impressive, its potential would be hampered somewhat if it was lacking in the water treatment department. Thankfully, the researchers claim it treats wastewater more effectively than the alternative approach used to generate electricity from wastewater, which is based on anaerobic digestion and produces methane and hydrogen sulfide.
The team has proven the system “at a substantial scale in the laboratory” and is now seeking funding to scale things up with a pilot study. A contained system that produces a steady supply of certain types of wastewater that would provide significant amounts of electricity, such as a food processing plant, is seen as an ideal candidate for such a test.
A pilot study would also assist the team in efforts to reduce the high initial costs of the system by identifying potential reductions in material costs, further optimizing the use of the microbes, and improving the system’s function at commercial scales. If the high initial costs can be brought down through such advances, the OSU team estimates the construction costs of their new technology will be comparable that that of activated sludge systems, even without taking into account future sales of electricity generated at the facility.
“If this technology works on a commercial scale the way we believe it will, the treatment of wastewater could be a huge energy producer, not a huge energy cost,” said Hong Liu, an associate professor in the OSU Department of Biological and Ecological Engineering. “This could have an impact around the world, save a great deal of money, provide better water treatment and promote energy sustainability.”
While turning wastewater treatment from an electricity consumer to an electricity generator has obvious benefits for developed countries, the potential for the technology holds even greater promise in developing countries where both electricity access and sewage treatment is lacking.
The OSU team's findings appear in Energy and Environmental Science.
Source: Oregon State University

Flexible lithium-ion battery technology is on the march

 

A newly developed bendable thin-film lithium-ion battery could help bridge the gap to high-performance bendable electronics 

Researchers at the Korea Advanced Institute of Science and Technology (KAIST) have developed a promising solid state, thin-film lithium-ion battery that claims the highest energy density ever achieved for a flexible battery. The new design, which showed for the first time that high-performance thin films can be used for flexible batteries, may be commercialized as early as next year.
Lithium-ion batteries are a strong candidate for powering the flexible electronics of the future. A high-performance lithium-ion flexible battery would be a giant step toward fully-fledged flexible electronics systems and would open the door to flexible e-paper, wearable devices, and better piezoelectric systems that harvest energy from mechanical forces.
Research is progressing, but seems to have hit an invisible – though very real – performance wall. This is because most designs employ either low-performance flexible organic materials, or polymer binders that take up too much space and decrease the battery's power density. In addition, the cathodes have to be treated at high temperatures to improve performance, but this can't be done effectively on substrates made of flexible polymers.
The new approach developed at KAIST uses high energy density inorganic thin films that can be treated at high temperatures, resulting in the highest-performance flexible lithium-ion batteries yet. "There is no performance difference in energy density, capacity, and cycle life between our flexible battery and bulk batteries," Prof. Keon Jae Lee, who led the research efforts, told Gizmag. "On the contrary, performance is improved by about 10 percent because of the stress release effect."
The batteries are built by sequentially depositing several layers – a current collector, a cathode, an electrolyte, an anode, and a protective layer – on a brittle substrate made of mica. Then, the mica is manually delaminated using adhesive tape, and the battery is enclosed between two polymer sheets to improve mechanical resistance.
Bending the battery affects performance, but not to disastrous levels. With the battery constantly bent at a radius of sixteen millimeters (about the same curvature of a fifty-cent coin) the discharge capacity drops by about seven percent after 100 charge-discharge cycles, compared to a three percent drop when the battery is not bent. Voltage was shown to remain almost constant, dropping by a very modest 0.02 V after the battery was bent and released 20,000 times.
"The technology for commercializing this battery could come in a relatively short time, about a year," says Prof. Lee. But first, the researchers need to find a better, automated way to delaminate the mica substrate – the manual method, involving adhesive tape, is very unpractical and can take up to ten minutes per battery.
"We are investigating a laser lift-off [delamination] process to facilitate mass production of large area flexible lithium-ion batteriesr" says Lee. "Its feasibility is already proven and will be reported in a later paper."
The team is also interested in stacking the structures on top of each other to improve charge density.
A paper describing the battery was recently published on the journal Nano Letters. The video below illustrates the voltage performance of the batteries under mechanical stress.
Source: KAIST

Iron-air batteries may prove a cheap, eco-friendly solution for energy storage

Dr. Narayan is testing one of his new batteries by using it to power a small fan

   

Revamping a concept that was first explored forty years ago, researchers at the University of Southern California (USC) are putting the final touches on a patent-pending design for cheap, rechargeable, high energy density iron-air batteries. Because of their unique features, the batteries look particularly well-suited to the kind of large-scale energy storage that could accelerate the adoption of renewable energy sources.
The quest for a cheap, environmentally friendly rechargeable battery stretches back for decades. For one, lithium-ion batteries were first proposed in the seventies, and only recent advances in materials technology have made this technology into one of the most common, high-performing solutions for today's portable electronics.
Now, a team of USC researchers may have found the key to resuscitating yet another design first proposed around the same time – the iron-air battery.
In the context of battery design, iron has more than a few perks: it is durable, it packs good amounts of energy per unit of mass, it is easily recycled and, last but not least, it is very cheap – in commercial quantities, it only costs around US$1/kg (2.2 lb).
Iron-air batteries were a prime candidate for electric vehicles and military applications after the "oil crisis" that started in 1973. However, research stopped abruptly only years later, when scientists realized that iron-air batteries presented a serious and seemingly insurmountable limitation: whenever the battery was being charged, a wasteful process of hydrolysis drained away about half of the battery's energy.
Back to the present, where researchers at USC have finally found a solution to this wasteful problem. They learned that adding a small amount of bismuth sulfide into the battery shut down the harmful reaction and reduced the waste of energy more than tenfold, from fifty down to just four percent. (Other possible choice materials such as lead or mercury were discarded because, even though they could have worked just as well, they wouldn't have been as safe.)
Another crucial strength of the system is the remarkably simple, cost-effective design of its iron electrode. The researchers combined iron powder with a polyethylene binder, heating the mix to obtain a "pressed-plate" electrode that is simple to make and has high specific energy. With this technology, a battery storing a kWh of energy – the equivalent of 24 new iPad batteries – would require only about $3 worth (3 kg/6.6 lb) of iron powder.
This cheaper iron electrode is driving costs down significantly, and the researchers are targeting an aggressive $100 per kWh for their batteries. For reference, research firm Lux Research puts the cost of lithium-ion batteries at roughly around $600/kWh and says their cost will decrease quite slowly, dropping below the $400/kWh mark no earlier than in 2020.
The iron-air battery is exhibiting very promising durability, with a target life of 5,000 charge-discharge cycles. Even more importantly, the batteries seem to retain good performance when they are being drained quickly: at a two-hour rate of discharge, the batteries are showing a twenty-fold increase in capacity compared to commercially available electrodes.
All in all, this battery design seems well-suited to meet the demands of fast-paced, large-scale energy storage applications, and could supply the ideal "energy grid buffer" for renewable but intermittent energy sources like solar and wind power.
A paper describing the battery was published on a recent issue of the Journal of the Electrochemical Society.
Sources: USC, Lux Research

Flamestick – the firestarter and cooking fuel made from recycled plastic

When used in a stove, a few Flamesticks put out quite a flame

Looking not unlike a plastic Popsicle stick, the Flamestick from Germany's AceCamp is a firestarter made from recycled thermoplastic that measures 3.5 inches (8.9 cm) long by 1/4 inch (6.4 mm) wide. While plastic may sound like a strange way to start a fire, the Flamestick offers several advantages over more traditional materials.

The Flamestick's recycled thermoplastic lights quickly and burns hot, providing a capable firestarter for lighting campfires, stoves, etc. According to AceCamp, a single Flamestick burns at up to 626° F (330° C), and a pair of sticks can reach temperatures over 800° F (426° C). With that much heat, and a claimed five minutes of burn time, Flamesticks can double as cooking fuel. AceCamp's managing director Darko Leo told us he's fried an egg in two minutes and 15 seconds using a solid-fuel backpacking stove powered by Flamesticks.
Flamesticks offer several benefits over other firestarters. Their plastic build means that they aren't susceptible to soaking like other tinder is. So you don't need to worry so much about sealing them up in a dry, waterproof container and can count on them even if they've been rained on or dragged through a river. The fact that Flamesticks can double as cooking fuel means that backpackers can use them for both cooking and firestarting purposes, saving space and weight. AceCamp is also quick to tout the eco-friendly aspects of using recycled materials; however, it's easy to find other recycled or re-purposed firestarters – dryer lint, for instance.

AceCamp recently introduced the Flamestick to its home market of Germany, where Leo told us the product has gone through testing and has proven safe and non-toxic. The company is also in the process of launching in the U.S. and says it has a U.S. patent pending.
I received a pair of sample Flamesticks and put one to the test. The stick lit quickly and began sizzling within seconds. Thanks to its long, thin design, I was able to comfortably hold it on the opposite end while lighting it and use it like a slow-burning match. Acecamp's claim of "no smell" is exaggerated – while it might not be as pungent as burning a non-treated piece of plastic or rubber, it definitely had a smell. The Flamestick burned for about seven minutes. When it went out, it left a small bit of melted residue. The residue did relight, but I ended up having to hold it over a steady lighter flame with a pair of tongs and relight it several times to get it to burn off completely.
While pricing isn't finalized, Leo estimated that a box of 20 Flamesticks will retail for around US$7.
Source: AceCamp GmbH

"Transfer engineering" eliminates toxins from edible part of rapeseed plant

The rapeseed plant is one of the most widely cultivated crops in the world and researchers have now found a way to stop toxins entering edible parts of the plant

As well as being the third largest source of vegetable oil in the world – after soybean and oil palm – rapeseed (also known as rape, oilseed rape, rapa, rappi and rapeseed) is cultivated in Europe primarily for animal feed. But due to high levels of glucosinolates that are harmful to most animals (including humans) when consumed in large amounts, its use must be limited. Now researchers at the University of Copenhagen have found a way to stop unwanted toxins entering the edible parts of the plant, thereby increasing the potential of the plant to be used as a commercial animal feed.
Unlike the healthy glucosinolates found in broccoli, the glucosinolate found in rapeseed has toxic effects in both humans and animals in high doses. It also results in feed meal that is very bitter and unappealing to animals. This has led to the development of breeds with reduced glucosinolate content, such as Canola, which produces edible oil suitable for consumption by humans. However, animal intake of the protein-rich rapeseed cake, which is produced using the byproduct of rapeseeds pressed for oil and used for pig and chicken feed, must be limited, meaning that Northern Europe still imports large amounts of soy cake for animal feed.
By uncovering two proteins responsible for transporting glucosinolates into the seeds of the thale cress plant, a close relative to the rapeseed plant, researchers from the University of Copenhagen were able to produce thale cress without these two proteins and found that their seeds were completely glucossinolate free and therefore suitable for animal feed.
Professor Barbara Ann Halkier, head of the Center of Excellence for Dynamic Molecular Interactions (DynaMo) at the University of Copenhagen’s Faculty of Science says the team calls their new technology for eliminating unwanted substances from the edible parts of plants and crops “transport engineering.”
The team’s research has attracted the attention of Bayer CropScience, one of the world’s biggest plant biotech companies, which is now negotiating with the University of Copenhagen’s Tech Transfer Unit to team up with the research group and apply their approach to producing rapeseed plants with glucosinolate-free seeds.
The team’s research is published in the journal Nature.
Source: University of Copenhagen

New lignin-solvent process harvests biofuel, paper and chemicals from plant material

Researchers have developed a new lignin-solvent process to separate cellulosic biomass into usable components (from left: lignin, hemicellulose, and cellulose)

In order to improve the sustainability credentials of biofuels, experts have been trying to figure out ways to produce them from non-food sources, such as cellulose – the material that makes up the cell walls of plants. Now, researchers from the Wisconsin Institute for Sustainable Technology (WIST) at the University of Wisconsin-Stevens Point have patented a process that they say paves the way for the creation of biofuels from cellulosic plant material.

WIST’s first patent is for a process that makes biofuels and other products from such material, including agricultural left-overs such as corn stover, or plants grown specifically for fuel production, such as hardwood and softwood trees. The method they’ve patented involves an aqueous solvent that separates cellulosic material into pure cellulose and lignin, the substance that gives woody biomass its rigidity. The lignin-solvent mixture can then be separated from the water and becomes a high-energy-density fuel that can be used independently or in combination with biodiesel.

But it’s not just cellulosic ethanol that can come out of this process. Pure cellulose can be used to make paper or can be converted into fermentable sugars. Besides biofuels, the sugars can also be used to make other renewable chemicals for industry including isoprene. It's a material used to make rubber, plastics and pharmaceuticals, but which comes mostly from petroleum.

The patent is an improvement on traditional processes for separating lignin from cellulose employed by the paper industry, which make it more difficult to convert the cellulose to sugars. Also, the lignin that's produced contains chemicals that cannot be easily or economically separated. The new lignin-solvent process results in a purified lignin and pure cellulose, which can be readily used to produce other renewable chemicals. This saves the lignin from being burned, which is the process conventional paper plants typically adopt to recover inorganic chemicals from the pulping process and to produce energy as well.

WIST is working with UW’s WiSys Technology Foundation to license the intellectual property to private industry for development. The researchers envisage several applications for the lignin, including carbon fiber.

Besides the lignin-solvent process, WIST hopes to develop a biorefinery that could be fitted to existing paper mills or to revive idle ones. They have performed the process in the lab and now are looking to develop it into a demonstration-scale plant.

Source: WIST

Breakthrough allows inexpensive solar cells to be fabricated from any semiconductor

A new technique allows photovoltaic solar cells to be produced using any semiconductor

Despite their ability to generate clean, green electricity, solar panels aren't as commonplace as the could be. The main sticking point, of course, is price. Due to their need for relatively expensive semiconductor materials, conventional solar cells don't yet have a price-efficiency combination that can compete with other sources of electricity. Now Profs. Alex Zettl and Feng Wang of Lawrence Berkeley National Laboratory and the University of California at Berkeley have developed seriously unconventional solar cell technology that allows virtually any semiconductor material to be used to create photovoltaic cells.

A solar cell works according to these steps. First, sunlight hits the solar cell and is absorbed by the semiconductor of which the solar cell is made. In the absorption process, electrons are freed from their atoms, allowing them to flow through the semiconductor. The presence of a p-n junction acts as a diode, only allowing the electrons to move in a single direction. (Electrons and holes move in opposite directions, but the electrical current only moves in one.) Metal electrodes then transfer the light-generated electron flow into an electric circuit for use. A p-n junction is the interface between a region of the semiconductor where the dominant charge carriers are holes and a region where the carriers are electrons.

How a solar cell works (Image: Brian Dodson)

A conventional solar cell is made of a thin wafer of a semiconductor with a metallic electrode deposited on its rear side. The side facing the light source is polished more finely than any optical lens, cleaned to the atomic level, and then dopant atoms are deposited onto the front side, whereupon the entire wafer is placed in a high-temperature diffusion furnace.

The purpose of a dopant is to change the dominant charge carrier in the semiconductor from hole-rich to electron-rich, or v.v. In this process the p-n junction that converts incident light into a flow of electrons is formed. Following diffusion, the wafer is again cleaned, and a metallic electrode is grown on the front surface, using arcane rituals to ensure an ohmic contact with the active semiconductor material. (An ohmic contact is an electrical contact that obeys Ohm's law, having no rectifying or diode-like properties.)

The efficiency of conventional solar cells is also limited by the semiconducting materials which are suitable for the manufacture of solar cells by some approximation of the above process. It must be possible for the dominant charge carrier of the semiconductor to be changed between p (hole) and n (electron)-dominated conduction by introduction of chemical dopants, so that a well-behaved p-n junction is formed. It must also be possible to make a satisfactory electrical contact between the electrodes and the semiconductor.

There are many semiconductor materials with optical properties and electronic band-gaps well suited to conversion of light to electricity for which one or another of the rather rigid criteria for manufacture of conventional solar cells fails. These include many metal oxides, sulfides and phosphides, which are plentiful and inexpensive, but have been considered unsuitable because it is so difficult to alter their electronic structure chemically (e.g., through doping). For example, zinc oxide is a semiconductor well suited for capturing violet and near ultraviolet light, which is wasted by most conventional solar cells.

We now have Zettl and Wang's unconventional solar cells. Broken down, the expensive parts of making regular solar cells are the semiconductor wafer, forming a high-quality p-n junction under the surface of the wafer, and making ohmic electrical contact with the front and back of the wafer. Aside from providing a semiconductor wafer (usually of a cheaper material), the new solar cells require none of this.

The new technology is called "screening-engineered field-effect photovoltaics" (SFPV). An electrode is deposited on the front of the semiconductor wafer, which partially screens the semiconductor from an electric field generated between the front and rear electrodes. Assume the semiconductor is naturally p-type, so that it has an excess of holes. The applied electric field then penetrates the semiconductor surface slightly, attracting electrons toward the surface and repelling holes. As a result, the semiconductor near the surface changes from p-type to n-type (electron-rich), and a buried p-n junction has been generated – not by chemistry, but by use of carefully tailored electric fields. An extra bonus is that the front electrode automatically forms an ohmic contact with the semiconductor wafer.

“Our technology requires only electrode and gate deposition, without the need for high-temperature chemical doping, ion implantation, or other expensive or damaging processes,” said lead author of a paper describing the new technology, William Regan. “The key to our success is the minimal screening of the gate field which is achieved through geometric structuring of the top electrode. This makes it possible for electrical contact to and carrier modulation of the semiconductor to be performed simultaneously.”

Two approaches to engineering the screening properties of SFPV electrodes - fingered electrodes on the left, graphene electrodes on the right

Two electrode configurations that exhibit the SFPV concept have been developed. In one, the electrode in contact with the semiconductor wafer is formed of a row of narrow fingers, while in the other the partial screening is accomplished by placing a layer of graphene atop the semiconductor wafer. In both cases, high-quality p-n junctions are formed in semiconductors for which this structure was previously impossible.

Low cost, high efficiency solar cells? Sounds like a winner here – let's see when and if it hits the market.

The team's research is published in the journal Nano Letters.

Source: Lawrence Berkeley National Laboratory

Panansonic develops world's most efficient artificial photosynthesis system

A newly developed 'artificial photosynthesis' system from Panasonic could be used to turn carbon dioxide into harmless organic compounds 

Panasonic has recently developed an artificial photosynthesis system that, using a simple and straightforward process, can convert carbon dioxide into clean organic materials with what it says record efficiency. This development may lead to the creation of a compact way of capturing pollution from incinerators and electric power plants and converting them into harmless – even useful – compounds.

Over the last few years, we've covered a number of artificial photosynthesis systems that could use sunlight to split water into hydrogen and oxygen.Some of them could do it cheaply and reliably, operating ten times more efficiently than real leaves.

The "artificial photosynthesis" developed here, however, takes things to a new level: it not only splits water into its atomic components, but also uses the resulting hydrogen to convert carbon dioxide (CO₂) into formic acid (HCO₂H) – the same stuff that makes ant bites sting, and is used in the chemical industry to make dyes and fragrances.

The technology sees light shine on a nitride semiconductor inside a water container, where the nitride acts as a photo-electrode and splits water into oxygen and hydrogen. Then, boosted by a metal catalyst, the electrons are excited with enough energy for CO₂ reduction to take place and create formic acid.

The solution is remarkably simple, much more so than previous attempts. Past systems relied on complicated multi-stage processes and often employed complex organic compounds. But, the researchers found, such compounds can limit overall performance. With their all-inorganic artificial photosynthesis system, the researchers achieved a record efficiency of 0.2 percent, which they claim is a significant improvement over previous results.

Crucially, because this system is scalable, can rely on both direct sunlight and focused light, and the amount of reaction products is exactly proportional to the light power, the researchers say it could be used to capture and convert wasted carbon dioxide from incinerators and electrical generation plants.

Source: Panasonic Corporation

Chimera Energy develops fracking technique that uses no water

Dry fracturing promises to open up shale fields without ground water contamination

“Fracking” may sound like something out of Battlestar Galactica, but it’s actually short for “hydraulic fracturing.” It is one of the most remarkable success stories in the history of the energy industry and its ability to open up previously unprofitable oil and gas resources in North America, Europe and China holds the promise of centuries of cheap, clean and abundant energy free of Middle Eastern control. However, it has raised the concerns of some environmentalists. Chimera Energy Corporation of Houston, Texas, has announced that they are licensing a new method for extracting oil and gas from shale fields that doesn't contaminate ground water resources because it uses exothermic reactions instead of water to fracture shale.

Hydraulic fracturing works by pumping hundreds of thousands of gallons of water down shafts to deep-lying shale beds. The water is pumped at pressures of up to 15,000 psi (1,000 ATM), which cracks the shale, forming fissures that allow any gas or oil trapped in it to flow freely. It’s opened up fields previously thought worthless that now promise to yield trillions of barrels of oil and far more natural gas. However, it has raised concerns about how environmentally safe it is.

Despite the fact that fracking is used mainly in deep, sealed geological deposits, there is the fear that it may pose a danger to groundwater. Depending on the method involved and the type of oil field, various other materials are added to the water used in Fracking, such as sand, foaming agents, gels and friction reducers. The concern is that the water, which is pumped out after the process, may either leak these substances plus radioactive radon from the well directly into aquifer layers, or contaminate water supplies after pumping out.

For this reason, some fracking engineers prefer non-hydraulic methods. One of these, used recently in New York State, swaps the water for gelled propane. The idea being that the propane reverts to a gas at the end of the process and can be pumped out, leaving any additives behind in the well, much like boiling seawater and leaving behind the salt.

The Chimera process takes this a step further by eliminating any working liquid. Details of the process have not been made public yet due to patent concerns, but Chimera Energy uses what is called “dry fracturing” or “exothermic extraction.” First developed in China, this involves using hot gases rather than liquid to fracture the shale. This was originally intended for wells in arctic regions where water used in fracking freezes, but Chimera Energy has developed it for general use.

In dry fracturing, metal oxides, ultra-expansive evaporants and pumice are pumped into the well. The metal oxides react with one another to form an exothermic reaction. Extremely hot gases are generated that expand and crack the shale. Meanwhile, the pumice shoots in and reinforces the fractures, keeping them from closing and allowing the gas or oil to flow.

Chimera Energy claims that not only is the technique environmentally safe, but that it is compatible with any existing well in the world.

Source: Chimera Energy Corporation