Researchers at George Washington University have bolted together an ungainly contraption that they say efficiently uses the energy in sunlight to power a novel chemical process to make lime, the key ingredient in cement, without emitting carbon dioxide. The device puts to work about half of the energy in sunlight (solar panels, in comparison, convert just 15 percent of the energy in sunlight into electricity).Cement production alone emits 5 to 6 percent of total man-made greenhouse gases, and most of that comes from producing lime. Some of the greenhouse-gas emissions from conventional cement production come from using fossil fuels to heat up limestone to high temperatures—about 1,500 ⁰C. Replacing fossil fuels with renewable energy is straightforward, but not necessarily economical. The new work focuses on a harder problem. About 60 percent of the carbon-dioxide emissions from cement production is inherent to the process. Lime is made by heating up limestone—that is, calcium carbonate—until it releases carbon dioxide.The new process changes the chemistry. Rather than emitting carbon dioxide, it converts the gas, using a combination of heat and electrolysis to produce oxygen and either carbon or carbon monoxide, depending on the temperatures employed. Both carbon and carbon monoxide are useful products that might otherwise have been made using fossil fuels.To make the electrolysis practical, the researchers mixed solid calcium carbonate with liquid lithium carbonate, which is molten at the temperatures that are optimal for the process—about 900 ⁰C. The liquid form is conducive to electrolysis. The elevated temperatures lower the amount of electricity needed to electrolyze, and cause the lime to precipitate out of the mixture, making it easy to collect. (At lower temperatures, the lime is more soluble, so it doesn’t precipitate.)

New Cement-Making Method Could Slash Carbon Emissions – Technology Review

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This is how the idea is introduced:

Donald Sadoway is working on a battery miracle — an inexpensive, incredibly efficient, three-layered battery using “liquid metal.”

Professor Sadoway explains that his angle has been to design around the oil price point, not around some wild and cool technology that can never compete economically. He goes on to say he wants his battery to use abundantly available materials and work in a simple, low cost way. The talk is loaded with an understated arrogance and false modesty.

After the talk I did some reading on one of the electrode materials, Antinomy (Sb). I discovered that it is very rare, produced almost exclusively in China, and expected to be completely depleted on Earth in a few years. Could this be the same plentiful material that Sadoway is talking about? His presentation suggests that for his system to work at the grid level, he’s going to need a whole lot of Sb, and possibly continue needing a new supply forever.

Either he knows something we don’t or he is just getting warmed up using antimony and will be substituting for it with some other more commonly available materials.

I’d like to hear more about this antimony and what I am missing…..

Donald Sadoway: The missing link to renewable energy | Video on TED.com

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Scientists at the Center for Nanotechnology and Molecular Materials at Wake Forest University have developed a thermoelectric fabric that converts body heat into electricity. The material is made of layers of interlocking carbon nanotubes and plastic fibers, and feels similar to felt. The thermoelectric technology develops electric current from temperature differences, such as the difference between anatomical temperature and room temperature.According to Wake Forest researcher Corey Hewitt, “We waste a lot of energy in the form of heat. For example, recapturing a car’s energy waste could help improve fuel mileage and power the radio, air conditioning or navigation system. Generally thermoelectrics are an underdeveloped technology for harvesting energy, yet there is so much opportunity.”The first prototypes of Power Felt yielded 140 nanowatts of power from 72 layers of nanofabric, and the researchers are currently attempting to increase the output of the technology.“I imagine being able to make a jacket with a completely thermoelectric inside liner that gathers warmth from body heat, while the exterior remains cold from the outside temperature,” says Hewitt. “If the Power Felt is efficient enough, you could potentially power an iPod, which would be great for distance runners. It’s definitely within reach.”

Transmaterial » Blog Archive » Power Felt

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Turns out that researchers at the Department of Energy’s BioEnergy Science Center, located Caldicellulosiruptor obsidiansis, a naturally occurring bacterium, onsite at Yellowstone, Sure enough, it thrives at extremely high temperatures, breaks down organic material such as sticks and leaves in its natural environment, and scientists hope to transfer this capability to biofuel production tanks.

A team out of Lee Lynd’s lab at Dartmouth has been at work on Thermoanaerobacterium saccharolyticum, a thermophilic anaerobic bacterium that ferments xylan and biomass-derived sugars, to produce ethanol at high yield.

University of Texas researchers Alan Lambowitz and Georg Mohr have been working on Thermosynechococcus elongatus, a cyanobacterium discovered in Japan that can survive at temperatures of up to 150 degrees Fahrenheit.

A team of researchers from the DOE, Novozymes and Concordia University have been unlocking the genome of Thielavia terrestris and Myceliophthora thermophila, fungi that thrive in high-temperature environments above 45°C and whose enzymes remain active at temperatures ranging from 104°F to 160°F (40 °C to 75 °C),

We also recently looked at at work by biologists at Berkeley and the University of Maryland, who discovered a microbe in a Nevada hot spring that has an enzyme that processes cellulose and remains active at a record 109 degrees Celsius (228 degrees Fahrenheit), significantly above the 100℃ (212℉) boiling point of water.

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Chemical reducing agents (sodium dithionite) or bioglycerol (as H and e−-donor under irradiation in the presence of ZnS-A as photocatalyst) are able to back-convert NADP+ into NADPH, which is used as e−-donor in the enzymatic reduction of CO2 into CH3OH. In doing so, the molar ratio CH3OH/CO2 has been increased (without recycling of NADP+) using the photocatalyst.

DOI: http://dx.doi.org/10.1002/cssc.201100484

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Lower olefins are key building blocks for the manufacture of plastics, cosmetics, and drugs. Traditionally, olefins with two to four carbons are produced by steam cracking of crude oil–derived naphtha, but there is a pressing need for alternative feedstocks and processes in view of supply limitations and of environmental issues. Although the Fischer-Tropsch synthesis has long offered a means to convert coal, biomass, and natural gas into hydrocarbon derivatives through the intermediacy of synthesis gas (a mixture of molecular hydrogen and carbon monoxide), selectivity toward lower olefins tends to be low. We report on the conversion of synthesis gas to C2 through C4 olefins with selectivity up to 60 weight percent, using catalysts that constitute iron nanoparticles (promoted by sulfur plus sodium) homogeneously dispersed on weakly interactive α-alumina or carbon nanofiber supports.

DOI: http://dx.doi.org/10.1126/science.1215614

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