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Independent Professional: Experienced educator and management consultant for engineering educational institutions, researcher, trainer, technical consultant on sustainable technologies, related to cement manufacturing and characterisation, using industrial and agricultural wastes in cement and concrete, durability of concrete and fuel cell power.

Wednesday, September 22, 2010

Carbon dioxide to building materials

MIT biological engineers,  have found a way to convert carbon-dioxide emissions to useful building materials, using genetically altered yeast.

Every year, about 30 billion metric tons of carbon dioxide are pumped into the Earth’s atmosphere from power plants, cars and other industrial sources (such as cement plants) that rely on fossil fuels. Scientists who want to mitigate carbon dioxide’s effects on global climate have started experimenting with storing the gas underground, a process known as carbon sequestration. However, there are still many unknowns surrounding the safety and effectiveness of that strategy.

Genetically engineering ordinary baker’s yeast, Angela Belcher, the W.M. Keck Professor of Energy and two of her graduate students, Roberto Barbero and Elizabeth Wood, have created a process that can convert carbon dioxide into carbonates that could be used as building materials. Their process, which has been tested in the lab, can produce about two pounds of carbonate for every pound of carbon dioxide captured. Next, they hope to scale up the process so it could be used in a power plant or industrial factory.

The team plans to try scaling up the process to handle the huge volumes of carbon dioxide produced at fossil-fuel-burning power plants. If the process is successfully industrialized, a potential source for the mineral ions needed for the reaction could be the briny water produced as a byproduct of desalination.

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Monday, September 20, 2010

Biomass for high-value chemicals

ScienceDaily (2010-09-02) -- Chemist Walter Trahanovsky was trying to produce sugar derivatives from biomass using high-temperature chemistry. He was surprised when his research also produced significant yields of high-value chemicals.

The biomass conversion process is based on the chemistry of supercritical fluids, fluids that are heated under pressure until their liquid and gas phases merge. In this case, Trahanovsky said the key results are significant yields of ethylene glycol, propylene glycol and other chemicals with low molecular weights. He said the process also produces alkyl glucosides and levoglucosan that can be converted into glucose for ethanol production or other uses.

Uses for ethylene glycol include auto antifreeze, polyester fabrics and plastic bottles. Propylene glycol has many uses, including as a food additive, a solvent in pharmaceuticals, a moisturizer in cosmetics and as a coolant in liquid cooling systems.

The starting materials are cheap and the products are reasonably high-value chemicals.

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Wednesday, September 1, 2010

Nanotechnology for water purification

ScienceDaily (2010-09-01) -- Researchers have developed a water-purifying filter that makes the process more than 80,000 times faster than existing filters. The key is coating the filter fabric -- ordinary cotton -- with nanotubes and silver nanowires, then electrifying it. The filter uses very little power, has no moving parts and could be used throughout the developing world.

Instead of physically trapping bacteria as most existing filters do, the new filter lets them flow on through with the water. But by the time the pathogens have passed through, they have also passed on, because the device kills them with an electrical field that runs through the highly conductive "nano-coated" cotton.
Cholera, typhoid and hepatitis are among the waterborne diseases that are a continuing problem in the developing world.

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