Dec 14 2008
Instead of fossil fuels going in your gas tank, how about adding a pinch of salt? That may be the case in the future as a new process is under development to convert a type of salt into a biofuel.
New properties of imidazolium salts (IMSs) could convert carbohydrates into versatile chemical compounds for biofuel production, according to a study by researchers at Singapore's Institute of Bioengineering and Nanotechnology (IBN).
IBN researchers used IMS to develop a new catalyst system for converting sugars into 5-hydroxymethylfurfural (HMF), a major compound used in biofuel chemistry and the petroleum industry.
IBN researchers were able use IMSs to synthesize uniform gold nanoparticles within seconds at room temperature. The ultrafine (1-2 nm) nanoparticles remained stable for up to six months at 4°C.
Unlike conventional synthesis techniques using borane or borohydride reduction processes, IBN's method does not require a strong reducing reagent yet is able to produce gold nanoparticles under very mild reaction condition with remarkable efficiency.
IBN's new synthesis protocol could easily scale up for industrial applications.
Commonly used as solvents for various organic reactions, IMSs are room-temperature ionic liquids chemically stable and have low vapor pressure.
The race continues to compensate for the lowering fossil fuel reserves and to combat global warming effects. That is why researchers across the globe continue to search for sustainable, renewable alternative energy sources.
Biofuels are currently the only sustainable source of liquid fuels available, but the lack of highly efficient methods to convert carbohydrates into chemical compounds for biofuel production is one reason for the slow down in any replacement of petroleum feedstock by biomass.
HMF and its 2,5-disubstituted furan derivatives can replace key petroleum-based building blocks, and several known catalysts can work in the dehydration of sugars to form HMF.
However, most of them also produce undesirable side reactions and rehydrate HMF to form acid.
With IMSs as the starting point, IBN researchers developed N-heterocyclic carbenes (NHC)-metal complexes as catalysts to transform sugars into HMF. These offer flexibility as researchers can modify the catalytic activity by changing specific properties of the NHC. The researchers were able to extract HMF easily as the sole product. IBN's new catalyst achieved the highest reported yields of HMF so far, for both fructose and glucose feedstocks.
"Our HMF yields were as high as 96% for fructose and 81% for glucose," said IBN Principal Research Scientist Dr. Yugen Zhang. "As both the catalyst and the ionic liquid can be recycled, our technology is more environmentally friendly and would potentially lead to cost savings in the biofuel manufacturing process."
"Our discovery paves the way for more effective treatment of various degenerative diseases, as well as the conversion of biofuels, helping to alleviate some of the pressing concerns facing our global community," said IBN Executive Director Professor Jackie Y. Ying.