Food vs. fuel
Non-food crops for biofuel

It has long been recognized that the huge supply of agricultural cellulose, the lignocellulosic material commonly referred to as "Nature's polymer", would be an ideal source of material for biofuels and many other products. Composed of lignin and monomer sugars such as glucose, fructose, arabinose, galactose, and xylose, these constituents are very valuable in their own right. To this point in history, there are some methods commonly used to coax "recalcitrant" cellulose to separate or hydrolyse into its lignin and sugar parts, treatment with; steam explosion, supercritical water, enzymes, acids and alkalines. All these methods involve heat or chemicals, are expensive, have lower conversion rates and produce waste materials. In recent years the rise of "mechanochemistry" has resulted in the use of ball mills and other mill designs to reduce cellulose to a fine powder in the presence of a catalyst, a common bentonite or kaolinite clay, that will hydrolyse the cellulose quickly and with low energy input into pure sugar and lignin. Still currently only in pilot stage, this promising technology offers the possibility that any agricultural economy might be able to get rid of its requirement to refine oil for transportation fuels. This would be a major improvement in carbon neutral energy sources and allow the continued use of internal combustion engines on a large scale.
keywords:letter_frequency