The integration of green chemistry into future biorefineries

The use of biorefineries for the production of chemicals as well as materials and energy products is key to ensuring a sustainable future for the chemical and allied industries. Through the integration of green chemistry into biorefineries, and the use of low environmental impact technologies, we can establish future supply chains for genuinely green and sustainable chemical products. The first step in these future biorefineries should be the benign extraction of surface chemicals; here the use of greener solvents, such as supercritical carbon dioxide and bioethanol, should be considered. The residues will often be rich in lignocellulosics and the effective separation of the cellulose is a major challenge which may, in the future, be assisted by greener solvents, such as ionic liquids. Lignin is nature's major source of aromatics; we need new ways to produce small aromatic building blocks from lignin in order to satisfy the enormous and diverse industrial demand for aromatics. Fermentation can be used to convert biomass into a wide range of bioplatform chemicals in addition to ethanol. Their green chemical conversion to higher value chemicals is as important as their efficient production; here clean technologies such as catalysis - notably biocatalysis and heterogeneous catalysis - the use of benign solvents, and energy efficient reactors are essential. Thermochemical processes for the conversion of biomass, such as the production of pyrolysis oil, will also play an important role in future biorefineries and here again green chemistry methods should be used to go to higher value downstream chemicals. (C) 2008 Society of Chemical Industry and John Wiley & Sons, Ltd