Two research projects of the National Research Programme “Resource Wood” have developed new processes to replace petroleum with wood for the production of important chemicals. These precursors are used in the manufacture of pharmaceuticals, plastics or fertilisers.
Petroleum means fuel, but not only: petrochemicals are a core ingredient of the chemical industry. Without oil, there would be no plastics and few pharmaceuticals or fertilisers. Finding a renewable resource as an alternative to oil will be crucial to face the foreseeable decline in oil extraction.
Two research projects of the National Research Programme “Resource Wood” (NRP 66) have made significant advances towards replacing oil with biomass derived from plants, in particular from wood. Their goals are complementary, as each one uses one of the two main constituents of wood: cellulose and lignin. These are the two most common organic components on Earth and, importantly, are renewable.
Sviatlana Siankevich of EPFL has designed new catalytic processes to efficiently transform cellulose into hydroxymethylfurfural (HMF), a very important precursor for the production of plastics, fertilisers or biofuels.(*) Inspired by the action of fungi degrading rotting wood, the team of Philippe Corvini at FHNW in Muttenz (BL) has selected enzymes capable of cutting lignin into aromatic compounds useful for making solvents, pesticides, plastics such as polystyrenes as well as active pharmaceutical ingredients.
Chemicals instead of paper
Cellulose is a long chain of carbohydrate (sugar) molecules and accounts for about two-thirds of wood’s weight. “It is mainly used for paper production, and the residuals could be better valorised by being transformed into useful chemicals,” says Sviatlana Siankevich of EPFL’s Institute of Chemical Sciences and Engineering. With colleagues from Queen’s University in Canada and the National University of Singapore, the EPFL team led by chemist Paul Dyson synthesised several types of ionic liquids (molten salts) to convert cellulose into HMF, an important molecule for the production of commodity chemicals. In a single step, their reaction reached a 62% yield, a new record.
“Our procedure operates at mild conditions, that is, without very high temperatures or pressure or strong acids”, says Siankevich. “We’ve also been able to reduce the amount of undesired by-products, an important point if the reaction is to be scaled up for industrial processes. Our process can work with wood, but it’s often easier to use cellulose extracted from herbaceous plants.”