Tunable solvents for fine chemicals from the biorefinery

We must develop efficient, economical, and environmentally-benign biorefineries as part of our energy future, and in the Southeastern US, the logical feedstock is forest products. A necessary facet of making such biorefineries commercially viable would be to integrate the production of high value-added chemicals from components of the feed stream, as done in the petroleum industry. The opportunities are exceptional, in that the feel stream is not merely alkanes, but rather highly functionalized and even chiral materials. This necessitates new methods. We demonstrate tunable solvents such as nearcritical water and gas-expanded liquids for useful reactions and separations. We are using CO2 expanded methanol to recover vanillin, syringol, and syringaldehyde from a paper mill black-liquor sidestream. Also we describe an integrated system for a prepulping extraction of the wood chips with an alcohol-CO2 mixture, followed by depolymerization and dehydration in nearcritical water, to yield levulinic acid, glucaric acid and their derivatives.