Production of Lingin-based Reformulated Gasoline Components

Abstract

The National Renewable Energy Laboratory in conjunction with the Shabtai Group at University of Utah and Sandia National Laboratories, is developing a process for the conversion of lignin biomass to higher valued chemicals such as reformulated gasoline components. The process consists of a dilute NaOH-based extraction of lignin from a solid residue received from a separate simulataneous saccharification and fermentation (SSF) process. The lignin solution is then diluted to a specified concentration and directly injected into a high-pressure, continuous flow reactor that carries out a base-catalyzed de-polymerization reaction. Successful lignin extraction of the SSF residue has been narrowed to three primary variables; solvent concentration, solvent to residue weight ratio, and extraction temperature. Initial extraction studies that vary solvent concentration and solvent to residue weight ratios at room temperature have narrowed range of NaOH concentrations to O.IM - 0.3M and the solvent-residue weight ratios to 3.0 - 7.5. The temperature variable has yet to be studied, but is expected to complete the extraction optimization process. Fundamental work on the base-catalyzed de-polymerization reaction has been done by the Shabtai group and replicated at Sandia National Laboratories. The continuous-flow reactor design is currently in the developmental stage, however, initial experiments have shown that de-polymerization does occur and has been confirmed by characterization of reactor products using GPC and GC-MS.