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.