Biological production of liquid fuels from biomass. Annual report, September 1, 1978-August 31, 1979

The production of liquid fuels from renewable resources such as poplar wood and lignocellulosic wastes from a refuse hydropulper were studied. The particular scheme being studied involves the conversion of a cellulosic residue, resulting from a solvent delignified lignocellulosic feed, into either high concentration sugar syrups or into ethyl and/or butyl alcohol. The process is aimed at achieving total raw material utilization and maximization of high value by-product recovery. Specific goals of the investigation are the demonstration of the process technical feasibility and economic practicality and its optimization for maximum economic yield and efficiency. The construction of a pilot apparatus for solvent delignifying 150g samples of lignocellulosic feeds has been completed. Also, an analysis method for characterizing the delignified product has been selected and tested. Delignified samples are now being prepared and tested for their extent of delignification and susceptibility to enzyme hydrolysis

Biological production of organic solvents from cellulosic wastes. Progress report, September 15, 1976--September 14, 1977

The objectives of this project are to optimize a modular process to convert cellulosic wastes to butanol and other oil-sparing chemicals. Research to date has focused on developing analytical methods, establishing a good data base and improving cellulase yields. Reliable assay methods for the Thermoactinomyces cellulase complex have been developed, measuring glucose and reducing sugar from filter paper and Avicel for total cellulase activity, viscosity change with carboxymethyl cellulose for the endoglucanase activity, and fluorescence change with methylumbelliferyl-..beta..-D-glucopyranoside for ..beta..-glucosidase activity. Isoelectric focusing within the range pH 3.5 to 6.0 has proved to be a quick and useful means of determining effective cellulase complex composition. About 10 different proteins are present in the fermentation broth. Detailed procedures for uv and near uv plus 8-methoxy-psoralen mutagenesis have been developed, and four mutants having 50% greater activity than the parent YX strain have been isolated. Cellulase production by Thermoactinomyces is growth related and is maximum when growth stops at 12 to 16 hours with 1 to 5% Avicel at pH 7.0 to 7.2 and 55/sup 0/C. A multistage fermenter has been assembled for optimization of butanol versus acetone production by Cl. acetobutylicum. A preliminary economic assessment, currently indicating butanol at just above 30 cents/lb, is being continuously updated