Bioconversion of plant biomass to ethanol. Third quarterly and bimonthly report, July 1--September 30, 1977
The studies of biological delignification have focused on the adaptation of the lignocellulosic thermophilic mold Chrysosporium pruinosum to growth on maple wood fibers. The addition of trace elements and thiamine hydrochloride to the C. pruinosum growth medium has been found to stimulate culture growth by a factor of about two. The nutritional salt tolerances of C. pruinosum have been determined. Nutrient concentrations below of about 2.5 times that required to support C. pruinosum growth have no significant deleterious inhibitory effects. Work on the design and construction of a bench-top high solids biological delignification bioreactor has been initiated. The mixed culture microbiological studies have focused mainly on nutritional growth requirements and rates of cellulose digestion and ethanol production. In small test tube mixed culture (sporocytophaga (US) + thermophilic bacillus (NW)) fermentations, the rate of cellulose degradation was found to proceed at a very high volumetric efficiency, 2.4 g/l-hr. The yield of ethanol from the mixed culture fermentation of cellulose varied between 24 and 50% of theoretical. The higher yields were obtained in the presence of insoluble calcium carbonate added to retard the rate of pH decline and to increase the CO/sub 2/ tension. Bench-top fermentations at the 1 liter scale have been performed to verify, under controlled pH, agitation, and dissolved oxygen conditions, the results achieved in small scale test tube experiments. The specific growth rate of thermophilic bacillus NW on glucose was calculated to be 0.59 hr/sup -1/. In mixed culture fermentations of amorphous and microcrystalline cellulose the specific rate of substrate depletion was calculated to be 0.087 hr/sup -1/ and 0.0346 hr/sup -1/, respectively. Ethanol production in these fermentor runs was slower than the rates of acetic acid production. In the fermentation of microcrystalline cellulose, 2,3 butanediol was also produced.
- Research Organization:
- General Electric Co., Schenectady, NY (USA). Research and Development Center
- DOE Contract Number:
- EG-77-C-02-4147
- OSTI ID:
- 6701877
- Report Number(s):
- COO-4147-3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Bioconversion of plant biomass to ethanol. First bimonthly and quarterly report
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Related Subjects
CELLULOSE
ENZYMATIC HYDROLYSIS
ETHANOL
BIOSYNTHESIS
WOOD
DELIGNIFICATION
BIOCONVERSION
CALCIUM CARBONATES
FUNGI
PH VALUE
RESEARCH PROGRAMS
THERMOPHILIC CONDITIONS
ALCOHOLS
ALKALINE EARTH METAL COMPOUNDS
BIOMASS
CALCIUM COMPOUNDS
CARBOHYDRATES
CARBON COMPOUNDS
CARBONATES
CHEMICAL REACTIONS
DECOMPOSITION
ENERGY SOURCES
HYDROLYSIS
HYDROXY COMPOUNDS
LYSIS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PLANTS
POLYSACCHARIDES
RENEWABLE ENERGY SOURCES
SACCHARIDES
SOLVOLYSIS
SYNTHESIS
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