Fractionation of lignocellulosic biomass components by prehydrolysis-organosolv delignification

Conference · Fri Dec 31 04:00:00 EST 1993

OSTI ID:140240

Papatheofanous, M G; Koullas, D P; Koukios, E G ^[1]; Billa, E; Monties, B ^[2]

---

1. National Technical Univ. of Athens (Greece)
2. Centre de Biotechnologie, Grignon (France)

Based on economic, environmental and other considerations the feasibility of converting lignocellulosics to chemicals and other industrial products could be significantly enhanced if all major components, that is cellulosic fibers, hemicellulosic polymers and lignin could be efficiently utilized. Such a two stage process scheme under investigation by this group consists of a mild hydrolytic treatment fractionating hemicelluloses as high purity sugar solutions, followed by acid- or alkali-catalyzed low temperature organosolv delignification aiming at the production of a high quality cellulosic pulp and high reactivity lignin-derived oligomers. Results reports here concern the effects of selective hemicellulose fractionation (between 0% and 90%) and variable delignification conditions (catalytic system, ethanol: water ratio) on the pulping stage, using wheat straw as raw material. Pulp yield, degree of delignification, mechanical properties of handsheets and lignin structure are compared to those of conventional pulping. Optimal pulp properties are obtained following saccharification of about 50% of hemicelluloses whereas a somewhat lower degree of fractionation is required to avoid significant condensation reactions in lignin. Although organosolvents rich in ethanol are more selective towards delignification and cellulose degradation is then limited, their pulping ability decreases at low water content, i.e. less than 35% v/v. The combination of alkali and ethanol is vital for the production of pulps with low Kappa Numbers (40).

• Research Organization: National Renewable Energy Lab., Golden, CO (United States)
• OSTI ID: 140240
• Report Number(s): NREL/CP--200-5768-Vol.2; CONF-9308106--Vol.2; ON: DE94000435
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
BIOMASS
CHEMICAL FEEDSTOCKS
CHEMICAL PREPARATION
DELIGNIFICATION
ETHANOL
FIBERS
FRACTIONATION
HEMICELLULOSE
HYDROXIDES
LIGNIN
MECHANICAL PROPERTIES
ORGANIC SOLVENTS
POLYMERS
PRODUCTION
RENEWABLE RESOURCES
SACCHARIFICATION
STRAW
TEMPERATURE DEPENDENCE
WASTE PRODUCT UTILIZATION
WHEAT