Hydrolysis of lignocellulosics at low enzyme levels: Application of the AFEX process

• Published in: Bioresource technology Vol. 56; no. 1; pp. 111 - 116
• Main Authors: Dale, B.E., Leong, C.K., Pham, T.K., Esquivel, V.M., Rios, I., Latimer, V.M.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford Elsevier Ltd 01.04.1996; Elsevier Science
• Subjects: AFEX process; Agronomy. Soil science and plant productions; ammonia fiber explosion process; beta-glucosidase; Biological and medical sciences; cellulases; corn fiber; crop residues; dietary fiber; ethanol fuel; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; hydrolysis; Lignocellulose; Panicum virgatum; pretreatment; reducing sugars; ryegrass straw; Use of agricultural and forest wastes. Biomass use, bioconversion; yields; Lignocellulose; cellulases; ethanol fuel; hydrolysis; crop residues; AFEX process; Thermochemical treatment; Monocotyledones; Waste utilization; Lolium; Plant fiber; Biofuel; Biomass; Energy crop; Straw; Alcoholic fermentation; Gramineae; Angiospermae; Bioenergy; Carbohydrate; Agricultural waste; Pretreatment; Zea mays; Ethanol; Enzyme; Saccharification; Lignocellulosics; Panicum virgatum; Vegetal waste; Hydrolysis; Ammonia; Reducing sugar; Renewable energy; Cellulolytic enzyme; Herbaceous plant; Spermatophyta
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/0960-8524(95)00183-2

The presumed high cost of cellulase enzymes is seen as a major economic hurdle in ethanol fuel production from lignocellulosic biomass. One way to reduce enzyme cost is to use much less enzyme per unit of biomass hydrolysed. The ammonia fiber explosion (AFEX) process produces a highly reactive biomass but the relationship between AFEX treatment conditions, enzyme loadings and hydrolysis yields has never been thoroughly explored. We report here the effects of AFEX treatment on the initial rates and 24 h hydrolysis yields for several crop residues and lignocellulosic materials using low enzyme levels (1–5 IU/g dry biomass). Near theoretical sugar yields are obtained for some AFEX treatment conditions at 1 IU/g for corn fiber and 5 IU/g for switchgrass. Implications of the experimental results are discussed.