Energy from domestic refuse by enzymatic degradation of cellulosic fibre waste into sugars and ethanol: initial laboratory studies

Abstract

The search for commercially viable biogenic sources of transport fuel, such as ethanol, is nowa priority among developed countries. Sugar- and starch-containing crops currently supportmature industries producing ethanol by yeast fermentation. The potential of bulk plantmaterials (biomass crops, agricultural wastes and domestic refuse) is enormous, but suchligno-cellulosic compounds are difficult to degrade into simple sugar molecules. In the USAand Canada, commercial development programmes are under way to develop new enzymaticand fermentation technologies and to reduce process costs.We investigated the potential of processed waste material derived from domestic refuse as asource of simple sugars for conversion to ethanol. "Pure" cellulose was almost completelydegraded to reducing sugars by cellulase C0I3L, a mixed enzyme preparation, and byTrichoderma viride cellulase, whereas enzymes from other fungal species performed lesswell. T viride achieved less than I 0% (by weight) conversion of waste material to reducingsugars in 2 hour incubations, whereas C013L cellulase gave sugar yields of up to 35%.Extended incubation times gave little increase in yield. These results support the feedstockpotential of this material. Alternative techniques, such as pre-treatment with ferulic acidesterase to improve the effectiveness of degradation, are discussed.