BIOCONVERSION OF WASTE PAPER TO ETHANOL

A preferred process is described for efficient bioconversion of waste paper to ethanol. The paper was given a short saccharification by cellulase enzymes at 45-degrees-C followed by fermentation in the continued presence of the enzymes at 37-degrees-C. Ethanol yields were 350-400 litres/t of waste paper, at 8% ethanol by volume. In some of these runs, commercial cellulase was used, in others our laboratory preparation of cellulase was used; in both cases a small amount of cellabiase was also needed. There was no pretreatment before saccharification as is common with lignocellulosics. A new fermenter design well suited for waste paper processing or for cellulose production is described. The amount of paper in municipal solid waste in North America is about 100 million t yearly, enough, upon bioconversion, to replace 16% of all North American gasoline by ethanol.