Pretreatments of cellulose pyrolysate for ethanol production by Saccharomyces cerevisiae, Pichia sp. YZ-1 and Zymomonas mobilis

Cellulosic pyrolysate containing levoglucosan was chemically hydrolyzed and a maximum glucose yield of 17.35% was obtained by the hydrolysis with 0.2 mol/l H2SO4 at 121°C for 20 min. The total initial glucose was maintained at 41.9 g/l by diluting the hydrolysate. Ten detoxification methods were employed including either single addition of solid Ca(OH)2 (to pH 6.0 or 10.4) or its combinations with absorbents. The neutralization+diatomite shaking method gave the hydrolysate which was most completely fermented by Saccharomyces cerevisiae and Pichia sp. YZ-1. The maximal ethanol yield of 0.45 g/g glucose was obtained by S. cerevisiae.