Hydrolysis of crystalline cellulose to glucose in an autoclave containing both gaseous and liquid water

Abstract

Hydrolysis of cellulose was investigated in an autoclave. The yield of glucose produced from crystalline cellulose was dependent on the amount of water added to the autoclave. The highest glucose yield of 17% was obtained after 5 h reaction at 190 °C in the presence of a small amount of liquid water in the autoclave. When hydrolysis was carried out in saturated vapor pressure in the autoclave in which cellulose was separated from liquid water, nearly the same yield of 15% was obtained. However, when cellulose was soaked in water, the yield was decreased to about 5%. The results suggested that water vapor plays an important role in hydrolysis of the β-1,4-glycosidic bonds of cellulose. In addition, hydrolysis of the β-1,4-glycosidic bonds and degradation of produced glucose under hydrothermal conditions were investigated by using cellobiose (a dimer of glucose) and authentic glucose, respectively.