Combination of Sulfuric Acid with Cellulose during the Hydrolysis with a Small Amount of Concentrated Sulfuric Acid

The combination of sulfuric acid with cellulose occurring during the hydrolysis of cellulose in a small amount of concentrated sulfuric acid has been investigated. The amounts of the soluble and the insoluble glucose polymers produced from cellulose, and the amount of sulfuric acid combined with them, have been estimated. To obtain an effective concentration of sulfuric acid on the cellulose, the concentration of the sulfuric acid must be greater than about 60%. The sulfuric acid concentration in the cellulose-sulfuric acid-water system can not exceed 75%, even when the initial concentration exceeds 85%. The amount of soluble glucose polymer (g.) produced by the action of 100 g. of sulfuric acid is given by 0.0384 exp(0.0958C+4.06r)/[1+0.00132 exp(0.0815C+4.06r)] (C is “initial” concentration of sulfuric acid (%) and r, sulfuric acid-cellulose ratio).