Patent ID: 8603251

Claim:
A method for preparing a main hydrolysate by hydrolyzing plant cellulose materials with concentrated sulfuric acid, the method comprising: (1) dissolving a portion of the plant cellulose materials in a sulfuric acid solution to form a first hydrolysate; (2) adding an amount of concentrated sulfuric acid having a concentration of more than 80 wt % into the first hydrolysate when the sulfuric acid in the first hydrolysate can no longer dissolve the plant cellulose materials, and adding another portion of the plant cellulose materials to form a second hydrolysate; and (3) repeating step (2) when the sulfuric acid in the second hydrolysate can no longer dissolve the plant cellulose materials until all the plant cellulose materials are completely hydrolyzed, thereby obtaining the main hydrolysate.