| 摘要 |
PROBLEM TO BE SOLVED: To efficiently saccharify a biomass raw material including cellulose.SOLUTION: A coarsely pulverized biomass raw material including cellulose is heated and pulverized in an atmosphere with the water content less than saturation vapor pressure and under pressure close to normal pressure until cellulose is amorphousized and degraded in molecular weight into a soluble substance with molecular weight nearly equal to that of an oligosaccharide (S2), and lignin in an aqueous solution is decomposed by making the aqueous solution formed by dissolving and extracting the soluble substance in water irradiated with ultraviolet light (S4). By decomposing the lignin with ultraviolet irradiation, lignin can be decomposed in a non-contact manner, within a shorter time period, and more efficiently than the case in which lignin is decomposed by using an alkali or an acid, because any control of the solvent such as neutralization is unnecessary. Consequently lowering of the rate of saccharification in the saccharification step caused by an admixture of lignin is suppressed, and cellulose is efficiently saccharified. |
