Abstract: Under microwaves irradiation, the enhancement of sulfuric acid hydrolysis process of rice straw was studied. The effects of microwave power, irradiation time, mass fraction of sulfuric acid and rice straw amount in 1L sulfuric acid solution on yield of reducing sugar were investigated. Compared with conventional acid hydrolysis, microwave radiation can significantly raise the rate of hydrolysis and shorten the time of saccharification. By means of orthogonal experiment, the conditions for sulfuric acid hydrolysis of rice straw under microwaves irradiation were optimized as follows: microwave power 280 W, irradiation time 30 min, sulfuric acid mass fraction 25%, rice straw amount in 1 L sulfuric acid solution 30 g, and the reducing sugar yield reached 26.45%.

Key words: microwave, rice straw hydrolysis, reducing sugar, orthogonal experiment