Rice husk-based solid acid for efficient hydrolysis and saccharification of corncob

This work studied preparation of rice husk-based solid acid and its application for efficient hydrolysis and saccharification of corncob. Rice husk-based solid acid (RH-SO3H) was prepared by one-step carbonization and sulfonation method. Analysis demonstrated that RH-SO3H exhibited aromatic carbon sheets structure bearing - SO3H, -COOH and -OH groups. The RH-SO3H was then used to hydrolyse and saccharify corncob. Compared with solid acids made from activated carbon and microcrystalline cellulose, the RH-SO3H showed the highest catalytic efficiency with the maximum reducing sugar yield of 486.53 mg/g and xylose of 253.03 mg/g, which was twice and five times higher than that of control, respectively. Its high efficiency was attributed to -OH and - COOH groups functioned synergistically with -SO3H to hydrolyse lignocellulose by adsorbing beta-1,4-glucan in corncob. This study provides a green and effective utilization technology of lignocellulosic biomass.