Electron beam irradiation and dilute alkali pretreatment for improving saccharification of rice straw

Abstract

Rice straw is one of the most abundant and low-cost biomasses available in the world. Thus, the rice straw as a potential candidate for future energy and chemical resource has been intensively studied in order to use as the current fossil fuels. However, the structure of rice straw makes it difficult to hydrolyze into fermentable sugars owing to the cellulose in rice straw being tightly surrounded by hemicellulose and lignin, thus pretreatment of rice straw is needed for this process. In the present study, an alkali pretreatment method assisted by electron beam irradiation was investigated to improve the saccharification in an enzymatic hydrolysis yield. After pretreatment, cellulose in rice straw was increased from 39.5 to 71.1%, and lignin decreased from 19.5 to 6.4%. The sugar yield of the pretreated rice straw increased with an increase in irradiation dose. The results of XRD and Fourier transform infrared spectroscopy analyses showed that the properties of the straw were changed by this pretreatment, which favored the following enzymatic hydrolysis.