Study on technology optimization of lignin removalin cellulose extraction from wheat bran by combination of ultrasound and hydrogen peroxide

Abstract

Background: Currently, cellulose is more closely related to people's daily life and widely used in various fields, textile industry, food, medicine and health care etc. Thus the increasing research focuses on cellulose extraction. Wheat bran, by-product of flour processing, is rich in cellulose, its cellulose extraction is conducive to the rational use of wheat bran. In wheat bran, cellulose is wrapped by lignin, semi-cellulose and pectin, which prevented it from high yield, therefore the removal of lignin, semi-cellulose and pectin benefits to the extraction efficiency. Materials and Methods: Taking wheat bran as raw material and using the method of ultrasonic assisted, the researchers studied the factors, affecting lignin removal, to find out the optimum conditions. Effects of hydrogen peroxide concentration, liquid-solid ratio, temperature, ultrasonic pretreatment power, reaction time on removal rate of lignin were analyzed respectively. On the basis of the above experiments of single factors, design orthogonal experiment to determine the optimum conditions of lignin removal. Results: Experimental results showed that removal rate of lignin reached 73.87% with the ratio of liquid to solid of 15:1, the ultrasonic treatment time of 10 h at 50EC, the power of 100 W and the hydrogen peroxide concentration of 3%. Conclusion: Traditionally, lignin removal was carried out by chemical reagent from straw of various kinds and wood chips, along with the environmental pollution. In this study, taking wheat bran as material by the combination of ultrasound and chemical reagent process, lignin was removed to a great degree, hence cellulose was extracted with high yield and chemical reagent experienced decreased consumption, which provided enough material for food industry, medicine industry and other areas.