Improving the biodegradability of rice straw by electrochemical pretreatment

The efficacy of NaOH, alkaline hydrogen peroxide (NaOH-H 2 O 2 ), electrochemically produced NaOH-H 2 O 2 (eNaOH-H 2 O 2 ) and electrohydrolysis (EH) pretreatments was investigated for anaerobic digestion of rice straw. The cumulative biogas production was enhanced by 8%, 22% and 14% in the NaOH-H 2 O 2 , eNaOH-H 2 O 2 and EH relative to conventional NaOH pretreatment. The chemical and electrochemical pretreatments decreased the crystallinity of cellulose and created a porous surface vein. Electrochemical NaOH-H 2 O 2 pretreatment is efficient to promote microbial degradation of lignocellulose for biogas production while the risks associated with the transportation and storage of H 2 O 2 are avoided. EH reduces the pretreatment time significantly and is a promising approach for utilizing rice straw biomass to produce renewable energy.