Effects of combination of steam explosion and microwave irradiation (SE–MI) pretreatment on enzymatic hydrolysis, sugar yields and structural properties of corn stover

Abstract

A novel process named combination of steam explosion and microwave irradiation (SE–MI) method was investigated and compared with steam explosion (SE) method for pretreating corn stover under 540W microwave power and 3min microwave irradiation time. Both of the two pretreatment methods were operated at 170–210°C for 3–15min. Results showed that compared to SE process, SE–MI process enhanced the enzymatic hydrolysis yields of both glucose and xylose, and slightly increased the total sugar yield. The maximum glucose yield, xylose yield and total sugar yield of the process were 57.4%, 17.8% and 75.2% (corresponding to 100% maximum total sugar in feedstock), respectively, obtained at 200°C for 5min. SE–MI pretreatment showed attractive advantage in inhibiting the increase of biomass crystallinity. The crystallinity following SE–MI pretreatment was 19% lower than that following SE pretreatment at 190°C for 5min.