IONIC LIQUID PRETREATMENT OF NAPIER GRASS FOR THE PRODUCTION OF BUTANOL

摘要

Lignocellulosic biomass mainly consists of cellulose, hemicellulose, and lignin in a complicatedrnstructure, which has rigid linkage of cellulose with lignin. Therefore, pretreatment is required to break down ligninrnseal in order to increase enzyme accessibility in enzymatic hydrolysis. Napier grass from Saraburi province, Thailandrncan be used to produce reducing sugars. This study focuses on the effects of metal salt concentration (FeCl_3),rnpretreatment time, and temperature during acidic-aqueous ionic liquid pretreatment ([EMIM][OAc]/CH_3COOH)rnunder microwave irradiation on the reducing sugar yield. The optimum condition of these variables is determined andrncompared with the pretreatment without the addition of FeCl_3. Furthermore, the effect of anti-solvent is alsorninvestigated. The results show that the maximum total reducing sugar concentration of 10.07 g/L was obtained underrnthe optimum condition of 160 ℃, 100 min, and 60 mM FeCl_3. At the different optimum pretreatment conditions, thernaddition of FeCl_3 in [EMIM][OAc]/CH_3COOH pretreatment could improve the total sugar yield. At the samernpretreatment conditions and anti-solvent volume, the addition of FeCl_3 had a negative effect onrn[EMIM][OAc]/CH_3COOH pretreatment. Moreover, acetone-water mixture was the most effective anti-solvent.