Influence of pretreatments on sustainability of bioethanol production from napier grass

Abstract

The influences of pretreatments and acid hydrolysis conditions in bioethanol production from Napier grass were investigated. The alkaline and acid pretreatments removed 6.63 % and 5.71 % of lignin more than the untreated grass. The recommended acid concentration in hydrolysis was 35% sulphuric acid for duration of 20 to 40 min. Fermentation of samples from acid and alkaline pretreatments for 48 h produced the highest ethanol concentration of 13 %v/v. However, when the sustainability was considered, these chemical pretreatments used chemical and required sample' neutralization prior to fermentation thus an additional chemical cost occurred and released more chemical to environments in comparison to steam pretreatments which produced slightly lower ethanol of 11 %v/v.