Ethanol and Methane Production from Oil Palm Frond by Two stage SSF

A two step, included process producing ethanol from oil palm fronts (OPF) by two-stage simultaneous saccharification and Saccharomyces cerevisiae fermentation followed by anaerobic digestion of its effluent to produce methane was investigated. OPF was soaked in dilute sulfuric acid, hydrogen peroxide and water consequently pretreated by microwave for preparing of cellulose and followed by simultaneous saccharification and fermentation. The result indicated OPF soaking in water gave a maximal ethanol yield was 0.32 g-ethanol/g-glucose which was 62.75% of the ethanol theoretical yield (0.51g-ethanol/g-glucose). The effluent from the ethanol production process was used to produce methane with the yield of 514 ml CH4/g VS added. Therefore, soaking in water and microwave co-pretreatment could helpful due to its low toxicity and low corrosion compare to sulfuric acid and hydrogen peroxide which improves the efficiency of enzymatic hydrolysis. The maximum energy output of the process (745 kWh/ton of OPF) was about 72% of the energy contributed by cellulose fraction, contained in the oil palm frond. (C) 2014 Published by Elsevier Ltd.