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.