Authors : Mohd Asyraf Kassim, Nasrin Abu Bakar, Loh Soh Kheang and Astimar Aziz
Abstract: Malaysia is one of the largest palm oil producers in the world and the industry has contributed the significant income to the country for many years. With the rapid growth of palm oil production in Malaysia, the amount of biomass residues generated also has shown a corresponding increase. Mass generation of palm biomass particularly Empty Fruit Bunches (EFB) has been identified as one of the main environmental issue generated from palm oil industry. Conversion of EFB into value added products such as bioethanol has been identified as an alternative way to reduce accumulation of EFB in the plantation. In this study, the effects of different EFB concentration, inoculums size and nitrogen sources on bioethanol production using pre-treated EFB were investigated. The pulverized EFB was initially pre-treated with 1% (w/v) sodium hydroxide (NaOH) followed by acid hydrolysis using 0.7% (v/v) sulfuric acid (H2SO4) and enzymatic saccharification prior to fermentation via Separate Hydrolysis and Fermentation (SHF) mode with Saccharomyces cerevisiae were carried out. The enzymatic hydrolysis process of EFB indicated that the highest glucose concentration was obtained by using 15% (w/v) EFB with 26.35 g L-1 glucose and 4.6 g L-1 xylose, respectively. The fermentation of hydrolysate obtained from saccharified EFB at different solid loading indicated that the highest ethanol production was achieved at 10% (w/v) EFB with 10.45 g L-1 ethanol corresponding to ethanol yield (Yp/s) of 0.53 g g-1 glucose. The most suitable inoculums size for ethanol production from saccharified EFB hydrolysate was 10% (v/v) active S. cerevisiae and additional of peptone in the EFB hydrolysate was not significantly affected (p<0.5) the ethanol production. However, additional of peptone in the saccharified EFB hydrolysate was able to reduce period of fermentation from 72-48 h of incubation.
Mohd Asyraf Kassim, Nasrin Abu Bakar, Loh Soh Kheang and Astimar Aziz, 2011. Influence of Solid Loading Concentrations, Inoculums Size and Nitrogen Sources on Ethanol Production from Empty Fruit Bunches (EFB) Hydrolysate in Separate Hydrolysis and Fermentation (SHF). Research Journal of Applied Sciences, 6: 310-319.