Anaerobic co-digestion of POME and NaOH- pretreated empty fruit bunch

Empty Fruit Bunch (EFB) as lignocellulosic biomass is the second largest waste after Palm Oil Mills Effluent (POME) in oil palm processing. EFB can act as a source of nutrition with POME in the production of biogas by anaerobic digestion (AD). However, EFB’s lignin content inhibits biogas production by hindering the access of microbes to the nutrients. Hence, the EFB needs to be pretreated to break the lignin content. This study focuses on the effect of NaOH pretreatment of EFB on the biogas production of a 21 days AD. NaOH concentrations of 0.5 M, 1.25 M, and 2 M were used to soak the EFB for 60 minutes at a temperature of 100˚C. A maximum delignification of 26.465% was obtained with 2 M NaOH. Compared to mono-digestion AD, the highest increase in biogas production of 251.16% was obtained also with the 2 M NaOH pretreatment. Hence, 2 M NaOH was found to be the optimum concentration to pretreat EFB as a co-substrate.