Optimization of microwave assisted dilute ammonia pretreatment of oil palm empty fruit bunch using response surface methodology

Abstract

Indonesia is the largest producer of palm oil in the world. Around one-fifth of the palm oil processing, weight end up as solid waste, named as oil palm empty fruit bunch (OPEFB). OPEFB is lignocellulosic biomass which contains cellulose, hemicellulose, lignin and minerals. The utilization of cellulose and hemicellulose requires pretreatment to open the lignin bond. This study examines the pretreatment of OPEFB using microwave assisted dilute ammonia. The OPEFB (30 - 40 mesh) was pretreated by ammonia solution with solid-liquid ratio of 1:10 under variated parameters such as ammonia concentration (7.5; 10; 12.5 %), microwave power (280; 560; 840 Watt) and reaction time (3; 6; 9 minutes).The hemicellulose content of all samples was characterized according to SNI 01-1561-1989. The results were optimized using response surface methodology with Box-Behnken model. The model showed that the highest hemicellulose content of 27.3% can be reached at pretreatment conditions of 665-Watt microwave power at 7.5 % ammonia concentration for 3 minutes.

Effect of Microwave Pretreatment on Some Properties of Bamboo (Gigantochloa apus) for Bioethanol Production

“…Pretreatment of lignocellulosic biomass is necessary to facilitate hydrolysis of its cellulose and hemicellulose fractions, by removing the lignin content, before other processes in common biochemical production [11]. In bioethanol production from lignocellulosic biomass, pretreatment is needed to enhance the accessibility of cellulase enzyme to cellulose and minimize the number of enzyme inhibitors formed during the pretreatment process [12]. Microwave (MW) pretreatment technology is recently used to convert lignocellulosic biomass to sugars and ethanol due to its fast treatment time, selective processing, instantaneous control, and acceleration of the reaction rate [13].…”