Simultaneous Delignification and Furfural Production of Palm Oil Empty Fruit Bunch by Novel Ternary Deep Eutectic Solvent

The most considerable solid waste from crude palm oil plants is oil palm empty fruit bunch (OPEFB) which contains cellulose, lignin, and hemicellulose. Hemicellulose can be hydrolyzed to xylose and then converted to furfural via dehydration. Pretreatment is one of the steps in the bioconversion of lignocellulose material to reduce lignin. This study developed a one-pot process to conduct pretreatment and furfural production simultaneously. This process uses a green solvent called ternary deep eutectic solvent (DES). DES was synthesized by mixing choline chloride, oxalic acid, and ethylene glycol with a molar ratio of 1:1:2 (CHOAEG). Simultaneous delignification and furfural production were carried out in a stainless steel reactor. The temperature was varied at 100, 120, and 150 °C, with the various processing time at 30, 60, and 90 min, respectively. The highest furfural concentration reached 9.68 g/L, and the delignification was achieved up to 55.81% at 150 °C for 90 min. The OPEFB pretreated was hydrolyzed by cellulase and achieved 90.79% glucose yield. Overall, the simultaneous delignification and furfural production process by ternary DES CHOAEG demonstrated a novel and efficient process by reducing the number of complex processes stages of biorefinery lignocellulose.