Augmentation of cellulose extraction from oil palm empty fruit bunch via rapid and energy-saving deep eutectic solvent-pulsed electric field pretreatment

This study devises a novel method for enhancing cellulose extraction from oil palm empty fruit bunches (OPEFB) via utilizing binary and ternary DES deep eutectic solvents (DES) incorporated pulsed electric field (PEF) pretreatment, followed by chlorine-free bleaching. The effectiveness of the pretreatment method was validated with a comprehensive analysis of cellulose obtained and detailed energy requirement estimation. Choline chloride-lactic acid DES mixture aided with the electroporation effect exerted by the PEF process yielded 37% cellulose and 19% lignin. The properties of the extracted cellulose are comparable to that of the commercial (microcrystalline cellulose) standards. The binary and ternary DES employed in the PEF pretreatment of OPEFB showed higher solid and better DES recovery potential than those employed in the conventional heating (CH) techniques. Remarkably, the method reduced energy consumption by 98% and 60 times faster than the CH methods. Further subjecting the pretreated DES-PEF pretreatment successive by chlorine-free bleaching process, cellulose extract was further enhanced, indicating the sustainable process scheme is feasible for cellulose extraction from OPEFB, thus providing a promising approach for eco-friendly and efficient biomass utilization into value-added products.