Insight into the deep eutectic solvent pretreatment of oil palm empty fruit bunches: Effects of temperature, empty fruit bunch to solvent ratio, and time

This work aimed to comprehensively examine the pretreatment efficiency of oil palm empty fruit bunches (EFB) using two different types deep eutectic solvent (DES) mixtures, i.e., choline chloride/imidazole (DES-I) and chloride/glycerol (DES-G) in terms pretreated EFB structural composition enzymatic hydrolysis. The influence temperature (55 °C, 90 125 160 195 °C), ratio (1:5, 1:10, 1:15, 1:20), time (2 h, 4 6 h) on performance generated black liquor was examined. optimal conditions for were 1:5 ratio, 2 h DES-I solvent, 1:10 DES-G solvent. carbohydrates bunch with DES-I, EFB1 DES-G, EFB2 increased 66.1%, 64.6%, respectively. hydrolysis resulted higher glucan conversion (92.4%) compared EFB2, indicating that more efficient than pretreatment. X-ray diffraction, Fourier transform infrared spectroscopy, variable-pressure scanning electron microscopy confirmed removal lignin hemicelluloses from during