Furfural production from vine shoots through optimized microwave-assisted pretreatment

Furfural is a versatile bio-based platform for producing renewable fuels and chemical products. In this work, furfural production was assessed using vine shoots as a renewable raw material that currently lacks viable applications. Acid-pretreatment by microwave irradiation was optimized for vine shoots, to maximize xylose recovery and minimize energy consumption. Optimal conditions were determined at 160 ℃, 0.8% (w/v) H 2 SO 4 , 5 min, which resulted in 79.78% xylose recovery. The prehydrolysate obtained under these conditions was used as a substrate for furfural production by chloride salt-catalyzed dehydration using LiCl, MgCl 2 , and FeCl 3 solutions. The effect of the catalyst, its concentration, and the reaction time on the dehydration of xylose to furfural was studied. The highest furfural yield of 80.04% with a selectivity of 93.89% was achieved when the treatment was carried out using 0.3 M LiCl for 5 min. However, FeCl 3 exhibited the highest catalytic activity, achieving a furfural yield of 73.20% and 90.99% selectivity at 0.1 M concentration in a shorter time. Xylose-to-furfural conversion without added salt achieved a maximum furfural yield of 75.47% (85.98% selectivity), although the process required a longer time. As the main novelty, this work optimized microwave-acid pretreatment integrated with the xylose-to-furfural conversion from vine shoots, a promising strategy for the efficient production of furfural, a key platform chemical.