Recovery of glucose from an aqueous ionic liquid by adsorption onto a zeolite-based solid

Batch adsorption was studied for d-glucose on different types of zeolite-based adsorbents from an aqueous solution of 1-ethyl-3-methylimidazolium acetate ([C2mim][CH3COO]). The goal of the studies is to establish a possible process for recovery of glucose and of ionic liquid for recycle in a continuous process for converting a wild grass (miscanthus) to a liquid biofuel. A significant increase in glucose uptake is obtained when ionic liquid is present in the aqueous glucose solution. Highest glucose uptake was obtained for Faujasite structures and for zeolites with a high Si/Al ratio. Adsorption on KX-zeolites can reach 45% glucose removal in one step. Desorption of glucose into water is complete in 50 min at 50 °C and in 10 min at 60 °C.

► We use zeolite-based sorbents for the recovery of glucose and IL in biofuel processing. ► We study the batch adsorption for glucose from an aqueous solution of [C2mim][CH3COO]. ► 45% of glucose removal was achieved using KX-zeolites. ► The presence of IL increases glucose uptake with no evidence of IL adsorption. ► Desorption of glucose is complete in 50 min at 50 °C.