A Nine-Zone Simulating Moving Bed for the Recovery of Glucose and Xylose from Biomass Hydrolyzate

Abstract

A nine-zone simulated moving bed (SMB) process was developed to recover two sugars, glucose and xylose, from biomass hydrolyzate with 88% recovery and near 100% purity. The SMB system consists of two coupled binary SMB rings which are operated at the same switching time. The first ring consists of five zones, in which sulfuric acid (a fast-moving solute) is recovered as the raffinate product, acetic acid (a slow-moving solute) is partially recovered as the extract product, and a mixture of the two sugars (intermediate solute) and the rest of the acetic acid is recovered in a bypass stream, which is input as the feed to the second ring. The second ring consists of four zones, in which the sugars are recovered as the raffinate product and acetic acid is recovered as the extract product. Experimental SMB data obtained using either hydrolyzate or synthetic mixtures of glucose, xylose, sulfuric acid, and acetic acid are presented and analyzed with a lumped mass-transfer model. Single-component and multicompone...