Optimization of hemicellulose recovery from black liquor using ZnO/PES ultrafiltration membranes in crossflow mode

Black liquor, one of the by-products of pulp and paper industry, is an underexplored resource with great potential for the recovery of valuable biopolymers such as lignin and hemicelluloses. In this work, the hemicellulose was recovered from this liquor, containing 17 % of total dissolved solids, using ZnO/ polyethersulfone ultrafiltration membrane. The hemicellulose was concentrated into the retentate stream while lignin was permeated through these membranes. The effects of transmembrane pressure (1 to 4 bar), time (up to 8 h) and crossflow velocity (0.1 and 0.2 m/s) were studied for ultrafiltration pro-cess operating in crossflow mode. The highest rejection of hemicellulose was achieved up to 90.7 +/- 1.9 % at 4 bar. At 3 bar, the yield of hemicellulose was ??? 90 % and 84 % for the volume reduction up to 60 % and 78 %, respectively. Mathematical modeling was applied to analyze the membrane fouling mechanism responsible for the flux reduction during filtration at constant pressure, as well as to predict the changes in hemicellulose and lignin concentration during the filtration process. CO 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Automated summary

Black liquor, a by-product of the pulp and paper industry, contains valuable biopolymers like lignin and hemicelluloses. This study successfully recovered hemicelluloses from black liquor using ZnO/ polyethersulfone ultrafiltration membrane, providing a new pathway for resource recovery.