Separation and Purification of Hemicellulose by Ultrafiltration

Abstract

[EN]During hydrolysis treatments, where the main objective is the solubilization of hemicelluloses, several undesirable reactions may occur. As a result, monomeric sugars and nonsaccharide compounds are obtained in the liquor. In the present study, autohydrolysis liquor resulting from the corn waste hydrolysis treatment (180 ºC, 30 min) was filtered successively increasing the membrane cutoff (1, 5, and 10 kDa) to observe the potential of this technology for hemicellulose purification and fractionation by molecular weight. The experimental results showed that the 10 kDa retentate liquor fraction has the highest hemicellulose concentration (6.10 g/L) and it was constituted by defined molecular weight components (Mw = 2880), with low content in smaller compounds and inorganic material. Hemicelluloses have been isolated from each fraction and were analyzed by different analytical techniques (FT-IR, TGA, 1H NMR, and CHNS O elemental analysis) to determine that it was possible to improve the physicochemical characteristics of the original liquor by ultrafiltration technology.