Successive and quantitative fractionation and extensive structural characterization of lignin from wheat straw
2014 (English)In: Industrial crops and products (Print), ISSN 0926-6690, Vol. 61, 249-257 p.Article in journal (Refereed) Published
A unique process for the fractionation of lignin from wheat straw is proposed: Ball milling for 8 h, followed by a direct and an acidolysis-assisted dioxane-water extraction. Four distinctly different lignin structures were thus obtained: (1) one free non-core lignin, which is a cellulose-lignin with lowest molar mass and highest contents of p-hydroxycinnamic acids, condensed phenolic hydroxyl groups and tricin moieties, and with a detectable amount of cinnamyl alcohols; (2) two core xylan-lignins differing in their degree of branching as indicated by their xylose/arabinose ratios of >4 and similar to 2, respectively; (3) one core cellulose-lignin which is the residual fraction resistant to all extractions. Based on the mass balance of Klason lignin the yields of these four fractions are 13.8%, 18.1%, 37.5% and 12.5%, respectively, thus accounting for 82% of the total KL in wheat straw. Therefore, the isolated lignin fractions could be considered as highly representative allowing a good insight into the different features of wheat straw lignin.
Place, publisher, year, edition, pages
2014. Vol. 61, 249-257 p.
Lignin, Fractionation, Wheat straw, 2D HSQC NMR, Ball-milling
IdentifiersURN: urn:nbn:se:kth:diva-155776DOI: 10.1016/j.indcrop.2014.07.013ISI: 000343339200031ScopusID: 2-s2.0-84904874804OAI: oai:DiVA.org:kth-155776DiVA: diva2:763117
QC 201411132014-11-132014-11-132014-11-13Bibliographically approved