Mild peroxyformic acid fractionation of Miscanthus x giganteus bark. Behaviour and structural characterization of lignin
2012 (English)In: Industrial crops and products (Print), ISSN 0926-6690, Vol. 35, no 1, 261-268 p.Article in journal (Refereed) Published
Miscanthus x giganteus bark was subjected to mild fractionation with peroxyformic acid by a two stage process. A factorial experimental design was used to study and quantify the effect of the variables (formic acid concentration (80-90%), hydrogen peroxide concentration (0.2-0.4%), temperature of the first stage (60-80 degrees C), and treatment time of the second stage (60-120 min)) on the main parameters of fractionation: pulp yield, remaining lignin and total polysaccharides in pulp. The dependence of lignin precipitation rate on hydrogen peroxide concentration in liquor was also studied. Hydrogen peroxide concentrations inferior to 0.5% seems to be suitable to recover high percentages of lignin. The isolated lignin was analysed by 2D-HSQC, (13)C- and (31)P NMR spectroscopy, FTIR spectroscopy, size-exclusion chromatography and chemical analysis. The most important chemical modifications taken place in the lignin during the fractionation were identified: beta-O-4' cleavage and hydrolysis of LC-bond structures. The C9-formula was also determined: C(9)H(6.81)O(2.90)(OCH(3))(0.68)(COOH)(0.07)(OH(Ph))(0.38)(OH(Al))(0.33) .
Place, publisher, year, edition, pages
2012. Vol. 35, no 1, 261-268 p.
Miscanthus x giganteus, Peroxyformic acid, Fractionation, Lignin recovery, Lignin characterization
IdentifiersURN: urn:nbn:se:kth:diva-47962DOI: 10.1016/j.indcrop.2011.07.013ISI: 000296110700039ScopusID: 2-s2.0-80051917309OAI: oai:DiVA.org:kth-47962DiVA: diva2:457567
QC 201111172011-11-182011-11-152011-11-18Bibliographically approved