Kinetic modeling of hemicellulose hydrolysis in the presence of homogeneous and heterogeneous catalysts

A1 Journal article (refereed)

Internal Authors/Editors

Publication Details

List of Authors: Tapio Salmi, Dmitry Yu. Murzin, Päivi Mäki-Arvela, Bright Kusema, Bjarne Holmbom, Stefan Willför, Johan Wärnå
Publication year: 2014
Journal: AIChE Journal
Volume number: 60
Issue number: 3
Start page: 1066
End page: 1077
eISSN: 1547-5905


Kinetic models were developed for the hydrolysis of O-acetyl-galactoglucomannan (GGM), a hemicellulose appearing in coniferous trees. Homogeneous and heterogeneous acid catalysts hydrolyze GGM at about 90°C to the monomeric sugars galactose, glucose, and mannose. In the presence of homogeneous catalysts, such as HCl, H2SO4, oxalic acid, and trifluoroacetic acid, the hydrolysis process shows a regular kinetic behavior, while a prominent autocatalytic effect was observed in the presence of heterogeneous cation-exchange catalysts, Amberlyst 15 and Smopex 101. The kinetic models proposed were based on the reactivities of the nonhydrolyzed sugar units and the increase of the rate constant (for heterogeneous catalysts) as the reaction progresses and the degree of polymerization decreases. General kinetic models were derived and special cases of them were considered in detail, by deriving analytical solutions for product distributions. The kinetic parameters, describing the autocatalytic effect were determined by nonlinear regression analysis. The kinetic model described very well the overall kinetics, as well as the product distribution in the hydrolysis of water soluble GGM by homogeneous and heterogeneous catalysts. The modelling principles developed in the work can be in principle applied to hydrolysis of similar hemicelluloses as well as starch and cellulose.

Last updated on 2019-16-07 at 04:48