Monitoring wood-related biorefinery process streams is important as the composition of raw material and its variations have a great impact on the production outcome as well as on the process control. In this paper, the applicability of a simple type of capillary zone electrophoresis method to profiling heterogeneous woodbased samples was studied by grouping the peaks in the overall electropherograms. A comparison between 210 and 270 nm as an example confirmed the identification of a monosaccharide peak in the carbohydrate electropherogram. The analytical method applied in this study was found suitable, firstly, in profiling the samples based on correlation of multiple detection wavelengths and, secondly, in characterizing the total carbohydrate composition by grouping detected peaks by the compound type. Compounds were detected in their extracted form without timeconsuming pretreatment procedures. Differences in the raw material and process conditions were successfully identified by comparing characteristic peaks in the sample electropherograms of an example case.
Lignin is the mass waste product of pulp and paper industry mostly incinerated for energy recovery. Lignin is, however, a substantial source of raw material for derivatives currently produced in costly wet oxidation processes. The pulsed corona discharge (PCD) for the first time was applied to lignin oxidation aiming a cost-effective environmentally friendly lignin removal and transformation to aldehydes. The experimental research into treatment of coniferous kraft lignin aqueous solutions was undertaken to establish the dependence of lignin oxidation and aldehyde formation on the discharge parameters, initial concentration of lignin and gas phase composition. The rate and the energy efficiency of lignin oxidation increased with increasing oxygen concentration reaching up to 82 g kW-1 h-1 in 89% vol. oxygen. Oxidation energy efficiency in PCD treatment exceeds the one for conventional ozonation by the factor of two under the experimental conditions. Oxidation at low oxygen concentrations showed a tendency of the increasing aldehydes and glyoxylic acid formation yield.