0000000000543884
AUTHOR
Aivars Zhurinsh
Obtaining lignocellulosic biomass-based catalysts and their catalytic activity in cellobiose hydrolysis and acetic acid esterification reactions
Global challenges prompt the world to modify its strategies and shift from a fossil-fuel-based economy to a bio-resource-based one with the production of renewable biomass chemicals. Different processes exist that allow the transformation of raw biomass into desirable bio-based products and/or energy. In this work different biochars that were obtained as a by-product from birch chip fast pyrolysis and carbonization were used as is or chemically/physically treated. These sulfonated carbon catalysts were compared to a commercially available sulfonated styrene-divinylbenzene macroreticular resin (Dowex 50W X8). Characterisation (water content and pH value, FTIR, base titration, element analysi…
Catalytic Activity of Char Obtained from Fast Pyrolysis in Esterification Reactions
In this study different pathways for obtaining activated carbon with catalytical activity were analysed. Industrially fast pyrolysis is an efficient way of lignocellulosic biomass processing, since in this process various important high value chemicals are obtained. Biochar is obtained as the by-product in fast pyrolysis process from which activated carbon can be acquired with further chemical activation. Different methods for chemical activation of biochar were tested with the obtained activated charcoals being used as a catalyst in esterification reactions to evaluate their potential use as a heterogenic catalyst. Highest catalytical activity was observed when biochar was pre-treated with…
Comparison of photodiode array, evaporative light scattering, and single-quadrupole mass spectrometric detection methods for the UPLC analysis of pyrolysis liquids
ABSTRACTIt is important to analyze pyrolysis liquids to evaluate the yield of valuable products as well as unfavorable by-products. This work focuses on choosing detectors for reversed-phase ultra high-performance liquid chromatography analysis of pyrolysis liquids. The linearity, sensitivity, precision, and recovery of photodiode array (PDA) detector, single-quadrupole mass spectrometer (MS), and evaporative light scattering (ELS) detector were compared for the quantitative determination of several typical compounds found in pyrolysis liquids. PDA and MS detectors were found to be suitable for the quantification of furans and phenol derivatives (furfural, vanillin, syringol), but sugars an…
Wood and Black Liquor-Based N-Doped Activated Carbon for Energy Application
The research was funded by the Latvian Council of Science project “Nanostructured Nitrogenated Carbon Materials as Promoters in Energy Harvesting and Storage Technologies”, project No LZP-2018/1-0194, “New biomass origin materials hybrid carbon composites for energy storage” project No LZP-2020/2-0019 and postdoc project “Nitrogen and phosphorus-containing biomass based activated carbons for fuel cells and supercapacitors” project No 1.1.1.2/VIAA/4/20/596.
Highly Porous Wood Based Carbon Materials for Supercapacitors
Wood based activated carbons synthesized by two-stage thermocatalytical synthesis with NaOH activator were studied and used as supercapacitor electrodes (sulphuric acid electrolyte). Porous structure and electrochemical properties of carbons vs synthesis conditions were assessed. It was found that there are correlations between carbons synthesis variables, their porosity and supercapacitors functional characteristics. At the temperature 600 o C and activator/precursor ratio 1.25 porosity decreased, however energy capacitance of supercapacitor increased calculating on elementary cell mass.