05.02.2015
Research news
Dissertation news

Dissertation: 20 Feb 2015. Advanced Biorefinery Concepts Integrated to Chemical Pulping (Lehto)

Time:

20.2.2015 12:00 — 15:00


Location: Ylistonrinne, KEM4
Ph.Lic. Joni Lehto defends his doctoral dissertation in Applied Chemistry ”Advanced Biorefinery Concepts integrated to Chemical Pulping”. Opponent Professor Ali Harlin (VTT Technical Research Centre of Finland) and custos Professor Raimo Alen (University of Jyväskylä).

Joni LehtoPh.Lic. Joni Lehto defends his doctoral dissertation in Applied Chemistry ”Advanced Biorefinery Concepts integrated to Chemical Pulping”. Opponent Professor Ali Harlin (VTT Technical Research Centre of Finland) and custos Professor Raimo Alen (University of Jyväskylä).

The objectives of this study were to determine the effects of various aqueous acidic and alkaline pre-treatments on the main Nordic pulp woods and to determine the behavior of the pre-treated feedstocks during the subsequent alkaline sulfur-free pulping (soda-AQ and oxygen-alkali pulping). This research approach included pre-treatments performed with different wood species under various conditions as well as chemical characterization and fractionation of the pre-treatment hydrolysates, sulfur-free pulping of the pre-treated feedstocks, and analysis of the black liquors and produced pulps.

The results presented in this study clearly revealed the effects of applied pre-treatment conditions on the chemical composition of the hydrolysates. Whereas the acidic pre-treatments could be utilized for producing mainly carbohydrate-containing hydrolysates, the alkaline treatments produced mainly organic acids. Other main soluble components were dissolved lignin, furanoic compounds, and small-size phenolics. As rich sources of various organic components it could be concluded that pre-treatment liquors containing various organics could serve as potential raw material sources for the production of green chemicals utilizable in various applications.

In addition to the production of organics-containing hydrolysates suitable for further refining, the effects of acidic pre-treatments on the subsequent sulfur-free pulping operations were determined. Applying this stage prior to alkaline pulping, the content of residual lignin in pulps could be significantly decreased. In addition, the chemical composition of the formed spent liquors, black liquors, was clearly different when compared to reference cooks performed with without pre-treatments.

Publication:
Department of Chemistry, University of Jyväskylä, Research Report No. 180, 173 s., Jyväskylä 2015, ISBN 978-951-39-6066-7, ISSN 0357-346X.
Press copies: 0400-247976, leena.m.mattila@jyu.fi.



More information

Joni Lehto

Doctoral Student

None

joni.t.lehto@jyu.fi