Acid Precipitation of Kraft Lignin from Aqueous Solutions: The Influence of pH, Temperature, and Xylan
Journal article, 2019
In this study, the manners in which temperature (45–77 °C) and the addition of xylan (5 g/95 g lignin) influence the onset of precipitation and evolution of the particle size distribution during acid precipitation of softwood kraft lignin were investigated in situ. No systematic trend between the onset pH of precipitation and the temperature or the addition of xylan could be observed at these conditions: the average onset pH was found to be 9.3. However, the size of the agglomerates increased as the temperature was increased, but added xylan rendered a decrease in agglomerate size. A higher onset pH was measured at increased Na ion concentration. The results indicate that the ionization degree of the phenolic groups influences the precipitation at 1 M Na ions but it is also probable that the degree of ionization of the carboxylic groups (on kraft lignin and xylan) influences precipitation (particle numbers and sizes).
particle size distribution
xylan
kraft lignin
Acid precipitation
Author
Tor Sewring
Wallenberg Wood Science Center (WWSC)
Chalmers, Chemistry and Chemical Engineering, Chemical Technology
Julie Durruty
Chalmers, Chemistry and Chemical Engineering, Chemical Technology
Lynn Schneider
Chalmers, Chemistry and Chemical Engineering
Helen Schneider
Chalmers, Chemistry and Chemical Engineering
Tuve Mattsson
Chalmers, Chemistry and Chemical Engineering, Chemical Technology
Wallenberg Wood Science Center (WWSC)
Hans Theliander
Wallenberg Wood Science Center (WWSC)
Chalmers, Chemistry and Chemical Engineering, Chemical Technology
Journal of Wood Chemistry and Technology
0277-3813 (ISSN) 1532-2319 (eISSN)
Vol. 39 1 1-13Areas of Advance
Energy
Subject Categories
Chemical Engineering
DOI
10.1080/02773813.2018.1488870