Optimization of Lignin Separation Process from Black Liquor Using Strong Acids and Supercritical CO₂

Natthatida Kunwong^1*, Navadol Laosiripojana¹, Verawat Champreda²

1. ¹The Joint Graduate School of Energy and Environment, King Mongkut’s University of Technology Thonburi, Bangkok 10140
2. ²National Center for Genetic Engineering and Biotechnology 113 Phahonyothin Rd ., Klong Luang, Pathumthani 12120, Thailand

Published in The First NZAAR International Event Series on Natural and Built Environment, Cities, Sustainability and Advanced Engineering, Putrajaya, Malaysia, 26 June 2016, pages 106 to 107. New Zealand Academy of Applied Research. ISSN 2463-5979 (online), 2463-5960 (print).

Abstract

Black liquor is the major waste from pulp and paper industry. Generally, it contains the amount of lignin fraction around 10-20% depending on the pulping process. The extracted lignin can be efficiently converted to several value-added products. In this work, lignin was comparatively extracted from black liquor by acidification and suband super-critical CO 2 . For the first method, lignin precipitation was achieved by decreasing alkali black liquor pH from 10 to 2 with strong acid (H 2 SO 4 and HCl) then filtrate with Glass fiber filter to separated solid and liquid phase. In the second technique, the acidification using CO 2 under sub and supercritical conditions which obtain pH 5 then use membrane to separated liquid and solid phase. The lignin precipitated percentages from each technique were measured and optimized for enhancing the highest yields of precipitated lignin.

Keywords: Lignin; Black liquor; Acidification process; supercritical CO 2; lignin Precipitation

Rights

Copyright © New Zealand Academy of Applied Research Ltd 2016. All rights reserved. Reproduced in the GDI Academy archive from the original proceedings without change to the authors’ text.