Kinetics Analysis of Wheat Straw Pulping Process

Abstract:

This paper analyzes the delignification mechanism of wheat straw pulping process. The lignin removal of pulping process is left in black liquor. The higher the black liquor lignin content is, the bigger the lignin of paper pulp is removed. The relations of black liquor lignin content and alkali concentration to pulping time are described in detail. The results show that delignification process is divided into two stages: quick and slow stage. The lignin removal rate in the first stage is much higher than the second, that is, lignin has been removed more sufficiently after quick stage. In first stage, reaction order of delignification is 1.0, and 0.7 with respect to OH-, the activation energy is 38.62 kJ • mol-1. The latter delignification also belongs to the first-order reaction and 4.4 with respect to OH-, the activation energy is 75.56 kJ • mol-1. Apparently, slow stage needs to consume large amounts of energy to removal lignin.

• Periodical: Advanced Materials Research (Volumes 860-863)
• Pages: 1012-1016
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.860-863.1012
• Online since: December 2013
• Authors: Ming Xian Cui, Wei Song, Zong Yu Liu
• Keywords: Black Liquor, Delignification, Kinetic, Wheat Straw Pulp

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