Impact of hardwood species chemical structures upon lignin and carbohydrate degradation

摘要

Most of the studies determining hardwood delignification rate and carbohydrate degradation focus upon understanding the behavior of a single wood specie. These studies tend to determine either the delignification rate or the rate of carbohydrate degradation without examining the potential interactions resulting from the non-studied variable. The current study performs a comprehensive evaluation on both lignin and carbohydrate degradation during kraft pulping of multiple hardwood species. The kraft delignification rate of E. urograndis, E. nitens, E. globulus, sweet gum, maple, red oak, red alder, cottonwood, and acacia were obtained. Furthermore, the kinetics of glucan, xylan and total carbohydrate dissolution during the bulk phase of the kraft pulping process for the above species were also investigated. The wide range of delignification and carbohydrate degradation rates were correlated to wood chemical characteristics. It appears that the S/G ratio and lignin-carbohydrate-complexes (LCCs) are the main characteristics responsible for the differences in kraft pulping performance among the hardwoods studied.