Effect of hydrothermal pretreatment on hexenuronic acid content in unbleached kraft bamboo dissolving pulp
To investigate economically feasible and environmental friendly approach that reduce hexenuronic acid ( HexA ) of bamboo in paper industry, hot water pretreatment (HWP) and sulphate pulping method on the formation rule of HexA was studied. In addition, relationship between HexA content in unbleached pulp with xylan removal rate during HWP, Kappa number and pentosan content of pulp were also investigated. Results showed that HexA content of dissolving pulp decreased as duration of HWP prolonged, but HexA level did not significantly drop after being hot-water treated over 80 min. A slight decrease in HexA content was detected in kraft dissolving pulp that pretreated hot water was leached from bamboo before pulping. Within the range of alkaline addition between 15% and 21%, HexA content increased at first and then decreased after additive alkaline was over 19%. In consideration of Kappa number, xylan content of unbleached pulp, and chemical cost, HWP for 80 min with alkaline addition under 19% were the optimum processing condition, resulting in 90% reduction in HexA content with Kappa number of 15 that met the standard of kraft dissolving pulp.
hot water pretreatmentkraft dissolving pulphexenuronic acidKappa numberpentosan
国家科技期刊平台
NSTL
万方数据
维普
