STUDY ON PRETREATMENT OF OXYGEN DELIGNIFICATION OF LARCH AS-AQ PULP
Pretreatment of oxygen delignification can improve the reactive selectivity, pulp strength, brightness and its stability. In this paper, pretreatment of oxygen delignification of larch AS-AQ pulp was studied. The chemical reagents applied to pretreatment included concentrated sulphuric acid, DTPA, Peracetic acid, acidic hydrogen peroxide and concentrated nitric acid. The results showed that the pretreatment before oxygen bleaching could improve delignification reaction, kappa value decreased obviously for all of the processes. The effect of acidic hydrogen peroxide on oxygen delignification was better than that of others. When the pretreated conditions were H2O2 3％, consistency 10％, 70 , 40min, oxygen delignification ℃ not only brought the pulp with lower kappa value 8.7 from original 38.2, but also kept the relatively higher carbohydrate contents, viscosity only decreased to 922 ml/g from 1132ml/g of primary pulp. Meanwhile, the brightness increased considerably to 58.1 ％ISO from 40.3 ％ISO. Compared with the result of single oxygen delignification (kappa value 12.0, viscosity 982 ml/g, brightness 52.6 ％ISO), the characteristic of pulp improved significantly.
pretreatment oxygen delignification larch AS-AQ bleaching
Jiang Yanqing Han Ying Xu Longquan
The College of Chemical & Material, Dalian Polytechnic University, Dalian, 116034, China
国际会议
广州
英文
503-505
2010-11-08（万方平台首次上网日期，不代表论文的发表时间）