杨木NS-AQ法高得率化学浆氧脱木素前的DTPA预处理

对杨木NS AQ法高得率化学浆氧脱木素前的DTPA预处理进行了研究。结果表明 ,DTPA预处理对浆的性质有一定影响 ,在pH值 1～ 9范围内 ,随着 pH值的提高 ,浆的白度逐渐下降 ,卡伯值和黏度也有一定变化 ,并在pH值 7处有峰值。DTPA预处理的适宜条件是 :pH值 3,时间 30min ,温度 4 0℃ ,浆浓 15 % ,用量 2 .5 %。预处理使氧脱木素的反应选择性提高 ,卡伯值下降 12 % ,黏度提高 4 .7% ,白度提高 5 .4 %。

The Pretreatment with DTPA before Oxygen Delignification for the NS-AQ High Yield Chemical Pulp of Aspen

This paper studies on the pretreatment with DTPA before oxygen delignification for the NS-AQ high yield chemical pulp of aspen. The results indicate that the pretreatment influence certainly the properties of pulp. Within the pH1-9, as the pH value raising the brightness of pulp decrease gradually, Kappa number and intrinsic viscosity change certainly too, and both have peak value at pH7. The suitable conditions of pretreatment are: pH3, time 30min., temperature 40℃, consistency 15%, the charge of DTPA 0.25. The reaction selectivity of oxygen delignification is increased by pretreatment: the Kappa number decrease by 12%, the intrinsic viscosity increase by 4.7%, and the brightness of pulp increase by 5.4 per cent.