蔗渣硫酸盐浆的臭氧漂白

The Bleaching of Bagasse Sulphate Pulp with Ozone

本文介绍了蔗渣硫酸盐臭氧漂白的过程及其影响因素,并探讨了纤维表面状态及发色基团的变化。结果表明:臭氧漂白蔗渣硫酸盐浆宜采用40～50％的浆浓。臭氧的漂白效率很高,消耗1.5％臭氧可使白度提高近30度;酸预处理有助于提高臭氧漂白效率。臭氧漂白过程可分为两个阶段:前期,脱木素和自度提高同时进行;后期主要起漂白的作用。臭氧漂白使浆料的碳水化合物明显地降解,但对物理强度的影响不大。草酸等在漂白过程中具有较好的保护作用。臭氧处理蔗渣浆同样发生细纤维化现象。红外光谱显示了臭氧处理的浆料中出现较多的酯和羧基。

The ozone bleaching performance of bagasse kraft pulp is studied and compared with that of wood pulp in order to explain the ozone bleaching characteristics of bagasse kraft pulp. The results of the research indicated that the suitable consistency for bleaching bagasse kraft pulp with ozone is 45% or so.If the pulp is pretreated with sulfuric or acetic acid, the ozone bleaching efficiency increases obviously. The ozone bleaching course of bagasse kraft pulp is divided into two stages.In the earlier stage, ozone reacts with lignin, and then the lignin is removed. Delignification and bleaching effect take place simultaniously. In the later stage, ozone mainly destroys chromophoric group to brighten the pulp while the delig-nification is very weak. The degradation of carbohydrates during ozone bleaching of bagasse kraft pulp is significant. Oxalic acid can protect it. For ozone bleaching bagasse pulp evident fibrillation is observed by using SEM.IR analysis showed that ozone bleaching removed lignin and decreased chromophoric group in pulp. At the same time carboxyl groups and carboxylate probably produced.