蔗渣Soda-AQ浆二氧化氯脱木素效率研究及纸浆FT-IR分析

Studies of chlorine dioxide delignification efficiency on bagasse Soda-AQ pulp and its FT-IR spectrum analysis

研究了蔗渣Soda-AQ浆二氧化氯脱木素(D0)效率的影响因素,得到最佳脱木素工艺条件为ClO2用量0.8%,终点pH值范围为4.0～4.5,反应温度70℃,反应时间60min。在此基础上经D1P和D2P短序ECF漂白后(ClO2用量分别为0.8%和1.0%,H2O2用量2%),蔗渣浆白度分别达到80.2%和81.4%,且具有较好的物理强度。纸浆FT-IR谱图分析表明:蔗渣浆经ClO2脱木素后,纸浆中的羟基和羰基数量增多,愈疮木基和紫丁香基木素单元均受到一定程度的破坏,经H2O2进一步漂白后,木素结构中苯环的特征峰逐渐减弱以至消失,羰基等主要发色基团逐渐减少,纸浆白度得到提高。

Factors influencing chlorine dioxide delignification efficiency of bagasse Soda-AQ pulp were studied.Optimized delignification process variables were charge of ClO2 0.8%,range of final pH 4.0～4.5,and retention time 60 minutes at 70℃.Based on optimal delignification conditions above,the brightness of bleached bagasse pulp reached 80.2% and 81.4% respectively after bleached by two ECF short sequences of D1P and D2P with dosage of ClO2 0.8% and 1.0% respectively and charge of H2O2 2%.Simultaneously,good physical strength properties were maintained.FT-IR spectrum analysis of unbleached and bleached pulp indicate that some functional groups content increases after ClO2 delignification,such as hydroxyl and carbonyl,etc.Additionally,both guaiacyl units and syringyl units are degraded to some extent.With further H2O2 bleaching,the absorption of phenyl ring and ring-conjugated carbonyl gradually decreases and then disappeares.Main chromophores including carbonyl groups decreases and a high brightness of bleached pulp is achieved.