消除法制备低氯漂白紫胶及机理
发布时间：2018-09-03 18:30
【摘要】：在漂白紫胶乙醇溶液中加入乙醇钠(一种亲核试剂),选择性与紫胶分子中结合氯的碳原子反应,脱除漂白紫胶中的氯,制备了低氯漂白紫胶。研究乙醇钠加入量、反应温度和反应时间对脱氯效果的影响。结果表明:100g漂白紫胶中加入4.2g的乙醇钠,在90℃反应90min脱氯效果最佳;最佳反应条件时,产品中氯的质量分数为0.28%,远低于脱氯前的2.6%。紫外光谱分析表明,漂白紫胶最大吸收峰的波长由236nm蓝移至222nm,脱除结合氯后最大吸收峰的波长值恢复。通过亲核消除反应,乙醇钠能脱除漂白紫胶的结合氯,漂白紫胶脱氯前后的结构不同。
[Abstract]:Low chlorine bleaching lac was prepared by adding sodium ethoxide (a nucleophilic reagent) into the bleached lac alcohol solution and selectively reacting with the carbon atom of chlorine binding in the lac molecule to remove the chlorine from the bleached lac. The effects of sodium alcohol addition, reaction temperature and reaction time on dechlorination were studied. The results showed that the best dechlorination effect of 90min was obtained by adding 4.2 g sodium alcohol to the bleached lac at 90 鈩，
本文编号：2220811
[Abstract]:Low chlorine bleaching lac was prepared by adding sodium ethoxide (a nucleophilic reagent) into the bleached lac alcohol solution and selectively reacting with the carbon atom of chlorine binding in the lac molecule to remove the chlorine from the bleached lac. The effects of sodium alcohol addition, reaction temperature and reaction time on dechlorination were studied. The results showed that the best dechlorination effect of 90min was obtained by adding 4.2 g sodium alcohol to the bleached lac at 90 鈩，
本文编号：2220811
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