氯化锌法制备木质素活性炭的研究

Study on Preparation of Lignin Activated Carbon with Zinc Chloride

[目的]优化氯化锌制备高性能活性炭的操作参数。[方法]以从棉浆黑液中提取的酸析木质素为原料,采用氯化锌活化法制备木质素活性炭,并以得率和碘吸附值为考察指标,选择氯化锌浓度等4个因素进行正交试验,确定最佳工艺条件。[结果]4因素对氯化锌制备活性炭的影响依次为:陈放温度>陈放时间>浸渍比>氯化锌浓度;最佳工艺条件为:陈放时间12 h、陈放温度120℃、浸渍比1∶3、氯化锌溶液浓度40%、活化温度600℃、活化时间70 min、升温速率10℃/min;制备的活性炭得率为46.39%、碘吸附值839.68 mg/g、亚甲基蓝吸附值5.5 ml/0.1g、A法焦糖脱色率120%、水分4.81%、灰分5.29%。[结论]用氯化锌活化法制备棉浆木质素活性炭方法简单,节约资源,减少环境污染,具有广泛的应用前景。

[Objective] The study aimed to optimize the operating parameters for preparation of high performance activated carbon with zinc chloride. [ Method] With lignin acidifying precipitation extracted from cotton pulp black liquid as material, the lignin activated carbon was prepared by using activation method of zinc chloride, with yield rate and iodine value as the reference index, 4 factors of zinc chloride conch, etc. were selected for orthogonal test to determine the best technology conditions. [ Result] The influence of 4 factors on preparation of activated carbon with zinc chloride in order was： laying temperature 〉 laying time 〉 immersion ratio 〉 zinc chloride concn. The best technology conditions were： laying time of 12 h, laying temperature of 120 ℃, impregnation ratio of 1：3, concn, of zinc chloride of 40%, activation temperature of 600 ℃, activation time of 70 min. and heating rate 10 ℃/min; The yield of prepared active carbon was 46.39%, iodine value was 839.68 mg/g, the absorption value of methylene blue was 5.5 ml/0.1g, the decolorization of caramel A was 120%, with moisture content of 4.81% and ash content of 5.29%. [Conclusion] The method for preparing the lignin activated carbon of cotton pulp with zinc chloride activation was simple, with saving resource and decreasing environment pollution, which had extensive application prospect.