改性香蕉皮吸附剂对六价铬的吸附

摘要

Using modified banana peel to treat Cr(Ⅵ)-containing wastewater, the factors influencing the adsorption property of the said adsorbent for Cr (Ⅵ) were investigated, and its adsorption mechanism was preliminarily discussed. The results of the test showed that, the optimal condition for modified banana peel adsorbing Cr(Ⅵ) was as follows: the particle size of adsorbent was 90 mesh, the dosage was 1.8 rng/L, the pH value of the wastewater was 3, the initial mass concentration of Cr(Ⅵ) was about 5 mg/L, the oscillation time was 40 min, the oscillation speed was 150 r/min. Under the above condition, the removal rate of Cr(Ⅵ) by modified banana peel reached 91.5%. After the treatment, the residual Cr(Ⅵ) concentration in the effluent water was lower than the maximum permissible concentration of the first kind of pollutants discharge in GB 8978—1996 Integrated Wastewater Discharge Standard. The adsorption mechanism of modified banana peel for Cr (Ⅵ) could be well simulated by Henry adsorption isotherm.%采用改性香蕉皮吸附剂对含六价铬废水进行吸附处理,考察了吸附条件对改性香蕉皮吸附剂吸附六价铬的影响,初步探讨了其吸附机理.试验结果表明,改性香蕉皮对六价铬吸附的最佳条件是:吸附剂粒径为90目,投加量为1.8 mg/L,废水pH值为3,六价铬初始质量浓度约为5mg/L,振荡时间为40 min,振荡速率为150r/min,在此条件下改性香蕉皮对六价铬的吸附率为91.5％,处理后废水中的残余六价铬浓度小于GB 8978-1996《污水综合排放标准》中第一类污染物的允许排放浓度.改性香蕉皮对六价铬的吸附机理与亨利吸附等温式能较好地拟合.