高锰酸钾改性对颗粒活性炭吸附Cu2+的影响

采用KMnO₄溶液在回流状态下对颗粒活性炭进行了改性。考察了KMnO₄ 溶液浓度对Cu²⁺吸附率-pH曲线及pH的影响，并研究了KMnO₄ 改性对颗粒活性炭吸附和解吸Cu²⁺性能的影响。结果表明，KMnO₄ 改性使颗粒活性炭对 Cu²⁺吸附率-pH曲线及pH向低pH偏移。当KMnO₄溶液浓度为0.03 mol/L时，改性颗粒活性炭效果最好；KMnO₄ 改性提高了颗粒活性炭对Cu²⁺的吸附速率，使其投加量节省约3倍；Cu²⁺在改性及未改性活性炭上的吸附遵循Freundlich等温吸附方程，在相同Cu²⁺平衡浓度下，KMnO₄改性活性炭对 Cu²⁺的吸附量提高约 2.7倍；使用 0.35 mol/L的HCl溶液作解吸液，Cu²⁺从KMnO₄改性活性炭上的解吸率为 91.1%，而Cu²⁺从未改性活性炭上的解吸率仅为8.8%。KMnO₄ 改性提高了颗粒活性炭从水中吸附重金属离子的能力，并促进了其解吸再生性能。

Effect of Modification with KMnO4 on the Cu2+Adsorption of Granular Activated Carbon

Granular activated carbon was modified with KMnO₄ at refluxing. The influence of KMnO₄ concentration on the Cu²⁺ adsorption rate-pH curves and pH was investigated and the effect of the modification with KMnO₄ on the Cu²⁺ adsorption and desorption capacities of activated carbon was studied. The results show that the Cu²⁺ adsorption rate-pH curves and pH of activated carbon move to the lower pH side after modification with KMnO₄. The best result is achieved at 0.03mol/L KMnO₄ concentration. The modification with KMnO₄ has improved the adsorption rate of Cu²⁺ and reduced the consumption of adsorbent by three times compared with that of unmodified carbon. The Cu²⁺ adsorption on the modified and unmodified activated carbon conforms to the Freundlich isothermal adsorption equation. At a same equilibrium concentration of Cu²⁺, the Cu²⁺ adsorption amount on the activated carbon modified with KMnO₄ is about 2.7 times higher than that on unmodified carbon. When 0.35mol/L HCl solution is used as elution solution, the desorption rates of Cu²⁺ on the KMnO₄ modified activated carbon and unmodified activated carbon are 91.1% and 8.8% respectively. The modification with KMnO₄ has not only increased the adsorption capacity of granular activated carbon for heavy metal ions, but also improved its desorption-regeneration performance.