用高锰酸钾改性提高竹炭对Cu2+ 的吸附能力

采用KMnO₄溶液在回流状态下对竹炭进行改性，得到改性竹炭。比较研究了 KMnO₄浓度对Cu²⁺ 在竹炭上的吸附率-pH曲线的影响，并研究了KMnO₄改性对竹炭吸附和解吸Cu²⁺ 性能的影响。静态吸附试验表明， KMnO₄ 改性使竹炭对Cu²⁺ 吸附率-pH曲线及pH₅₀向低pH偏移，当 KMnO₄溶液浓度为0.04 mol/L时，改性效果最好； KMnO₄ 改性使其投加量节省约2倍； 竹炭对Cu²⁺ 的吸附均遵循Langmuir单分子层吸附规律， 在相同Cu²⁺ 平衡浓度下，改性后的竹炭对Cu²⁺ 的吸附量提高约53%，升高温度能明显提高改性竹炭对Cu²⁺ 的吸附能力，40 ℃的饱和吸附量是25 ℃的1.69倍。KMnO₄ 改性提高了竹炭从水中吸附重金属离子的能力，并改善了其解吸再生性能。

Cu2+ Adsorption Improvement of Bamboo Charcoal with KMnO4

Bamboo charcoal (BC) was treated with KMnO₄ solution under refluxing condition to prepare the new modified bamboo charcoal.The influence of KMnO₄concentration on the Cu²⁺ adsorption rate-pH curves and pH₅₀ was investigated.The modification with KMnO₄ affected the adsorption and desorption capacity of bamboo charcoal to Cu²⁺.The results show that the Cu²⁺ adsorption rate-pH curves and pH50 of bamboo charcoal move to low pH after modification with KMnO₄.The best result achieved at 0.04 mol/L KMnO₄.The modification with KMnO₄ improves the adsorption rate of Cu²⁺ and reduces the consumption of adsorbent about threefold than that of unmodified bamboo charcoal.The adsorption isothermals of Cu²⁺ over the modified and unmodified bamboo charcoal match to Langmuir monolayer adsorption.On the same condition of equilibrium concentration of Cu²⁺, the adsorption amount of Cu²⁺ over bamboo charcoal modified with KMnO₄ increases about 53% than that of the unmodified bamboo charcoal.Moreover, the Cu²⁺ adsorption capacity of the modified bamboo charcoal can be improved obviously with the increase of temperature.At 40 ℃, the saturated adsorption amount of Cu²⁺ is 169% as much as that of at 25 ℃.The modification of bamboo charcoal with KMnO₄ not only increases the adsorption capability of bamboo charcoal to heavy metal ions, but also improves the ability of desorption-regeneration of bamboo charcoal.