天然膨润土还原吸附Cr（Ⅵ）

以天然膨润土为吸附剂，还原吸附处理含Cr（Ⅵ）模拟废水。实验结果表明：以（NH₄）₂FeSO₄为还原剂吸附效果最佳；在还原剂加入量为理论值的0.8倍、膨润土加入量为6 g/L、吸附时间为30 min、吸附温度为30 ℃、初始Cr（Ⅵ）质量浓度为1 mg/L的条件下，Cr（Ⅵ）去除率可达99.6%，处理后模拟废水中总铬质量浓度低至0.003 mg/L。天然膨润土对Cr（Ⅵ）的还原吸附符合准二级动力学模型及Freundlich等温吸附模型。

Reduction Adsorption of Cr(Ⅵ) on Natural Bentonite

Natural bentonite was used as adsorbent in the reduction adsorption treatment of simulated Cr(Ⅵ)-containing wastewater. The experimental results show that：When (NH₄)₂FeSO₄ is used as reducing agent，the adsorption effect is the best；When the dosage of reducing agent is 0.8 time of the theoretical value，the dosage of bentonite is 6 g/L，the adsorption time is 30 min，the adsorption temperature is 30 ℃ and the initial Cr(Ⅵ) mass concentration is 1 mg/L，the Cr(Ⅵ) removal rate can reach 99.6% and the total Cr mass concentration of the treated wastewater can be as low as 0.003 mg/L. The reduction adsorption of Cr(Ⅵ) on natural bentonite accords with pseudo-second-order kinetic model and Freundlich isothermal adsorption model.