响应面法优化铁尾矿砂对铜(II)的吸附条件

Optimization of Adsorption Conditions of Copper (II) on Ferrous Mill Tailings by Response Surface Methodology

以铁尾矿砂作为水体沉积物污染修复覆盖材料,研究了不同pH值、转速下铁尾矿砂对水相中Cu2+去除情况,得出水相pH值在3~5时有利于Cu2+去除率的提高;静态吸附与动态吸附相比有显著差异,转速为180 r/min时,铁尾矿砂对水相中Cu2+去除率最高。使用Box-Behnken设计了响应面试验,研究了水相pH值、温度、Cu2+初始浓度以及铁尾矿砂投加量4个因素对水相中Cu2+去除作用,建立了铁尾矿砂对水中Cu2+去除率的回归模型。其中各因素对响应值的影响次序为:温度>投加量>初始浓度>pH值。模型验证结果预测去除率与试验值偏差仅为0.08%,能够很好预测去除率变化情况。

The ferrous mail tailings (FMT) were applied in an in-situ restoration for copper (II) in water,the pH and rotation rate were investigated which effected removal rate.The result showed that removal rate was promoted apparently in pH 3 to 5 and also rotation rate in 180 r/min.The factors such as pH,temperature,initial copper(II) concentration,and adsorbent dosage were investigated by Box-Behnken in response surface methodology,mathematical models were established,and also the effectiveness of the model was verified.Evaluation of the effects of different factors on the removal rate showed that the effects followed the trend:temperature,adsorbent dosage,initial copper (II) concentration,and pH in descending order.The optional conditions for absorption progress involved a temperature of 20℃,initial pH of 4,and initial copper (II) concentration of 250 mg/L,and adsorbent dosage of 15 g/L.Under the aforementioned conditions,the removal rate is 88.80%,which is closed to the predicated removal rate of 88.87%.Therefore,the model established can truly reflect of those main factors.