应用复合改性粉煤灰吸附尾矿浸出液中的Zn

以粉煤灰为基质、十六烷基三甲基溴化铵和NH4Cl为改性剂，通过湿法制备了复合改性粉煤灰，研究了改性粉煤灰对模拟和实际尾矿浸出液中Zn的吸附效果。通过单因素实验优化了改性粉煤灰去除模拟和实际尾矿浸出液中Zn的条件，用Langmuir方程和Freundlich方程较好的拟合了改性粉煤灰的等温吸附实验数据。改性粉煤灰的饱和吸附量为17.39 mg·g-1，在模拟和实际尾矿浸出液中，改性粉煤灰对Zn的去除率分别为96.8%和91.9%，与原粉煤灰相比均有显著增加。对于实际尾矿浸出液，通过正交实验优化的改性粉煤灰的最佳使用条件是：投加量2.5 g·（50 g）-1尾矿，反应温度25℃，pH≥4.0。模拟酸雨实验的结果表明改性粉煤灰适合在酸雨频发的地区使用。

Adsoprtion of zinc in tailings leaching solution by composite modified fly ash

In this study,a new modified fly ash (MFA) was prepared via a solution method,using the fly ash as raw material and two different compounds,hexadecyltrimethylammonium bromide and NH4Cl,as modifiers.The adsorption effects of zinc on the MFA in the simulated and experimental tailings leaching solution were investigated.The experimental conditions for the adsorption of Zn in the simulated and experimental tailings leaching solution were optimized using single-factor experiments,and the isothermal adsorption data of the MAF were finely fitted to the Langmuir and Freundlich equations.The saturated adsorption capacity of the MFA was 17.39 mg·g-1,and the removal rate of Zn by the MFA in the simulated and experimental tailings leaching solution were 96.8% and 91.9%,respectively,which were much higher than that of the original fly ash.In the experimental tailings leaching solution,the optimum conditions obtained from orthogonal experiments were:MAF with 2.5 g·(50 g)-1 tailings,reaction temperature of 25℃,and pH≥4.0.The simulated acid rain experiments showed that the MFA was suitable for use in the area where acid rain fell.