MnO2/TiO2改性沸石去除矿井水中Fe2+和Mn2+的试验研究

针对矿井水中Fe2+、Mn2+浓度超标及处理效果不稳定等问题，通过溶胶-凝胶法将纳米MnO₂和纳米TiO₂负载于天然斜发沸石表面制备出MnO₂/TiO₂改性沸石滤料，并分析了沸石改性前后的微观形貌和孔隙结构. 采用单因素动态吸附试验和Thomas模型拟合探究了MnO₂/TiO₂改性沸石对模拟矿井水水样中Fe2+、Mn2+的去除效果及机理，并考察水流速度、滤层厚度、溶液pH及硬度对去除效果的影响. 结果表明:较天然沸石而言，MnO₂/TiO₂改性沸石的比表面积、孔径、孔体积和阳离子交换量明显增大. 当水流速度为7 m/h、进水pH为9.5、水质硬度为350 mg/L、滤层厚度为110 cm时，改性沸石对Fe2+、Mn2+的最大吸附量分别为44.810、6.549 mg/g，且Thomas模型能较好地拟合改性沸石对Fe2+、Mn2+的吸附动力学特征. 反冲洗试验结果表明，反冲洗强度为13 L/(m2·s)，反冲洗时间大于7 min时，改性沸石的再生效果良好，可重复使用. 研究显示，本文制备的MnO₂/TiO₂改性沸石吸附滤料可为同步去除矿井水中Fe2+、Mn2+污染提供一种解决办法. 

Removal of Fe2+ and Mn2+ from Mine Water by MnO2/TiO2 Modified Zeolites

In order to solve the problems that the concentrations of Fe2+, Mn2+ in mine water exceed the standard, and the existing treatment is unstable, an adsorption filter material was prepared by loading nano-MnO₂ and nano-TiO₂ on the surface clinoptilolites via a sol-gel method. The microscopic morphology and pore structure of natural clinoptilolites and modified zeolites were compared. Meanwhile, the removal efficiency and removal mechanism of Fe2+ and Mn2+ in simulated mine water samples by the MnO₂/TiO₂ modified zeolites were explored through single factor dynamic adsorption tests and the Thomas model fitting. The influencing factors on the removal efficiency including water flow rate, filter layer thickness, initial pH and water hardness were studied. The results showed that compared to the natural clinoptilolites, the specific surface area, pore size, pore volume and cation exchange capacity of the MnO₂/TiO₂ modified zeolites were increased significantly. When the water flow rate was 7 m/h, the pH was 9.5, the water hardness was 350 mg/L, and filter layer thickness was 110 cm, the maximum dynamic adsorption capacities of the modified zeolites for Fe2+ and Mn2+ reached 44.810 and 6.549 mg/g, respectively. The adsorption kinetic characteristics of the modified zeolites for Fe2+ and Mn2+ could be well described by the Thomas model. The results of backwash experiments showed that when the backwash intensity was 13 L/(m2·s) and the backwash time was more than 7 min, the regeneration effect of the modified zeolites was satisfactory and the modified zeolites could be reused. Therefore, the MnO₂/TiO₂ modified zeolites prepared by this study can provide an efficient solution for treatment of Fe2+ and Mn2+ in mine water.