MnO2改性赤泥基多孔陶瓷滤料去除重金属离子的研究

电镀废水中重金属对水体的污染日益严重,如何安全处置重金属已成重要的研究课题.本文采用溶胶-凝胶法,在赤泥基多孔陶瓷滤球上涂覆MnO2膜,用于去除电镀废水中的Pb^2＋、Cd^2＋.研究了滤料改性膜热处理制度对膜与赤泥基多孔陶瓷滤球的结合性及对重金属离子去除率的影响,探讨了pH值、吸附时间、赤泥基环境修复材料的用量对去除率的影响.结果表明,改性陶瓷滤料最佳热处理温度为650℃时,时铅离子、镉离子去除能力最强.当MnO2改性滤料的添加量为2g、Pb^2＋的浓度为2mg/L、pH值为7、吸附时间为120min时,对Pb^2＋去除率可达96.75％;当MnO2改性滤料的添加量为2g、Cd2＋的浓度为2mg/L、pH值为7、吸附时间为120min时,对Cd2＋去除率可达96.73％.采用SEM、TG-DTA等现代测试技术对样品的结构及性能进行了表征,探讨了赤泥基多孔陶瓷滤球上涂覆MnO2膜的赤泥基环境修复材料的成膜机理和去除重金属铅离子、镉离子的作用机理.

MnO2-Modified Red Mud-based Porous Ceramic Filter for Removal of Heavy Metal Ions

With the growing heavy metal pollution from electroplating wastewater, the safe disposal of heavy metals has become an important research topic. In this study, the red mud porous ceramic filtration balls were coated with MnO2 film to remove Cd^2＋ and Pb^2＋ ions in electroplating wastewater. The effect of heat treatment on the membrane fit for the porous ceramic ball as well as the removal rate was studied. The influence of pH, adsorption time, and the amount of red mud-based environment rehabilitation material on the removal rate was also studied. The results show that the red mud-based environment rehabilitation material which was heated at 650℃ has the strongest ability to remove Cd^2＋ and Pb^2＋. When the Pb^2＋ concentration was 2mg/L, the pH value was 7, the adsorption time was 120min, and the dosage of MnO2 was 2g, the removal rate was 96.75%. When the Cd^2＋ ion concentration was 2mg/L, the pH value was 7, the adsorption time was 120min, and the dosage of MnO2 was 2g, the removal rate was 96.73%. The microstructure and properties of the samples were characterized by SEM, TG-DTA and other modern testing techniques. The mechanisms for membrane forming and the removal of Cd^2＋ and Pb^2＋ ions by MnO2 membrane on red mud-based environmental rehabilitation material were studied.