纳米MnO_2/Fe_3O_4对镉离子的静态吸附

采用水热合成法将Mn O_2包覆于纳米Fe_3O_4的表面,制备出纳米Mn O_2/Fe_3O_4,并将其用于含镉溶液的吸附。考察了吸附效果的影响因素,并研究了纳米Mn O_2/Fe_3O_4的重复使用性能。实验结果表明:在初始镉离子质量浓度为10 mg/L、吸附剂投加量为4 g/L、吸附温度为20℃、溶液p H为6.0、吸附时间为12 h的条件下,镉离子去除率由使用纳米Fe_3O_4时的3%增至使用纳米Mn O_2/Fe_3O_4时的96%;在初始镉离子质量浓度为50 mg/L、纳米Mn O_2/Fe_3O_4投加量为4 g/L、吸附温度为20℃、溶液p H为6.0、吸附时间为1 h的条件下,镉离子去除率达78%,吸附量为9.7 mg/g;经5次重复使用后,纳米Mn O_2/Fe_3O_4对镉离子的去除率仅比首次使用时降低了10百分点,具有良好的重复使用性能。

Static adsorption of cadmium ions on nano MnO2/Fe3O4

MnO₂ was loaded on the surface of nano-Fe₃O₄ by hydrothermal synthesis method to prepare nano MnO₂/Fe₃O₄,which was used for adsorption of cadmium from solution. The factors affecting adsorption were investigated,and the reuse performance of nano MnO₂/Fe₃O₄ was researched_. The experimental results show thatUnder the conditions of initial cadmium ion mass concentration 10 mg/L,adsorbent dosage 4 g/L,adsorption temperature 20 ℃,solution pH 6 and adsorption time 12 h,the removal rate of cadmium ion is increased from 3% on nano-Fe₃O₄ to 96% on nano MnO₂/Fe₃O₄;Under the conditions of initial cadmium ion mass concentration 50 mg/L,nano MnO₂/Fe₃O₄ dosage 4 g/L,adsorption temperature 20 ℃,solution pH 6 and adsorption time 1 h,the removal rate of cadmium ion is 78%,and the adsorption capacity is 9.7 mg/g;After 5 times of reuse,the removal rate of cadmium ion on nano MnO₂/Fe₃O₄ is only reduces by 10 percentage point compared with that at the first use.