H6P2W18O62/MIL-101(Fe)材料的制备及其吸附性能

采用溶剂热合成法在制备MIL-101(Fe)的过程中引入杂多酸H_6P_2W_(18)O_(62),制备出吸附剂H_6P_2W_(18)O_(62)/MIL-101(Fe),并测试了其对亚甲基蓝(MB)的吸附性能。考察了H_6P_2W_(18)O_(62)的负载量、MB质量浓度、溶液pH、温度等对材料的吸附性能。通过XRD、SEM、FTIR、N2吸附-脱附等手段对材料进行表征。结果表明:吸附平衡前,吸附量随MB质量浓度的增加而增加,在溶液pH=4、H_6P_2W_(18)O_(62)负载量相对于复合物质量分数为35%的条件下,吸附剂H_6P_2W_(18)O_(62)/MIL-101(Fe)对亚甲基蓝溶液吸附效果最佳,在303K下H_6P_2W_(18)O_(62)/MIL-101(Fe)对MB的最大吸附量可达148.1 mg/g。通过动力学和热力学分析,该吸附过程符合拟二级动力学与Langmuir等温吸附模型,同时是一个吸热、自发的过程。

Preparation and Adsorption Properties of H6P2W18O62/MIL-101(Fe)

The heteropoly acid H6P2W18O62 was introduced into the MIL-101(Fe) by solvothermal synthesis to prepare a new adsorbent H6P2W18O62/MIL-101(Fe), and its adsorption performance for methylene blue (MB) was tested. The adsorption properties of the materials under different conditions such as the loading of H6P2W18O62, the mass concentration of methylene blue solution, the pH value of the solution and the temperature were investigated. The materials were characterized by XRD, SEM, FTIR and N2 adsorption-desorption. The experimental results show that the adsorption capacity increased with the increase of the mass concentration of MB before the adsorption equilibrium, when the loading amount of H6P2W18O62 is 35% of the mass fraction of the composite, the adsorption effect of the adsorbent H6P2W18O62/MIL-101(Fe) on methylene blue solution was the best in solution pH=4. The maximum adsorption capacity of MB by H6P2W18O62/MIL-101(Fe) can reach 148.1 mg/g at 303k. By kinetic and thermodynamic analysis, the adsorption process conforms to the pseudo-second-order kinetics and Langmuir isothermal adsorption model. The adsorption is also an endothermic and spontaneous process.