摘要：

采用一锅法制备MnO₂/MCM-41复合材料，探究其对放射性废水中Sr²⁺的去除。通过SEM、BET、FT-IR对复合材料进行了表征。探究MnO₂和MCM-41的质量比、pH、吸附时间、竞争离子效应等参数对其吸附性能的影响。结果表明，复合材料能迅速吸附水中Sr²⁺，并在120 min达到吸附平衡，最大吸附容量为85.46 mg/g。MnO₂和MCM-41的质量比为4∶1 时复合材料具有最高的吸附容量，在pH为4~9范围内复合材料具有较高的吸附性能，此外复合材料在Na⁺、K⁺、Mg²⁺、Ca²⁺存在的情况下依然保持良好的吸附容量，抑制吸附能力遵循Na⁺<K⁺<Mg²⁺<Ca²⁺的排序。吸附动力学分析伪二级模型比伪一级模型更能拟合吸附数据，说明化学吸附在吸附过程中占主导地位。所制备的MnO₂/MCM-41新型复合材料用于去除放射性废水中的Sr²⁺具有吸附迅速、吸附容量大、选择性强、能够大规模制备等优点，这使得其有望在含Sr²⁺放射性废水处理领域发挥重要作用。

关键词: 二氧化锰, MCM-41, 锶, 吸附, 水处理

Abstract:

MnO₂/MCM-41 composite was prepared by one-pot method to investigate its removal of Sr²⁺ from radioactive wastewater. The prepared composite were characterized by SEM，BET，FT-IR. The effects of parameters such as mass ratio，pH，adsorption time and competing ion effect of MnO₂ and MCM-41 on the adsorption test were investigated. The results showed that the composite adsorbent could rapidly adsorb Sr²⁺ in water and reached the adsorption equilibrium in 120 min with the maximum adsorption capacity of 85.46 mg/g. The composite adsorbent had the highest adsorption capacity when the mass ratio of MnO₂ and MCM-41 was 4∶1，and the composite adsorbent had high adsorption performance in the range of pH 4-9. In addition，the composite adsorbent maintained good adsorption capacity in the presence of Na⁺，K⁺，Mg²⁺ and Ca²⁺，and the inhibited adsorption capacity followed the order of Na⁺< K⁺< Mg²⁺< Ca²⁺. The adsorption kinetic data analysis of the pseudo-secondary model fit the adsorption data better than the pseudo-first-order model，indicating that chemisorption dominated the adsorption process. The novel MnO₂/MCM-41 composite prepared for the removal of Sr²⁺ from radioactive wastewater had the advantages of rapid adsorption，high adsorption capacity，selectivity，and the ability to be prepared on a large scale，which made it promising to play an important role in the field of Sr²⁺ containing radioactive wastewater removal.

Key words: manganese dioxide, MCM-41, strontium, adsorption, water treatment

中图分类号: 

• X703

• TQ426