K/Zn/Sn/S金属硫化物对水中铯离子的吸附去除性能及机理  

Adsorptive removal performance and mechanism of cesium ion from aqueous solutions by a K/Zn/Sn/S metal sulfide

作　　者：洪奇圣 穆景利 张艳[1,2,3] 袁宗胜 杨丽阳 张铭栋 HONG Qisheng;MU Jingli;ZHANG Yan;YUAN Zongsheng;YANG Liyang;ZHANG Mingdong(College of Environment&Safety Engineering,Fuzhou University,Fuzhou 350108,China;College of Geography and Oceanography,Minjiang University,Fuzhou 350108,China;Fuzhou Institute of Oceanography,Fuzhou 350108,China)

机构地区：[1]福州大学环境与安全工程学院,福州350108 [2]闽江学院地理与海洋学院,福州350108 [3]福州海洋研究院,福州350108

出　　处：《环境工程学报》2024年第1期1-12,共12页Chinese Journal of Environmental Engineering

基　　金：国家自然科学青年基金资助项目(52200096);福建省自然科学基金青创项目(2021J05209);闽江学院高层次人才科研启动经费(32204304)。

摘　　要：通过水热法合成了纳米片状K/Zn/Sn/S金属硫化物(KZTS-NS),并研究了KZTS-NS对Cs^(+)的吸附特性及机理。结果表明,KZTS-NS具有快速的吸附Cs^(+)动力学特性,仅需10 min即可达到吸附平衡,此时Cs^(+)去除率为96.50%;KZTS-NS对Cs^(+)的吸附等温线符合Langmuir模型,最大吸附容量为133.96 mg·g^(-1),高于报道的其他吸附剂,且吸附是个自发、吸热且熵增的过程;KZTS-NS能够在pH为3~10内对Cs^(+)保持良好吸附效果;溶液中共存离子对KZTS-NS吸附效果的影响从高到低排序依次为Mg^(2+)>Ca^(2+)>Na^(+)>K^(+),在自来水中、矿泉水、湖水和海水中KZTS-NS对Cs^(+)的去除率分别为42.14%、25.15%、14.14%和4.44%。此外,利用扫描电子显微镜(SEM)、X射线衍射(XRD)和X射线光电子能谱(XPS)等技术对吸附铯离子(Cs^(+))前后的KZTS-NS进行表征以揭示吸附机理。结果表明,KZTS-NS具有纳米片形貌,K、Zn、Sn和S元素在表面均匀分布,吸附Cs^(+)后形貌保持不变,并且XRD特征峰往低角度方向偏移,对应的晶面间距增大;由XPS图谱和定量分析可知,KZTS-NS对Cs^(+)的吸附机理为离子交换。总之,KZTS-NS能够快速、高效地去除废水中的Cs^(+),具有较大的应用潜力。本研究将为放射性废水中Cs^(+)的处理提供技术参考和基础数据支撑。A nanosheet-like K/Zn/Sn/S metal sulfide(KZTS-NS) was synthesized by a hydrothermal method.The adsorption properties and mechanism of KZTS-NS towards Cs^(+) was investigated.The results showed that fast adsorption of Cs^(+) occurred by KZTS-NS with an equilibrium time of only 10 minutes and Cs^(+) removal rate of 96.50%.The adsorption isotherms were well fitted with the Langmuir model,and the calculated maximum adsorption capacity reached 133.96 mg·g^(-1),which was higher than other reported adsorbents.The adsorption of Cs^(+) by KZTS-NS was a spontaneous,endothermic,and entropy-increasing process.KZTS-NS had a good performance on Cs^(+) adsorption in the pH range of 3-10.The inhibitory effect of coexisting ions on Cs^(+)adsorption by KZTS-NS followed the sequence of Mg^(2+)>Ca^(2+)>Na^(+)>K^(+).The removal rates of Cs^(+) by KZTS-NS in tap water,mineral water,lake water,and seawater were 42.14%,25.15%,14.14%,and 4.44%,respectively.The KZTS-NS before and after cesium ion(Cs^(+)) adsorption was characterized using scanning electron microscopy(SEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS),etc.to reveal the Cs^(+)adsorption mechanism.Results showed that the nanosheet-like morphology of KZTS-NS remained unchanged before and after adsorption of Cs^(+).K,Zn,Sn,and S elements were evenly distributed on the surface of KZTS-NS.The XRD characteristic peaks after Cs^(+) adsorption shifted towards a lower 2θ value,corresponding to an increase in crystal plane spacing.The XPS spectra and quantitative analysis indicated that the adsorption mechanism of KZTS-NS for Cs^(+) was ion exchange.In summary,KZTS-NS could rapidly and efficiently remove Cs^(+) from wastewater and showed a great potential for further application.This study provides a technical reference and the basic data supports for the treatment of wastewater containing radioactive Cs^(+) ions.

关 键 词：金属硫化物 吸附 铯 放射性污染 离子交换 

分 类 号：X703[环境科学与工程—环境工程]