层结构硫代锡酸盐的制备及去除痕量Cs^+离子  

Preparation of Layer Structure Thiostannate and Removal of Trace Cs^+

作　　者：那平[1] 孙千益 李呈呈 韩晴玉 王榕静 李萌[1] 吕慧芸 Na Ping;Sun Qianyi;Li Chengcheng;Han Qingyu;Wang Rongjing;Li Meng;Lü Huiyun(School of Chemical Engineering and Technology,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学化工学院

出　　处：《天津大学学报（自然科学与工程技术版）》2019年第12期1322-1328,共7页Journal of Tianjin University：Science and Technology

基　　金：国家自然科学基金资助项目(U1407116,21511130020,21276193)~~

摘　　要：137Cs是长半衰期的放射性核素,高效去除核废料中的137Cs对于核安全储存是必要的.针对金属硫化物对痕量Cs^+离子吸附能力不足等问题,探索了引入H元素对硫代锡酸盐的元素组成和吸附性能的影响因素.通过材料的一系列表征和吸附实验,研究了H元素引入量对材料的晶体结构、元素含量、Cs^+离子去除率以及吸附容量的影响.SEM和TEM表明,材料形貌为多层结构,微观尺寸达到10μm.EDS和XRD表明,引入H元素后明显提高了硫代锡酸盐的S和K元素含量,提高了Cs^+离子吸附性能.其中具有最佳配比硫代锡酸盐的S和K元素含量分别提高至39.6%和14.9%,并发现随着材料内H元素含量增加,K元素含量、晶面间距以及晶体体积减小.Raman和XPS证实材料是由[SnS6]八面体基本骨架组成,H和K元素作为平衡电荷.通过吸附实验考察了材料的Cs^+离子吸附性能.结果表明:H元素的引入能够显著提高硫代锡酸盐的Cs^+离子吸附性能,其中具有最佳配比的硫代锡酸盐在5 min内快速完成Cs^+离子吸附,去除率为97.7%;材料的Cs^+离子吸附过程符合Langmuir等温吸附模型,其中饱和吸附容量最高达到372 mg/g.该材料具有环境友好、低成本、易于合成以及高效的Cs^+离子吸附能力等特点,有望应用于核废料处理.137Cs is one of the radionuclides having a long half-life.Therefore,efficient removal of 137Cs from nuclear waste is necessary for safe nuclear storage.Metal sulfides have some drawbacks,such as an insufficient ability to remove Cs^+ions.In this study,thiostannate containing H was explored for its elemental composition and adsorption performance,and the effects of H on the crystalline structure,element content,and Cs^+ion removal rate and adsorption capacity were also studied through characterization and ion exchange experiments.SEM and TEM showed that the materials were of a typical multi-layer morphology,and microcosmic size was up to 10μm.EDS and XRD showed that the contents of S and K clearly increased with the introduction of H,and the adsorption performance of Cs^+ions improved.The best proportional contents of S and K in the thiostannate increased to 39.6%and 14.9%,respectively.Additionally,it was determined that with increasing H content in the materials,the content of K,crystal plane spacing,and crystal volume decreased.Raman and XPS confirmed that the material comprised[SnS6]octahedra to form the basic skeleton,and H and K acted as an equilibrium charge.Ion adsorptive properties of the Cs^+were investigated using Cs^+adsorption kinetics and ion exchange capacity experiments.Results showed that the Cs^+ion adsorption performance in thiostannate significantly improved with the introduction of H,and the thiostannate containing the best proportion quickly completed Cs^+ion adsorption within 5 min,with a removal rate of 97.7%.Cs^+ion adsorption of materials was in accordance with the Langmuir isothermal adsorption model,and the Langmuir fitting adsorption capacity was up to 372 mg/g.The material exhibited efficient Cs^+ion adsorption properties;further,the eco-friendly,low-cost,and facile synthesis underscored its potential in treating nuclear waste.

关 键 词：硫代锡酸盐 结构调控 吸附 铯 核废料处理 

分 类 号：TQ425.22[化学工程]