层状硫化物K_(2x)Mn_xSn_(3-x)S_6与Th(Ⅳ)的离子交换性能研究  

Ion-Exchange of Layered Metal Sulfide K_(2x)Mn_xSn_(3-x)S_6(KMS-1) with Th(Ⅳ)

作　　者：侯艳巧 罗明标[1] 刘建亮[1,2] 徐晶晶[3] 

机构地区：[1]东华理工大学核资源与环境国家重点实验室培育基地 [2]中国人民解放军91280部队 [3]中国矿业大学矿山生态安全教育部工程研究中心

出　　处：《稀有金属》2014年第3期412-418,共7页Chinese Journal of Rare Metals

基　　金：江西省教育厅科技项目(GJJ12379);国家自然科学基金项目(21261001)资助

摘　　要：采用水热法获得制备层状硫化物K2xMnxSn3-xS6(KMS-1),用扫描电镜(SEM),X射线衍射仪(XRD),傅里叶红外光谱仪(FTIR)对其形貌及结构进行表征。结果表明制备的KMS-1为层状结构,具有良好的晶体结构。采用静态批式法考察了接触时间、温度、Th(IV)起始浓度,溶液pH、Na+浓度等因素对KMS-1与Th(IV)的离子交换的影响。结果表明,pH值对KMS-1与Th(IV)的离子交换反应有显著影响,吸附容量随着溶液pH的增大而增大,且当pH>4时吸附容量不再随pH的变化而变化,而Na+离子浓度对吸附影响较弱;KMS-1与Th(IV)的离子交换反应在4 h时反应达到平衡,反应过程符合准二级动力学方程,Qe=180.51 mg·g-1,k=2.005×10-4g·mg-1·min-1;R2=0.9987;吸附等温线符合Langmuir等温模型,R2为0.9985;热力学数据分析得出:ΔHo=60.73 kJ·mol-1·K-1,ΔSo=19.02 J·mol-1·K-1和ΔGo<0,说明KMS-1吸附Th(IV)是一个放热且自发的过程,降低温度有利于KMS-1对Th(IV)的吸附。该离子交换反应最大吸附量为180.51 mg·g-1。K2xMnxSn3-xS6（KMS-1） was synthesized by hydrothermal method. The determination of structure and morphology was characterized by Scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and Fourier transform infrared spectrometer （FT- IR）. The result indicated that the KMS-1 had layered structure and good crystal structure. In addition, the ion-change of the layered K2xMnxSn3-xS6（ KMS-1 ） with Th（IV） was studied as a function of contact time, temperatures, Th（IV） initial concentration, pH value and Na ^＋ concentration under ambient conditions using batch technique. The resuhs indicated that the absorption of KMS-I with Th （IV） was strongly dependent on pH values, but weakly dependent on Na ＋ concentrate. Adsorption capacity increased with the increase of solution pH, and when the pH 〉 4, adsorption capacity no longer changed with pH; ion-change reaction of KMS-1 with Th （IV） reached equilibrium in 4 h and absorption of KMS-1 with Th（IV） was in accordance with pseudo second order kinetic model; the adsorption isotherm model used Freundlich model and Langmuir model. The adsorption isotherm was in accordance with Langmuir model, and Qe = 180.51 mg·g^-1 , k =2. 005 × 10^-4 g·mg^-1·min^-1 ; R2 =0. 9987. △H^0, △S^0 and AGO free energy were calculated from the experimental data： △H^0 = 60.73 kJ·mol^-1K^-1, △S^0 = 19.02 J·mol^-1·K^-1 and △G^0 〈 0. The results indicated that ion-exchange of KMS- 1 with Th （IV） was a spontaneous and thermopositive process, and the adsorption decreased with temperature increasing. The maximum -1 adsorption quantity was 180.51 mg·g^-1

关 键 词：层状硫化物K2xMnxSn3-xS6(KMS-1) Th(IV) 离子交换 

分 类 号：O647.32[理学—物理化学]