混合表面活性剂对铊(Ⅰ)的示波极谱电流的增敏效应  

Enhancement of Oscillopolarographic Current of Thallium (Ⅰ)by Mixed Surfactant

作　　者：张月霞[1] 刘杰民 朱腾[2] 

机构地区：[1]冶金部钢铁研究总院,北京100081 [2]北京科技大学,北京100083

出　　处：《分析化学》1996年第12期1391-1395,共5页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金;中科院长春应用化学研究所电分析化学开放研究实验室资助

摘　　要：在盐酸-柠檬酸钠缓冲溶液（pH3．7）中，铊（Ⅰ）于-0．52V（vs．SCE）处的小电流被碘化钾增敏，再加入十二烷基苯磺酸钠和TritonX－200，该电流共增敏110倍，同时电流峰形改善，对称性好；铊（Ⅰ）浓度在4μg／L～0．5mg／L范围内和电流峰高呈线性；相关系数（r）为0.9998;检出限为5X10－9mol／L。文中较详细研究了增敏机理、电流特性、电极过程的可逆性及反应机理。结果表明该体系服从Frumkin吸附等温式。计算了吸附系数（β）、吸引因素（v）、吸附自由能（△G°）等。方法已用于合金试样分析。In the hydrochloric acid-sodium citrate buffer solution(pH 3. 7) the small current of thallium(Ⅰ ) at -0. 52 V(vs. SCE) was increased by KI. After adding sodium dodecylbenzene sulfonate (SDBS) and Triton X-200, this current could be enhanced totally about 110-fold as compared with the original, meanwhile the shape and the symmetry of the current peak were improved. A linear relationship between current peak height and concentration of thallium(Ⅰ ) holds within 4μg/L^0. 5 mg/L T1(Ⅰ ). The correlation coefficient(r)and detection limit are 0. 9998 and 5 X 10-9 mol/L respectively. The enhancement mechanism, current character, reversibility and reaction mechanism of electrode process were studied in detail as well. Results demonstrated that the system enhanced by KI and mixed suffactant(SDBS+Triton X-200) obeys Frumkin adsorption isotherm formula. The adsorption coeffcient (β), attraction factor (v) and ddsorption free energy (△G°), etc., were calculated.The proposed method has been applied to the analysis of alloy samples.

关 键 词：铊 示波极谱法 表面活性剂 高温合金 增敏效应 

分 类 号：O614.373[理学—无机化学] TG132.32[理学—化学]