催化极谱法测定锑(Ⅲ)  

Catalytic Polarographic Determination of Stibium(Ⅲ)

作　　者：林洪[1] 崔云春[1] 白红梅[1] 陈文静[1] 

机构地区：[1]玉溪师范学院资源环境学院化学系,玉溪653100

出　　处：《理化检验（化学分册）》2013年第7期777-780,共4页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：云南省自然科学基金资助项目(2008CD215)

摘　　要：锑(Ⅲ)与铜铁试剂在0.20 mol·L^(-1)盐酸介质中,生成稳定的络合物,该络合物在溴酸钾存在下,于-0.38 V(vs.SCE)处产生一灵敏的极谱催化波,据此提出了催化极谱法测定痕量锑的方法。锑(Ⅲ)的浓度在4.8×10^(-1)~3.6×10^(-6)mol·L^(-1)范围内与峰电流的二阶导数呈线性关系,检出限(3S/N)为1.2×10^(-9)mol·L^(-1)。试验结果表明:该极谱波为吸附催化波,其电极过程为不可逆过程,电子转移数为3。方法用于水样中微量锑的测定,测定值与原子吸收光谱法测定结果相符。方法的回收率在94.2%~106%之间;测定值的相对标准偏差(n=6)在2.5%~3.2%之间。A stable complex between Sb（ Ⅲ ） with cupferron was formed in 0. 20 mol · L ^-1 HCl solution, and a sensitive catalytic polarographic wave of this complex was observed at the potential of --0. 38 V （vs. SCE） in the presence of KBrOa. Based on this fact, a method of catalytic polarography for the determination of Sb（ Ⅲ ） was proposed. Linear relationship between values of 2nd derivative of peak current and concentration of Sb（ Ⅲ ） was kept in the range of 4.8×10^-9 to 3. 6×10^-6 mol · L 1 with detection limit （3S/N） of 1.2 ×10^-9 mol · L^-1. It was found that the polarographic wave was an adsorption catalytic wave, its electrode process was an irreversible reduction process, and the number of electron transfer was 3. The proposed method was used in the determination of traces of antimony in water samples, giving results obtained in consistency with those obtained by AAS. Values of recovery and RSD＇s （n=6） found were in the ranges of 94.2%--106% and 2.5%--3.2% respectively.

关 键 词：催化极谱法 锑（Ⅲ） 铜铁试剂 溴酸钾 

分 类 号：O657.14[理学—分析化学]