硫氰酸汞间接分光光度法测定三乙基铝中氯的含量

建立了测定三乙基铝中氯含量的硫氰酸汞间接分光光度法。在酸性溶液中,硫氰酸汞与氯离子反应后游离出硫氰酸根离子,硫氰酸根离子与铁离子反应生成红色硫氰酸铁络合物,于460 nm波长处测定该络合物的吸光度,从而间接获得氯的含量。对测量过程的波长、酸度、显色剂的用量、显色剂的稳定性等因素进行了探讨。氯的质量在0~50μg范围内与吸光度呈良好的线性关系,线性相关系数r=1.000 0,测定结果的相对标准偏差为0.07%~0.20%(n=6),加标回收率为94.8%~105.0%。该法适用于三乙基铝工业品中氯含量的测定。

Indirect Determination of Chloride in Triethylaluminium by Mercuric Thiocyanate Spectrophotometry

Indirect determination of choloride in triethylaluminium by mercuric thiocyanate spectophotometry was set up. In acidic solution,mercuric thiocyanate reacted with chloride ion and generated SCN-, and SCN-reacted with iron (Fe3+)to generate red iron complex thiocyanate, whose absorbance peak was determined at 460 nm, and chlorine content was measured indirectly. Process of measuring wavelength, acidity, the amount and stability of chromogenic agent were discussed. The concentration of chlorine was linear with the absorbancy in the range of 0-50 μg with the correlation coefficient of 1.0000, and the relative standard deviation of the results were 0.07%-0.20%(n=6), and the recoveries were 94.8%-105.0%. This method was suitable for determination of chloride content in triethylaluminium.