催化动力学分光光度法测定铬

研究了催化动力学分光光度法测定痕量铬。在硫酸溶液中,研究了痕量铬(Ⅵ)对溴酸钾氧化橙黄Ⅳ退色反应的催化效应及其动力学条件,建立了测定痕量铬(Ⅵ)的新方法。结果表明,最佳条件为:50 mmol/L硫酸溶液用量为3.0 mL,0.01%橙黄Ⅳ溶液用量为3.0 mL,5 mmol/L溴酸钾溶液用量为1.5 mL,在50℃水浴下反应6 m in,加入抗坏血酸溶液终止反应,并进行了干扰分析,方法的线性范围为0.2~1.0μg/L,检出限为1.09×10-6μg/L。该法用于水中痕量铬(Ⅵ)的测定,结果满意。

Catalytic kinetic spectrophotometric method for the determination of chromium

A new catalytic kinetic spectrophotometric method for the determination of traces of chromium was studied.It was based on the fact that oxidation of orange Ⅳ by potassium bromate was catalyzed by chromium in sulfuric acid,a new catalytic kinetic spectrophotometric analysis method for the determination of traces of chromium has been planted.The optimum experimental conditions are determined,the amount of sulfuric acid(50 mmol/L) is 3.0 mL,the amount of potassium bromate(5 mmol/L) is 1.5 mL,the amount of orange Ⅳ(0.01%) is 3.0 mL,the reaction time is 6 min at 50 ℃,at last,Vc is added to stop reaction,and analysis interference test is made.The linear range is 0.2～1.0 μg/L and the detection limit is 1.09×10-6 μg/L.The procedure has been used to determine the content chromium in water with satisfactory results.