Catalytic Spectrophotometric Determination of Osmium (Ⅳ) Using Osmium (Ⅳ)-KIO4-Chlorophosphonazo-mA System / 分析化学

ABSTRACT

A catalytic spectrophotometric method for the determination of micro amounts of osmium has been established based on the catalytic action of Os(Ⅳ) on the oxidation fading reaction of chlorophosphonazo-mA with KIO4 in alkaline-medium. The reaction conditions were optimized by orthogonal experimental design. The detection limit for osmium was 2.0 μg/L.Beer＇s law was obeyed in the range from 7.0 to 25.0 μg/L for Os(Ⅳ). The method has been applied to the determination of micro amounts of Os(Ⅳ) in concentrate of noble metals and secondary alloy,both of the relative errors were 0.9%. Recoveries varied from 95.38% to 106.0%.