催化光度法测定痕量钼——钼(Ⅵ)-盐酸联氨-酸性品红体系

Catalytic Spectrophotometric Determination of Trace Molybdenum With Molybdenum(Ⅵ)-Hydrazine Dihydrochloride-Fuchsine Acid System

基于钼(Ⅵ)催化盐酸联氨还原酸性品红反应,拟定了测定痕量钼的新催化光度法。可测定钼量范围为0.04～9.0μg/ml,检出限为4.6×10^(-3)μg/ml。用于测定豆类中钼。

A new catalytic spectrophotometric method for the determination of trace Mo has been developed. The method is based on the catalytic effect of Mo(Ⅵ) on the reduction of fuchsine acid with hydrazine dihy-drochloride. The effect of the solution pH,the reagent concentration and interfering ions on reaction rate has been studied. Under different temperature condition,the linear range of determination is 0. 04-9. 0μg/ml for molybdenum. The detection limit is 4. 6×103μg/ml,th|e relative standard deviation is 1. 2%. The apparent activation energy of catalytic reaction is 52. 7kJ/mol. The method has been used to determine trace molybdenum in bean samples.