Study on the catalytic effects of ruthenium on the oxidation of basic dyesby KIO4 and its analytical applications

Three sensitive catalytic spectrophotometric methods have been developed fo r the determination of ruthenium(III), based on its catalytic effects on th e oxidation reactions of three basic dyes: nile blue (NB), butyl rhodamine B (BRB) and methylene blue (MB), by KIO4 in acidic medium at 90+/-0.5 degre es C. The above reactions are followed spectrophotometrically by measuring the decrease in the absorbance at 630 nm, 555 nm and 670 nm for the catalyt ic reactions of NB, BRB and MB, respectively. The working curves for the th ree recommended reaction-rate methods are linear in the concentration range over 0.0080-1.2 and 0.0080-0.72 mu g/L for NE and BRB methods, and 0.0-1.2 and 1.2-5.6 mu g/L for MB method. Almost no foreign ion interfered in the determination at less than 10-fold concentration of Ru(III), The methods ar e highly sensitive, more selective and very stable, and have been successfu lly applied for the determination of trace amount of ruthenium in some ore and metallurgy products. The kinetic parameters and the catalytic reaction mechanism have also been studied.