Study on the Catalytic Effects of Ruthenium on the Oxidation of Basic Dyes by Kio4 and its Analytical Applications

ABSTRACT Three sensitive catalytic spectrophotometric methods have been developed for the determination of ruthenium(III), based on its catalytic effects on the 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 °C. The above reactions are followed spectrophotometrically by measuring the decrease in the absorbance at 630 nm, 555 nm and 670 nm for the catalytic reactions of NB, BRB and MB, respectively. The working curves for the three recommended reaction-rate methods are linear in the concentration range over 0.0080-1.2 and 0.0080-0.72 μg/L for NB and BRB methods, and 0.0-1.2 and 1.2-5.6 μg/L for MB method. Almost no foreign ion interfered in the determination at less than 10-fold concentration of Ru(III). The methods are highly sensitive, more selective and very stable, and have been successfully 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.