APPLICATION OF PHOTOLYSIS AND ADSORPTION PRECONCENTRATION TO THE SPECTROPHOTOMETRIC DETERMINATION OF RUTHENIUM AND OSMIUM IN SOLUTIONS OF CARBONYL-COMPLEXES

The behavior of carbonyl complexes of ruthenium and osmium in chloride solutions under exposure to UV light was studied by electronic absorp tion spectra and electron paramagnetic resonance. It was found that, u nder exposure to UV light, the M-CO bond (M = Ru, Os) breaks according to the reaction described previously for nitroso complexes. On the ba sis of electronic absorption spectra measured in solutions of complexe s during exposure to UV light, it was revealed that the quantum yield of photoreaction products in hydrochloric acid solutions decreases in the following order: [RuCOCl5](2-) > [RuNOCl5](2-) > [OsCOCl5](2-). A procedure for the spectrophotometric determination of ruthenium and os mium complexes with multiply bonded ligands using exposure to UV light is developed. The adsorption of carbonyl and nitroso complexes of rut henium and osmium by various adsorbents was studied as a function of t he temperature and the concentration of HCl. It was found that the ads orption proceeds according to the anion-exchange mechanism. Conditions for preconcentration of nitroso and carbonyl complexes of ruthenium a nd osmium by the POLIORGS-IV-N adsorbent were chosen. Conditions for q uantitative desorption of [RuCOCl5](2-) with thiourea used as an eluan t were determined. A procedure for the adsorption-spectrophotometric d etermination of carbonyl complexes of ruthenium using exposure to UV l ight with the detection limit of ruthenium as low as 0.02 mu g/mL and an analytical range from 0.02 to 0.45 mu g/mL is developed.