Notes on the Preparation and Analysis of Ruthenium(III) and Ruthenium(IV) in Sulfate Medium
Technical note no. 1
ROYAL INST OF TECH STOCKHOLM (SWEDEN) DEPT OF INORGANIC CHEMISTRY
Pagination or Media Count:
For equilibrium studies, pure solutions of rutheniumIII and rutheniumIV perchlorates or sulfates are needed. A survey is given of synthetic and analytical methods reported in literature. Since none of them was suitable for our purpose, new or modified methods were worked out. For the preparation of rutheniumIV sulfate solution, RuO4 was reduced with H2O2 in dilute H2SO4 and the rutheniumIV cations separated from complex anions by a cation exchanger. For the preparation of rutheniumIII, RuO4 was reduced with SO2, the excess SO2 removed and the sulfite complex decompressed. Total ruthenium was determined by reducing to metallic ruthenium, using Mg metal, and then weighing. For determining rutheniumIII or rutheniumIV, a redox titration method is proposed a known excess of ceriumIV sulfate in 2 M H2SO4 is added, the RuO4 formed is boiled off and the remaining ceriumIV backtitrated with ironII ferroin. For the determination of H, the total analytical concentration of H, in purely cationic RuIV solutions, the ruthenium may be either held back in a H -saturated ion exchanger or bound by adding acetylacetone. The H set free can be in both cases be titrated with standard NaOH. Concordant results were obtained using these two methods.
- Inorganic Chemistry