The State of Ruthenium in Nitrite–Nitrate Nitric Acid Solutions as Probed by NMR
Russian Journal of Inorganic Chemistry
, E-ISSN: 1531-8613
Nikolaev Institute of Inorganic Chemistry SB RAS
Boreskov Institute of Catalysis SB RAS
International Science and Technology Center
The state of ruthenium in nitric acid solutions treated with sodium nitrite has been studied by 14N, 15N, 17O, and 99Ru NMR. In the acidity range 2.7-0.12 mol/L, the dominating ruthenium species are the [RuNO(NO2)2(NO3)(H2O)2]0 and [RuNO(NO2)2(H2O)3]+ complexes. When the acidity is decreased to 0.06 mol/L, trinitro-and tetranitronitrosoruthenium(II) complexes predominate in solution. In an acidic medium, the trinitro-and tetranitronitrosoruthenium(II) complexes exhibit catalytic activity toward oxidation with air of nitrite to nitrate.