Investigation of the oxidation of cerium by ozone in nitric acid solutions. [Ce(III). -->. Ce(IV)]
The oxidation of Ce(III) to Ce(IV) by ozone was investigated in 8.9 M HNO/sub 3/ in the interval of Ce concentrations from 5 x 10/sup -2/ to 1 x 10/sup -5/ M. It was shown that at room temperature complete and stable oxidation occurs only at concentrations of Ce greater than or equal to 5 x 10/sup -2/ M; at concentrations of Ce less than 1 x 10/sup -5/ M practically no oxidation is observed. When solutions of ozonized Ce are allowed to stand, a reduction of Ce(IV) occurs. The rate of reduction corresponds to a first-order reaction relative to Ce(IV). The value of the apparent rate constant of the reaction increases monotonically with decreasing Ce concentration. At a constant concentration of Ce, the value of the constant is higher, the lower the concentration of nitric acid and the higher the concentration of residual ozone and its decomposition products. In the light the reduction of Ce(IV) occurs substantially more rapidly than in darkness.
- OSTI ID:
- 7361598
- Journal Information:
- Sov. Radiochem. (Engl. Transl.); (United States), Vol. 17:2; Other Information: Translated from Radiokhimiya; 17: No. 2, 206-210(1975)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CERIUM COMPOUNDS
OXIDATION
OZONE
CHEMICAL REACTIONS
AQUEOUS SOLUTIONS
CHEMICAL REACTION KINETICS
NITRIC ACID
REDUCTION
DISPERSIONS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
KINETICS
MIXTURES
RARE EARTH COMPOUNDS
REACTION KINETICS
SOLUTIONS
400201* - Chemical & Physicochemical Properties