Oxidation by Co3+ ions in aqueous acidic media

Meenakshi, A. ; Santappa, M. (1970) Oxidation by Co3+ ions in aqueous acidic media Journal of Catalysis, 19 (3). pp. 300-309. ISSN 0021-9517

Full text not available from this repository.

Official URL: http://www.sciencedirect.com/science/article/pii/0...

Related URL: http://dx.doi.org/10.1016/0021-9517(70)90251-4


Kinetics of oxidation of a wide variety of organic compounds by Co3+ in aqueous acidic media (H2SO4, HClO4, or HNO3) at constant [H+] and ionic strength, µ, in the temperature range, 5-25 °C have been investigated, the organic compounds chosen being hydroxy-compounds such as benzyl alcohol, allyl alcohol, ethylene glycol, propylene glycol, propane-1,3-diol, pinacol, glycerol, sorbitol, mannitol; ketones such as acetone, ethyl methyl ketone, n-propyl methyl ketone, isobutyl methyl ketone, cyclopentanone; acids such as malonic, glutaric, adipic, glycolic, diglycolic, citric, aceturic, crotonic, and itaconic acids; sugars such as glucose, fructose, sucrose; and ethers such as tetrahydrofuran and dioxane. All the reactions invariably obeyed second order kinetics, the order with respect to [CO3+] and [substrate] each being unity. Michaelis-Menten kinetics were observed only in glutaric acid oxidation. Inverse dependence on [H+] was observed in all the oxidations (except sucrose). Retardation of rate with [HSO4-] and effects of µ, added CO2+, and temperature were some other features studied. Relative rates of oxidation in the various acid media followed the sequence, H2SO4 < HNO3 < HClO4. Product analysis by VPC was carried out and the reaction stoichiometry for some oxidations, such as those of benzyl alcohol and pinacol, has been established. The rate laws have been derived and suitable reaction mechanisms were suggested. The second order rate constants (k2), acid-independent and acid-dependent rates (a and b), the corresponding rate constant ratio, kb/kaand the kinetic parameters, ΔE, ΔS, and A have been evaluated and discussed.

Item Type:Article
Source:Copyright of this article belongs to Elsevier Science.
ID Code:88464
Deposited On:28 Mar 2012 09:45
Last Modified:28 Mar 2012 09:45

Repository Staff Only: item control page