Kinetics and mechanism of oxidation of α-propylene glycol by dihydroxydiperiodatonickelate(IV) in alkaline medium

The kinetics of oxidation of alpha-propylene glycol (alpha-PG) by dihydroxydiperiodatonickelate (IV) (DPN) in alkaline medium was studied with spectrophotometry in a temperature range of 293.2 similar to 308.2K. The reaction was found to be pseudo-first order with respect to DPN and fractional order to alpha-PG. The rate increases with the increase in [OH-] and decreases with the increase in [IO4-]. Added salts did not affect the rate and no free radical, was detected. A mechanism of reaction involving a pre-equilibrium of an adduct formation between alpha-PG and dihydroxymonoperiodatonickelate (IV) (MPN) is proposed, which can explain all the experimental results. The activation parameters of the rate-determining step have been calculated.