Abstract
The cationic surfactant, cetylpyridinium chloride (CPC) inhibits the CrVI oxidation of formic acid in a monotonic fashion in aqueous H2SO4 media. On the other hand, under comparable conditions, CPC catalyses the CrVI oxidation of oxalic acid and then it inhibits the reaction after attaining a maximum value in the rate vs [CPC]T profile. The observed micellar effect has been explained in the light of the proposed reaction mechanism and it provides an indirect evidence in favour of 3e-transfer step for CrVI oxidation of oxalic acid.
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