Kinetics and mechanism of oxidation of l-ascorbic acid by peroxomonosulphate in acid perchlorate medium. Role of copper (II) as a trace metal-ion catalyst

The kinetics of oxidation of l-ascorbic acid by peroxomonosulphate (PMS) in presence and absence of Cu(II) catalyst has been studied. The stoichiometry of the reaction is represented by the following:H2A + HSO5− → A + HSO4− + H2OThe order with respect to ascorbic acid and peroxomonosulphate is one each. The rate following law in presence of Cu(II) as catalyst has been suggested:k2''−kun'=k1''K1'+K1k2''K2'H+CuII