The oxidation of thiocyanate ion by hydrogen peroxide. I. The pH-independent reaction

The products of the reaction between hydrogen peroxide and thiocyanate ion in the range 4 < pH <12 are sulfate, cyanate, ammonia and carbonate. The reaction is first order in each of the reactants and independent of the hydrogen ion concentration within the specified range. The rate constant in acetate buffer at ionic strength 0.27 is given by the expression k = 4.0 X 10(9) exp (- 15,500/RT) l. mole(-1) min.(-1) within the temperature range 20-50 degrees. The rate-determining step appears to be direct electrophilic reaction of molecular hydrogen peroxide with thiocyanate ion.