Induced reactions involving intermediates produced by partial oxidation of thiocyanate

5 INDUCED REACTIONS INVOLVING INTERMEDIATES PRODUCED BY PARTIAL OXIDATION OF THIOCYANATE 

Recently an interesting observation was described by Pungor et They 

These and similar results can be explained if the simultaneous reduction of hydrogen peroxide is due to an induced reaction. To show the characteristic features of this reaction some results are presented in Table 19 and Table 20. The procedure for these measurements was as follows. The solution of peroxy compounds given in columns 1 and 2 was made up to 20 ml and the pH was adjusted to the given value. Then potassium thiocyanate solution was added and, after the reaction time noted, the process was quenched by adding potassium iodide solution (0.3 g KI). After 5 sec the solution was acidified with 1 ml 2 iV sulphuric acid then using, molybdate catalyst solution, the iodine liberated was titrated with standard thiosulphate. 

The data in Tables 19 and 20 show that both peroxysulphuric and peroxyacetic acid give the induced reduction of hydrogen peroxide by thiocyanate. The induced reduction depends strongly on the pH of the solution and on the concentration of thiocyanate. At pH 3 both peroxy acids reacts more slowly 

DEPENDENCE OF INDUCED REDUCTION OF HYDROGEN PEROXIDE ON EXPERIMENTAL CONDITIONS IN THE H2O2-H2SO5-SCN SYSTEM 

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