Polarographic behavior of vanadium(V) in mixed mineral-acid-organic electrolytes

Reducing vanadium(V) in phosphoric-acid-potassium citrate-EDTA solutions in order to develop its polarographic determination in iron-containing materials was studied. Polarography with triangular potential sweep was used. The reference electrode was a saturated calomel electrode linked to the test via a potassium chloride salt bridge. Working solutions were prepared with phosphoric acid solution. It was established that polarographic characteristics depend on solution pH. Experimental currents of the second cathodic and anodic wave as functions of potential scan rate in order to examine the kinetics and mechanism of vanadium(V) reduction under optimum conditions was also studied and found to be irreversible. Polarographic characteristics are tabulated.