Potassium Persulfate by Electrolysis of Potassium Bisulfate

Potassium persulfate, the initiator that starts emulsion polymerisation (PVA glue), is made by electrolysing a cold, concentrated potassium bisulfate solution at about 1 A/dm² on a platinum anode with a graphite cathode. Sulfate is oxidised to persulfate at the anode, and the sparingly soluble salt crystallises out. It is a strong oxidant: keep it away from organic matter. The picture: our diagram of the cell.