Patent ID: 8236161

Claim:
An apparatus for electrolyzing sulfuric acid, comprising: an electrolytic cell comprising a cathode chamber having a cathode and an anode chamber having an anode, the cathode chamber and the anode chamber being separated by a diaphragm; a sulfuric acid tank configured to store the sulfuric acid; a supply pipe connecting the sulfuric acid tank to an inlet port of the cathode chamber; a connection pipe connecting an outlet port of the cathode chamber to the inlet port of the anode chamber; a first supply pump provided on the supply pipe and configured to supply the sulfuric acid from the sulfuric acid tank to the cathode chamber through the supply pipe; a drain pipe connected to an outlet port of the anode chamber and configured to supply to a solution tank a process solution containing an oxidizing agent generated by electrolysis in the anode chamber; measuring means for measuring at least one of electrical conductivity, an amount of the oxidizing agent and a concentration of the sulfuric acid of the process solution generated by electrolysis, flowing in the drain pipe and containing the oxidizing agent; and control means for maintaining the amount of the sulfuric acid supplied by the first supply pump to maintain the process solution generated by electrolysis in the anode chamber constant in terms of properties, in accordance with the results of the measuring performed by the measuring means; wherein the process solution stored in the solution tank is supplied to a process unit through a second supply pipe on which a second supply pump is provided and is supplied back to the solution tank through a first return pipe when the process solution is not used in the process unit, and heating means is provided on the first return pipe to control the temperature of the process solution being supplied back to the solution tank.