Sulphuric acid prodn. by anodic oxidn. of sulphur dioxide - in the presence of water and hydrogen iodide

摘要

The process comprises the anodic oxidn. of SO2 in water contg H iodide in the anode compartment of an electrolysis cell which is sepd. from the cathode compartment by a diaphragm permeable to H ions. Pref. excess gas. SO2 is fed into the anode compartment. The concn. of the sulphuric acid in the anolyte is 35%. The presence of iodine eliminates excessive voltage and the prodn. can be carried out at 0.25-0. 3V.