A Novel Modification Method of Stainless-steel Electrode for Sulfur Preparation by Reduction of Sulfur Dioxide

A novel modification method of stainless-steel electrode for reduction of sulfur dioxide to prepare sulfur was reported. Sulfur dioxide can spontaneously react with modified stainless-steel electrode at a rate of 12.77 mA/cm2 to produce sulfur under acidic conditions without additional energy. Evidence was found for the destruction of passive film on the stainless-steel surface in the process of modification which leads to the open circuit potential of stainless-steel electrode shift negatively to the reduction potential range of sulfur dioxide. When modified stainless steel was used as cathode in electrolysis, the contributions of impressed current and redox reaction made the sulfur yield up to 88% within 3 hours.