Quantitative study of the formation of inorganic chemical species following corona discharge. II. Effect of SO2 traces on the production of HNO2 and HNO3 in a humid atmosphere

The effect of sulfur dioxide traces on the formation of nitrous and nitric acid resulting from exposure to corona discharge in a composition-controlled, humid atmosphere was investigated. The production of NO2− and NO3− at the trace level was found to increase linearly with the corona discharge time, electric current intensity and quantity of electricity, but it was significantly lower in the presence of SO2 traces. This decrease is attributed to the oxidation of SO2 into sulfuric acid by OH radicals produced by corona discharge. The formation of S042− ions depends on the quantity of electricity and the amount of SO2 introduced in the atmosphere, while the formation of HSO3− ions is a function of the electric wind and diffusion at air-water interface.