Formation of chlorinated species through reaction of SO₂ with NaClO₂ powder and their role in the oxidation of NO and Hg⁰.

This study examines gaseous chlorinated species generated from the reaction of sulfur dioxide (SO₂) with sodium chlorite powder (NaClO₂(s)) to obtain insight into the propensity of this process to enhance NO and Hg⁰ oxidation. A packed bed reactor containing NaClO₂(s) was used and the reaction temperature was set to 130 °C. Initially, we determined that the presence of SO₂ enhances the oxidation of NO and Hg⁰ by reaction with NaClO₂(s). We then introduced NO₂ into the gas mixture as a radical scavenger and determined that the chlorinated species generated by the reaction of SO₂ with NaClO₂(s) are OClO, Cl, ClO, and Cl₂. Based on these results, we suggest that such gaseous chlorinated ones are responsible for the enhancement of NO and Hg⁰ oxidation.