Formation of Active Chlorine Oxidants in Saline-Oxone Aerosol

Abstract

The application of oxidative reactions of Oxone® [2KHSO5 KHSO4 K2SO4] as an active decontaminant has been mainly utilized through the aqueous solution. However, little is known about reactivity of aerosolized Oxone particles although the use of appropriate aerosolized oxidants would have significant value in remediating contaminated surfaces. In this study, the feasibility of producing active chlorine species from saline-Oxone aerosols was studied using a 2-m3 Teflon film chamber. To evaluate the oxidative capability of a saline-Oxone aerosol, the aerosol was collected onto filters impregnated with a dye (e.g., metanil yellow) that reacts with active chlorine in the aerosol, and monitored by UV-Visible spectroscopy. Spectral data showed that the dye compound was 86% oxidized by active chlorine within 4 min. There was no significant difference in oxidation capability between with buffer and without buffer system, although the presence of phosphate buffer somewhat retarded the formation rate of active chlorine in saline-Oxone aerosol particles. Saline-Oxone aerosols were found to be highly acidic as determined by UV-Vis spectroscopy, indicating that the aerosol produced mostly an undissociated form of active chlorine species (e.g., HOCl and Cl2) that was susceptible to partitioning into the gas phase. Our study concludes that the aerosolized saline-Oxone is a feasible chlorine oxidant, but the efficiency of such an approach still needs investigation.