Modeling the synchronous absorption and oxidation of NO and SO2 by activated peroxydisulfate in a lab-scale bubble reactor

Sulfate-radical advanced oxidation technology is emerging for environmental remediation, and current research attention has been on applications to air pollution control. This study uses a physicochemical model to investigate and compare the kinetics of NO removal alone or synchronously with SO2 by heat-activated aqueous peroxydisulfate (or persulfate). The model allowed for the validations of experimental fractional conversion data for both NO and SO2 with remarkable agreements; and predictions of reaction species and nitrogen-sulfur product concentrations, new kinetic data, and lumped-kinetic rate constants with corresponding activation energies. The model also predicted increases in mass transfer coefficients (KLa) for NO with temperature (in the range 30-90 degrees C) in the absence of SO2. However, in the presence of SO2, KLa values for NO are significantly enhanced (especially at the lower temperatures) compared to the case for NO-only absorption and oxidation. The results should provide useful guidance to designing cost-effective single vessels for multicomponent flue gas treatments.

Automated summary

This study investigates the removal of nitrogen oxides (NO) and sulfur dioxide (SO2) using heat-activated peroxydisulfate in the presence or absence of SO2. The results show that the presence of SO2 significantly enhances the removal of NO. This research provides valuable guidance for designing efficient flue gas treatment systems.