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 °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.