INFLUENCE OF MIXED SULFUR NITROGEN-OXIDES ON THE REDOX KINETICS OF MANGANESE IONS IN AQUEOUS-SOLUTION

The influence of mixed sulfur-nitrogen oxides on the redox behaviour o f manganese(II,III) species in aqueous solution was studied kineticall y as a function of various concentrations and temperature. A series of oxides were found to reduce Mn(III) to Mn(II), whereby these oxides u ndergo a Mn(III)-induced hydrolysis reaction. The hydrolysis products were analysed by ion chromatography. These redox reactions can account for the inhibiting effect of the oxides on the metal-catalysed autoxi dation of sulfur(IV) oxides in flue gas desulfurization systems. Possi ble reaction mechanisms are suggested.