Product identification and kinetic data for the reaction of S(IV) with N(III) oxoacids in aqueous solution in the absence and presence of metal ions
Abstract The reaction of S(IV) with N(III) oxoacids was studied in the pH range 3.5–5.2, and in the absence and presence of metal ions, using ion-pair chromatography (IPC), and stopped-flow and conventional spectroscopy. Product identification and distribution of the sulphur-nitrogen oxides formed during this reaction was determined by IPC. The empirical rate law suggests that HONO and HSO − 3 are the main reactive species in the investigated pH range, and the data are compared to that available from the literature. Hydroxylaminedisulphonate was found to be the only identifiable sulphur-nitrogen oxoanion produced during the reaction. The effect of Mn(II/III) and Fe(II/III) on the reaction was studied and a meaningful catalytic effect was found for Fe(II). This is ascribed to the interaction of Fe(II) with HONO to produce a nitrosyl complex that can react with HSO − 3 according to the Boedeker reaction.