(128f) Simultaneous Removal and Oxidation of NO and SO2 from Flue Gas by Combined Temperature and Fe2+ Activated Aqueous Persulfate Solutions

This work evaluates the simultaneous removal efficiency of NO (1000 ppm) and SO₂ (1550 ppm) from flue gas induced by the combined temperature and Fe²⁺ (0.01M) activation of aqueous persulfate (0.1M) and elucidates the chemistry and reaction pathways. The results indicated that both SO₂ in the flue gas and Fe²⁺ in solution improved NO removal. The conversion of NO (i.e., percent removal of inlet concentration) was 46.2% at 30°C and only slightly to 48.2% at 50°C; but sharply increased to 81.2% at 70°C, while SO₂ was completely removed at all temperatures. Also, a kinetic-mass transfer mathematical model utilizing the pseudo-steady state approximation technique for proposed comprehensive reaction pathways was developed. The model results, which appeared to fit the experimental results of the NO_x-S(IV)-S₂O₈^2--Fe²⁺ system remarkably well, was used to predict species and product concentrations, NO and SO₂ mass transfer coefficients, kinetic data and other process parameters.

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