Intensification of NO(x) Conversion over Activated Coke by Ozone Oxidation for Sintering Flue Gas at Low Temperatures

[Image: see text] Denitration (De-NO(x)) over activated cokes (ACs) for sintering flue gas needs intensification. Gaseous reactions in a gas mixture containing NO, NO(2), and NH(3), with the effect of O(2) concentration and moisture, were taken into consideration in the study of NO(x) conversion over ACs. Experimental studies on NO(x) conversion with and without NH(3) over ACs were conducted using a fixed-bed reactor at 100 °C. The results demonstrated that moisture significantly affected NO(x) removal over ACs, especially the NO(2) conversion. Under dry conditions, a disproportionation reaction of NO(2) over ACs dominated NO(x) conversion with no NH(3), whereas apparent fast selective catalytic reduction (SCR) over the ACs was observed in the presence of NH(3). Regardless of the presence of absence of NH(3) in wet mixtures, NO(2) adsorption on ACs via the disproportionation route dominated the NO(x) conversion. Increasing the NO(2)/NO ratio in the simulated flue gas enhanced the NO(x) conversion rate over ACs. −C(ONO(2)) deposition on ACs generated by the disproportionation route inhibited NO(x) conversion with time. O(3) oxidation was found to be efficient in increasing the NO(2)/NO ratio and intensifying the NO(x) conversion compared with commercially direct NH(3)-SCR over ACs. Increasing the temperature and decreasing the gas hourly space velocity can promote NO(x) conversion over ACs after O(3) oxidation. NO oxidized with O(3) coupled with NH(3) spray and continuous regeneration of ACs is a potential method for removing NO(x) from sintering flue gas.