Study on the removal of NO(x) from simulated flue gas using acidic NaClO2 solution.

The study on the removal of NO(x) from simulated flue gas has been carried out in a lab-scale bubbling reactor using acidic solutions of sodium chlorite. Experiments were performed at various pH values and inlet NO concentrations in the absence or presence of SO2 gas at 45 degrees C. The effect of SO2 on NO oxidation and NO2 absorption was critically examined. The oxidative ability of sodium chlorite was investigated at different pH values and it was found to be a better oxidant at a pH less than 4. In acidic medium, sodium chlorite decomposed into ClO2 gas, which is believed to participate in NO oxidation as well as in NO2 absorption. A plausible NO(x) removal mechanism using acidic sodium chlorite solution has been postulated. A maximum NO(x) removal efficiency of about 81% has been achieved.