AQUEOUS ABSORPTION OF NITRIC-OXIDE INDUCED BY SODIUM-CHLORITE OXIDATION IN THE PRESENCE OF SULFUR-DIOXIDE

The absorption of NO from a gas stream containing SO2 by aqueous solut ion of NaClO2 was studied in a bench scale scrubber. NOx removal of up to 95% was obtained using a packed bed scrubber. The corresponding SO 2 removals were 100%. Experiments tl;ere also conducted in a bubble co lumn and a spray chamber scrubber in order to obtain engineering data for scale-up and process design. A novel UV/photodiode array (PDA) met hod was developed for real-time monitoring of oxychlorine compounds in the scrubbing solutions. As a consequence of the data obtained with t he PDA system, a much better understanding of the chemistry of the scr ubbing system has led to a simpler mass transfer model than is availab le in the literature. Absorption rates are reported in terms of overal l reaction rates for a spray chamber scrubber and height of transfer u nit for a packed bed scrubber.