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Show ( - y. Table 5. N02 Effect on NO Absorption in 0.5 M NaOH Conc. ppm 300 500 800 NO(in) ppm 379 600 826 NO(out} ppm 17 17 10 Abs ~o N02 (in} ppm 95.6 336 97.3 595 98.8 833 N02 (out} ppm o o o Abs ~o 100 100 100 OXYGEN EFFECT ON NO ABSORPTION IN CAUSTIC AQUEOUS SCRUBBING Oxygen is present in incinerator gaseous effluent because excess air is used to make sure incinerator feed is completely combusted. Since oxygen react with NO to form N0 2 , it is important to determine its contribution to NO absorption. The following runs were performed to test this effect. Gas: 300, 500, 800, or 2000 ppm NO; 5% O2 ; and Balance N2 Scrubbing Solutions: 0.0001, 0.01, or 1 M NaOH Results in Table 6 indicate that no significant change in NO absorption. in caustic aqueous scrubbing occurs due to introduction of 5% O2 into the flue gas mixture. Table 6. Effect of 5% Oxygen on NO Absorption in caustic Aqueous Scrubbing· NO (ppm) 300 500 800 2000 Absorption % Conc. of NaOH (molarity) 0.0001 0.01 1.00 1.0 0.4 0.5 1.1 0.7 0.7 0.4 0.9 1.0 0.6 0.6 · 2.4 OXIDATION OF NO BY NaCI02 IN AQUEOUS. SCRUBBING A number of experiments were performed to evaluate the potential of sodium chlorite (NaCl02 ) to oxidize NO in aqueous scrubbing under the following conditions Gas: 2000 ppm NO in N2 Scrubbing Solution: 0.008 M, NaCl02 , 1.3*10-4 M, Na2So4 and 8 |