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Show ABSORPTION OF NOX INDUCED BY SODIUM CHLORITE OXIDATION ?~ Henry Shaw and Chen-Lu Yang - Department of Chemical Engineering, Chemistry & Environmental Science New Jersey Institute of. Technology Newark, New Jersey 07102 ABSTRACT Complete absorption of NO was achieved in aqueous solutions of alkaline NACl02 at room temperature and atmospheric pressure. Experiments were conducted by bubbling various mixtures of NO, NO and 02' with the balance N2 into a liter of scrubbing sofution. A greenish yellow color in the solution was observed after three minutes of operations. It is assumed that the color represented an intermediate, probably Cl02 , active in the oxidation of NO. The mole ratio of the total amount of NO that flowed through the reactor to NaCl02 in the initial solution is 0.95 at breakthrough. The material balance, determined using ion chromatography showed that only anions in solution were N0 3 - and Cl-. It should be noted that the pH of the scrubbing solution decreased rapidly from 10 to 12 to about 2. Consequently, the actual scrubbing was accomplished under acid conditions. Low concentrations of NaOH helped absorb NO, while high concentrations of NaOH inhibited the absorption. This is probably due to neutralization of the acid needed to promote the oxidation of NO with NaClO. Current research is directed at determining the mass transfer coefficient as well as the effects of temperature and other flue gas components on the No absorption. INTRODUCTION Nitrogen oxides (NOx ) are mixtures of compounds of nitrogen and oxygen, namely, N20, NO, N20 3 , N0 2 , N204 and N20 5 generally found in effluents from combustion sources. The predominant NOx compounds are NO and N0 2 . They are formed as a result of the reactions of atmospheric nitrogen with atmospheric oxygen at high temperatures. Also, large quantitative of NOx are formed from the oxidation of nitrogen compound found in fuel or in wastes being incinerated. More than 90% of NO emitted from stationary combustion sources consist of NO whic~ is relatively insoluble in inorganic aqueous solutions. Finding a way to control NO is essential for the prevention of air pollution and acid rain. Nitrogen oxides are emitted as nitric oxide (NO) from a variety of industrial sources. The estimated emissions of NOx have large uncertainties associated with them. About 70-90% ot atmospheric NOx emission are from anthropogenic sources. There are three major natural sources of NOx . The largest is 1 |