Removal of Nitrogen-Containing Gases

Of equal interest is the occurrence of nitrogen compounds in gases produced by coal combustion. These compounds, the oxides, originate from the organically bound nitrogen in the coal  

NOx are formed during burning by oxidation, at the high temperatures, of the nitrogen in the fnel and in the air. This has given rise to the terminology thermal and fuel as a means of distinguishing between the two sources of NOx. But, be that as it may, NOx from whatever the sources are pollutants that must be removed from gas streams. 

Vanadium oxide/aluminum oxide and iron/chromium, as well as the systems based on iron oxide itself, have also been reported to be successful for the removal of NOx from gas streams. 

Nitrogen compounds must be absorbed in several chemical and related processes, the most important of which is the absorption of nitrogen peroxide in water for the manufacture of nitric acid. Absorption of nitrous gases also takes place in the lead-chamber process used for the production of sulfuric acid, in the metallurgical industries where metals are treated with nitric acid, and in the purification of several tail gases. 

Argonne. 1990. Environmental Consequences of, and Control Processes for. Energy Technologies. Argonne National Laboratory. Pollution Technology Review No. 181. Noyes Data Corporation, Park Ridge, NJ, Chapter 11. Benson, H.E. 1981. In Chemistry of Coal Utilization, Second Snpplementary Volume, M.A. Elliott (Ed.). John Wiley Sons, Inc., New York, Chapter 25. 

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