Nitrogen dioxide steel

Gaseous nitrogen dioxide is a brown, paramagnetic, non-flammable, toxic, strongly oxidizing, coiTosive substance shipped in approved, low-pressure steel cylinders. It is prepared in situ by heating lead nitrate ... 

Table I. Relative Rates of Nitrogen Dioxide Formation in the Steel Chamber...

Gaffney, J. S., Marley, N. A., and Steele, H. D., Aircraft measurements of nitrogen dioxide and peroxyacyl nitrates using luminol chemiluminescence with fast gas chromatography, Environ. Sci. Technol, 33, 3285-3289, 1999. 

In studies on sulfur dioxide, nitrogen dioxide, ozone, and other variables in specially designed environmental chambers, Haynie et al. (1978) found that only sulfur dioxide and humidity were statistically significant. Haynie later (1980) evaluated the corrosion of small specimens of galvanized steel and developed the following relationship ... 

When dry (0.1 percent moisture or less), nitrogen dioxide is not corrosive to mild steel at ordinary temperatures and pressures. Numerous metals and alloys such as carbon steel, stainless steel, aluminum, nickel, and Inconel are satisfactory for handling and storage. Under wet conditions, stainless steels resistant to about 60 percent nitric acid serve best. 

Equipment parts, such as valve stems, which are partly in contact with the atmosphere, should be stainless steel with sufficient chromium content to resist corrosion caused by leaks through stuffing boxes. Good quality ceramic bodies and Pyrex are satisfactory for handling wet or dry nitrogen dioxide. 

Nitrogen dioxide is also authorized for shipment in Specification 106A500X TMU containers and 105A500W tank cars, the latter of which are equipped with a combination pressure relief valve including a stainless steel or platinum frangible disk. Specification 110A500W tank cars are also authorized. See 49 CFR 173.336 [9]. 

The combustible components of the gas are carbon monoxide and hydrogen, but combustion (heat) value varies because of dilution with carbon dioxide and with nitrogen. The gas has a low flame temperature unless the combustion air is strongly preheated. Its use has been limited essentially to steel (qv) mills, where it is produced as a by-product of blast furnaces. A common choice of equipment for the smaller gas producers is the WeUman-Galusha unit because of its long history of successful operation (21). 

The polyesterification reaction is normally carried out in stainless steel vessels ranging from 8,000—20,000 L, heated and cooled through internal cods (Fig. 1). Blade agitators revolving at 70—200 rpm ate effective in stirring the low viscosity mobde reactants, which ate maintained under an inert atmosphere of nitrogen or carbon dioxide during the reaction at temperatures up to 240°C. 

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