Ammonium chloride, corrosive effect

This study resulted in a series of reports on a comprehensive evaluation of fire-retardant treatments for wood (2-6). One hundred and thirty single chemicals or combinations of chemicals in the form of various salts were evaluated for flame-spread reduction, smoke, and corrosivity. Diammonium phosphate ranked first in reducing flame spread, followed by monoammonium phosphate, ammonium chloride, ammonium sulfate, borax, and zinc chloride. Zinc chloride, although excellent as a flame retardant, promoted smoke and glowing. Ammonium sulfate was the least expensive, but under certain environmental conditions it was corrosive to metals. None of the 130 compositions tested was considered ideal because of the adverse effects on some of the properties of wood. Several reviews of the subject are available and provide additional background material (J, 7-JO). 

EGMBE can be added to add however, it may be most effective as an additive to the overflush (ammonium chloride solution). Mutual solvent will strip adsorbed additives, such as the corrosion inhibitor, from formation... 

Aluminium is very widely used in equipment for the transportation and the storage of ammonia water, and in production plants for nitric acid. As in gaseous ammonia, the presence of carbon dioxide CO2, sulphur dioxide SO2, hydrogen sulphide H2S, ammonium carbonate NH4CO3 and ammonium sulphide S(NH4)2 in ammonia does not alter the corrosion resistance of aluminium. On the other hand, the presence of chlorides (and of salts of certain heavy metals such as copper) has a noxious effect. 

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