Nitrogen-containing compounds in foundry mold emissions

Nitrogen compounds have been identified in the decomposition products from several commonly used foundry sand binders. These compounds include nitrogen oxides, hydrogen cyanide, ammonia, simple aromatic amines, and isocyanates. The concentrations of these compounds in foundry mold emissions do not appear to be directly related to the nitrogen content of the organic binders. Measurable concentrations were observed in some cases, indicating the necessity for periodic, monitoring in the foundry. Adequate ventilation will permit the use of these binders. The substitution of nitrogen-free binders suggests another possible control strategy.