Thermal decomposition behavior of casting raw materials under different atmospheres and temperatures.

To determine the volatile organic compounds (VOCs) generated by casting resin sand and its binder during the casting process, this paper studied the process of resin pyrolysis and the different types of VOCs generated under different atmospheric conditions, as well as the temperature range of which the main pollutants are produced. Results indicate that resin pyrolysis can affect the types and characteristics of products under different atmospheric conditions. Oxygen in the air can accelerate the decomposition or combustion of organic matter in the sample. Under anaerobic conditions, the main products are benzene and ester products, primarily including dimethyl succinate and 1,2,3,5-tetramethylbenzene, in temperature range of 200-600 ℃. Under oxygen-containing conditions, the main products are ethers, benzene, and hydrocarbons, specifically ethylene oxide and 2-methylbutane, produced at temperatures above 200 ℃. This study provides theoretical guidance for the optimization design and environmental protection of molding sand and its binders in the casting industry, and provides technical support for the industrial application and development of molding sand.