Acrylonitrile is a colorless, volatile organic compound with a pungent smell. The highly flammable liquid is manufactured by the reaction of ammonia, propylene, and air in the presence of a catalyst, which contains a complex of catalytic oxides comprising bismuth, potassium, chromium, cobalt, cesium, cerium, nickel, iron, and molybdenum. The yellow color of acrylonitrile indicates the presence of impurities, and it needs to be purified before being used in chemical manufacturing.