Ethylene autoignition temperature

Catalysts such as iron oxides cause isomeriza tion of the ethylene oxide to acetaldehyde with the evolution of heat. The acetaldehyde has a much lower autoignition temperature in air than does ethylene oxide, and the two effects may lead to hot-spot ignition (190,191). 

Group D gases, but hexane or gasoline, owing to their lower autoignition temperatures. For Group C tests, ethylene can be used for all test stages. 

The gases in the ethylene oxide reactor moved into the explosive region while being above the autoignition temperature. A violent explosion occurred, resulting in several injuries and significant plant damage. 

Ethylene An alkene (unsaturated aliphatic hydrocarbon) with two carbon atoms, CH2=CH2. A colorless, highly flammable gas with sweet odor (autoignition temperature, 543°C). Derived by thermal cracking of hydrocarbon gases or from synthesis gas. Used as monomer in polymer synthesis, refrigerant, and anesthetic. Also called Ethene. 

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