Larger hydrocarbons such as ethane and propane produce bilayer coatings. Chemical plants produce olefins by steam cracking of natural gas liquids like ethane and propane. The residual hydrogen, methane, ethane, and some propane is used as refinery fuel gas. Trace amounts of ammonia, acetylene, ethane, phosphine, and methane have also been detected. The reject gas from the system can contain carbon dioxide, nitrogen, methane, ethane, and hydrogen. Some minor products in the incomplete combustion of ethane include acetaldehyde, methane, methanol, and ethanol. These areas may be wetlands fed by subsurface ethane and methane springs. Another route to styrene involves the reaction of benzene and ethane. It also contains small amounts of ethane, propane, butane, some heavier alkanes, and nitrogen. Hexafluoroethane is a fluorocarbon counterpart to the hydrocarbon ethane. Some FCC gas recovery units may also separate out some of the ethane and ethylene. The C stream is split into ethylene and ethane. There are also traces of carbon, ethane, hydrogen sulfide, neon, oxygen, phosphine, and sulfur. They include ethane , acetylene , methylacetylene , diacetylene . The same concept is applied to organic compounds like ethane, butane etc.