What is the gas that can be obtained from separating crude oil?

The gas obtained from separating crude oil is primarily natural gas, which mainly consists of methane. During the refining process, lighter hydrocarbons are separated and can include ethane, propane, and butane, which are also gases at room temperature. These gases are valuable as energy sources and feedstocks for the petrochemical industry. Additionally, small amounts of hydrogen sulfide and other volatile organic compounds may also be present.