Natural Gas Condensate is a natural gas by-product. Hydrocarbons are dissolved in natural gas at high pressure. When the gas expands during production, where pressure is reduced to near-atmospheric levels, some of the hydrocarbons condensate out of the gas as a liquid. The liquid condensate is collected and transported to an oil refinery.

Condensate has a typical composition of:

• C2 as Ethane - 0-5% by weight
• C3 as Propane - 0-15% by weight
• C4 as Butane - 0-45% by weight
• C5 as Pentane - 5-70% by weight
• C6 as n-Hexane and Cyclohexane - 25-95% by weight
• C7 as heptane - 25-95% by weight
• C8 as Octane - 25-95% by weight

Acid gas may also contain up to 20% hydrogen sulfide contaminant by weight and the aromatic hydrocarbons benzene, toluene, mixed xylenes and ethylbenzene. Natural gas may also contain mercury, which is also removed from the gas and collected.