Sometimes customers need to analyze natural gas and petroleum products, whether it is to confirm the purity of the product by looking for the impurities which may be present, or for an environmental reason such as a spill or leak. In order to choose the correct GC column and reference standards, one needs to know the hydrocarbon ranges of these products.
Since many of these products are analyzed following ASTM International methods to determine their purity and to confirm that they meet certain specifications, I highly suggest you review the information contained within this link that was created by the petroleum experts at Restek. It will guide you to an appropriate ASTM method, GC column(s) and reference standard(s).
If the analysis is for environmental reasons and not product quality, the links below should help guide you on a variety of topics. Although I included primarily US EPA methods, I also included a few state specific methods.
For information on underground storage tanks, you may wish to review the links below.
For environmental analytical methods, including contamination via spills and leaks, you may wish to consider EPA 8015/8260/8270.
If you are looking to achieve a more specific and/or comprehensive analysis, consider one of these state methods shown below.
Please remember that, as natural products generally produced by either natural gas processing or by the distillation of crude oil, these ranges can vary, which is why I stated that they are average (approximate). I also included their average/approximate boiling point range (where applicable) and links showing Restek chromatograms & reference standards and/or information (mostly from Wikipedia) on the product. I hope you find this information useful for your next natural gas or petroleum product analysis.
Raw Gas: Primarily C1 (methane), lesser amounts of C2 hydrocarbons through C4 hydrocarbons + impurities such as light sulfur gases, fixed gases and moisture.
Other condensates may also be included (C5+).
Processed Natural Gas/Liquefied Natural Gas (LNG): Primarily C1 (methane), low levels of C2 (ethane) and very low levels of impurities.
LPG (Liquified Petroleum Gas)
Primarily propane (C3) and butane (C4) with low levels of other light hydrocarbon gases.
Average hydrocarbon range of C6 through C12. Average boiling point range 70°C to 220°C
Average hydrocarbon range of C8 through C18. Average boiling point range 130°C to 320°C
Diesel/Fuel Oil #2
Average hydrocarbon range of C10 through C28. Average boiling point range 170°C to 430°C
Average hydrocarbon range of C22 through C40. Average boiling point range 370°C to 520°C