Gas chromatography is a powerful analytical tool that is used quite often to quantitate the components in various gas samples. This is especially true in the hydrocarbon processing industry. Refineries and chemical plants, as well as natural gas processing facilities, are the main constituents in HPI, and their laboratories are committed to analytical accuracy.

Accuracy in gas sample analysis is not a trivial matter. Gas samples can include components that have significant molecular weight, are in the sample at pressure and mole fraction that push them in the direction of condensing in the sample vessel or just adhering to vessel walls. In either case, components that condense in the sample vessel, or adhere to vessel walls, are underrepresented in subsequent analysis. These components are reported in lower concentrations than what they should be.

Analytical accuracy requires these heavier components to be fairly accounted for in the sample. Heating these heavier components reverses any condensation, extracts them from vessel walls, and returns them to the gas phase so they can be measured accurately.

Cold cylinders may have components "stuck" to their walls

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Heating your sample cylinder returns these components to the gas phase for accurate analysis