EXPLANATION
This test method covers the determination of seven saturated hydrocarbon types and one aromatic type using high ionizing voltage mass spectrometry. It covers the analysis of saturate petroleum fractions with average carbon numbers of 16 through 32. Samples must be nonolefinic and must contain less than 5 volume % monoaromatics. When used together with Test Method ASTM D3239 (see following), this test method provides a detailed analysis of the hydrocarbon composition of such materials.
TEST SUMMARY
The relative abundance of these hydrocarbons in petroleum saturate fractions is determined by mass spectrometry using a summation of mass fragment groups most characteristic of each molecular type. Calculations are carried out by the use of inverted matrices that are specific for any average carbon number. The saturate fraction necessary for this test is obtained by liquid elution chromatography Test Method ASTM D2549.
TEST PRECISION
Based on a cooperative study, the following precisions were obtained.
This test method has no bias.