1.1 This test method covers the determination of individual compounds and compound classes by percent mass or percent volume with a final boiling point up to 225C using gas chromatography and vacuum ultraviolet detection (GC-VUV). 1.1.1 Typical products encountered in petroleum refining or biofuel operations, such as blend stocks, naphthas, reformates, alkylates, FCC gasoline, liquefied petroleum gas (LPG), alcohols and ethers may be analyzed. 1.1.2 Spark-ignition engine fuels including most commonly blended oxygenates may also be analyzed. 1.1.3 Although the final boiling point of samples as defined by ASTM D86 should not exceed 225C, certain individual hydrocarbons eluting to heptadecane (nC17; BP 302C) can be determined. 1.2 Approximately 150 individual hydrocarbons which comprise the majority of a typical sample can be determined in the range from approximately 0.05 % to 100 % by mass. Hydrocarbons that are not speciated are identified by carbon number and class type. 1.2.1 This test method may not be applicable to all concentrations of individual hydrocarbons; the user must evaluate the spectral response of the hydrocarbon of interest, the amount and proximity of co-eluting hydrocarbons and detector saturation. Quantitation of individual hydrocarbons with concentrations less than 0.1 or greater than 30 % by mass may require verification. 1.2.2 This test method can be used to determine methanol in the range of 0.5 to 3 % by mass, ethanol in the range of 0.5 to 25 % by mass, butanols in the range of 0.5 to 10 % by mass, methyl t-butyl ether (MTBE) in the range of 0.5 to 22 % by mass, ethyl t-butyl ether (ETBE) in the range of 0.5 to 22 % by mass, and t-amyl methyl ether (TAME) in the range of 0.5 to 22 % by mass in spark-ignition engine fuels. 1.2.3 Other compounds containing oxygen, sulfur, nitrogen, and so forth, may also be present, and may co-elute with the hydrocarbons. If determination of other specific compounds is required, supplementation of the spectral library may be necessary. Calibrations and verifications using good laboratory practices be should be performed for any additional compounds of interest. 1.3 This test method can be used to determine bulk group-type composition paraffins, iso-paraffins, olefins, naphthenes, aromatics and oxygenates. Totals by carbon number and totals by carbon number group type are reported. 1.3.1 Olefins may be sub classed into mono-olefins, non-conjugated diolefins, conjugated diolefins and cyclic olefins. 1.3.2 Aromatics may be sub classed into mono-aromatics, diaromatics and naphtheno-aromatics (indans and indenes). 1.4 Individual compounds may not be baseline-separated by the procedure described in this method - i.e., some compounds will coelute. The coelutions are resolved at the detector using VUV absorbance spectra and deconvolution algorithms. Note 1 -- While chromatographic separation is used to minimize the number of coelutions and the deconvolution, due to the nature of the spectroscopic detection, chromatographic baseline peak resolution is not necessary. 1.5 This test method is intended as a type of detailed hydrocarbon analysis (DHA). Incorporation of the GC-VUV data report into commercial DHA software packages with subsequent physical and chemical property calculations and correlations is the responsibility of the DHA software vendor. 1.6 Temporary repeatability has been determined on a limited subset of samples and compounds given in Table X. 1.7 Units - The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
KeywordsGas Chromatography; Vacuum Ultraviolet Absorption Spectroscopy; Gasoline Analysis; Spark-Ignition Engine Fuel Analysis; PIONA; PONA; oxygenates; detailed hydrocarbon analysis; DHA;paraffins; iso-paraffins; olefins; naphthenes; aromatics; naphtha; reformate; alkylate; FCC; liquefied petroleum gas; LPG
Detailed knowledge of refinery stream composition and spark-ignition engine fuels is required by producers and regulators.
The title and scope are in draft form and are under development within this ASTM Committee.Back to Top
Negative Votes Need Resolution