1、Designation:D627707(Reapproved 2012)Standard Test Method forDetermination of Benzene in Spark-Ignition Engine FuelsUsing Mid Infrared Spectroscopy1This standard is issued under the fixed designation D6277;the number immediately following the designation indicates the year oforiginal adoption or,in t
2、he case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the per-centage of benzene in spark-ignition e
3、ngine fuels.It is appli-cable to concentrations from 0.1 to 5 volume%.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It i
4、s theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1298 Test Method for Density,Relative Density,or APIGravity of Crude Petroleum and
5、 Liquid Petroleum Prod-ucts by Hydrometer MethodD4052 Test Method for Density,Relative Density,and APIGravity of Liquids by Digital Density MeterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD4307 Practice
6、 for Preparation of Liquid Blends for Use asAnalytical StandardsD5769 Test Method for Determination of Benzene,Toluene,and Total Aromatics in Finished Gasolines by GasChromatography/Mass SpectrometryD5842 Practice for Sampling and Handling of Fuels forVolatility MeasurementD5854 Practice for Mixing
7、and Handling of Liquid Samplesof Petroleum and Petroleum ProductsE168 Practices for General Techniques of Infrared Quanti-tative AnalysisE1655 Practices for Infrared Multivariate QuantitativeAnalysisE2056 Practice for Qualifying Spectrometers and Spectro-photometers for Use in Multivariate Analyses,
8、CalibratedUsing Surrogate Mixtures3.Terminology3.1 Definitions:3.1.1 multivariate calibrationa process for creating acalibration model in which multivariate mathematics is appliedto correlate the absorbances measured for a set of calibrationsamples to reference component concentrations or propertyva
9、lues for the set of samples.3.1.1.1 DiscussionThe resultant multivariate calibrationmodel is applied to the analysis of spectra of unknown samplesto provide an estimate of the component concentration orproperty values for the unknown sample.3.1.1.2 DiscussionIncluded in the multivariate calibrationa
10、lgorithms are Partial Least Squares,Multilinear Regression,and Classical Least Squares Peak Fitting.3.1.2 oxygenatean oxygen-containing organic compoundwhich may be used as a fuel or fuel supplement,for example,various alcohols and ethers.4.Summary of Test Method4.1 Asample of spark-ignition engine
11、fuel is introduced intoa liquid sample cell.Abeam of infrared light is imaged throughthe sample onto a detector,and the detector response isdetermined.Wavelengths of the spectrum,that correlate highlywith benzene or interferences,are selected for analysis usingselective bandpass filters or by mathem
12、atically selecting areasof the whole spectrum.A multivariate mathematical analysisconverts the detector response for the selected areas of thespectrum of an unknown to a concentration of benzene.5.Significance and Use5.1 Benzene is a compound that endangers health,and theconcentration is limited by
13、environmental protection agenciesto produce a less toxic gasoline.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.04.0F on Absorption Spectroscopic Methods.Current edition approved Nov.1,2012.Pu
14、blished November 2012.Originallyapproved in 1998.Last previous edition approved in 2007 as D627707.DOI:10.1520/D6277-07R12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer t
15、o the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.2 This test method is fast,simple to run,and inexpensive.5.3 This test method is applicable for quality control in theproduction an
16、d distribution of spark-ignition engine fuels.6.Interferences6.1 The primary spectral interferences are toluene and othermonosubstituted aromatics.In addition,oxygenates can inter-fere with measurements made with filter apparatus.Properchoice of the apparatus,proper design of a calibration matrix,and proper utilization of multivariate calibration techniquescan minimize these interferences.7.Apparatus7.1 Mid-IR Spectrometric Analyzer(of one of the followingtypes):7.1.1 Filter-based Mid-IR Test Ap
