1、Designation:D242504(Reapproved 2009)Standard Test Method forHydrocarbon Types in Middle Distillates by MassSpectrometry1This standard is issued under the fixed designation D2425;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the yea
2、r 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 an analytical scheme using themass spectrometer to determine the hydrocarbon types presentin v
3、irgin middle distillates 204 to 343C(400 to 650F)boilingrange,5 to 95 volume%as determined by Test Method D86.Samples with average carbon number value of paraffins be-tween C12and C16and containing paraffins from C10and C18can be analyzed.Eleven hydrocarbon types are determined.These include:paraffi
4、ns,noncondensed cycloparaffins,con-densed dicycloparaffins,condensed tricycloparaffins,alkylben-zenes,indans or tetralins,or both,CnH2n-10(indenes,etc.),naphthalenes,CnH2n-14(acenaphthenes,etc.),CnH2n-16(acenaphthylenes,etc.),and tricyclic aromatics.NOTE1This test method was developed on Consolidate
5、d Electrody-namics Corporation Type 103 Mass Spectrometers.1.2 The values stated in SI units are to be regarded as thestandard.The inch-pound units given in parentheses are forinformation only.1.3 This standard does not purport to address all of thesafety problems,if any,associated with its use.It i
6、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.For a specificwarning statement,see 10.1.2.Referenced Documents2.1 ASTM Standards:2D86 Test Method for Distillation of Petrol
7、eum Products atAtmospheric PressureD2549 Test Method for Separation of Representative Aro-matics and Nonaromatics Fractions of High-Boiling Oilsby Elution Chromatography3.Terminology3.1 The summation of characteristic mass fragments aredefined as follows:71(paraffins)=total peak height of m/e+71+85.
8、67(mono or noncondensed polycycloparaffins,orboth)=total peak height of m/e+67+68+69+81+82+83+96+97.123(condensed dicycloparaffins)=total peak height ofm/e+123+124+137+138+etc.up to 249+250.149(condensed tricycloparaffins)=total peak height ofm/e+149+150+163+164+etc.up to 247+248.91(alkylbenzenes)=t
9、otalpeakheightofm/e+91+92+105+106+etc.up to 175+176.103(indans or tetralins,or both)=total peak height ofm/e+103+104+117+118+etc.up to 187+188.115(indenes or CnH2n-10,or both)=total peak height ofm/e+115+116+129+130+etc.up to 185+186.128(naphthalene)=total peak height of m/e+128.141(naphthalenes)=to
10、talpeakheightofm/e+141+142+155+156+etc.up to 239+240.153(acenaphthenes or CnH2n-14,or both)=total peakheight of m/e+153+154+167+168+etc.up to251+252.151(acenaphthylenes or CnH2n-16,or both)=total peakheight of m/e+151+152+165+166+etc.up to249+250.177(tricyclic aromatics)=total peak height of m/e+177
11、+178+191+192+etc.up to 247+248.4.Summary of Test Method4.1 Samples are separated into saturate and aromatic frac-tions by Test Method D2549,and each fraction is analyzed bymass spectrometry.The analysis is based on the summation ofcharacteristic mass fragments to determine the concentration ofhydroc
12、arbon types.The average carbon numbers of the hydro-carbon types are estimated from spectral data.Calculations aremade from calibration data dependent upon the average carbonnumber of the hydrocarbon types.The results of each fractionare mathematically combined according to their mass fractionsas de
13、termined by the separation procedure.Results are ex-pressed in mass percent.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricantsand is the direct responsibility of SubcommitteeD02.04.0M on Mass Spectroscopy.Current edition approved Oct.1,2009.Publishe
14、d November 2009.Originallyapproved in 1965.Last previous edition approved in 2004 as D242504.DOI:10.1520/D2425-04R09.2For 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 to the
15、standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 NOTE2Test Method D2549 is presently applicable only to sampleshaving 5%points of 232C(450F)or greater.5.Significance and Use5.1 Aknowledge
16、of the hydrocarbon composition of processstreams and petroleum products boiling within the range of 400to 650F(204 to 343C)is useful in following the effect ofchanges in process variables,diagnosing the source of plantupsets,and in evaluating the effect of changes in compositionon product performance properties.6.Interferences6.1 Nonhydrocarbon types,such as sulfur and nitrogen-containing compounds,are not included in the matrices for thistest method.If these nonhydrocarbon types are present to
