ASTM_D_3701_-_01_2012.pdf

Designation:D370101(Reapproved 2012)Standard Test Method forHydrogen Content of Aviation Turbine Fuels by LowResolution Nuclear Magnetic Resonance Spectrometry1This standard is issued under the fixed designation D3701;the number immediately following the designation indicates the year oforiginal adoption or,in the 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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method covers the determination of the hydro-gen content of aviation turbine fuels.1.2 Use Test Methods D4808 for the determination ofhydrogen in other petroleum liquids.1.3 The values stated in SI units are to be regarded asstandard.The preferred units are mass percent hydrogen.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is 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 6.1.2.Referenced Documents2.1 ASTM Standards:2D1322 Test Method for Smoke Point of Kerosine andAviation Turbine FuelD1740 Test Method for Luminometer Numbers of AviationTurbine Fuels(Withdrawn 2006)3D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4808 Test Methods for Hydrogen Content of LightDistillates,Middle Distillates,Gas Oils,and Residua byLow-Resolution Nuclear Magnetic Resonance Spectros-copy3.Summary of Test Method3.1 A sample of the material is compared in a continuouswave,low-resolution,nuclear magnetic resonance spectrom-eter with a reference standard sample of a pure hydrocarbon.The results from the integrator on the instrument are used as ameans of comparing the theoretical hydrogen content of thestandard with that of the sample,the result being expressed asthe hydrogen content(percent mass basis)in the sample.4.Significance and Use4.1 The combustion quality of aviation turbine fuel hastraditionally been controlled in specifications by such tests assmoke point(see Test Method D1322),smoke volatility index,aromatic content of luminometer number(see Test MethodD1740).Evidence is accumulating that a better control of thequality may be obtained by limiting the minimum hydrogencontent of the fuel.4.2 Existing methods allow the hydrogen content to becalculated from other parameters or determined by combustiontechniques.The method specified provides a quick,simple,andmore precise alternative to these methods.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.03 on Elemental Analysis.Current edition approved April 15,2012.Published April 2012.Originallyapproved in 1978.Last previous edition approved in 2006 as D370101(2006).DOI:10.1520/D3701-01R12.2For 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 standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Apparatus5.1 Nuclear Magnetic Resonance Spectrometer4A low-resolution continuous-wave instrument capable of measuring anuclear magnetic resonance of hydrogen atoms,and fitted with:5.1.1 Excitation and Detection Coil,of suitable dimensionsto contain the test cell.5.1.2 Electronic Unit,to control and monitor the magnet andcoil and containing:5.1.2.1 Circuits,to control and adjust the radio frequencylevel and audio frequency gain.5.1.2.2 Integrating Counter,with variable time period inseconds.5.2 Conditioning BlockA block of aluminum alloy drilledwith holes of sufficient size to accommodate the test cells withthe mean height of the sample being at least 20 mm below thetop of the conditioning block(see Fig.1).5.3 Test CellsNessler-type tubes of approximately100-mL capacity with a nominal external diameter of 34 mmand a nominal internal diameter of 31 mm marked at a distanceof approximately 51 mm above the bottom of the tube by a ringaround the circumference.The variation between the internaldiameters of the test cells used for the sample and referencematerial should not be greater than 60.5 mm.NOTE1To avoid potential difficulties with tightness when the test cellis introduced into the magnet coil,users are cautioned to avoid test cellsthat have nominal external diameters that are greater than 34.2 mm.5.4 Polytetrafluoroethylene(PTFE)Plugs for Closing TestCellsPlugs as shown in Fig.1 made from pure PTFE and atight fit in the test cells.5.5 Insertion R