1、Designation: D7653 18Standard Test Method forDetermination of Trace Gaseous Contaminants in HydrogenFuel by Fourier Transform Infrared (FTIR) Spectroscopy1This standard is issued under the fixed designation D7653; the number immediately following the designation indicates the year oforiginal adoptio
2、n 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.1. Scope1.1 This test method employs an FTIR gas analysis systemfor the determination o
3、f trace impurities in gaseous hydrogenfuels relative to the hydrogen fuel quality limits described inSAE TIR J2719 (April 2008) or in hydrogen fuel qualitystandards from other governing bodies. This FTIR method isused to quantify gas phase concentrations of multiple targetcontaminants in hydrogen fu
4、el either directly at the fuelingstation or on an extracted sample that is sent to be analyzedelsewhere. Multiple contaminants can be measured simultane-ously as long as they are in the gaseous phase and absorb in theinfrared wavelength region. The detection limits as well asspecific target contamin
5、ants for this standard were selectedbased upon those set forth in SAE TIR J2719.1.2 This test method allows the tester to determine whichspecific contaminants for hydrogen fuel impurities that are inthe gaseous phase and are active infrared absorbers which meetor exceed the detection limits set by S
6、AE TIR J2719 for theirparticular FTIR instrument. Specific target contaminantsinclude, but are not limited to, ammonia, carbon monoxide,carbon dioxide, formaldehyde, formic acid, methane, ethane,ethylene, propane, and water. This test method may be ex-tended to other impurities provided that they ar
7、e in the gaseousphase or can be vaporized and are active infrared absorbers.1.3 This test method is intended for analysis of hydrogenfuels used for fuel cell feed gases or for internal combustionengine fuels. This method may also be extended to the analysisof high purity hydrogen gas used for other
8、applicationsincluding industrial applications, provided that target impuri-ties and required limits are also identified.1.4 This test method can be used to analyze hydrogen fuelsampled directly at the point-of-use from fueling stationnozzles or other feed gas sources. The sampling apparatusincludes
9、a pressure regulator and metering valve to provide anappropriate gas stream for direct analysis by the FTIR spec-trometer.1.5 This test method can also be used to analyze samplescaptured in storage vessels from point-of-use or other sources.Analysis of the stored samples can be performed either in a
10、mobile laboratory near the sample source or in a standardanalytical laboratory.1.6 A test plan should be prepared that includes (1) thespecific impurity species to be measured, (2) the concentrationlimits for each impurity species, and (3) the determination ofthe minimum detectable concentration for
11、 each impurity spe-cies as measured on the apparatus before testing.1.7 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.7.1 ExceptionAll values are based upon common termsused in the industry of those particular values and whe
12、n notconsistent with SI units, the appropriate SI unit will beincluded in parentheses after the common value usage (4.4, 7.8,7.9, 10.5, and 11.6).1.8 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 stan
13、dard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision o
14、n Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D5287 Practice for Automatic Sampling of Gaseous Fuels1This test method is under the ju
15、risdiction ofASTM Committee D03 on GaseousFuels and is the direct responsibility of Subcommittee D03.14 on Hydrogen andFuel Cells.Current edition approved Dec. 1, 2018. Published February 2019. Originallyapproved in 2010. Last previous edition approved in 2010 as D7653 10. DOI:10.1520/D7653-18.2For
16、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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700,
17、West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World
18、 Trade Organization Technical Barriers to Trade (TBT) Committee.1D6348 Test Method for Determination of Gaseous Com-pounds by Extractive Direct Interface Fourier TransformInfrared (FTIR) SpectroscopyD7606 Practice for Sampling of High Pressure Hydrogenand Related Fuel Cell Feed Gases2.2 SAE Document
19、:3SAE TIR J2719 Informational Report on the Developmentof a Hydrogen Quality Guideline for Fuel Cell Vehicles2.3 EPA Documents:4EPA 40 CFR Protection of the Environment, Appendix B toPart 136 Definition and Procedure for the Determinationof the Method Detection LimitEPA 40 CFR Protection of the Envi
20、ronment, Appendix B toPart 60: Performance Specification 15 Performance Speci-fication for Extractive FTIR Continuous Emissions Moni-toring Systems in Stationary Sources3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 analytical interference, nthe physical effects of su-perimpo
21、sing two or more light waves.3.1.1.1 DiscussionAnalytical interferences occur whentwo or more compounds have overlapping absorbance bands intheir infrared spectra.3.1.2 analytical algorithm, nthe method used to quantifythe concentration of the target contaminants and interferencesin each FTIR Spectr
22、um.3.1.2.1 DiscussionThe analytical algorithm should ac-count for the analytical interferences by conducting the analy-sis in a portion of the infrared spectrum that is the most uniquefor that particular compound.3.1.3 apodization, na mathematical transformation carriedout on data received from an i
23、nterferometer to reduce the sidelobes of the measured peaks.3.1.3.1 DiscussionThis procedure alters the instrumentsresponse function. There are various types of transformation;the most common forms are boxcar, triangular, Happ-Genzel,and Norton-Beer functions.3.1.4 background spectrum, nthe spectrum
24、 taken in theabsence of absorbing species or sample gas, typically con-ducted using dry nitrogen or zero air in the gas cell.3.1.5 classical least squares (CLS), ncommon method ofanalyzing multicomponent infrared spectra by scaled absor-bance subtraction, also referred to as K-Matrix.3.1.6 constitue
25、nt, ncomponent (or compound) foundwithin a hydrogen fuel mixture.3.1.7 contaminant, nimpurity that adversely affects thecomponents within the fuel cell system or the hydrogen storagesystem.3.1.8 dry nitrogen (or dry N2), nnitrogen gas with a dewpoint at or below 60 C.3.1.9 dynamic calibration, ncali
26、bration of an analyticalsystem using certified calibration gas standards that are dilutedto known concentration.3.1.10 FCV, nHydrogen fuel cell vehicle.3.1.11 Fourier Transform Infrared (FTIR), ntypically re-fers to a type of infrared spectrometer which incorporates aMichelson interferometer to modu
27、late the infrared radiationbefore probing the sample.3.1.11.1 DiscussionThe resultant radiation is then mea-sured with an infrared detector and the resulting signal isdecoded using a Fourier transform algorithm to compute theinfrared spectrum.3.1.12 fuel cell grade hydrogen, nhydrogen satisfying the
28、specifications in SAE TIR J2719.3.1.13 gaseous fuel, nhydrogen gas intended for use as afuel cell feed gas or as a fuel for internal combustion engines.3.1.14 gauge pressure, npressure measured above ambi-ent atmospheric pressure; zero gauge pressure is equal to theambient atmospheric (barometric) p
29、ressure (psig).3.1.15 path length, nthe distance that the sample gasinteracts with the infrared radiation.3.1.16 poisoning, vprocess by which catalysts are madeinoperative due to the activity of substances such as hydrogensulfide or other sulfur substances that can bind to a componentin the catalyst
30、 (such as a noble metal like platinum) used in thefuel cell.3.1.17 proton exchange membrane fuel cells (PEMFCs),nPEMFC is an electrochemical apparatus that uses an anodeand cathode to convert H2and O2into electricity.3.1.18 purified nitrogen (or purified N2), nnitrogen gasthat is purified to Ultra-H
31、igh Purity Grade (99.9995 %) orequivalent, containing total impurities 35 C) to avoidfluctuations or temperature mismatch due to changes in theambient temperature. Be sure to use the same FTIR spectralresolution and apodization function for calibrations and mea-surements. The gas cell path length is
32、 chosen to provideadequate sensitivity while maintaining maximum absorbanceFIG. 3 Apparatus for Measuring Samples from High Pressure Storage Containers. Line Switching Valve (V), Needle Valve (NV)D7653 186unit (AU) values for the quantification region to be at or under1.0 AU. If necessary, the maxim
33、um absorbance requirementcan be met by choosing analytical regions that exclude strongabsorption features. The number of FTIR scans (or measure-ment time) can be increased to improve detection limits.Record all settings and actual gas cell absolute pressure andtemperature for each calibration spectr
34、um.9.1.3 Determine the Number of Gas Cell Volumes Requiredto Flush the FTIR Gas CellThe Environmental ProtectionAgency (EPA) recommends 5 cell volumes are adequate tofully flush the gas cell of the sample (See EPA 40 CFRProtection of the Environment, Appendix B to Part 60). For aflow rate of 1 L per
35、 min (LPM) and a gas cell volume of200 mL the number of cell volumes would be 1.0 LPM/0.2 L= 5 volumes flushed per 1 min. For a larger cell volume of500 mL for the same flow rate you would only achieve1.0 LPM 0.5 L = 2 volumes flushed per 1 min. Therefore theamount of time required to completely flu
36、sh the gas samplefrom the gas cell is dependant upon the gas cell internal volumeand the gas sample flow rate. For faster data acquisition asmaller gas sample volume is desired or a faster flow rate canbe used, but that must be balanced by the amount of samplethat is resident in the gas sample chamb
37、er/cylinder that wascollected.9.1.4 Prior to collecting the calibration spectra verify theFTIR performance is within acceptable limits following theinstructions in AnnexA1 as well as those specified by the FTIRmanufacturer.9.2 Collect Calibration Spectra for Species in CalibrationGas Cylinders:9.2.1
38、 Purge the gas blending apparatus and FTIR gas cellwith purified H2. Monitor for one or more surrogate contami-nant species (generally H2O is selected) using the FTIR toverify that the reported concentrations have reached a mini-mum and stable value. As needed a new background spectrumis acquired.9.
39、2.2 Program the gas blending apparatus to prepare therequired concentration mixtures while maintaining a relativelyconstant flow rate to prevent an increase in pressure in theFTIR gas cell. For each blend, allow the mixture to flowthrough the FTIR gas cell purging at the required number ofcell volum
40、es as determined in 9.1.3.9.2.3 Collect at least three calibration spectra for eachconcentration blend level. The three spectra can later be used toverify that the calibration gas concentration was within 62%of the calibration gas value. Record the FTIR settings, gas celltemperature, gas cell absolu
41、te pressure, and gas cell pathlength. Repeat this process for each desired concentration foreach species in the calibration gas cylinder.9.2.4 As desired, a single set of calibration gas blends canbe prepared that spans the desired range for all species in thecalibration gas bottle providing that th
42、ere is no spectral overlapbetween the target contaminants in the blend. In general it isnot possible or reasonable to combine all of the componentsinto a single standard but a sub set of contaminants that do nothave spectral overlaps can be combined. For example, hydro-carbons can be blended with NO
43、, N2O, CO, or CO2(forexample, methane and CO or methane and CO2) and have nooverlap within the usable infrared region. Care should be takento ensure that contaminants in the blends do not react with eachother.9.3 Collect Calibration Spectra for Species from Perme-ation Tubes:9.3.1 Purge the gas blen
44、ding apparatus and FTIR gas cellwith purified H2. Monitor for one or more surrogate contami-nant species (for example, H2O which tends to be more sticky)using the FTIR to verify that the reported concentrations havereached a minimum and stable value such as applying an f-testto determine the values
45、are no longer significant. As needed anew background spectrum is acquired.9.3.2 Set the temperature of the permeation tube oven asdirected by the permeation tube manufacturer and set the massflow controllers as required to prepare the desired concentra-tion. The use of permeation tubes at ambient te
46、mperature is notacceptable as this will result in excessive variability in perme-ation rates due to a lack of fine temperature control. Asnecessary, the output flow from the permeation oven can besplit using the output mass flow controller and a backpressureregulator in order to prepare lower concen
47、tration standards. Foreach blend, allow the mixture to flow through the FTIR gas cellpurging at the required number of cell volumes as defined in9.1.3.9.3.3 Collect at least three calibration spectra for eachcontaminant (impurity) concentration. The three spectra can beused to verify that the calibr
48、ation gas concentration was notchanging within 62 %. Record the FTIR settings, gas celltemperature, gas cell absolute pressure, and gas cell pathlength. Also record the permeation tube serial number, concen-tration calculation, oven temperature, and flow conditions.Repeat this process for each desir
49、ed concentration for eachcontaminant species that requires a permeation tube to be used.9.3.4 Follow Annex A3 for more details on the creation ofthe FTIR Reference Spectra.9.4 Prepare Analytical Methods for Each Impurity Species:9.4.1 For gas impurity analysis the main analytical methodused is based upon Classical Least Squares (CLS) algorithms.This method requires that each component that might bepresent in the final gas sample be included in the full analysismethod. A calibration method is created for each componentusing the ten or more concentrations
