1、Designation:D708504(Reapproved 2010)1Standard Guide forDetermination of Chemical Elements in Fluid CatalyticCracking Catalysts by X-ray Fluorescence Spectrometry(XRF)1This standard is issued under the fixed designation D7085;the number immediately following the designation indicates the year oforigi
2、nal 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.1NOTEUpdated Scope and text to reflect the use of ppm and SI units editorially in
3、April 2010.1.Scope1.1 This guide covers several comparable procedures for thequantitative chemical analysis of up to 29 elements in fluidcatalytic cracking(FCC)catalyst by X-ray fluorescence spec-trometry(XRF).Additional elements may be added.1.2 This guide is applicable to fresh FCC catalyst,equili
4、b-rium FCC catalyst,spent FCC catalyst,and FCC catalyst fines.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3.1 The units of ppm(mg/kg)are used instead of wt%inTables X2.3-X2.5 for reporting concentration of certain ele-m
5、ents because of industry convention and because most ofthese elements are present at trace levels.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 pr
6、actices and determine the applica-bility of regulatory requirements prior to use.2.Referenced Documents2.1 ASTM Standards:2C982 Guide for Selecting Components for Energy-Dispersive X-Ray Fluorescence(XRF)Systems(With-drawn 2008)3C1118 Guide for Selecting Components for Wavelength-Dispersive X-Ray Fl
7、uorescence(XRF)Systems(With-drawn 2011)3D1977 Test Method for Nickel and Vanadium in FCCEquilibrium Catalysts by Hydrofluoric/Sulfuric Acid De-composition and Atomic Spectroscopic AnalysisE1172 Practice for Describing and Specifying a Wavelength-Dispersive X-Ray SpectrometerE1361 Guide for Correctio
8、n of Interelement Effects inX-Ray Spectrometric AnalysisE1621 Guide for X-Ray Emission Spectrometric AnalysisE1622 Practice for Correction of Spectral Line Overlap inWavelength-Dispersive X-Ray Spectrometry(Withdrawn2006)33.Summary of Guide3.1 The test specimen is prepared with a clean,uniform,flats
9、urface.Two commonly used test methods of preparing testspecimens are listed:briquetting a powder(Test Method A,Sections 8-15)and fusing a powder into a glass bead(TestMethod B,Sections 16-23).This surface of the fused orbriquetted specimen is irradiated with a primary source of Xrays.The secondary X
10、 rays produced in the specimen arecharacteristic of the chemical elements present in the speci-men.Two types of XRF instrumentation may be used to collectand process the X-ray spectra.Using a wavelength-dispersiveX-ray spectrometer,the secondary X rays produced in thespecimen are dispersed according
11、 to their wavelength bymeans of crystals or synthetic multilayers.The X-ray intensi-ties are measured by detectors set at selected wavelengths andrecorded as counts(number of X rays impinging on thedetector per unit time).Concentrations of the elements aredetermined from the measured intensities usi
12、ng calibrationcurves prepared from suitable reference materials.Using anenergy-dispersive X-ray spectrometer,the secondary X raysproduced in the specimen are sent to a detector where the entireX-ray spectrum is electronically sorted according to the X-rayenergy and processed into counts using a mult
13、ichannel ana-lyzer.The principal advantages of the wavelength-dispersiveX-ray spectrometer are resolution and detection limit.Theprincipal advantages of the energy-dispersive X-ray spectrom-eter are speed and a generally lower equipment cost.1This guide is under the jurisdiction of ASTM Committee D3
14、2 on Catalysts andis the direct responsibility of Subcommittee D32.03 on Chemical Composition.Current edition approved April 1,2010.Published May 2010.Originallyapproved in 2004.Last previous edition approved in 2004 as D7085041.DOI:10.1520/D7085-04R10E01.2For referenced ASTM standards,visit the AST
15、M 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.Copyright ASTM Internation
16、al,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.Significance and Use4.1 The chemical composition of fresh FCC catalyst andequilibrium FCC catalyst is a predictor of catalyst perfor-mance.The analysis of catalyst fines also provides informationon the performance of the FCC unit and the fines collectiondevice(s).4.2 The chemical composition of equilibrium FCC catalystis a measure of the hazardous nature or toxicity of the materialfor purposes of disposal or se