ASTM_D_6761_-_07_2012.pdf

Designation:D676107(Reapproved 2012)Standard Test Method forDetermination of the Total Pore Volume of Catalysts andCatalyst Carriers1This standard is issued under the fixed designation D6761;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.1.Scope1.1 This test method covers the determination of the totalpore volume of catalysts and catalyst carriers,that is,thevolume of pores having pore diameter between approximately14 m and 0.4 nm(4).1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 WARNINGMercury has been designated by manyregulatory agencies as a hazardous material that can causecentral nervous system,kidney and liver damage.Mercury,orits vapor,may be hazardous to health and corrosive tomaterials.Caution should be taken when handling mercury andmercury containing products.See the applicable product Ma-terial Safety Data Sheet(MSDS)for details and EPAswebsitehttp:/www.epa.gov/mercury/faq.htmfor addi-tional information.Users should be aware that selling mercuryand/or mercury containing products into your state or countrymay be prohibited by law.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.Specific hazardstatements are given in Section 8.Warning statements aregiven in 9.1.4,9.1.7,and 9.1.11.2.Referenced Documents2.1 ASTM Standards:2D3766 Terminology Relating to Catalysts and CatalysisE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE456 Terminology Relating to Quality and StatisticsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Definitions:3.1.1 particle volumethe volume of a particle includingpores into which mercury cannot penetrate at ambient pressure(smaller than approximately 14 m diameter pore mouth).3.1.2 true volumethe volume of a particle,includingpores,into which helium cannot penetrate(smaller than aboutapproximately 0.4 nm(4)diameter pore mouth).3.1.3 Other definitions and terms used in this test methodare defined in Terminology D3766.3.2 Symbols for Mercury Intrusion:W=mass of sampleWc=mass of sealed empty sample cellWC=mass of sealed sample cell filled with mercuryWs=mass of sealed sample cell with sampleWS=mass of sealed sample cell with sample filled withmercuryVHgC=volume of mercury in empty sample cell(volume ofsample cell)VHgS=volume of mercury in cell with sampleVSHg=sample volume,cm3VHg=specific sample volumeVP=particle volumeWb=weight mercury reservoir after filling burette withsampleWb=mass of mercury reservoir after filling burette with-out sample3.3 Symbols for Helium Pycnometry:VC=volume of sample cell and associated tubing,cm3VR=reference volume,cm3VSHe=sample volume,cm3VCyl=volume of calibration cylinder,cm3VSTD=volume of calibration standard,cm3VHe=specific sample volumeP1=pressure in empty sample cell,psig or pascals1This test method is under the jurisdiction of ASTM Committee D32 onCatalysts and is the direct responsibility of Subcommittee D32.02 on Physical-Mechanical Properties.Current edition approved May 1,2012.Published July 2012.Originally approvedin 2002.Last previous edition approved in 2007 as D676107.DOI:10.1520/D6761-07R12.2For 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 to 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 P2=pressure in empty sample cell,after the referencevolume has been included in the system,psig orpascalsP1=pressure in sample cell with sample or calibrationstandard before the reference volume has beenincluded in the system,psig or pascalsP2=pressure with sample or calibration standard in thesample cell,after the reference volume has beenincluded in the system,psig or pascalsW1=tare weight of sample cup,gW2=mass of sample+tare weight of sample cup,gW3=mass of sample,gP.V.=pore volume4.Summary of Test Method4.1 The total pore volume of a catalyst or catalyst carrier isdetermined as the difference between the particle volume andthe true volume,measured by mercury intrusion and heliumpycnometry,respectively.The particle volume is determinedby mercury intrusion at ambient pressure and the true volumeis determined by helium displacement at pressures aboveambient.5.Significance and Use5.1 This test method provides for the measurement ofvolume of pores that are in the range of c