ASTM_C_1274_-_12.pdf

Designation:C127412Standard Test Method forAdvanced Ceramic Specific Surface Area by PhysicalAdsorption1This standard is issued under the fixed designation C1274;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.Scope*1.1 This test method covers the determination of the surfacearea of advanced ceramic materials(in a solid form)based onmultilayer physisorption of gas in accordance with the methodof Brunauer,Emmett,and Teller(BET)(1)2and based onIUPAC Recommendations(1984 and 1994)(2)and(3).Thistest method specifies general procedures that are applicable tomany commercial physical adsorption instruments.This testmethod provides specific sample outgassing procedures forselected common ceramic materials,including:amorphous andcrystalline silicas,TiO2,kaolin,silicon nitride,silicon carbide,zirconium oxide,etc.The multipoint BET(1)equation alongwith the single point approximation of the BET equation arethe basis for all calculations.This test method is appropriate formeasuring surface areas of advanced ceramic powders down toat least 0.05 m2(if in addition to nitrogen,krypton at 77.35 Kis utilized as an adsorptive).1.2 This test method does not include all existing proce-dures appropriate for outgassing of advanced ceramic materi-als.However,it provides a comprehensive summary of proce-dures recommended in the literature for selected types ofceramic materials.The investigator shall determine the appro-priateness of listed procedures.1.3 The values stated in SI units are to be regarded asstandard.State all numerical values in terms of SI units unlessspecific instrumentation software reports surface area usingalternate units.In this case,provide both reported and equiva-lent SI units in the final written report.It is commonly acceptedand customary(in physical adsorption and related fields)toreport the(specific)surface area of solids as m2/g,and,as aconvention,many instruments(as well as certificates of refer-ence materials)report surface area as m2g-1,instead of usingSI units(m2kg-1).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.2.Referenced Documents2.1 ASTM Standards:3D1993 Test Method for Precipitated Silica-Surface Area byMultipoint BET Nitrogen AdsorptionE177 Practice for Use of the Terms Precision and Bias inASTM Test Methods2.2ISO Standards:4ISO 9277 Determination of specific surface area of solids bygas adsorption using the BET methodISO 15901-2:2006 Pore size distribution and porosity ofsolid materials by mercury porosimetry and gas adsorp-tion-Part 2Analysis of mesopores and macropores by gasadsorptionISO 8213:1986Chemical products for industrial use-Sampling techniques-Solid chemical products in the formof particles varying from powders to coarse lumpsISO 18757 Fine ceramics(advanced ceramics,advancedtechnical ceramics)Determination of specific surfacearea of ceramic powders by gas adsorption using the BETmethod3.Terminology3.1 Definitions:53.1.1 adsorbate,nmaterial that has been retained by theprocess of adsorption.3.1.2 adsorbent,nany solid having the ability to concen-trate significant quantities of other substances on its surface.1This test method is under the jurisdiction of ASTM Committee C28 onAdvanced Ceramics and is the direct responsibility of Subcommittee C28.03 onPhysical Properties and Non-Destructive Evaluation.Current edition approved Aug.1,2012.Published November 2012.Originallyapproved in 1994.Last previous edition approved in 2010 as C1274 10.DOI:10.1520/C1274-12.2The boldface numbers in parenthesis refer to the list of references at the end ofthis standard.3For 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.4Available from International Organization for Standardization(ISO),1,ch.dela Voie-Creuse,Case postale 56,CH-1211,Geneva 20,Switzerland,http:/www.iso.ch.5Compilation of ASTM Standard Terminology,8th ed,1994.*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 3.1.3adsorption,nprocess in which molecules are con-centrated on a surface by chemical or physical forces,or both.3.1.4 adsorption isotherm,nrelation between the quantityof adsorbate and the equilibrium(relative)pressure of theadsorptive,at constant temperature.3.1.4.1 DiscussionTypically,the amount adsorbed is pre-sented on an isotherm as volume in cm3STP(S