1、Designation: C 1069 09Standard Test Method forSpecific Surface Area of Alumina or Quartz by NitrogenAdsorption1This standard is issued under the fixed designation C 1069; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、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 specificsurface area of aluminas and silicas used in the manufacture
3、 ofceramics. The test method is a general one, permitting the useof any modern commercial nitrogen adsorption apparatus butstrictly defining the outgassing procedure. Calculations arebased on the Brunauer-Emmett-Teller (BET) equation.1.2 The values stated in SI units are to be regarded asstandard. N
4、o other units of measurement are included in thisstandard.1.3 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-bil
5、ity of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E 173 Practice for Conducting Interlaboratory Studies ofMethods for Chemical Analysis of Metals33. Summary3.1 An appropriate size sample is degassed for1hat423Kbefore proceeding with the analysis as prescribed by t
6、hemanufacturer of the instrument used. The sample is accuratelyweighed after analysis.3.2 Calculations are based on the BET equations, adaptedwhere necessary for the equipment being used. The cross-sectional area of the nitrogen molecule is taken as 0.162 nm2.4. Significance and Use4.1 Both sellers
7、and purchasers of alumina and quartz willfind the test method useful to determine the specific surfacearea and indirectly as a measure of the particle size for materialspecifications, manufacturing control, and research and devel-opment.5. Apparatus5.1 Specific Surface Area Analyzer, recently (after
8、 1970)manufactured commercial equipment employing low-temperature (77 K) nitrogen adsorption. This test method maybe dynamic or static.5.2 Degassing Equipment, suitable to the instrument used.5.3 Analytical Balance, having a sensitivity of 1.0 mg.6. Reagents and Materials6.1 Liquid Nitrogen.6.2 Cyli
9、nder of compressed nitrogen gas, high purity asspecified by manufacturer, with pressure regulator.6.3 Cylinder of compressed helium gas, high purity asspecified by manufacturer, with pressure regulator, for staticinstruments or for dynamic instruments having gas mixingability and employing the multi
10、point procedure or,6.4 Cylinder of compressed, approximately 0.30 mol frac-tion, nitrogen in helium with pressure regulator, for otherdynamic instruments employing the single point procedure.7. Procedure7.1 Sample PreparationBlend the gross sample very well.For non-free-flowing materials mechanical
11、agitation is neces-sary (for example, V-type blender with intensifier). If samplesplitting of free-flowing materials is necessary, use a spinningriffler.7.2 Sample Degassing7.2.1 Sample size is related to the equipment being used andshall conform to the equipment manufacturers recommenda-tions for h
12、ighest precision.7.2.2 The degassing technique (for example, vacuum, no-vacuum) shall conform to the equipment manufacturers rec-ommendations.7.2.3 The degassing temperature shall be1hat423K.7.2.4 Samples must be analyzed immediately after degas-sing.7.3 AnalysisThe analysis procedure recommended by
13、 themanufacturer as their most precise shall be followed.1This test method is under the jurisdiction ofASTM Committee C21 on CeramicWhitewares and Related Products and is the direct responsibility of SubcommitteeC21.04 on Raw Materials.Current edition approved Jan. 1, 2009. Published February 2009.
14、Originallyapproved in 1986. Last previous edition approved in 1997 as C 1069 86 (2004)1.2For 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 Summa
15、ry page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United Stat
16、es.8. Calculations8.1 The procedure recommended by the manufacturer asbeing the most complete shall be followed.9. Report9.1 Report the following information:9.1.1 ResultsIn units of m2/g.9.1.2 Specific surface area as the average of two determi-nations, each made on separately degassed samples. If
17、theresults do not agree within 5 % the procedure should bereviewed, the equipment checked, and the test repeated a thirdtime.9.1.3 From a practical standpoint it is recommended that thefollowing guidelines be used in reporting data:9.1.3.1 From 1 to 99 m2/gno more than two significantfigures.9.1.3.2
18、 From 100 to 200 m2/gto the nearest 1 m2/g.9.1.3.3 From 200 m2/g and aboveto the nearest 5 m2/g.10. Precision and Bias10.1 PrecisionSix laboratories cooperated in a testingprogram involving various materials having specific surfaceareas ranging from 1 to 200 m2/g. The determinations weremade in dupl
19、icate on separate samples and days. Practice E 173was used to obtain the analyses of variance in Table 1.10.2 BiasNo absolute method for surface area determina-tions is recognized and, therefore, it is not possible to discussbias of results obtained.11. Keywords11.1 alumina; nitrogen adsorption; par
20、ticle size; quartzSUMMARY OF CHANGESCommittee C21 has identified the location of selected changes to this standard since the last issue(C 106986(2004)1) that may impact the use of this standard.(1) Addition of 1.2 describing the use of units in this testmethod, with renumbering of the subsequent sec
21、tions of thescope.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement o
22、f such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for
23、additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known t
24、o the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at
25、 the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).TABLE 1 Analyses of VarianceSurfaceArea,m2/gARepeatabilityInterval,R1,m2/gReproducibilityInterval,R2,m2/g1.1 0.05 0.191.3 0.12 0.268.4 0.40 2.079.3 0.44 0.8625 0.63 5.2101 4.8 11.0205 8.2 33.2AAverages from round-robin study.C1069092
