ASTM_D_4781_-_03_2013.pdf

Designation:D478103(Reapproved 2013)Standard Test Method forMechanically Tapped Packing Density of Fine CatalystParticles and Catalyst Carrier Particles1This standard is issued under the fixed designation D4781;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 me-chanically tapped packing density of fine catalyst and catalystcarrier particles smaller than 0.8 mm in diameter.1.2 The values stated in SI units are to be regarded asstandard.No 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-bility of regulatory limitations prior to use.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 DefinitionsSee Terminology D3766.4.Summary of Test Method4.1 A preconditioned sample of dried fine catalyst or cata-lyst carrier particles is tapped in a graduated cylinder.Themechanically tapped packing density is determined from theknown mass and tapped volume.5.Significance and Use5.1 This test method is for measuring the mechanicallytapped packing density of powders that are smaller than 0.8mm in diameter,such as Fluidized Catalytic Cracking Catalysts(FCC).6.Apparatus6.1 Graduated Cylinder,capacity 100 mL.6.2 Holder,acylinder holder weighing 454 g.6.3 Tapping Device,consisting of a baseplate with wormdrive,with specifications of 250 r/min camshaft speed,tappingstroke travel of 3.2 mm.6.4 Counter,a four-digit adjustable counter,which can bepreset to deliver number of taps between 1 and 9999.6.5 Desiccator,with a desiccant grade molecular sieve suchas 4A.6.6 Balance,having a sensitivity of 0.1 g.6.7 Drying Oven.7.Procedure7.1 Heat an adequate sample at 400 6 15C for not less than3 h.Normally,this treatment can take place in air.However,inthe case of materials that might react with air at elevatedtemperature(such as prereduced catalysts)the heat treatmentshould take place in an inert atmosphere.After heating,coolthe test sample in a desiccator or other suitable container toeliminate the possibility of moisture adsorption prior to testing.NOTE1These conditions may not be appropriate for all materials.NOTE2Since many catalyst formulations are strong adsorbents,theuse of 4A indicating(cobalt-treated)molecular sieves as a desiccatingmedium is recommended.The desiccant should be regenerated at 220 to260C,as required.NOTE3Multiple samples can be pretreated but must be desiccatedprior to analysis.7.2 Carefully pour between 90 and 100 mL of the testspecimen into the tared-graduated cylinder using a funnel.Toensure proper level,rotate the funnel while pouring the testspecimen.Weigh immediately to the nearest tenth of a gram.The entire transfer time should be between 35 and 50 s.7.3 Preset the counter to 1000 taps.1This 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 March 1,2013.Published March 2013.Originallyapproved in 1988.Last previous edition approved in 2008 as D478103(2008).DOI:10.1520/D4781-03R13.2For 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 7.4 Start the tapping device.7.5 When tapping is completed,read the tapped volume,V,to the nearest 1 mL by estimating the average level of thecatalyst surface in the cylinder.8.Calculation8.1 Calculate the mechanically tapped packing density asfollows:MTD5 W/V(1)where:MTD=mechanically tapped packing density,g/mL,W=mass of catalyst particles,g,andV=volume occupied by particles in measuring cylinder,mL.9.Precision and Bias39.1 Test ProgramAn interlaboratory study was conductedin which the named property was measured in two separate testmaterials in four separate laboratories.Practice E691,modifiedfor non-uniform data sets,was followed for the data reduction.Analysis details are in the research report.9.2 PrecisionPairs of test results obtained by a proceduresimilar to that described in the study are expected to differ inabsolute value by less than 2.772