ASTM_D_5158_-_98_2013.pdf

Designation:D515898(Reapproved 2013)Standard Test Method forDetermination of Particle Size of Powdered ActivatedCarbon by Air Jet Sieving1This standard is issued under the fixed designation D5158;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 particlesize of powdered activated carbons using an air-jet sievedevice.For purposes of this test method,powdered activatedcarbon is defined as activated carbon in particle sizes predomi-nantly smaller than 80 mesh.1.2 The values stated in SI units are to be regarded as thestandard.The inch-pound units given in parentheses are forinformation only.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:2D2652 Terminology Relating to Activated CarbonE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE300 Practice for Sampling Industrial ChemicalsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Definitions Terms relating to this test method aredefined in Terminology D2652.4.Summary of Test Method4.1 A weighed sample of as-received powdered activatedcarbon is placed in a test sieve that is inserted in the sieveholder of the air-jet sieve assembly.Air is passed through thesieve from a slowly-rotating nozzle to fluidize the sample for agiven period of time.Exit air flow removes undersized par-ticles downward through the test sieve to a collection canister.The amount of carbon retained on the test sieve is weighed andthe percent passing the test sieve is computed by difference.For a particle size distribution,the test must be repeated usingsieves with different openings.5.Significance and Use5.1 The particle size of powdered activated carbon issometimes used to evaluate filter cake filtration rates and thefilter penetration in filtering applications.The selection andhandling of powdered activated carbon,and operation ofprocesses using powdered activated carbon,requires theknowledge of the particle size.NOTE1Relative humidity(RH)can affect the repeatability andaccuracy of this test.Activated carbon not at equilibrium with the RH ofthe ambient air may lose or gain weight accordingly,dependent uponwhether or not the carbon picks up or loses moisture.6.Apparatus6.1 Air-Jet Sieve Assembly.6.2 Wire Cloth Sieves,bronze or stainless steel(stainlesssteel sieves preferred),200 and 325 mesh,in accordance withSpecification E11.The sieves shall be 203 mm(8 in.)indiameter.6.3 Brush,soft bristle.6.4 Balance,with a sensitivity of 1.0 mg.6.5 Ultrasonic Bath,capable of cleaning 203-mm(8-in.)diameter sieves.7.Sampling7.1 Activated carbon is not strictly a chemically and physi-cally homogeneous material.To enable performing meaningfultests within the stated tolerances of the ASTM test methods,itis essential that sampling be performed to obtain as represen-tative a sample as possible.When a small amount of samplerepresents tons of material,the collection,mixing,and prepa-ration of samples is extremely important.The practice de-scribed in Practice E300 is suitable to ensure that sampling and1This test method is under the jurisdiction of ASTM Committee D28 onActivated Carbon and is the direct responsibility of Subcommittee D28.02 on LiquidPhase Evaluation.Current edition approved Nov.1,2013.Published December 2013.Originallyapproved in 1991.Last previous edition approved in 2005 as D5158 98(2005).OI:10.1520/D5158-98R13.2For 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 sample preparation of activated carbon is appropriate for theperformance of this test method.In absence of followingPractice E300,a detailed specific sampling and sample prepa-ration procedure,suitable to the parties involved,needs to beprepared.8.Procedure8.1 Determine the size of the test sample in accordance withASTM STP 447B.3In deciding on the size of a test sample,consideration must be given to the character of the material,itsscreenability,and the range of particle sizes present.8.2 Weigh the established weight of a representative sampleof powdered activated carbon,which has been taken andprepared in strict accordance with Practic