ASTM_D_5228_-_92_2015.pdf

Designation:D522892(Reapproved 2015)Standard Test Method forDetermination of Butane Working Capacity of ActivatedCarbon1This standard is issued under the fixed designation D5228;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 butaneworking capacity(BWC)of new granular activated carbon.The BWC is defined as the difference between the butaneadsorbed at saturation and the butane retained per unit volumeof carbon after a specified purge.The test method alsoproduces a butane activity value that is defined as the totalamount of butane adsorbed on the carbon sample and isexpressed as a mass of butane per unit weight or volume ofcarbon.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.For a specifichazard statement,see 7.1.2.Referenced Documents2.1 ASTM Standards:2D2652 Terminology Relating to Activated CarbonD2854 Test Method for Apparent Density of ActivatedCarbonD2867 Test Methods for Moisture in Activated CarbonD3195 Practice for Rotameter CalibrationE177 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 For definitions of terms used in this testmethod,refer to Terminology D2652.4.Summary of Test Method4.1 An activated carbon bed of known volume and mass issaturated with butane vapor.The mass adsorbed at saturation isnoted.The carbon bed is then purged under prescribed condi-tions with dry hydrocarbon free air.The loss of mass is theBWC and is expressed as mass of butane per unit volume ofcarbon.5.Significance and Use5.1 The BWC,as determined by this test method,is ameasure of the ability of an activated carbon to adsorb anddesorb butane from dry air under specified conditions.It isuseful for quality control and evaluation of granular activatedcarbons that are used in applications where the adsorption ofbutane and desorption with dry air are of interest.The BWCcan also provide a relative measure of the effectiveness of thetested activated carbons on other adsorbates.5.2 The butane activity and retentivity can also be deter-mined under the conditions of the test.The butane activity is anindication of the micropore volume of the activated carbonsample.The butane retentivity is an indication of the porestructure of the activated carbon sample.6.Apparatus6.1 Water Bath,capable of maintaining a temperature of 256 0.2C and of sufficient depth so the entire carbon bed in thesample tube is immersed in the water.A 6-mm OD copper tubewith an immersed length of 1.9 m(Fig.1)provides adequateheat transfer for gas temperature control.6.2 Sample Tube,as shown in Fig.2.The glass plate withholes is preferred to a fritted disk to support the carbon,sincefritted disks can vary widely in pressure drop.6.3 Flow Meters,one capable of delivering air at 0 to 500mL/min,and one capable of delivering butane at 0 to 500mL/min,both calibrated in accordance with Practice D3195.6.4 Balance,capable of weighing to within 60.01 g.1This test method is under the jurisdiction of ASTM Committee D28 onActivated Carbon and is the direct responsibility of Subcommittee D28.04 on GasPhase Evaluation Tests.Current edition approved Oct.1,2015.Published October 2015.Originallyapproved in 1992.Last previous edition approved in 2010 as D5228 92(2010).DOI:10.1520/D5228-92R15.2For 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 6.5 Fill DeviceThe vibration feed device used in TestMethod D2854,Figs.1 through 4,is preferred.6.6 Buret,Class A,25 mL capacity.6.7 Apparatus Assembly shown in Fig.1.7.Reagents7.1 n-Butane,C.P.Grade.(WarningButane is a flam-mable gas with a flash point of 138C and a boiling point of0.5C.Its specific gravity is 2.046 relative to air.Butane maybe narcotic in high concentrations and is considered a simpleasphyxiant.If the entire apparatus is not set up in a fume hood,provision must be made to vent the gas coming from thedischarge stem of the sample tube.)7.2 Dry Air,free of organics,with a dew point no higherthan 32C.8.