1、Designation: D 5228 92 (Reapproved 2005)Standard Test Method forDetermination of Butane Working Capacity of ActivatedCarbon1This standard is issued under the fixed designation D 5228; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、 the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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
3、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 isexpress
4、ed 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 theres
5、ponsibility 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:2D 2652 Terminology Relating to Activated CarbonD
6、2854 Test Method for Apparent Density of ActivatedCarbonD 2867 Test Methods for Moisture in Activated CarbonD 3195 Practice for Rotameter CalibrationE 177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE 300 Practice for Sampling Industrial ChemicalsE 691 Practice for Conducting
7、 an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer to Terminology D 2652.4. Summary of Test Method4.1 An activated carbon bed of known volume and mass issaturated with butane vapor. The mass adsorbe
8、d 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
9、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 re
10、lative 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 i
11、s 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)
12、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 on
13、e capable of delivering butane at 0 to 500mL/min, both calibrated in accordance with Practice D 3195.6.4 Balance, capable of weighing to within 6 0.01 g.6.5 Fill DeviceThe vibration feed device used in TestMethod D 2854, Figs. 1 through 4, is preferred.1This test method is under the jurisdiction of
14、ASTM Committee D28 onActivated Carbon and is the direct responsibility of Subcommittee D28.04 on GasPhase Evaluation Tests.Current edition approved Oct. 1, 2005. Published October 2005. Originallyapproved in 1992. Last previous edition approved in 2000 as D 5228 92 (2000).2For referenced ASTM standa
15、rds, 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA
16、 19428-2959, United States.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
17、 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. Sampling8.1 For guidance in sa
18、mpling granular activated carbon,refer to Practice E 300.9. Calibration of a Sample Tube9.1 Clean and dry the sample tube to prevent any waterdroplets from adhering to the inner surface of the tube.9.2 Using distilled water, carefully fill the sample tubethrough the narrow side stem to prevent the i
19、ntroduction of anyair bubbles.9.2.1 Hold the sample tube upright while slowly introducingthe distilled water.Air bubbles have a tendency to form directlybelow the retainer plate of the tube.9.3 Clamp the filled sample tube in an upright position to aring stand and stopper the narrow side stem.9.4 Us
20、ing a pipet, carefully remove the water from thesample tube to the top of the retainer plate. Caution must betaken so no water is removed from below the retainer platecreating air bubbles that would result in a spurious calibrationof the sample tube. If this occurs, the tube must be refilled byrepea
21、ting 9.1 through 9.3.9.5 Using the buret, fill the sample tube with 16.7 6 0.05mL of water, then etch the tube at the level of the meniscus.10. Maintenance of Bath Water10.1 In order to prevent mold formation, the bath watershould be changed periodically.11. Procedure11.1 Dry an adequate sample as p
22、rescribed in Test MethodsD 2867, Section 4.11.2 Determine the apparent density in accordance withTestMethod D 2854 and record.11.3 Accurately weigh the empty, dry sample tube andstoppers to the nearest 0.01 g and record.11.4 Fill the adsorption tube with carbon to the etch mark ata rate of 0.35 to 1
23、.0 mL/s using the vibrating feeder apparatusdescribed in Test Method D 2854 with a funnel modified toaccommodate the adsorption tube. Larger particles will requirethe slower fill rate to achieve the required packing density.11.5 Weigh the filled sample tube and stoppers to the nearest0.01 g and reco
24、rd.11.5.1 The sample packing density, carbon weight/16.7,must be equal to at least 94 % of its dry apparent density if theresult of the determination is to be reproducible. Otherwise, theratio of purge air volume to sample volume will vary, and thequantity of butane purged will also vary from one de
25、termina-tion to the next. If the specified packing density is not achievedin the first attempt, the filling procedure must be repeated untilthe tube is packed to the required density. If after severalFIG. 1 Butane Working Capacity Apparatus Schematic1 Ground glass stopper, hollow, medium length, 14/
26、20, from Kontes CatalogNo. K-89100 Schwartz adsorption tube, or equivalent.2 5-mm rod, brace.3 17-mm O.D. 3 1.2 mm standard wall tubing.4 Coors perforated porcelain disk or extra coarse fritted disk, or equivalent.5 10-mm O.D. 3 1.0 mm standard wall tubing.6 Right angle stopcock, Kontes Catalog No.
27、K-84700, size 4, 10 mm O.D.stem, with Kontes Catalog No. K-89340 size B serrated hose connector, orequivalent.7 Dimension corresponding to a volume of 16.7 mL above the retainer plate.FIG. 2 Butane Working Capacity Sample TubeD 5228 92 (2005)2attempts the desired packing density cannot be achieved,
28、thepercentage should be noted and the procedure continued.11.6 Set the water bath control to maintain a temperature of25 6 0.2C.11.7 Clamp the sample tube in a vertical position in the 256 0.2C water bath and attach the tube to the output of the flowmeter. If the entire apparatus is not in a hood, a
29、ttach a shortlength of tubing from the effluent side of the sample tube to anexhaust vent.11.8 Regulate the flow to pass butane through the carbonbed at 250 6 5 mL/min. Continue the flow of butane for atleast 900 s.11.9 Turn off the butane, disconnect the tubing, and imme-diately stopper the sample
30、tube. Remove the sample tube fromthe water bath, dry the sample tube, and visually inspect thetube for any condensed water vapor. If any condensed water isobserved, stop the testing and begin the test procedure again.11.10 Weigh the filled sample tube and its stoppers to thenearest 0.01 g and record
31、.11.11 Reconnect the sample tube to the apparatus and flowbutane for an additional 600 s and weigh and record. Repeat toconstant weight.11.12 Reconnect the saturated carbon and sample tube andpurge with dry organic free air for 2400 6 20sat3006 5mL/min.11.13 Turn off the purge flow, disconnect tubin
32、g, installstoppers, remove the sample tube from the water bath, and dry.11.14 Weigh to the nearest 0.01 g and record.12. Calculation12.1 The calculations described in this section are basedupon the following determinations made during the course ofthe procedure:A = Apparent density from 11.2,B = Wei
33、ght of sample tube and stoppers,C = Weight of carbon sample, sample tube, and stoppers,D = Weight of saturated carbon, sample tube, and stoppers,andE = Weight of purged carbon, sample tube, and stoppers.NOTE 1Asample data and calculations sheet for BWC determinationsis given in Annex A1.12.2 Calcula
34、te the BWC on weight and volume bases asfollows:BWC, W/W % 5D 2 E!C 2 B!3 100 (1)BWC, W/V g/100 mL 5D 2 E!C 2 B!3 A 3 100 (2)12.3 Calculate the butane activity on weight and volumebases as follows:Butane activity, W/W % 5D 2 C!C 2 B!3 100 (3)Butane activity, W/V g/100 mL 5D 2 C!C 2 B!3 A 3 100 (4)12
35、.4 Calculate the butane retentivity on weight and volumebases as follows:Butane retentivity, W/W % 5E 2 C!C 2 B!3 100 (5)Butane retentivity, W/V g/100 mL 5E 2 C!C 2 B!3 A 3 100 (6)13. Report13.1 The analysis report shall include the following infor-mation:13.1.1 Name of activated carbon supplier,13.
36、1.2 Grade designation of the sample,13.1.3 Nominal partial size range,13.1.4 Butane working capacity,13.1.5 Butane activity,13.1.6 Butane retentivity,13.1.7 Name of the agency and technician running the test,13.1.8 Identification number and date of the test, and13.1.9 Lot number from which the sampl
37、e was taken.14. Precision and Bias14.1 An interlaboratory study of this test method wasconducted in 1990.3Each of eight laboratories tested threerandomly drawn test specimens from each of three differentactivated carbons. Practice E 691 and its computer softwarewere followed for the design of the st
38、udy and the data analysis.14.2 95 % Limit on Repeatability (within Laboratory) inPercent:Activated CarbonABCActivity %, weight/weight 1.95 2.34 .97Retentivity %, weight/weight 2.52 1.80 1.77Working capacity %, weight/weight 2.05 3.14 2.19Activity g/100 mL, weight/vol 0.68 0.70 0.40Retentivity g/100
39、mL, weight/vol 0.72 0.52 0.95Working capacity g/100 mL, weight/vol0.51 0.92 1.0414.3 95 % Limit on Reproducibility (between Laboratories)in Percent:Activated CarbonABCActivity %, weight/weight 3.57 3.15 1.05Retentivity %, weight/weight 3.75 3.79 3.79Working capacity %, weight/weight 5.06 4.70 3.83Ac
40、tivity g/100 mL, weight/vol 0.91 1.08 0.57Retentivity g/100 mL, weight/vol 1.05 1.22 1.84Working charge g/100 mL, weight/vol1.41 1.51 2.0614.4 Apparent Densitys 95 % Repeatability and Reproduc-ibility Limits:Activated CarbonABCRepeatability g/100 mL 0.012 0.004 0.008Reproducibility g/100 mL 0.019 0.
41、021 0.025NOTE 2The terms repeatability and reproducibility limit are used asspecified in Practice E 177.3Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D-28-1003.D 5228 92 (2005)3ANNEX(Mandatory Information)A1. DATA AND CALCULA
42、TIONS SHEET FOR BWC DETERMINATIONSA1.1 See Fig. A1.1:FIG. A1.1 Data and Calculations Sheet for BWC DeterminationsD 5228 92 (2005)4ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard a
43、re expressly advised that determination of the validity of any such patent rights, and the riskof infringement of 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
44、 revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which y
45、ou may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to 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 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).D 5228 92 (2005)5
