Ally Designation: D 5228— 92 (Reapproved 2005)
`
`“ud
`INTERNATIONAL
`
`Standard Test Method for
`Determination of Butane Working Capacity of Activated
`Carbon’
`
`This standard is issued under the fixed designation D 5228; the number immediately following the designation indicates the year of
`original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
`superscript epsilon (€)
`indicates an editorial change since the last revision or reapproval.
`
`1. Scope
`1.1 This test method covers the determination of the butane
`working capacity (BWC) of new granular activated carbon.
`The BWC is defined as the difference between the butane
`adsorbed at saturation and the butane retained per unit volume
`of carbon after a specified purge. The test method also
`produces a butane activity valuc that is defined as the total
`amount of butane adsorbed on the carbon sample and is
`expressed as a mass of butane per unit weight or volume of
`carbon.
`
`1.2 The values stated in SI units are to be regarded as
`standard. No other units of measurement are included in this
`standard.
`
`1.3 This standard does not purport to address all of the
`safety concerns,
`if any, associated with its use. It
`is the
`responsibility 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 specific
`hazard statement, see 7.1.
`
`2. Referenced Documents
`
`2.1 ASTM Standards: *
`D 2652 Terminology Relating to Activated Carbon
`D 2884 Test Method for Apparent Density of Activated
`Carbon
`D 2867 Test Methods for Moisture in Activated Carbon
`D 3195 Practice for Rotameter Calibration
`i 177 Practice for Use of the Terms Precision and Bias in
`ASTM Test Methods
`E 300 Practice for Sampling Industrial Chemicals
`E691 Practice for Conducting an Interlaboratory Study to
`Determine the Precision of a Test Method
`
`' This test method is under the jurisdiction of ASTM Committee D28 on
`Activated Carbon and is the direct responsibility of Subcommittee D28.04 on Gas
`Phase Evaluation Tests.
`Current edition approved Oct. 1, 2005. Published October 2005. Originally
`approved in 1992. Last previous edition approved in 2000 as D 5228 — 92 (2000).
`° For referenced ASTMstandards, visit the ASTM website, www.astm.org, or
`contact AS'TM Customer Service at service@astm.org. Hor Annual Book of ASTM
`Standards volume information,refer to the standard’s Document Summary page on
`the ASTM website.
`
`3. Terminology
`3.1 Definitions—For definitions of terms used in this test
`method, refer to Terminology 1D 2652.
`
`4. Summaryof Test Method
`4.1 An activated carbon bed of known volume and massis
`saturated with butane vapor. The mass adsorbed at saturation is
`noted. The carbon bed is then purged under prescribed condi-
`tions with dry hydrocarbon free air. The loss of mass is the
`BWCand is expressed as mass of butane per unit volume of
`carbon.
`
`5. Significance and Use
`is a
`5.1 The BWC, as determined by this test method,
`measure of the ability of an activated carbon to adsorb and
`desorb butane from dry air under specified conditions. It is
`useful for quality control and evaluation of granular activated
`carbons that are used in applications where the adsorption of
`butane and desorption with dry air are of interest. The BWC
`can also provide a relative measure of the effectiveness of the
`tested activated carbons on other adsorbates.
`5.2 The butane activity and retentivity can also be deter-
`mined underthe conditions of the test. The butane activity is an
`indication of the micropore volume of the activated carbon
`sample. The butane retentivity is an indication of the pore
`structure of the activated carbon sample.
`
`6. Apparatus
`6.1 Water Bath, capable of maintaining a temperature of 25°
`* 0.2°C and of sufficient depth so the entire carbon bed in the
`sample tube is immersed in the water. A 6-mm OD copper tube
`with an immersed length of 1.9 m (Fig. 1) provides adequate
`heat transfer for gas temperature control.
`6.2 Sample Tube, as shown in Fig. 2. The glass plate with
`holes is preferred to a fritted disk to support the carbon, since
`fritted disks can vary widely in pressure drop.
`6.3 Flow Meters, one capable of delivering air at 0 to 500
`mL/min, and one capable of delivering butane at 0 to 500
`mL/min, both calibrated in accordance with Practice D 3195.
`64 Balance, capable of weighing to within + 0.01 ¢g.
`6.5 Fill Device—The vibration feed device used in Test
`Method D 2854, Figs.
`| through 4, is preferred.
`
`Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
`
`Copyright by ASTM Int'l (all rights reserved);
`Reproduction authorized per License Agreement with ERIKA ROYVAL (DELPHI CORPORATION); Tue Nov 8 11:51:40 EST 2005
`
`BASF-1024
`U.S. Patent No. RE38,844
`
`BASF-1024
`U.S. Patent No. RE38,844
`
`

`

`ADSORPTION TUBE
`
`TO VENT
`
`Ally p 5228 - 92 (2005)
`0.S°C. Its specific gravity is 2.046 relative to air. Butane may
`be narcotic in high concentrations and is considered a simple
`asphyxiant. If the entire apparatus is not set up in a fume hood,
`provision must be made to vent
`the gas coming from the
`discharge stem of the sample tube.)
`7.2. Dry Air, free of organics, with a dew point no higher
`than —32°C.
`
`TWO-WAY STOP COCK {|
`
`GAS HEAT
`EXCHANGE
`com
`1.9M LONG
`
`3
`
`¢
`
`8. Sampling
`8.1 For guidance in sampling granular activated carbon,
`refer to Practice F 300.
`
`9. Calibration of a Sample Tube
`9.1 Clean and dry the sample tube to prevent any water
`droplets from adhering to the inner surface of the tube.
`9.2 Using distilled water, carefully fill
`the sample tube
`through the narrow side stem to prevent the introduction of any
`air bubbles.
`
`9.2.1 Hold the sample tube upright while slowly introducing
`the distilled water. Air bubbles have a tendency to form directly
`below the retainer plate of the tube.
`9.3 Clamp the filled sample tube in an upright position to a
`ring stand and stopper the narrow side stem.
`9.4 Using a pipet, carefully remove the water from the
`sample tube to the top of the retainer plate. Caution must be
`taken so no water is removed from below the retainer plate
`creating air bubbles that would result in a spurious calibration
`of the sample tube. If this occurs, the tube mustbe refilled by
`repeating 9.1 through 9.3.
`9.5 Using the buret, fill the sample tube with 16.7 + 0.05
`mL of water, then etch the tube at the level of the meniscus.
`
`10. Maintenance of Bath Water
`
`10.1 In order to prevent mold formation,
`should be changed periodically.
`
`the bath water
`
`11. Procedure
`
`11.1 Dry an adequate sample as prescribed in Test Methods
`D 2867, Section 4.
`11.2 Determine the apparent density in accordance with Test
`Method D 2854 and record.
`11.3 Accurately weigh the empty, dry sample tube and
`stoppers to the nearest 0.01 g and record.
`11.4 Fill the adsorption tube with carbonto the etch mark at
`arate of 0.35 to 1.0 mL/s using the vibrating feeder apparatus
`described in Test Method D 2854 with a funnel modified to
`accommodate the adsorption tube. Largerparticles will require
`the slower fill rate to achieve the required packing density.
`11.5 Weigh the filled sample tube and stoppers to the nearest
`0.01 g and record.
`11.5.1 The sample packing density, carbon weight/16.7,
`must be equal to at least 94 % of its dry apparent density if the
`result of the determination is to be reproducible. Otherwise, the
`ratio of purge air volume to sarmple volume will vary, and the
`quantity of butane purged will also vary from one determina-
`tion to the next. If the specified packing density is not achieved
`in the first attempt, the filling procedure must be repeated until
`the tube is packed to the required density. If after several
`
`N-BUTANE
`
`FLOW METER
`
`ORGANIC FREE
`DRY AIR
`
`:
`
`CONSTANT TEMPERATURE BATH
`
`FLOW METER
`
`FIG. 1 Butane Working Capacity Apparatus Schematic
`
`4D 1351
`
`
`
`
` +S
`
`
`
`
`40mm
`REF
`
`REF
`
`1- Ground glass stopper, hollow, medium length, 14/20, from Kontes Catalog
`No. K-89100 Schwartz adsorption tube, or equivalent.
`2— 5-mim rod, brace.
`3 17-mm O.D. x 1.2 mm standard wall tubing.
`4— Coor’s perforated porcelain disk or extra coarse fritted disk, or equivalent.
`5- 10-mm 0.D. x 1.0 mm standard wall tubing.
`6- Right angle stopcock, Kontes Catalog No. K-84700, size 4, 10 mm OD.
`stem, with Kontes Catalog No. K-89340 size B serrated hose connector, or
`equivalent.
`7-— Dimension corresponding to a volume of 16.7 mL above the retainerplate.
`FIG. 2 Butane Working Capacity Sample Tube
`
`6.6 Buret, Class A, 25 mL capacity.
`6.7 Apparatus Assembly shown in Fig. 1.
`
`7. Reagents
`7,1 n-Butane, C. P. Grade. (Warning—Butane is a flam-
`mable gas with a flash point of -138°C and a boiling point of
`
`Copyright by ASTM Int'l (all rights reserved);
`Reproduction authorized per License Agreement with ERIKA ROYVAL (DELPHI CORPORATION); Tue Nov 8 11:51:40 EST 2005
`
`

`

`fly p 5228 - 92 (2005)
`ait’
`
`attempts the desired packing density cannot be achieved, the
`percentage should be noted and the procedure continued.
`11.6 Set the water bath control to maintain a temperature of
`25 © 0.2°C.
`11.7 Clamp the sample tube in a vertical position in the 25
`+ 0.2°C water bath and attach the tube to the output of the flow
`meter. If the entire apparatus is not in a hood, attach a short
`length of tubing from the effluent side of the sample tube to an
`exhaust vent.
`11.8 Regulate the flow to pass butane through the carbon
`bed at 250 = 5 mL/min. Continue the flow of butane for at
`least 900 s.
`11.9 Turn off the butane, disconnect the tubing, and imme-
`diately stopper the sample tube. Remove the sample tube from
`the water bath, dry the sample tube, and visually inspect the
`tube for any condensed water vapor. If any condensed water is
`observed, stop the testing and begin the test procedure again.
`11.10 Weigh the filled sample tube and its stoppers to the
`nearest 0.01 g and record.
`11.11 Reconnect the sample tube to the apparatus and flow
`butane for an additional 600 s and weigh and record. Repeat to
`constant weight.
`11.12 Reconnect the saturated carbon and sample tube and
`purge with dry organic free air for 2400 = 20s at 300 + 5
`mL/min.
`install
`11.13 Turn off the purge flow, disconnect tubing,
`stoppers, remove the sample tube from the water bath, and dry.
`11.14 Weigh to the nearest 0.01 g and record.
`12. Calculation
`
`12.1 The calculations described in this section are based
`upon the following determinations made during the course of
`the procedure:
`
`Dakes i
`
`bry
`
`= Apparent density from 11.2,
`Weight of sample tube and stoppers,
`Weight of carbon sample, sample tube, and stoppers,
`= Weight of saturated carbon, sample tube, and stoppers,
`and
`= Weight of purged carbon, sample tube, and stoppers.
`
`Nore 1—Asample data and calculations sheet for BWC determinations
`is given in Annex Al.
`12.2 Calculate the BWC on weight and volume bases as
`follows:
`
`awe. ww @ = Oo x. 100
`: 0 (Cc — B)
`
`(D- E)
`Q2)
`BWC, W/V 9/100 mL = 7@—py X A X 100
`12.3 Calculate the butane activity on weight and volume
`bases as follows:
`
`1
`qd)
`
`oh = (D ~ C)
`.
`Butane activity, W/W % = (-B) x 100
`
`D-C)
`ws
`(4)
`Butane activity, W/V ¢/100 mL = (CB) x A X 100
`12.4 Calculate the butane retentivity on weight and volume
`bases as follows:
`
`3
`GB)
`
`tentivit wrw % = E=© x 100
`Buta
`utane retentivity,
`to = EB
`Butaneretentivity, W/V ¢/100 mL = enw x AX 100
`
`x
`
`(3)
`(
`(6)
`
`13. Report
`
`13.1 The analysis report shall include the following infor-
`mation:
`13.1.1 Name of activated carbon supplicr,
`13.1.2 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, and
`13.1.9 Lot number from which the sample was taken.
`
`14. Precision and Bias
`
`14.1 An interlaboratory study of this test method was
`conducted in 1990.2 Each of eight laboratories tested three
`randomly drawn test specimens from each of three different
`activated carbons. Practice E691 and its computer software
`were followed for the design of the study and the data analysis.
`14.2 95 % Limit on Repeatability (within Laboratory) in
`Percent:
`
`Activity %, weight/weight
`Retentivity %, weight/weight
`Working capacity %, weight/weight
`Activity g/100 mL, weight/vol
`Retentivity g/100 mL, weight/vol
`Working capacity g/100 mL, weight/
`vol
`
`Activated Carbon
`B
`
`Cc
`
`A
`
`1.95
`2.52
`2.05
`0.68
`0.72
`0.51
`
`2.34
`1.80
`3.14
`0.70
`0.52
`0.92
`
`27
`177
`2.19
`0.40
`0.95
`1.04
`
`14.3 95 % Limit on Reproducibility (between Laboratories)
`in Percent:
`
`Activity %, weight/weight
`Retentivity %, weight/weight
`Working capacity %, weight/weight
`Activity g/100 mL, weight/vol
`Retentivity g/100 mL, weight/vol
`Working charge 9/100 mL, weight’
`vol
`
`Activated Carbon
`B
`
`Cc
`
`A
`
`3.57
`3.75
`5.06
`0.91
`1.05
`141
`
`3.15
`3.79
`4.70
`1.08
`1.22
`1.51
`
`1.05
`3.79
`3.83
`0.57
`1.84
`2.06
`
`14.4 Apparent Density’s 95 % Repeatability and Reproduc-
`ibility Limits:
`
`Repeatability g/100 mL
`Reproducibility g/100 mL
`
`A
`
`0.012
`0.019
`
`Activated Carbon
`B
`
`Cc
`
`0.004
`0.021
`
`0.008
`0.025
`
`Note 2—The terms repeatability and reproducibility limit are used as
`specified in Practice E 177.
`
`? Supporting data have been filed at ASTM International Headquarters and may
`be obtained by requesting Research Report RR: D-28-1003.
`
`Copyright by ASTM Int'l (all rights reserved);
`Reproduction authorized per License Agreement with ERIKA ROYVAL (DELPHI CORPORATION); Tue Nov 8 11:51:40 EST 2005
`
`

`

`Ally p 5228 - 92 (2005)
`
`ANNEX
`
`(Mandatory Information)
`
`Al. DATA AND CALCULATIONS SHEET FOR BWC DETERMINATIONS
`
`Al.l See Fig. Al.1:
`
`Laboratory;
`Test Performed By:____S CCCate:
`Sample Description:
`A Sample AD
`B Weight of sample tube and stoppers
`C Weight of carbon sample, tube, and stoppers
`D Weight of saturated carbon, tube, and stoppers
`E Weight of purged carbon, tube, and stoppers
`Butane working capacity W/W %
`Butane working capacity W/V g/100 mL
`Butaneactivity W/W %
`Butane activity W/V g/100 mL
`Butaneretentivity W/W %
`
`Butaneretentivity W/V 9/100 mL
`FIG. A1.1 Data and Calculations Sheet for BWC Determinations
`
`Copyright by ASTM Int'l (all rights reserved);
`Reproduction authorized per License Agreement with ERIKA ROYVAL (DELPHI CORPORATION); Tue Nov 8 11:51:40 EST 2005
`
`4
`
`

`

`Ally p 5228 - 92 (2005)
`
`ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned
`in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk
`ofinfringement of such rights, are entirely their own responsibility.
`
`This standard is subject to revision at any time by the responsible technical commitiee and must be reviewed every five years and
`if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards
`and should be addressed to ASTMInternational Headquarters. Your comments will receive careful consideration at a meeting of the
`responsible technical cormmittee, which you may attend. if you feel that your comments have not received a fair hearing you should
`make 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 above
`address or at 610-832-9585 (phone), 610-832-9555 (fax), or service@astm.org (e-mail); or through the ASTM website
`(wwwastm.org).
`
`Copyright by ASTM Int'l (all rights reserved);
`Reproduction authorized per License Agreement with ERIKA ROYVAL (DELPHI CORPORATION); Tue Nov 8 11:51:40 EST 2005
`
`§
`
`