1、Designation: D 6385 99 (Reapproved 2006)Standard Test Method forDetermining Acid Extractable Content in Activated Carbonby Ashing1This standard is issued under the fixed designation D 6385; the number immediately following the designation indicates the year oforiginal adoption or, in the case of rev
2、ision, 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 is to be used for determination of theacid extractable content of a sample of act
3、ivated carbon. Thistest method presupposes the existence of substances other thancarbon to be present with activated carbon but does not purportto address or identify those substances which may be present.This test method should be applicable to any form in whichactivated carbon may exist and requir
4、es the performance ofTest Method D 2866.1.2 This test method requires the use of concentratedhydrochloric acid, which should be used in an appropriate andsafe manner, with eye protection, skin protection and handlingcarried out in a properly operating fume hood. The proper useof a muffle furnace is
5、addressed in Test Method D 2866.1.3 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 determines the applica-bility of regulatory limitat
6、ions prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reagent WaterD 2866 Test Method for Total Ash Content of ActivatedCarbonD 2867 Test Methods for Moisture in Activated CarbonE 300 Practice for Sampling Industrial Chemicals3. Summary of Test Method3.1 The percent a
7、cid extractable content of an activatedcarbon sample is determined by the difference between thepercent mass of total ash of a sample and the percent mass oftotal ash of a sample which has been acid extracted.4. Significance and Use4.1 The quantitative determination of acid extractable con-tent is u
8、seful in evaluating activated carbon samples thatcontain acid soluble impurities. These acid soluble impuritiescan affect applications of activated carbon.4.2 Limitations of MethodHydrochloric acid is used inthis test method as the extracting acid. All elements orcompounds present in the activated c
9、arbon sample, which canbe acid extracted, are assumed to form water soluble chloridesalts. Hydrochloric acid may not solubilize all impurities ofactivated carbon.5. Apparatus5.1 250-mL Glass Beakers, for boiling and drying thesample.5.2 Watch Glass, suitable for 250-mL beaker.5.3 Graduated Cylinders
10、, of 100-mL (TD) and 25-mL (TD)size.5.4 Buchner Vacuum Funnel, 7-cm ID or equivalent filteringdevice.5.5 Vacuum Filter Flask, with side arm, 500 mL.5.6 Vacuum Filter Collar, for the above filter flask.5.7 Filter Paper, which is hardened, ashless paper, # 8micron pore size and 7 cm in diameter is rec
11、ommended, or adiameter which matches the vacuum funnel. The paper will beashed with the carbon, so ashless paper is necessary.5.8 Drying Oven, maintained at 150 C 6 5C.5.9 Muffle Furnace, as specified in Test Method D 2866.5.10 Porcelain Crucibles, as specified in Test MethodD 2866.5.11 Desicator, c
12、ontaining indicating silica gel or any otherdesicant, which is effective in maintaining dryness of coolinghot crucibles or oven dried carbon samples.5.12 Balance, capable of measurement of 0.1 mg.5.13 Carbon Particle Size Reduction, a mortar and pestle, orany other means of systematically reducing a
13、ctivated carbonparticle size to pass through a No. 325 U.S. mesh screen. The1This test method is under the jurisdiction of ASTM Committee D28 on LiquidPhase Evaluation.Current edition approved Oct. 1, 2006. Published November 2006. Originallyapproved in 1999. Last previous edition approved in 1999 a
14、s D 6385 99.2For 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.1Copyright ASTM International, 100 Barr Harbor Dr
15、ive, PO Box C700, West Conshohocken, PA 19428-2959, United States.size reduction device must be constructed of material that willnot contaminate the carbon sample with acid soluble materials.5.14 No. 325 U.S. Mesh Screen, for sieving the sample aftersize reduction.6. Reagents6.1 Concentrated Hydroch
16、loric Acid, ACS reagent grade isrecommended, 37 % HC1 w/w 6 2%.6.2 ASTM Type II water, or better is recommended for lowresidue content. Whenever water is used in this test method,Type II or better is implied.7. Test Sample7.1 A test sample or samples should be representative of thematerial being tes
17、ted in accordance with Practice E 300.Samples should be uniformly dried to a constant weight beforeproceeding with this test method. If drying is not possible, thenpercent moisture should be determined by Test Method D 2867and the appropriate correction to the sample weight should bemade.8. Procedur
18、e8.1 A representative sample or samples should be ground ormilled so that 95 % or more of the sampled mass will be passedthrough a No. 325 U.S. mesh screen. Retain all the sample forthe test.8.2 Determine the total ash content of this sample by TestMethod D 2866.8.3 Weigh out to the nearest 0.1 mg s
19、ufficient dried acti-vated carbon so that the estimated amount of ash will be at least0.1 g.8.4 Quantitatively transfer to a 250-mL beaker.8.5 Add reagents to the carbon in the beaker in the follow-ing order: slowly add 100 mL (6 1 mL) of water, then slowlyadd 25 mL (6 1 mL) of concentrated hydrochl
20、oric acid. Swirlbeaker to wet sample thoroughly.8.6 Place the beaker and contents on a hot plate and bring toa boil, maintaining boiling for at least 5 min. A watch glassshould be used to cover the beaker while boiling the carbon-acid-water mixture.8.7 After boiling, remove the beaker from heat and
21、allow tocool.8.8 Vacuum filter the mixture through the 7-cm filter funnelwith hardened filter paper in place. Wash the carbon retainedon the filter paper with several portions of water to thoroughlyremove all acid residue. Discard filtrate unless analysis of acidsoluble components in this extract is
22、 desired.8.9 Transfer the filter, filter paper and carbon together intoan oven and dry for 30 min at 150C. This process permits easyseparation of the paper and carbon from the Buchner filter.8.10 Quantitatively transfer the paper and carbon to a taredcrucible.8.11 Determine the ash content of the dr
23、ied, acid extractedcarbon, using the mass of the carbon sample from 8.3. Using asuitable muffle furnace at 650C, thoroughly ash the carbonand paper as described in Test Method D 2866.9. Calculation of Result9.1 The acid extractable content as previously defined iscalculated as follows (correction fo
24、r water content is necessaryif the sample was not dried before ashing):Acid Extractable Content %!5 A 2 B! (1)where:A = Percent total ash content of activated carbon sample asdetermined by Test Method D 2866.B = Percent total ash content of acid extracted sample, alsoas determined by Test Method D 2
25、866.10. Precision and Bias10.1 Based on limited information from one laboratory, therepeatability standard deviation and 95 % repeatability limitsare as follows:Repeatability Standard Deviation: 9.3 % (2)95 % Repeatability Limits: 0.90 (3)10.2 The percent acid soluble ash is dependent on thepercent
26、total ash content of the original sample. The precisionand repeatability of Test Method D 2866 also is a factor in therepeatability of this test method.11. Keywords11.1 acid; acid extractable; activated carbon; ashASTM International takes no position respecting the validity of any patent rights asse
27、rted in connection with any item mentionedin this standard. Users of this standard are 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
28、 the responsible technical committee and must be reviewed every five years andif not 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 recei
29、ve careful consideration at a meeting of theresponsible technical committee, which you 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 Inter
30、national, 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 6385 99 (2006)2
