1、Designation: D6385 99 (Reapproved 2017)Standard Test Method forDetermining Acid-Extractable Content in Activated Carbonby Ashing1This standard is issued under the fixed designation D6385; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, 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 is to be used for determination of theacid-extractable content of a sample of activa
3、ted 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 requires
4、the performance ofTest Method D2866.1.2 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 add
5、ressed in Test Method D2866.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of thi
6、s standard to establish appro-priate safety and health practices and determines the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD2866 Test Method for Total Ash Content of ActivatedCarbonD2867 Test Methods for M
7、oisture in Activated CarbonE300 Practice for Sampling Industrial Chemicals3. Summary of Test Method3.1 The percent acid-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
8、 has been acid extracted.4. Significance and Use4.1 The quantitative determination of acid-extractable con-tent is useful in evaluating activated carbon samples thatcontain acid-soluble impurities. These acid-soluble impuritiescan affect applications of activated carbon.4.2 Limitations of MethodHydr
9、ochloric acid is used inthis test method as the extracting acid. All elements orcompounds present in the activated carbon 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
10、 Glass Beakers, for boiling and drying thesample.5.2 Watch Glass, suitable for 250-mL beaker.5.3 Graduated Cylinders, 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 ab
11、ove filter flask.5.7 Filter Paper, which is hardened, ashless paper, 8micron pore size and 7 cm in diameter is recommended, 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 5 C.5.9 Muffle Furnac
12、e, as specified in Test Method D2866.5.10 Porcelain Crucibles, as specified in Test MethodD2866.5.11 Desicator, containing 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 o
13、f 0.1 mg.1This test method is under the jurisdiction of ASTM Committee D28 on LiquidPhase Evaluation.Current edition approved March 1, 2017. Published March 2017. Originallyapproved in 1999. Last previous edition approved in 2011 as D6385 99 (2011).DOI: 10.1520/D6385-99R17.2For referenced ASTM stand
14、ards, 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
15、 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization T
16、echnical Barriers to Trade (TBT) Committee.113 5.13 Carbon Particle Size Reduction, a mortar and pestle, orany other means of systematically reducing activated carbonparticle size to pass through a No. 325 U.S. mesh screen. Thesize reduction device must be constructed of material that willnot contam
17、inate 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 Hydrochloric Acid, ACS reagent grade isrecommended, 37 % HC1 w/w 6 2%.6.2 ASTM Type II Water, or better is recommended for lowresidue content. Whe
18、never 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 tested in accordance with Practice E300.Samples should be uniformly dried to a constant weight beforeproceeding with this test method. If dryi
19、ng is not possible, thenpercent moisture should be determined by Test Methods D2867and the appropriate correction to the sample weight should bemade.8. Procedure8.1 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
20、.S. mesh screen. Retain all the sample forthe test.8.2 Determine the total ash content of this sample by TestMethod D2866.8.3 Weigh out to the nearest 0.1 mg sufficient 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.
21、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 hydrochloric acid. Swirlbeaker to wet sample thoroughly.8.6 Place the beaker and contents on a hot plate and bring toa boil, maintaining boiling for
22、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 allow tocool.8.8 Vacuum filter the mixture through the 7-cm filter funnelwith hardened filter paper in place. Wash the carbon retainedon the
23、filter paper with several portions of water to thoroughlyremove all acid residue. Discard filtrate unless analysis ofacid-soluble components in this extract is desired.8.9 Transfer the filter, filter paper and carbon together intoan oven and dry for 30 min at 150 C. This process permitseasy separati
24、on 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 dried, acid-extractedcarbon, using the mass of the carbon sample from 8.3. Using asuitable muffle furnace at 650 C, thoroughly ash the carbona
25、nd paper as described in Test Method D2866.9. Calculation of Result9.1 The acid-extractable content as previously defined iscalculated as follows (correction for water content is necessaryif the sample was not dried before ashing):Acid Extractable Content %! 5 A 2 B! (1)where:A = percent total ash c
26、ontent of activated carbon sample asdetermined by Test Method D2866, andB = percent total ash content of acid-extracted sample, alsoas determined by Test Method D2866.10. Precision and Bias10.1 Based on limited information from one laboratory, therepeatability standard deviation and 95 % repeatabili
27、ty 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 total ash content of the original sample. The precisionand repeatability of Test Method D2866 also is a factor in therepeatability of this t
28、est method.11. Keywords11.1 acid; acid extractable; activated carbon; ashASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity o
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