1、Designation: D1767 89 (Reapproved 2017)Standard Test Method forEthylene Diamine Tetraacetate (EDTA) in Soaps or SyntheticDetergents1This standard is issued under the fixed designation D1767; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, 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 ethylenediamine tetraacetate (EDTA) in soaps and synt
3、hetic detergents.Throughout this test method EDTA represents the hydrateddisodium salt containing 2 moles of H2O. In the chemicalliterature this is frequently abbreviated to Na2H2Y42H2O.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thi
4、sstandard.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. Mate
5、rial SafetyData Sheets are available for reagents and materials. Reviewthem for hazards prior to usage.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent Water3. Purity of Reagents3.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indica
6、ted, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to perm
7、it its use without lessening theaccuracy of the determination.3.2 Unless otherwise indicated, references to water shall beunderstood to mean reagent water conforming to SpecificationD1193.4. Reagents4.1 Copper Sulfate Solution (1 mL = 0.0037 g EDTA diso-dium salt)Dissolve 2.497 g of copper sulfate (
8、CuSO45H2O)in water and dilute to 1 L. The actual EDTA equivalent shouldbe determined by the titration of a known weight of EDTAdisodium salt.4.2 PAN Indicator SolutionDissolve 0.1 g of 1-(2pyridylazo)-2-naphathol4in 100 mL of methyl alcohol.5. Procedure5.1 Weigh to the nearest 0.001ga3to5-gportion o
9、f thesample estimated to contain 1 % of EDTA disodium salt. Varythe amount of the sample used depending upon the actualamount of EDTA present. Weigh into a 250-mL beaker, diluteto approximately 75 mL with water, and adjust the pH toapproximately 5.0 by the addition of acetic acid (Note 1). Add4 drop
10、s of the PAN indicator solution. Titrate the sample withCuSO4solution to a transition in color from yellow to red.NOTE 1Removal of soap fatty acids by filtration through a wet filterpaper prior to titration will sharpen the end point.6. Calculation6.1 Calculate the percentage of EDTA disodium salt i
11、n thesample as follows:EDTA, weight % 5 AB/C! 3100 (1)where:A = millilitres of CuSO4solution required for titration of thesample,B = grams of EDTA disodium salt equivalent to 1 mL of theCuSO4solution, and1This test method is under the jurisdiction of ASTM Committee D12 on Soapsand Other Detergents a
12、nd is the direct responsibility of D12.12 on Analysis andSpecifications of Soaps, Synthetics, Detergents and their Components.Current edition approved Jan. 1, 2017. Published February 2017. Originallyapproved in 1960. Last previous edition approved in 2009 as D1767 89 (2009).DOI: 10.1520/D1767-89R17
13、.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.3Reagent Chemicals, American Chemical Society Specifications
14、, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc
15、. (USPC), Rockville,MD.4Eastman Organic Chemical No. 7192 has been found satisfactory for thispurpose.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recogniz
16、ed principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1C = grams of sample used.7. Precision and Bias7.1 The following cri
17、teria should be used for judging theacceptability of results (95 % probability):7.1.1 Liquid SoapDuplicate results by the same operatorshould not be considered suspect unless they differ by morethan 60.01 %. The overall reproducibility is 60.03 %.7.1.2 Synthetic DetergentsDuplicate results by the sa
18、meoperator should not be considered suspect unless they differ bymore than 60.01 %. The overall reproducibility is 60.02 %.8. Keywords8.1 copper sulfate titration; EDTA; ethylene diamine tet-raacetateASTM International takes no position respecting the validity of any patent rights asserted in connec
19、tion 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 the responsib
20、le 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 receive careful con
21、sideration 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 International, 100
22、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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 89 (2017)2
