1、Designation: D 2375 05Standard Test Method forManganese in Paint Driers by EDTA Method1This standard is issued under the fixed designation D 2375; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number
2、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 a titrimetric determination ofmanganese in liquid paint driers that can be dissolved in atoluene-alcohol mixture and
3、utilizes the disodium salt ofethylenediaminetetraacetic acid dihydrate (EDTA).1.2 This test method is not applicable to drier blends.1.3 All cations that can be titrated with EDTA in alkalinemedia interfere and must not be present in the sample.1.4 The values stated in SI units are to be regarded as
4、 thestandard. The values given in parentheses are for informationonly.1.5 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
5、 applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 600 Specification for Liquid Paint DriersD 1193 Specification for Reagent WaterE 180 Practice for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial ChemicalsE 300 Practic
6、e for Sampling Industrial Chemicals3. Summary of Test Method3.1 The liquid drier is dissolved in toluene and ethyl alcoholand treated with an excess of standard EDTA solution. Theexcess is titrated with standard zinc chloride solution usingEriochrome Black-T as the indicator.4. Significance and Use4
7、.1 The amount of manganese drier used in oxidizing-typecoatings significantly affects their drying properties. This testmethod may be used to confirm the stated manganese contentof pure liquid manganese drier soluble in toluene-alcohol andmanufactured for use by the coatings industry.5. Apparatus5.1
8、 Centrifuge, capable of developing 1000 to 2000 g.6. Reagents6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Soci
9、ety,where such specifications are available.3Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.6.2 Purity of WaterUnless otherwise indicated, referencesto water shall be unders
10、tood to mean reagent water conformingto Type II of Specification D 1193.6.3 Ammonium Chloride (NH4Cl).6.4 Ammonium Hydroxide (sp gr 0.90)Concentrated am-monium hydroxide (NH4OH).6.5 l-Ascorbic Acid.6.6 Buffer SolutionAdd 350 mL of concentrated NH4-OH(sp gr 0.90) to 54 g of NH4Cl and dilute to 1 L wi
11、th water.6.7 Eriochrome Black-T IndicatorTriturate 0.2 g of Erio-chrome Black-T and 100 g of NaCl, and store the mixture in atightly stoppered bottle. This mixture remains stable for severalyears.6.8 Ethyl Alcohol (95 %), pure or denatured.6.9 EDTA, Standard Solution (0.05 M)Dissolve 18.62 gof EDTA
12、in water and dilute to 1 L. Store in a polyethylene orborosilicate glass bottle.6.10 Hydrochloric Acid (sp gr 1.19)Concentrated (hydro-chloric acid (HCl).6.11 Sodium Chloride (NaCl).6.12 Toluene.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials
13、, and Applications and is the direct responsibility ofSubcommittee D01.21 on Chemical Analysis of Paints and Paint Materials.Current edition approved Jan. 1, 2005. Published February 2005. Originallyapproved in 1965. Last previous edition approved in 1999 as D 2375 85 (1999).2For referenced ASTM sta
14、ndards, 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, AmericanChemical Societ
15、y, 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. (USPC), Rockville,MD.1C
16、opyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.13 Zinc, Granular.6.14 Zinc Chloride, Standard Solution (0.05 M)Weigh3.2690 g of zinc to the nearest 0.5 mg and dissolve in 50 mLof dilute HCl (14 mL of concentrated HCl (sp gr 1.19) to
17、 36mL of water). Warm if necessary. Dilute the zinc chloride(ZnCl2) solution to 1 L in a volumetric flask.M15 3.2690/65.37 (1)where:M1= molarity of ZnCl2solution, and65.37 = zinc to produce a 1 M solution, g.7. Sampling7.1 Take a small sample of liquid drier from bulk using theprocedures in Practice
18、 E 300 appropriate for the size of thecontainer: section on Bottle Sampling for tanks and tank cars,or section on Tube Sampling for drums and cans.NOTE 1Liquid driers are normally homogeneous so that only simplephysical tests, such as specific gravity or solids content, on top and bottomsamples from
19、 tanks, are required to confirm that separation has notoccurred. Agitate drums in accordance with section on Tube Sampling inPractice E 300.7.2 Examine the sample of drier for sediment or suspendedmatter which, if present, is evidence of noncompliance withSpecification D 600.7.3 If the sample is hom
20、ogeneous keep it in a stopperedvessel to prevent solvent evaporation prior to analysis.8. Standardization8.1 EDTA, Standard Solution (0.05 M)Measure 40.00mL of the EDTA solution into a 250-mL flask that contains 10mL of toluene and 100 mL of alcohol. Add 15 mL of buffersolution and 0.2 g of indicato
21、r mixture, and mix thoroughly.Titrate with the standard zinc chloride solution to the firstpermanent appearance of a red color.8.1.1 Calculate the molarity of the EDTA solution, M2,asfollows:M25 V1M1/40.0 (2)where:V1= ZnCl2solution, mL,40.0 = EDTA solution titrated, mL.9. Procedure9.1 Check the clar
22、ity of the drier. If not clear, centrifuge aportion of the sample until it is clear. Keep the centrifuge tubestoppered so that solvent will not evaporate.9.2 From a buret place a few grams of the drier in a 50-mLErlenmeyer flask that is fitted with a cork through which adropping tube and rubber bulb
23、 (or eye dropper) pass and obtainthe total weight. Weigh by difference two or three 1-g speci-mens (10 drops weigh about 0.2 g) to the nearest 0.5 mg into400-mL assay beakers or wide-mouthed flasks (Note 2). Add10 mL of toluene to each specimen and swirl to mix. Add 100mL of 95 % ethyl alcohol and s
24、wirl again until the specimen isdissolved and well dispersed. From a buret measure 40.0 mL ofEDTA solution into each beaker. Add 0.3 g of ascorbic acid, 15mL of buffer solution, and 0.2 g of the indicator mixture. Mixthoroughly by swirling. Titrate with the standard ZnCl2solu-tion to the first perma
25、nent tinge of red. Maintain vigorousswirling during the titration to ensure thorough mixing of thetwo phases which may appear.NOTE 2If a magnetic stirrer is available, it is convenient to titrate inan ordinary beaker. Stirring magnetically ensures thorough mixing duringthe titration.NOTE 3If the end
26、 point is overstepped, add 1.0 mL of the EDTAsolution to the mixture and titrate again with standard ZnCl2solution. Usetotal volume of each solution for the calculation.10. Calculation10.1 Calculate the percent manganese present, A, as fol-lows:A 5 V23 M2! 2 V33 M1! 3 5.494/S (3)where:V2= EDTA solut
27、ion, mL,V3= ZnCl2solution required for specimen, mL,S = specimen used, g, and5.494 = millimolar weight of manganese 3 100.11. Precision and Bias (see Practice E 180)11.1 Precision:11.1.1 RepeatabilityTwo results, each the mean of dupli-cate determinations, obtained by the same operator on differentd
28、ays should be considered suspect if they differ by more than0.05 % manganese.11.1.2 ReproducibilityTwo results, each the mean of du-plicate determinations, obtained by operators in different labo-ratories should be considered suspect if they differ by morethan 0.15 % manganese.11.2 BiasBias cannot b
29、e determined for this methodbecause there are no accepted standards for manganese in paintdriers.12. Keywords12.1 drier analysis; EDTA method; manganeseD2375052ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this stan
30、dard. 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 responsible technical committee and must be revie
31、wed 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 consideration at a meeting of theresponsibl
32、e 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 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).D2375053
