1、Designation: D3049 89 (Reapproved 2016)Standard Test Method forSynthetic Anionic Ingredient by Cationic Titration1This standard is issued under the fixed designation D3049; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f 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 the amountof synthetic anionic ingredient in a surfactant by direct tit
3、rationwith a standardized cationic reagent. The test method is asimple and convenient means for the quantitative estimation ofthe anionic material. The end point is detected by the transferof a colored complex from an organic solvent phase to anaqueous phase. The colored complex is formed by the add
4、itionof a solution of dye to a solution of the anionic surfactant. Thiscomplex is soluble in the organic-solvent phase and insolublein the aqueous phase. When this solution is titrated with astandardized solution of a cationic reagent, the dye is displacedfrom the colored complex and, being water-so
5、luble, migrates tothe aqueous phase. Therefore, a cationic titrating solution thathas been standardized against a characterized anionic agent canbe used to analyze for other anionics of known molecular mass.1.2 This test method is applicable to alkylaryl sulfonates,alkyl sulfonates, alkyl sulfates a
6、nd hydroxy-sulfates,alkylphenol- and fatty alcohol ethoxy-sulfates and dialkylsul-fosuccinates. It applies to active materials containing onehydrophilic group per molecule.1.3 The analytical procedures appear in the following order:SectionsReagents 6Primary Standard 8Purity 8.2Alcohols 8.3Free Acid
7、or Alkali 8.4Preparation of Mixed Indicator Solution 9Preparation of Hyamine Solution 10Standardization of Hyamine Solution 11General Procedure for Anionic-Active Material 121.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.Th
8、e values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.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-pria
9、te safety and health practices and determine the applica-bility of regulatory limitations prior to use. A precautionarystatement appears in Section 7. Material Safety Data Sheets areavailable for reagents and materials. Review them for hazardsprior to usage.2. Referenced Documents2.1 ASTM Standards:
10、D1193 Specification for Reagent Water23. Summary of Test Method3.1 An aqueous solution of an anionic-type detergent, towhich is added a small amount of mixed indicator (dimidiumbromide and disulphine blue), is shaken with aqueous Hyaminesolution and chloroform. The pink complex which is formed bythe
11、 reaction between the anionic detergent and the cationic dye,dimidium bromide, is extracted into the chloroform. Incre-ments of additional Hyamine solution are added with athorough mixing after each addition. At first the reaction takesplace between the Hyamine and the excess anionic-typedetergent,
12、during which there is no noticeable change in thecolor (pink) of the chloroform phase. As the equivalence pointbetween the anionic and cationic materials is approached, thedimidium bromide portion of the anionic detergent active-dimidium bromide complex (pink) is gradually released andtransferred to
13、 the aqueous layer.As excess Hyamine is added itreacts with the anionic dye, disulphine blue, to form achloroform-soluble blue complex. During the transition at theend point the chloroform layer, therefore, changes from pink togray, to blue. The gray color is taken as the end point.4. Significance a
14、nd Use4.1 This test method offers a means of determining anionicdetergents commonly found in laundry, dishwashing, and othercleaning materials. Accurate determination of the anionicactive substance is highly important in assessing the cost andeffectiveness of such cleaning substances.1This test meth
15、od is under the jurisdiction of ASTM Committee D12 on Soapsand Other Detergents and is the direct responsibility of Subcommittee D12.12 onAnalysis and Specifications of Soaps, Synthetics, Detergents and their Components.Current edition approved July 1, 2016. Published August 2016. Originallyapproved
16、 in 1972 as D3049 72 T. Last previous edition approved in 2009 asD304989(2009). DOI: 10.1520/D3049-89R16.2For 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 standar
17、ds Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2 This test method is not affected by low molecular weightsulfonates, such as those of toluene and xylene commonlyfound in detergent formula
18、tions, when these substances arepresent up to 15 weight % of active material.5. Interferences5.1 Normal inorganic components of detergentformulations, such as chloride, sulfate, borate, phosphates,perborate, and silicates do not interfere. Soaps, urea, andethylenediaminetetraacetic acid salts do not
19、 interfere. Bleach-ing agents other than perborate should be destroyed prior toperforming this analysis. Low molecular weight sulfonates,such as those of toluene and xylene, do not interfere whenpresent up to 15 % (w) of active material. Since the titration isperformed under acidic conditions (about
20、 pH 2.0), care shouldbe exercised when using this procedure on products containingsignificant amounts of alkaline materials, such as carbonatesand silicates, to ensure that the final solution is being titrated inthe proper pH range.6. Reagents6.1 Purity of ReagentsReagent grade chemicals shall beuse
21、d 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 Society,where such specifications are available.3Other grades may beused, provided it is first ascertained that the reagen
22、t 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 understood to mean reagent water conformingto Specification D1193.6.3 Chloroform.6.4 Ethanol.6.5 Petroleum Ether, boiling ra
23、nge 30 to 50C.6.6 Phenolphthalein Indicator Solution (1 %)Dissolve 1 gof phenolphthalein in 95 % ethanol and dilute to 100 mL.6.7 Sodium Hydroxide, Standard Solution (0.1 N)Preparea 0.1 N solution of sodium hydroxide (NaOH).6.8 Sodium Hydroxide, Standard Solution (1 N)Prepare a1 N solution of NaOH.6
24、.9 Sodium Hydroxide, Standard Solution (50 %)Preparea 50 % solution of NaOH.6.10 Sodium Lauryl Sulfate, Standard Solution, (0.004 M).6.10.1 Weigh accurately between 1.14 and 1.16 g of sodiumlauryl sulfate and dissolve in 200 mL of water.6.10.2 Transfer to a stoppered graduated 1-Lflask and diluteto
25、volume with water.6.10.3 Calculate the molarity of the solution as follows:Molarity 5 W23 P!/288.4 3100! (1)where:W2= sodium lauryl sulfate, g, andP = purity of the sodium lauryl sulfate, %.6.11 Sodium Sulfate (Na2SO4), anhydrous.6.12 Sulfuric Acid, Standard (0.1 N)Prepare a 0.1 Nsolution of sulfuri
26、c acid (H2SO4).6.13 Sulfuric Acid, Standard (0.5 N)Prepare a 0.5 Nsolution of H2SO4.6.14 Sulfuric Acid, Standard (1 N)Prepare a 1 N solutionof H2SO4.7. Safety Precaution7.1 This test method includes the use of small amounts ofchloroform. Appropriate safety practices, such as those in-cluded in the M
27、aterial Safety Data Sheets for chloroform,should be employed. Good ventilation is especially important.8. Primary Standard8.1 The primary standard used in this procedure is sodiumlauryl sulfate.4Three tests are made on this primary standard asfollows:8.2 Purity:8.2.1 This test should be run in dupli
28、cate.8.2.2 Weigh, to the nearest 0.1 mg, 10 6 0.2 g of theprimary standard into a 250-mL round-bottom flask.8.2.3 Add exactly 25 mL of 0.5 N H2SO4. It is not necessaryto standardize this acid.8.2.4 Reflux under a water condenser for 2 h. Heat moder-ately in the beginning until the solution clarifies
29、 and thefoaming ceases; then increase the heat input until a vigorousreflux is attained.8.2.5 Remove the heat source, cool the flask, and then washdown the condenser with approximately 30 mL of ethanolfollowed by 50 mL of water. Add the washings to the reactionflask.8.2.6 Disconnect the condenser an
30、d wash the point and theneck with water. Add these washings to the reaction flask.8.2.7 Add a few drops of 1 % phenolphthalein indicatorsolution and titrate the H2SO4with standardized 1 N NaOHsolution.8.2.8 Determine a blank value by titrating 25 mL of the 0.5N H2SO4with the standardized 1 N NaOH so
31、lution. Thisshould be done in duplicate and the average used.8.2.9 Calculate the percent purity of the primary standard asfollows:Purity, % 5 28.84 3 A 2 B! 3 N#/W (2)where:A = NaOH solution used in sample titration, mL,B = NaOH solution used in blank titration, mL,N = normality of the NaOH solution
32、, and3Reagent Chemicals, American Chemical Society Specifications, 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 Pharm
33、acopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.4Manufactured by British Drug House, Ltd. as Product No. 30176. It is sold asbeing more than 99 % pure. It is available in the United States from Gallard-Schlesinger Chemical Manufacturing Corp., Carle Place, Lon
34、g Island, NY 11514.D3049 89 (2016)2W = primary standard used, g.8.2.10 For best precision and accuracy, temperature andburet corrections should be made when titrating the hydroly-sate of the sodium lauryl sulfate with 1 N NaOH solution.8.3 Alcohols:8.3.1 The primary standard, sodium lauryl sulfate,
35、is sold ashaving not more than 1 weight % (Note 1) of a sum of decyland tetradecyl alcohol sulfates. The following test should berun in duplicate.NOTE 1The term “weight” is temporarily used in this standardbecause of established trade usage. The word is used to mean both “force”and “mass,” and care
36、must be taken to determine which is meant in eachcase (SI unit for force = newton and for mass = kilogram).8.3.2 Mix approximately5gofsodium lauryl sulfate with25 mL of 1 N H2SO4in a 250-mL round-bottom flask.8.3.3 Reflux under a water condenser for at least 2 h. Heatmoderately at first until the so
37、lution clarifies and foamingceases.8.3.4 Cool the contents of the flask and transfer with waterto a separatory funnel.8.3.5 Extract this solution with 50 mL of petroleum ether(boiling range 30 to 50C).8.3.6 Extract four more times with 25-mL portions ofpetroleum ether.8.3.7 Combine the petroleum eth
38、er fractions in a 250-mLbeaker.8.3.8 Allow the aqueous phase to settle out; then decant thepetroleum ether phase through anhydrous Na2SO4to removewater. Collect the effluent in another 250-mL beaker.8.3.9 Evaporate the petroleum ether on a steam bath.8.3.10 Determine the carbon number distribution o
39、f thealcohols present by gas liquid chromatography.58.4 Free Acid Or Alkali:8.4.1 This test, when run on a newly received lot of theprimary standard, gives an estimate of the acidity or alkalinityof the material. Subsequently, it can be used as a check onhydrolysis of the sodium lauryl sulfate durin
40、g storage.8.4.2 Weigh to two decimal places1gofthesodium laurylsulfate.8.4.3 Dissolve the sample in about 150 mL of ethanol thathas been neutralized to phenolphthalein.8.4.4 Add a few drops of phenolphthalein indicator solutionand titrate with either 0.1 N H2SO4or 0.1 N NaOH solution.8.4.5 Record th
41、e millilitres of reagent solution necessary toreturn the solution to neutrality as well as the normality of thetitrant.9. Preparation of the Mixed Indicator Solution9.1 Disulphine Blue.69.2 Dimidium Bromide.79.3 Mixed Indicator Stock SolutionWeigh 0.5 6 0.005 gof dimidium bromide into a 50 mL-beaker
42、. Weigh 0.25 60.005 g of disulphine blue into a second 50-mL beaker. Add 25to 30 mL of 1+10 (v/v) hot ethanol-water solution to eachbeaker. Stir each until the dye is dissolved; then add bothsolutions to a 250-mL volumetric flask. Rinse each beaker withthe 1+10 ethanol-water solution and add the rin
43、sings to thevolumetric flask. Dilute the stock solution to the mark withdeionized water. After 6 months, this solution should bediscarded.9.4 Acid Indicator SolutionAdd 200 mL of water and 20mL of the mixed indicator stock solution to a 500-mLvolumetric flask having a stopper. Add 20 mL of 2.5 M H2S
44、O4.Mix well and dilute to the mark with water. Store in a darkplace.10. Preparation of 0.004 M Hyamine 1622 Solution810.1 Weigh between 1.75 and 1.85 g of Hyamine 1622 anddissolve in water. Transfer to a glass-stoppered 1-L volumetricflask.Add 0.4 mL of 50 % NaOH solution (to keep buret clean)and di
45、lute to the mark with water.10.2 The molecular weight of Hyamine 1622, after removalof one molecule of water by drying, is 448 which correspondsto a weight of 1.792 g required for the preparation of 1 L of a0.004 M solution. If desired, to provide an approximate checkon the sodium lauryl sulfate sta
46、ndardization, the Hyamine 1622may be dried in an oven at 105C and the dried productaccurately weighed for the preparation of the 0.004 M solution.10.3 For the solution quantities larger than 1 L, multiply theamount of Hyamine and NaOH by the number of litres desired.11. Standardization of Hyamine 16
47、22 Solution11.1 Pipet 20 mL of 0.004 N sodium lauryl sulfate solutioninto a stoppered 100-mL graduated mixing cylinder.5A method similar to that of Link, Hickman, and Morrissette, Journal of theAmerican Oil Chemists Society, Vol 36, 1959, p. 20, is suggested.6This product is available as “Patent Blu
48、e VF Extra Concentrate” from GeneralAniline and Film Corp. It is also available as British Drug Houses“ Erioglaucine(Alphazuring 6 or Disulphine Blue V)” which can be obtained in the United Statesfrom Gallard-Schlesinger Chemical Manufacturing Corp. It is not recommendedthat Disulphine Blue from any
49、 other source be substituted for the above without athorough evaluation of the product because investigation has shown that some ofthese products are sensitive to the presence of hydrotropes nor is it recommendedthat the Dimidium Bromide-Disulphine Blue indicator stock solution put out byBritish Drug House be used.7This product is available as British Drug Houses “Dimidium Bromide” whichis available in the United States from Gallard-Schlesinger Chemical ManufacturingCorp.8Hyamine 1622 can be obtained from Fluka Chemical Corp., Ronkonkoma, NY11779, at about 98 %
