ASTM_D_3049_-_89_2009.pdf

Designation:D304989(Reapproved 2009)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 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 the amountof synthetic anionic ingredient in a surfactant by direct titrationwith 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 additionof 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-soluble,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,alkylsulfonates,alkylsulfatesandhydroxy-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:SectionsReagents6Primary Standard8Purity8.2Alcohols8.3Free Acid or Alkali8.4Preparation of Mixed Indicator Solution9Preparation of Hyamine Solution10Standardization of Hyamine Solution11General Procedure for Anionic-Active Material121.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.The 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-priate 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: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 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,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 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 and 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 method 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 Oct.1,2009.Published March 2010.Originallyapproved in 1972 as D3049 72 T.Last previous edition approved in 2003 asD304989(2003).DOI:10.1520/D3049-89R09.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.2 This test method is not affected by low molecular weightsulfonates,such as those of toluene and xylene commonlyfound in detergent