ASTM_D_2180_-_89_2008.pdf

Designation:D218089(Reapproved 2008)Standard Test Method forActive Oxygen in Bleaching Compounds1This standard is issued under the fixed designation D2180;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 inorganic“active oxygen”in bleaching compounds such as perborates,percarbonates,and peroxides but not in persulfates or monop-ersulfates.1.2 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.Material SafetyData Sheets are available for reagents and materials.Reviewthem for hazards prior to usage.2.Referenced Documents2.1 ASTM Standards:2D459 Terminology Relating to Soaps and Other DetergentsD1193 Specification for Reagent Water3.Terminology3.1 Definitions:3.1.1 active oxygenthe measure of the oxidizing power ofcompounds such as inorganic perborates,percarbonates,orperoxides which,in effect,release hydrogen peroxide in acidsolutions.It is expressed in terms of oxygen(O)with gram-equivalent weight of 8.00.4.Summary of Test Method4.1 Active oxygen is determined by titration of an acidifiedaqueous solution of the compound with a standard solution ofpotassium permanganate.NOTE1Use of a molybdate-catalyzed iodometric method for thispurpose has been suggested,but the possible reaction of the liberatediodine on organics present must be considered.It is believed there is lesslikelihood of reaction with permanganate,provided the titration isperformed in such a manner as to avoid any considerable excess ofpermanganate.5.Interferences5.1 Thepossibilityofinterferencefromorganicconstituents,which may react with permanganate,must beconsidered with each compound encountered.A sluggishreaction or vague end point,will suggest interference.Inor-ganic builders or detergents,such as silicates,phosphates,orcarbonates,do not interfere.Organic detergents or wettingagents may interfere.EDTA-type sequestrants do interfere(seeTerminology D459).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 Society,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 understood to mean reagent water conformingto Specification D1193.6.3 Potassium Permanganate,Standard Solution(0.1 N)Dissolve 3.2 g of potassium permanganate(KMnO4)in 100mL of water and dilute the solution with water to 1 L.Allowthe solution to stand in the dark for two weeks and then filterthrough a fine-porosity sintered-glass crucible.Do not wash thefilter.Store the solution in glass-stoppered,amber-colored glassbottles.NOTE2Do not permit the filtered solution to come into contact withpaper,rubber,or other organic material.6.3.1 Weigh accurately to the nearest 0.1 mg about 0.3 gstandard sodium oxalate(Na2C2O4,previously dried at 105C).1This test method is under the jurisdiction of ASTM Committee D12 on Soapsand Other Detergentsand is the direct responsibility of Subcommittee D12.12 onAnalysis and Specifications of Soaps,Synthetics,Detergents and their Components.Current edition approved July 1,2008.Published July 2008.Originally approvedin 1963.Last previous edition approved in 2003 as D2180 89(2003).DOI:10.1520/D2180-89R08.2For 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,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.(USPC),Rockville,MD.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 Transfer to a 400-mL beaker.Add 250 mL of H2SO4(5+95),freshly boiled for at least 10 min and cooled to 27 6 3C.Stiruntil the oxalate has dissolved.Add 0.1 N KMnO4solutionrapidly from a buret(25 to 30 mL/min)while stirring slowlybut constantly until about 40 mL have been added.Let standuntil the pink color disappears.Heat the sol