ASTM_D_3340_-_07.pdf

Designation:D3340 07Standard Test Method forLithium and Sodium in Lubricating Greases by FlamePhotometer1This standard is issued under the fixed designation D3340;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.Scope*1.1 This test method covers determination of the lithium andsodium content of lubricating greases by means of a flamephotometer.1.2 A multi-element analysis method for greases,whichincludes the measurement of lithium and sodium concentra-tions using inductively couple plasma-atomic emission spec-troscopy(ICP-AES),is available in Test Method D7303.1.3 The values stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.The preferred units are mass%.1.4 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.2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceD6792 Practice for Quality System in Petroleum Productsand Lubricants Testing LaboratoriesD7303 Test Method for Determination of Metals in Lubri-cating Greases by Inductively Coupled Plasma AtomicEmission Spectrometry3.Summary of Test Method3.1 The sulfated ash of the grease is extracted with waterand the lithium and sodium content of the resulting solution isdetermined by means of a suitable flame photometer.4.Significance and Use4.1 Lubricating greases can contain the lithium soap ofhydroxy stearic acid or the sodium soap of various fatty acidsas thickeners.The determination of total lithium or totalsodium is a measure of the amount of thickener in the grease.5.Apparatus5.1 Flame Photometer,suitably equipped to determinelithium and sodium over a range from 0 to 15 mg/Llithium andfrom 0 to 5 mg/L sodium.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 as definedby Type II of Specification D1193.6.3 Lithium Sulfate,Stock Solution1.188 g of lithiumsulfate dried to constant weight at 180C(356F),is dissolvedin water and made up to 1 L.This will contain 150 mg/Llithium.6.4 Sodium Sulfate,Stock Solution0.1544 g of sodiumsulfate,dried to constant weight at 105C(221F),is dissolvedin water and made up to 1 L.This will contain 50 mg/Lsodium.6.5 Sulfuric Acid(rel.den.1.84)Concentrated sulfuricacid(H2SO4).7.Sampling7.1 A homogeneous sample shall be obtained to ensurequantitative analytical results.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.03 on Elemental Analysis.Current edition approved Dec.1,2007.Published January 2008.Originallyapproved in 1974.Last previous edition approved in 2003 as D334098(2003).DOI:10.1520/D3340-07.2For 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 Annual Standards for LaboratoryChemicals,BDH Ltd.,Poole,Dorset,U.K.,and the United States Pharmacopeiaand National Formulary,U.S.Pharmacopeial Convention,Inc.(USPC),Rockville,MD.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.8.Procedure8.1 Weigh to the nearest 1 mg approximately 1 g of thegrease into a platinum dish or crucible.Heat the dish until thesample can be ignited with a flame.Maintain at such atemperature that the sample burns at a uniform and moderaterate,leaving only ash and carbon when the burning ceases.8.2 Cool the dish and completely moisten the residue by thedropwise addition of concentrated sulfuric acid.Heat the dishat a low temperature,taking care to avoid spattering of thecontent