ASTM_D_3228_-_20.pdf

Designation:D322820Standard Test Method forTotal Nitrogen in Lubricating Oils and Fuel Oils by ModifiedKjeldahl Method1This standard is issued under the fixed designation D3228;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 This test method covers the determination of nitrogen inlubricating oils when present in the concentration from 0.03%to 0.10%by mass,and for the determination of nitrogen in fueloils when present in the concentration from 0.015%to 2.0%by mass.This test method is also applicable to the analysis ofadditive concentrates and additive packages.NOTE1This test method may not be applicable to certain materialscontaining NO or NN linkage.However,the samples used in thecooperative program to establish the precision of the test method werecompounded with currently available ashless additives containing nitro-gen.Complete recovery of the nitrogen present in these additives wasobtained.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.For specific warning statements,see 6.6,6.9,and 8.8.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceE200 Practice for Preparation,Standardization,and Storageof Standard and Reagent Solutions for Chemical Analysis3.Summary of Test Method3.1 The sample is digested in a mixture of concentratedsulfuric acid,potassium sulfate,and a catalyst of mercuricoxide,titanium dioxide,or copper sulfate.After digestion,sodium sulfide is added to precipitate the mercury if used as acatalyst,and the mixture is made alkaline with caustic.Nitrogen,now in the form of ammonia,is distilled into a boricacid solution.The ammonia is titrated with standard sulfuricacid using methyl purple as an indicator.4.Significance and Use4.1 The concentration of nitrogen is a measure of thepresence of nitrogen-containing additives.Knowledge of itsconcentration can be used to predict performance.5.Apparatus5.1 Buret,50 mL,graduated in 0.1 mL subdivisions,one foreach titrant.Other size burettes may also be used.5.2 Flask,Erlenmeyer,300 mL.Other sizes are also accept-able.5.3 Heater,electrical or gas.5.4 Kjeldahl Distillation Apparatus.NOTE2Commercially available semiautomatic Kjeldahl apparatus areacceptable.In such cases manufacturer prescribed sizes of burettes andflasks may be used.5.5 Kjeldahl Flask,at least 500 mL volume.5.6 Kjeldahl Digestion Apparatus.6.Reagents6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.Unless otherwise indicated,it is intended that1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.03 on Elemental Analysis.Current edition approved July 1,2020.Published July 2020.Originally approvedin 1973.Last previous edition approved in 2019 as D3228 19.DOI:10.1520/D3228-20.2For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.all 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 reage