ASTM_D_7525_-_14.pdf

Designation:D752514Standard Test Method forOxidation Stability of Spark Ignition FuelRapid SmallScale Oxidation Test(RSSOT)1This standard is issued under the fixed designation D7525;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 laboratory test method covers the quantitativedetermination of the stability of spark ignition fuel,includingthose containing alcohols or other oxygenates,under acceler-ated oxidation conditions,by an automatic instrument(WarningThis test method is not intended for determiningthe stability of gasoline components,particularly those with ahigh percentage of low boiling unsaturated compounds,asthese can cause explosive conditions with the apparatus.2)1.2 This test method measures the induction period,underspecified conditions,which can be used as an indication of theoxidation and storage stability of spark ignition fuel.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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:3D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricants3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 break point,npressure in the test apparatus,which is10%below the maximum pressure of the actual test run.3.1.2 induction period,ntime elapsed between starting theheating procedure of the sample vessel and the break point,measured in minutes.4.Summary of Test Method4.1 A 5 mL sample is introduced into a pressure vesselwhich is then charged with oxygen to 500 kPa at a temperatureof 15 to 25C.The test is initiated by starting the heater andheating the pressure vessel to a temperature of 140C.4.2 The pressure is recorded continuously until the break-point is reached.Alternatively,the test may be terminated whena predetermined minimum requirement is reached.5.Significance and Use5.1 The induction period may be used as an indication of theoxidation and storage stability of spark ignition fuel.5.2 Compared to some other oxidation and storage stabilitytest methods,this test method uses a small sample and gives aresult in a short time period.6.Apparatus6.1 GeneralThis test method uses an automatically con-trolled oxidation tester4(Fig.1)comprising an oxidationpressure vessel containing a test sample cup capable of beingrapidly heated,fitted with a pressure sensor capable of mea-suring pressures up to 2000 kPa and a temperature sensorcapable of reading to 0.1C.Pressure and temperature in theoxidation vessel are recorded continuously during the test.Theoxidation pressure vessel is fitted with filling and relief valvesand a means of automatically releasing the pressure at the endof the test.The integrated cooling fan cools the pressure vessel1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.14 on Stability and Cleanliness of Liquid Fuels.Current edition approved Oct.1,2014.Published November 2014.Originallyapproved in 2009.Last previous edition approved in 2009 as D7525 09.DOI:10.1520/D7525-14.2Further information can be found in the June 1978,January 1979,and June1986 editions of the Institute of Petroleum Review.3For 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.4The sole source of supply of the apparatus known to the committee at this timeis Anton Paars PetroOxy apparatus,available from Anton Paar ProveTec GmbH,Ludwig-Erhard-Ring 13,15827 Blankenfelde-Mahlow,Germany,www.anton-.If you are aware of alternative suppliers,please provide this informationto ASTM International Headquarters.Your comments will receive careful consid-eration at a meeting of the responsible technical committee,1which you may attend.*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 States1 from the test temperature to ambient temperature by a flow ofair.See Annex A1 for detailed information.6.2 Volumetric Device,clean and free from contaminationsof previous samples,capable of de