ASTM_D_5762_-_12.pdf

Designation:D576212Standard Test Method forNitrogen in Petroleum and Petroleum Products by Boat-InletChemiluminescence1This standard is issued under the fixed designation D5762;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 the determination of nitrogen inliquid hydrocarbons,including petroleum process streams andlubricating oils in the concentration range from 40 to 10 000g g nitrogen.For light hydrocarbons containing less than 100g/g nitrogen,Test Method D4629 can be more appropriate.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 and health practices and determine the applica-bility of regulatory limitations prior to use.Specific warningstatements are given in Section 6,7.1,8.2,and 8.2.2.2.Referenced Documents2.1 ASTM Standards:2D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD4629 Test Method for Trace Nitrogen in Liquid PetroleumHydrocarbons by Syringe/Inlet Oxidative Combustion andChemiluminescence DetectionD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System Performance3.Summary of Test Method3.1 A hydrocarbon sample is placed on a sample boat atroom temperature.The sample and boat are advanced into ahigh-temperature combustion tube where the nitrogen is oxi-dized to nitric oxide(NO)in an oxygen atmosphere.The NOcontacts ozone and is converted to excited nitrogen dioxide(NO2).The light emitted as the excited NO2decays is detectedby a photomultiplier tube,and the resulting signal is a measureof the nitrogen contained in the sample.4.Significance and Use4.1 Many nitrogen compounds can contaminate refinerycatalysts.They tend to be the most difficult class of compoundsto hydrogenate,so the nitrogen content remaining in theproduct of a hydrotreator is a measure of the effectiveness ofthe hydrotreating process.In lubricating oils the concentrationof nitrogen is a measure of the presence of nitrogen containingadditives.This test method is intended for use in plant controland in research.5.Apparatus5.1 Boat Inlet System,capable of being sealed to the inlet ofthe combustion tube and swept with inert gas.The boats arefabricated from platinum or quartz.To aid quantitative liquidinjection,it is recommended to add a small piece of quartzwool or suitable equivalent(see 6.8)to the boat.The boat drivemechanism should be able to fully insert the boat into thefurnace tube inlet section.A drive mechanism that advancesand withdraws the sample boat into and out of the furnace at acontrolled and repeatable rate is required.5.2 Chemiluminescence Detector,capable of measuringlight emitted from the reaction between nitric oxide and ozone,and containing a variable attenuation amplifier,integrator,andreadout.NOTE1Detectors designed to maintain the chemiluminescence reac-tion cell at reduced pressure are acceptable for use and were included inthe instruments used to determine the precision of this test method.5.3 Combustion Tube,fabricated from quartz.The inlet endof the tube shall be large enough to accept the sample boat andto have side arms for introduction of oxygen and inert gas.Theconstruction is such that the carrier gases sweep the inlet zonetransporting all of the volatilized sample into a high-temperature oxidation zone.The oxidation section should belarge enough to ensure complete oxidation of the sample.Combustion tubes recommended for the two furnaces in 5.5.11This 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 April 15,2012.Published June 2012.Originallyapproved in 1995.Last previous edition approved in 2011 as D576211.DOI:10.1520/D5762-12.2For 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 States1 and 5.5.2 are described in 5.3.1 and 5.3.2.Other configurationsare acceptable if precision and bias are not degraded.5.3.1 Quartz combustion tube for use with the single-zonefurnace is illustrated in Fig.1.A water-