ASTM_D_7620_-_10_2015.pdf

Designation:D762010(Reapproved 2015)Standard Test Method forDetermination of Total Sulfur in Liquid Hydrocarbon BasedFuels by Continuous Injection,Air Oxidation and UltravioletFluorescence Detection1This standard is issued under the fixed designation D7620;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 total sulfurin liquid hydrocarbon based fuel with a final boiling point of upto 450 C.It is applicable to analysis of natural,processed andfinal product materials containing sulfur in the range of4.0 mgkg to 830 mg kg(see Note 1).NOTE1For liquid hydrocarbons containing less than 4.0 mg kg totalsulfur or more than 830 mg kg total sulfur,Test Method D5453 may bemore appropriate.1.2 This test method is applicable for total sulfur determi-nation in liquid hydrocarbons containing less than 0.35%(m m)halogen(s).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.For specific hazardstatements,see 4.1,8.3,and Section 9.2.Referenced Documents2.1 ASTM Standards:2D1298 Test Method for Density,Relative Density,or APIGravity of Crude Petroleum and Liquid Petroleum Prod-ucts by Hydrometer MethodD4052 Test Method for Density,Relative Density,and APIGravity of Liquids by Digital Density MeterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4175 Terminology Relating to Petroleum,PetroleumProducts,and LubricantsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD5453 Test Method for Determination of Total Sulfur inLight Hydrocarbons,Spark Ignition Engine Fuel,DieselEngine Fuel,and Engine Oil by Ultraviolet FluorescenceD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricantsD6792 Practice for Quality System in Petroleum Productsand Lubricants Testing Laboratories3.Terminology3.1 Definitions:3.1.1 See Terminology D4175 for definitions of other termsused in this test method.3.1.2 oxidative pyrolysis,nprocess in which a sampleundergoes complete combustion in an appropriate oxygencontaining environment at a sufficiently elevated temperature.3.1.2.1 DiscussionOrganic compounds pyrolytically oxi-dize to carbon dioxide and water and oxides of other elementsthat are in the sample.4.Summary of Test Method4.1 A small,very controlled flow of hydrocarbon sample iscontinuously injected during measurement.It is introduced viaa syringe into a high temperature combustion tube containingair where sulfur is oxidized to sulfur dioxide(SO2).Waterproduced during the sample combustion is removed,asrequired,and the sample combustion gases are next exposed toultraviolet(UV)light.The SO2absorbs the energy from theUV light and is converted to excited sulfur dioxide(SO2*).Fluorescence emitted from the excited SO2*as it returns to astable state SO2is detected by a photomultiplier tube and theresulting signal is a measure of the sulfur contained in thesample.(WarningExposure to excessive quantities of ultra-violet light is injurious to health.The operator shall avoid1This 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 1,2015.Published July 2015.Originally approvedin 2010.Last previous edition approved in 2010 as D7620 10.DOI:10.1520/D7620-10R15.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 exposing their body,especially their eyes,not only to directUV light but also to secondary or scattered radiation that ispresent.)4.2 Fig.1 illustrates a basic block diagram describing sulfurdetermination.Sample collection and conditioning,sampleintroduction,detection system and data handling are depicted.5.Significance and Use5.1 Some process catalysts used in refining can be poisonedwhen trace amounts of sulfur bearing materials are contained inthe feedstocks.There are also government regulations as tohow much sulfur is permitt