ASTM_D_6756_-_10_2015.pdf

Designation:D675610(Reapproved 2015)Standard Test Method forDetermination of the Red Dye Concentration and Estimationof the ASTM Color of Diesel Fuel and Heating Oil Using aPortable Visible Spectrophotometer1This standard is issued under the fixed designation D6756;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 the red dyeconcentration of diesel fuel and heating oil and the estimationof the ASTM color of undyed and red-dyed diesel fuel andheating oil.The test method is appropriate for use with dieselfuel and heating oil of Grades 1 and 2 described in Specifica-tions D396,D975,D2880 and D3699.Red dye concentrationsare determined at levels equivalent to 0.1 mg L to 20 mg L ofSolvent Red 26 in samples withASTM colors ranging from 0.5to 5.The ASTM color of the base fuel of red-dyed sampleswith concentration levels equivalent to 0.1 mg L to 20 mg Lof Solvent Red 26 is estimated for the ASTM color range from0.5 to 5.The ASTM color of undyed samples is estimated overthe ASTM color range of 0.5 to 5.1.2 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.2.Referenced Documents2.1 ASTM Standards:2D396 Specification for Fuel OilsD975 Specification for Diesel Fuel OilsD1500 Test Method for ASTM Color of Petroleum Products(ASTM Color Scale)D2880 Specification for Gas Turbine Fuel OilsD3699 Specification for KerosineD4052 Test Method for Density,Relative Density,and APIGravity of Liquids by Digital Density MeterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6045 Test Method for Color of Petroleum Products by theAutomatic Tristimulus MethodD6708 Practice for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a MaterialE203 Test Method for Water Using Volumetric Karl FischerTitrationE1655 Practices for Infrared Multivariate QuantitativeAnalysisE2056 Practice for Qualifying Spectrometers and Spectro-photometers for Use in Multivariate Analyses,CalibratedUsing Surrogate Mixtures3.Terminology3.1 Definitions:3.1.1 ASTM color,nthe name of an empirical scale ofexpressing the color of a petroleum liquid darker than Sayboltcolor based on a scale of 0.5(lightest)to 8 Dil(darkest)anddetermined by Test Method D1500.3.1.2 surrogate calibration,na multivariate calibrationthat is developed using a calibration set which consists ofmixtures with pre-specified and reproducible compositions thatcontain substantially fewer chemical components than thesamples which will ultimately be analyzed.E20563.1.3 surrogate method,na standard test method that isbased on a surrogate calibration.E20563.2 Definitions of Terms Specific to This Standard:3.2.1 red dye,nsubstance that,when added to fuel,absorbs green light and imparts a red color to the product.Forthis test method,red dyes are:3.2.1.1 product dyes,nalkyl derivatives of azobenzene-4-azo-2-naphthol(methyl derivatives of Color Index No.26105)which are more soluble in diesel fuel.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.05 on Properties of Fuels,Petroleum Coke and Carbon Material.Current edition approved Oct.1,2015.Published December 2015.Originallyapproved in 2002.Last previous edition approved in 2010 as D6756 10.DOI:10.1520/D6756-10R15.2For 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 3.2.1.2 solvent red 26,nan azobenzene-4-azo-2-naphtholdye of a specific chemical structure that is used to gage theamount of red dye present in a given sample.4.Summary of Test Method4.1 A sample is introduced into the liquid specimen cell.The cell is placed into the light path of the apparatus.A beamof visible light is imaged through the sample onto a detector,and the detector response is determined.Wavelengths of thespectrum,which correlate highly with the red dye concentra-tion and the ASTM color,are selected for analysis usingselective bandpass filters.A multivariate mathematical modelconv