1、Designation:D121821Standard Test Method forRefractive Index and Refractive Dispersion of HydrocarbonLiquids1This standard is issued under the fixed designation D1218;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last re
2、vision.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 measurement of r
3、efractiveindex,accurate to four decimal places or better,of transparentand light-colored hydrocarbons in the range of 1.3300 to1.5000 at temperatures from 20 C to 30 C by manual(optical-mechanical)or automatic(digital)procedure.1.2 The manual(optical-mechanical)procedure also coversthe measurement o
4、f refractive dispersion accurate to the fourthdecimal place or better.NOTE1The test method may be suitable for measuring the refractiveindices of liquids above 1.5000 and at temperatures both below 20 C andabove 30 C;however,the test method precision may not apply.Verifi-cation of the accuracy of su
5、ch measurements will depend upon theavailability of reliable,certified reference standards that demonstrate theperformance of the instrument used under the particular measuringconditions.1.3 The test method may not be applicable to liquids that arestrongly colored,or that have bubble points so near
6、the testtemperature that a reading cannot be obtained before substan-tial weathering takes place.Liquid color should be limited toNo.4 ASTM Color or lighter,as determined by Test MethodD1500.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in
7、 thisstandard.1.5 WARNINGMercury has been designated by manyregulatory agencies as a hazardous substance that can causeserious medical issues.Mercury,or its vapor,has been dem-onstrated to be hazardous to health and corrosive to materials.Use Caution when handling mercury and mercury-containingprodu
8、cts.See the applicable product Safety Data Sheet(SDS)for additional information.The potential exists that sellingmercury or mercury-containing products,or both,is prohibitedby local or national law.Users must determine legality of salesin their location.1.6This standard does not purport to address a
9、ll 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.1.7 This international standard was developed in ac
10、cor-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
11、Standards:2D1193 Specification for Reagent WaterD1500 Test Method for ASTM Color of Petroleum Products(ASTM Color Scale)D6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceD6300 Practice for Determination of Pre
12、cision and BiasData for Use in Test Methods for Petroleum Products,Liquid Fuels,and LubricantsE1 Specification for ASTM Liquid-in-Glass Thermometers2.2 ASTM Adjuncts:Determination of Precision and Bias Data for Use in TestMethods for Petroleum Products and Lubricants,Version4.0.6533.Terminology3.1 D
13、efinitions:3.1.1 refractive dispersion,nthe difference between therefractive indices of a substance for light of two differentwavelengths,both indices being measured at the same tem-perature.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubri
14、cants and is the direct responsibility ofSubcommittee D02.04.0D on Physical and Chemical Methods.Current edition approved Nov.1,2021.Published November 2021.Originallyapproved in 1952.Last previous edition approved in 2016 as D1218 12(2016).DOI:10.1520/D1218-21.2For referenced ASTM standards,visit t
15、he 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.3Out of print.No longer available from ASTM International Headquarters.*A Summary of Changes section app
16、ears 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.13.1.1.1 DiscussionFor convenience in calculat
