1、Designation:D226910(Reapproved 2015)Standard Test Method forEvaluation of White Mineral Oils by Ultraviolet Absorption1This standard is issued under the fixed designation D2269;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year
2、 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 describes a procedure for the exami-nation and evaluation of NF and USP grade white mineral oils.1.2 T
3、his test method is not applicable to oils containingadditives soluble in dimethyl sulfoxide(DMSO)that exhibitfluorescence or fluorescence quenching properties.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
4、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 specificwarning statements,see 7
5、.1.1 7.1.3.2.Referenced Documents2.1 ASTM Standards:2D1840 Test Method for Naphthalene Hydrocarbons in Avia-tion Turbine Fuels by Ultraviolet SpectrophotometryE131 Terminology Relating to Molecular SpectroscopyE275 Practice for Describing and Measuring Performance ofUltraviolet and Visible Spectroph
6、otometers2.2 Other Standard:U.S.Pharmacopeia USP XIII/National Formulary(NFXVIII)33.Terminology3.1 Definitions:3.1.1 For definitions of terms and symbols relating toabsorption spectroscopy see Terminology E131.Terms ofparticular significance are the following:3.1.2 radiant energy,nenergy transmitted
7、 as electromag-netic waves.3.1.3 radiant power,P,nthe rate at which energy istransported in a beam of radiant energy.3.2 Definitions of Terms Specific to This Standard:3.2.1 absorbance,A,nthe logarithm to the base 10 of thereciprocal of the transmittance,T.In symbols:A 5 log101/T!5 2log10Twhere T is
8、 the transmittance as defined in 3.2.5.3.2.2 absorptivity,a,nthe absorbance divided by theproduct of sample pathlength and concentration.In symbols:a 5 A/bcwhere A is the absorbance as defined in 3.2.1,b is thesample pathlength as defined in 3.2.4,and c is the concentra-tion as defined in 3.2.3.3.2.
9、3 concentration,c,nthe quantity of sample expressedin grams per litre.3.2.4 sample pathlength,b,nthe distance in centimetres,measured in the direction of propagation of the beam of radiantenergy,between the surfaces of the specimen on which theradiant energy is incident and the surface of the specim
10、en fromwhich it is emergent.3.2.5 transmittance,T,nthe ratio of the radiant powertransmitted by the mineral oil extract in its cell to the radiantpower transmitted by the solvent control in its cell.Expressedby:T 5 Pe/Pcwhere Peis the radiant power transmitted by the mineraloil extract and Pcis the
11、radiant power transmitted by thesolvent control.4.Summary of Test Method4.1 Asample of oil is extracted with dimethyl sulfoxide andthe ultraviolet absorbance of the extract is determined in the1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lub
12、ricants and is the direct responsibility ofSubcommittee D02.04.0F on Absorption Spectroscopic Methods.Current edition approved April 1,2015.Published June 20105.Originallyapproved in 1964.Last previous edition approved in 2010 as D2269 10.DOI:10.1520/D2269-10R15.2For referenced ASTM standards,visit
13、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.3Available from The United States Pharmacopeia(USP),12601 TwinbrookParkway,Rockville,MD 20852.Copyright
14、 ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 range from 260 nm to 350 nm.The absorbance is comparedwith that of a naphthalene standard.5.Significance and Use5.1 The ultraviolet absorption of white mineral oils is usedto determine their suitabil
15、ity for use in food,drug,andcosmetic applications.5.2 The U.S.Pharmacopeia and the National Formularyspecifications for mineral oil require the measurement ofultraviolet absorption.6.Apparatus6.1 Spectrophotometer,equipped to handle liquid samples in1 cm path length cells.The instrument shall be cap
16、able ofmeasuring absorbance with a repeatability of 61.0%or betterfrom an average at the 0.4 absorbance level in the spectralregion near 290 nm with a nominal band width of 1 nm or less.NOTE1For recommended methods of testing spectrophotometers tobe used in this test method refer to Practice E275.6.2 Fused Quartz Cells,two,having path lengths of 1.00 cm6 0.005 cm,or better.The distance in centimetres does notinclude the thickness of the cell in which the sample iscontained.6.3 Separatory Funnels
