ASTM_D_2003_-_93_scan.pdf

ASTM D2003 93-035=l530 0533548 OLb m Designation:D 2003-93 AMERICAN SOCIETY FOR TESTING AND MATERIALS 1916 Race St.Philadelphia,Pa 19103 Reprinted from the Annual Book of ASTM Standards.Copyright ASTM If not listed in the current combined index.will appear in the next edition.An American NaticoaI Stanclard Standard Practice for Isolation of Representative Saturates Fraction from High-Olefinic Petroleum Naphthas This standard is issued under the ftxed designation D 2003;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last nvision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(t)indicates an editorial change since the last revision or reapproval.1.Scope 1.1 This practice covers the isolation of a representative saturates fraction from depentanized hydrocarbon mixtures that distill below 22lC(430F).It is applicable for samples containing from 0 to 35 volume%olefinic hydrocarbons.However,for samples that contain less than 1 volume%of olefinic hydrocarbons the procedures given in Test Method D 2002,are recommended.1.2 The values stated in SI units are to be regarded as the standard.The values given in parentheses are for informa-tion only.1.3 This standard does not purport to address all of the safety problems,if any,associated with its use.It is the responsibility of the user of this standard to establish appro-priate safety und health practices and determine the applica-bility of regulatory limitations prior to use.Specific precau-tionary statements are given in Notes 1,2,3,4,and 5.2.Referenced Documents 2.1 ASTM Standards:D 13 19 Test Method for Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Adsorp-tion2 D2002 Test Methods for Isolation of Representative Sat-urates Fraction from Low-Olefinic Petroleum Naphthas3,3.Terminology 3.1 Description of a Term Specijc to This Standard:3.1.1 saturates fraction-the portion of the sample ob-tained from the silica gel fractionation procedure described in this practice,and essentially a mixture of paraffinic and naphthenic hydrocarbons.4.Summary of Practice 4.1 A measured amount of sample is charged to the top of a glass column packed with fine activated silica gel.The adsorbed sample is then desorbed with alcohol,with the saturated hydrocarbons which have the lowest adsorption affinity issuing from the bottom of the silica gel column first.The total percolate collected prior to the elution of the yellow fluorescing oleflnic marker is representative of the saturates in the sample.t This practice is under the jurisdiction of ASTM Committee D-2 on Petroleum Products and Lubricants and is the direct responsibility of Subcommittee W2.04 on Hydrocarbon Analysis.Currenl edition approved Aug.IS,1993.Published October 1993.Originally published as D 2003-62 T.Last previous edition D 2003-9 I.2 Annual Book ofASTM Standards.VolOS.01.3 Annual Book o/ASTM Standards.Vol 05.02.5.Significance and Use 5.1 The determination of paraffins and naphthenes by the refractivity intercept requires a sample free from olefins and aromatics.This practice is applicable for the isolation of saturates fractions from samples containing up to 35 volume%olefins and 65 volume%total oletins plus aro-matics.6.Apparatus 6.1 Adsorption Column,as shown in Fig.1.6.2 Receiver,graduated,of capacity sufficient to collect the total saturates as one fraction.The inside diameter of the graduated portion should not exceed 10 mm.6.3 Vibrator,for packing silica gel.6.4 Hypodermic Syringe,for charging sample.6.5 Ultraviol$t Light Source,with radiation predomi-nantly at 3650 A.6.6 Refrigerant Circulation System,to circulate liquid cooled to 4 to 16C(40 to 60F)through the adsorption column jacket.7.Reagents 7.1 Isopropyl Alcohol(Warning-See Note 1).NOTE I:Warning-Flammable,7.2 Pressuring Gas(Warning-See Note 2),delivered to the top of the column at a regulated pressure.NOTE 2:Warning-Compressed gas.7.3 Silica Gel,149 to 74 pm(100 to 200-mesh).4 1.4 Standard Dyed GeL5 8.Procedure 8.1 Clean the adsorption column with chromic-sulfuric acid(Warning-See Note 3),water,and acetone(Waming-See Note 4).NOTE 3:Warning-Causes severe bums.A recognized carcinogen.NOTE 4:Warning-Extremely flammable.Vapors may cause tire.8.2 Introduce a small metallic or glass pellet,approxi-mately 1.6 mm(r/16 in.)in diameter,to prevent the flow of silica gel from the bottom of the column,and sufficiently nonspherical to permit liquid elution.8.3 Clamp the column in a vertical position and pack the Silica gel,available from W.R.Grace and Co.,Davison Chemical Division,Baltimore,MD 21203,by specifying Code 923,has been found satisfactory for this Purpose.5 The standard dyed gel may be obtained from UOP Process Div.,Drganics Dept.25 E.Algonquin Rd.,Des Plaines,IL 601317-5017,by rapresting“PLA Standard Dyed Gel”,UOP Product No.675.NOTICE:This standard has either been superseded and replaced by a new version or discontinued.