ASTM_D_2929_-_89_2011.pdf

Designation:D292989(Reapproved 2011)Standard Test Method forSulfur Content of Cellulosic Materials by X-RayFluorescence1This standard is issued under the fixed designation D2929;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 determination of sulfur contentof cellulosic materials by X-ray fluorescence.1.2 Using appropriate standards,the range of the procedureis from approximately 10 ppm to 20%sulfur.1.3 This test method is proposed specifically as an alterna-tive to Test Methods D871,sections on Significance and Use,Apparatus,Reagents,Procedure and Calculation of HydroxylContent,and Test Methods D817,sections on Summary of TestMethod,Significance and Use,Apparatus,Reagents,andProcedure of Hydroxyl Content.As applied to cellulose estersit measures the combined sulfur and sulfur in the accompany-ing inorganic salts.1.4 To determine combined sulfur,the sample,whensoluble,must first be reprecipitated into dilute acid to removethe noncombined sulfur compounds.1.5 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.6 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 a specifichazard statement,see 7.2.1.2.Referenced Documents2.1 ASTM Standards:2D817 Test Methods of Testing Cellulose Acetate Propionateand Cellulose Acetate ButyrateD871 Test Methods of Testing Cellulose Acetate3.Summary of Test Method3.1 The sulfur content of cellulose,cellulose modification,or cellulose derivative is determined by measuring the intensityof the secondary sulfur K X rays emitted on irradiation of thesample with primary X rays of higher energy from an X-raytube with a target of tungsten or chromium.The sulfur Kradiation is diffracted with a suitable analyzing crystal anddetected with a flow-proportional counter.The entire path ofthe secondary radiation is purged with hydrogen or helium,orevacuated to a pressure of 0.5 mm Hg or less.The intensity ofthe sulfur K rays,as established by a standard counting periodand corrected for background radiation,is then converted topercent sulfur from calibration data.34.Significance and Use4.1 This procedure provides a method for determiningsulfur content in cellulosic materials by nondestructive means.Sulfur may be in the form of sulfate esters that may contributeto thermal instability.Sulfur can also be present as salts thatcan cause haze in solutions.5.Apparatus5.1 Wiley Mill,equipped with 60-mesh screen.5.2 Sample MoldChrome steel die of a size depending onthe sample holder to be used.5.3 Laboratory Press,capable of exerting at least 5000 psi.5.4 X-Ray Spectrograph,with following equipment:tung-sten or chromium target X-ray tube;hydrogen or heliumpurging system or vacuum system to reach 0.5 mm Hg(or less,if desired);20-mil Soller slits;flow-proportional counter with90%argon-10%methane gas mixture;and NaCl,ethylenedi-amine dextro tartrate(EDT),or pentaerythritol(PET)analyz-ing crystal.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.36 on Cellulose and Cellulose Derivatives.Current edition approved June 1,2011.Published June 2011.Originallyapproved in 1970.Last previous edition approved in 2006 as D2929 89(2006).DOI:10.1520/D2929-89R11.2For 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.3This test method is compiled from four techniques,by incorporating certainfeatures of each,as follows:“Sulfur in Cellulose Esters by X-ray EmissionSpectroscopy,”Eastman Kodak Co.;“Sulfur in Cellulose Acetate by X-rayFluorescence,”Tennessee Eastman Co.;“X-ray Fluorescence Analysis of ModifiedCottons”by Tripp,Piccolo,Mitcham and OConnor.Textile Research Journal,Vol34,1964,p.773,and FMC Corp.,American Viscose Div.information furnished byL.H.Phifer and W.B.Swann.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 NOTE1Radiation from a chromium target tube appears to be moreeffective than radiation from a tungsten target tube for exciting sulfur K.This may be because a larger part of the“white”radiation of thechromium tube is at the longer wavelength region of the spectrum,orbecause of the use of thinner windows in the chromium tube.However,either the chromium or the tungsten target tube i