1、Designation:E240306(Reapproved 2012)Standard Test Method forSulfated Ash of Organic Materials by Thermogravimetry1This standard is issued under the fixed designation E2403;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of l
2、ast 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 standard describes the determination of sulfatedash content(sometimes called residue-on-ignition)of organicmaterials by
3、 thermogravimetry.The method converts commonmetals found in organic materials(such as sodium,potassium,lithium,calcium,magnesium,zinc,and tin)into their sulfatesalts permitting estimation of their total content as sulfates oroxides.The range of the test method is from 0.1 to 100%metal content.1.2 Th
4、e 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 s
5、afety and health practices and to determine theapplicability of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D874 Test Method for Sulfated Ash from Lubricating Oilsand AdditivesD914 Test Methods for EthylcelluloseD3516 Test Methods for Ashing CelluloseE473 Terminolog
6、y Relating to Thermal Analysis and Rhe-ologyE1131 Test Method for Compositional Analysis by Thermo-gravimetryE1142 Terminology Relating to Thermophysical PropertiesE1582 Practice for Calibration of Temperature Scale forThermogravimetryE2040 Test Method for Mass Scale Calibration of Thermo-gravimetri
7、c Analyzers2.2 Other Standards:The United States Pharmacopeia XXII and The NationalFormularyXVII,UnitedStatesPharmacopeialConvention,Rockville,MD,1990,Section 281,p.15273.Terminology3.1 DefinitionsTechnical terms used in this standard aredefined in Terminologies E473 and E1142.3.1.1 sulfated ash,nth
8、e residue remaining after a speci-men has been oxidized,and the residue subsequently treatedwith sulfuric acid and heated to constant weight.3.1.2 residue-on-ignition,ROI,na commonly used aliasfor sulfated ash.3.1.3 volatiles,nfor the purpose of this test,those mate-rials evolving as gas at temperat
9、ures below 160C in an airatmosphere.4.Summary of Test Method4.1 A test specimen is ignited and burned in an air atmo-sphere at temperatures up to 600C until only ash remains.After cooling,the residue is treated with sulfuric acid andheated to 800C to constant weight.The residue remaining isidentifie
10、d as sulfated ash.4.2 This test method is similar to Test Method D874 forlubricating oils and additives,Test Methods D914 for ethylcellulose,Test Methods D3516 cellulose,and that of TheUnited States Pharmacopeia XXII and makes use of thermo-gravimetric apparatus to perform the determination.5.Signif
11、icance and Use5.1 The sulfated ash may be used to indicate the level ofknown metal-containing additives or impurities in an organicmaterial.When phosphorus is absent,barium,calcium,magnesium,sodium and potassium are converted to theirsulfates.Tin and zinc are converted to their oxides.5.2 Thisstanda
12、rdmaybeusedforresearchanddevelopment,specification acceptance and quality assurancepurposes.6.Interferences6.1 If phosphorus is present with metals,it partially orwholly remains in the sulfated ash as metal phosphates.1This test method is under the jurisdiction ofASTM Committee E37 on ThermalMeasure
13、ments and is the direct responsibility of Subcommittee E37.01 on Calo-rimetry and Mass Loss.Current edition approved Sept.1,2012.Published September 2012.Originallyapproved in 2004.Last previous edition approved in 2006 as E2403 06.DOI:10.1520/E2403-06R12.2For referenced ASTM standards,visit the AST
14、M 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
15、6.2 Sulfur and chlorides do not interfere.7.Apparatus7.1 Thermogravimetric Analyzer(TGA)The essential in-strumentation required to provide the minimum thermogravi-metric analytical capability for this standard includes:7.1.1 A thermobalance composed of:7.1.1.1 Afurnace to provide uniform controlled
16、heating of aspecimen to a constant temperature of 850C and at a constantrate of 5 to 60C/min7.1.1.2 A temperature sensor to provide an indication of thespecimen or furnace temperature to 61C.7.1.1.3 A continuously recording balance to measure thespecimen mass with a minimum capacity of 50 mg and asensitivity of 60.01 mg.7.1.1.4 A means of maintaining the specimen or containerunder atmospheric control of air at a purge flow rate of 50 to100 mL/min 6 5 mL/min.7.1.2 A temperature controller capable
