1、Designation: D 3340 98 (Reapproved 2003)An American National StandardStandard Test Method forLithium and Sodium in Lubricating Greases by FlamePhotometer1This standard is issued under the fixed designation D 3340; the number immediately following the designation indicates the year oforiginal adoptio
2、n or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers determination of the lithium andsodium content of
3、lubricating greases by means of a flamephotometer.1.2 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 r
4、egulatory limitations prior to use.1.3 The preferred units are mass % and accepted SI units.The values given in parentheses are for information only.2. Referenced Documents2.1 ASTM Standards:D 1193 Specification for Reagent Water23. Summary of Test Method3.1 The sulfated ash of the grease is extract
5、ed with waterand the lithium and sodium content of the resulting solution isdetermined by means of a suitable flame photometer.4. Significance and Use4.1 Lubricating greases can contain the lithium soap ofhydroxy stearic acid or the sodium soap of various fatty acidsas thickeners. The determination
6、of total lithium or totalsodium is a measure of the amount of thickener in the grease.5. Apparatus5.1 Flame Photometer, suitably equipped to determinelithium and sodium over a range from 0 to 15 mg/L lithium andfrom 0 to 5 mg/L sodium.6. Reagents6.1 Purity of ReagentsReagent grade chemicals shall be
7、used in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused, provided it is first ascertained that the rea
8、gent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.6.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water as definedby Type II of Specification D 1193.6.3 Lithium Sulfate, Stock Solution1.188 g
9、of lithiumsulfate dried to constant weight at 180C (356F), is dissolvedin water and made up to 1 L. This will contain 150 mg/Llithium.6.4 Sodium Sulfate, Stock Solution0.1544 g of sodiumsulfate, dried to constant weight at 105C (221F), is dissolvedin water and made up to 1 L. This will contain 50 mg
10、/L sodium.6.5 Sulfuric Acid (rel. den. 1.84)Concentrated sulfuricacid (H2SO4).7. Sampling7.1 A homogeneous sample shall be obtained to ensurequantitative analytical results.8. Procedure8.1 Weigh to the nearest 1 mg approximately1gofthegrease into a platinum dish or crucible. Heat the dish until thes
11、ample can be ignited with a flame. Maintain at such atemperature that the sample burns at a uniform and moderaterate, leaving only ash and carbon when the burning ceases.8.2 Cool the dish and completely moisten the residue by thedropwise addition of concentrated sulfuric acid. Heat the dishat a low
12、temperature, taking care to avoid spattering of thecontents, and continue heating until fumes are no longerevolved. Place the dish in a furnace at 550 6 25C (1022 645F) and continue heating until the oxidation of the carbon ispractically complete.1This test method is under the jurisdiction of ASTM C
13、ommittee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.03 on Elemental Analysis.Current edition approved May 10, 2003. Published July 2003. Originallyapproved in 1974. Last previous edition approved in 1998 as D 334098.2Annual Book of ASTM Standards, Vol
14、 11.01.3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pha
15、rmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.8.3 Cool and repeat 8.2 to complete the sulfation.8.4 Extract the sulfated ash with hot distill
16、ed water andtransfer the aqueous extract, filtering if necessary, to a 100-mLvolumetric flask. Allow to cool and make up to the mark withdistilled water.8.5 Prepare the following fresh calibration standards byappropriate dilution of the stock solutions:8.5.1 Lithium SulfateSolutions containing 0, 3,
17、 6, 9, 12and 15 mg/L lithium.8.5.2 Sodium SulfateSolutions containing 0, 1, 2, 3, 4, and5 mg/L sodium.8.6 Obtain the flame photometer readings for each calibra-tion standard and prepare curves relating concentration tophotometer reading.8.7 Obtain readings for the extract derived from 8.4 anddetermi
18、ne the lithium and sodium contents from the calibrationcurves.NOTE 1Further dilution may be necessary.9. Calculation and Report9.1 Calculate the lithium content of the grease as follows:Lithium, mass % 5 X/100 W (1)where:X = lithium content of the water extract, mg/L lithium (see8.7), andW = mass of
19、 the grease taken, g.Modify the formula if further dilution of the water extractwas necessary, for example, if further dilution of 50 mL to 200mL was made, then:Lithium, mass % 5 X!200!/100 W!50! (2)9.2 Report the result as lithium content.9.3 Calculate the sodium content of the grease as follows:So
20、dium, mass % 5 Y/100 W (3)where:Y = sodium content of the water extract in mg/L sodium(see 8.7), andW = mass of the grease taken, g.Modify the formula if further dilution of the water extractwas necessary as in 9.1.9.4 Report the result as sodium content.10. Precision and BiasNOTE 2The precision dat
21、a were derived within the IP. The methodhas not as yet been cooperatively tested by ASTM.10.1 The precision of this test method as determined bystatistical examination of interlaboratory results is as follows:10.1.1 Lithium:10.1.1.1 RepeatabilityThe difference between two testresults, obtained by th
22、e same operator with the same apparatusunder constant operating conditions on identical test material,would in the long run, in the normal and correct operation ofthe test method, exceed the following values only in one casein twenty:10.1.1.2 Lithium 0.014(x)2/5.10.1.1.3 Sodium 0.029(x)2/5.10.1.2 Re
23、producibilityThe difference between two singleand independent results obtained by different operators work-ing in different laboratories on identical test material would, inthe long run, in the normal and correct operation of the testmethod, exceed the following values only in one case intwenty:10.1
24、.2.1 Lithium 0.075(x)2/5.10.1.2.2 Sodium 0.166(x)2/5, where x is the lower of twovalues.NOTE 3The applicable range of concentrations are 0 to 0.4 %mass/mass lithium and 0 to 8 % mass/mass sodium.NOTE 4These precision values have been obtained by statisticalexamination of interlaboratory test results
25、 by the Institute of Petroleumand were first published in 1966. They were obtained from the test resultsfrom nine laboratories using the following instruments:No. ofLaborato-ries6 “EEL” Flame Photometer.2 SP 900 Unicam (modified).1 H 700 Uvispek spectrophotometer(modified)10.2 BiasThe bias of this t
26、est method cannot be deter-mined because no suitable reference material is available.NOTE 5The values of these precision estimates for selected values ofx are set out in the Table 1.11. Keywords11.1 flame photometer; lithium content; lubricating grease;sodium content; thickenerTABLE 1 Precision Valu
27、es for Lithium and Sodium (Mass %)Lithium,xRepeatability0.014(x)2/5Reproducibility0.075(x)2/50.01 0.002 0.0110.05 0.004 0.0220.1 0.005 0.0290.2 0.007 0.0390.3 0.008 0.0460.4 0.009 0.052Sodium,xRepeatability0.029(x)2/5Reproducibility0.166(x)2/50.01 0.004 0.0260.05 0.008 0.0500.1 0.011 0.0660.2 0.015
28、0.0870.3 0.017 0.1020.4 0.020 0.1150.5 0.022 0.1250.6 0.023 0.1350.7 0.025 0.1430.8 0.026 0.151D 3340 98 (2003)2ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advis
29、ed that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either r
30、eapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If
31、you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 3340 98 (2003)3
