1、Designation: E 346 99 (Reapproved 2003)e1Standard Test Methods forAnalysis of Methanol1This standard is issued under the fixed designation E 346; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number i
2、n parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.e1NOTE792 mg/mL was corrected editorially to 792 mg/L in Section 61.1.1 i
3、n February 2006.1. Scope1.1 These test methods cover chemical and physical tests formeasuring the quality of methanol and appear in the followingorder:SectionsPurity of Reagents 4Safety Precautions 5Sampling 6Acidity 7 to 9Carbonizables 10 to 18Color 19 to 21Distillation Range 22 to 24Permanganate T
4、ime 25 to 27Specific Gravity 28 to 30Water 31to33Water Miscibility 34 to 37Ethanol 37 to 47Acetone 48 to 55Trimethylamine 56 to 651.2 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 establis
5、h appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Specific hazardsstatements are given in Sections 5 and 15 and in 16.1, 16.4, and52.2.2.2. Referenced Documents2.1 ASTM Standards:2D 891 Test Methods for Specific Gravity, Apparent, ofL
6、iquid Industrial ChemicalsD 1078 Test Method for Distillation Range of VolatileOrganic LiquidsD 1193 Specification for Reagent WaterF 1209 Guide for Ecological Considerations for the Use ofOilspill Dispersants in Freshwater and Other Inland Envi-ronments, Ponds and SloughsD 1363 Test Method for Perm
7、anganate Time of Acetoneand MethanolD 1613 Test Method for Acidity in Volatile Solvents andChemical Intermediates Used in Paint, Varnish, Lacquer,and Related ProductsD 1722 Test Method for Water Miscibility of Water-SolubleSolventsE 180 Practice for Determining the Precision of ASTMMethods for Analy
8、sis and Testing of Industrial and Spe-cialty ChemicalsE 203 Test Method for Water Using Volumetric Karl FischerTitrationE 300 Practice for Sampling Industrial ChemicalsE 1140 Practice for Testing Nitrogen/Phosphorus Thermi-onic Ionization Detectors for Use In Gas Chromatography3. Significance and Us
9、e3.1 These test methods are suitable for manufacturing con-trol and for determining compliance with specification limitsfor the properties designated by the test methods. For those testmethods that use the procedure given in other ASTM methods,those test methods should be consulted for additional in
10、forma-tion on the significance, use, and possible interferences.4. Purity of Reagents4.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of th
11、e American Chemical Society,where such specifications are available.3Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.1These test methods are under the jurisdiction of ASTM Co
12、mmittee E15 onIndustrial and Specialty Chemicals and are the direct responsibility of Subcommit-tee E15.02 on Product Standards.Current edition approved March 10, 1999. Published May 1999. Originallypublished as E 346 68 T. Last previous edition E 346 94.2For referenced ASTM standards, visit the AST
13、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.3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. Fo
14、r 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 Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM Interna
15、tional, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2 Unless otherwise indicated, references to water shall beunderstood to mean Type II or III reagent water conforming toSpecification D 1193. It is essential that the reagent water befree of ammonia when use
16、d in the method for acetone.5. Hazards5.1 Methanol is toxic both as a liquid and as a vapor, and isdangerous if not properly handled. Avoid any skin contact.Clothing contaminated with methanol should be removedimmediately. Any body exposure to methanol requires imme-diate medical attention.5.2 Metha
17、nol is flammable and its vapor is explosive in therange from 6.0 to 36.5 volume % in air. Any spills should beflushed away promptly with water.6. Sampling6.1 Sampling is not within the scope of these test methods.It should be understood, however, that reference to a “sample”means a representative po
18、rtion of methanol contained in asingle container submitted for test. The sample submittedshould be sufficient to make all tests without reuse of anyfraction. For details of sampling methanol, refer to PracticeE 300.ACIDITY7. Procedure7.1 Determine the acidity of the methanol as acetic acidusing the
19、titration method as described in Test Method D 1613.8. Report8.1 For concentrations of acetic acid at the 0.0010 % level,report the results to the nearest 0.0001 weight %. For concen-trations at the 0.010 % level, report the results to the nearest0.001 weight %.9. Precision and Bias9.1 PrecisionThe
20、following criteria should be used forjudging the acceptability of results (Note 1):9.1.1 Repeatability (Single Analyst)The standard devia-tion for a single determination has been estimated to be theabsolute percentage value in Table 1 at the indicated degrees offreedom (df). The 95 % limit for the d
21、ifference between twosuch runs is the absolute percentage value in the table.9.1.2 Laboratory Precision (Within-Lab Between-Days)The standard deviation of results (each the average of dupli-cates), obtained by the same analyst on different days, has beenestimated to be the absolute percentage value
22、in Table 1 at theindicated degrees of freedom. The 95 % limit for the differencebetween two such averages is the absolute percentage value inthe table.9.1.3 Reproducibility (Multilaboratory)The standard de-viation of results (each the average of duplicates), obtained byanalysts in different laborato
23、ries, has been estimated to be theabsolute percentage value in Table 1 at the indicated degrees offreedom. The 95 % limit for the difference between two suchaverages is the absolute percentage value in the table.NOTE 1The above precision estimates are based on an interlaboratorystudy performed on tw
24、o samples of methanol containing approximately0.0010 and 0.01 % acetic acid. A total of nine laboratories cooperated inthe studies in which duplicate determinations were performed on each oftwo days. Practice E 180 was used in developing these precision esti-mates.9.2 BiasThe bias of this test metho
25、d has not been deter-mined due to the unavailability of suitable reference materials.CARBONIZABLES10. Scope10.1 This test method describes a procedure for detectingthe presence of impurities in methanol that carbonize or darkenin the presence of concentrated sulfuric acid. The test methodis applicab
26、le to methanol having a carbonizables content in therange from 0 to 70 on the platinum-cobalt scale (see TestMethod D 1209).11. Summary of Test Method11.1 Methanol is mixed with a known volume of concen-trated sulfuric acid under controlled conditions. The colorformed by the action of the acid on th
27、e carbonizable impuritiesin the methanol is estimated by comparison of the test mixturewith platinum-cobalt color standards.12. Significance and Use12.1 Because this test is designed to measure low concen-trations of impurities that carbonize or darken in the presenceof concentrated sulfuric acid, e
28、rroneously high results may beobtained if all glassware is not cleaned as described in theprocedure.13. Apparatus13.1 Erlenmeyer Flask, 125-mL borosilicate glass.13.2 Nessler Tubes, 50-mL high form, matched.13.3 Ring Stand.13.4 Buret, 25-mL, with TFE-fluorocarbon stopcock.NOTE 2A 25-mL automatic bur
29、et graduated in 0.1-mL incrementsprovides a safe convenient way of dispensing the sulfuric acid and protectsthe acid from dust and other contamination.13.5 Electric Stirrer and Bar.14. Reagents14.1 Sulfuric AcidConcentrated sulfuric acid (sp gr 1.84).TABLE 1 Acidity Precision Values, % Acetic AcidLe
30、vel,%Repeatability Laboratory Precision Within-Lab, Between-Days ReproducibilityStandardDeviationDegrees ofFreedom95 % LimitStandardDeviationDegrees ofFreedom95 % LimitStandardDeviationDegrees ofFreedom95 % Limit0.0010 0.000067 18 0.0002 0.000065 18 0.0002 0.00024 8 0.000070.010 0.00034 18 0.001 0.0
31、00437 18 0.001 0.00061 8 0.002E 346 99 (2003)e1214.2 Platinum-Cobalt Stock Solution and Color Standards,made in accordance with Test Method D 1209.15. Hazards15.1 Concentrated sulfuric acid is corrosive; contact withthe body is to be avoided at all times. Use proper protectiveequipment, including ad
32、equate eye protection. If the eyes areaffected or if a burn results, obtain immediate medical atten-tion.16. Procedure16.1 All glass apparatus used for this test must be kept freeof materials which produce color with sulfuric acid. Clean allglassware in a dichromate-sulfuric acid cleaning solutionfo
33、llowed by rinsings with tap water and reagent water. Drywith clean air or rinse with methanol that is known to give littleor no color with sulfuric acid. (WarningDo not use acetoneto dry apparatus.)16.2 Transfer 50 mL of the proper platinum-cobalt colorstandard into one of the matched 50-mL Nessler
34、tubes.16.3 Pipet 30 mL of the sample into a 125-mL Erlenmeyerflask.16.4 Add, at a uniform rate, 25 mL of H2SO4to the samplewhile stirring constantly using an electric stirrer and stirringbar. The total time of the acid addition shall be 5 min 6 30 s.(WarningDo not cool the mixture.)16.5 Allow the mi
35、xture to stand for 15 min 6 30 s at roomtemperature, pour the mixture from the flask into a 50-mLNessler tube and compare the color of the sample to the properplatinum-cobalt standard by looking down through the longi-tudinal axis of the tubes upon a white or mirrored surface atsuch an angle that li
36、ght is reflected through the column ofliquid. Hold the tubes at some convenient height 50 to 150 mm(2 to 6 in.) from the surface.17. Report17.1 According to the type of specification used, this testcan be made to give specific color readings or be simply a go,no-go test.17.2 When specific color read
37、ings are required, report theplatinum-cobalt color to the nearest 5 units. Averages ofduplicate determinations should be reported to the nearest 2.5units.18. Precision and Bias18.1 PrecisionThe following criteria should be used forjudging the acceptability of results (see Note 3):18.1.1 Repeatabilit
38、y (Single Analyst)The standard devia-tion for a single determination has been estimated to be 1.7units at 21 df. The 95 % limit for the difference between twosuch runs is 5 units.18.1.2 Laboratory Precision (Within-Lab Between-Days)The standard deviation of results (each the average of dupli-cates),
39、 obtained by the same analyst on different days, has beenestimated to be the value in Table 2 at the indicated degrees offreedom. The 95 % limit for the difference between two suchaverages is the value in the table.18.1.3 Reproducibility (Multilaboratory)The standard de-viation of results (each the
40、average of duplicates), obtained byanalysts in different laboratories, has been estimated to be thevalue shown in Table 2 at the indicated degrees of freedom.The 95 % limit for the difference between two such averages isthe value in the table.NOTE 3The precision estimates in Table 2 are based on an
41、interlabo-ratory study performed on three samples at the color levels listed. Oneanalyst in each of seven laboratories performed duplicate measurementson each of two days. Practice E 180 was used in developing theseprecision estimates.18.2 BiasThe bias of this test method has not beendetermined due
42、to the unavailability of suitable referencematerials.COLOR19. Procedure19.1 Determine the color of the methanol as described inTest Method D 1209.20. Report20.1 Estimate and report the color of the methanol to thenearest 1 Pt-Co unit.21. Precision and Bias21.1 PrecisionThe following criteria should
43、be used forjudging the acceptability of results (see Note 4):21.1.1 Repeatability (Single Analyst)The standard devia-tion for a single determination has been estimated to be 0.7units at 36 df. The 95 % limit for the difference between twosuch runs is 2 units.21.1.2 Laboratory Precision (Within-Lab B
44、etween-Days)The standard deviation of results (each the average of dupli-cates), obtained by the same analyst on different days, has beenestimated to be the value in Table 3 at the indicated degrees offreedom. The 95 % limit for the difference between two suchaverages is the value in the table.21.1.
45、3 Reproducibility (Multilaboratory)The standard de-viation of results (each the average of duplicates), obtained byanalysts in different laboratories, has been estimated to be thevalue shown in Table 3 at the indicated degrees of freedom.The 95 % limit for the difference between two such averages is
46、the value in the table.TABLE 2 Carbonizables Precision Values, Pt-Co UnitsPt-Co LevelLaboratory Precision Within-Lab, Between-Days ReproducibilityStandard DeviationDegrees ofFreedom95 % Limit Standard DeviationDegrees ofFreedom95 % Limit5113326 515 1 13 3 3 6 1060 1 13 3 5 6 15E 346 99 (2003)e13NOTE
47、 4The above precision estimates are based on an interlaboratorystudy performed on two samples of methanol having Pt-Co color values of0 and 10 respectively. One analyst in each of eight laboratories performedduplicate measurements on each of two days. Practice E 180 was used indeveloping these preci
48、sion estimates.21.2 BiasThe bias of this test method has not beendetermined due to the unavailability of suitable referencematerials.DISTILLATION RANGE22. Procedure22.1 Determine the distillation range of the methanol asdescribed in Test Method D 1078. ASTM Solvents DistillationThermometer 39C (rang
49、e 48 to 102C with 0.2 subdivisions)should be used.22.2 Use a K value of 0.033 for calculating the barometriccorrection to be applied to each corrected thermometer readingfor the following volumes of distillate: 1st drop, 5, 50, 95 mLand dry point. The dry point is defined as the temperature at theinstant the last drop of methanol evaporates from the lowestpoint in the distillation flask disregarding any liquid clinging tothe side of the flask. If the boiling range does not exceed 2C,a simpler correction is permissible, such as by filling thecondenser ba
