1、Designation: D3545 06 (Reapproved 2012)Standard Test Method forAlcohol Content and Purity of Acetate Esters by GasChromatography1This standard is issued under the fixed designation D3545; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method co
3、vers the determination by gaschromatography of the ester content and the correspondingalcohol content of acetate esters. This test method has beenapplied to ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and2-ethoxyethyl acetates.1.2 Water, and in some cases acetic acid, cannot be deter-mined by thi
4、s test method and must be measured by otherappropriate ASTM procedures and the results used to normal-ize the chromatographic value.1.3 For purposes of determining conformance of an ob-served or a calculated value using this test method to relevantspecifications, test result(s) shall be rounded off
5、“to the nearestunit” in the last right-hand digit used in expressing thespecification limit, in accordance with the rounding-off methodof Practice E29.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 For specific hazard i
6、nformation and guidance, see thesuppliers Material Safety Data Sheet for material listed in thisspecification.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 safet
7、y and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1364 Test Method for Water in Volatile Solvents (KarlFischer Reagent Titration Method)D1613 Test Method for Acidity in Volatile Solvents andChemical Intermediate
8、s Used in Paint, Varnish, Lacquer,and Related ProductsD2593 Test Method for Butadiene Purity and HydrocarbonImpurities by Gas ChromatographyE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE180 Practice for Determining the Precision of ASTMMethods for
9、 Analysis and Testing of Industrial and Spe-cialty Chemicals (Withdrawn 2009)3E260 Practice for Packed Column Gas Chromatography3. Summary of Test Method3.1 A representative specimen is introduced into a gas-liquid partition column. The acetate is separated from impuri-ties such as alcohols, other e
10、sters, ethers, and several uniden-tified compounds while the components are transportedthrough the column by an inert carrier gas. The separatedcomponents are measured in the effluent by a detector andrecorded as a chromatogram. The chromatogram is interpretedby applying component attenuation and de
11、tector responsefactors to the peak areas, and the relative concentrations aredetermined by relating the individual peak responses to thetotal peak response. Water and acidity are measured by TestMethods D1364 and D1613, respectively, and the results areused to normalize the values obtained by gas ch
12、romatography.4. Significance and Use4.1 This test method is useful for identifying and fordetermining the quantity of various impurities in acetate esters.4.2 Total purity of the acetate esters must be determined byuse of other appropriate ASTM procedures with this testmethod.5. Apparatus5.1 Chromat
13、ographAny gas chromatograph having eithera thermal conductivity or flame ionization detector, provided1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.35 on Solvents, Plasti
14、cizers, and Chemical Intermediates.Current edition approved June 1, 2012. Published August 2012. Originallyapproved in 1976. Last previous edition approved in 2006 as D3545 06. DOI:10.1520/D3545-06R12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Servi
15、ce at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.*A Summary of Changes section appears at the end of this standardCopyright A
16、STM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1the system has sufficient sensitivity and stability to obtain for0.01 % of the parent alcohol a recorder deflection of at least 20mm at a signal-to-noise ratio of at least 5 to 1. The specimensize
17、used in judging the sensitivity must be such that thecolumn is not overloaded, which would result in peak broad-ening, loss of resolution, shifting retention times and formationof leading peaks. Volumes of 5 L with thermal conductivityand 1 to 2 L with flame ionization detectors have been foundaccep
18、table.5.1.1 The injection port of the chromatograph must have avolume of at least 1.2 mL to provide for proper vaporization ofthe material. The use of a smaller injection port or on-columninjection has been found to cause peak broadening and tailing.5.2 ColumnA 3-m length of 6.4-mm outside diametera
19、luminum or stainless steel tubing packed with 80 to 100-meshChromosorb G-HP4,5,6that has been coated with 9.05 % DowCorning QF-16,7silicone and 0.45 % nonylphenoxypoly(ethyl-eneoxy)ethanol(CAS # 9016459), HLB = 19.0 has beenfound suitable.8Any column, packed or capillary, or anypacking material capa
20、ble of resolving one acetate ester fromany other esters and from any impurities that may be presentand giving equivalent or superior performance may be used.5.3 RecorderA recording potentiometer with a full-scaledeflection of 1 mV. Full-scale response time should be2sorless with sufficient sensitivi
21、ty and stability to meet the require-ments of 5.1.5.4 Specimen Introduction SystemAny system capable ofintroducing a representative specimen into the column. Mi-crolitre syringes have been used successfully.6. Reagents and Materials6.1 Carrier Gas, appropriate to the type of detector used.Helium or
22、hydrogen may be employed with thermal conduc-tivity detectors and nitrogen, helium, or argon with flameionization detectors. The minimum purity of the carrier gasused should be 99.95 mol %.6.1.1 If hydrogen is used special safety precautions must betaken to ensure that the system is free of leaks an
23、d that theeffluent is vented properly.6.2 Column Materials:6.2.1 Liquid Phase, Dow Corning QF-1/FS 12656,7siliconeand nonylphenoxypoly(ethyleneoxy)ethanol(CAS #9016459), HLB = 19.86.2.2 Solid Support, Chromosorb G-HP,4,6 ,580 to 100mesh size.6.2.3 SolventsMethylene chloride and acetone, reagentgrade
24、.6.2.4 Tubing MaterialStainless steel and aluminum havebeen found satisfactory for column tubing. The tubing must benonreactive with the substrate, sample, and carrier gas andmust be of uniform internal diameter.6.3 Standards for Calibration and Identification Standardsamples of all components prese
25、nt are needed for identificationby retention time and for calibration for quantitative measure-ments. Most can be obtained from chemical supply houses.7. Preparation of Apparatus7.1 Column Packing PreparationPlace 100 g of Chromo-sorb G-HP,4,6,580 to 100 mesh, in a large evaporating dish.Dissolve 10
26、 g of Dow Corning QF-1/FS 12656,7silicone in 50mL of acetone and add to the solid support. Add sufficientacetone to wet and cover the solid support. Evaporate theacetone in a fume hood with gentle stirring and under a gentlestream of nitrogen. Dissolve 0.5 g of nonylphenoxypoly(eth-ylenexy)ethanol(C
27、AS # 9016459). HLB = 19.08in 50 mL ofmethylene chloride and add it to the packing material. Addsufficient methylene chloride to wet and cover the packing.Evaporate the methylene chloride with gentle stirring under agentle stream of nitrogen. Commercially available columns orpackings, or both, are av
28、ailable from several chromatographysupply sources.7.2 Column PreparationThe method used to pack thecolumn is not critical provided that the finished columnproduces the required separation of all of the components to bedetermined. Commercially available columns or packings, orboth, are available from
29、 several chromatography supplysources.7.3 ChromatographInstall the column in the chromato-graph. Use the information in Table 1 as a guide to establish theconditions of column temperature and carrier gas flow that givethe necessary resolution of the components in the productbeing analyzed. Allow suf
30、ficient time for the instrument toreach equilibrium as indicated by a stable recorder baseline.Control the detector temperature constant to within 1C with-out thermostat cycling, which causes an uneven baseline.Adjust the carrier-gas flow rate to a constant value.NOTE 1Useful information on column p
31、reparation may be found inTest Method D2593 and Practice E260.8. Calibration and Standardization8.1 IdentificationDetermine the retention time of eachcomponent by injecting small amounts either separately or inknown mixtures. The esters should elute close to the typicalretention times given in Table
32、 1 and the chromatograms shouldclosely approximate those shown in Figs. 1-6.8.2 The area under each peak of the chromatogram isconsidered a quantitative measure of the corresponding com-pound. The relative area is proportional to concentration if thedetector responds equally to all the sample compon
33、ents. Theresponse to different components is generally significantlydifferent for both flame ionization and thermal conductivitydetectors and especially for flame ionization detectors. Differ-ence in detector response may be corrected by use of relativeresponse factors obtained by injecting and meas
34、uring the4A registered trademark of Manville Products Corp., Lompoc, CA 93436.5The sole source of supply for this material known to the committee at this timeis Manville Products Corp., Lompoc, CA 93436.6If you are aware of alternative suppliers, please provide this information toASTM International
35、Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee1which you may attend.7The sole source of supply for Silicoup QF-1/FS 1265 (1000) known to thecommittee at this time is Dow-Corning Corp., Midland, MI 48640.8Aregistered trademark of GA
36、F Corp., Dyestuff and Chemical Div., 140 W. 51stSt., New York, NY 10020.D3545 06 (2012)2FIG. 1 Typical Chromatogram of Ethyl AcetateD3545 06 (2012)3FIG. 2 Typical Chromatogram of n-Propyl AcetateD3545 06 (2012)4FIG. 3 Typical Chromatogram of Isopropyl AcetateD3545 06 (2012)5FIG. 4 Typical Chromatogr
37、am of Butyl AcetateD3545 06 (2012)6FIG. 5 Typical Chromatogram of Isobutyl AcetateD3545 06 (2012)7FIG. 6 Typical Chromatogram of 2-Ethoxyethyl AcetateD3545 06 (2012)8response to known blends. For precise and accurate determi-nation of the parent alcohol, prepare and analyze a knownblend of the aceta
38、te and alcohol in which the alcohol contentapproximates the maximum specification limit. Calculate thealcohol response factor relative to unity for the acetate. Withthermal conductivity detectors, the response factor of allimpurities other than the alcohol may be assumed to be one forobtaining the p
39、urity value. With flame ionization detectors, useexperimentally determined response factors.NOTE 2Data on thermal conductivity and flame ionization detectorresponses may be found in the literature.99. Procedure9.1 Introduce a representative specimen into the chromato-graph using sufficient material
40、to ensure a minimum of 10 %recorder deflection for a 0.1 % concentration of impurity at themost sensitive setting of the instrument.9.2 Using the same conditions as for component identifica-tion and standardization, record the peaks of all components atattenuation settings that provide optimum peak
41、heights. Mea-sure the area of all peaks (Note 3) and multiplying each area bythe appropriate attenuation factor to express the peak areas ona common basis.NOTE 3Peak areas may be determined by any method that meets theprecision in Section 12. Electronic integration of peak areas was employedto obtai
42、n the results used to establish the precision of this test method.10. Calculation10.1 Apply the appropriate detector response factor tocorrect for the difference in response to the components. Makecorrection to account for water and acidity as determined bythe ASTM procedures given in Test Methods D
43、1364, D1613,D2593, and Practices E180 and E260.10.2 Calculate the weight percent of each component asfollows:Weight % 5 A/B! 3 100 2 C! (1)where:A = corrected peak response of a component,B = sum of corrected peak responses, andC = sum of water and acidity (as acetic acid), weight %.10.3 Calculate t
44、he percent composition by dividing theindividual corrected component areas by the total correctedarea.11. Report11.1 Report the percent purity of the acetate being analyzedand the corresponding alcohol to the nearest 0.01 % absolute.Duplicate runs for ester content that agree within 0.06 %absolute a
45、re acceptable for averaging (95 % confidence level).Duplicate runs for the parent alcohol content that agree within0.02 % absolute are acceptable for averaging.12. Precision and Bias1012.1 The precision statements are based upon an interlabo-ratory study in which one operator in each of nine laborat
46、oriesanalyzed in duplicate on two days one sample of each of thefollowing esters:MeanMean AlcoholEster Purity ContentEthyl acetate 99.8 0.17n-Propyl acetate 96.9 2.7Isopropyl acetate 99.2 0.46n-Butyl acetate 98.5 0.48Isobutyl acetate 98.7 0.452-Ethoxyethyl acetate 99.1 0.51The results were analyzed
47、in accordance with Practice E180.Within-laboratory and between-laboratory standard deviationswere found to be as follows:Ester ContentWithinLaboratoriesBetweenLaboratoriesEthyl acetate 0.019 (8)A0.026 (7)An-Propyl acetate 0.032 (8) 0.138 (7)Isopropyl acetate 0.014 (7) 0.071 (6)n-Butyl acetate 0.029
48、(6) 0.056 (5)Isobutyl acetate 0.042 (8) 0.213 (7)2-Ethoxyethyl acetate 0.014 (8) 0.142 (7)ADegrees of freedom are shown in parentheses.Parent Alcohol ContentWithinLaboratoriesBetweenLaboratoriesEthyl acetate 0.004 (7)A0.028 (6)An-Propyl acetate 0.015 (8) 0.062 (7)Isopropyl acetate 0.003 (8) 0.009 (7
49、)Parent Alcohol ContentWithinLaboratoriesBetweenLaboratoriesn-Butyl acetate 0.004 (7) 0.011 (6)Isobutyl acetate 0.014 (8) 0.017 (7)2-Ethoxyethyl acetate 0.005 (8) 0.015 (7)ADegrees of freedom are shown in parentheses.Based upon these standard deviations, the following criteriashould be used for judging the acceptability of results at the95 % confidence level.12.1.1 RepeatabilityTwo results, each the mean of dupli-cates, obtained by the same operator on different days shouldbe considered suspect if they differ by more than the following:Ester co