1、Designation: E611 08 (Reapproved 2015)1Standard Test Methods forLow Concentrations of Diethlyene Glycol in Ethylene Glycolby Gas Chromatography1This standard is issued under the fixed designation E611; the number immediately following the designation indicates the year oforiginal adoption or, in the
2、 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.1NOTEEditorial change was made in Subsection 1.3 in May 2016.1. Scope*1.1 These test methods are in
3、tended primarily for theanalysis of mixtures of ethylene and diethylene glycols inwhich the diethylene glycol concentration is 0.1 % or less.Both test methods should be applicable to higher concentra-tions of diethylene glycol, but precision and bias estimateshave been obtained only for 0.05 to 0.1
4、% diethylene glycol.NOTE 1Test Methods E202 describe another gas chromatographic testmethod applicable to mixtures of ethylene, diethylene, and triethyleneglycols and mixtures of propylene, dipropylene, and tripropylene glycolsin which one of the glycols is the principal component and the other twoa
5、re present in concentrations of 0.1 to 1 % each.NOTE 2Test Method E2409 describes another gas chromatographictest method for the determination of glycol impurities in mono-, di-, tri-and tetraethylene glycol (MEG, DEG, TEG and TeEG) in the range of 5to 3000 g/g.1.2 The two test methods are given as
6、follows:SectionsTest Method ANonderivative Method 5 to 13Test Method BDerivative Method 14 to 221.3 Review the current Safety Data Sheets (SDS) for de-tailed information concerning toxicity, first aid procedures, andsafety precautions for chemicals used in this standard.1.4 The values stated in SI u
7、nits are to be regarded asstandard. No other units of measurement are included in thisstandard with the exception of foot-pound units for apparatusdescriptions.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the use
8、r of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For a specificwarning statement, see 15.1.5.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterE180 Practice for Determining
9、the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty Chemicals (Withdrawn 2009)3E202 Test Methods for Analysis of Ethylene Glycols andPropylene GlycolsE2409 Test Method for Glycol Impurities in Mono-, Di-, Tri-and Tetraethylene Glycol and in Mono- and DipropyleneGlycol(
10、Gas Chromatographic Method)2.2 Other Document:Manufacturers instruction manuals of gas chromatograph3. Significance and Use3.1 Either test method may be used to determine theconcentrations of diethylene glycol in ethylene glycol. Theconcentrations of the components are obtained by a normal-ization t
11、echnique, based on the assumption that all componentsare eluted under the conditions used. If all components shouldnot be eluted, the calculated concentrations will be erroneouslyhigh, with the major component showing the most significantabsolute error. Since water is not detected by these procedure
12、s,the results are on a water-free basis. Water may be determinedin accordance with the applicable sections of Test MethodsE202 and the gas chromatographic results corrected for thewater concentration.3.2 Both test methods are currently in industrial use. TestMethodAis the simpler of the two test met
13、hods because it doesnot require the preparation of derivatives prior to gas chro-matographic analysis. The results obtained by Test Method Aare slightly more accurate than those obtained by Test MethodB. With respect to precision there is no significant differencebetween the two test methods. Test M
14、ethod B has been1These test methods are under the jurisdiction of ASTM Committee E15 onIndustrial and Specialty Chemicalsand are the direct responsibility of SubcommitteeE15.02 on Product Standards.Current edition approved June 1, 2015. Published June 2015. Originallyapproved in 1977. Last previous
15、edition approved in 2008 as E61108. DOI:10.1520/E0611-08R15E01.2For 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 websit
16、e.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 ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1reported to be suitable also for th
17、e analysis of a wide variety ofglycol ethers, but this use is beyond the scope of this standard.4. Purity of Reagents4.1 Reagent grade chemicals shall be used in all tests.Unless otherwise indicated, it is intended that all reagents shallconform to the specifications of the Committee on AnalyticalRe
18、agents of the American Chemical Society, where suchspecifications are available.4Other grades may be used, pro-vided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.4.2 Unless otherwise indicated, references
19、to water shall beunderstood to mean Type II or III reagent water conforming toSpecification D1193.TEST METHOD ANONDERIVATIVE METHOD5. Summary of Test Method5.1 The sample is injected into a gas chromatographiccolumn. The components are separated as they pass throughthe column with helium carrier gas
20、, their presence in theeffluent is detected by a flame ionization detector, and recordedas a chromatogram. The areas under the peaks due to thesample components are corrected by applying appropriatecalibration factors to obtain the composition of the sample ona weight percentage basis.6. Apparatus6.
21、1 Gas Chromatographic Instrument having the followingminimal characteristics (see Table 1).6.1.1 Sample Injection Port, with heater characteristicsnecessary for operation at 210C.6.1.2 Column Oven, capable of isothermal operation at168C.6.1.3 Detector, of conventional flame ionization type, ca-pable
22、 of operating at 168C. A conventional thermal conduc-tivity detector can be used, but sensitivity will be reduced andwater may be detected as a peak eluting with the pressure peakdue to sample injection, depending upon the concentration ofwater. The precision and bias statements in Section 13 are fo
23、rflame ionization detectors.6.1.4 Recorder, 0 to 1-mV range, that 1-s full scale deflec-tion with a chart speed of approximately 1.3 cm/min or otherconvenient speed that will produce a satisfactorychromatogram, and an attenuator switch to change the recorderrange as required to keep the chromatogram
24、 on scale.NOTE 3On instruments using electronic integration the attenuationfeature is not required.6.1.5 Column, 50 in. long,316 in. in outside diameter with awall thickness of 0.030 in. for copper or 0.020 in. for stainlesssteel construction; packed with 10 % polyethylene glycol onorange calcinated
25、 diatomite with dimethyldichlorosilane,DMCS, 60/80 mesh.6.1.6 Microsyringe, 10-L capacity.6.1.7 Copper or Stainless Steel Tubing,316 in. in outsidediameter with a wall thickness of 0.030 in. for copper or 0.020in. for stainless steel.NOTE 4The copper tubing should be sealed, refrigeration grade. If
26、theseal has been broken, clean the copper tubing with an acetone wash anddry with nitrogen before filling. Stainless steel tubing should be pre-washed with successive volumes of 10 % HCl, distilled water, acetone,methylene chloride, and dried with nitrogen.7. Reagents and Materials7.1 Air, compresse
27、d.7.2 Orange Calcinated Diatomite withDimethyldichlorosilane, 60/80 mesh.7.3 Ethylene Glycol and Diethylene GlycolSee Section 9for purity requirements.7.4 Helium (He).7.5 Hydrogen (H2).7.6 Methylene Chloride (Dichloromethane) (CH2Cl2).7.7 Polyethylene Glycol, 20 000 molecular weight.4Reagent Chemica
28、ls, American Chemical Society Specifications, Am. ChemicalSoc., Washington, DC. For suggestions on the testing of reagents not listed by theAmerican Chemical Society, see Analar Standards for Laboratory Chemicals, BDHLtd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary
29、, U.S. Pharmacopeial Convention, Inc. (USP), Rockville, MD.TABLE 1 Instrument Parameters, Method ANonderivativeInstrument Varian Aerograph. Model 204, equipped with flame ionization detectorsAStrip-chart recorder 0-1 mV rangeChart speed12 in. (12.7 mm)/minColumn 50 in. (1270 mm) of316-in. (4.8-mm) o
30、utside diameter copper orstainless steel tubing packed with 10 % polyethylene glycol.20 000 molecular weight, on Chromosorb G, DMCS, 60/80 meshColumn temperature 168CCarrier gas helium at 100 mL/minHydrogen flow rate 40 mL/minAir flow rate 400 mL/minInjection port temperature 210CDetector block temp
31、erature 168CSample size 2LInjection time 28 sAThe parameters in this table apply to a Varian Aerograph, Model 204, manufactured by Varian Div., 611 Hansen Way, Palo Alto, CA 94303. Any similar instrument maybe used for this method with appropriate modifications of the parameters.E611 08 (2015)128. P
32、reparation of Chromatographic Column8.1 Dissolve 20 g of the polyethylene glycol in approxi-mately 200 mL of CH2Cl2with gentle warming to aid solution.Add 180 g of orange calcinated diatamite withdimethyldichlorosilane, DMCS, and sufficient CH2Cl2to forma slurry, and mix well, making certain that al
33、l particles arewetted. Evaporate the CH2Cl2by heating gently over a steambath in a fume hood until the mixture is dry. Frequent stirringof the slurry during the drying operation is necessary to obtaina uniform coating. The use of a vacuum rotary evaporator willshorten the time required for drying.8.
34、2 Screen the dried packing through a 50-mesh (300-mscreen opening) and an 80-mesh (180-m screen opening)screen to remove any lumps and fines. Fill a 127-cm section1.4-cm outside diameter copper or stainless steel tubing withthe screened packing retained on the 80-mesh screen. Gentlyvibrate the tubin
35、g during packing to ensure uniform packing.Use borosilicate glass wool for plugs in the ends of the column.Columns packed using vacuum or by blowing the packing intothe tubing are generally unsatisfactory.8.3 Condition the column prior to use by placing the columnin the chromatograph in accordance w
36、ith 10.1, but do notconnect the column to the detector. Pass helium through thecolumn at 100 mL/min during the conditioning.9. Calibration Factors9.1 In order to obtain the composition of the sample in termsof mass percent, multiply the areas associated with the com-ponents by an appropriate calibra
37、tion factor. These factors areobtained from mixtures of known composition, and should bedetermined for each apparatus. The calibration factors may beobtained using standards prepared from “hearts cuts” from thedistillation of each of the glycols, or from commercial gradesof each glycol as described
38、in the following test methods. Forhighest accuracy, use glycols obtained from “hearts cuts.”Check the calibration factors periodically or whenever there isevidence of a change in the column or instrument.9.2 Calibration Method 1:9.2.1 Purify the commercial grade of each glycol needed bycareful fract
39、ionation in glass at reduced pressure, discardingthe first 30 % and retaining the next 30 % as the “hearts cuts.”Analyze these fractions as described in Section 10 to be surethey are free of other homologues of the glycol.9.2.2 Prepare a standard mixture of these glycols whosecomposition approximate
40、s that of the glycol to be analyzed.The composition of the standard should be known to thenearest 0.001 %. Correct the composition for any water presentusing the equation in 11.2.4. Determine the water content asdescribed in the applicable section of Test Methods E202.9.2.3 Obtain at least two chrom
41、atograms of the standardmixture as described in Section 10 and calculate the averagearea percent for each of the glycols present in accordance with11.2.1. Do not include any areas associated with the pressurepeak in calculating the area percentages. Using the weightpercentages in the standard mixtur
42、e and the average areapercentages, calculate the factor for diethylene glycol asdescribed in 11.1.1.Assume a calibration factor of unity for theethylene glycol in the base ethylene glycol standard mixture.9.3 Calibration Method 2:9.3.1 For routine analyses, high-purity, commercial gradesof each glyc
43、ol may be used. If the gas chromatographicanalysis as described in Section 10 indicates that the concen-tration of the ethylene glycol in the diethylene glycol to beadded to the base ethylene glycol in the standard mixture doesnot exceed 0.2 area %, the concentration of the impurity isinsignificant
44、at the concentration levels included in the scope ofthis test method. The base ethylene glycol should contain lessthan 0.05 area % diethylene glycol.9.3.2 Prepare a standard mixture of the glycols whosecomposition approximates that of the glycol to be analyzed.The composition of the standard mixture
45、 should be known tothe nearest 0.001 %. Correct the composition for any waterpresent using the equation in 11.2.4. Determine the watercontent as described in the applicable section of Test MethodsE202. If the concentrations of the ethylene glycol in thediethylene glycol added to the base ethylene gl
46、ycol in thestandard mixture does not exceed 0.2 area %, the concentrationof the impurity is insignificant at the concentration levelsincluded in the scope of this method. The base ethylene glycolshould contain less than 0.1 area % diethylene glycol.9.3.3 Obtain at least two chromatograms of the stan
47、dardmixture and of the base ethylene glycol in accordance with10.2 and calculate the average area percent for each of theglycols present in accordance with 11.2.1. Do not include anyareas associated with the pressure peak in calculating the areapercentages. Using the mass percent of diethylene glyco
48、l addedto the ethylene glycol and the average area percentages for theglycols calculate the calibration factor for the diethylene glycolin accordance with 11.1.2. Assume the calibration factor ofunity for the ethylene glycol in the base ethylene glycol and thestandard mixture.10. Procedure10.1 Mount
49、 the column in the chromatograph, and adjustthe operating conditions in accordance with the parametersgiven in Table 1 (see Note 5). Allow sufficient time for theinstrument to reach equilibrium as indicated by a stable baseline on the chart at the maximum sensitivity setting to be used.NOTE 5The instrument parameters given in Table 1 were developedfor the indicated instrument. The use of other instruments will probablyrequire some adjustment of column temperature, helium flow rate, etc., toachieve retention times similar to those in Table 2. Adjust the p
