1、Designation: E411 17E411 17aStandard Test Method forTrace Quantities of Carbonyl Compounds with 2,4-Dinitrophenylhydrazine1This standard is issued under the fixed designation E411; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, th
2、e 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.1. Scope*1.1 This test method covers the determination of total carbonyl in the range from 0.5 to 50 g calculated as CO.
3、1.2 This test method is intended to be general and does not include steps for sample preparation.1.3 Acetals that hydrolyze under the conditions of the test are also determined.1.4 Carbonyl derivatives such as acetals and imines that are easily hydrolyzed may be determined by an alternative procedur
4、e.1.5 The developed color is not stable and must be measured within a specified period.NOTE 1Other test methods for the determination of traces of carbonyl compounds are given in Test Methods D1089, D1612, D2119, and D2191.1.6 Review the current appropriate Safety Data Sheets (SDS) for detailed info
5、rmation concerning toxicity, first aid procedures,and safety precautions.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its
6、 use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. Specific hazards statements are given in Section 7 and Section 8.1.9 This international standard was developed in acc
7、ordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM
8、Standards:2D1089 Method of Test for Carbonyl Content of Butadiene (Withdrawn 1984)3D1193 Specification for Reagent WaterD1612 Test Method for Acetone in Methanol (Withdrawn 2011)3D2119 Test Method for Aldehydes in Styrene MonomerD2191 Test Method for Acetaldehyde Content of Vinyl AcetateD6809 Guide
9、for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related MaterialsE60 Practice for Analysis of Metals, Ores, and Related Materials by SpectrophotometryE180 Practice for Determining the Precision of ASTM Methods for Analysis and Testing of Industrial and Specialty Ch
10、emicals(Withdrawn 2009)3E300 Practice for Sampling Industrial Chemicals3. Summary of Test Method3.1 The sample containing traces of carbonyl compounds is reacted with an acidic solution of 2,4-dinitrophenylhydrazine toform the hydrazone which, upon reaction with potassium hydroxide, forms a wine-red
11、 color, presumably due to a resonating1 This test method is under the jurisdiction of ASTM Committee D16 on Aromatic, Industrial, Specialty and Related Chemicals and is the direct responsibility ofSubcommittee D16.15 on Industrial and Specialty General Standards.Current edition approved April 15, 20
12、17July 1, 2017. Published April 2017July 2017. Originally approved in 1970. Last previous edition approved in 20122017 asE411 12.E411 17. DOI: 10.1520/E0411-17.10.1520/E0411-17a.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. F
13、or Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standar
14、d an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM i
15、s to be considered the official document.*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 States1quinoidal ion. The intensity of the red color, which is a function of the carbon
16、yl concentration, is determined photometrically andthe amount of carbonyl is read directly from a previously prepared calibration curve. This test method is based upon the work ofLappin and Clark.44. Significance and Use4.1 This test method is applicable to the determination of trace amounts of alde
17、hydes and ketones in aqueous solutions and awide variety of organic solvents.5. Interferences5.1 This test method has been found to be relatively free from interferences. It is necessary, however, to test a sample to ensurethat it does not interfere.5.2 Carbonyl compounds containing conjugated unsat
18、uration interfere by absorbing at a different wavelength than othercarbonyl compounds.5.3 Acetals that are only partially hydrolyzed under the conditions of the test will interfere. A higher reaction temperature isrequired to effect complete hydrolysis.5.4 Certain carbonyl compounds such as diisobut
19、yl ketone have been found to undergo incomplete reactions and thus give lowresults. These compounds may be determined if a suitable calibration is made using the compound in question.5.5 Because of the extreme sensitivity of this test method, it is necessary to perform the test in a room from which
20、acetone orother carbonyl compound vapors are excluded.6. Apparatus6.1 Spectrophotometer or Photometer, capable of measuring light absorption at 480 nm and holding a 1-cm cell.NOTE 2If a filter photometer is used, a narrow band filter having its maximum transmission at approximately 480 nm should be
21、used. A discussionof photometers and photometric practice is given in Practice E60.6.2 Absorption Cells, 1-cm.6.3 All glassware must be cleaned before use. Rinse thoroughly with water and finally with methanol. Do not use acetone todry the glassware.NOTE 3The precision and bias reported in this test
22、 method were determined using chromic acid cleaning solution to clean the glassware. The effecton precision and bias of using other cleaning materials has not been determined.7. Reagents7.1 Purity of ReagentsUnless otherwise indicated, it is intended that all reagents shall conform to the specificat
23、ions of theCommittee on Analytical Reagents of the American Chemical Society, where such specifications are available.5 Other grades maybe used, provided it is first ascertained that the reagent is of sufficiently high purity to permit its use without lessening the accuracyof the determination.7.2 P
24、urity of WaterUnless otherwise indicated, references to water shall be understood to mean Types II or III reagent wateras defined in Specification D1193.7.3 Methanol, Carbonyl-freeTo 4 L of methanol add 20 g of 2,4-dinitrophenylhydrazine and 2 mL of hydrochloric acid (HCl,sp gr 1.19). Reflux for 2 h
25、 and then distill using a 2 to 3-ft fractionating column. Discard the first 200 mL of distillate. Continuethe distillation until approximately 75 % of the methanol has distilled over.7.3.1 WarningDo not allow the pot to begin to go dry because there is danger of a violent decomposition of the residu
26、e. (See8.2.) If stored in a tightly capped bottle, the methanol will remain carbonyl-free indefinitely. Properly prepared methanol will havean absorbance of 0.08 or less when used as a blank (11.2 11.4).7.4 Potassium Hydroxide Solution (100 g/L)Dissolve 100 g of potassium hydroxide (KOH) in 200 mL o
27、f water. Cool anddilute to 1 L with methanol.7.5 2,4-Dinitrophenylhydrazine (1 g/L)Dissolve 0.10 g of 2,4-dinitrophenylhydrazine (WarningSee 8.2) in 50 mL ofcarbonyl-free methanol containing 4 mL of hydrochloric acid (HCl, sp gr 1.19) and dilute to 100 mL with water. This solution isunstable and mus
28、t be discarded after two weeks.4 Lappin, G. R., and Clark, L. C., Analytical Chemistry, Vol 23, 1951, p. 541.5 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe American Chemical Society
29、, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.E411 17a28. Safety Hazards8.1 WarningThe toxicity of 2,4-dinitrophenylhydrazine has not been established
30、. For this reason, handle with customarycare. Avoid ingestion and contact of the compound with the skin and eyes.8.2 Warning2,4-Dinitrophenylhydrazine is an explosive and may ignite violently in contact with an open flame or electricalspark. Handle with caution. Avoid all sources of heat.9. Sampling
31、9.1 Special precautions may be necessary to ensure that the sample taken for analysis is representative of the whole. Refer toPractice E300 for a detailed discussion of sampling procedures.10. Calibration10.1 Add 50 mL of carbonyl-free methanol to a 100-mL glass stoppered volumetric flask. To the fl
32、ask transfer an amount ofthe carbonyl compound being determined that will contain 25 mg of CO, weighing to the nearest 0.1 mg (see Note 4). Dilute thecontents of the flask to the mark with carbonyl-free methanol and mix well (see Note 5). (See 5.5 and 6.3.)NOTE 4The correct weight may be calculated
33、as follows:W 50.8933E (1)where:W = weight, mg,E = equivalent weight of compound, and0.893 = derived as a solution to the equation: W 28/E = 25, where 28 is the molecular weight of CO, and 25 is milligramsof CO to be determined. Solve this equation for W. Thus: W = 25 E/28, which simplifies to W = (2
34、5/28) E. 25/28= 0.893.NOTE 5For most routine work a calibration based on 2-butanone is satisfactory. (See 5.4.)10.2 Prepare a series of standards by transferring 2, 4, 6, 8, and 10-mL aliquots of this stock solution to respective 100-mLglass-stoppered volumetric flasks. Dilute the contents of each f
35、lask to the mark with carbonyl-free methanol and mix well. Twomillilitres of each of these standards contain approximately 10, 20, 30, 40, and 50 g of carbonyl, respectively. Calculate the exactweight as follows:S 55.603W 3V!/E# (2)where:S = weight of carbonyl in 2 mL of solution, g,W = weight of sa
36、mple added to stock solution, mg,E = equivalent weight of compound,V = volume of aliquot, mL, and5.60 = collection of constants: S = (W mg 1 g/1000 mg)/100 mL (V mL/100 mL) (1 eq 2-butanone/E) (1 eq C = O/1 eq2-butanone) (28 g/eq C = O) (1000000 ug/g) 2 = 5.6 (W V)/E.10.3 Using suitable pipets, tran
37、sfer 2 mL of each standard to respective 25-mL glass-stoppered volumetric flasks. Develop thecolor and measure the absorbance of each standard as described in 11.2 11.4.10.4 Plot, on linear graph paper, micrograms of carbonyl as a function of the net absorbance.NOTE 6If the photometer reading is tra
38、nsmittance, convert to absorbance as follows:A 5log10 100/T (3)where:A = absorbance, andT = transmittance.11. Procedure11.1 Using a suitable pipet, transfer 2 mL of a sample containing 0.5 to 50 g of carbonyl to a 25-mL dry glass-stopperedvolumetric flask that has previously been tared to the neares
39、t 0.1 mg. Restopper and again weigh to the nearest 0.1 mg to obtainthe exact sample weight. (See 5.5 and 6.3.)NOTE 7If 2 mL of the sample contains more than 50 g of carbonyl, a suitable dilution in water or carbonyl-free methanol should be made.11.2 Transfer 2 mL of carbonyl-free methanol to a secon
40、d 25-mL glass-stoppered volumetric flask for use as a reagent blank.11.3 To each flask, transfer, by means of a pipet, 2 mL of the 2,4-dinitrophenylhydrazine solution. Stopper and allow to set atroom temperature for 30 6 2 min (see Note 8). Dilute to the mark with the potassium hydroxide solution. S
41、topper and mix well.E411 17a3NOTE 8If a determination of easily hydrolyzed imines and acetals is required, use a reaction temperature of 60C. A hot-water bath is a convenientsource of heat. Cool before adding the potassium hydroxide solution.11.4 At 12 6 1 min after adding the potassium hydroxide so
42、lution, measure the absorbance of each solution at approximately480 nm (see Note 9) in a 1-cm cell using a suitable photometer. Use a 1-cm cell filled with water to set the instrument at zeroabsorbance or 100 % transmittances.NOTE 9The maximum absorbance of the quinoidal ion occurs at about 430 nm.
43、The absorbance-concentration relationship is more linear, however,at 480 nm. For this reason the latter wavelength is used.11.5 Calculate the net absorbance due to carbonyl compounds in the sample by subtracting the absorbance of the reagent blankfrom that of the sample determinations.11.6 Refer to
44、a previously prepared calibration curve to determine the micrograms of carbonyl found.12. Calculations12.1 Calculate the carbonyl content of the sample as follows:CO,g/g5AB (4)where:A = weight of carbonyl found, g, andB = sample weight, g, or sample volume, mL sp gr.12.2 If it is desired to express
45、the carbonyl content as a specific compound, multiply the content calculated above by the factorE/28.01, where E is the equivalent weight of the compound.13. Report13.1 Report the carbonyl content to the nearest 0.1 g/g. Duplicate runs that agree within 0.5 g/g absolute are acceptable foraveraging (
46、95 % probability).14. Precision and Bias14.1 PrecisionThe following criteria should be used for judging the acceptability of results (see Note 10).14.1.1 Repeatability (Single Analyst)The standard deviation for a single determination has been estimated to be 0.16 g/g at26 df. The 95 % limit for the
47、difference between two such determinations is 0.4 g/g absolute.14.1.2 Laboratory Precision (Within-Laboratory, Between-Days Variability)The standard deviation of results (each theaverage of duplicates) obtained by the same analyst in different days, has been estimated to be 0.16 g/g absolute at 13 d
48、f. The95 % limit for the difference between two such averages is 0.4 g/g absolute.14.1.3 Reproducibility (Multilaboratory)The coefficient of variation of results (each the average of duplicates), obtained byanalysts in different laboratories has been estimated to be 6.04 % relative at 5 df. The 95 %
49、 limit for the difference between twosuch averages is 17 % relative.NOTE 10The precision estimates are based on an interlaboratory study performed in 1969 on two samples of methanol containing 4 and 24 g/g totalcarbonyl added as acetone. Seven laboratories analyzed the samples in duplicate on each of two days.6 Practice E180 90 was used in developing theseprecision statements.14.2 BiasThe bias of this test method has not been determined due to the unavailability of suitable reference materials.15. Quali
