1、Designation: D2192 06 (Reapproved 2012)Standard Test Method forPurity of Aldehydes and Ketones1This standard is issued under the fixed designation D2192; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、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 the purityof certain commercially available aldehydes and ketones.1.2 In addition to all
3、aldehydes and ketones, all compoundssuch as vinyl alkyl ethers, acetals, and ketals, that hydrolyzeunder the conditions of the reaction to form free carbonylgroups, react with the reagent and consequently interfere.Water, alcohols, saturated esters, and hydrocarbons do not reactwith the reagent, but
4、 large amounts of inert organic solvents areundesirable because of the effect on the indicator.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 “to the nearestunit” in the last righ
5、t-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 This standard does not purport to address all of thesafety
6、 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 regulatory limitations prior to use. For specific hazardstatements, see Section 7.1.6 For hazard information and
7、guidance, see the suppliersMaterial Safety Data Sheet.2. Referenced Documents2.1 ASTM Standards:2D268 Guide for Sampling and Testing Volatile Solvents andChemical Intermediates for Use in Paint and RelatedCoatings and MaterialD1193 Specification for Reagent WaterE29 Practice for Using Significant Di
8、gits in Test Data toDetermine Conformance with SpecificationsE200 Practice for Preparation, Standardization, and Storageof Standard and Reagent Solutions for Chemical AnalysisE222 Test Methods for Hydroxyl Groups Using AceticAnhydride Acetylation3. Summary of Test Method3.1 Hydroxylamine hydrochlori
9、de is converted in part tofree hydroxylamine by reaction with a known amount ofaqueous triethanolamine.NH2OHHCl1HOCH2CH2!3N (1)NH2OH1HOCH2CH2!3NHClThe free hydroxylamine reacts with the aldehyde or ketoneto form the corresponding oxime.RR1C 5 01NH2OHRR1C 5 H 5 NOH1H2O, (2)where:R = alkyl group andR1
10、= alkyl group or hydrogen.The amount of hydroxylamine consumed, which is deter-mined by titration of the excess base with standard sulfuricacid, is a measure of the aldehyde or ketone originally present.3.2 Since the determination is based on an acidimetrictitration, a suitable correction must be ap
11、plied if the sample isnot neutral to bromophenol blue indicator.4. Significance and Use4.1 This test method provides a measurement of purity(assay) of aldehydes and ketones. The results of these mea-surements can be used for specification acceptance.4.2 The precision of this test method is applicabl
12、e only tomaterial having a purity of 98 to 100 %.5. Apparatus5.1 Pressure Bottle, 200 to 350-mL capacity, with lever typeclosure and made of heat-resistant glass.5.2 Container for Pressure BottleA suitable safety deviceto contain the pressure bottle. A metal container with a hinged1This test method
13、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, Plasticizers, and Chemical Intermediates.Current edition approved June 1, 2012. Published July 2012. Originally approvedin 196
14、3. Last previous edition approved in 2006 as D2192 06 . DOI: 10.1520/D2192-06R12.2For 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
15、 onthe ASTM website.*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 States1top and perforated bottom, a strong synthetic fabric or canvasbag, or a safety shield may be used.5.3
16、 Ampoule, 1 or 2-mL capacity.5.4 Weighing Pipet, Lunge or similar type.5.5 Burets, 50-mL capacity.5.6 Transfer Pipet, 50-mL capacity.5.7 Glass Rod, 8-mm, several pieces approximately 1 in.long.5.8 Boiling Water Bath.6. Reagents and Materials6.1 Purity of ReagentsReagent grade chemicals shall beused
17、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 reagent
18、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 conformingto Type IV of Specification D1193.6.3 Bromophenol Blue Indicator (0.04 % AlcoholicS
19、olution)Dissolve 0.04 g of bromophenol blue (tetrabro-mophenolsulfonphthalein) in 100 mL of methyl alcohol. Titratethis solution with 0.1 N sodium hydroxide (NaOH) solution toa reddish-bronze color. If an off-color is obtained at this point,it is probably due to the age of the indicator and fresh in
20、dicatorshould be used to prepare a new solution.6.4 Cylinder Nitrogen.6.5 Hydroxylamine Hydrochloride, Standard (0.5 N Alco-holic Solution)Dissolve 35 g of hydroxylamine hydrochlo-ride (NH2OH HCl) in 150 mL of water and dilute to 1 L with99 % isopropanol.6.6 Isopropanol (99 %).6.7 Sulfuric Acid, Sta
21、ndard (0.5 N)Prepare and standard-ize 0.5 N sulfuric acid (H2SO4) in accordance with PracticeE200, sections on Precision and Bias, Standardization withTris(hydroxymethyl)-Aminomethane, Calculation, and Stabil-ity.6.8 Triethanolamine, Standard (0.5 N Aqueous Solution)Dissolve 65 mL (74 g) of 98 % tri
22、ethanolamine in water anddilute to 1 L with water. Adjust the normality of this solutionso that it is slightly below the normality of the H2SO4beingused.7. Procedure7.1 Sample the material in accordance with Guide D268.7.2 Add 15 mL of a 0.04 % alcoholic solution of bromophe-nol blue indicator to 50
23、0 mL of the hydroxylamine hydrochlo-ride solution. From a buret add 0.5 N triethanolamine until thesolution appears greenish-blue by transmitted light. Prepare thesolution fresh before each series of analyses.7.3 Prepare a sufficient number of heat-resistant pressurebottles to make all blank and sam
24、ple determinations in dupli-cate. Replace the rubber gaskets if necessary and make sure thecaps can be fastened securely.7.4 Using a graduated cylinder, add 65 mL of the neutral-ized hydroxylamine hydrochloride to each bottle. Using atransfer pipet, add 50.0 mL of the 0.5 N triethanolaminesolution t
25、o each bottle.7.5 Before capping, purge the bottles for 2 min with a gentlestream of cylinder nitrogen. This is best accomplished bymeans of a glass tube inserted through the neck of the bottleand clamped so that the opening is just above the surface of theliquid.7.6 Reserve two of the bottles for t
26、he blank determination.Into each of the other bottles introduce an amount of samplecontaining not more than 0.015 mol of aldehyde or ketone. Forsubstantially pure material, weigh the specimen to the nearest0.1 mg, using the amount and procedure specified in Table 1.7.6.1 Warning: Acetaldehyde is a h
27、ighly volatile, flam-mable material; observe all necessary safety precautions.Handle samples only in a fume hood that is free from openflames, electric heaters, and other sources of ignition. Cool allsamples in an ice bath before the containers are opened. Weighthe acetaldehyde in a sealed glass amp
28、oule. The actual proce-dure for filling and sealing the ampoule will vary somewhatwith the type of ampoule being used. One convenient methodis to pack commercially available ampoules in powdered, solidcarbon dioxide, introduce the specimen by means of a chilledhypodermic syringe, and seal the ampoul
29、e with a gas torch.7.7 If a sealed glass ampoule is used to weigh the specimen,add several pieces of 8-mm glass rod and shake the bottlevigorously to break the ampoule.7.8 React the solutions at room temperature or at 98Caccording to the directions in Table 1.7.8.1 Reaction at 98C (WarningSee 7.8.1.
30、1.)Placethe specimen and blank bottles as close together as possible ina boiling water bath maintained at least at 98C for the timespecified in Table 1. Maintain sufficient water in the bath to justcover the liquid in the bottles. Remove the bottles from thebath after the specified time and allow th
31、em to cool in air to3Reagent 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 Unit
32、ed States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.TABLE 1 Specimen Size and Reaction ConditionsCompoundSpecimen,gAMinimum ReactionConditionsTime,minTempera-ture, CAcetaldehyde ( 7.6.1) 0.5 to 0.7B30 25Methyl isobutyl ketone 1.1 to 1.4B60 25Methyl
33、isoamyl ketone 1.1 to 1.7 30 25Isophorone 1.4 to 2.0 60 98AUse a suitable weighing pipet unless otherwise specified.BUse a sealed glass ampoule.D2192 06 (2012)2room temperature. When the bottles have cooled, remove themfrom the safety device and continue as described in 7.9.7.8.1.1 Warning: Enclose
34、each bottle securely in a suitablecontainer (metal or strong fabric) to restrain fragments of glassshould the pressure bottle rupture.7.8.2 Reaction at Room TemperatureAllow the specimensand the blanks to stand together at room temperature for thelength of time specified in Table 1. Swirl the bottle
35、s occasion-ally.7.9 Cool each of the bottles slightly with tap water anduncap carefully to prevent loss of the contents. Allow thecontents to return to room temperature.NOTE 1Bromophenol blue indicator is temperature sensitive, and adifference of 10C at the end point causes a discrepancy of approxim
36、ately0.3 mL of 0.5 N H2SO4. To achieve the best precision, it is imperative thatthe blank and the specimen be at the same temperature at the end point. Awater bath at room temperature is a convenient means of conditioning thespecimen and the blanks prior to the titration.7.10 Titrate each of the bla
37、nks with standard 0.5 N H2SO4toa greenish-blue end point. Titrate each of the specimens withstandard 0.5 N H2SO4to the color of the blanks, approachingthe end point dropwise until the colors match by transmittedlight.NOTE 2If the solution becomes cloudy upon titration, add sufficientisopropanol to t
38、he specimen solution to effect homogeneity and add anequal amount of isopropanol also to the blank.7.11 Measure the temperature of the acid titrant. If thetemperature of the reagent at the time the analysis is made isnot the same as it was when the reagent was standardized,apply a correction to the
39、normality. Use a DN/ T of 0.00014 perdegree Celsius in making the temperature correction.48. Calculation8.1 Calculate the weight percent of aldehyde or ketone, A,as follows (Note 3):A 5 B 2 V!F 3 N!/S# 3100 (3)where:V =H2SO4required for titration of the specimen (see 7.10),mLB =H2SO4required for tit
40、ration of the blanks (see 7.10),average, mLN = normality of the H2SO4,F = factor specified in Table 2 for the compound beingdetermined, andS = sample used (see 7.6), g.NOTE 3If the sample is acidic to bromophenol blue indicator, it isrecommended that a suitable correction be applied to the purity va
41、lue.Refer to Test Method E222.9. Report9.1 Report all results to the nearest 0.1 %.10. Precision and Bias10.1 PrecisionIn interlaboratory studies of this testmethod, the within-laboratory and between-laboratory standarddeviations were found to be as shown in Table 3 and Table 4.Based on these deviat
42、ions, the following criteria should beused for judging the acceptability at the 95 % confidence levelof results obtained on materials having a purity of 98 to 100 %.10.2 RepeatabilityTwo results, each the mean of dupli-cates, obtained by the same operator on different days, shouldbe considered suspe
43、ct if they differ by more than the amountshown in Table 3.10.3 ReproducibilityTwo results, each the mean of dupli-cates, obtained by operators in different laboratories, should beconsidered suspect if they differ by more than the amountshown in Table 4.NOTE 4The preceding precision statements for ac
44、etaldehyde arebased upon two separate interlaboratory studies using two differentsamples having purities above 99 %. In the first study duplicate determi-nations were made on each sample by two analysts on two different daysin each of three laboratories. The second study included the same testprogra
45、m in each of four laboratories.The precision statements for methyl isoamyl ketone and isophorone arebased upon two separate interlaboratory studies using two differentsamples of each chemical. In both studies, one analyst in each of elevendifferent laboratories made duplicate determinations on each
46、sample ontwo different days.10.4 BiasThe bias of this test method has not beendetermined because suitable standards are unavailable.11. Keywords11.1 aldehyde; ketones; purity4See table titled Temperature Correction Factors (F) of Practice E200.TABLE 2 Aldehyde and Ketone FactorsCompound FactorAAceta
47、ldehyde 0.04405Methyl isobutyl ketone 0.1002Methyl isoamyl ketone 0.1142Isophorone 0.1382AFactor5Molecular weight of compoundNumber of reacting groups31000TABLE 3 Within-Laboratory DeviationsAcetalde-hydeMethylIsoamylKetoneIsophoroneStandard deviation 0.33 0.22 0.18Degrees of freedom 20 42 42Repeata
48、bility 1.0 2.6 0.6TABLE 4 Between-Laboratory DeviationsAcetalde-hydeMethylIsoamylKetoneIsophoroneStandard deviation 0.33 0.41 0.63Degrees of freedom 20 19 19Reproducibility 1.0 1.2 1.9D2192 06 (2012)3SUMMARY OF CHANGESCommittee D01.35 has identified the location of selected changes to this standard
49、since the last issue(D2192 - 96 (2000) that may impact the use of this standard. (Approved June 1, 2006.)(1) Added reference to Practice E29 in 1.3 of the Scopesection.(2) Added Practice E29 to list of Referenced Documents.ASTM 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 advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsi
