1、Designation: D612 88 (Reapproved 2017)Standard Test Method forCarbonizable Substances in Paraffin Wax1This standard is issued under the fixed designation D612; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. 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 U.S. Department of Defense.1. Scope1.1 This test method covers determination of ca
3、rbonizablesubstances in paraffin wax. The test method is applicable toparaffin wax for pharmaceutical use, as defined by the U.S.National Formulary, with a melting point as determined inaccordance with Test Method D87, between 117 F and 149 F(47 C and 65 C).1.2 The values stated in inch-pound units
4、are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibili
5、ty 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. Specific warningstatements are given in Annex A1.1.4 This international standard was developed in accor-dance with internationally recognized
6、 principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D87 Test Method for Meltin
7、g Point of Petroleum Wax(Cooling Curve)D1193 Specification for Reagent Water3. Summary of Test Method3.1 Five millilitres of melted wax are treated with 5 mL ofconcentrated, nitrogen-free sulfuric acid at 158 F (70 C). Thecolor of the acid layer is compared with that of a colorimetricreference stand
8、ard. If the color is not darker than the standard,the wax is reported as passing the test.4. Significance and Use4.1 This test method is a means for ascertaining whetherpharmaceutical paraffin wax conforms to the standards forquality prescribed by the U.S. National Formulary.5. Apparatus5.1 Test Tub
9、e, as shown in Fig. 1, of heat-resistant glass (seeNote 1) fitted with a well-ground glass stopper, the stopper andthe tube bearing identical and indestructible numbers. The tubeshall be 140 mm 6 2 mm in length and between 14.5 mm and15.0 mm in outside diameter, and shall be calibrated at the5mL 6 0
10、.2 mL and 10 mL 6 0.2 mL liquid levels. Thecapacity of the tube with stopper inserted shall be between13.6 mL and 15.6 mL. A rolled edge may be provided forsuspending the tube on the cover of the water bath.NOTE 1Borosilicate glass has been found satisfactory for this pur-pose.5.2 Water Bath, suitab
11、le for immersing the test tube abovethe 10 mL line and equipped to maintain a temperature of158 F 6 1.0 F (70 C 6 0.5 C). The bath shall be providedwith a cover of any suitable material, with holes approximately16 mm in diameter through which the test tubes may besuspended.5.3 Color Comparator, of a
12、 suitable type for observing thecolor of the acid layer in comparison with the referencestandard color solution. The size and shape of the comparatorare optional, but the size and shape of the apertures shallconform to the dimensions prescribed in Fig. 1.6. Reagents6.1 Purity of ReagentsReagent grad
13、e chemicals shall beused in all tests. Unless otherwise indicated, it is intended that1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.10.0A on Physical/Chemical Properties.Current
14、 edition approved June 1, 2017. Published July 2017. Originally approvedin 1941. Last previous edition approved in 2012 as D612 88 (2012). DOI:10.1520/D0612-88R17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book
15、 of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recogniz
16、ed principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1all reagents shall conform to the specifications of the Commit-tee
17、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 is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.6.2 Purity of WaterUnless oth
18、erwise indicated, referencesto water shall be understood to mean distilled water, such asreagent water corresponding to Specification D1193, Type III,or water of equal purity.6.3 Cobaltous Chloride Solution (0.5 N)Dissolve about65 g of cobaltous chloride (CoCl26H2O) in enough dilutedhydrochloric aci
19、d (HCl, 1 + 39) (WarningHydrochloric acid(concentrated) causes burns, vapor extremely irritating. SeeA1.2) to make 1000 mL of solution. Transfer exactly 5 mL ofthis solution to a flask; add 15 mL of sodium hydroxide(NaOH, 1 + 5) (WarningSodium hydroxide, corrosive, cancause severe burns or blindness
20、. Evolution of heat produces aviolent reaction or eruption upon too rapid a mixture withwater. See A1.4), and 5 mL of hydrogen peroxide. Boil for10 min, cool, and add 2 g of potassium iodide (KI) and 20 mLof sulfuric acid (H2SO4, 1+4) (WarningSulfuric acid(concentrated) causes burns, vapor irritatin
21、g, strong oxidizer.See A1.3). When the precipitate has dissolved, titrate theliberated iodine with 0.1 N sodium thiosulfate (Na2S2O3)solution using starch solution as an indicator. Each millilitre of0.1 N Na2S2O3solution consumed is equivalent to 0.023799 gof CoCl26H2O. Adjust the final volume of Co
22、Cl2solution bythe addition of diluted HCl (1 + 39) so that 1 mL contains59.5 mg of CoCl26H2O.6.4 Colorimetric Reference Standard SolutionPrepare areference standard pale amber solution for color comparison bymixing together 1.5 parts of CoCl2solution, 3.0 parts of FeCl3solution, and 0.5 parts of CuS
23、O4solution. Measure 5 mL ofthis mixture into a test tube as specified in 3.1. This pale amberreference standard shall then be overlaid with 5 mL of whitemineral oil.6.5 Cupric Sulfate Solution (0.5 N)Dissolve about 65 g ofcupric sulfate (CuSO45H2O) in enough diluted HCl (1 + 39)(WarningHydrochloric
24、acid (concentrated) causes burns,vapor extremely irritating. See A1.2) to make 1000 mL ofsolution. Transfer exactly 10 mL of this solution to a flask, add50 mL of water, 4 mL of acetic acid (WarningAcetic acid(glacial) is corrosive, combustible, vapor irritating. See A1.5),and 3 g of KI.Allow the mi
25、xture to stand for 5 min, then titratethe liberated iodine with 0.1 N Na2S2O3solution, using starchsolution as an indicator. Each millilitre of 0.1 N Na2S2O3solution is equivalent to 0.02497 g of CuSO45H2O. Adjust thefinal volume of CuSO4solution by the addition of diluted HCl(1 + 39) so that 1 mL c
26、ontains 62.4 mg of CuSO45H2O.6.6 Ferric Chloride Solution (0.5N)Dissolve about 55 gof ferric chloride (FeCl36H2O) in enough diluted HCl(WarningHydrochloric acid (concentrated) causes burns,vapor extremely irritating. See A1.2) (1 + 39) to make1000 mL of solution. Transfer exactly 10 mL of the soluti
27、on toa flask, add 5 mL of HCl (sp gr 1.19), 25 mL of water, andabout 3 g of KI. Stopper and allow the mixture to stand for5 min. Dilute the mixture with 50 mL of water, and titrate theliberated iodine with 0.1 N Na2S2O3solution, using starchsolution as an indicator. Each millilitre of 0.1 N Na2S2O3s
28、olution is equivalent to 0.02703 g of FeCl36H2O. Adjust thefinal volume of the FeCl3solution by the addition of dilutedHCl (1 + 39) so that 1 mL contains 45.0 mg of FeCl36H2O.6.7 Sulfuric Acid (94.7 6 0.2 %)The sulfuric acid(H2SO4)(WarningSulfuric acid (concentrated) causesburns, vapor irritating, s
29、trong oxidizer. See A1.3) shall be3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K.
30、, and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.FIG. 1 Color Comparator for Carbonizable Substances in Liquid PetrolatumD612 88 (2017)2nitrogen-free when analyzed in accordance with the followingprocedure: Dilute a small amount of
31、the acid with an equalvolume of water and superimpose 10 mL of the cooled liquidupon diphenylamine solution (1 g of diphenylamine in 100 mLof concentrated H2SO4). A blue color should not appear at thezone of contact within 1 h. This test detects as little as0.0002 % NO3.7. Procedure7.1 Clean a test
32、tube with cleaning solution of sulfuric acidand Nochromix4(WarningNochromix4is corrosive. SeeA1.1), rinse with tap water followed by distilled water, and dryin an oven at 105 C for 1 h.7.2 Melt a representative portion of the sample on a steambath or hot water bath. Fill the test tube to the 5 mL ma
33、rk withH2SO4(94.7 % 6 0.2 %). Then add the melted wax, at atemperature not more than 10 F (5.5 C) above its meltingpoint, to the 10 mL mark, insert the stopper loosely, and placethe test tube in position in the water bath at 158 F 6 1.0 F(70 C 6 0.5 C).7.3 After the test tube has been in the water b
34、ath for 5 min,loosen the stopper sufficiently to release any pressure andreinsert, remove the test tube from the bath quickly, hold witha finger over the stopper, and give three vigorous, verticalshakes over an amplitude of about 5 in. (127 mm), shaking thetest tube quickly and at a rate correspondi
35、ng to 5 shakes/s.Repeat every minute. Do not keep the test tube out of the bathlonger than 3 s for each shaking period.NOTE 2A shaking machine may be used provided that the resultsobtained agree with those obtained by the prescribed manual agitation.7.4 At the end of 10 min from the time the test tu
36、be was firstplaced in the bath, remove the test tube, immediately place it inthe color comparator, and compare the acid layer with 5 mL ofthe standard colorimetric solution and 5 mL of white mineraloil in a test tube that has been shaken vigorously for 10 s andallowed to stand just long enough for t
37、he contents to separateinto two layers.7.5 In some cases the acid remains trapped with the wax asan emulsion, and no lower layer is obtained to compare withthe standard colorimetric solution. When this occurs, comparethe emulsion with the standard colorimetric solution and whitemineral oil shaken vi
38、gorously to give a similar emulsion, andwithout waiting for the two liquids to separate.8. Interpretation of Results8.1 Paraffin wax shall be reported as passing the test whenthe acid layer is not darker than the reference standardcolorimetric solution or, if completely emulsified, when theemulsion
39、is not darker than a similar emulsion produced byvigorously shaking the reference standard colorimetric solutionwith white mineral oil in equal proportions.8.2 If the acid layer is darker than the reference standardcolorimetric solution, or if the emulsified paraffin wax and acidare darker than a si
40、milar emulsion of the reference standardcolorimetric solution and white mineral oil in equalproportions, the paraffin wax shall be reported as not passingthe test.9. Precision and Bias9.1 No statement is made about either the precision or thebias of this test method for measuring carbonizable substa
41、ncesin white refined waxes since the result only states whether thereis conformance to the criteria for success specified in theprocedure.10. Keywords10.1 carbonizable substances; petroleum wax; waxANNEX(Mandatory Information)A1. WARNING STATEMENTSA1.1 Glass Cleaning Solution (Nochromix4)A1.1.1 Warn
42、ingCorrosive, potent, clear liquid. Solutionis a mixture of sulfuric acid (concentrated) and Nochromix,4awhite crystalline, inorganic oxidizer.Handle carefully with special highly acid resistant glovesonly.Do not close container airtight.A1.2 Hydrochloric Acid (Concentrated)A1.2.1 WarningPoison. Cor
43、rosive. May be fatal if swal-lowed. Liquid and vapor cause severe burns. Harmful ifinhaled.Do not get in eyes, on skin, or on clothing.Do not breathe vapor, spray, or mist.Dilute by addition of acid to water.Keep in tightly closed container in approved acid storagecabinet.Keep cool.Loosen closure ca
44、refully when opening.Use with adequate ventilation.Keep container closed when not in use.Use protective clothing and goggles when handling.Wash thoroughly after handling.4Nochromix is a trademark of Godax Laboratories, Inc., P.O. Box 422, CabinJohn, MD 20818.D612 88 (2017)3A1.3 Sulfuric Acid (Concen
45、trated)A1.3.1 Do not get in eyes, on skin or on clothing.Do not breathe vapor, spray, or mist.Dilute by addition of acid to water.Keep in tightly closed container in approved acid storagecabinet.Keep cool.Loosen closure carefully when opening.Use with adequate ventilation.Do not allow water to get i
46、nto container because of violentreaction.Keep container closed when not in use.Use protective clothing and goggles when handling.Wash thoroughly after handling.A1.4 Sodium HydroxideA1.4.1 Before using, secure information on procedures andprotective measures for safe handling.Do not get in eyes, on s
47、kin, or on clothing.Avoid breathing dusts or mists.Do not take internally.When handling, use chemical safety goggles or face shield,protective gloves, boots, and clothing.When mixing with water, add slowly to surface of solutionto avoid violent spattering. In the preparation of solutions donot use h
48、ot water, limit temperature rise, with agitation, to10C/min or limit solution temperature to a maximum of90 C. No single addition should cause a concentration in-crease greater than 5 %.A1.5 Acetic Acid (Glacial)A1.5.1 Do not get in eyes, on skin, or on clothing.Do not breathe vapor, spray or mist.D
49、ilute by addition of acid to water.Keep away from heat and open flame.Keep in tightly closed container in approved acid storagecabinet.Keep cool.Loosen closure carefully when opening.Use with adequate ventilation.Keep container closed when not in use.Use protective clothing and goggles when handling.Wash thoroughly after handling.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 determinatio
