1、Designation: E 224 96 (Reapproved 2002)Standard Test Methods forAnalysis of Hydrochloric Acid1This standard is issued under the fixed designation E 224; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A n
2、umber in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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. Scope1.1 These test methods cover the analysis of hydrochlorica
3、cid.1.2 The analytical procedures appear in the following order:SectionsTotal Acidity 8 to 16Baum Gravity 17 to 26Sulfated Ash 27 to 34Iron 35 to 44Color 45 to 52Total Sulfur 53 to 591.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is there
4、sponsibility 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 hazardsstatements are given in Section 5 and 30.1, 39.7, and 48.4.2. Referenced Documents2.1 ASTM Standards:D 1193 Specifi
5、cation for Reagent Water2D 1209 Test Method for Color of Clear Liquids (Platinum-Cobalt Scale)3E 1 Specification for ASTM Thermometers4E 60 Practice for Analysis of Metals, Ores, and RelatedMaterials by Molecular Absorption Spectrometry5E 180 Practice for Determining the Precision of ASTMMethods for
6、 Analysis and Testing of Industrial Chemicals6E 200 Practice for Preparation, Standardization, and Stor-age of Standard and Reagent Solutions for ChemicalAnalysis63. Significance and Use3.1 These test methods provide for the classification ofvarious grades of hydrochloric acid and for the determinat
7、ionof various impurities. Acid strength and impurity levels areimportant factors in many uses of hydrochloric acid.4. Purity of Reagents4.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specificat
8、ions of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.7Other 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.4.2 Pu
9、rity of WaterUnless otherwise indicated, referencesto water shall be understood to mean Type II or Type IIIreagent water conforming to Specification D 1193.5. Hazards5.1 Hydrochloric acid is a corrosive acid and is dangerous ifimproperly handled. Avoid any skin contact.5.2 Clean up all spills immedi
10、ately by covering the spillwith vermiculite or some other inert absorbent material andsweeping into a pan. Dispose of the absorbent by flooding withwater and discarding in a suitable container. Flush the area withwater.6. Photometers and Photometric Practice6.1 Photometers and the photometric practi
11、ce prescribed inthese test methods shall conform to Practice E 60.7. Sampling7.1 Sampling of hydrochloric acid is not within the scope ofthese test methods.7.2 The sample to be analyzed shall be considered to be thatsample in a single bottle submitted to the analytical laboratory.7.3 The size of the
12、 sample shall be sufficient to perform allanalyses without the reuse of any portion of the sample.1These test methods are under the jurisdiction of ASTM Committee E15 onIndustrial and Specialty Chemicals and are the direct responsibility of Subcommit-tee E15.02 on Product Standards.Current edition a
13、pproved Oct. 10, 2002. Published February 2003. Originallyapproved in 1965. Last previous edition approved in 1996 as E 224 96.2Annual Book of ASTM Standards, Vol 11.01.3Annual Book of ASTM Standards, Vol 06.04.4Annual Book of ASTM Standards, Vol 14.03.5Annual Book of ASTM Standards, Vol 03.05.6Annu
14、al Book of ASTM Standards, Vol 15.05.7Reagent 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
15、.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.TOTAL ACIDITY8. Scope8.1 This test method covers the determinatio
16、n of the totalacidity of 27 to 37 % hydrochloric acid.9. Summary of Test Method9.1 A weighed sample of acid is diluted in water and titratedwith standardized 0.5 N sodium hydroxide solution, usingphenolphthalein as the indicator.10. Interferences10.1 Acids other than hydrochloric and compounds thatc
17、onsume sodium hydroxide will affect the accuracy of this testmethod.11. Apparatus11.1 Buret, 50-mL, Class A.11.2 Weighing Bottle, glass-stoppered, 50-mL.12. Reagents12.1 Phenolphthalein Indicator, Solution (10 g/L)Dissolve1gofphenolphthalein in 100 mL of ethanol (95 %),methanol, or isopropanol.812.2
18、 Sodium Hydroxide, Standard Solution (0.5 N)SeePractice E 200. Correct for differences in temperature inaccordance with the following formula:N 5 Ns1 0.00014 s 2 t! (1)where:N = normality of NaOH solution at temperature t,Ns= normality of NaOH solution at temperature s duringstandardization,s = temp
19、erature of NaOH solution during standardiza-tion, andt = temperature of NaOH solution during analysis, C.13. Procedure13.1 Transfer approximately 30 mL of water to a 50-mLglass-stoppered weighing bottle, stopper, and weigh to thenearest 0.1 mg. Rapidly add a convenient size sample, depend-ing upon t
20、he acid strength as given in Table 1, stopperimmediately, and reweigh. Transfer the sample to a 400-mLbeaker containing approximately 50 mL of water and add 3 to5 drops of phenolphthalein indicator solution. Record thetemperature of the 0.5 N NaOH solution, and then titrate thesample to a pink end p
21、oint. Record the titration to the nearest0.02 mL.14. Calculation14.1 Correct the buret reading for calibration errors, andrecord as V the corrected delivered volume at the recordedtemperature.14.2 Calculate the total acidity as percentage of hydrochlo-ric acid as follows:Hydrochloric acid, % 5SVN 3
22、0.03646WD3 100 (2)where:V = corrected mL of NaOH solution required for titra-tion of the sample,N = normality of the NaOH solution, andW = sample used, g.15. Report15.1 Report the percentage of hydrochloric acid to thenearest 0.01 %.16. Precision and Bias16.1 The following criteria should be used fo
23、r judging theacceptibility of results (see Note 1):16.1.1 Repeatability (Single Analyst)The coefficient ofvariation for a single determination has been estimated to be0.133 % relative at 50 df. The 95 % limit for the differencebetween two such runs is 0.37 % relative.16.1.2 Laboratory Precision (Wit
24、hin-Laboratory, Between-Days Variability), Formerly Called RepeatabilityThe coef-ficient of variation of results (each the average of duplicates),obtained by the same analyst on different days, has beenestimated to be 0.170 % relative at 25 df. The 95 % limit forthe difference between two such avera
25、ges is 0.48 % relative.16.1.3 Reproducibility (Multilaboratory)The coefficientof variation of results (each the average of duplicates), ob-tained by analysts in different laboratories, has been estimatedto be 0.285 % relative at 7 df. The 95 % limit for the differencebetween two such averages is 0.8
26、0 % relative.NOTE 1These precision estimates are based on an interlaboratorystudy of analyses performed in 1963 on three samples containingapproximately 28, 31, and 38 % hydrochloric acid. One analyst in each often laboratories performed duplicate determinations and repeated one daylater, for a tota
27、l of 120 determinations.9Practice E 180 was used indeveloping these precision estimates.16.2 BiasThe bias of this test method has not beendetermined due to the unavailability of suitable referencematerials.BAUM GRAVITY17. Scope17.1 This test method covers the determination of theBaum gravity of hydr
28、ochloric acid by means of a glass8This reagent is also described in Practice E 200.9Details of the interlaboratory study are available from ASTM InternationalHeadquarters. Request RR: E15 - 1046.TABLE 1 Sample Size For Total AcidityHCl, % Sample Size, g37 1.9 to 2.335 2.0 to 2.433 2.2 to 2.631 2.3 t
29、o 2.829 2.5 to 3.027 2.7 to 3.2E 224 96 (2002)2hydrometer in the range from 17.5 to 23 Baum. The Baumgravity is determined at 15.5C (60F).18. Terminology18.1 Definition:18.1.1 Baum gravitya unit of density based on specificgravity and defined by the following equation:Baum gravity 5 145 2145/sp gr 1
30、5.5/15.5C 60/60F!# (3)19. Summary of Test Method19.1 A sample of hydrochloric acid is placed in a hydrom-eter cylinder and when the temperature is constant, the Baumgravity is read from the glass hydrometer.20. Significance and Use20.1 The Baum gravity is used to classify various grades ofhydrochlor
31、ic acid.21. Apparatus21.1 Hydrometer,10streamline or torpedo design, precisiongrade, for liquids heavier than water in ranges from 17.5 to23B. The total length shall be approximately 12 in. (305 mm)divided to 0.1B over a 6-in. (152-mm) (approximate) scaleand standardized at 15.5/15.5C (60/60F) with
32、a tolerance of0.1B throughout. The modulus is as follows:B 5 145 2 145/sp gr 15.5/15.5C60/60F!# (4)Each of the hydrometers shall show on the scale the modulus(or formula).21.2 Thermometer, having a range from 2 to + 80C (30to 180F) and conforming to the requirements for Thermom-eter 15C (15F) in acc
33、ordance with Specification E 1.21.3 Cylinder, Hydrometer, glass with or without lip, diam-eter 38 to 40 mm, height 325 to 375 mm.22. Temperature of Test22.1 Baum gravity shall be determined at 15.56 0.3C (606 0.5F).23. Procedure23.1 Rinse a clean hydrometer cylinder with the sample tobe tested, add
34、the sample, and adjust the temperature to 15.5 60.3C (60 6 0.5F). Place the cylinder in a vertical position ina location free of air currents. Insert the hydrometer when it hascome to rest, floating freely, and the temperature is 15.5C(60F). The correct reading is that point of the hydrometerscale a
35、t which the surface of the liquid cuts the scale.Determine this point by placing the eye slightly below the levelof the liquid and slowly raising it until the surface, first seen asa distorted ellipse, appears to become a straight line cutting thehydrometer scale.24. Calculation24.1 Calculate the sp
36、ecific gravity for use in the determina-tion of iron using the following equation:sp gr 5145145 2 Be gravity!(5)25. Report25.1 Report the Baum gravity to the nearest 0.1 unit.26. Precision and Bias26.1 The following criteria should be used for judging theacceptibility of results (see Note 2):26.1.1
37、Repeatability (Single Analyst)The standard devia-tion for a single determination has been estimated to be 0.048unit absolute at 48 df. The 95 % limit for the differencebetween two such runs is 0.1 unit absolute.26.1.2 Laboratory Precision (Within-Laboratory, Between-Days Variability), Formerly Calle
38、d RepeatabilityThe stan-dard deviation of results (each the average of duplicates),obtained by the same analyst on different days, has beenestimated to be 0.046 unit absolute at 24 df. The 95 % limit forthe difference between two such averages is 0.1 unit absolute.26.1.3 Reproducibility (Multilabora
39、tory)The standard de-viation of results (each the average of duplicates), obtained byanalysts in different laboratories, has been estimated to be0.084 unit absolute at 7 df. The 95 % limit for the differencebetween two such averages is 0.2 unit absolute.NOTE 2These precision estimates are based on a
40、n interlaboratorystudy of analyses performed in 1963 on three samples having Baumgravities of approximately 18, 20, and 23 units. One analyst in each ofnine laboratories performed duplicate determinations and repeated oneday later, for a total of 108 determinations.9Practice E 180 was used indevelop
41、ing these precision estimates.26.2 BiasThe bias of this test method has not beendetermined due to the unavailability of suitable referencematerials.SULFATED ASH27. Scope27.1 This test method covers the gravimetric determinationof material not volatile after treatment with sulfuric acid. Thelower lim
42、it of determination of sulfated ash is 0.001 %.28. Summary of Test Method28.1 A weighed sample of acid, to which sulfuric acid hasbeen added, is evaporated, ignited, and the residue weighed.29. Apparatus29.1 Evaporating Dish, platinum or high-silica glass, 150-mL.29.2 Muffle Furnace, maintained at 8
43、00 6 25C (1472 645F).29.3 Crucible Tongs.30. Reagent30.1 Sulfuric Acid (1 + 1)Add slowly with stirring 1volume of concentrated sulfuric acid (H2SO4, sp gr 1.84) to 1volume of water. (WarningUse goggles when preparing thissolution.)10Suitable hydrometers are available from Walter H. Kessler, Inc., 16
44、0 Hicks St.,Westbury, L.I., NY 11590.E 224 96 (2002)331. Procedure31.1 Clean a platinum or a high-silica glass dish (seewarning above and Note 3) and ignite in a muffle furnace at800 6 25C (1472 6 45F) for at least 10 min. Cool in adesiccator to room temperature and weigh the dish to thenearest 0.1
45、mg (Note 5).NOTE 3New platinum or high-silica glass dishes should be boiled inhydrochloric acid (HCl, 1 + 1) for 10 min, washed, and ignited in themuffle furnace for at least 1 h before their first use.NOTE 4High-silica glass dishes should be used only for low nonvola-tile material. The residue rema
46、ining from samples containing largeamounts of nonvolatile matter may fuse into the dish.NOTE 5High-silica glass dishes should be allowed to cool at least 45min and platinum dishes at least 20 min before weighing.31.2 Mix the sample by inverting the sample bottle until allsolids are in suspension.31.
47、3 Transfer a weighed sample containing a minimum of50 g, weighed to the nearest 0.1 g, or a weighed sample ofsufficient size to yield not less than 1 mg of residue, to theevaporating dish, add 4 drops of H2SO4, evaporate almost todryness on a steam bath, and then to dryness over a burner orhotplate
48、in a hood. After evaporation, ignite the sample in themuffle furnace for 10 min. Use crucible tongs in handling theevaporating dish at all times.31.4 Allow the dish to cool to room temperature in adesiccator and rapidly weigh the sample dish to the nearest 0.1mg.32. Calculation32.1 Calculate the per
49、centage of sulfated ash as follows(Note 6):Sulfated ash, % 5R 2 D#W3 100 (6)where:R = weight of evaporating dish and residue, g,D = weight of evaporating dish, g, andW = sample used, g.NOTE 6When this value is less than 0.0010 %, report as less than0.0010 %.33. Report33.1 Report the percentage of sulfated ash to the nearest0.0001 %.34. Precision and Bias34.1 The following criteria should be used for judging theacceptibility of results (see Note 7):34.1.1 Repeatability (Single Analyst)The standard devia-tion for
