ASTM E224-2008 781 Standard Test Methods for Analysis of Hydrochloric Acid《盐酸分析的标准试验方法》.pdf

1、Designation: E 224 08Standard 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 number in parenthes

2、es 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. Scope*1.1 These test methods cover the analysis of hydrochloricacid.1.2 The value

3、s stated in SI units are to be regarded asstandard. The values given in parentheses are for informationonly.1.3 The analytical procedures appear in the following order:SectionsTotal Acidity 8 to 16Baum Gravity 17 to 26Sulfated Ash 27 to 34Iron 35to44Color 45 to 52Total Sulfur 53 to 591.4 This standa

4、rd does not purport to address all of thesafety 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. Specific hazardsstatements ar

5、e given in Section 5 and 30.1, 39.7, and 48.4.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reagent WaterD 1209 Test Method for Color of Clear Liquids (Platinum-Cobalt Scale)E1 Specification for ASTM Liquid-in-Glass ThermometersE60 Practice for Analysis of Metals, Ores, and Rel

6、atedMaterials by Molecular Absorption SpectrometryE 100 Specification for ASTM HydrometersE 180 Practice for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial and Spe-cialty ChemicalsE 200 Practice for Preparation, Standardization, and Stor-age of Standard and Reagent S

7、olutions for ChemicalAnalysis3. Significance and Use3.1 These test methods provide for the classification ofvarious grades of hydrochloric acid and for the determinationof various impurities. Acid strength and impurity levels areimportant factors in many uses of hydrochloric acid.4. Purity of Reagen

8、ts4.1 Purity of ReagentsReagent grade chemicals shall beused 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 m

9、ay 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 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean Type II or Type IIIreagent water conforming to

10、 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 immediately by covering the spillwith vermiculite or some other inert absorbent material andsweeping into a pan. Dispose of the absorbent by

11、 flooding withwater and discarding in a suitable container. Flush the area withwater.6. Photometers and Photometric Practice6.1 Photometers and the photometric practice prescribed inthese test methods shall conform to Practice E60.1These test methods are under the jurisdiction of ASTM Committee E15

12、onIndustrial and Specialty Chemicals and are the direct responsibility of Subcommit-tee E15.02 on Product Standards.Current edition approved April 1, 2008. Published May 2008. Originallyapproved in 1965. Last previous edition approved in 2002 as E 224 96(2002).2For referenced ASTM standards, visit t

13、he 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 website.3Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washington,

14、 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 United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1*A Summary of C

15、hanges section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Sampling7.1 Sampling of hydrochloric acid is not within the scope ofthese test methods.7.2 The sample to be analyzed shall be consid

16、ered to be thatsample in a single bottle submitted to the analytical laboratory.7.3 The size of the sample shall be sufficient to perform allanalyses without the reuse of any portion of the sample.TOTAL ACIDITY8. Scope8.1 This test method covers the determination of the totalacidity of 27 to 37 % ma

17、ss (m/m) hydrochloric acid.9. Summary of Test Method9.1 Aweighed sample of acid is diluted in water and titratedwith standardized 0.5 meq/mL (N) sodium hydroxide solution,using phenolphthalein as the indicator.10. Interferences10.1 Acids other than hydrochloric and compounds thatconsume sodium hydro

18、xide 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.412.2 Sodium Hydroxide,

19、Standard Solution (0.5 meq/mL(N)See Practice E 200. Correct for differences in tempera-ture in accordance with the following formula:N 5 Ns1 0.00014 s 2 t! (1)where:N = normality meq/mL (N) of NaOH solution at tem-perature t,Ns= normality meq/mL (N) of NaOH solution at tem-perature s during standard

20、ization,s = temperature of NaOH solution during standardiza-tion, C, 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,

21、 depend-ing upon the 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 meq/mL (N) NaOH solution, and thentitrate

22、 the sample to a pink end point. Record the titration to thenearest 0.02 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 % mass (m/m) of hydro-chloric acid as follows

23、:Hydrochloric acid, % mass m/m!5SVN 3 0.03646WD3 100 (2)where:V = corrected mL of NaOH solution required for titra-tion of the sample,N = normality meq/mL (N) of the NaOH solution, andW = sample used, g.15. Report15.1 Report the % mass (m/m) of hydrochloric acid to thenearest 0.01 % mass (m/m).16. P

24、recision and Bias16.1 The following criteria should be used for judging theacceptability of results (see Note 1):16.1.1 Repeatability (Single Analyst)The coefficient ofvariation for a single determination has been estimated to be0.133 % mass (m/m) relative at 50 df. The 95 % limit for thedifference

25、between two such runs is 0.37 % mass (m/m)relative.16.1.2 Laboratory Precision (Within-Laboratory, Between-Days Variability)The coefficient of variation of results (eachthe average of duplicates), obtained by the same analyst ondifferent days, has been estimated to be 0.170 % mass (m/m)relative at 2

26、5 df. The 95 % limit for the difference between twosuch averages is 0.48 % mass (m/m) 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 % mass (m/m)

27、relative at 7 df. The 95 % limit forthe difference between two such averages is 0.80 % mass(m/m) relative.NOTE 1These precision estimates are based on an interlaboratorystudy of analyses performed in 1963 on three samples containingapproximately 28, 31, and 38 % mass (m/m) hydrochloric acid. Oneanal

28、yst in each of ten laboratories performed duplicate determinations and4This reagent is also described in Practice E 200.TABLE 1 Sample Size For Total AcidityHCl, % mass (m/m) Sample Size, g37 1.9 to 2.335 2.0 to 2.433 2.2 to 2.631 2.3 to 2.829 2.5 to 3.027 2.7 to 3.2E224082repeated one day later, fo

29、r a total of 120 determinations.5Practice E 180was used in developing 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

30、 of hydrochloric acid by means of a glasshydrometer 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 2 145/sp gr 15.5/1

31、5.5C 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 ofhydrochloric ac

32、id.21. Apparatus21.1 Hydrometer,6streamline or torpedo design, precisiongrade, for liquids heavier than water in ranges from 17.5 to23B. The total length shall be approximately 305 mm (12 in.)divided to 0.1B over a 152-mm (6-in.) (approximate) scaleand standardized at 15.5/15.5C (60/60F) with a tole

33、rance 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 accordanc

34、e with Specification E1.21.3 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 the sam

35、ple, 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 at which

36、 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 specific

37、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 theacceptability of results (see Note 2):26.1.1 Repeata

38、bility (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)The standard deviation

39、of results (each theaverage of duplicates), obtained by the same analyst ondifferent days, has been estimated to be 0.046 unit absolute at24 df. The 95 % limit for the difference between two suchaverages is 0.1 unit absolute.26.1.3 Reproducibility (Multilaboratory)The standard de-viation of results

40、(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 an interlaboratorystudy of analyses perfo

41、rmed 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.5Practice E 180 was used indeveloping these precision estimates.26.2 BiasT

42、he 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 limit of determination of sulfated ash is 0

43、.001 % mass(m/m).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.5Details of the interlaboratory study are available from ASTM Inte

44、rnationalHeadquarters. Request RR: E15-1046.6See Specification E 100.E22408329.2 Muffle Furnace, maintained at 800 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. (Warni

45、ngUse goggles when preparing thissolution.)31. 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 mg (Note 5

46、).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 remaining from

47、 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.31.3 Transfer

48、 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 in a hood.

49、 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 % mass (m/m) of sulfated ash as follows(Note 6):Sulfated ash, % mass m/m!5RDW3 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