1、Designation: E223 08E223 16Standard Test Methods forAnalysis of Sulfuric Acid1This standard is issued under the fixed designation E223; 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 parenthe
2、ses 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. Scope*1.1 These test methods cover the analysis of sulfuric acid.1.2 The val
3、ues stated in SI units are to be regarded as standard. The values given in parentheses are for information only.1.3 The analytical procedures appear in the following order:SectionsTotal Acidity 8 to 16Total Acidity 8 to 16Baum Gravity 17 to 26Baum Gravity 17 to 26Nonvolatile Matter 27 to 33Nonvolati
4、le Matter 27 to 33Iron 34 to 43Iron 34 to 43Sulfur Dioxide 44 to 51Sulfur Dioxide 44 to 51Arsenic 52 to 61Arsenic 52 to 611.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appro
5、priate safety and health practices and determine the applicability of regulatorylimitations prior to use. Specific hazards statements are given in Section 5.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterE1 Specification for ASTM Liquid-in-Glass ThermometersE60 Pract
6、ice for Analysis of Metals, Ores, and Related Materials by SpectrophotometryE100 Specification for ASTM HydrometersE180 Practice for Determining the Precision of ASTM Methods for Analysis and Testing of Industrial and Specialty Chemicals(Withdrawn 2009)3E200 Practice for Preparation, Standardization
7、, and Storage of Standard and Reagent Solutions for Chemical Analysis3. Significance and Use3.1 These test methods provide for the classification of various grades of sulfuric acid and for the determination of variousimpurities. Acid strength and impurity levels are important factors in many uses of
8、 sulfuric acid.4. Purity of Reagents4.1 Purity of ReagentsReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, where1 These test me
9、thods are under the jurisdiction of ASTM Committee E15 on Industrial and Specialty Chemicals and are the direct responsibility of Subcommittee E15.02on Product Standards.Current edition approved April 1, 2008April 1, 2016. Published May 2008May 2016. Originally approved in 1965. Last previous editio
10、n approved in 20022008 asE223 96 (2002)E223 08.1. DOI: 10.1520/E0223-08.10.1520/E0223-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summa
11、ry 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 standard an indication of what changes have been made to the previous version. Becauseit may not
12、 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 is to be considered the official document.*A Summary of Changes section appears at the end
13、 of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1such specifications are available.4 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently highpurity to permit its use without l
14、essening the accuracy of the determination.4.2 Purity of WaterUnless otherwise indicated, references to water shall be understood to mean Type II or Type III reagentwater conforming to Specification D1193.5. Hazards5.1 Sulfuric acid is a strong corrosive acid and is dangerous if improperly handled.
15、Avoid any skin or eye contact.5.2 Clean up all spills immediately by covering the spill with vermiculite or some other inert absorbent material and sweepinginto a pan. Dispose of the absorbent by flooding with water and discarding in a suitable container. Flush the area with water.6. Photometers and
16、 Photometric Practice6.1 Photometers and the photometric practice used in these test methods shall conform to Practice E60.7. Sampling7.1 Sampling of sulfuric acid is not within the scope of these test methods.7.2 The sample to be analyzed shall be considered to be that sample in a single bottle sub
17、mitted to the analytical laboratory.7.3 The size of the sample shall be sufficient to perform all analyses without the reuse of any portion of the sample.TOTAL TOTALACIDITY8. Scope8.1 This test method covers the determination of the total acidity of 75 to 99 % mass (m/m) sulfuric acid. Two test meth
18、ods aregiven for weighing the sample, namely, the Dely tube and the snake tube test methods.9. Summary of Test Method9.1 Aweighed sample of acid is diluted in water and titrated with standardized 0.5 meq/mL(N) sodium hydroxide solution, usingphenolphthalein as the indicator.10. Interferences10.1 Aci
19、ds other than sulfuric and compounds that consume sodium hydroxide will affect the accuracy of this test method.11. Apparatus11.1 Dely Tube (Fig. 1) or Snake Tube (Fig. 2). 511.2 Buret, 100-mL, Class A, bulb-type.12. Reagents12.1 Phenolphthalein Indicator Solution (10 g/L)Dissolve 1 g of phenolphtha
20、lein in 100 mL of ethanol (95 %), methanol, orisopropanol.612.2 Sodium Hydroxide, Standard Solution (0.5 meq/mL(N)See Practice E200.4 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe Am
21、erican Chemical Society, 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),(USP), Rockville, MD.5 The sole source of supply of the Suitable Dely and snake tubes known to t
22、he committee at this time is Corning Glass Works, Corning, NY. If you are aware of alternativesuppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technicalcommittee,1 which you may attend.6 Th
23、is reagent is also described in Practice E200.TABLE 1 Sample Size for Total AcidityH2SO4, % mass (m/m) Sample Size, g98 1.9 to 2.294 2.0 to 2.390 2.1 to 2.485 2.2 to 2.680 2.3 to 2.777 2.4 to 2.875 2.5 to 2.9E223 16213. Procedure13.1 Dely Tube Test MethodInvert the sample bottle several times. (Hold
24、 the stopper in tight.) Insert the long arm of a dry,weighed Dely tube and withdraw by suction a convenient size sample depending upon the acid strength as given in Table 1 (Note1). Invert the Dely tube and wipe the acid from the long arm with disposable tissue several layers thick. Discard the tiss
25、ueimmediately to avoid burning the fingers. Reweigh to the nearest 0.0001 g and record the weight of the sample. Incline the tubeso that the acid runs back nearly to the bend of the short arm. Attach the short arm to an elevated water reservoir by means of arubber tube closed near the lower end with
26、 a pinch clamp. Insert the long arm of the Dely tube into 400-mLglass beaker containingapproximately 100 mL of water. Open the pinch clamp and flush the sample into the beaker. Continue the flow of water until allacid is washed from the Dely Tube (Note 2 and Note 3). Wash the long end of the Dely tu
27、be, collecting the washings in the beaker.Add 3 to 5 drops of phenolphthalein indicator solution. Record the temperature of the 0.5 meq/mL(N) NaOH solution, and thentitrate the sample to a pink end point. Record the titration to the nearest 0.02 mL.NOTE 1The Dely tube can be marked at points equival
28、ent to weights given in Table 1.NOTE 2The presence of acid in the Dely tube may be detected by coloring the water in the reservoir with phenolphthalein indicator and the minimumamount of dilute NaOH solution that will produce a slight pink. The water flowing through the tube is dicolorized as long a
29、s acid is present, and theappearance of a pink color indicates the absence of acid.NOTE 3The acid and water are separated by a bubble of air.FIG. 1 Dely TubeFIG. 2 Snake TubeE223 16313.2 Snake Tube Test MethodInvert the sample bottle several times. (Hold the stopper in tight). Insert the capillary e
30、nd of adry, weighed snake tube and withdraw by suction a convenient size sample depending upon the acid strength as given in Table1. Invert the tube so that the double bend is in a horizontal position. Wipe the acid from the capillary with disposable tissue severallayers thick. Discard the tissue im
31、mediately to avoid burning the fingers. Reweigh to the nearest 0.0001 g and record the weightof the sample. Submerge the capillary of the tube in approximately 100 mL of water contained in the 400-mL beaker. Force theweighed sample from the tube by a stream of water from a wash bottle by placing the
32、 delivery tip in the exposed end of the snaketube (Note 4). Wash the tube with 50 to 70 mL of water. Remove the tube and wash the outside free of acid. Swirl the contentsof the beaker gently while washing. Accumulate all washings in the beaker and add 3 to 5 drops of phenolphthalein indicatorsolutio
33、n. Record the temperature of the 0.5 meq/mL(N) NaOH solution, and then titrate the sample to a pink end point. Recordthe titration to the nearest 0.02 mL.NOTE 4Do not introduce the water into the snake tube too rapidly, as this will cause spattering.14. Calculation14.1 If necessary, correct the bure
34、t reading for calibration errors and record the volume of titrant as Vand the temperature ast.14.2 Correct the normality of the sodium hydroxide standard solution for any difference in temperature between time ofstandardization and time of use according to the following equation:N 5Ns10.00014 s 2t!
35、(1)where:N = normality meq/mL(N) of NaOH solution at temperature t during use,Ns = normality meq/mL(N) of NaOH solution at temperature s during standardization,s = temperature of NaOH solution during standardization, andt = temperature of NaOH solution during analysis.14.3 Calculate the total acidit
36、y as % mass (m/m) of sulfuric acid as follows:Sulfuric acid,%mass m/m!5VN30.04904!W 3100 (2)where:V = corrected millilitre of NaOH solution required for titration of the sample,N = meq/mL(N) normality of the NaOH solution, andW = grams of sample used.15. Report15.1 Report the % mass (m/m) of sulfuri
37、c acid to the nearest 0.01 % mass(m/m).16. Precision and Bias16.1 The following criteria should be used for judging the acceptability of results (see Note 5):16.1.1 Repeatability (Single Analyst)The standard deviation for a single determination has been estimated to be 0.069 % mass(m/m) absolute at
38、56 df. The 95 % limit for the difference between two such runs is 0.19 % mass (m/m) absolute.16.1.2 Laboratory Precision (Within-Laboratory, Between-Days VariabilityThe standard deviation of results (each theaverage of duplicates), obtained by the same analyst on different days, has been estimated t
39、o be 0.104 % mass (m/m) absolute at28 df. The 95 % limit for the difference between two such averages is 0.29 % mass (m/m) absolute.16.1.3 Reproducibility (Multilaboratory)The standard deviation of results (each the average of duplicates), obtained byanalysts in different laboratories, has been esti
40、mated to be 0.124 % mass (m/m) absolute at 7 df. The 95 % limit for the differencebetween two such averages is 0.35 % mass (m/m) absolute.NOTE 5These precision estimates are based on an interlaboratory study of analyses performed in 1963 on three samples containing approximately80, 90, and 95 % mass
41、 (m/m) sulfuric acid. One analyst in each of ten laboratories performed duplicate determinations and repeated one day later, fora total of 120 determinations.7 Practice E180 was used in developing these precision estimates.16.2 Since there is no accepted reference material for determining the bias f
42、or measuring the total acidity of sulfuric acid, thebias of this test method has not been determined.7 Details of the interlaboratory study are available from ASTM International Headquarters. Request Supporting data have been filed at ASTM International Headquartersand may be obtained by requesting
43、RR:E15-1047. Contact ASTM Customer Service at serviceastm.org.E223 164BAUM GRAVITY17. Scope17.1 This test method covers the determination of the Baum gravity of concentrated sulfuric acid by means of a glasshydrometer in the range from 57 to 66.2 Baum. The Baum gravity is determined at 15.5C (60F).
44、This test method is notapplicable to readings above 66.2 Baum gravity units.18. Definition18.1 Baum Gravitya unit of density based on specific gravity and defined by the following equation:Baume gravity51452145/sp gr#at 15.5/15.5C 60/60F! (3)19. Summary of Test Method19.1 A sample of sulfuric acid i
45、s placed in a hydrometer cylinder and when the temperature is constant, the Baum gravity isread from the glass hydrometer.20. Significance and Use20.1 The Baum gravity is used to classify various grades of sulfuric acid. This test method is not applicable for accuratedeterminations of the concentrat
46、ion of sulfuric acid.21. Apparatus21.1 Hydrometer,8streamline or torpedo design, precision grade for liquids heavier than water in ranges from 57 to 62 B and63 to 67 B. The total length shall be approximately 305 mm (12 in.) divided to 0.05 B over a 152-mm (6-in.) (approximate)scale and standardized
47、 at 15.5/15.5C (60/60F) with a tolerance of 0.05 B throughout. The modulus is as follows:Be 51452145/sp gr#at 15.5/15.5C 60/60F! (4)Each of the hydrometers shall show on the scale the modulus.21.2 Thermometer, having a range from 2 to + 80C (30 to 180F) and conforming to the requirements for Thermom
48、eter 15C(15F) as prescribed in Specification E1.21.3 Cylinder, Hydrometer, glass, with or without lip, diameter 38 to 40 mm, height 325 to 375 mm.22. Temperature of Test22.1 Baum gravity shall be determined at 15.5 6 0.3C (60 6 0.5F).23. Procedure23.1 Rinse a clean hydrometer cylinder with the sampl
49、e to be tested, add the sample, and adjust the temperature to 15.5 6 0.3C(60 6 0.5F). Place the cylinder in a vertical position in a location free of air currents. Insert the hydrometer in the sample. Pushit down about 3 mm below the level at which it will float and release it. Read the hydrometer when it has come to rest, floatingfreely, and the temperature is 15.5C (60F). The correct reading is that point on the hydrometer scale at which the surface of theliquid cuts the scale. Determine this point by placing
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