ASTM E534-1998(2003) Standard Test Methods for Chemical Analysis of Sodium Chloride《氯化钠化学分析的试验方法》.pdf

1、Designation: E 534 98 (Reapproved 2003)Standard Test Methods forChemical Analysis of Sodium Chloride1This standard is issued under the fixed designation E 534; 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover the chemical analyses usuallyrequired for sodium chloride.1.2 The analytical procedures appear in the f

3、ollowing sec-tions:SectionSample Preparation 5 to 9Moisture 10 to 16Water Insolubles 17 to 24Calcium and Magnesium 25 to 31Sulfate 32 to 38Reporting of Analyses 39 to 411.3 The values stated in SI units are to be regarded as thestandard.1.4 This standard does not purport to address all of thesafety

4、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.1.5 Review the current material safety data sheets (MSDS)for detailed informat

5、ion concerning toxicity, first-aid proce-dures, handling, and safety precautions.2. Referenced Documents2.1 ASTM Standards:D 1193 Specification for Reagent Water2E 180 Practice for Determining the Precision of ASTMMethods for Analysis and Testing of Industrial Chemicals3E 200 Practice for Preparatio

6、n, Standardization, and Stor-age of Standard and Reagent Solutions for ChemicalAnalysis33. Significance and Use3.1 Sodium chloride occurs in nature in almost unlimitedquantities. It is a necessary article of diet as well as the sourcefor production of many sodium compounds and chlorine. Themethods l

7、isted in 1.2 provide procedures for analyzing sodiumchloride to determine if it is suitable for its intended use.4. Reagents4.1 Purity of ReagentsUnless otherwise indicated, it isintended that all reagents should conform to the specificationsof the Committee on Analytical Reagents of the AmericanChe

8、mical Society, where such specifications are available.44.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean Type II or III reagentwater conforming to Specification D 1193.SAMPLE PREPARATION5. Scope5.1 This test method covers preparation of a sample that will

9、be as representative as possible of the entire bulk quantity. Theresults of any analysis pertain only to the sample used.6. Apparatus6.1 Coarse Grinder.6.2 High-Speed Blender.6.3 Oven.6.4 Riffle Sampler.6.5 Scale.7. Reagents7.1 Hydrochloric Acid, Standard 1 N HClPrepare andstandardize in accordance

10、with Practice E 200.8. Rock and Solar Salt Stock Solutions8.1 Mix and split sample to 500 g, using the riffle sampler.8.2 If sample appears wet, dry at 110C for 2 h.8.3 Grind the sample to 8 mesh in the coarse grinder.8.4 Mix ground sample well and weigh out a 25.0-grepresentative portion for rock s

11、alt or 50.0 g for solar salt.8.5 Place 200 mL of water in the high-speed blender andstart at low speed.8.6 Slowly add the salt sample to the high-speed blenderand blend for 5 min.8.7 Test for water insolubles as described in Sections 17-24.1These test methods are under the jurisdiction of ASTM Commi

12、ttee E15 onIndustrial and Specialty Chemicals and are under the direct responsibility ofSubcommittee E15.02 on Product Standards.Current edition approved Apr. 10, 2003. Published May 2003. Originallyapproved in 1975. Last previous edition approved in 1998 as E 534 98.2Annual Book of ASTM Standards,

13、Vol 11.01.3Annual Book of ASTM Standards, Vol 15.05.4Reagent 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., P

14、oole, Dorset, U.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.8.8 Save filtrate from water insolubles test and d

15、ilute in avolumetric flask to 1 L with water as a stock solution forsubsequent analyses.9. Evaporated and Purified Salt Stock Solutions9.1 Mix and split the sample to 100 g for evaporated salt, or200 g for purified evaporated salt.9.2 Transfer to a 1-L volumetric flask.9.3 Add 800 mL of water and al

16、low the salt to dissolve.9.4 Add 2 mL of concentrated HCl to dissolve any waterinsoluble calcium salts, particularly calcium carbonate.9.5 Dilute to volume with water and use as a stock solutionfor subsequent analyses.MOISTURE10. Scope10.1 This test method determines free moisture in the saltover a

17、concentration range from 0.00 to 0.04 %. It does notdetermine occluded moisture trapped within the salt crystals.The procedure is based on weight loss after a sample is heatedto volatize moisture.11. Apparatus11.1 Analytical Balance.11.2 Desiccator.11.3 Oven.12. Procedure, Rock and Solar Salt12.1 We

18、igh 100 g of salt to the nearest 0.05 g into apreviously dried and tared moisture dish.12.2 Dry at 110C for 2 h.12.3 Cool in a desiccator and weigh.13. Procedure, Evaporated and Purified Evaporated Salt13.1 Weigh 20 g of salt to the nearest 0.001 g into apreviously dried and weighed glass weighing b

19、ottle and cover.13.2 Dry at 110C for 2 h.13.3 Cool in a desiccator, replace cover, and weigh.14. Calculation14.1 Calculate the percentage of moisture as follows:moisture, weight % 5AB3 100 (1)where:A = loss of weight on drying, g, andB = weight of sample, g.15. Report15.1 Report the moisture content

20、 to the nearest 0.001 %.16. Precision and Bias16.1 The following criteria should be used in judging theacceptability of results (Note 1):16.1.1 Repeatability (Single Analyst)The standard devia-tion for a single determination has been estimated to be thepercent absolute values shown in Table 1 at the

21、 indicateddegrees of freedom. The 95 % limit for the difference betweentwo such runs is the percent absolute values in Table 1.16.1.2 Laboratory precision (Within-Laboratory, Between-Days Variability)The standard deviation of results (each theaverage of duplicates), obtained by the same analyst ondi

22、fferent days, has been estimated to be the percent absolutevalues shown in Table 1 at the indicated degrees of freedom.The 95 % limit for the difference between two such averages isthe percent absolute values in Table 1.16.1.3 Reproducibility (Multilaboratory)The standard de-viation of results (each

23、 the average of duplicates), obtained byanalysts in different laboratories, has been estimated to bepercent absolute values shown in Table 1. The 95 % limit forthe difference between two such averages is the percentabsolute values in Table 1.NOTE 1The preceding precision statements are based on an i

24、nterlabo-ratory study performed around 1975 on five samples of sodium chloridecontaining covering the ranges of moisture in Table 1. One analyst in eachof ten laboratories performed duplicate determinations and repeated themon a second day.5Practice E 180 was used in developing these precisionestima

25、tes.16.2 BiasThe bias of this test method has not beendetermined due to the unavailability of suitable referencematerials.WATER INSOLUBLES17. Scope17.1 This gravimetric method determines only the amountof insolubles present in sodium chloride which will notdissolve in water.18. Apparatus18.1 Analyti

26、cal Balance.18.2 Desiccator.18.3 Magnetic Stirrer with Stirring Bar.18.4 Parabella Filter Funnel Assembly,61000-mL, or itsequivalent with 0.3-m glass fiber filter disk.5Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: E151052.6Fi

27、sher Scientific No. 9-730-200 has been found satisfactory.TABLE 1 Precision for Moisture MethodRepeatability Laboratory Precision ReproducibilityLevel, %StandardDeviation, %Degrees ofFreedom95 % Limit, % StandardDeviation, %Degrees ofFreedom95 % Limit, % StandardDeviation, %Degrees ofFreedom95 % Lim

28、it, %0.003 to0.0040.0014 36 0.004 0.00223 18 0.006 0.00322 8 0.0090.025 to0.0350.0071 60 0.02 0.00428 30 0.01 0.0138 9 0.04E 534 98 (2003)219. Reagents19.1 Silver Nitrate, Standard Solution, 0.1 N AgNO3Prepare and standardize in accordance with Practice E 200.20. Procedure, Rock and Solar Salts20.1

29、Transfer a sample prepared in accordance with 8.1 to8.6 to a 1-L Erlenmeyer flask, washing out the blender with100 mL of water. Add 300 mL of water to give a total of 600mL of water added.20.2 Stir on a magnetic stirrer for 1 h. Adjust the stirrerspeed to give maximum agitation without danger of los

30、ing anysample due to splashing. Place a beaker over top of the flaskwhile stirring.20.3 Filter the solution by vacuum through a previouslydried (110C for 1 h) and accurately weighed filter disk usingthe Parabella funnel. Transfer all insolubles to the paper andwash free of chlorides with water until

31、 the filtrate shows noturbidity when tested with 0.1 N AgNO3solution.20.4 Dilute filtrate and washings to 1 L with water involumetric flask.20.5 Dry the filter disk at 110C for 1 h.20.6 Cool in a desiccator and weigh the disk on an analyti-cal balance.20.7 Save the filtrate for subsequent analyses.2

32、1. Procedure, Evaporated and Purified Evaporated Salts21.1 Place a well mixed sample in a 2-L beaker. Use 100-gsample for evaporated or 200 g for purified evaporated salt.21.2 Add 750 mL of water.21.3 Mix with a mechanical stirrer until solution is com-plete.21.4 Filter the solution by vacuum throug

33、h a previouslydried (110C for 1 h) and accurately weighed filter disk usingthe Parabella funnel. Transfer all insolubles to the paper andwash free of chlorides with water until the filtrate shows noturbidity when tested with 0.1 N AgNO3solution.21.5 Dry the filter disk at 110C for 1 h.21.6 Cool in a

34、 desiccator and weigh on an analyticalbalance.21.7 Dilute the filtration and washings to 1 L with water ina volumetric flask and reserve for subsequent analyses.22. Calculation22.1 Calculate the percentage of water insolubles as fol-lows:insolubles, weight % 5AB3 100 (2)where:A = increase in weight

35、of filter disk, g, andB = sample weight, g.23. Report23.1 Report the percentage of water insolubles to the nearestpercentage shown as follows:Range, % Report to, %0.002 to 0.005 0.0010.01 to 0.04 0.010.15 to 0.35 0.0124. Precision and Bias24.1 The following criteria should be used in judging theacce

36、ptability of results (Note 2):24.1.1 Repeatability (Single Analyst)The coefficient ofvariation for a single determination has been estimated to bethe percent relative values shown in Table 2 at the indicateddegrees of freedom. The 95 % limit for the difference betweentwo such runs is percent relativ

37、e values shown in Table 2.24.1.2 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 23.5 % relative at 57df. The 95 % limit for the differen

38、ce between two suchaverages is 66 % relative.24.1.3 Reproducibility (Multilaboratory)The coefficientof variation of results (each the average of duplicates), ob-tained by analysts in different laboratories, has been estimatedto be percent relative values shown in Table 2 at the indicateddegrees of f

39、reedom. The 95 % limit for the difference betweentwo such averages is percent relative values shown in Table 2.NOTE 2The preceding precision statements are based on an interlabo-ratory study performed around 1975 on six samples of sodium chloridecovering the ranges of water insolubles in Table 2. On

40、e analyst in each often laboratories performed duplicate determinations and repeated them ona second day.5Practice E 180 was used in developing these precisionestimates.24.2 BiasThe bias of this test method has not beendetermined due to the unavailablility of suitable referencematerials.CALCIUM AND

41、MAGNESIUM25. Scope25.1 This test method covers the EDTA titrimetric determi-nation of calcium and magnesium and the EDTA titrimetricdetermination of calcium. The magnesium content is deter-mined by difference.26. Apparatus26.1 Magnetic Stirrer with Stirring Bar.TABLE 2 Precision for Water Insolubles

42、 MethodRepeatability ReproducibilityLevel, %Coefficient of Variation,% relativeDegreesofFreedom95 % Limit, % relativeCoefficient of Variation,% RelativeDegreesofFreedom95 % Limit, % relative0.002 to 0.005 22.0 20 62 91.7 9 2570.01 to 0.04 21.9 18 61 42.2 8 1180.15 to 0.35 22.0 20 62 20.5 9 57E 534 9

43、8 (2003)327. Reagents27.1 Eriochrome Black T Indicator Solution, HydroxyNaphthol Blue, or its equivalent.27.2 Murexide (Ammonium Purpurate) Indicator Solution,or its equivalent.27.3 EDTA Standard Solution (1 mL = 0.400 mgcalcium)Dissolve 4.0 g of disodium dihydrogen ethylenediaminetetraacetate (EDTA

44、) in 1 L of water. Standardize thissolution against a standard calcium solution prepared bydissolving 1.000 g of CaCO3and 2 mL of HCl in water anddiluting to 1 L with water in a volumetric flask. Obtain an exactfactor for the EDTA solution. This factor is equal to themilligrams of calcium equivalent

45、 to 1.00 mL of EDTA solution.See Practice E 200.factor 5WV(3)where:W = calcium in aliquot, mg, andV = EDTA solution required for titration, mL.27.4 Ammonium ChlorideAmmonium HydroxideSolutionAdd 67.5 g of ammonium chloride (NH4Cl) to 570mL of ammonium hydroxide (NH4OH) contained in a 1-Lvolumetric f

46、lask. Reserve this solution for use as described in27.6 and 27.7.27.5 Potassium Cyanide Solution (50 g/L)Dissolve 50 gof potassium cyanide (KCN) in water and dilute to 1 L withwater. Store in a borosilicate glass bottle. (WarningPotassium cyanide is extremely poisonous.)27.6 Magnesium Sulfate Soluti

47、on (2.5 g/L)Dissolve 2.5 gof MgSO47H2O in water and dilute to volume with water in a1-L volumetric flask. Determine the volume of EDTA solutionequivalent to 50 mL of MgSO4solution as follows: Pipet 50mL of MgSO4solution into a 400-mL beaker. Add 200 mL ofwater and 2 mL of NH4Cl:NH4OH solution (27.4)

48、. Add 1 mLof KCN solution and a sufficient amount of Eriochrome BlackT Indicator solution or its equivalent. Titrate the solution withEDTA solution while stirring with a magnetic stirrer to the trueblue end point. This gives the volume of EDTA solutionequivalent to 50.0 mL of MgSO4solution.27.7 Buff

49、er SolutionPipet 50 mL of MgSO4solution intothe volumetric flask containing the remaining NH4ClNH4OHsolution (27.4). Add the exact volume of EDTA solutionequivalent to 50 mL of the MgSO4solution. Dilute to 1 L withwater. Store the solution in a polyethylene bottle.27.8 Potassium Hydroxide Solution (600 g/L)Dissolve150 g of potassium hydroxide (KOH) in 250 mL of water. Cooland store in a polyethylene bottle.28. Procedure28.1 Using Table 3 as a guide, pipet two aliquots of stocksolution into 400-mL beakers to give a titer between 2 and 10mL of standard