ASTM D3645-2015 Standard Test Methods for Beryllium in Water《水中铍含量的标准试验方法》.pdf

1、Designation: D3645 08D3645 15 An American National StandardStandard Test Methods forBeryllium in Water1This standard is issued under the fixed designation D3645; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revi

2、sion. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope Scope*1.1 These test methods cover the determination of dissolved and total recoverable beryllium in most waters and wastewaters:C

3、oncentrationRange SectionsTest Method AAtomic Absorption, Direct 10 to 500 g/L 7 to 17Test Method BAtomic Absorption, Graphite Furnace 10 to 50 g/L 18 to 26ConcentrationRange SectionsTest Method AAtomic Absorption,Direct10 to 500 g/L 7 to 16Test Method BAtomic Absorption,Graphite Furnace10 to 50 g/L

4、 17 to 251.2 The analyst should direct attention to the precision and bias statements for each test method. It is the users responsibilityto ensure the validity of these test methods for waters of untested matrices.1.3 The values stated in SI units are to be regarded as standard. No other units of m

5、easurement are included in this The valuesgiven in parentheses are mathematical conversions to inch-pound units that are provided for information only and are notconsidered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the r

6、esponsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.For specific hazard statements, see Section 12 and 23.424.4.2. Referenced Documents2.1 ASTM Standards:2D858 Test Methods for Manganese

7、in WaterD1068 Test Methods for Iron in WaterD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD1687 Test Methods for Chromium in WaterD1688 Test Methods for Copper in WaterD1691 Test Methods for Zinc in WaterD1886 Test Methods for Nickel in WaterD2777 Practice for Determination

8、 of Precision and Bias of Applicable Test Methods of Committee D19 on WaterD3370 Practices for Sampling Water from Closed ConduitsD3557 Test Methods for Cadmium in WaterD3558 Test Methods for Cobalt in WaterD3559 Test Methods for Lead in WaterD3919 Practice for Measuring Trace Elements in Water by G

9、raphite Furnace Atomic Absorption SpectrophotometryD4841 Practice for Estimation of Holding Time for Water Samples Containing Organic and Inorganic ConstituentsD5673 Test Method for Elements in Water by Inductively Coupled PlasmaMass Spectrometry1 These test methods are under the jurisdiction of AST

10、M Committee D19 on Water and are the direct responsibility of Subcommittee D19.05 on Inorganic Constituentsin Water.Current edition approved Oct. 1, 2008Feb. 1, 2015. Published October 2008March 2015. Originally approved in 1978. Last previous edition approved in 20032008 asD3645 03.D3645 08. DOI: 1

11、0.1520/D3645-08.10.1520/D3645-15.2 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 Summary page on the ASTM website.This document is not an ASTM

12、 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 be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all

13、 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 of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D5810 Guide

14、 for Spiking into Aqueous SamplesD5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis3. Terminology3.1 DefinitionsDefinitions:For3.1.1 For definitions of terms used in these test methods, refer to Terminology D1129. definitions of terms used in these

15、 testmethods, refer to Terminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 total recoverable berylliumberyllium, ntotal recoverable beryllium relates only a descriptive term relating to therecoverable forms of beryllium by beryllium forms recovered in the acid-digestion proced

16、ure specified in these test methods.4. Significance and Use4.1 These test methods are significant because the concentration of beryllium in water must be measured accurately in order toevaluate potential health and environmental effects.5. Purity of Reagents5.1 Reagent grade chemicals shall be used

17、in all tests. Unless otherwise indicated, it is intended that all reagents shall conformto the specifications of the Committee on Analytical Reagents of the American Chemical Society, where such specifications areavailable.3 Other grades may be used, provided it is first ascertained that the reagent

18、 is sufficiently high in purity to permit its usewithout lessening the accuracy of the determination.5.2 Unless otherwise indicated, reference to water shall be understood to mean reagent water conforming to SpecificationD1193, Type I. Other reagent water types may be used provided it is first ascer

19、tained that the water is of sufficiently high purityto permit its use without adversely affecting the bias and precision of the test method. Type II water was specified at the time ofround robin testing of this test method.6. Sampling6.1 Collect the samples in accordance with Practices D3370.The hol

20、ding time for samples may be calculated in accordance withPractice D4841.6.2 Preserve samples with HNO3 (sp gr 1.42), adding about 2 mL/L, to a pH of 2 or less immediately at the time of collection.If only dissolved beryllium is to be determined, filter the sample, before acidification, through a 0.

21、45-m membrane filter.NOTE 1Alternatively, the pH may be adjusted in the laboratory if the sample is returned within 14 days. However, acid must be added at least 24hours before analysis to dissolve any metals that adsorb to the container walls. This could reduce hazards of working with acids in the

22、field whenappropriate.TEST METHOD AATOMIC ABSORPTION, DIRECT7. Scope7.1 This test method is applicable in the range from 10 to 500 g/Lof beryllium. The range may be extended upward by dilutionof the sample.7.2 The precision and bias data were obtained on reagent water, tap water, salt water, river w

23、ater, lake water, spring water, anduntreated wastewater. The information on precision and bias may not apply to other waters. It is the users responsibility to ensurethe validity of this test method for waters of untested matrices.8. Summary of Test Method8.1 Beryllium is determined by atomic absorp

24、tion spectrophotometry. Dissolved beryllium is determined by aspirating a filteredsample directly with no pretreatment. Total recoverable beryllium in the sample is determined in a portion of the filtrate obtainedafter a hydrochloric-nitric acid digestion of the sample. The same digestion procedure

25、is used to determine total recoverablecadmium (Test Methods D3557), chromium (Test Methods D1687), cobalt (Test Methods D3558), copper (Test Methods D1688),iron (Test Methods D1068), lead (Test Methods D3559), manganese (Test Methods D858), nickel (Test Methods D1886), and zinc(Test Methods D1691).9

26、. Interferences9.1 Aluminum at concentrations greater than 500 g/L has been reported to depress the beryllium absorbance.3 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed bythe American Chem

27、ical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.D3645 1529.2 Sodium and silicon at concentrations in excess of 1000 mg/L have been reported

28、to severely depress the berylliumabsorbance.9.3 Beryllium is slightly ionized in the nitrous oxide-acetylene flame. This ionization is suppressed by adding calcium chlorideto give a final concentration of 900 mg/L calcium in all standard and sample solutions.10. Apparatus10.1 Atomic Absorption Spect

29、rophotometer , Spectrophotometer, for use at 234.9 nm.NOTE 2The manufacturers instructions should be followed for all instrument parameters.10.2 Beryllium Hollow Cathode Lamp.10.3 Pressure RegulatorsThe supplies of oxidants and fuel shall be maintained at pressures somewhat higher than thecontrolled

30、 operating pressure of the instrument by suitable regulators.11. Reagents and Materials11.1 Beryllium Solution, Stock (1.00 mL = 1000 g Be)Dissolve 1.000 g of beryllium metal in a minimum volume of HCl(1 + 1) and dilute to 1 L. (Beryllium is toxic and the solution should be prepared in a well-ventil

31、ated hood.) A purchased metalstock solution of appropriate known purity is also acceptable.NOTE 2Certified beryllium stock solutions are commercially available through chemical supply vendors.11.2 Beryllium Solution, Intermediate (1.00 mL = 100 g Be)Dilute 10.0 mLof the beryllium stock solution to 1

32、00.0 mLwithnitric acid (HNO3, 1 + 499).11.3 Beryllium Solution, Standard (1.00 mL = 1.00 g Be)Dilute 5.00 mL of the beryllium intermediate solution to 500.0 mLwith nitric acid (HNO3, 1 + 499).11.4 Calcium Solution (10 g/L)Dissolve 25 g of calcium carbonate in a minimum volume of HCl (1 + 1) and dilu

33、te to 1 Lwith water.11.5 Filter PaperPurchase suitable filter paper. Typically the filter papers have a pore size of 0.45-m membrane. Materialsuch as fine-textured, acid-washed, ashless paper, or glass fiber paper are acceptable. The user must first ascertain that the filterpaper is of sufficient pu

34、rity to use without adversely affecting the bias and precision of the test method.11.6 Hydrochloric Acid (sp gr 1.19)Concentrated hydrochloric acid (HCl).NOTE 3If a high reagent blank is obtained, distill the HCl or use spectrograde acid. (When HCl is distilled, an azeotropic mixture is obtained(app

35、roximately 6 N HCl). Therefore, whenever concentrated HCl is specified in the preparation of a reagent or in the procedure, use double the amountif distilled acid is used.)11.7 Hydrochloric Acid (1 + 1)Mix 1 volume of HCl (sp gr 1.19) with 1 volume of water. Always add acid to water.11.8 Nitric Acid

36、 (sp gr 1.42)Concentrated nitric acid (HNO3).NOTE 4If a high reagent blank is obtained, distill the HNO3 or use spectrograde acid.11.9 Nitric Acid (1 + 499)Add 1 volume of HNO3 (sp gr 1.42) to 499 volumes of water.11.10 Oxidant:11.10.1 Air, which has been passed through a suitable filter to remove o

37、il, water, and other foreign substances, is the oxidantused prior to switching to nitrous oxide.11.10.2 Nitrous Oxide is the required oxidant.11.11 Fuel:11.11.1 AcetyleneStandard commercially available acetylene is the required fuel. Acetone, always present in acetylenecylinders, can affect analytic

38、al results. The cylinder should be replaced at a gage pressure of 75 psi (517 kPa).517 kPa (75 psi).(“Prepurified” grade acetylene containing a special proprietary solvent other than acetone should not be used with poly (vinylchloride) tubing as weakening of the walls can cause a potentially hazardo

39、us situation.)12. Hazards12.1 Due to the high toxicity of beryllium, all sample preparation and digestion steps should be carried out in a well-ventilatedhood. Also, the atomic absorption unit should be vented as recommended by the manufacturer.13. Standardization13.1 Prepare a blank and at least fo

40、ur standard solutions to bracket the expected beryllium concentration range of the samplesto be analyzed by diluting the beryllium standard solution (11.3) with HNO3 (1 + 499). (1 + 499) (11.9). Analyze at least threeD3645 153working standards containing concentrations of beryllium that bracket the

41、expected sample concentration prior to analysis ofsamples to calibrate the instrument. Prepare the standards (100 mL) each time the test is to be performed.performed or asdetermined by Practice D4841.13.2 For total recoverable beryllium, add 0.5 mL of HNO3 (sp gr 1.42) (11.8) and proceed as directed

42、 in 14.2 14.6. Fordissolved beryllium, proceed with 13.3.13.3 Add 1.0 mL of calcium solution (11.4) to a 10.0-mL aliquot of each standard and blank solution. Mix thoroughly.13.4 Aspirate the blank and standards and record the instrument readings. Aspirate HNO3 (1 + 499) between each standard.(The at

43、omic absorption unit should be vented properly.)13.5 Prepare an analytical curve by plotting the absorbance versus the standard concentration for each standard on linear graphpaper. Alternatively, use a direct concentration readout if the instrument is so equipped.14. Procedure14.1 Measure 100.0 mL

44、of a well-mixed acidified sample into a 150-mL beaker.NOTE 5If only dissolved beryllium is to be determined, start with 14.5.14.2 Add 5 mL of HCl (sp gr 1.19) (11.6) to each sample.14.3 Heat the samples on a steam bath or hot plate until the volume has been reduced to 15 or 20 mL, making certain tha

45、t thesamples do not boil. (Perform in a well-ventilated hood.)NOTE 6For brines and samples with high levels of suspended matter or total dissolved solids, the amount of reduction is left to the discretion of theanalyst.NOTE 7Many laboratories have found block digestion systems a useful way to digest

46、 samples for trace metals analysis. Systems typically consist ofeither a metal or graphite block with wells to hold digestion tubes. The block temperature controller must be able to maintain uniformity of temperatureacross all positions of the block. For trace metals analysis, the digestion tubes sh

47、ould be constructed of polypropylene and have a volume accuracy ofat least 0.5 %. All lots of tubes should come with a certificate of analysis to demonstrate suitability for their intended purpose.14.4 Cool and filter the samples through a suitable filter (11.5) (such as a fine-textured, acid-washed

48、, ashless paper) into 100-mLvolumetric flasks. Wash the filter paper two or three times with water and adjust to volume.14.5 Add 1.0 mL of calcium solution (11.4) to a 10.0-mL aliquot of each sample and mix thoroughly.14.6 Aspirate each sample and determine its absorbance or concentration. Aspirate

49、HNO3 (1 + 499) between each sample.15. Calculation15.1 Calculate the concentration of beryllium in each sample, in micrograms per litre, using the analytical curve described in13.5.16. Precision and Bias416.1 Based on the round-robin results from seven laboratories and ten operators, the following precision and bias statementscan be made:16.1.1 The overall and single-operator precision of this test method, within its designated range for reagent water and selectedwater matrices, varies with the quantity tested as shown in Table 1.16.