ANSI ASTM D3645-2015 Standard Test Methods for Beryllium in Water.pdf

1、Designation: D3645 15Standard 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 revision. A number in parentheses indicate

2、s the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These test methods cover the determination of dissolvedand total recoverable beryllium in most waters and wastewa-ters:ConcentrationRange SectionsTest Method AAtomi

3、c Absorption,Direct10 to 500 g/L 7 to 17Test Method BAtomic Absorption,Graphite Furnace10 to 50 g/L 18 to 261.2 The analyst should direct attention to the precision andbias statements for each test method. It is the users responsi-bility to ensure the validity of these test methods for waters ofunte

4、sted matrices.1.3 The values stated in SI units are to be regarded asstandard. The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.1.4 This standard does not purport to address all of thesafety concer

5、ns, 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. For specific hazardstatements, see Section 12 and 24.4.2. Referenced Documents2.1 A

6、STM Standards:2D858 Test Methods for Manganese 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

7、Nickel in WaterD2777 Practice for Determination of Precision and Bias ofApplicable 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 Pract

8、ice for Measuring Trace Elements in Water byGraphite Furnace Atomic Absorption SpectrophotometryD4841 Practice for Estimation of Holding Time for WaterSamples Containing Organic and Inorganic ConstituentsD5673 Test Method for Elements in Water by InductivelyCoupled PlasmaMass SpectrometryD5810 Guide

9、 for Spiking into Aqueous SamplesD5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water Analysis3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in these test methods,refer to Terminology D1129.3.2 Definitions of Terms Specific to This Standard:

10、3.2.1 total recoverable beryllium, na descriptive termrelating to the beryllium forms recovered in the acid-digestionprocedure specified in these test methods.4. Significance and Use4.1 These test methods are significant because the concen-tration of beryllium in water must be measured accurately in

11、order to evaluate potential health and environmental effects.5. Purity of Reagents5.1 Reagent grade chemicals shall be used in all tests.Unless otherwise indicated, it is intended that all reagents shallconform to the specifications of the Committee on AnalyticalReagents of the American Chemical Soc

12、iety, where such1These test methods are under the jurisdiction of ASTM Committee D19 onWater and are the direct responsibility of Subcommittee D19.05 on InorganicConstituents in Water.Current edition approved Feb. 1, 2015. Published March 2015. Originallyapproved in 1978. Last previous edition appro

13、ved in 2008 as D3645 08. DOI:10.1520/D3645-15.2For referenced ASTM standards, visit the 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.*A Summary of C

14、hanges section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the

15、Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1specifications are available.3Other grades may be used, pro-vided it is first ascertained that the reagent is sufficien

16、tly highin purity to permit its use without lessening the accuracy of thedetermination.5.2 Unless otherwise indicated, reference to water shall beunderstood to mean reagent water conforming to SpecificationD1193, Type I. Other reagent water types may be usedprovided it is first ascertained that the

17、water is of sufficientlyhigh purity to permit its use without adversely affecting thebias and precision of the test method. Type II water wasspecified at the time of round robin testing of this test method.6. Sampling6.1 Collect the samples in accordance with PracticesD3370. The holding time for sam

18、ples may be calculated inaccordance with Practice D4841.6.2 Preserve samples with HNO3(sp gr 1.42), adding about2 mL/L, to a pH of 2 or less immediately at the time ofcollection. If only dissolved beryllium is to be determined,filter the sample, before acidification, through a 0.45-mmembrane filter.

19、NOTE 1Alternatively, the pH may be adjusted in the laboratory if thesample is returned within 14 days. However, acid must be added at least24 hours before analysis to dissolve any metals that adsorb to the containerwalls. This could reduce hazards of working with acids in the field whenappropriate.T

20、EST METHOD AATOMIC ABSORPTION, DIRECT7. Scope7.1 This test method is applicable in the range from 10 to500 g/L of beryllium. The range may be extended upward bydilution of the sample.7.2 The precision and bias data were obtained on reagentwater, tap water, salt water, river water, lake water, spring

21、water, and untreated wastewater. The information on precisionand bias may not apply to other waters. It is the usersresponsibility to ensure the validity of this test method forwaters of untested matrices.8. Summary of Test Method8.1 Beryllium is determined by atomic absorption spectro-photometry. D

22、issolved beryllium is determined by aspirating afiltered sample directly with no pretreatment. Total recoverableberyllium in the sample is determined in a portion of the filtrateobtained after a hydrochloric-nitric acid digestion of thesample. The same digestion procedure is used to determinetotal r

23、ecoverable cadmium (Test Methods D3557), chromium(Test Methods D1687), cobalt (Test Methods D3558), copper(Test Methods D1688), iron (Test Methods D1068), lead (TestMethods D3559), manganese (Test Methods D858), nickel(Test Methods D1886), and zinc (Test Methods D1691).9. Interferences9.1 Aluminum a

24、t concentrations greater than 500 g/L hasbeen reported to depress the beryllium absorbance.9.2 Sodium and silicon at concentrations in excess of 1000mg/L have been reported to severely depress the berylliumabsorbance.9.3 Beryllium is slightly ionized in the nitrous oxide-acetylene flame. This ioniza

25、tion is suppressed by addingcalcium chloride to give a final concentration of 900 mg/Lcalcium in all standard and sample solutions.10. Apparatus10.1 Atomic Absorption Spectrophotometer, for use at 234.9nm.NOTE 2The manufacturers instructions should be followed for allinstrument parameters.10.2 Beryl

26、lium Hollow Cathode Lamp.10.3 Pressure RegulatorsThe supplies of oxidants andfuel shall be maintained at pressures somewhat higher than thecontrolled operating pressure of the instrument by suitableregulators.11. Reagents and Materials11.1 Beryllium Solution, Stock (1.00 mL = 1000 g Be)Dissolve 1.00

27、0 g of beryllium metal in a minimum volume ofHCl (1 + 1) and dilute to 1 L. (Beryllium is toxic and thesolution should be prepared in a well-ventilated hood.) Apurchased metal stock solution of appropriate known purity isalso acceptable.11.2 Beryllium Solution, Intermediate (1.00 mL = 100 gBe)Dilute

28、 10.0 mL of the beryllium stock solution to 100.0mL with nitric acid (HNO3, 1 + 499).11.3 Beryllium Solution, Standard (1.00 mL = 1.00 gBe)Dilute 5.00 mL of the beryllium intermediate solution to500.0 mL with nitric acid (HNO3, 1 + 499).11.4 Calcium Solution (10 g/L)Dissolve 25 g of calciumcarbonate

29、 in a minimum volume of HCl (1 + 1) and dilute to 1L with water.11.5 Filter PaperPurchase suitable filter paper. Typicallythe filter papers have a pore size of 0.45-m membrane.Material such as fine-textured, acid-washed, ashless paper, orglass fiber paper are acceptable. The user must first ascertai

30、nthat the filter paper is of sufficient purity to use withoutadversely affecting the bias and precision of the test method.11.6 Hydrochloric Acid (sp gr 1.19)Concentrated hydro-chloric acid (HCl).NOTE 3If a high reagent blank is obtained, distill the HCl or usespectrograde acid. (When HCl is distill

31、ed, an azeotropic mixture isobtained (approximately 6 N HCl). Therefore, whenever concentrated HClis specified in the preparation of a reagent or in the procedure, use doublethe amount if distilled acid is used.)11.7 Hydrochloric Acid (1+1)Mix 1 volume of HCl (spgr 1.19) with 1 volume of water. Alwa

32、ys add acid to water.11.8 Nitric Acid (sp gr 1.42)Concentrated nitric acid(HNO3).3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for Lab

33、oratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.D3645 152NOTE 4If a high reagent blank is obtained, distill the HNO3or usespectrograde acid.11.9 Nitric Acid (1 + 499)Add 1 volume of HN

34、O3(sp gr1.42) to 499 volumes of water.11.10 Oxidant:11.10.1 Air, which has been passed through a suitable filterto remove oil, water, and other foreign substances, is theoxidant used prior to switching to nitrous oxide.11.10.2 Nitrous Oxide is the required oxidant.11.11 Fuel:11.11.1 AcetyleneStandar

35、d commercially available acety-lene is the required fuel. Acetone, always present in acetylenecylinders, can affect analytical results. The cylinder should bereplaced at a gage pressure of 517 kPa (75 psi). (“Prepurified”grade acetylene containing a special proprietary solvent otherthan acetone shou

36、ld not be used with poly (vinyl chloride)tubing as weakening of the walls can cause a potentiallyhazardous situation.)12. Hazards12.1 Due to the high toxicity of beryllium, all samplepreparation and digestion steps should be carried out in awell-ventilated hood. Also, the atomic absorption unit shou

37、ldbe vented as recommended by the manufacturer.13. Standardization13.1 Prepare a blank and at least four standard solutions tobracket the expected beryllium concentration range of thesamples to be analyzed by diluting the beryllium standardsolution (11.3) with HNO3(1 + 499) (11.9). Analyze at leastt

38、hree working standards containing concentrations of berylliumthat bracket the expected sample concentration prior to analysisof samples to calibrate the instrument. Prepare the standards(100 mL) each time the test is to be performed or as determinedby Practice D4841.13.2 For total recoverable beryll

39、ium, add 0.5 mL ofHNO3(sp gr 1.42) (11.8) and proceed as directed in 14.2 14.6. For dissolved beryllium, proceed with 13.3.13.3 Add 1.0 mL of calcium solution (11.4) to a 10.0-mLaliquot of each standard and blank solution. Mix thoroughly.13.4 Aspirate the blank and standards and record the instru-me

40、nt readings. Aspirate HNO3(1 + 499) between each stan-dard. (The atomic absorption unit should be vented properly.)13.5 Prepare an analytical curve by plotting the absorbanceversus the standard concentration for each standard on lineargraph paper. Alternatively, use a direct concentration readout if

41、the instrument is so equipped.14. Procedure14.1 Measure 100.0 mL of a well-mixed acidified sampleinto a 150-mL beaker.NOTE 5If only dissolved beryllium is to be determined, start with14.5.14.2 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

42、 thevolume has been reduced to 15 or 20 mL, making certain thatthe samples do not boil. (Perform in a well-ventilated hood.)NOTE 6For brines and samples with high levels of suspended matteror total dissolved solids, the amount of reduction is left to the discretionof the analyst.NOTE 7Many laborator

43、ies have found block digestion systems auseful way to digest samples for trace metals analysis. Systems typicallyconsist of either a metal or graphite block with wells to hold digestiontubes. The block temperature controller must be able to maintain unifor-mity of temperature across all positions of

44、 the block. For trace metalsanalysis, the digestion tubes should be constructed of polypropylene andhave a volume accuracy of at least 0.5 %. All lots of tubes should comewith a certificate of analysis to demonstrate suitability for their intendedpurpose.14.4 Cool and filter the samples through a su

45、itable filter(11.5) (such as a fine-textured, acid-washed, ashless paper) into100-mL volumetric flasks. Wash the filter paper two or threetimes with water and adjust to volume.14.5 Add 1.0 mL of calcium solution (11.4) to a 10.0-mLaliquot of each sample and mix thoroughly.14.6 Aspirate each sample a

46、nd determine its absorbance orconcentration. Aspirate HNO3(1 + 499) between each sample.15. Calculation15.1 Calculate the concentration of beryllium in eachsample, in micrograms per litre, using the analytical curvedescribed in 13.5.TABLE 1 Overall S(T) and Single-Operator (SO) InterlaboratoryPrecis

47、ion for Beryllium by Flame AAS, Test Method AReagent WaterConcentration (X), g/L 15.4 211.0 444.8ST2.7 10.8 21.3SO1.2 4.4 11.9Natural WaterConcentration (X), g/L 16.9 214.7 444.4ST2.9 7.7 19.2SO2.2 5.4 10.3TABLE 2 Precision and Bias, Atomic Absorption, DirectAmountAdded,g/LAmountFound,g/L% BiasStati

48、sticallySignificant (95 %Confidence Level)Reagent Water, Type II16 15.4 3.75 no220 211.0 4.09 yes460 444.8 3.30 yesSelected Water Matrices16 16.9 + 5.60 no220 214.7 2.41 yes460 444.4 3.39 yesD3645 15316. Precision and Bias416.1 Based on the round-robin results from seven laborato-ries and ten operat

49、ors, the following precision and biasstatements can be made:16.1.1 The overall and single-operator precision of this testmethod, within its designated range for reagent water andselected water matrices, varies with the quantity tested asshown in Table 1.16.1.2 The bias of this test method is listed in Table 2.16.2 The precision and bias data were obtained on reagentwater, tap water, salt water, river water, lake water, springwater, and untreated wastewater. It is the users responsibilityto ensure the validity of this test method for wa