1、Designation: D 3645 03An American National StandardStandard Test Methods forBeryllium in Water1This standard is issued under the fixed designation D 3645; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、 number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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:Concentration
3、Range SectionsTest Method AAtomic Absorption,Direct10 to 500 g/L 7 to 16Test Method BAtomic Absorption,Graphite Furnace10 to 50 g/L 17 to 251.2 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 thes
4、e test methods for waters ofuntested matrices.1.3 This standard 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 regul
5、atory limitations prior to use. For specific hazardstatements, see Section 12 and 23.4.2. Referenced Documents2.1 ASTM Standards:D 858 Test Methods for Manganese in Water2D 1068 Test Methods for Iron in Water2D 1129 Terminology Relating to Water2D 1193 Specification for Reagent Water2D 1687 Test Met
6、hods for Chromium in Water2D 1688 Test Methods for Copper in Water2D 1691 Test Methods for Zinc in Water2D 1886 Test Methods for Nickel in Water2D 2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on Water2D 3370 Practices for Sampling Water from Closed
7、 Con-duits2D 3557 Test Methods for Cadmium in Water2D 3558 Test Methods for Cobalt in Water2D 3559 Test Methods for Lead in Water2D 3919 Practice for Measuring Trace Elements in Water byGraphite Furnace Atomic Absorption Spectrophotometry2D 4841 Practice for Estimation of Holding Time for WaterSampl
8、es Containing Organic and Inorganic Constituents2D 5810 Guide for Spiking into Aqueous Samples2D 5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water Analysis33. Terminology3.1 DefinitionsFor definitions of terms used in these testmethods, refer to Terminology
9、D 1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 total recoverable berylliumtotal recoverable beryl-lium relates only to the recoverable forms of beryllium by thesetest methods.4. Significance and Use4.1 These test methods are significant because the concen-tration of beryllium in wat
10、er must be measured accurately inorder 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 AnalyticalReag
11、ents of the American Chemical Society, where suchspecifications are available.4Other grades may be used, pro-vided it is first ascertained that the reagent is sufficiently highin purity to permit its use without lessening the accuracy of thedetermination.5.2 Unless otherwise indicated, reference to
12、water shall beunderstood to mean reagent water conforming to SpecificationD 1193, Type I. Other reagent water types may be usedprovided it is first ascertained that the water is of sufficientlyhigh purity to permit its use without adversely affecting thebias and precision of the test method. Type II
13、 water wasspecified at the time of round robin testing of this test method.1These 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 Jan. 10, 2003. Published January
14、 2003. Originallyapproved in 1978. Last previous edition approved in 2002 as D 3645 02.2Annual Book of ASTM Standards, Vol 11.01.3Annual Book of ASTM Standards, Vol 11.02.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the te
15、sting 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. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.1*A Summary of Changes section appears at the
16、 end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Sampling6.1 Collect the samples in accordance with PracticesD 3370. The holding time for samples may be calculated inaccordance with Practice D 4841.6.2 Preserve
17、 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.TEST METHOD AATOMIC ABSORPTION, DIRECT7. Scope7.1 This test method i
18、s 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, springwater, and untreated wastewater. The information on precisionand bi
19、as 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. Dissolved beryllium is determined by aspirating afiltered sample dir
20、ectly 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 recoverable cadmium (Test Methods D 3557), chromium(Test Methods D 1
21、687), cobalt (Test Methods D 3558), copper(Test Methods D 1688), iron (Test Methods D 1068), lead (TestMethods D 3559), manganese (Test Methods D 858), nickel(Test Methods D 1886), and zinc (Test Methods D 1691).9. Interferences9.1 Aluminum at concentrations greater than 500 g/L hasbeen reported to
22、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 ionization is suppressed by addingcalcium chloride to give a fin
23、al concentration of 900 mg/Lcalcium in all standard and sample solutions.10. Apparatus10.1 Atomic Absorption Spectrophotometer, for use at 234.9nm.NOTE 1The manufacturers instructions should be followed for allinstrument parameters.10.2 Beryllium Hollow Cathode Lamp.10.3 Pressure RegulatorsThe suppl
24、ies 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 1.000 g of beryllium metal in a minimum volume ofHCl (1 + 1) a
25、nd dilute to 1 L. (Beryllium is toxic and thesolution should be prepared in a well-ventilated hood.)NOTE 2Certified beryllium stock solutions are commercially avail-able through chemical supply vendors.11.2 Beryllium Solution, Intermediate (1.00 mL = 100 gBe)Dilute 10.0 mL of the beryllium stock sol
26、ution 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 in a minimum volume of HCl (1 + 1)
27、 and dilute to 1L with water.11.5 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 distilled, an azeotropic mixture isobtained (approximately 6 N HCl). Therefore, whenever concentrated
28、 HClis specified in the preparation of a reagent or in the procedure, use doublethe amount if distilled acid is used.)11.6 Hydrochloric Acid (1 + 1)Mix 1 volume of HCl (spgr 1.19) with 1 volume of water.11.7 Nitric Acid (sp gr 1.42)Concentrated nitric acid(HNO3).NOTE 4If a high reagent blank is obta
29、ined, distill the HNO3or usespectrograde acid.11.8 Nitric Acid (1 + 499)Add 1 volume of HNO3(sp gr1.42) to 499 volumes of water.11.9 Oxidant:11.9.1 Air, which has been passed through a suitable filter toremove oil, water, and other foreign substances, is the oxidantused prior to switching to nitrous
30、 oxide.11.9.2 Nitrous Oxide is the required oxidant.11.10 Fuel:11.10.1 AcetyleneStandard 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 75 psi (517 kPa). (“Prep
31、urified”grade acetylene containing a special proprietary solvent otherthan acetone should 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 step
32、s should be carried out in awell-ventilated hood. Also, the atomic absorption unit shouldbe 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 dilu
33、ting the beryllium standardD3645032solution (11.3) with HNO3(1 + 499). Prepare the standards(100 mL) each time the test is to be performed.13.2 For total recoverable beryllium, add 0.5 mL ofHNO3(sp gr 1.42) and proceed as directed in 14.2-14.6. Fordissolved beryllium, proceed with 13.3.13.3 Add 1.0
34、mL of calcium solution to a 10.0-mL aliquotof each standard and blank solution. Mix thoroughly.13.4 Aspirate the blank and standards and record the instru-ment readings. Aspirate HNO3(1 + 499) between each stan-dard. (The atomic absorption unit should be vented properly.)13.5 Prepare an analytical c
35、urve by plotting the absorbanceversus the standard concentration for each standard on lineargraph paper. Alternatively, use a direct concentration readout ifthe 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 b
36、eryllium is to be determined, start with14.5.14.2 Add 5 mL of HCl (sp gr 1.19) to each sample.14.3 Heat the samples on a steam bath or hot plate until 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 sampl
37、es with high levels of suspended matteror total dissolved solids, the amount of reduction is left to the discretionof the analyst.14.4 Cool and filter the samples through a suitable filter(such as a fine-textured, acid-washed, ashless paper) into100-mL volumetric flasks. Wash the filter paper two or
38、 threetimes with water and adjust to volume.14.5 Add 1.0 mL of calcium solution to a 10.0-mL aliquotof each sample and mix thoroughly.14.6 Aspirate each sample and determine its absorbance orconcentration. Aspirate HNO3(1 + 499) between each sample.15. Calculation15.1 Calculate the concentration of
39、beryllium in eachsample, in micrograms per litre, using the analytical curvedescribed in 13.5.16. Precision and Bias516.1 Based on the round-robin results from seven laborato-ries and ten operators, the following precision and biasstatements can be made:16.1.1 The overall and single-operator precisi
40、on 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 wa
41、ter, lake water, springwater, and untreated wastewater. It is the users responsibilityto ensure the validity of this test method for waters of untestedmatrices.16.3 Precision and bias for this test method conforms toPractice D277777, which was in place at the time ofcollaborative testing. Under the
42、allowances made in 1.4 ofPractice D277798, these precision and bias data do meetexisting requirements for interlaboratory studies of CommitteeD19 test methods.TEST METHOD BATOMIC ABSORPTION,GRAPHITE FURNACE17. Scope17.1 This test method covers the determination of dissolvedand total recoverable bery
43、llium in most waters and wastewa-ters.17.2 This test method is applicable in the range from 10 to50 g/L of beryllium using a 20-L injection. The range can beincreased or decreased by varying the volume of sampleinjected or the instrumental settings. High concentrations maybe diluted but preferably s
44、hould be analyzed by direct-aspiration atomic-absorption spectrophotometry.17.3 This test method has been used successfully withreagent water, lake water, river water, well water, filtered tapwater, and a condensate from a medium Btu coal gasification5Supporting data are available from ASTM Headquar
45、ters. Request RR: D19-1043.TABLE 1 Overall S(T) and Single-Operator (SO) InterlaboratoryPrecision 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 10.3
46、TABLE 2 Precision and Bias, Atomic Absorption, DirectAmountAdded,g/LAmountFound,g/L% BiasStatisticallySignificant (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 yesD3645033process
47、. It is the users responsibility to ensure validity of thistest method to waters of untested matrices.17.4 The analyst is encouraged to consult Practice D 3919for a general discussion of interferences and sample analysisprocedures for graphite furnace atomic absorption spectropho-tometry.18. Summary
48、 of Test Method18.1 Beryllium is determined by an atomic-absorption spec-trophotometer used in conjunction with a graphite furnace. Asample is placed in a graphite tube, evaporated to dryness,charred (pyrolyzed or ashed), and atomized. Since the graphitefurnace uses the sample much more efficiently
49、than flameatomization, the detection of low concentrations of elements insmall sample volumes is possible. Finally, the absorption signalgenerated during atomization is recorded and compared tostandards. A general guide for the application of the graphitefurnace is given in Practice D 3919.18.2 Dissolved beryllium is determined on a filtered thenacidified sample with no pretreatment.18.3 Total recoverable beryllium is determined followingacid digestion and filtration. Because chlorides interfere withfurnace procedures for some metals, the
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