1、Designation: D 4382 02 (Reapproved 2007)e1Standard Test Method forBarium in Water, Atomic Absorption Spectrophotometry,Graphite Furnace1This standard is issued under the fixed designation D 4382; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.e1NOTESection 12.5 was updated editorially in September 2007.1. Scope1.1 This test method covers the det
3、ermination of dissolvedand total recoverable barium in most waters and wastewaters.1.2 This test method was evaluated in the range from 33.5 to132 g/L of barium. The range can be increased or decreasedby varying the volume of sample injected or the instrumentalsettings. High concentrations may be di
4、luted but preferablyshould be analyzed by direct aspiration atomic absorptionspectrophotometry.1.3 This test method has been used successfully with wastetreatment plant effluent water, lake water, filtered tap water,and well water. It is the responsibility of the analyst todetermine the suitability
5、of the test method for other matrices.1.4 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 regulatory li
6、mitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 858 Test Methods for Manganese in WaterD 1068 Test Methods for Iron in WaterD 1129 Terminology Relating to WaterD 1193 Specification for Reagent WaterD 1687 Test Methods for Chromium in WaterD 1688 Test Methods for Copper in WaterD
7、1886 Test Methods for Nickel in WaterD 2777 Practice for Determination of Precision and Bias ofApplicable Test Methods of Committee D19 on WaterD 2972 Test Methods for Arsenic in WaterD 3373 Test Method for Vanadium in WaterD 3557 Test Methods for Cadmium in WaterD 3558 Test Methods for Cobalt in Wa
8、terD 3559 Test Methods for Lead in WaterD 3859 Test Methods for Selenium in WaterD 3866 Test Methods for Silver in WaterD 3919 Practice for Measuring Trace Elements in Water byGraphite Furnace Atomic Absorption SpectrophotometryD 4691 Practice for Measuring Elements in Water by FlameAtomic Absorptio
9、n SpectrophotometryD 4841 Practice for Estimation of Holding Time for WaterSamples Containing Organic and Inorganic ConstituentsD 5810 Guide for Spiking into Aqueous SamplesD 5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water Analysis3. Terminology3.1 Definit
10、ions:3.1.1 For definitions of terms used in this test method, referto Terminology D 1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 total recoverable bariuman arbitrary analytical termrelating to the recoverable forms of barium that are determin-able by the digestion method which is in
11、cluded in this testmethod.4. Summary of Test Method4.1 Barium is determined by an atomic absorption spectro-photometer used in conjunction with a graphite furnace. Asample is placed in a graphite tube, evaporated to dryness,charred (pyrolyzed or ashed), and atomized. The absorptionsignal produced du
12、ring atomization may be recorded andcompared with values obtained from standards that have beencarried through the same process. This facilitates interpolationof the level of barium in the solution being analyzed. Since thegraphite furnace uses the sample much more efficiently thanflame atomization,
13、 the detection of low concentrations in smallsample volumes is possible.NOTE 1The same graphite furnace procedure may be applicable todetermination of arsenic (see Test Methods D 2972), cadmium (see Test1This test method is under the jurisdiction of ASTM Committee D19 on Waterand is the direct respo
14、nsibility of Subcommittee D19.05 on Inorganic Constituentsin Water.Current edition approved Aug. 1, 2007. Published September 2007. Originallyapproved in 1984. Last previous edition approved in 2002 as D 4382 95.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Cus
15、tomer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Methods D 3557), chromium (see Tes
16、t Methods D 1687), cobalt (see TestMethods D 3558), copper (see Test Methods D 1688), iron (see TestMethods D 1068), lead (see Test Methods D 3559), manganese (see TestMethods D 858), nickel (see Test Methods D 1886), selenium (see TestMethods D 3859), silver (see Test Methods D 3866), and vanadium
17、(seeTest Method D 3373).4.2 Dissolved barium is determined on a sample filteredthrough a 0.45-m membrane filter. The definition of dissolvedbarium is arbitrary since very fine crystals of barium sulfatemay pass through the membrane filter.4.3 Total recoverable barium is determined following aciddige
18、stion and filtration. Because chlorides interfere with fur-nace procedures for some metals, the use of hydrochloric acidin any digestion or solubilization step is to be avoided. Ifsuspended material is not present, this digestion and filtrationmay be omitted. The holding time for the samples may bec
19、alculated in accordance with Practice D 4841.5. Significance and Use5.1 Barium ranks about sixth in order of abundance innature; however, it is normally found in only trace quantities indrinking water. Consumption, inhalation, or absorption of 500to 600 mg is considered fatal to human beings.3Lower
20、levelsmay result in disorders of the heart, blood vessels, and nerves.The drinking water standards set the maximum contaminantlevel for barium as 2 mg barium/L.6. Interferences6.1 For a complete discussion on general interferences withfurnace procedures, refer to Practice D 3919.7. Apparatus7.1 Atom
21、ic Absorption Spectrophotometer, for use at 553.6nm with background correction. A general guide for flameatomic absorption applications is given in Practice D 4691.NOTE 2A wavelength other than 553.6 nm may be used if it has beendetermined to be suitable. At high concentration, greater linearity may
22、 beobtained by using a less sensitive wavelength.NOTE 3The manufacturers instructions should be followed for allinstrumental parameters.7.2 Barium Light SourceBarium hollow-cathode lamp. Asingle-element lamp is preferred. Multielement lamps contain-ing calcium are not recommended.7.3 Graphite Furnac
23、e, capable of reaching temperaturessufficient to atomize the element of interest.7.4 Graphite Tubes, compatible with furnace device. Toeliminate the formation of carbides, pyrolytically coated graph-ite tubes are recommended.7.5 Data Storage and Reduction DevicesComputer andmicroprocessor controlled
24、 devices, or a strip chart recorder,shall be utilized for data collection, storage, reduction, andproblem recognition (drift, incomplete atomization, changes insensitivity, etc.).7.6 Automatic Sampling accessory should be used, if avail-able.8. Reagents and Materials8.1 Purity of ReagentsReagent gra
25、de chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.4Other grades may beused, provided it is first asc
26、ertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.8.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water conformingto Specification D 1193, Type I. Other reagent water type
27、s maybe used, provided it is first ascertained that the water is ofsufficiently high purity to permit its use without adverselyaffecting the bias and precision of the test method. Type IIwater was specified at the time of round-robin testing of thistest method.8.3 Barium Solution, Stock (1.0 mL = 10
28、00 g barium)Dissolve 1.779 g of barium chloride (BaCl22H2O) in 50 mL ofconcentrated hydrochloric acid (HCl) (sp gr 1.19) and about700 mL of water. Dilute to 1 L with water. A purchased stocksolution of appropriate purity is also acceptable.8.4 Barium Solution, Intermediate (1.0 mL = 10 gbarium)Dilut
29、e 10.0 mL of barium solution, stock (8.3) and 1mL of HNO3(sp gr 1.42) to 1 L with water.8.5 Barium Solution, Standard (1.0 mL = 0.10 gbarium)Dilute 10.0 mLof barium intermediate solution (8.4)and 1 mL of HNO3(sp gr 1.42) to 1 L with water. This standardis used to prepare working standards at the tim
30、e of the analysis.8.6 Nitric Acid (sp gr 1.42)Concentrated nitric acid(HNO3).NOTE 4If the reagent blank concentration is greater than the methoddetection limit, distill the HNO3or use a spectrograde acid.8.7 Argon, standard, welders grade, commercially available.Nitrogen and hydrogen may also be use
31、d, if recommended bythe instrument manufacturer.9. Standardization9.1 Initially, set the instrument in accordance with themanufacturers specifications. Follow the general instructionsas provided in Practice D 3919.10. Procedure10.1 Clean all glassware to be used for preparation ofstandard solutions
32、or in the digestion step, or both, by rinsingfirst with HNO3(1 + 1) and then with water. Alternatively,soaking the glassware overnight in (1 + 1) HNO3is useful forlow levels.10.2 Measure 100 mL of each standard and well-mixedsample into a 125-mL beaker or flask.3Standards Method for the Examination
33、of Water and Wastewater, 15th Edition,American Public Health Assn., 1015 15th St., NW, Washington, DC 20005.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, s
34、ee Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.D 4382 02 (2007)e1210.3 For total recoverable barium, add 5 mL HNO3(sp gr1.42) to each standard and sample an
35、d proceed as directed in10.4-10.6. If only dissolved barium is to be determined, take analiquot of sample that has been filtered through a 0.45-mmembrane filter and proceed to 10.6.10.4 Heat the samples at approximately 95C on a steambath or hotplate in a well-ventilated fume hood until thevolume ha
36、s been reduced to 15 to 20 mL, making certain thatthe samples do not boil.NOTE 5When analyzing samples of brines or samples containingappreciable amounts of suspended matter or dissolved solids, the amountof reduction in volume is left to the discretion of the analyst.10.5 Cool and filter the sample
37、 through a suitable filter suchas fine-textured, acid washed, ashless paper, into a 100-mLvolumetric flask. Wash the filter paper two or three times withwater and bring to volume.NOTE 6If suspended material is not present, this filtration may beomitted; however, sample must still be diluted to 100 m
38、L.10.6 Inject a measured aliquot of sample into the furnacedevice following the directions as provided by the particularinstrument manufacturer. Refer to Practice D 3919. Matrixmodification using ammonium nitrate (NH4NO3) should beemployed if levels of chloride and sulfate are sufficiently highto ca
39、use interference.11. Calculation11.1 Determine the concentration of barium in each sampleby referring to the Sample Analysis Procedure section ofPractice D 3919.12. Precision and Bias512.1 Based on data from six participating laboratories, theoverall precision of the test method and recoveries from
40、aseries of standards containing known amounts of barium, are asgiven in Table 1.12.2 Because of the large number of metals analyzed in thisstudy, the requirements for replicate tests have been waived;therefore, single-operator precision is not available.12.3 Each participating laboratory evaluated t
41、his testmethod in reagent water. Individual laboratories selected onewater of choice as an additional matrix of interest in which totest recovery. Listed among those choices were: waste treat-ment plant effluent, lake water, tap water, and well water.12.4 These data may not apply to waters of other
42、matrices.12.5 Precision and bias for this test method conforms toPractice D 2777 77, which was in place at the time ofcollaborative testing. Under the allowances made in 1.4 ofPractice D 2777 06, these precision and bias data meetexisting requirements for interlaboratory studies of CommitteeD19 test
43、 methods.13. Quality Control13.1 In order to be certain that analytical values obtainedusing this test method are valid and accurate within theconfidence limits of the test, the following QC procedures mustbe followed when analyzing Barium by graphite furnace AA.13.2 Calibration and Calibration Veri
44、fication:13.2.1 Analyze at least three working standards containingconcentrations of barium that bracket the expected sampleconcentration prior to analysis of samples to calibrate theinstrument.13.2.2 Verify instrument calibration after standardization byanalyzing a standard at the concentration of
45、one of thecalibration standards. The absorbance shall fall within 4 % ofthe absorbance from the calibration. Alternately, the concen-tration of a mid-range standard should fall within 610 % of theknown concentration.13.2.3 If calibration cannot be verified, recalibrate theinstrument.13.3 Initial Dem
46、onstration of Laboratory Capability:13.3.1 If a laboratory has not performed the test before, or ifthere has been a major change in the measurement system, forexample, new analyst, new instrument, etc., a precision andbias study must be performed to demonstrate laboratorycapability.13.3.2 Analyze se
47、ven replicates of a standard solutionprepared from an Independent Reference Material containing100 g/L of barium. The matrix and chemistry of the solutionshould be equivalent to the solution used in the collaborativestudy. Each replicate must be taken through the completeanalytical test method inclu
48、ding any sample preservation andpretreatment steps. The replicates may be interspersed withsamples.13.3.3 Calculate the mean and standard deviation of theseven values and compare to the acceptable ranges of bias inTable 1 above. This study should be repeated until therecoveries are within the limits
49、 given in Table 1. If a concen-tration other than the recommended concentration is used, referto Test Method D 5847 for information on applying the F testand t test in evaluating the acceptability of the mean andstandard deviation.13.4 Laboratory Control Sample (LCS):13.4.1 To ensure that the test method is in control, analyzea LCS containing a mid-range concentration of barium witheach batch or 10 samples. If large numbers of samples areanalyzed in the batch, analyze the LCS after every 10 samples.The LCS must be taken through all of the steps of the a
