ASTM D4382-2018 Standard Test Method for Barium in Water Atomic Absorption Spectrophotometry Graphite Furnace.pdf

1、Designation: D4382 12D4382 18Standard Test Method forBarium in Water, Atomic Absorption Spectrophotometry,Graphite Furnace1This standard is issued under the fixed designation D4382; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t

2、he year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determination of dissolved and total recoverable barium in most waters and was

3、tewaters.1.2 This test method was evaluated in the range from 33.5 to 132 g/L of barium. The range can be increased or decreased byvarying the volume of sample injected or the instrumental settings. High concentrations may be diluted but preferably should beanalyzed by direct aspiration atomic absor

4、ption spectrophotometry.1.3 This test method has been used successfully with waste treatment plant effluent water, lake water, filtered tap water, and wellwater. It is the responsibility of the analyst to determine the suitability of the test method for other matrices.1.4 The values stated in SI uni

5、ts are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety safety, healt

6、h, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of Interna

7、tional Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D858 Test Methods for Manganese in WaterD1068 Test Methods for Iron in WaterD1129 Terminology Relating to WaterD1193 Specification

8、 for Reagent WaterD1687 Test Methods for Chromium in WaterD1688 Test Methods for Copper in WaterD1886 Test Methods for Nickel in WaterD1976 Test Method for Elements in Water by Inductively-Coupled Argon Plasma Atomic Emission SpectroscopyD2777 Practice for Determination of Precision and Bias of Appl

9、icable Test Methods of Committee D19 on WaterD2972 Test Methods for Arsenic in WaterD3373 Test Method for Vanadium in WaterD3557 Test Methods for Cadmium in WaterD3558 Test Methods for Cobalt in WaterD3559 Test Methods for Lead in WaterD3859 Test Methods for Selenium in WaterD3866 Test Methods for S

10、ilver in WaterD3919 Practice for Measuring Trace Elements in Water by Graphite Furnace Atomic Absorption SpectrophotometryD4691 Practice for Measuring Elements in Water by Flame Atomic Absorption SpectrophotometryD4841 Practice for Estimation of Holding Time for Water Samples Containing Organic and

11、Inorganic Constituents1 This test method is under the jurisdiction ofASTM Committee D19 on Water and is the direct responsibility of Subcommittee D19.05 on Inorganic Constituents in Water.Current edition approved Sept. 1, 2012Feb. 1, 2018. Published September 2012May 2018. Originally approved in 198

12、4. Last previous edition approved in 20022012 asD4382 95 (2007)D4382 12.1. DOI: 10.1520/D4382-12.10.1520/D4382-18.2 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

13、 standards Document Summary page on the ASTM website.This document is not an ASTM 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 acc

14、urately, ASTM recommends that users consult prior editions as appropriate. In all 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 Harbo

15、r Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D5673 Test Method for Elements in Water by Inductively Coupled PlasmaMass SpectrometryD5810 Guide for Spiking into Aqueous SamplesD5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analys

16、is3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this test method, refer to Terminology D1129.3.1 Definitions:3.1.1 For definitions of terms used in this standard, refer to Terminology D1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 total recoverable barium, nan

17、arbitrary analytical a descriptive term relating to the recoverable forms of barium that aredeterminable by the digestion method which is included in this test method.4. Summary of Test Method4.1 Barium is determined by an atomic absorption spectrophotometer used in conjunction with a graphite furna

18、ce. A sample isplaced in a graphite tube, evaporated to dryness, charred (pyrolyzed or ashed), and atomized. The absorption signal producedduring atomization may be recorded and compared with values obtained from standards that have been carried through the sameprocess. This facilitates interpolatio

19、n of the level of barium in the solution being analyzed. Since the graphite furnace uses thesample much more efficiently than flame atomization, the detection of low concentrations in small sample volumes is possible.NOTE 1The same graphite furnace procedure may be applicable to determination of ars

20、enic (see Test Methods D2972), cadmium (see Test MethodsD3557), chromium (see Test Methods D1687), cobalt (see Test Methods D3558), copper (see Test Methods D1688), iron (see Test Methods D1068), lead(see Test Methods D3559), manganese (see Test Methods D858), nickel (see Test Methods D1886), seleni

21、um (see Test Methods D3859), silver (see TestMethods D3866), and vanadium (see Test Method D3373).4.2 Dissolved barium is determined on a sample filtered through a 0.45-m membrane filter. The definition of dissolved bariumis arbitrary since very fine crystals of barium sulfate may pass through the m

22、embrane filter.4.3 Total recoverable barium is determined following acid digestion and filtration. Because chlorides interfere with furnaceprocedures for some metals, the use of hydrochloric acid in any digestion or solubilization step is to be avoided. If suspendedmaterial is not present, this dige

23、stion and filtration may be omitted. The holding time for the samples may be calculated inaccordance with Practice D4841.4.4 ICP-MS or ICP-AES may also be appropriate but at a higher instrument cost. See Test Methods D5673 and D1976.5. Significance and Use5.1 Barium ranks about sixth in order of abu

24、ndance in nature; however, it is normally found in only trace quantities in drinkingwater. Consumption, inhalation, or absorption of 500 to 600 mg is considered fatal to human beings. Lower levels may result indisorders of the heart, blood vessels, and nerves. The drinking water standards set the ma

25、ximum contaminant level for barium as2 mg/L.3 Lower levels may result in disorders of the heart, blood vessels, and nerves. The drinking water standards set themaximum contaminant level for barium as 2 mg/L.6. Interferences6.1 For a complete discussion on general interferences with furnace procedure

26、s, refer to Practice D3919.7. Apparatus7.1 Atomic Absorption Spectrophotometer, for use at 553.6 nm with background correction. A general guide for flame atomicabsorption applications is given in Practice D4691.NOTE 2A wavelength other than 553.6 nm may be used if it has been determined to be suitab

27、le. At high concentration, greater linearity may beobtained by using a less sensitive wavelength.NOTE 3The manufacturers instructions should be followed for all instrumental parameters.7.2 Barium Light SourceBarium hollow-cathode lamp. A single-element lamp is preferred. Multielement lamps containin

28、gcalcium are not recommended.7.3 Graphite Furnace, capable of reaching temperatures sufficient to atomize the element of interest.7.4 Graphite Tubes, compatible with furnace device. To eliminate the formation of carbides, pyrolytically coated graphite tubesare recommended.3 Standards Method for the

29、Examination of Water and Wastewater, 15th Edition, American Public Health Assn., 1015 15th St., NW, Washington, DC 20005.D4382 1827.5 Data Storage and Reduction DevicesComputer and microprocessor controlled devices, or a strip chart recorder, shall beutilized for data collection, storage, reduction,

30、 and problem recognition (drift, incomplete atomization, changes in sensitivity, etc.).7.6 Automatic Sampling accessory should be used, if available.8. Reagents and Materials8.1 Purity of ReagentsReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allr

31、eagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, wheresuch specifications are available. 4 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently highpurity to permit its use without lessenin

32、g the accuracy of the determination.8.2 Purity of WaterUnless otherwise indicated, references to water shall be understood to mean reagent water conforming toSpecification D1193, Type I. Other reagent water types may be used, provided it is first ascertained that the water is of sufficientlyhigh pur

33、ity to permit its use without adversely affecting the bias and precision of the test method. Type II water was specified atthe time of round-robin testing of this test method.8.3 Barium Solution, Stock (1.0 mL = 1000 g barium)Dissolve 1.779 g of barium chloride (BaCl22H2O) in 50 mL ofconcentrated hy

34、drochloric acid (HCl) (sp gr 1.19) and about 700 mL of water. Dilute to 1 L with water. A purchased barium stocksolution of appropriate known purity is also acceptable.8.4 Barium Solution, Intermediate (1.0 mL = 10 g barium)Dilute 10.0 mLof barium solution, stock (8.3) and 1 mLof HNO3(sp gr 1.42) to

35、 1 L with water.8.5 Barium Solution, Standard (1.0 mL = 0.10 g barium)Dilute 10.0 mL of barium intermediate solution (8.4) and 1 mL ofHNO3 (sp gr 1.42) to 1 L with water. This standard is used to prepare working standards at the time of the analysis.8.6 Nitric Acid (sp gr 1.42)Concentrated nitric ac

36、id (HNO3).NOTE 4If the reagent blank concentration is greater than the method detection limit, distill the HNO3 or use a spectrograde acid.8.7 Argon, standard, welders grade, commercially available. Nitrogen and hydrogen may also be used, if recommended by theinstrument manufacturer.8.8 Filter Paper

37、Purchase suitable filter paper.Typically the filter papers have a pore size of 0.45-m membrane. Material suchas fine-textured, acid-washed, ashless paper, or glass fiber paper are acceptable. The user must first ascertain that the filter paperis of sufficient purity to use without adversely affectin

38、g the bias and precision of the test method.9. Standardization9.1 Initially, set the instrument in accordance with the manufacturers specifications. Follow the general instructions as providedin Practice D3919.10. Procedure10.1 Clean all glassware to be used for preparation of standard solutions or

39、in the digestion step, or both, by rinsing first withHNO3 (1 + 1) and then with water. Alternatively, soaking the glassware overnight in (1 + 1) HNO3 is useful for low levels.10.2 Measure 100 mL of each standard and well-mixed sample into a 125-mL beaker or flask.10.3 For total recoverable barium, a

40、dd 5 mL HNO3 (sp gr 1.42) to each standard and sample and proceed as directed in 10.4 10.6. If only dissolved barium is to be determined, take an aliquot of sample that has been filtered through a 0.45-m membranefilter (8.8) and proceed to 10.6.10.4 Heat the samples at approximately 95C (between 65C

41、 and 95C) on a steam bath or hotplate below boiling in awell-ventilated fume hood until the volume has been reduced to 15 to 20 mL, making certain that the samples do not boil.NOTE 5When analyzing samples of brines or samples containing appreciable amounts of suspended matter or dissolved solids, th

42、e amount ofreduction in volume is left to the discretion of the analyst.NOTE 6Many laboratories have found block digestion systems a useful way to digest samples for trace metals analysis. Systems typically consist ofeither a metal or graphite block with wells to hold digestion tubes. The block temp

43、erature controller must be able to maintain uniformity of temperatureacross all positions of the block. The digestion block must be capable of maintaining a temperature between 65C and 95C. For trace metals analysis,the digestion tubes should be constructed of polypropylene and have a volume accurac

44、y of at least 0.5%. 0.5 %. All lots of tubes should come with acertificate of analysis to demonstrate suitability for their intended purpose. Make sure that the reagent volumes maintain the same proportions as in themacro method.10.5 Cool and filter (8.8) the sample through a suitable filter such as

45、 fine-textured, acid washed, ashless paper, into a 100-mLvolumetric flask. Wash the filter paper two or three times with water and bring to volume.4 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not

46、listed bythe American Chemical 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.D4382 183NOTE 7If suspended material is not present, this filtrati

47、on may be omitted; however, sample must still be diluted to 100 mL.10.6 Inject a measured aliquot of sample into the furnace device following the directions as provided by the particularinstrument manufacturer. Refer to Practice D3919. Matrix modification using ammonium nitrate (NH4NO3) should be em

48、ployedif levels of chloride and sulfate are sufficiently high to cause interference.11. Calculation11.1 Determine the concentration of barium in each sample by referring to the Sample Analysis Procedure section of PracticeD3919.12. Precision and Bias512.1 Based on data from six participating laborat

49、ories, the overall precision of the test method and recoveries from a series ofstandards containing known amounts of barium, are as given in Table 1.12.2 Because of the large number of metals analyzed in this study, the requirements for replicate tests have been waived;therefore, single-operator precision is not available.12.3 Each participating laboratory evaluated this test method in reagent water. Individual laboratories selected one water ofchoice as an additional matrix of interest in which to test recovery. Listed among those choices we