ASTM D4382-2012 Standard Test Method for Barium in Water Atomic Absorption Spectrophotometry Graphite Furnace《用石墨炉原子吸收分光光度法对水中钡的标准试验方法》.pdf

《ASTM D4382-2012 Standard Test Method for Barium in Water Atomic Absorption Spectrophotometry Graphite Furnace《用石墨炉原子吸收分光光度法对水中钡的标准试验方法》.pdf》由会员分享，可在线阅读，更多相关《ASTM D4382-2012 Standard Test Method for Barium in Water Atomic Absorption Spectrophotometry Graphite Furnace《用石墨炉原子吸收分光光度法对水中钡的标准试验方法》.pdf（6页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: D4382 02 (Reapproved 2007)1D4382 12Standard 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

2、case of revision, the 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 NOTESection 12.5 was updated editorially in September 2007.1. Scope Scope*1.1 This test method cov

3、ers the determination of dissolved and total recoverable barium in most waters and wastewaters.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 concentrat

4、ions may be diluted but preferably should beanalyzed by direct aspiration atomic absorption 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

5、 the suitability of the test method for other matrices.1.4 The values stated in SI units 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 re

6、sponsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D858 Test Methods for Manganese in WaterD1068 Test Methods for Iron in WaterD1129 Terminology

7、 Relating to WaterD1193 Specification for Reagent WaterD1687 Test Methods for Chromium in WaterD1688 Test Methods for Copper in WaterD1886 Test Methods for Nickel in WaterD2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on WaterD2972 Test Methods for

8、 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 Silver in WaterD3919 Practice for Measuring Trace Elements in Water

9、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 Inorganic ConstituentsD5810 Guide for Spiking into Aqueous SamplesD

10、5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis1 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 Aug. 1,

11、2007Sept. 1, 2012. Published September 2007 September 2012. Originally approved in 1984. Last previous edition approved in 2002as D4382 95.D4382 95(2007)E01. DOI: 10.1520/D4382-02R07E01.10.1520/D4382-12.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Serv

12、ice 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 standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previou

13、s version. Becauseit may not be technically possible to adequately depict all changes accurately, 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 Change

14、s section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this test method, refer to Terminology D1129.3.2 Definitions of Terms Sp

15、ecific to This Standard:3.2.1 total recoverable bariumbarium, nan arbitrary analytical 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 spectro

16、photometer used in conjunction with a graphite furnace. 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 th

17、rough the sameprocess. This facilitates interpolation 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

18、 procedure may be applicable to determination of arsenic (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 Me

19、thods D858), nickel (see Test Methods D1886), selenium (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 fi

20、ne crystals of barium sulfate may pass through the membrane 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 avo

21、ided. If suspendedmaterial is not present, this digestion and filtration may be omitted. The holding time for the samples may be calculated inaccordance with Practice D4841.5. Significance and Use5.1 Barium ranks about sixth in order of abundance in nature; however, it is normally found in only trac

22、e 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 maximum contaminant level for barium as2 mg/L3 Lower levels ma

23、y result in disorders of the heart, blood vessels, and nerves. The drinking water standards set themaximum contaminant level for barium as 2 mg barium/L.mg/L.6. Interferences6.1 For a complete discussion on general interferences with furnace procedures, refer to Practice D3919.7. Apparatus7.1 Atomic

24、 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 suitable. At high concentration, greater linearity may

25、 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 containingcalcium are not recommended.7.3 Graphite Furnac

26、e, 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.7.5 Data Storage and Reduction DevicesComputer and microprocessor controlle

27、d devices, or a strip chart recorder, shall beutilized for data collection, storage, reduction, 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 g

28、rade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, where3 Standards Method for the Examination of Water and Wastewater, 15th Edition, Amer

29、ican Public Health Assn., 1015 15th St., NW, Washington, DC 20005.D4382 122such 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 lessening the accuracy of the determination.8.2 Purity o

30、f 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 purity to permit its use without adversely affectin

31、g 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 hydrochloric acid (HCl) (sp gr 1.19) and about 700

32、 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 1 L with water.8.5 Barium Solution, Standard (1

33、.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 acid (HNO3).NOTE 4If the reagent blank concentrati

34、on 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.9. Standardization9.1 Initially, set the instrument in accordanc

35、e 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 in the digestion step, or both, by rinsing first withHNO3 (1 + 1) and then with water. Alternatively, soakin

36、g 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, add 5 mL HNO3 (sp gr 1.42) to each standard and sample and proceed as directed in10.4-10.6. If only dissolved

37、 barium is to be determined, take an aliquot 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 steam bath or hotplate in a well-ventilated fume hood until the volume hasbeen reduced to 15 to 20 mL, making certain that

38、 the samples do not boil.NOTE 5When analyzing samples of brines or samples containing appreciable amounts of suspended matter or dissolved solids, the amount ofreduction in volume is left to the discretion of the analyst.NOTE 6Many laboratories have found block digestion systems a useful way to dige

39、st 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

40、should 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.10.5 Cool and filter the sample through a suitable filter such as fine-textured, acid washed, ashless

41、paper, into a 100-mLvolumetric flask. Wash the filter paper two or three times with water and bring to volume.NOTE 7If suspended material is not present, this filtration may be omitted; however, sample must still be diluted to 100 mL.10.6 Inject a measured aliquot of sample into the furnace device f

42、ollowing the directions as provided by the particularinstrument manufacturer. Refer to Practice D3919. Matrix modification using ammonium nitrate (NH4NO3) should be employedif levels of chloride and sulfate are sufficiently high to cause interference.11. Calculation11.1 Determine the concentration o

43、f 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 laboratories, the overall precision of the test method and recoveries from a series ofstandards containing known amounts of barium, are as g

44、iven in Table 1.4 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed bythe American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the Unite

45、d States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.5 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D19-1104.D4382 12312.2 Because of the large number of metals analyzed in th

46、is 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 te

47、st recovery. Listed among those choices were: waste treatment plant effluent,lake water, tap water, and well water.12.4 These data may not apply to waters of other matrices.12.5 Precision and bias for this test method conforms to Practice D2777 77, which was in place at the time of collaborativetest

48、ing. Under the allowances made in 1.4 of Practice D2777 06, 08, these precision and bias data meet existing requirementsfor interlaboratory studies of Committee D19 test methods.13. Quality Control13.1 In order to be certain that analytical values obtained using this test method are valid and accura

49、te within the confidencelimits of the test, the following QC procedures must be followed when analyzing Barium by graphite furnace AA.13.2 Calibration and Calibration Verification:13.2.1 Analyze at least three working standards containing concentrations of barium that bracket the expected sampleconcentration prior to analysis of samples to calibrate the instrument.13.2.2 Verify instrument calibration after standardization by analyzing a standard at the concentration of one of the calibrationstandards. The absorbance shall fall within 4 % of