ASTM D3373-2012 Standard Test Method for Vanadium in Water《水中钒的标准试验方法》.pdf

1、Designation: D3373 03 (Reapproved 2007)1D3373 12Standard Test Method forVanadium in Water1This standard is issued under the fixed designation D3373; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numbe

2、r in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1 NOTESections 7.5 and 13.5 were updated editorially in September 20071

3、 Scope Scope*1.1 This test method covers the determination of dissolved and total recoverable vanadium in most waters and wastewater bygraphite furnace atomic absorption spectrophotometry.1.2 The optimum range of this test method is 10 to 200 g/L of vanadium based on a 20-L sample size. Concentrati

4、ons higherthan 200 g/L may be determined by proper dilution of sample.Adetection level as low as 4 g/L of vanadium has been reported.1.3 This test method has been used successfully with reagent water, lake water, tap water, river water, condensate from amedium Btu coal gasification process, and well

5、 water. It is the users responsibility to ensure the validity of this test method forwaters of untested 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 safe

6、ty concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability or regulatorylimitations prior to use.1.6 Former Test Method A (Catalytic) was discontinued. Refer to Appendix X1 fo

7、r historical information.2. Referenced Documents2.1 ASTM Standards:2D1066 Practice for Sampling SteamD1129 Terminology Relating to WaterD1192 Guide for Equipment for Sampling Water and Steam in Closed Conduits (Withdrawn 2003)3D1193 Specification for Reagent WaterD2777 Practice for Determination of

8、Precision and Bias of Applicable Test Methods of Committee D19 on WaterD3370 Practices for Sampling Water from Closed ConduitsD3919 Practice for Measuring Trace Elements in Water by Graphite Furnace Atomic Absorption SpectrophotometryD4841 Practice for Estimation of Holding Time for Water Samples Co

9、ntaining Organic and Inorganic ConstituentsD5810 Guide for Spiking into Aqueous SamplesD5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis3. Terminology3.1 Definitions: For definitions of terms used in this test method refer to Terminology D1129.3.2

10、 Definitions of Terms Specific to This Standard:3.2.1 total recoverable vanadiumvanadium, ndissolved vanadium plus that solubilized by acid digestion of particulates andorganics in the sample.4. Summary of Test Method4.1 Vanadium is determined by an atomic absorption spectrophotometer utilizing a gr

11、aphite furnace for sample atomization.1 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, 2007Sept. 1, 2012. Published September 2007 September 2012. Ori

12、ginally approved in 1975. Last previous edition approved in 20032007as D3373 03.D3373 03(2007)E01. DOI: 10.1520/D3373-03R07E01.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information,

13、 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 previous version. Becauseit may not be technically possible to adequately depict al

14、l 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 Changes section appears at the end of this standardCopyright ASTM International, 1

15、00 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.2 A sample volume of several microlitres, depending upon the concentration of the analyte, is transferred to a graphite tubehoused within an electrical furnace and the system is heated in an inert or reducing atmosp

16、here. The sample is evaporated todryness, charred (pyrolyzed or ashed) and atomized.4.3 Ground state atoms, produced in atomization, absorb the light of their spectrum emanating from a source and passingthrough the sample vapor. The amount of light absorbed is proportional to the concentration of th

17、e analyte in the sample.4.4 Since the graphite furnace uses the sample much more efficiently than does flame atomization, the detection of lowconcentrations of the elements of interest in small volumes is possible.4.5 Finally, the absorption signal produced during atomization is recorded and compare

18、d to those of standards, taken throughthe same process, by means of an analytical curve.4.6 A general guide for graphite furnace applications is given in Practice D3919.4.7 Dissolved vanadium is determined after filtration and addition of HNO3 to a pH of 2.4.8 Total recoverable vanadium is determine

19、d following acid digestion and filtration.5. Significance and Use5.1 Vanadium can be found in waste that result from chemical cleaning of components in which the metal is alloyed.5.2 National Pollutant Discharge Elimination Systems permits or other standards, or both, require monitoring pollutants i

20、n wastedischarged onto the water shed of, or into, navigable waters, and those disposed of in such a manner that eventual contaminationof underground water could result.5.3 This test method affords an accurate and sensitive means of determining compliance or noncompliance, or both, with thosepermits

21、6. Interferences6.1 For a complete discussion on general interferences with furnace procedures, the analyst is referred to Practice D3919.7. Apparatus7.1 Atomic Absorption Spectrophotometer , for use at 318.4 nm with background correction.NOTE 1The manufacturers instructions should be followed for

22、all instrumental parameters.7.2 Vanadium Hollow Cathode Lamp.7.3 Graphite Furnace capable of reaching temperature sufficient to atomize the element of interest.7.4 Graphite Tubes, pyrolytically coated, compatible with furnace device are recommended.7.5 Pipettes, microlitre with disposable tips, rang

23、ing in size from 1 to 100 L.7.6 Strip Chart RecorderA recorder is strongly recommended. The tracings can be used as permanent records and are ofdiagnostic value in the identification and analysis of instrument problems (such as drift, incomplete atomization, change insensitivity, etc.). A fast respo

24、nse recorder (0.2 s or less for full-scale deflection) is recommended to ensure accuracy. Electronicpeak-measuring devices have also been found useful.7.7 Automatic Sampling Accessory is recommended, if available.8. Reagents and Materials8.1 Purity of ReagentsReagent grade chemicals shall be used in

25、 all tests. Unless otherwise indicated, it is intended that allreagents shall conform to the specifications of Committee on Analytical Reagents of the American Chemical Society, where suchspecifications are available.3 Other grades may be used, provided it is first ascertained that the reagent is of

26、 sufficiently high purityto permit its use without lessening 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 f

27、irst ascertained that the water is of sufficientlyhigh purity to permit its use without adversely affecting the precision and bias of the test method.8.3 Nitric Acid (sp gr 1.42)Concentrated nitric acid (HNO3).8.4 Vanadium Solution, Stock (1.0 mL = 100 g vanadium). Dissolve 0.2296 g of ammonium meta

28、vanadate (NH4VO3) in waterand dilute to 1000 mL. A purchased vanadium stock solution of appropriate known purity is also acceptable.3 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed bythe Am

29、erican 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.D3373 1228.5 Vanadium Solution, Intermediate (1.0 mL = 1.0 g vanadium) Dilute 5 m

30、L of vanadium stock solution to 500 mL withwater.8.6 Vanadium Solution, Standard (1.0 mL = 0.100 g vanadium)Dilute 10.0 mLof vanadium intermediate solution to 100 mLwith water.8.7 Nitrogen Gasstandard, welders grade, commercially available.NOTE 2It is probable that argon or some other inert gas can

31、be used in place of nitrogen. It is the analysts responsibility to verify suitability.9. Sampling9.1 Collect the sample in accordance with PracticePractices D1066, Specification D1192, and Practices D3370, as applicable.The holding time for the sample may be calculated in accordance with Practice D4

32、841.9.2 Preserve samples with nitric acid (HNO3, sp gr 1.42) to a pH of 2 or less immediately at the time of collection, normallyabout 2 mL/L. If only dissolved vanadium is to be determined, filter the sample through a 0.45-m (No. 325) membrane filterbefore acidification.NOTE 3Alternatively, the pH

33、may be adjusted in the laboratory if the sample is returned within 14 days. This could reduce hazards of working withacids in the field when appropriate.10. Standardization10.1 Initially, set the instrument in accordance with the manufacturers specifications. Follow the general instructions asprovid

34、ed in Practice D3919.11. Procedure11.1 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, soaking the glassware overnight in HNO3 (1 + 1) is useful for low levels.11.2 Measure 1

35、00.0 mLof each standard and well-mixed sample into a 125-mLbeaker or flask. For total recoverable vanadium,add 5 mL of HNO3 (sp gr 1.42) to each sample and proceed as directed in 11.4 through 11.6.11.3 If only dissolved vanadium is to be determined, proceed to 11.6.11.4 Heat the samples at 95C on a

36、steam bath or hotplate in a well-ventilated fume hood until the volume has been reducedto 15 to 20 mL making certain that the samples do not boil.NOTE 4When analyzing samples of brines or samples containing appreciable amounts of suspended matter or dissolved solids, the amount ofreduction in volume

37、 is left to the discretion of the analyst.NOTE 5Many 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 temperature controller must be abl

38、e to maintain uniformity of temperatureacross all positions of the block. For trace metals analysis, the digestion tubes 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 thei

39、r intended purpose.11.5 Cool and filter the sample through a suitable filter (such as fine-textured, acid washed, ashless paper) into a 100-mLvolumetric flask. Wash the filter paper 2 or 3 times with water and bring to volume. See Note 46. The acid concentration at thispoint should be 5 % HNO3.NOTE

40、6If suspended material is not present, this filtration may be omitted, however, digested sample must still be diluted to 100 mL.11.6 Inject a measured aliquot of sample into the furnace device following the directions as provided by the particularinstrument manufacturer. Refer to Practice D3919.12.

41、Calculation12.1 Determine the concentration of vanadium in each sample in accordance with the Samples Analysis Procedure Section ofPractice D3919.13. Precision and Bias413.1 Based on data from twelve participating laboratories, the overall precision of this test method and recoveries from a seriesof

42、 standards containing known amounts of vanadium, were as given in Table 1.13.2 Because of the large number of metals analyzed in this study the requirement for replicate tests have been waived;therefore, single-operator precision is not available.13.3 Each participating laboratory evaluated this tes

43、t 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 were: lake water, tap water, riverwater, well water, and condensate from a medium Btu coal gasification process.4 Supporting data h

44、ave been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D19-1114.D3373 12313.4 These data may not apply to waters of other matrices.13.5 This section on precision and bias conforms to Practice D2777 77 which was in place at the time of collaborative tes

45、ting.Under the allowances made in 1.4 of D2777 06, 08, these precision and bias data do meet existing requirements ofinterlaboratory studies of Committee D19 test methods.14. Quality Control14.1 In order to be certain that analytical values obtained using these test methods are valid and accurate wi

46、thin the confidencelimits of the test, the following QC procedures must be followed when analyzing vanadium.14.2 Calibration and Calibration Verification14.2.1 Analyze at least three working standards containing concentrations of vanadium that bracket the expected sampleconcentration, prior to analy

47、sis of samples, to calibrate the instrument. The calibration correlation coefficient shall be equal to orgreater than 0.990. In addition to the initial calibration blank, a calibration blank shall be analyzed at the end of the batch run toensure contamination was not a problem during the batch analy

48、sis.14.2.2 Verify instrument calibration after standardization by analyzing a standard at the concentration of one of the calibrationstandards. The concentration of a mid-range standard should fall within 615% of the known concentration.14.2.3 If calibration cannot be verified, recalibrate the instr

49、ument.14.2.4 It is recommended to analyze a continuing calibration blank (CCB) and continuing calibration verification (CCV) at a10% frequency.14.3 Initial Demonstration of Laboratory Capability14.3.1 If a laboratory has not performed the test before, or if there has been a major change in the measurement system, forexample, new analyst, new instrument, and so forth, a precision and bias study must be performed to demonstrate laboratorycapability.14.3.2 Analyze seven replicates of a standard solution prepared from an Independent Referenc