ASTM D3223-2017 Standard Test Method for Total Mercury in Water《水中总汞含量的标准试验方法》.pdf

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1、Designation: D3223 12D3223 17Standard Test Method forTotal Mercury in Water1This standard is issued under the fixed designation D3223; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parenthes

2、es 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 U.S. Department of Defense.1. Scope*1.1 This test method2 covers the determination of total mercury in wate

3、r in the range from 0.5 to 10.0 g Hg/L (1).3 The testmethod is applicable to fresh waters, saline waters, and some industrial and sewage effluents. It is the users responsibility to ensurethe validity of this test method for waters of untested matrices.1.1.1 The analyst should recognize that the pre

4、cision and bias of this standard may be affected by the other constituents in allwaters, as tap, industrial, river, and wastewaters. The cold vapor atomic absorption measurement portion of this method isapplicable to the analysis of materials other than water (sediments, biological materials, tissue

5、s, etc.) if, and only if, an initialprocedure for digesting and oxidizing the sample is carried out, ensuring that the mercury in the sample is converted to the mercuricion, and is dissolved in aqueous media (2, 3).1.2 Both organic and inorganic mercury compounds may be analyzed by this procedure if

6、 they are first converted to mercuricions. Using potassium persulfate and potassium permanganate as oxidants, and a digestion temperature of 95C, approximately100 % recovery of organomercury compounds can be obtained (2, 4).1.3 The range of the test method may be changed by instrument or recorder ex

7、pansion or both, and by using a larger volumeof sample.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 A method for the disposal of mercury-containing wastes is also presented (Appendix X1) (5).1.6 WarningMercury has b

8、een designated by many regulatory agencies as a hazardous material that can cause seriousmedical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Caution shouldbe taken when handling mercury and mercury containing products. See the applicable

9、 product Safety Data Sheet (SDS) foradditional information. Users should be aware that selling mercury and/or mercury containing products into your state or countrymay be prohibited by law.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It i

10、s the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. For specific hazard statements, see 7.81.6 and 10.8.27.8.1.8 This international standard was developed in accordance with inter

11、nationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:4D512 Te

12、st Methods for Chloride Ion In WaterD1129 Terminology Relating to WaterD1193 Specification for Reagent Water1 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 S

13、ept. 1, 2012June 1, 2017. Published September 2012June 2017. Originally approved in 1979. Last previous edition approved in 2002 asD3223 02 (2007)D32231. 12. DOI: 10.1520/D3223-12. 10.1520/D3223-17.2 Adapted from research investigations by the U. S. Environmental ProtectionAgencysAnalytical Quality

14、Control Laboratory, Cincinnati, OH, and Region IVSurveillanceand Analysis Division, Chemical Services Branch, Athens, GA.3 The boldface numbers in parentheses refer to the references at the end of this test method.4 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Cu

15、stomer Service 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

16、the previous 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 Summar

17、y of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D1245 Practice for Examination of Water-Formed Deposits by Chemical MicroscopyD1252 Test Methods for Chemical Oxygen Demand (Dichr

18、omate Oxygen Demand) of WaterD1426 Test Methods for Ammonia Nitrogen In WaterD2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on WaterD3370 Practices for Sampling Water from Closed ConduitsD4691 Practice for Measuring Elements in Water by Flame Atomi

19、c Absorption SpectrophotometryD4841 Practice for Estimation of Holding Time for Water Samples Containing Organic and Inorganic ConstituentsD5810 Guide for Spiking into Aqueous SamplesD5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis3. Terminology3

20、.1 Definitions:3.1.1 For definitions of terms used in this standard, refer to Terminology D1129.3.2 DefinitionsDefinitions of Terms Specific to This Standard:For3.2.1 continuing calibration blank, n a solution containing no analytes (of interest) which is used to verify blank response andfreedom fro

21、m carryover.3.2.2 continuing calibration verification, na solution (or set of solutions) of known concentration used to verify freedom fromexcessive instrumental drift; the concentration is to cover the range of calibration curve.definitions3.2.3 total recoverable mercury, na descriptive term relati

22、ng to the metal forms of mercury recovered in the acid digestionprocedure specified in this test standard. of terms used in this test method, refer to Terminology D1129.4. Summary of Test Method4.1 The test method consists of a wet chemical oxidation which converts all mercury to the mercuric ion; r

23、eduction of mercuricions to metallic mercury, followed by a cold vapor atomic absorption analysis (1, 2). A general guide for flame and vaporgeneration atomic absorption applications is given in Practice D4691.4.2 Cold vapor atomic absorption analysis is a physical method based on the absorption of

24、ultraviolet radiation at a wavelengthof 253.7 nm by mercury vapor. The mercury is reduced to the elemental state and aerated from solution in either a closedrecirculating system or an open one-pass system. The mercury vapor passes through a cell positioned in the light path of an atomicabsorption sp

25、ectrophotometer. Absorbance is measured as a function of mercury concentration.5. Significance and Use5.1 The presence of mercury in industrial discharge, domestic discharge, and potable water is of concern to the public becauseof its toxicity. Regulations and standards have been established that re

26、quire the monitoring of mercury in water. This test methodprovides an analytical procedure to measure total mercury in water.6. Interference6.1 Possible interference from sulfide is eliminated by the addition of potassium permanganate. Concentrations as high as 20mg/L of sulfide as sodium sulfide do

27、 not interfere with the recovery of added inorganic mercury from distilled water (2).6.2 Copper has also been reported to interfere; however, copper concentrations as high as 10 mg/L have no effect on therecovery of mercury from spiked samples (2).6.3 Seawaters, brines, and industrial effluents high

28、 in chlorides require additional permanganate (as much as 25 mL). Duringthe oxidation step chlorides are converted to free chlorine which will also absorb radiation at 253.7 nm. Care must be taken toassure that free chlorine is absent before mercury is reduced and swept into the cell. This may be ac

29、complished by using an excessof hydroxylamine sulfate reagent (25 mL). The dead air space in the reaction flask must also be purged before the addition ofstannous sulfate. Both inorganic and organic mercury spikes have been quantitatively recovered from sea water using thistechnique (2).6.4 Volatile

30、 organic materials that could interfere will be removed with sample digestion as described in 11.2 through 11.4.7. ApparatusNOTE 1Take care to avoid contamination of the apparatus with mercury. Soak allAn effective way to clean all glassware is to soak all glass apparatus,pipets, beakers, aeration t

31、ubes, and reaction flasks in nitric acid (HNO3) (1 + 1), and rinse with mercury-free water or reagent before use.7.1 The schematic arrangement of the closed recirculating system is shown in Fig. 1 and the schematic arrangement of the openone-pass system is shown in Fig. 2.7.2 Atomic Absorption Spect

32、rophotometerAcommercial atomic absorption instrument is suitable if it has an open-burner headarea in which to mount an absorption cell, and if it provides the sensitivity and stability for the analyses.Also instruments designedspecifically for the measurement of mercury using the cold vapor techniq

33、ue in the working range specified may be used. Directreading instruments are also acceptable.D3223 1727.2.1 Mercury Hollow Cathode Lamp.7.2.2 Simultaneous Background CorrectionBackground correction may be necessary to compensate for molecular absorptionthat can occur at this mercury wavelength. It i

34、s the analysts responsibility to determine the applicable use.7.3 RecorderAny multirange variable speed recorder that is compatible with the ultraviolet (UV) detection system is suitable.7.4 Absorption CellThe cell (Fig. 3) is constructed from glass 25.4-mm outside diameter by 114 mm (Note 2). The e

35、nds areground perpendicular to the longitudinal axis and quartz windows (25.4-mm diameter by 1.6 mm thickness) are cemented in place.Gas inlet and outlet ports (6.4-mm diameter) are attached approximately 12 mm from each end. The cell is strapped to a supportand aligned in the light beam to give max

36、imum transmittance.NOTE 2An all-glass absorption cell, 18 mm in outside diameter by 200 mm, with inlet 12 mm from the end, 18-mm outside diameter outlet in thecenter, and with quartz windows has been found suitable. Methyl methacrylate tubing may also be used.7.5 Air PumpA peristaltic pump, with ele

37、ctronic speed control, capable of delivering 1 L of air per minute may be used.Regulated compressed air can be used in the open one-pass system.7.6 Flowmeter, capable of measuring an air flow of 1 L/min.7.7 Aeration TubingAstraight glass frit having a coarse porosity is used in the reaction flask. C

38、lear flexible vinyl plastic tubingis used for passage of the mercury vapor from the reaction flask to the absorption cell.7.8 LampA small reading lamp containing a 60-W bulb is used to prevent condensation of moisture inside the cell. The lampshall be positioned to shine on the absorption cell maint

39、aining the air temperature in the cell about 10C above ambient.Alternatively, a drying tube, 150 by 18 mm in diameter, containing 20 g of magnesium perchlorate, may be placed in the line toprevent moisture in the absorption cell. (WarningIf the presence of organic vapors is expected, the purity of t

40、he drying agentshould be determined to establish the absence of traces of free perchloric acid in the salt. This is to prevent the formation ofperchloric esters, some of which are known to be violently explosive compounds.)7.9 Reaction FlaskA 250- to 300-mL glass container fitted with a rubber stopp

41、er may be used.AReaction flask GHollow cathode mercury lampB60-W light bulb HAtomic absorption detectorCRotameter, 1 L of air per minute J Gas washing bottle containing0.25 % iodine in a 3 % potassium io-dide solutionD Absorption cell with quartz windows KRecorder, any compatible modelE Air pump, 1

42、L of air per minuteFGlass tube with fritted endFIG. 1 Schematic Arrangement of Equipment for Mercury Measurement by Cold Vapor Atomic Absorption Technique Closed Recircu-lating SystemD3223 1738. Reagents8.1 Purity of ReagentsReagent grade chemicals shall be used in all tests. Unless otherwise indica

43、ted, it is intended that allreagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society.5 Othergrades may be used, provided it is first ascertained that the reagent is of sufficiently high purity to permit its use without lesseningthe accurac

44、y of the determination.5 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 th

45、e United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.AReaction flask GHollow cathode mercury lampB60-W light bulb HAtomic absorption detectorCRotameter, 1 L of air per minute JVent to hoodD Absorption cell with quartz windows K Recorder, any c

46、ompatible modelE Compressed air, 1 L of air per min-uteL To vacuum through gas washingbottle containing 0.25 % iodine in a 3 %potassium iodide solutionFGlass tube with fritted endFIG. 2 Schematic Arrangement of Equipment for Mercury Measurement by Cold Vapor Atomic Absorption Technique Open One-Pass

47、SystemNOTE 1The length and outside diameter of the cell are not critical. The body of the cell may be of any tubular material but the end windows mustbe of quartz because of the need for UV transparency. The length and diameter of the inlet and outlet tubes are not important, but their position may

48、bea factor in eliminating recorder noise. There is some evidence that displacement of the air inlet tube away from the end of the cell results in smootherreadings. A mild pressure in the cell can be tolerated, but too much pressure may cause the glued-on end windows to pop off. Cells of this type ma

49、y bepurchased from various supply houses.FIG. 3 Cell for Mercury Measurement by Cold-Vapor TechniqueD3223 1748.2 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 purity 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 thi