1、Designation: D4327 11D4327 17Standard Test Method forAnions in Water by Suppressed Ion Chromatography1This standard is issued under the fixed designation D4327; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis
2、ion. 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 method2,3 covers the sequential determination of fluoride, chloride, nitrite, ortho-phosphate, bromide, nitrate, ands
3、ulfate ions in water by suppressed ion chromatography.NOTE 1Order of elution is dependent upon the column used; see Fig. 1.1.2 This test method is applicable to drinking and wastewaters. The ranges tested for this test method for each anion were asfollows (measured in mg/L):Fluoride 0.26 to 8.49Chlo
4、ride 0.78 to 26.0Nitrite-N 0.36 to 12.0Bromide 0.63 to 21.0Nitrate-N 0.42 to 14.0o-Phosphate 0.69 to 23.1Sulfate 2.85 to 95.01.3 It is the users responsibility to ensure the validity of this test method for other matrices.1.4 Concentrations as low as 0.01 mg/Lwere determined depending upon the anion
5、s to be quantified, in single laboratory work.Utilizing a 50-Lsample volume loop and a sensitivity of 33000 S/cm full scale, the approximate detection limits shown in Table1 can be achieved. Lower detection limits have been observed with newer instrumentation, column technology and eluents. Theanaly
6、st must assure optimum instrument performance to maintain a stable baseline at more sensitive conductivity full-scalesettings.1.5 The upper limit of this test method is dependent upon total anion concentration and may be determined experimentally asdescribed in Annex A1. These limits may be extended
7、 by appropriate dilution or by use of a smaller injection volume.1.6 Using alternate separator column and eluents may permit additional anions such as acetate, formate, or citrate to bedetermined. This is not the subject of this test method.1.7 This test method update approves the use of Electrolyti
8、callyelectrolytically generated eluent, electrolytically regeneratedeluent, electrolytic suppression (not autozeroing)autozeroing), and electrolytic trap columns also known as Reagent Free IonChromatography. reagent-free ion chromatography. This approval is based on acceptance by the USU.S. EPA as r
9、eferenced inAppendix X2.1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.9 This standard does not purport to address all of the safety problems,concerns, if any, associated with its use. It is theresponsibility of the use
10、r of this standard to establish appropriate safety safety, health, and healthenvironmental practices anddetermine the applicability of regulatory limitations prior to use.1 This test method is under the jurisdiction ofASTM Committee D19 on Water and is the direct responsibility of Subcommittee D19.0
11、5 on Inorganic Constituents in Water.Current edition approved Jan. 15, 2011Dec. 1, 2017. Published March 2011December 2017. Originally approved in 1984. Last previous edition approved in 20032011as D4327 03.D4327 11. DOI: 10.1520/D4327-11.10.1520/D4327-17.2 TheRefs. following(1-7)3 references may be
12、 consulted for additional information: information.Small, H., Stevens, T. S., and Bauman, W. C., “Novel Ion Exchange Chromatographic Method Using Conductrimetric Detection,” Analytical Chemistry, Vol 47, 1975,p. 1801.Stevens, T. S., Turkelson, V. T., and Alve, W. R., “Determination of Anions in Boil
13、er Blow Down Water with Ion Chromatography,” Analytical Chemistry, Vol 49, 1977,p. 1176.Sawicki, E., Mulik, J. D., and Witgenstein, E., Editors, Ion Chromatographic Analysis of Environmental Pollutants, Ann Arbor Science Publishers, Ann Arbor, MI, 1978.Mulik, J. D., and Sawicki, E., Editors, Ion Chr
14、omatographic Analysis of Environmental Pollutants, Vol/No. 2, Ann Arbor Science Publishers, Ann Arbor, MI, 1979.Weiss, J., Handbook of Ion Chromatography, Dionex Corp., Sunnyvale, CA, 1986.Waters Innovative Methods for Anion Analysis, Waters Chromatography Division of Millipore, Method A 107 and A 1
15、16, 1990.Haddad, P. R., and Jackson, P. E., Ion Chromatography: Principles and Applications, Elsevier Scientific Publishing Co., 1990.3 The boldface numbers in parentheses refer to a list of references at the end of this standard.This document is not an ASTM standard and is intended only to provide
16、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 accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the stan
17、dard 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 Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States11.10 This international standard was developed in acc
18、ordance with internationally 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
19、Standards:4D1066 Practice for Sampling SteamD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on WaterD3370 Practices for Sampling Water from Closed ConduitsD5810 Guide for Spikin
20、g into Aqueous SamplesD5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis3. Terminology3.1 DefinitionsDefinitions: For definitions of terms used in this test method, refer to Terminology D1129.3.1.1 For definitions of terms used in this standard, re
21、fer to Terminology D1129.4 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 standards Document Summary page on the ASTM website.FIG. 1 Chromatogram Showing Separati
22、onUsing the AS4A ColumnTABLE 1 Approximate Single Laboratory Detection Limits inReagent WaterA,BAnalyte Peak No. RetentionTime, min MDLmg/LFluoride 1 1.2 0.01Chloride 2 1.7 0.02Nitrite-N 3 2.0 0.004Bromide 4 2.9 0.01Nitrate-N 5 3.2 0.002o-Phosphate 6 5.4 0.003Sulfate 7 6.9 0.02A Data provided by USU
23、.S. EPA/EMSL Laboratory, Cincinnati, OH.B Column: as specified in 7.1.4.Detector: as specified in 7.1.6.Eluent: as specified in 8.3.Pump rate: 2.0 mL/min.Sample loop: 50 L.D4327 1723.2 Definitions of Terms Specific to This Standard:3.2.1 analytical columns, na combination of one or more guard column
24、s followed by one or more separator columns used toseparate the ions of interest.3.2.1.1 DiscussionIt should be remembered that all of the columns in series contribute to the overall capacity of the analytical column set.3.2.2 suppressor device, continuing calibration blank, na device that is placed
25、 between the analytical columns and thedetector. solution containing no analytes (of interest) which is used to verify blank response and freedom from carryover.3.2.2.1 DiscussionThe purpose of the suppressor is to minimize detector response of ionic constituents in the eluent, which lowers the dete
26、ctorbackground and at the same time enhances detector response to the ions of interest.3.2.3 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 c
27、urve.3.2.4 eluent, nthe ionic mobile phase used to transport the sample through the system.3.2.5 guard column, na column used before the separator column to protect the analytical column from contaminants, suchas particulate matter or irreversibly retained materials.3.2.6 ion chromatography, na form
28、 of liquid chromatography in which ionic constituents are separated by ion exchangefollowed by a suitable detection.3.2.7 resolution, nthe ability of an analytical column to separate constituents under specific test conditions.3.2.8 separator column, nthe ion-exchange or analytical column used to se
29、parate the ions of interest according to the ionretention characteristics prior to their detection.3.2.9 suppressor device, na device that is placed between the analytical columns and the detector.3.2.9.1 DiscussionThe purpose of the suppressor is to minimize detector response of ionic constituents
30、in the eluent, which lowers the detectorbackground and at the same time enhances detector response to the ions of interest.4. Summary of Test Method4.1 An aliquot of sample is injected into an ion chromatograph. The sample is pumped through two columns, a suppressordevice, and into a conductivity de
31、tector. The analytical column and the guard column are packed with anion exchange resin. Ionsare separated based on their affinity for the exchange sites of the resin. The suppressor device contains a fiber- or membrane-basedcation exchanger that is continuously regenerated by either a flow of dilut
32、e sulfuric acid or an electrolytic suppressor which doesnot require sulfuric acid. The suppressor device reduces the background conductivity of the eluent to a low or negligible level byreplacing the cations with the hydrogen ion, thereby converting the anions in the sample to their corresponding ac
33、ids.The separatedanions in their acid form are measured using an electrical-conductivity cell. Anions are identified based on their retention timescompared to known standards. Quantitation is accomplished by measuring the peak height or area and comparing it to a calibrationcurve generated from know
34、n standards.5. Significance and Use5.1 Ion chromatography provides for both qualitative and quantitative determination of seven common anions, F, Cl, NO2,HPO4 2, Br, NO3, and SO42, in the milligram per literlitre range from a single analytical operation requiring only a fewmillilitersmillilitres of
35、sample and taking approximately 10 to 15 min for completion.Additional anions, such as carboxylic acids,can also be quantified.NOTE 2This test method may be used to determine fluoride if its peak is in the water dip by adding one1 mL of eluent (at 100 the concentrationin 8.3) to all 100-mL volumes o
36、f samples and standards to negate the effect of the water dip. (See 6.3, and also see 6.4.) The quantitation of unretainedpeaks should be avoided.Anions such as low molecular weight organic acids (formate, acetate, propionate, etc.) that are conductive coelute with fluorideand would bias fluoride qu
37、antitation in some drinking waters and most wastewaters. The water dip can be further minimized if measures are taken toremove carbonic acid which remain in the eluent after suppression using carbonate based eluents. There is no water dip if hydroxide eluents are used.5.2 Anion combinations such as
38、Cl/Br and NO2/NO3, which may be difficult to distinguish by other analytical methods,are readily separated by ion chromatography.D4327 1736. Interferences6.1 Since chloride and nitrite elute very close together, they are potential interferents for each other. It is advisable not to haveone of these
39、anions present in a ten-fold excess over the other; that is, Cl/NO2 ratios higher than 1:10 or 10:1 if both ions areto be quantitated or refer to newer column technology.6.2 As with other types of chromatography, if one of the sample components is present at very high levels, it may interfere bycaus
40、ing a very large peak on the chromatogram that could mask other peaks present. This type of interference is normallyminimized by dilution of the sample (see Annex A1) and in some instances may be corrected if the concentration of that anionis of interest. However, care should be taken not to dilute
41、the analyte concentration below its detectable limit.6.3 Water from the sample injection will cause a negative peak or dip in the chromatogram when it elutes, because itsconductivity is less than that of the suppressed eluent. This dip usually occurs before Cl. Any peak of interest eluting near thew
42、ater dip must be sufficiently resolved from the dip to be accurately quantified. Some suggested techniques for elimination of thewater dip are described in Appendix X1.6.4 There may be a water dip and the interference of organic acids and due to the presence of carbonate ions in the separatorcolumn,
43、 the user of this test method is urged to use caution when determining fluoride (see Note 2). If the user wishes to be certainof good results and has interfering anions present when determining fluoride, the eluent can be diluted until separation of fluorideand carbonate is accomplished. This will c
44、ause an increase in retention time for anions such as sulfate to elute. Additional stepsto avoid the water dip are mentioned in Appendix X1.7. Apparatus7.1 Ion ChromatographThe ion chromatograph should have the following components assembled, as shown in Fig. 2:57.1.1 Eluent and Regenerant Container
45、s.7.1.2 Eluent Pump, capable of delivering 1 to 3 mL/min of eluent at a pressure of up to 2000 psi.7.1.3 Guard ColumnAnion exchange column, typically of the same anion exchange material used in the separator column.The purpose of this column is to protect the analytical column from particulate matte
46、r and irreversibly retained materials.7.1.4 Analytical ColumnAnion exchange column capable of separating chloride from the injection void volume, as well asresolving the anions chloride through sulfate.NOTE 3Any analytical column may be used. However, the user should be able to achieve the resolutio
47、n and separation as shown in Fig. 1.7.1.5 Suppressor DeviceA suppressor device based upon cation-exchange principles. In this test method a membrane-basedself-regenerating suppressor device was used. An equivalent suppressor device may be used provided that comparable methoddetection limits are achi
48、eved and that adequate baseline stability is attained. An electrolytic suppressor device can be used which5 Available from Dionex Corp., 1228 Titan Way, Sunnyvale, CA94086.An equivalent The Dionex ion chromatograph available from Dionex Corporation, Sunnyvale, CA,or equivalent, may be used. Other ma
49、nufacturers components may provide equivalent data.FIG. 2 Schematic of an Ion ChromatographD4327 174does not require the addition of an acid but is a plug in electrolytic device. The suppressed eluent (water) is simply recirculatedfrom the conductivity cell back to the electrolytic suppressor to back flush the suppressor device. Alternative pumps are alsotypically not required.7.1.6 DetectorA low-volume, flow through, temperature-compensated electrical conductivity cell equipped with a metercapable of reading from 0 to 1000 S/cm on
