1、Designation: D 5542 04 (Reapproved 2009)Standard Test Methods forTrace Anions in High Purity Water by Ion Chromatography1This standard is issued under the fixed designation D 5542; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, th
2、e 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. Scope1.1 These test methods cover the determination of trace(g/L) levels of fluoride, acetate, formate, chloride, pho
3、sphate,and sulfate in high purity water using ion chromatography incombination with sample preconcentration. Other anions, suchas bromide, nitrite, nitrate, sulfite, and iodide can be deter-mined by this method. However, since they are rarely presentin significant concentrations in high purity water
4、, they are notincluded in this test method. Two test methods are presentedand their ranges of application, as determined by a collabora-tive study, are as follows:Range Tested(g/L Added)Limit of DetectionA(Single Operator)(g/L)SectionsTest Method A: 715Chloride 024 0.8Phosphate 039BSulfate 055 1.8Te
5、st Method B: 1623Fluoride 014 0.7Acetate 0414 6.8Formate 0346 5.6ALimit of detection is lowest measurable concentration not reportable as zero at99 % level of confidence as per EPRI study as cited in Sections 15 and 23.BInsufficient data to calculate limit of detection.1.2 It is the users responsibi
6、lity to ensure the validity ofthese test methods for waters of untested matrices.1.3 The common practical range of Test Method A is asfollows: chloride, 1 to 100 g/L, phosphate, 3 to 100 g/L, andsulfate, 2 to 100 g/L.1.4 The common practical range of Test Method B is asfollows: fluoride, 1 to 100 g/
7、L, acetate, 10 to 200 g/L, andformate, 5 to 200 g/L.1.5 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsib
8、ility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1066 Practice for Sampling SteamD 1129 Terminology Relating to WaterD 1192 Guide for Equipment
9、 for Sampling Water andSteam in Closed Conduits3D 1193 Specification for Reagent WaterD 3370 Practices for Sampling Water from Closed ConduitsD 3856 Guide for Good Laboratory Practices in Laborato-ries Engaged in Sampling and Analysis of WaterD 4210 Practice for Intralaboratory Quality Control Proce
10、-dures and a Discussion on Reporting Low-Level Data3D 4453 Practice for Handling of Ultra-Pure Water SamplesD 5810 Guide for Spiking into Aqueous SamplesD 5847 Practice for Writing Quality Control Specificationsfor Standard Test Methods for Water Analysis3. Terminology3.1 Definitions:3.1.1 For defin
11、itions of terms used in these test methodsrefer to Terminology D 1129.3.2 Definitions of Terms Specific to This Standard:3.2.1 analytical columnsa combination of one or moreguard columns followed by one or more separator columnsused to separate the ions of interest. It should be rememberedthat all o
12、f the columns in series contribute to the overallcapacity of the analytical column set.3.2.2 breakthrough volumethe maximum sample volumethat can be passed through a concentrator column before theleast tightly bound ion of interest is eluted.3.2.3 concentrator columnan ion exchange column usedto con
13、centrate the ions of interest and thereby increase methodsensitivity.3.2.4 eluantthe ionic mobile phase used to transport thesample through the exchange column.3.2.5 guard columna column used before the separatorcolumn to protect it from contaminants, such as particulatematter or irreversibly retain
14、ed materials.1These test methods are under the jurisdiction of ASTM Committee D19 onWater and are the direct responsibility of Subcommittee D19.03 on Sampling Waterand Water-Formed Deposits, Analysis of Water for Power Generation and ProcessUse, On-Line Water Analysis, and Surveillance of Water.Curr
15、ent edition approved May 1, 2009. Published June 2009. Originallyapproved in 1994. Last previous edition approved in 2004 as D 554204.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume info
16、rmation, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.6 ion chromat
17、ographya form of liquid chromatogra-phy in which ionic constituents are separated by ion exchangefollowed by a suitable detection means.3.2.7 resolutionthe ability of an analytical column toseparate constituents under specific test conditions.3.2.8 separator columnthe ion exchange column used tosepa
18、rate the ions of interest according to their retentioncharacteristics prior to their detection.3.2.9 suppressor devicea device that is placed betweenthe analytical columns and the detector. Its purpose is to inhibitdetector response to the ionic constituents in the eluant, so asto lower the detector
19、 background and at the same time enhancedetector response to the ions of interest.4. Significance and Use4.1 The anions fluoride, chloride, and sulfate have beenidentified as important contributors to corrosion of high pres-sure boilers, electric power turbines and their associated heatexchangers. M
20、any electric power utilities attempt to reducethese contaminants in their boiler feed water to less than 1g/L.4.2 In the semiconductor manufacturing process these ions,among others, have been identified as a cause of low productyield and, thus, must be monitored and controlled to levelssimilar to th
21、ose required by the electric power industry.4.3 Low molecular weight organic acids, such as acetate andformate, have been found in many steam generator feed watersand condensates. They are believed to come from the hightemperature breakdown of organic matter found in boiler makeup water. It is felt
22、that these organic acids promote corrosion bylowering the pH of boiler waters and may even be corrosivethemselves.4.4 Such low molecular weight organics may also beproduced when ultraviolet light is used to produce bacteria-freewater for semiconductor processing. Such polar organic con-taminants are
23、 suspected of causing reduced semiconductoryields.4.5 Phosphates are commonly added to drum boilers in thelow mg/L level to precipitate calcium and magnesium andthereby prevent scale formation. Ion chromatography can beused to monitor the concentration of such chemicals in boilerwater, as well as de
24、tect unwanted carry-over into the steam.5. Reagents5.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where
25、such specifications are available.45.1.1 Other grades may be used, provided it is first ascer-tained that the reagent is of sufficiently high purity to permit itsuse without lessening the accuracy of the determination.5.2 Purity of Water Unless otherwise indicated, refer-ences to water shall be unde
26、rstood to mean reagent waterconforming to Specification D 1193, Type I. Column life maybe extended by passing Type I water through a 0.22 m filterprior to use. Freshly prepared water should be used for makingthe low level standards intended for calibration. The detectionlimits of this method will be
27、 limited by the purity of the waterand reagents used to make the standards. The purity of thewater may be checked by use of this method. Anion concen-trations of less than 0.2 ppb each, is typical of Type I water.6. Sampling6.1 Collect samples in accordance with Practice D 1066,Specification D 1192,
28、 Practice D 3370, and Practice D 4453,asapplicable.6.2 Collect samples in polystyrene bottles that should befilled to overflow and capped, so as to exclude air. Glasssample bottles should not be used, as they can contribute ioniccontamination.6.3 Samples should be analyzed within 48 h of sampling.Wh
29、en acetate, formate or phosphate data are required, refrig-erate at 4C upon sampling.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for
30、 LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.FIG. 1 Anions by Test Method AD 5542 04 (2009)26.4 To prevent added ionic contamination, no preservationor filtration of the sample
31、shall be done.TEST METHOD ACHLORIDE, PHOSPHATE, ANDSULFATE7. Scope7.1 This test method is optimized for the quantitativedetermination of trace levels of chloride, phosphate, andsulfate. Anions such as fluoride, acetate, and formate can bedetected by this method, but are not reliably resolved fromeac
32、h other. See Fig. 1 for a typical chromatogram.7.2 Using a concentrated sample volume of 20 mL, the testmethod is applicable in the range outlined in Section 1. Therange of this test method may be extended by concentrating asmaller or a larger sample volume. Be sure not to exceedconcentrator column
33、breakthrough volume (see annex).8. Summary of Test Method8.1 A flow diagram of an ion chromatograph is shown inFig. 2. With the sampling valve in the load position, the desiredvolume of sample (for example, 20 mL) is pumped through aconcentrator column where the anions of interest are trapped.The sa
34、mpling valve is then switched to the inject position andthe pumped eluant, containing sodium carbonate and bicarbon-ate, sweeps these anions through the analytical columns wherethey are separated according to their retention characteristicsrelative to the anions in the eluant. The eluant stream next
35、passes through a suppressor where all cations are exchangedfor hydrogen ions. This converts the carbonate and bicarbonatein the eluant to the poorly ionized carbonic acid, thus reducingthe background conductivity.8.1.1 This also converts the anions to their acid form, thusenhancing their conductivit
36、y. The eluant stream then passesthrough an electrical conductivity detector, where the separatedanions are detected. A strip chart recorder and/or a chromato-graphic integrator is used for data presentation.8.2 The anions are identified based on their retention times,when compared to known standards
37、. Quantitation is accom-plished by measuring the peak height or area and comparing itto a calibration curve generated from known standards.9. Interferences9.1 When working at microgram per litre concentrationsand lower, contamination can be a very serious problem.Extreme care must be exercised in al
38、l phases of the test method(sample collection, storage, and analysis) to eliminate contami-nation.9.2 As with other types of chromatography, if one of thesample components is present at very high concentrationlevels, it may interfere by causing a very large peak on thechromatogram that could mask ot
39、her peaks present. This typeof interference may normally be minimized by dilution of thesample, depending on the concentration of other anions.9.3 When loading concentrator columns, high concentra-tions of certain anions may cause low breakthrough volumes ofother anions. These certain anions may act
40、 as eluants anddisplace other anions from the concentrator column. See annexto determine breakthrough volume. Do not attempt to concen-trate a volume of sample greater than 80 % of the breakthroughvolume.9.4 Samples containing high (mg/L) concentrations of am-monia, morpholine, or other additives wh
41、ich raise the hydrox-ide concentration (pH) of the sample may cause low break-through volumes. This problem may be avoided by taking suchsamples after the cation resin of a cation conductivity detector.10. Apparatus10.1 Ion ChromatographThe ion chromatograph shouldhave the following components assem
42、bled, as shown in Fig. 2.10.1.1 Eluant and Regenerant Containers.10.1.2 Eluant Pump, capable of delivering 2 to 5 mL/min ofeluant at a pressure of up to 2000 psig. Wetted parts of thepump should be nonmetallic, so as not to contaminate theconcentrator or analytical columns with metals, or both.10.1.
43、3 Sample Pump, capable of delivering up to 5 mL/minof sample at a pressure of at least 200 psig. Wetted parts of thepump should be nonmetallic, so as not to contaminate theconcentrator and/or analytical columns with metals.10.1.4 Concentrator ColumnAnion exchange columnwith sufficient capacity to co
44、ncentrate at least 20 mL of samplebefore reaching chloride breakthrough.10.1.5 Guard Column Anion exchange column, typicallyof the same anion exchange material used in the separatorcolumn. The purpose of this column is to protect the separatorcolumn from particulate matter and irreversibly retained
45、ma-terials.10.1.6 Separator ColumnAnion exchange column ca-pable of separating chloride from the injection void volume, aswell as resolving the anions chloride, phosphate, and sulfate.10.1.7 Suppressor ColumnA membrane based cation ex-changer which is continuously regenerated by a flow of dilutesulf
46、uric acid.FIG. 2 Schematic of an Ion ChromatographD 5542 04 (2009)310.1.8 DetectorA low-volume, flow-through,temperature-compensated electrical conductivity cell equippedwith a meter capable of reading from 0 to 1000 uS/cm on alinear scale.10.1.9 Recorder, compatible with the detector output with af
47、ull-scale response time of2sorless.10.1.10 IntegratorAn electronic integrator, such as isused with gas and liquid chromatographs, may be used toquantitate peak area, as well as peak height. The peak area datacan be used in the same way peak height is used to quantitateresults.10.1.11 Sample BottlesP
48、olystyrene culture bottles with atotal capacity of approximately 270 mL have been foundsatisfactory.10.1.12 The following is a summary of the columns andsuppressor components used in the collaborative study.Concentrator column: AG-4AGuard column: AG-4ASeparator column: AS-4ASuppressor device: Anion
49、MicroMembrane SuppressorAAAnion MicroMembrane Suppressor is a registered trademark of Dionex Corp.11. Reagents11.1 EluantDissolve 0.25 g of sodium bicarbonate (0.75millimolar) and 0.93 g of sodium carbonate (2.2 millimolar) inwater and dilute to 4 L with water. Other eluants may alsoprove to be acceptable, provided they give the proper resolu-tion between the component peaks.11.2 Suppressor RegenerantCautiously add 3 mL of con-centrated sulfuric acid to 4 L of water.11.3 Stock Solutions:11.3.1 Fluoride Solution, Stock (1.00 mL = 1.00 mg F)
