1、Designation: D 5542 04Standard 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, the year of last rev
2、ision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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, phosphate,and sulfat
3、e 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, they are notinc
4、luded 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 Detection2(Single Operator)(g/L) SectionsTest Method A: 715Chloride 024 0.8Phosphate 0393Sulfate 055 1.8Test Method B: 162
5、2Fluoride 014 0.7Acetate 0414 6.8Formate 0346 5.61.2 It is the users responsibility 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
6、The common practical range of Test Method B is asfollows: fluoride, 1 to 100 g/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 as thestandard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its
7、use. It is theresponsibility 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:4D 1066 Practice for Sampling SteamD 1129 Terminology Relating to WaterD 1
8、192 Specification for Equipment for Sampling Waterand Steam in Closed Conduits5D 1193 Specification for Reagent WaterD 2777 Practice for Determination of Precision and Bias ofApplicable Methods of Committee D19 on WaterD 3370 Practices for Sampling Water from Closed ConduitsD 3856 Guide for Good Lab
9、oratory Practices in Laborato-ries Engaged in Sampling and Analysis of WaterD 4210 Practice for Interlaboratory Quality Control Proce-dures and Discussion on Reporting Low-Level Data5D 4327 Test Method for Anions in Water by ChemicallySuppressed Ion ChromatographyD 4453 Practice for Handling of Ultr
10、a-Pure Water SamplesD 5810 Guide for Spiking Into Aqueous SamplesD 5847 Practice for the Writing of Quality Control Speci-fications for Standard Test Methods for Water Analysis3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in these test methodsrefer to Terminology D 1129.3.2 Defin
11、itions 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 of the columns in series contribute to the overallcapacity of the analytical col
12、umn 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 concentrate the ions of interest and thereby increase methodsensitivity.3.2.4 elua
13、ntthe ionic mobile phase used to transport thesample through the exchange column.1These test methods are under the jurisdiction of ASTM Committee D19 onWater and are the direct responsibility of Subcommittee D19.03 on Sampling ofWater and Water-Formed Deposits, Surveillance of Water, and Flow Measur
14、ementof Water.Current edition approved June 1, 2004. Published June 2004. Originallyapproved in 1994. Last previous edition approved in 1994 as D 5542 94 (1999)e1.2Limit of detection is lowest measurable concentration not reportable as zero at99 % level of confidence as per EPRI study as cited in Se
15、ctions 15 and 22.3Insufficient data to calculate limit of detection.4For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM w
16、ebsite.5Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.5 guard columna column used before the separatorcolumn to protect it from contaminants, such as particulatematter or irreversibly retained materials.3.2.6 ion chro
17、matographya 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 tos
18、eparate 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 detec
19、tor 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
20、. Many 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
21、 those 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 fe
22、lt 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
23、are 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
24、 detect 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,whe
25、re such specifications are available.65.1.1 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 u
26、nderstood 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
27、 be 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 11
28、92, 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
29、.When acetate, formate or phosphate data are required, refrig-erate at 4 Celsius upon sampling.6.4 To prevent added ionic contamination, no preservationor filtration of the sample shall be done.TEST METHOD ACHLORIDE, PHOSPHATE, ANDSULFATE7. Scope7.1 This test method is optimized for the quantitative
30、determination of trace levels of chloride, phosphate, andsulfate. Anions such as fluoride, acetate, and formate can bedetected by this method, but are not reliably resolved fromeach other. See Fig. 1 for a typical chromatogram.7.2 Using a concentrated sample volume of 20 mL, the testmethod is applic
31、able 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 breakthrough volume (see annex).8. Summary of Test Method8.1 A flow diagram of an ion chromatograph is shown inFig. 2. W
32、ith the sampling valve in the load position, thedesired volume of sample (for example, 20 mL) is pumpedthrough a concentrator column where the anions of interest aretrapped. The sampling valve is then switched to the injectposition and the pumped eluant, containing sodium carbonateand bicarbonate, s
33、weeps these anions through the analyticalcolumns where they are separated according to their retentioncharacteristics relative to the anions in the eluant. The eluantstream next passes through a suppressor where all cations areexchanged for hydrogen ions. This converts the carbonate andbicarbonate i
34、n the eluant to the poorly ionized carbonic acid,thus reducing the background conductivity.8.1.1 This also converts the anions to their acid form, thusenhancing their conductivity. The eluant stream then passes6Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Wa
35、shington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.D 5542
36、 042through 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. Quantitation is accom-plis
37、hed 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 all phases of the test method(
38、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 other peaks present. This type
39、of 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 as eluants anddisplace othe
40、r 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 which raise the hydrox-ide con
41、centration (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 assembled, as shown in Fig. 2.10.
42、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.10.1.3 Sample Pump, capable of de
43、livering 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 concentrate at least 20 mL of
44、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 ma-terials.10.1.6 Separator
45、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 dilutesulfuric acid.FIG. 1 Anions by T
46、est Method AFIG. 2 Schematic of an Ion ChromatographD 5542 04310.1.8 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 afull-s
47、cale 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 BottlesPolyst
48、yrene 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 Micro
49、Membrane7Suppressor11. 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)Dissolve 2.210 g of sodium fluoride (NaF) in water and diluteto 1 L with water
