1、Designation: D 2332 08Standard Practice forAnalysis of Water-Formed Deposits by Wavelength-Dispersive X-Ray Fluorescence1This standard is issued under the fixed designation D 2332; 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 This practice covers X-ray spectrochemical analysis ofwater-formed deposits.1.2 The practice is applicable t
3、o the determination ofelements of atomic number 11 or higher that are present insignificant quantity in the sample (usually above 0.1 %).1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to e
4、stablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 887 Practices for Sampling Water-Formed DepositsD 1129 Terminology Relating to WaterD 1193 Specification for Reagent WaterE11 Specifi
5、cation for Wire Cloth and Sieves for TestingPurposes3. Terminology3.1 For definitions of terms used in this practice, refer toTerminology D 1129.4. Summary of Practice4.1 The sample or its fusion with a suitable flux is powderedand the powder is compacted (mounted). The mount is thenirradiated by an
6、 X-ray beam of short wavelength (high energy).The characteristic X rays of the atom that are emitted orfluoresced upon absorption of the primary or incident X raysare dispersed, and intensities at selected wavelengths aremeasured by sensitive detectors. Detector output is related toconcentration by
7、calibration curves or charts.4.2 The K spectral lines are used for elements of atomicnumbers 11 to 50. Whether the K or L lines are used for theelements numbered 51 or higher depends on the availableinstrumentation.5. Significance and Use5.1 Certain elements present in water-formed deposits areident
8、ified. Concentration levels of the elements are estimated.5.2 Deposit analysis assists in providing proper water con-ditioning.5.3 Deposits formed from or by water in all its phases maybe further classified as scale, sludge, corrosion products, orbiological deposits. The overall composition of a dep
9、osit orsome part of a deposit may be determined by chemical orspectrographic analysis; the constituents actually present aschemical substances may be identified by microscope or X-raydiffraction studies. Organisms may be identified by micro-scopical or biological methods.6. Apparatus6.1 Sample Prepa
10、ration Equipment:6.1.1 Fusion Crucibles, prepared from 25-mm (1-in.)commercial-grade graphite rods. The dimensions shall be 29mm (118 in.) high, an inside diameter of 19 mm (34 in.), and acavity 22 mm (78 in.) deep.6.1.2 Pulverizers, including an agate or mullite mortar andpestle, minimum capacity 2
11、5 ml.6.1.3 SievesNo. 100 (150-m) and No. 270 (53-m) asspecified in Specification E11.6.1.4 CompactorsA press, equipped with a gauge en-abling reproducible pressure, is recommended.6.2 Excitation Source (X-ray Tube):6.2.1 Stable Electrical Power Supply (61 %).6.2.2 Source of high-intensity, short-wav
12、e-length X rays.6.3 Sample Housing (Turret).6.4 SpectrometerBest resolution of the spectrometer andbest sensitivity are not simultaneously attainable; a compro-mise is effected to give adequate values for each.6.4.1 Collimating System.1This practice is under the jurisdiction of ASTM Committee D19 on
13、 Water andis the direct responsibility of Subcommittee D19.03 on Sampling Water andWater-Formed Deposits, Analysis of Water for Power Generation and Process Use,On-Line Water Analysis, and Surveillance of Water.Current edition approved Oct. 1, 2008. Published November 2008. Originallyapproved in 196
14、5. Last previous edition approved in 2003 as D 2332 84 (2003).2For 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 website
15、.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.4.2 Spectrogoniometer.6.4.3 Analyzing Crystal and HolderThe choice of theanalyzing crystal is made on the basis of what elements mustbe determined; for example, a gypsum or an ammoni
16、umdihydrogen phosphate crystal can be used for determiningmagnesium but lithium fluoride is much superior for copperand iron (high-intensity diffracted secondary rays and conse-quently greater sensitivity and potential precision). A salt,sodium chloride (NaCl), crystal is frequently employed forgene
17、ral use, being applicable over a broad range and producingintense lines and medium broadening.6.4.4 Counter-Tube Support.6.5 Evacuating or Flushing System.6.6 Measuring System:6.6.1 Detector (of which the principal types are the Geigercounter, scintillation counter, and flow-proportional counter).6.
18、6.2 Amplifiers (Including Preamplifier), Rate Meter, Re-corder, Scaler, and Printout.6.6.3 Zeroing, Gain, and Sequence Controls.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifi
19、cations of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.7.2
20、 Purity of Waterreference to water shall be understoodto mean water that meets or exceeds the quantitative specifi-cations for Type I or Type II reagent water conforming toSpecification D 1193, Section 1.1.7.3 Detector Gas, usual composition 90 % argon, 10 %methane (other compositions are used); usu
21、ally used withflow-proportional counter for lines of longer wavelength (0.2nm or greater).7.4 Gallium Oxide, spectrographic grade (frequently used asa convenient internal standard).7.5 Helium Gas, commercial grade, for the spectrometerflushing system, when vacuum or air paths are not used.7.6 Sodium
22、 and Lithium Borates(Na2B4O7and Li2B4O7),commonly used as fluxes for the sample.8. Sampling8.1 Collect the sample in accordance with Practices D 887.9. Preparation of Sample9.1 Reduce the entire sample of deposits to about 100 g(drying, degreasing, and crushing if necessary) and grind thissubsample
23、to a powder that will pass a No. 100 (150-m) sieve.9.2 Mix the powdered sample thoroughly and remove about10 g for X-ray fluorescence testing (Note 1). Fuse a weighedamount with a weighed amount of a suitable flux (2 to 10 g offlux/g of sample) to present a reproducible surface compositionto the X-r
24、ay beam.NOTE 1At least semiquantitative results can be obtained more quicklyby compacting (mounting) the test portion (9.3 and 9.4) and proceeding inaccordance with Sections 10, 11, and 12. The decrease in samplepreparation will actually result in improved accuracy in some instances.9.3 Grind not mo
25、re than 10 g of the material prepared forX-ray analysis (sample or fusion) to pass a No. 270 (53-msieve).9.4 Make duplicate wafers (or suitable mounts for theparticular equipment that will be used) by compacting thepowdered sample (precision and accuracy are improved bybriquetting).An internal stand
26、ard is frequently added by fusionto the material to be compacted. Some samples may require abinder (generally organic and added in minimum concentra-tion) for reproducible packing and a smooth surface.10. Preparation of Apparatus10.1 Follow the manufacturers instructions for the initialassembly, con
27、ditioning, and preparation of the fluorescentX-ray apparatus.10.2 Follow the manufacturers instructions with respect tocontrol settings.11. Excitation and Exposure11.1 Position the mounted sample in the special chamberprovided for this purpose; avoid touching or otherwise con-taminating the sample s
28、urface. Produce and record the spec-trum at the setting or settings recommended for the instrument.Prepare and analyze duplicate mounts for all samples (makeduplicate readings on each mount).11.2 Radiation MeasurementsMake radiation measure-ments for each component of concern using Table 1 as a guid
29、eto the frequencies of interest.NOTE 2See also Bureau of Mines Information Circular No. 7725,which lists the 2-theta values for characteristic spectral lines when usingthe analyzing crystals NaCl, lithium fluoride (LiF), and quartz.3Reagent Chemicals, American Chemical Society Specifications, Americ
30、anChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC)
31、, Rockville,MD.TABLE 1 Emission Spectra and Recommended CrystalsElement Recommended CrystalAWave-lengthBAluminum gypsum 8.320Calcium lithium fluoride 3.353Copper lithium fluoride 1.539Iron lithium fluoride 1.934Lead lithium fluoride 1.172BMagnesium gypsum 9.869Phosphorus pentaerythritol tetraacetate
32、 6.142Potassium lithium fluoride 3.735Silicon pentaerythritol tetraacetate 7.111Sodium potassium acid phthalate 11.885Sulfur pentaerythritol tetraacetate 5.362Zinc lithium fluoride 1.434AUpdated to June, 1964; a production instrument, equipped with mountedcrystals, might conveniently use lithium flu
33、oride, pentaerythritol tetraacetate, andpotassium acid phthalate.BEmission wavelengths in kX units (1 kX unit = 1.002 ); the wavelength forlead is the L alpha-1 line and the others are averages of the K alpha-1 and -2 lines.D233208212. Calibration and Standardization12.1 Semiquantitative evaluations
34、 of the concentration ofeach component may be obtained directly by reference tostandardization curves prepared from data obtained by expos-ing samples containing known quantities of these components.12.2 More accurate evaluations can be made by preparingspecial standards containing the same componen
35、ts as thesample in the ratios indicated by the semiquantitative determi-nations. These special standards can frequently be used tocalculate correction factors for the calibration curves to mini-mize interference effects of the other components of thesample.12.3 Internal standards may be used to prov
36、ide directcomparison.13. Analytical Values13.1 Average the results obtained for each component fromat least two exposures of each mounted sample. Use theseaveraged values to read estimated concentrations from pre-pared calibration curves, charts, or tables.14. Statistical Values14.1 Precision of Ins
37、trumentThe precision of the instru-ment shall be determined from replicate measurements (10 to20) on a single prepared sample without moving the sample.This precision shall be reported as the standard deviation of theinstrument and is obtained as the usual square root of thesummated deviations squar
38、ed divided by 1 less than thenumber of replicate measurements.14.2 Precision of TechniqueCalculate the standard devia-tion of the method from duplicate measurements on 10 to 20samples over at least 3 days, removing and resetting the samplebefore each new series of measurements. The standard devia-ti
39、on of this technique is the square root of the summateddeviations squared divided by 4 times the number of analyses.14.3 Coefficient of variation of the practice is obtained bymultiplying the standard deviation by 100 and dividing by theaverage concentration in percent.15. Precision and Bias15.1 A p
40、recision and bias statement is not applicable. Referto Sections 12 and 14 for estimation of element concentrationand evaluation of instrument-specific precision.16. Keywords16.1 deposits; elemental analysis; scale; X-ray fluorescenceASTM International takes no position respecting the validity of any
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42、sion at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your
43、comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyri
44、ghted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D2332083
