1、Designation: D 3267 91 (Reapproved 2005)Standard Test Method forSeparation and Collection of Particulate and Water-SolubleGaseous Fluorides in the Atmosphere (Filter and ImpingerMethod)1This standard is issued under the fixed designation D 3267; the number immediately following the designation indic
2、ates the year oforiginal adoption or, in the case of revision, the year of last revision. 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 This test method provides a procedure for
3、separationand collection on a chemically treated filter and in an impingerof particulate and water-soluble gaseous fluoride in the atmo-sphere. The sampling rate may vary from 30 L/min (1.0ft3/min) to 15 L/min (0.5 ft3/min) for longer sampling periodsdepending on the atmospheric fluoride concentrati
4、on. This testmethod is not intended to be applied to gaseous fluorinecompounds that are not water-soluble1.2 There are several limitations of the test method:1.2.1 Although the acid-treated, medium retentive, prefilterhas been shown to allow passage of HF, it will restrict passageof particulate matt
5、er only as small as about 1 m. Thus, smallerparticulate matter may pass through the filter and be collectedin or pass through the impingers.1.2.2 The maximum sample volume to be taken using thistest method prior to changing the acid-treated prefilter isrecommended as 12 m3. This recommendation is ma
6、de tominimize any effects due to particulate matter build-up.1.3 The values stated in SI units are to be regarded as thestandard. The inch-pound units given in parentheses are forinformation only.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use
7、. 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.For specific precau-tionary statements, see 7.2 and 7.4.6.2. Referenced Documents2.1 ASTM Standards:2D 1071 Test Method
8、s for Volumetric Measurement of Gas-eous Fuel SamplesD 1193 Specification for Reagent WaterD 1356 Terminology Relating to Sampling and Analysis ofAtmospheresD 1357 Practice for Planning the Sampling of the AmbientAtmosphereD 2009 Practice for Collection by Filtration and Determi-nation of Mass, Numb
9、er, and Optical Sizing of Atmo-spheric Particulates3D 3268 Test Method for Separation and Collection of Par-ticulate and Gaseous Fluorides in theAtmosphere (SodiumBicarbonate-Coated Glass Tube and Particulate FilterMethod)D 3269 Test Methods for Analysis for Fluoride Content ofthe Atmosphere and Pla
10、nt Tissues (Manual Procedures)D 3270 Test Method for Analysis for Fluoride Content ofthe Atmosphere and Plant Tissues (SemiautomatedMethod)E 337 Test Method for Measuring Humidity with a Psy-chrometer (the Measurement of Wet- and Dry-Bulb Tem-peratures)3. Terminology3.1 DefinitionsFor definitions of
11、 terms used in this testmethod, refer to Terminology D 1356.4. Summary of Test Method4.1 Air is drawn through an air inlet tube (see PracticeD 1357) and is first passed through an acid-treated prefilter toremove particulate matter that may contain fluoride and thenthrough an impinger to remove water
12、-soluble fluorides.4.2 The prefilter and impinger solution are removed fromthe sampling system at the end of the selected sampling periodand taken to an analytical work area and analyzed by either a1This test method is under the jurisdiction of ASTM Committee D22 on AirQuality and is the direct resp
13、onsibility of Subcommittee D22.03 on AmbientAtmospheres and Source Emissions.Current edition approved March 1, 2005. Published May 2005. Originallyapproved in 1973. Last previous edition approved in 2000 as D 3267 - 91 (2000)e1.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or
14、contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.potenti
15、ometric or photometric method (1, 2, 3, 4).4See TestMethods D 3269 and D 3270.5. Significance and Use5.1 This test method provides a means of separation andcollection of particulate and water soluble gaseous fluoride andprovides samples that are convenient to analyze.6. Interferences6.1 Particulate
16、metallic salts, such as those of aluminum,iron, calcium, magnesium or rare-earth elements, may reactwith and remove some or all of the water-soluble gaseousfluoride on the prefilter. If interfering quantities of suchparticulate metallic salts are present, the use of Test MethodD 3268 is recommended
17、because the acidic fluoride gases arecollected prior to the filter.6.2 Aluminum or certain other metals or phosphates caninterfere with subsequent analyses by photometric or electro-metric methods. These potential interferences are discussed inTest Methods D 3269 and D 3270.7. Apparatus7.1 Standard
18、Impinger,(Fig. 2C) for sampling coveringperiods up to 3 h. When sampling is initiated, the collectingimpinger shall contain 75 to 150 mLof reagent water (see 8.2).7.2 Impinger, Modified, Standard, Smith-Greenburg (Fig.1). For sampling periods from 3 to 72 h, see Fig. 1 and Fig. 3C.(WarningIf a diffe
19、rent size impinger is used, the recovery ofthe sample should be determined.)7.3 Water Level Control Device, for use with long-termsampling train (Fig. 3).7.3.1 Liquid Level Controller. (See Fig. 3G and H.)7.3.2 Control Valve, solenoid-activated. (See Fig. 3D.)7.3.3 Water Reservoir, equipped with a g
20、uard tube contain-ing an alkaline reagent to prevent fluoride contamination. (SeeFig. 3E and F.)7.4 Sampling Equipment (see Fig. 1, Fig. 2, and Fig. 3 fordimensions and details).7.4.1 Sampling Tube (see Fig. 2A), constructed of a1225-mm (4-ft) length of a material that is inert to theatmosphere bein
21、g sampled. (See Note 1.)NOTE 1Stainless steel coated with plastic material is preferred be-cause of its rigidity and permanence. Plastic materials which have beenshown to have a low absorbance for gaseous fluorides are polytetrafluo-roethylene, polyethylene, polypropylene and polychlorotrifluoroethy
22、lene.However, high air velocities through some types of plastic tubing maycreate a static charge and cause deposition of particulate matter. Conse-quently, if plastic is selected for use, it should be tested to demonstrate thatthis effect does not occur to a significant degree.7.4.2 Filter Holder, s
23、tainless steel or polypropylene, (Fig.2B), to hold the acid-treated prefilter. (See Note 2.)NOTE 2Note that filter changes are recommended after 12 m3aresampled.7.4.3 Mercury Manometer (Fig. 2E), for the determinationof pressure in the metered sampling line. A calibrated vacuumgage is also satisfact
24、ory.7.4.4 Dry Test Meter (Fig. 2F), for measuring the totalvolume sampled.7.4.5 Thermometer, to sense the temperature of the sampledgas (Fig. 2G). ASTM thermometer 33C has been found usefulfor this application.7.4.6 Control Valve (Fig. 2H), to adjust the sample ratethrough a dry test meter. (See 7.4
25、.4.) (WarningExercise careto see that all sampling apparatus is clean and free ofcontamination. Clean with a detergent low in fluoride andphosphate, followed by thorough rinsing with water (see 8.2.)7.4.7 Vacuum Pump (see Fig. 2J), capable of a 30 L/min (1ft3/min) sampling rate and capable of contin
26、uous operationover the maximum sample period selected under the environ-mental conditions imposed by the sampling location.8. Reagents8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests.All reagents shall conform to the specificationsof the Committee on Analytical Reagents of the
27、 AmericanChemical Society, where such specifications are available.58.2 Purity of WaterWater shall be Type II reagent waterconforming to Specification D 1193. Additionally, test thewater with a specific ion electrode or by concentration andphotometric analysis to demonstrate that it contains less th
28、an0.005 g/mL of fluoride.8.3 Alcoholic Citric Acid Solution (0.1 N)Dissolve 4.203g of citric acid monohydrate in 200 mL of 95 % ethyl alcohol.4The boldface numbers in parentheses refer to the references at the end of thisstandard.5Reagent Chemicals, American Chemical Society Specifications, American
29、Chemical Society, Washington, 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. Pharmacopeial Convention, Inc. (USPC),
30、Rockville,MD.FIG. 1 Modified Standard ImpingerD 3267 91 (2005)28.4 Chemically treated filters are used as the prefilter. (See10.1.)8.5 Sodium Hydroxide Solution (5N)Dissolve 200 g ofsodium hydroxide (NaOH) in 250 mL of water in a 1-Lvolumetric flask, swirl to mix, cool and dilute to 1000 mL withwate
31、r. Mix thoroughly.8.6 Sodium Hydroxide Solution (1.0 N)Dissolve 40.0 g ofNaOH in 250 mL of reagent water in a 1000-mL volumetricflask. Swirl to mix, cool, and dilute to 1000 mL with reagentwater. Mix thoroughly.8.7 Sulfuric Acid (1.0 N)Add 28.0 mL of concentratedH2SO4(sp gr 1.84) to 250 mL of reagen
32、t water in a 1000-mLvolumetric flask. Swirl to mix, cool, and dilute to 1000 mLwith reagent water. Mix thoroughly.8.8 Total Ionic Strength Adjustment Buffer (TISAB)Add57 mL of glacial acetic acid, 58 g of sodium chloride (NaCl)and 4.0 g of CDTA (1,2-cyclohexylene-dinitrilo)tetraaceticacid) to 500 mL
33、 of distilled water. Stir and add 5 NNaOHsolution (see 8.5) slowly until the pH is between 5.0 and 5.5.Cool and dilute to 1 L.8.9 TISAB (1:1)Dilute the full strength TISAB (see 8.8)1:1 with an equal amount of water.9. Calibration9.1 Calibrate the dry test meter (see 7.4.4) in accordancewith Test Met
34、hods D 1071.10. Procedure10.1 Treatment of Prefilter:10.1.1 Immerse medium retentive prefilter (WarningExercise care to see that all sampling apparatus is clean andfree of contamination. Clean with a detergent low in fluorideand phosphate, followed by thorough rinsing with water (see8.2.) in the alc
35、oholic citric acid solution (0.1 N) (see 8.3) andplace under an infrared lamp to dry. After drying and prior touse, store the treated filter in a sealed container to preventcontamination.NOTE 3If the person using this test method demonstrates a require-ment for prefilter of higher retentivity, other
36、 filters may be used.Membrane filters, if used, require reduction of the alcohol content of thealcoholic citric acid solution to 65 % to prevent deformation of the pores.10.2 Sampling:10.2.1 Test the System for Leaks:10.2.1.1 Fill the impinger with the required volume ofreagent water (see 8.2) that
37、will be utilized during sampling.10.2.1.2 Turn on the vacuum pump (see 7.4.7) and developa vacuum slightly greater than that required for the desiredsampling rate.NOTE 4For short term sampling (3 h or less), utilize a flow rate of 30L/min (1 ft3/min). For long-term sampling (24 to 72 h), a flow rate
38、 of 15L/min (0.5 ft3/min) shall be used with the modified standard impinger (seeA Sampling tube F MeterB Filter holder G ThermometerC Standard impinger H Metering valveD Deminster (dry-impinger) J Vacuum pumpE ManometerSI Equivalentsin.91634 45836mm 14 19 102 127 203 914FIG. 2 Diagram of a Sample Tr
39、ain for Short-Term Sampling of Atmospheric FluoridesD 3267 91 (2005)37.2) and the water level controller (see 7.3) to compensate for solutionevaporation.10.2.2 During the sampling period, record the time,vacuum, and meter reading at the beginning and end of thesampling period. Also record barometric
40、 pressure in accor-dance withTest Method D 3270 and the ambient temperature atintervals during the sampling period.10.2.3 Use field blanks with each sample. (See Note 4.)NOTE 5Take two filters to the field and use one for sampling. Use thesecond filter as a field blank. Carry an impinger containing
41、150 mL ofdeionized water to the sampling site and treat in the same manner as thesample impingers except do not connect into a sample train. Use thisimpinger as a field blank.10.2.4 At the end of the sampling period, transfer the filterand impinger contents to suitable containers for transporting to
42、the work area where analyses are to be performed.10.3 See Practice D 1357 for guidance on sampling.11. Preparation of Samples for Fluoride Analysis11.1 Carry out the analysis in a work area with an atmo-sphere free of contamination by fluorides.11.2 Preparation of Impinger Solutions for Fluoride Ana
43、ly-sis:11.2.1 Measure the volume of liquid in the impinger byweight if a tare weight is available on the impinger or bytransferring to a tared polyethylene bottle and weighing thetotal contents after transfer. Record the weight of the liquidcontents. Mix the contents thoroughly.11.2.2 For Potentiome
44、tric Analysis:(Note 5 and Note 6).11.2.2.1 Transfer 10.0 mL of the sample into a cleanpolyethylene (or polypropylene or TFE-fluorocarbon) beakerand dilute an equal amount with TISAB buffer. (8.9)11.2.2.2 Analyze the aliquot using the potentiometric TestMethod D 3269.NOTE 6If the fluoride levels in t
45、he impinger solutions are lower thanthe sensitivities of the prescribed methods, then the solutions may beconcentrated for analysis as described inTest Methods D 3269 or analyzedas described in Note 6.NOTE 7In the potentiometric method, the sample may be spiked withan exactly measured amount of fluo
46、ride (for example: 0.4-mL of 0.01 mgF/mL standard NaF solution in 40 mL of final volume). This additionwould be used if required to raise the concentration to a more favorablepart of the response curve of the fluoride specific ion electrode. Theconcentration added will be deducted from the concentra
47、tion determined.11.2.3 For Semiautomated Analyses:11.2.3.1 Transfer the solution to an 8.5-mL sample cup.11.2.3.2 Analyze the sample using Method D 3270.11.3 Preparation of the Prefilter Used to Collect Particulatefor Fluoride Analysis:11.3.1 For Potentiometric Analysis:A Sampling tube F Guard tubeB
48、 Filter holder G Water level controllerC Modified standard impinger H Water level sensorD Control valve J Refer to Fig. 2 for Remainder of Sam-E Water-reservoir pling train following impinger CSI Equivalentsin.91634 45836mm 14 19 102 127 203 914FIG. 3 Diagram of a Modified Standard Impinger for Long
49、-Term Sampling of Atmospheric FluoridesD 3267 91 (2005)411.3.1.1 Place the filter in a clean polyethylene (or polypro-pylene or TFE-fluorocarbon) beaker. Add 10.0 mL of 1 NH2SO4(see 8.7), mix for a minimum of 5 min with a magneticstirrer, and allow to stand for 5 min.11.3.1.2 Add an equal volume of 1 NNaOH solution (see8.6) and mix. (See Note 7.)NOTE 8In any specific sampling program, confirm the quantitativerecovery of the fluoride content of the filter extraction with 1 N H2SO4(see8.7) (see Test Methods D 3269.)11.3.1.3 Add 20 mL of TISAB, (8.9) mix,
