1、Designation: C1301 95 (Reapproved 2014)Standard Test Method forMajor and Trace Elements in Limestone and Lime byInductively Coupled Plasma-Atomic Emission Spectroscopy(ICP) and Atomic Absorption (AA)1This standard is issued under the fixed designation C1301; the number immediately following the desi
2、gnation indicates 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 () indicates an editorial change since the last revision or reapproval.1. Scope1.1 The following test method cove
3、rs the use of inductivelycoupled plasma-atomic emission spectroscopy (ICP) andatomic absorption spectroscopy (AA) in the analysis of majorand trace elements in limestone and lime (calcined limestone).1.2 Table 1 lists some of the elements that can be analyzedby this test method and the preferred wav
4、elengths. Also seeU.S. EPA Methods 200.7 and 200.9.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibi
5、lity 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:2C51 Terminology Relating to Lime and Limestone (as usedby the Industry)D1193 Specification for Re
6、agent WaterE135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related MaterialsE863 Practice for Describing Atomic Absorption Spectro-metric Equipment (Withdrawn 2004)3E1479 Practice for Describing and Specifying Inductively-Coupled Plasma Atomic Emission Spectrometers2.2 U.S. EP
7、A Standards:Methods for the Determination of Metals in EnvironmentalSamples; U.S. EPA Methods 200.2, 200.7, and200.9; Smoley, C. K., 19924Method 6010 Inductively Coupled Plasma Method, SW-846,Test Methods for Evaluating Solid Waste53. Terminology3.1 DefinitionsDefinitions for terms used in this test
8、method can be found in Terminologies C51 and E135.3.2 Additional Definitions:3.2.1 total recoverable, ntrace element concentration inan unfiltered sample after heating in acid.3.2.2 total digestion, ncomplete digestion of a sample,including silica and silicate minerals, using the fusion-fluxmethod.4
9、. Summary of Test Method4.1 A sample, digested by either fusion or acid, is atomizedand passed into an excitation medium (a plasma in the case ofICP; a flame in the case ofAA). The resulting ions are analyzedby atomic spectroscopy. Elemental concentrations are deter-mined by graphically relating the
10、 emission/absorption at spe-cific wavelengths for an unknown sample to analytical curvesmade from reference standards of known composition.5. Significance and Use5.1 The presence and concentration of elements in lime andlimestone is important in determining product quality and itssuitability for var
11、ious uses. This test method provides a meansof measuring the major and trace element concentration in limeand limestone.6. Interferences6.1 ChemicalChemical interferences, most common inAA, arise from the formation of molecular compounds that1This test method is under the jurisdiction of ASTM Commit
12、tee C07 on Limeand Limestone and is the direct responsibility of Subcommittee C07.05 on ChemicalTests.Current edition approved July 1, 2014. Published July 2014. Originally approvedin 1995. Last previous edition approved in 2009 as C1301 95(2009). DOI:10.1520/C1301-95R14.2For referenced ASTM standar
13、ds, 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.3The last approved version of this historical standard is referenced onwww.astm.org.4Avai
14、lable from CRC Press, 2000 Corporate Blvd., N. W., Boca Raton, FL33431.5Available from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700,
15、West Conshohocken, PA 19428-2959. United States1cause absorbances at the wavelength of interest. This molecu-lar band spectral overlap can be minimized by buffering thesample with matrix modifiers (a Lanthanum additive, forexample), using standard additions techniques, matrix match-ing or by careful
16、 selection of operating conditions (forexample, using a hotter nitrous oxide/acetylene flame, selectingan alternate wavelength).6.2 PhysicalPhysical interferences are the result of theinconsistencies in the introduction of the sample into theinstrument, namely the transport and atomization/nebulizat
17、ionof the sample. These inconsistencies are a function of changingviscosity and surface tension, and are found primarily insamples of high-dissolved solids or high-acid concentrations.Physical interferences can be reduced by diluting the sampleand by the use of a peristaltic pump.6.3 SpectralSpectra
18、l interference, most common in ICP,consists of overlapping and unresolved peaks. Computersoftware, along with the analysis of the suspected interferingelement, can compensate for this effect. Using an alternatewavelength is also a solution. Another spectral interference iscaused by background, both
19、stray light and continuous spec-trum (continuous argon spectrum, for example). Backgroundcorrection adjacent to the analyte line will correct backgroundspectral interference.7. Apparatus7.1 Spectrometer.7.1.1 Inductively Coupled Plasma Emission Spectrometer(ICP)Either a scanning sequential or multi-
20、element simulta-neous type ICP, with resolution appropriate for the elements tobe analyzed. The optical path may be in air, vacuum or an inertgas. A detailed description of an ICP is given in PracticeE1479.7.1.2 Atomic Absorption Spectrometer (AA)An atomicabsorption spectrometer consisting of single
21、 or double beamoptics, a monochromator, photomultiplier detector, adjustableslits, a wavelength range from 190 to 800 nm, and provisionsfor interfacing with either a strip chart recorder or a computer.A simultaneous background correction system is also recom-mended. A detailed description of an AA i
22、s given in PracticeE863.7.1.2.1 Hollow Cathode LampsSingle hollow cathodelamps, one for each element. Multi-element hollow cathodelamps can be used but spectral interferences are possible.8. Reagents8.1 Purity of ReagentsReagents should conform to thespecifications of the Committee on Analytical Rea
23、gents of theAmerican Chemical Society as a minimum when such speci-fications are available.6The high sensitivity of both the ICPandAAmay require reagents of high purity. It is recommendedthat the reagents be of sufficiently high purity so as not tolessen the accuracy of the determination.8.2 Purity
24、of WaterAt minimum, water should conform toType II of Specification D1193.8.3 Stock SolutionsStandard stock solutions may be pur-chased or prepared from high purity metals or metal salts(Method 6010, SW-846; EPA Methods 200.7 and 200.9). Saltsshould be dried at 105C for 1 h, unless otherwise specifi
25、ed.8.4 Multi-element Calibration StandardsICP calibrationis most often performed using multi-element calibration stan-dards prepared from single element stock solutions. Prior topreparing the mixed standards, each stock solution should beanalyzed separately to determine possible spectral interferenc
26、eor the presence of impurities. Standards are combined in sucha way that they are chemically compatible (no precipitationoccurs) and do not cause spectral interferences. An example ofmulti-element combinations is given in EPA Method 200.7.8.5 Interference Check SampleInterference check samplesare ma
27、de from single element stock solutions at a concentrationlevel equal to that of the samples to be analyzed.8.6 Calibration BlankA calibration blank is prepared atthe same acid strength as that of the samples to be analyzed;usually 5 or 10 %. To prepare a 10 % nitric acid calibrationblank, add one vo
28、lume of nitric acid to nine volumes of water.This same blank can be used as the rinse solution for flushingthe system between standards and samples.6Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notli
29、sted 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), Rockville,MD.TABLE 1 Elements and Some Suggested WavelengthsAMajor Elements ICP Wa
30、velength, nm AA Wavelength, nmCalcium 317.933 (315.887)B422.7Magnesium 279.079 (285.213) 285.2Silicon 251.611 (288.160) 251.6Aluminum 308.215 (309.271) 309.3Iron 259.940 248.3Manganese 257.610 279.5Sodium 588.995 (589.59) 589.0Potassium 766.491 766.5Phosphorus 214.914 (213.618) .CStrontium 421.552 4
31、60.7Trace Elements ICP Wavelength, nm AA Wavelength, nmAntimony 206.833 217.6Arsenic 193.696 193.7Barium 455.403 (493.409) 553.6Beryllium 313.042 234.9Boron 249.773 249.8Cadmium 226.502 (228.80) 228.8Chromium 267.716 (205.552) 357.9Cobalt 228.616 240.7 (242.5)Copper 324.754 324.8Lead 220.353 217.0 (
32、283.3)Molybdenum 202.030 (203.844) 313.3Nickel 231.604 (221.647) 232.0Selenium 196.090 196.0Silver 328.068 328.1Sulfur 180.731 (180.669) .CThallium 190.864 276.8Tin 189.989 235.5 (286.3)Vanadium 292.402 318.4Zinc 213.856 (202.551) 213.9AThe suggested wavelengths may vary for your particular instrume
33、nt.BNumbers in parentheses are alternate wavelengths.CNot recommended or not used.C1301 95 (2014)28.7 Reagent BlankThe reagent blank contains all thereagents in the same concentrations (including nitric acid) asthe samples to be analyzed. The reagent blank is carriedthrough the same processes as a s
34、ample for analysis.8.8 Nitric AcidHigh purity nitric acid is recommended.8.9 Lithium Tetraborate (Li2B4O7) Powder or LithiumMetaborate (LiBO2) Powder.8.10 Non-Wetting AgentSaturated solution of HydrogenBromide (HBr), Potassium Bromide (KBr) or Potassium Iodide(KI) as a non-wetting agent to prevent t
35、he flux from sticking tothe crucible.8.11 Lanthanum Chloride (LaCl3) PowderLanthanum isadded to samples for AA analysis as a releasing agent (forCalcium) and ionization suppressant (for Aluminum). Whenadded to the sample solution, Lanthanum will preferentiallyreact with potential interferents and “r
36、elease” the analyte. Inaddition, the Lanthanum will preferentially ionize relative toAluminum, aiding in the number of ground state Aluminumatoms. A typical Lanthanum additive is prepared by dissolving175 g LaCl3 in 1 L of water (equivalent to 100 g/L Lantha-num).9. Preparation of Apparatus9.1 Prepa
37、re and operate the spectrometer in accordance withthe manufacturers instructions. The present method assumesthat good operating procedures are followed. Design differ-ences between spectrometers make it impractical to specify therequired steps in detail here.10. Calibration and Standardization10.1 A
38、llow a warm-up time of at least 30 min. Operate thespectrometer according to the operation manual for the instru-ment.10.2 Calibrate the instrument by aspirating the blank andstandards. A10 % by volume HNO3rinse solution is aspiratedfor a minimum of 60 s between each standard. Most newsystems are co
39、ntrolled by computer. The computer will estab-lish the slope, intercept and correlation coefficients for eachelement. Some suggested wavelengths are given in Table 1 andEPA Methods 200.2, 200.7, and 200.9.10.3 A peristaltic pump is recommended for aspiratingstandards and samples. The peristaltic pum
40、p will reducephysical interferences caused by changes in specimen viscosityand concentration (transport processes).11. Sample Preparation11.1 Major ElementsSamples for major element analysisare prepared for total digestion using lithium tetraborate orlithium metaborate as a flux. Major elements incl
41、ude Calcium,Magnesium, Silicon,Aluminum, Iron, Manganese, Sodium andPotassium. Trace elements such as Lead, Arsenic, Seleniumand Antimony will partially volatilize using this fusion methodand it is therefore not recommended for trace element analysis.11.1.1 Take a representative minus 100 mesh sampl
42、e splitand dry at 105C for 2 h.11.1.2 Weigh 0.25 g of dried sample in a graphite orplatinum crucible. Then weigh 1.00 g of lithium metaborate inthe crucible. Add a few drops of non-wetting agent if needed.Mix the sample and lithium metaborate (the flux) well. Coverthe mixed sample-lithium metaborate
43、 with an additional 0.50 gof lithium metaborate. This will give a total sample-flux ratioof 1:6.11.1.3 Place a lid (optional) on the crucible prepared in11.1.2 and place in a muffle furnace at 1000C for 30 min.Gently agitate the molten contents of the crucible at least onceduring the 30 min heating.
44、11.1.4 Add 12.5 mL of concentrated nitric acid and 40 mLof water to a clean 250 mL wide-mouth plastic bottle.11.1.5 When the 30 min heating in 11.1.3 is complete,quickly pour molten contents of the crucible into the plasticbottle described in 11.1.4. The water will bubble and sizzle.Quickly put the
45、lid on the plastic bottle and shake. To aid indigestion place the bottle in a warm ultrasonic bath.11.1.6 The contents of the plastic bottle can either bequantitatively transferred to a 250 mL volumetric flask anddiluted to volume or diluted to volume by weight (that is, 1mL = 1 g) in the same 250 m
46、L plastic bottle it was digested in.Keep in mind, however, that the standards need to be made inthe same manner as the samples. Add 10 mL Lanthanumadditive to samples for AA analysis (10 mL addition is part ofthe dilution to volume). Filtering is not necessary.11.2 Trace ElementsSamples for trace el
47、ement analysisare prepared using hydrochloric acid (1:5 or 1+4) and nitricacid (1:2 or 1+1). The trace elements concentrations deter-mined by this method are termed “total recoverable” (that is,components not digested in hot acid are not recovered). Traceelements include, but are not limited to, Ant
48、imony, Arsenic,Barium, Beryllium, Boron, Cadmium, Chromium, Cobalt,Copper, Lead, Molybdenum, Nickel, Selenium, Silver,Strontium, Thallium, Tin, Vanadium, and Zinc.11.2.1 Take a representative minus 100 mesh sample splitand dry at 105C for 2 h.11.2.2 Weigh 1.00 g of dried sample and transfer to a cle
49、anbeaker.11.2.3 Add 10 mL of dilute hydrochloric acid (see 11.2) and4 mL of dilute nitric acid (see 11.2). In the case of limestone,add the acids slowly so that the powdered sample will notsplatter on the sides of the beaker during its effervescentreaction with the acid. Cover the sample (a ribbed watch glassis best) and place on a hot plate. Heat at approximately 85Cfor 30 min. Boiling should be kept to a minimum.After 30 minallow the sample to cool. Then quantitatively transfer the liquidand any undissolved residue to a 100 mL volumetric flask.Dilut
