1、Designation: E367 09Standard Test Methods forChemical Analysis of Ferroniobium1This standard is issued under the fixed designation E367; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parenth
2、eses 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 chemical analysis offerroniobium having chemical compositions within the follow-ing limits:Element Concentration, %Aluminum
3、 2.00 maxCarbon 0.30 maxChromium 2.00 maxCobalt 0.25 maxLead 0.01 maxManganese 3.00 maxNiobium 40.00 to 75.00Phosphorus 0.05 maxSilicon 4.00 maxSulfur 0.03 maxTantalum 7.00 maxTin 0.15 maxTitanium 5.00 maxTungsten 0.50 max1.2 The test methods appear in the following order:SectionsSeparation of Niobi
4、um, Tantalum, and Titaniumby the Ion-Exchange Test Method10-16Titanium by the Photometric Test Method 0.05 % to 5.0 % 17-21Niobium by the Gravimetric Test Method 40 % to 75 % 22-23Tantalum by the Gravimetric Test Method 1 % to 7 % 24-25Tantalum by the Photometric Test Method 0.25 % to 1 % 26-301.3 T
5、he 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 theresponsibility of whoever uses this standard to consult andestabli
6、sh appropriate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.Specific precautionary statements are given in Section 6, andspecific warning statements in 11.1.2. Referenced Documents2.1 ASTM Standards:2A550 Specification for FerrocolumbiumE29 Prac
7、tice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE32 Practices for Sampling Ferroalloys and Steel Additivesfor Determination of Chemical CompositionE50 Practices for Apparatus, Reagents, and Safety Consid-erations for Chemical Analysis of Metals, Ores, andRel
8、ated MaterialsE60 Practice for Analysis of Metals, Ores, and RelatedMaterials by Molecular Absorption SpectrometryE135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related MaterialsE173 Practice for Conducting Interlaboratory Studies ofMethods for Chemical Analysis of Metals3E16
9、01 Practice for Conducting an Interlaboratory Study toEvaluate the Performance of an Analytical Method3. Terminology3.1 For definition of terms used in this test method, refer toTerminology E135.4. Significance and Use4.1 These test methods for the chemical analysis of metalsand alloys are primarily
10、 intended to test such materials forcompliance with compositional specifications such as Specifi-cation A550. It is assumed that all who use these test methods1These test methods are under the jurisdiction of ASTM Committee E01 onAnalytical Chemistry for Metals, Ores, and Related Materials and are t
11、he directresponsibility of Subcommittee E01.01 on Iron, Steel, and Ferroalloys.Current edition approved Oct. 1, 2009. Published November 2009. Originallyapproved in 1970. Last previous edition approved in 2003 as E367 03. DOI:10.1520/E0367-09.2For referenced ASTM standards, visit the ASTM website, w
12、ww.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.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM Interna
13、tional, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.will be trained analysts capable of performing common labo-ratory procedures skillfully and safely. It is expected that workwill be performed in a properly equipped laboratory.5. Apparatus, Reagents, and Phot
14、ometric Practice5.1 Apparatus, standard solutions, and other reagents re-quired for each determination are listed in separate sectionspreceding the procedure. Photometers shall conform to therequirements prescribed in Practice E60.5.2 Photometric practice prescribed in these test methodsshall confor
15、m to Practice E60.6. Hazards6.1 For precautions to be observed in the use of certainreagents in these test methods, refer to Practices E50.6.2 Specific warning statements are given in 11.1.7. Sampling7.1 For procedures for sampling the material, and forparticle size of the sample for chemical analys
16、is, refer toPractices E32.8. Rounding Off Calculated Values8.1 Calculated values shall be rounded off to the desirednumber of places as directed in Practice E29.9. Interlaboratory Studies9.1 These test methods have been evaluated in accordancewith Practice E173, unless otherwise noted in the precisi
17、on andbias section.NIOBIUM, TANTALUM, AND TITANIUM BY THEION-EXCHANGE TEST METHOD10. Scope10.1 These test methods cover the determination of nio-bium, tantalum, and titanium in ferroniobium from 40 % to75 %, 0.25 % to 7 %, and 0.05 % to 5.0 %, respectively.11. Summary of Test Method11.1 The sample i
18、s dissolved in a HCl-HF acid mixture andtransferred to an anion-exchange column. Titanium, iron, andother elements are eluted with anNH4Cl-HCl-HF acid mixture.This eluate is treated with boric acid (H3BO3) and cupferron,and the precipitate, containing the titanium, is ignited, fusedwith potassium hy
19、drogen sulfate, and leached in dilute H2SO4.The titanium is oxidized to the yellow pertitanate with hydro-gen peroxide. Photometric measurement is made at approxi-mately 410 nm. Niobium is removed by eluting with anammonium chloride-hydrofluoric acid mixture. Tantalum isremoved by eluting with an am
20、monium chloride-ammoniumfluoride solution adjusted to a pH of 5 to 6. The eluates aretreated with the H3BO3to complex the fluorides, and each ofthe elements, niobium and tantalum, is precipitated withcupferron, ignited, and weighed as the pentoxide. For tantalumbelow 1 %, zirconium is added as a gat
21、herer in the cupferronseparation and the tantalum is converted to the pyrogallolcomplex. Photometric measurement is made at approximately420 nm. (WarningHF produces very serious burns whichmay or may not be painful on first contact. Such burns oftendamage bone and other tissue within the body. Stand
22、ardprocedure is to use gloves and protective clothing whenhandling this reagent. After the material is added, the closedcontainer, gloves, and all surfaces that may later be touched arerinsed with large quantities of water. Even one drop of HF onthe skin or fingernail must receive immediate first-ai
23、d andmedical attention should be promptly sought.)12. Interferences12.1 Any bismuth present will appear in the tantalumfraction, but this element is seldom present greater than0.005 % in this ferroalloy. Trivalent antimony, if present, iseluted with the titanium and precipitated with cupferron, but
24、itdoes not interfere in the photometric test method for titanium.13. Apparatus13.1 Ion-Exchange ColumnsThe columns must be con-structed of polystyrene tubing approximately 300-mm long and25 mm in inside diameter. A suitable column can be preparedas follows: Insert a waxed, No. 5 rubber stopper conta
25、ining a5-mm hole into the bottom of the polystyrene tube. Insert intothe hole and flush with the upper surface of the stopper a150-mm length of polystyrene tubing, having a 5-mm outsidediameter and a 2-mm bore. Attach another 150-mm length ofthis tubing to the smaller tube with an approximately 50-m
26、mlength of polyvinyl tubing,4and control the flow rate by ahosecock on the polyvinyl tubing.13.1.1 If a number of determinations are to be made, it isconvenient to arrange the columns so that they can be operatedwith a minimum of attention. Plastic columns equipped withfittings of polystyrene have b
27、een developed for such anassembly.5Inlet and outlet tubes are polyethylene; flexibleconnections, where necessary, are of polyvinyl tubing. Theflow rate is controlled by hosecocks on these flexible connec-tions. The system must be carefully assembled and checked toavoid possible leakage of the soluti
28、ons containing HF.13.2 Plastic WarePolyethylene, polypropylene, or TFE-fluorocarbon.13.2.1 Bottles, 250-mL and 1-L capacity.13.2.2 Graduated Cylinders, 50-mL and 250-mL capacity.13.2.3 Griffn-Form Beakers and Covers, 250-mL, 600-mL,and 1-L capacity.14. Reagents14.1 Ammonium Chloride Solution (240 g/
29、L)issolve 480g of ammonium chloride (NH4Cl) in 1600 mL of water bywarming, cool, dilute to 2 L, and mix. Filter, if necessary. Usethis stock solution to prepare the solutions described in14.2-14.4.14.2 Ammonium Chloride-Ammonium Fluoride NeutralMixtureTransfer 600 mL of the NH4Cl solution and 40 mLo
30、f HF to a plastic beaker. Adjust the pH from 5 to 6 with4Tygon-R tubing has been found satisfactory for this purpose.5Columns available from Ledoux and Co., Inc., Teaneck, NJ, have been foundsatisfactory for this purpose.E367 092NH4OH (approximately 80 mL to 85 mL will be required),dilute to 1 L wit
31、h water, and mix.NOTE 1This solution must be prepared with care. If the pH is too low,the volume specified will not completely elute the tantalum; if the pH istoo high, tantalum will precipitate in the column, thus leading to error inthe determinations being run as well as the one which follows.14.3
32、 Ammonium Chloride-Hydrochloric-Hydrofluoric AcidMixtureTransfer 240 mL of the NH4Cl solution, 200 mL ofHF and 150 mL of HCl to a plastic bottle. Dilute to 1 L withwater, and mix.14.4 Ammonium Chloride-Hydrofluoric Acid MixtureTransfer 600 mL of the NH4Cl solution and 40 mL of HF to aplastic bottle.
33、 Dilute to 1 L with water, and mix.14.5 Ammonium Nitrate Wash Solution (20 g/L)Dissolve20 g of ammonium nitrate (NH4NO3) in water, and dilute to 1L.14.6 Boric Acid (H3BO3).14.7 Cupferron Solution (60 g/L)Dissolve6gofcupfer-ron in 80 mL of cold water, dilute to 100 mL, and filter. Thissolution should
34、 be prepared fresh as needed and cooled to 5 Cbefore use.14.8 Cupferron Wash SolutionAdd 25 mL of cupferronsolution (14.7) to 975 mLof cold HCl (1 + 9), and mix. Prepareas needed.14.9 Hydrochloric-Hydrofluoric Acid MixtureAdd 250mL of HCl to 300 mL of water, add 200 mL of HF, dilute to 1L with water
35、, and mix.14.10 Hydrogen Peroxide (H2O2), 30 %.14.11 Ion-Exchange ResinStrongly basic anion-exchangeresin, 200 mesh to 400 mesh, 8 % to 10 % divinyl-benzenecross linkage.6Since the mesh size of the resin may varyconsiderably from lot to lot, air-dry the resin and pass itthrough a No. 270 (53-m) siev
36、e (Note 2). Most of the fines areremoved from the fraction passing the No. 270 sieve asfollows: Prepare a suspension of the resin in HCl (1 + 9).Allow the coarser fraction to settle 10 min to 15 min andremove the fines by decantation. Repeat the process severaltimes until most of the very fine mater
37、ial has been removedfrom the suspension.NOTE 2Material retained on the No. 270 sieve may be used for otherpurposes.14.12 Oxalate-Citrate-Sulfuric Acid SolutionDissolve 35g of ammonium oxalate (NH4)2C2O4H2O) and 35 g ofdiammonium hydrogen citrate (NH4)2HC8H5O7)in1LofH2SO4(1 + 39).14.13 Pyrogallol (C6
38、H3-1,2,3-(OH)3).14.14 Sodium Hydroxide Solution (100 g/L)Dissolve 20g of sodium hydroxide (NaOH) in 150 mLof water, cool, diluteto 200 mL, and mix. Store in a plastic bottle.14.15 Tantalum, Standard Solution (1 mL = 0.500 mgTa)Transfer 0.1221 g of tantalum pentoxide (Ta2O5)toaplatinum crucible. Add
39、2.5 g of potassium hydrogen sulfate(KHSO4) and heat to fuse the oxide. Dissolve the cooled meltin warm oxalate-citrate-sulfuric acid solution. Transfer to a200-mL volumetric flask, cool, dilute to volume with oxalate-citrate-sulfuric acid solution and mix.14.16 Titanium, Standard Solution (1 mL = 0.
40、100 mg Ti)Transfer 0.0834 g of titanium dioxide (TiO2) to a platinumcrucible. Add1gofKHSO4, and heat to fuse the oxide. Cool,and dissolve the melt in 50 mL of warm H2SO4(1 + 9). Cool,transfer to a 500-mL volumetric flask, dilute to volume withH2SO4(1 + 9), and mix.14.17 Zirconium Solution (1 mL = 1
41、mg Zr)Dissolve 0.5g of zirconium metal in 10 mL of HF in a plastic bottle, anddilute to 500 mL. An equivalent amount of zirconyl chloridemay be substituted for the zirconium metal.15. Preparation of Ion-Exchange Column15.1 Place a 6-mm to 10-mm layer of acid-resistant poly-(vinyl chloride) plastic f
42、iber in the bottom of the column. Addthe resin suspension in small portions to obtain a settled bed ofthe resin 150-mm to 180-mm high. Wash the column withapproximately 100 mL of HNO3(1 + 9), and then performthree elution cycles with alternate additions of 100 mL of HCl(1 + 9) and 100 mL of HCl (3 +
43、 1) to remove the remainder ofthe fines. Finally, wash the column with 200 mL of HCl (1 + 3)to a level about 20 mm above the resin.NOTE 3Resin columns prepared in this way have been used forseveral years; the only maintenance may be to empty and refill the columnwith the resin charge if the flow rat
44、e becomes excessively slow due topacking.16. Preparation of Test Solutions16.1 Transfer a 0.5-g sample, weighed to the nearest 0.1 mg,to a 250-mL plastic beaker. Add 40 mL of the HCl-HF acidmixture. Place a plastic cover on the beaker, and heat gently.After the reaction ceases, add HNO3dropwise unti
45、l thesolution clears (Note 4). Digest on the steam bath for 20 min to30 min to remove nitrous oxide fumes. Rinse the plastic coverand wall of the beaker with the HCl-HF acid mixture, anddilute the solution to 70 mL with the same acid mixture.NOTE 4The addition of HNO3should be kept to a minimum beca
46、useof its strong replacing power for niobium on the exchange column.Approximately 6 drops to 8 drops will be required.16.2 Transfer 50 mL of HCl-HF acid mixture to the columnin 5-mL to 10-mL increments. Drain the acid to a level 100 mmabove the resin bed, collecting the eluate in a 600-mL plasticbea
47、ker. Transfer the sample solution in 5-mL to 10-mLincrements to the column. As the sample solution moves downthe column, continue to add the small increments until all ofthe solution has been transferred. Wash the beaker four or fivetimes with 4-mL portions of the HCl-HF acid mixture, trans-ferring
48、the washings to the column. Wash the sides of thecolumn with 10 mL to 15 mL of the HCl-HF acid mixturefollowed by several washings with the NH4Cl-HCl-HF acidmixture.16.3 Pass a total of 300 mL of the NH4Cl-HCl-HF acidmixture through the column at a flow rate of approximately 100mL/h to 125 mL/h. All
49、ow the solution to drain to the top of theresin. Remove the beaker containing the first fraction andreserve this solution for the determination of titanium. Replacethe beaker with another 600-mL plastic beaker.6Dowex I anion-exchange resin has been found satisfactory. Comparable resultsmay not be obtained with other resins.E367 09316.4 Wash the sides of the column with four or five portions(a total of about 25 mL) of the NH4Cl-HF acid mixture,allowing the solution to drain to the top of the resin each time.Pass a total of 300 mL of the NH4Cl-HF a
