1、Designation: E 1070 00 (Reapproved 2005)Standard Test Method forDetermination of Phosphorus in Iron Ores by PhotometricMethod1This standard is issued under the fixed designation E 1070; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, 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 covers the determination of phospho-rus in iron ores, concentrates, and agglomerates
3、in the concen-tration range from 0.005 to 1.0 % phosphorus.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is there
4、sponsibility 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:2D 1193 Specification for Reagent WaterE50 Practices for Apparatus, Reagents, and Safety P
5、recau-tions for Chemical Analysis of Metals, Ores, and RelatedMaterialsE60 Practice for Molecular Absorption SpectrometricMethods for Chemical Analysis of Metals, Ores, andRelated MaterialsE 135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related MaterialsE 877 Practice for Sam
6、pling and Sample Preparation of IronOres and Related MaterialsE 882 Guide for Accountability and Quality Control in theChemical Analysis Laboratory3. Terminology3.1 DefinitionsFor definitions of terms used in this testmethod, refer to Terminology E 135.4. Summary of Test Method4.1 The sample is fuse
7、d in a zirconium crucible with sodiumperoxide. The melt is dissolved in water and hydrochloric acid.In a suitable aliquot, the molybdenum blue complex is formedby the addition of ammonium molybdate-hydrazine sulfatesolution. The absorbance of the phospho-molybdenum-bluecomplex is measured at 725 nm.
8、5. Significance and Use5.1 This test method for the analysis of iron ore concentratesand agglomerates is primarily intended as a referee method totest for compliance with compositional specifications. It isassumed that users of this test method will be trained analystscapable of performing common la
9、boratory procedures skill-fully and safely. It is expected that work will be performed ina properly-equipped laboratory and that proper waste disposalprocedures will be followed. Appropriate quality control prac-tices shall be followed, such as those described in Guide E 882.5.2 The determination of
10、 this element is needed for inter-national trade and primary iron and steel making.6. Interferences6.1 Elements normally found in iron ores do not interfereexcepting arsenic giving positive interference (0.01 %As = 0.001 % P).1This test method is under the jurisdiction of ASTM Committee E01 onAnalyt
11、ical Chemistry for Metals, Ores, and Related Materials and is the directresponsibility of Subcommittee E01.02 on Ores, Concentrates, and Related Metal-lurgical Materials.Current edition approved Oct. 1, 2005. Published October 2005. Originallyapproved in 1985. Last previous edition approved in 2000
12、as E 1070 00.2For 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.1Copyright ASTM International, 100 Barr Harbor D
13、rive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7. Apparatus7.1 Zirconium Crucible, 50 mL capacity.7.2 SpectrophotometerVisible spectrophotometer capableof measuring absorbance at the 725 nm wavelength using a1-cm path length cell in accordance with Practice E60.8. Reagents and Ma
14、terials8.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society, wheresuch specifications are available.3Other grades may
15、be used,provided it is first ascertained that the reagent is of sufficienthigh purity to permit its use without lessening the accuracy ofthe determination.8.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water as definedby Type II of Specification
16、 D 1193.8.3 Ammonium Molybdate Solution (20 g/L)To 500 mL ofwater, add cautiously and slowly 300 mL of H2SO4and cool.Add 20 g of ammonium molybdate (NH4)6-Mo7O244H2O. Stirto dissolve and dilute to 1 L with water.8.4 Fusion BlankDissolve4gofNa2O2in 40 mLof waterin a 250-mL beaker. Add 30 mL of HCl. B
17、oil for 2 min. Cooland dilute to 100 mL with water in a volumetric flask. Preparefresh as needed.8.5 Hydrazine Sulfate (1.5 g/L)Dissolve 0.15 g of hydra-zine sulfate NH2NH2H2SO4in water and dilute to 100 mLwith water. Prepare fresh as needed.8.6 Molybdate (5 g/L) Hydrazine Sulfate (0.15 g/L)Solution
18、Add 50 mL of ammonium molybdate solution (20g/L) to 100 mL of water. Add 20 mL of hydrazine sulfatesolution (1.5 g/L) and dilute to 200 mL with water.NOTE 1This solution should be prepared freshly within 30 min of usein a quantity appropriate for the number of tests being made.8.7 Sodium Peroxide (N
19、a2O2)Use caution when usingperoxide.8.8 Sodium Sulfite Solution (100 g/L)Dissolve 10 g ofsodium sulfite (Na2SO3) in water and dilute to 100 mL withwater.8.9 Standard Phosphorus SolutionDry anhydrous diso-dium phosphate (Na2HPO4) at 105C for 2 h and afterdesiccation, dissolve 0.2292 g of the reagent
20、in 200 mL ofwater. Dilute to 1 L with water in a volumetric flask and mix.This solution, A, provides 1 mL = 50 g P. Transfer 10.00 mLof solutionAinto a 50-mLvolumetric flask, dilute to mark withwater, and mix. This solution, B, provides the standardphosphorus solution for calibration 1 mL = 10 g P.9
21、. Hazards9.1 For precautions to be observed in this method, refer toPractices E 50.10. Sampling and Sample Preparation10.1 Collect and prepare gross samples in accordance withPractice E 877.10.2 Pulverize the laboratory sample to pass a No. 100(150-m) sieve.NOTE 2To facilitate decomposition, some or
22、es, such as specularhematite, require grinding to pass a No. 200 (75-m) sieve.11. Calibration and Standardization11.1 The recommended concentration range is from 0.005to 0.10 mg phosphorus in 50 mL of color solution using celldepth of 1 cm.11.2 Into a series of five 150-mL beakers, transfer 10.0 mLo
23、f fusion blank solution (8.4) and then transfer 0, 0.50, 2.50mL of standard B; 1.00 and 2.00 mL of standard A phosphorussolution (8.9) corresponding to 0, 5, 25, 50, and 100 g ofphosphorus respectively. To each beaker add 15 mL of sodiumsulfite solution (8.8). Mix. Bring to a boil. Add 20 mL ofmolyb
24、date-hydrazine sulfate solution (8.6). Bring to a boil.Simmer for 10 min in boiling water bath. Cool. Transfer into a50-mL volumetric flask and dilute to the mark with water. Mix.This solution is stable for at least 2 h.11.3 PhotometryAdjust the spectrophotometer to the ini-tial setting, using water
25、 as the reference solution. Whilemaintaining this setting, measure absorbance of the calibrationstandard and sample solutions at approximately 725 nm in a1-cm cell.11.4 Preparation of Calibration CurveSubtract the absor-bance of the 0-mL phosphorus standard solution from theabsorbance of each standa
26、rd solution and plot the net absor-bance againstgofphosphorus in the color solution.12. Procedure12.1 Weigh approximately the amount of the preparedsample specified in the following table into a small weighingbottle previously dried at 150C:3Reagent Chemicals, American Chemical Society Specification
27、s, AmericanChemical 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, In
28、c. (USPC), Rockville,MD.E 1070 00 (2005)2P Content, %Weight ofSample, gSampleAliquot, mLFusionBlank, mL0.005 to 0.15 0.300 10.0 None0.15 to 0.50 0.100 10.0 None0.50 to 1.0 0.100 5.0 5.0Dry the contents for1hat105to110C. Cap the bottle andcool to room temperature in a desiccator. Momentarily releaset
29、he cap to equalize the pressure and weigh the capped bottleand test sample to the nearest 0.1 mg. Repeat the drying andweighing until there is no further weight loss. Transfer the testsample into a zirconium crucible and reweigh the capped bottleto the nearest 0.1 mg. The difference between the two
30、weightsis the weight of test sample taken for analysis. Add2gofsodium peroxide to the crucible and mix with a dry, stainlesssteel spatula.12.2 Fuse over a burner, swirling the crucible until the meltis cherry red and clear. Remove from the heat and swirl untilthe melt solidifies on the wall of the c
31、rucible.12.3 Place the crucible in a 250-mL dry beaker and cool.Cover with a watch glass and add about 10 mL of water to thecrucible. After the reaction ceases, transfer the crucible con-tents into the beaker, and wash the crucible with water. Add 15mL of HCl to the crucible and transfer to the beak
32、er. Rinse thecrucible with water and add the rinsings to the beaker. Boil for2 min. Cool. Transfer the contents and rinsings into a 50-mLvolumetric flask. Dilute to volume with water and mix.12.4 Transfer appropriate aliquot of the test solution andfusion blank aliquot (in accordance with 11.2) in a
33、 150-mLbeaker. Add 15 mL of sodium sulfite solution (100 g/L). Mix.Bring to a boil. Add 20 mL of molybdate (5 g/L) hydrazinesulfate solution (0.15 g/L). Bring to a boil. Simmer for 10 minin a boiling water bath. Cool. Transfer into a 50-mL volumetricflask and dilute to the mark with water. Mix.12.5
34、Measure absorbance at approximately 725 nm in a1-cm cell in the same manner as the calibration standards.13. Calculation13.1 Subtract the absorbance of the 0-mL phosphorus stan-dard from the absorbance of the test sample solutions. Deter-mine g phosphorus referring to the calibration curve.13.2 Calc
35、ulate the percentage of phosphorus as follows:Phosphorus, % 5 A 3 0.005/B 3 C! (1)where:A = g of phosphorus determined,B = sample aliquot in millilitres (12.1), andC = sample weight in grams (12.1).14. Precision and Bias414.1 PrecisionTable 1 indicates the precision of the testmethod between laborat
36、ories and comparison with the certifiedreference materials.14.2 BiasThe results obtained by the 8 laboratories on thecertified reference iron ores, of varying composition, agreeclosely within narrow limits with the assigned certified phos-phorus values, thus demonstrating absence of any measurablebi
37、as.15. Keywords15.1 agglomerates and related materials; concentrates; ironores; phosphorus content4Supporting data are available from ASTM International Headquarters. RequestRR: E161009.TABLE 1 Statistical InformationSampleAverage Phosphorus Concentration,%Standard DeviationARelativeStandardDeviatio
38、n,B%Number ofParticipatingLaboratoriesNumber ofReplicatesJapan 830-1 (0.125)C0.1270 0.0035 2.75 8 24NBS 690 (0.011)C0.0085 0.0010 11.76 8 24NBS 692 (0.039)C0.0393 0.0022 5.61 8 24NBS 693 (0.056)C0.0554 0.0020 3.61 8 24AStandard deviation.BRelative standard deviations in this test method are calculat
39、ed respectively as follows:s5d2n 2 1!v 5S100xDd2n 2 1!where:x = average concentration, %,d = difference of the determination from the mean, andn = number of determinations.CCertificate valuePhosphorus concentration, %.E 1070 00 (2005)3ASTM International takes no position respecting the validity of a
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42、r 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 copy
43、righted 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).E 1070 00 (2005)4
