1、Designation: C323 56 (Reapproved 2011)Standard Test Methods forChemical Analysis of Ceramic Whiteware Clays1This standard is issued under the fixed designation C323; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、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 These test methods cover the chemical analysis of claysused in the manufacture of ceramic whitewares.1.2 The analytical pro
3、cedures appear in the following order:SectionMoisture 7Loss on Ignition 8Silica 9Iron, Aluminum, and Titanium Oxides 10Iron Oxide 11Titania 12Alumina 13Lime 14Magnesia 15Alkalies 16NOTE 1These test methods have been compiled as standard proce-dures for use in referee analyses. These test methods, ho
4、wever, when thedetermination of iron oxide as Fe2O3is involved, are not intended topreclude the use of other procedures that give results within the permis-sible variations. For the sake of uniformity the classical Zimmerman-Reinhardt procedure is specified for the determination of iron oxide. It is
5、recognized that numerous other procedures are equally accurate and oftenmore convenient. The other procedures commonly in use include reduc-tion of an oxidized solution with zinc or other metal, and titration withstandard potassium permanganate (KMnO4) or potassium dichromate(K2Cr2O7) solution, as w
6、ell as titration with a standard solution of titanouschloride in an oxidized solution. These procedures shall be consideredacceptable, provided the analyst has obtained results by his specialprocedure that check with the Zimmerman-Reinhardt procedure within thelimits specified in Section 17. It is s
7、uggested that National Institute ofStandards and Technology standard samples be used for checking theaccuracy of procedures.It will be understood that the making of a complete analysis of aceramic whiteware clay is a difficult procedure requiring a wide knowl-edge of the chemistry involved in the op
8、erations and a thorough trainingin carrying out the work. A skilled analyst of good training is thereforerequired to do the work. The descriptions here given cover the vital pointsof procedure, but frequent reference in regard to the details of the variousmanipulations should be made to “Applied Ino
9、rganic Analysis” byHillebrand and Lundell2and to similar publications. Particularly in thedetermination of alumina, reference should be made to Scientific PaperNo. 286 of the National Bureau of Standards.31.3 The values stated in acceptable metric units are to beregarded as the standard. The values
10、given in parentheses arefor information only.1.4 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 establish appro-priate safety and health practices and determine the applica-bility of regula
11、tory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:4C322 Practice for Sampling Ceramic Whiteware ClaysE11 Specification for Woven Wire Test Sieve Cloth and TestSieves3. Reagents3.1 Unless otherwise indicated, it is intended that all re-agents shall conform to the specifications
12、of the Committee onAnalytical Reagents of the American Chemical Society, wheresuch specifications are available.5Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination. Unless other
13、wise indicated, references towater shall be understood to mean distilled water. Paragraphs3.1.1-3.1.16 include those reagents common to two or more ofthe analytical procedures. Other reagents will be found listedwith the particular test method in which they are prescribed.3.1.1 Concentrated Acids an
14、d Ammonium HydroxideConcentrated acids and ammonium hydroxide of approxi-mately the following specific gravities or concentrations willbe required:1These test methods are under the jurisdiction of ASTM Committee C21 onCeramic Whitewares and Related Products and are the direct responsibility ofSubcom
15、mittee C21.04 on Raw Materials.Current edition approved March 1, 2011. Published March 2011. Originallyapproved in 1956. Last previous edition approved in 2006 as C323 - 56 (2006).DOI: 10.1520/C0323-56R11.2Hillebrand, W. F., and Lundell, G. E. F., Applied Inorganic Analysis, Wiley andSon, New York,
16、1929.3Blum, W., “Determination of Alumina as Oxide,” National Bureau of Stan-dards, Scientific Paper No. 286.4For 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 sta
17、ndards Document Summary page onthe ASTM website.5Reagent Chemicals, American Chemical Society Specifications, 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
18、, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Hydrochloric acid (HCl) 1.19 sp grNitric acid (HNO3) 1
19、.42spgrSulfuric acid (H2SO4) 1.84spgrHydrofluoric acid (HF) 40 %Perchloric acid (HClO4) 60to70%,cpASulfurous acid (H2SO3) 6 % solutionBAmmonium hydroxide (NH4OH) 0.90 sp gr_ALower purity varieties may contain aluminum oxide, (Al2O3), as an impurity.BAs supplied by reagent manufacturers.3.1.2 Diluted
20、 Acids and Ammonium HydroxideThe di-luted acids and ammonium hydroxide referred to are of varyingpercentages by volume. They shall be made up by mixingproportional volumes of the concentrated reagent and water.The diluted sulfuric acid mixtures shall be made up by slowlystirring the acid into the wa
21、ter. These diluted acids andammonium hydroxide are designated in the methods as (1 + 4),(1 + 9), and so forth, except very diluted solutions which arereferred to by the percent of reagent added. The designation inparentheses indicates the ratio of the volume of the concen-trated reagent to the volum
22、e of water; for example, H2SO4(1 + 9) contains 10 volume % of H2SO4(sp gr 1.84). Thefollowing will be required:Volume %HCl 5020H2SO450105HNO3303NH4OH 503.1.3 Ammonium Chloride (2 %)Dissolve2gofNH4Clin 100 mL of water.3.1.4 Ammonium Oxalate Solution (Saturated)Dissolve 4gof(NH4)2C2O in 100 mL of wate
23、r.3.1.5 Chloroplatinic Acid Solution (10 %).3.1.6 Diammonium Phosphate SolutionDissolve 10 g of(NH4)2HPO4in 100 mL of water.3.1.7 Ethyl Alcohol (80 %)Prepare a solution containing80 volume % of ethyl alcohol in water.3.1.8 Ethyl Alcohol (Absolute)Certain commercial brandsof denatured absolute alcoho
24、l are satisfactory as well as beingconsiderably less expensive than the reagent grade absolutealcohol.3.1.9 Hydrogen Peroxide (30 %) (H2O2).3.1.10 Manganese Sulfate SolutionDissolve 70 g of crys-talline MnSO4in 500 mL of water. Add 140 mL of phosphoricacid (H3PO4, sp gr 1.7), and 130 mL of sulfuric
25、acid (H2SO4,sp gr 1.84). Dilute to 1 L.3.1.11 Mercuric Chloride Solution (Saturated)Prepare asaturated solution of HgCl2.3.1.12 Potassium Permanganate, StandardSolution (0.1N)Dissolve 3.25 g of KMnO4in 1000 mL ofwater. Allow to stand for one week, filter through an asbestosmat, porous glass, or porc
26、elain filter, and keep in a dark place.Standardize against the National Institute of Standards andTechnology standard Sample No. 40c of sodium oxalate.3.1.13 Potassium Permanganate, StandardSolution (0.04N)Dissolve 2.5 g of KMnO4in water andmake up to 2 L. Allow to stand for one week, filter through
27、 anasbestos mat, porous glass, or porcelain filter, and keep in adark place. Standardize against the National Institute of Stan-dards and Technology standard Sample No. 40c of sodiumoxalate.3.1.14 Sodium Arsenite, Standard Solution Dissolve0.908 g of arsenious oxide, (As2O3), in a small amount of ho
28、tsodium carbonate (Na2CO3) solution, cool, filter, and dilute to1 L. Standardize against a steel of known manganese content.3.1.15 Stannous Chloride Solution (50 g/L)Dissolve 50 gof SnCl2in 100 mL of HCl and dilute to 1000 mL. Keep a fewpieces of metallic tin in the bottle.3.1.16 Titania, Standard S
29、olutionWeigh out 0.05 g ofcalcined titanium dioxide (TiO2). Fuse with 10 g of K2S2O7ina clean platinum crucible, keeping the temperature as low aspossible to maintain fluidity. Cool, and dissolve in about 300mL of H2SO4(1 + 5). Cool, transfer to a 500-mL volumetricflask, dilute to the mark with wate
30、r, and mix thoroughly. Tostandardize the solution, take two 50-mL portions in 400-mLbeakers, dilute, boil, and precipitate with NH4OH. Filter, andwash with hot water. Place the papers in the original beakers,add 15 mL of HCl, stir to macerate the paper, dilute, andprecipitate again with NH4OH. Filte
31、r, and wash with hot wateruntil free of alkali salts. Ignite carefully, blast, and weigh. Fromthe weight determined, calculate the strength of the solution.4. Sampling4.1 Selection of SampleObtain the sample in accordancewith Practice C322.4.2 Crush the sample in a small jaw or roll-type crusher wit
32、hhardened tool-steel faces to pass a 2.36-mm (No. 8) sieve (Note2). Crush the sample to pass a 850-m (No. 20) sieve, mix, andquarter to about 50 g. Grind this 50-g sample so that it will allpass a 150-m (No. 100) sieve, unless otherwise specified, mixthoroughly, and place in a container that will en
33、sure freedomfrom contamination. Do fine grinding in a suitable mortar(agate, mullite, alumina, or boron carbide) to prevent theintroduction of impurities. Take precautions to prevent con-tamination of the sample by steel particles from the samplingequipment during crushing or grinding.NOTE 2Detailed
34、 requirements for these sieves are given in Specifi-cation E11.5. Method of Analysis5.1 Determine moisture on the sample in its ordinaryair-dried condition. Determine all other percentage composi-tions on moisture-free samples and report accordingly on amoisture-free basis. The drying temperature re
35、commended forall moisture determinations is 105 to 110C. Whenever asample is weighed out for any determination other thanmoisture, it shall be moisture-free. If preferred, the sample maybe dried in a weighing bottle from which the required samplesshall be weighed out.6. Blank Determinations6.1 Make
36、blank determinations on the reagents for eachconstituent in the whiteware clay and deduct this blank in eachcase. For the determination of the silica (SiO2) blank, approxi-mately 0.25 g of Al2O3should be added as aluminum chloride.C323 56 (2011)27. Moisture7.1 Weigh 1.00 g of the sample and heat to
37、constant weightat a temperature not under 105 nor over 110C. Record the lossin weight as moisture.8. Loss on Ignition8.1 Weigh 1.000 g of the moisture-free (105 to 110C)sample and heat to constant weight over a blast lamp, or in anelectric muffle furnace, at 900 to 1000C. Record the loss inweight as
38、 the ignition loss.9. Silica9.1 Weigh 0.5000 g of the moisture-free (105 to 110C)sample into a platinum crucible containing about5gofpowdered anhydrous Na2CO3and mix well with a platinumwire. Cover the mixture with a little more Na2CO3. Heatgradually to the full heat of a good burner (1000 to 1100C)
39、maintained for about 1 h until complete solution is obtained.Place the crucible cover on a triangle, and when the melt haspartially cooled, pour it on the lid (Note 3). When cool, placethe crucible and lid in a 150-mL beaker, placing the button ona watch glass above the beaker. Add 30 mL of HCl (1 +
40、 1).When solution is complete wash off the crucible and lid withHCl (1 + 4), taking care to remove all SiO2. Place the button inthe solution. Transfer the contents of the beaker to an evapo-rating dish and evaporate to dryness on a steam bath. Bake for1 h at 110C.Add 20 to 30 mL of HCl (1 + 1) and 5
41、0 mL of hotwater. When all salts have been dissolved, allow to settle forseveral minutes and then filter through a general-purpose gradeacid-washed medium-retention filter paper. Wash the SiO2three times by decantation using 20- to 30-mL portions of firsthot water, then HCl (1 + 1), then hot water a
42、gain. Transfer theprecipitate to the filter paper, removing all SiO2from the dishwith a policeman. Wash the paper and precipitate with hotwater until free from salt. To recover the small amount of SiO2remaining in the filtrate, evaporate to dryness, using the sameprocedure for baking and filtering a
43、s before. Combine the twoprecipitates, place in a platinum crucible, and burn off thepaper carefully to prevent any loss of SiO2. Ignite the sampleto constant weight at 1100 to 1200C (15 to 20 min is usuallysufficient), cool in a desiccator, and weigh. Moisten the residuewith several millilitres of
44、water, add 10 mL of HF and three orfour drops of H2SO4. Evaporate the solution to dryness, ignitecarefully to prevent decrepitation, and blast for several minutesat 1100C. Cool the crucible in a desiccator, weigh, and repeatblasting to constant weight. The loss in weight from theoriginal silica resi
45、due represents the SiO2content, except forthat part of the SiO2which is later recovered from alumina, andso forth.NOTE 3Another scheme to aid in subsequent solution of the fusedmelt is to rotate the crucible as it cools, spreading the mass up the sidewalls.10. Iron, Aluminum, and Titanium Oxides10.1
46、 Fuse the residue with1goffused potassium pyrosul-fate (K2S2O7) or sodium pyrophosphate (Na2S2O7), dissolve ina small amount of water, and add to the filtrate from the silicadetermination (Section 9).Add5gofNH4Cl and three dropsof 0.1 % methyl red solution. Heat the solution almost toboiling, and ad
47、d slowly NH4OH (1 + 1) until the indicator haschanged to a yellow color. Boil for several minutes to removethe excess ammonia. Allow to settle for 30 min and decantthrough an open, rapid-filtering acid-washed filter paper, trans-ferring the precipitate to the paper and washing the beaker andpaper se
48、veral times with a warm 2 % NH4Cl solution. Reservethe filtrate, “A,” for the determination of calcium oxide (CaO)and magnesium oxide (MgO) (Section 14). Return the precipi-tate and paper to the original beaker, add 50 mL of hot waterand 10 mL of HCl (sp gr 1.19). Stir until the precipitate isdissol
49、ved and the paper is well macerated. Dilute to about 200mL with hot water, precipitate and filter as before. Combinethis filtrate “B” with filtrate “A.” Wash the paper and precipi-tate with a warm 2 % NH4Cl solution. Place the precipitate ina weighed platinum crucible and ignite. Continue the ignitionat 1200C to constant weight (15 to 20 min is usuallysufficient). Cool in a desiccator, and weigh with the cruciblecovered with the lid. The R2O3consists of the aluminum oxide(Al2O3), TiO2, and Fe2O3present in the sample. In addition,there may be sma
