1、Designation: D717 86 (Reapproved 2014)Standard Test Methods forAnalysis of Magnesium Silicate Pigment1This standard is issued under the fixed designation D717; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. 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 analysis of magnesiumsilicate pigment.1.2 The values stated in SI units are to be regarded as thesta
3、ndard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address the safetyconcerns associated with its use. It is the responsibility of theuser of this standard to establish appropriate safety and healthpractices and determine the applicability of regulat
4、ory limita-tions prior to use.2. Referenced Documents2.1 ASTM Standards:2D234 Specification for Raw Linseed Oil (Withdrawn 2007)3D280 Test Methods for Hygroscopic Moisture (and OtherMatter Volatile Under the Test Conditions) in PigmentsD718 Test Methods for Analysis of Aluminum SilicatePigmentD1193
5、Specification for Reagent WaterD1208 Test Methods for Common Properties of CertainPigmentsD2448 Test Method for Water-Soluble Salts in Pigments byMeasuring the Specific Resistance of the Leachate of thePigmentE97 Method of Test for Directional Reflectance Factor,45-Deg 0-Deg, of Opaque Specimens by
6、Broad-BandFilter Reflectometry (Withdrawn 1991)33. Significance and Use3.1 These test methods may be used to confirm the statedSiO2, CaO, and MgO content of magnesium silicate for qualitycontrol.4. Apparatus4.1 Platinum Crucible.4.2 Electric Furnace, capable of 1200C.5. Purity of Reagents5.1 Reagent
7、 grade chemicals shall be used in all tests.Unless otherwise indicated, it is intended that all reagents shallconform to the specifications of the Committee on AnalyticalReagents of the American Chemical Society, where suchspecifications are available.4Other grades may be used, pro-vided it is first
8、 ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination.5.2 Unless otherwise indicated, references to water shall beunderstood to mean Type II of Specification D1193.SILICON DIOXIDE6. Reagents6.1 Hydrochloric Acid (sp gr 1.19)C
9、oncentrated hydro-chloric acid (HCl).6.2 Hydrochloric Acid (1+20)Mix 1 volume of concen-trated hydrochloric acid (HCl, sp gr 1.19) with 20 volumes ofwater.6.3 Hydrofluoric Acid (48 %)Concentrated hydrofluoricacid (HF).6.4 Sodium Carbonate (Na2CO3).6.5 Sulfuric Acid (sp gr 1.84Concentrated sulfuric a
10、cid(H2SO4).7. Procedure7.1 Transfer1gofthesample weighed to 0.1 mg to aplatinum crucible and fuse with5gofNa2CO3until the entirecontents of the crucible are in a molten state. Continue heatingfor 20 min. Keep a close-fitting platinum cover on the crucible1These test methods are under the jurisdictio
11、n of ASTM Committee D01 onPaint and Related Coatings, Materials, and Applications and are the directresponsibility of Subcommittee D01.31 on Pigment Specifications.Current edition approved Dec. 1, 2014. Published December 2014. Originallyapproved in 1943. Last previous edition approved in 2008 as D7
12、17 86 (2008).DOI: 10.1520/D0717-86R14.2For 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.3The last approved vers
13、ion of this historical standard is referenced onwww.astm.org.4Reagent 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, BD
14、H Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1during the fusion. When the fusion is comp
15、lete, allow thecrucible and contents to cool, and transfer to a 600-mLporcelain casserole containing 200 mL of water (Note 1). Boiluntil the melt is disintegrated.NOTE 1If, during the cooling period, the crucible is partially im-mersed several times in cold water to chill the outer portions of the m
16、elt,the subsequent removal of the melt is facilitated. Do not allow the waterto enter the crucible while the contents are hot to avoid spattering.7.2 Remove crucible and lid, being careful to scrub andrinse out any adhering particles of the melt. Carefully acidifythe contents of the casserole with c
17、oncentrated HCl (sp gr1.19); introduce the HCl in small portions, keeping a watchglass over the crucible to avoid loss by spattering. Add 30 mLof HCl in excess and evaporate to dryness on a steam bath; takecare to break up any crusts that form. When the materialappears completely dry, and no odor of
18、 HCl can be detected,remove the casserole from the steam bath, and allow to cool.7.3 Wash down the sides of the casserole with 20 mL of HCl(sp gr 1.19) and then with water. Repeat the evaporation asdescribed in 7.2, then bake for1hinanoven at 105C. Coolthe residue, drench with 25 mL of HCl (sp gr 1.
19、19), add 175mL of water, and warm, while stirring, until all soluble salts aredissolved. Filter off the silica on a close-texture paper, washfive times with HCl (1+20), wash five times with hot water, andreserve the filtrate for determination of other oxides (Section9).7.4 Transfer the paper and was
20、hed silica to a clean platinumcrucible, ignite, first gently until the filter paper is consumed,and then at 1200C for 20 min, cool, and weigh. Moisten theresidue with water, add 5 drops of H2SO4(sp gr 1.84), and 15mL of HF. Evaporate to dryness on a steam bath, heat gentlyuntil H2SO4has been expelle
21、d, and ignite at 1200C for 5 min.Cool and weigh. The loss in weight represents the SiO2.8. Calculation8.1 Calculate the percent of silica as follows:SiO2,%5 P/S! 3100 (1)where:P = SiO2,g,andS = sample used, g.AMMONIUM HYDROXIDE GROUP(Alumina and Iron Oxide)9. Reagents9.1 Ammonium Chloride Solution (
22、2 g/100 mL)Dissolve 2g of ammonium chloride (NH4Cl) in 100 mL of water.9.2 Ammonium Hydroxide (sp gr 0.90)Concentrated am-monium hydroxide (NH4OH).9.3 Hydrochloric Acid (1+3)Mix 1 volume of concen-trated HCl (sp gr 1.19) with 3 volumes of water.9.4 Methyl Red Indicator SolutionDissolve 0.2 g ofmethy
23、l red in 100 mL of methanol, ethanol, or isopropanol.9.5 Potassium Pyrosulfate(K2S2O7).10. Procedure10.1 If an appreciable residue remains after the treatmentwith HF in accordance with 7.4, fuse the residue with a smallamount of K2S2O7until it is dissolved. Leach the pyrosulfatemelt out of the cruci
24、ble with water and combine the solutionwith the filtrate reserved in accordance with 7.3.10.2 Using the methyl red indicator solution, neutralize thecombined solutions from the silica determination with NH4OHand add an excess of 2 drops. Bring to a boil adding NH4OH1 drop at a time if necessary to m
25、aintain a slight alkalinity.Allow the precipitate to settle (not more than 5 min) and filter.Wash four times with hot NH4Cl solution.10.3 Set aside the filtrate and transfer the precipitate andfilter paper to the same beaker in which the first precipitationwas effected. Dissolve the precipitate with
26、 40 mL of hot HCl(1+3), dilute the solution to about 100 mL, and reprecipitate thehydroxides as described in 10.2. Filter and wash the precipitatefour times with hot NH4Cl. Combine the filtrate and washingswith the filtrate set aside and reserve for the determination ofCaO (Section 10).10.4 Place th
27、e precipitate in a weighed platinum crucible,heat slowly until the papers are charred, and finally ignite toconstant weight at 1050 to 1100C with care to preventreduction. Cool and weigh as R2O3(aluminum and ironoxides).11. Calculation11.1 Calculate the percent of R2O3as follows:R2O3,%5 P2/S! 3100 (
28、2)where:P2=R2O3,g,andS = sample used, g.CALCIUM OXIDE12. Reagents12.1 Ammonium Hydroxide (1+1)Mix 1 volume of con-centrated NH4OH (sp gr 0.90) with 1 volume of water.12.2 Ammonium Oxalate Solution(NH4)2C2O4H2O),saturated.12.3 Ammonium Oxalate Solution (1 g/L)Dilute 1.0 g ofammonium oxalate (NH4)2C2O
29、4H2O) in 1 L of water.12.4 Hydrochloric Acid (1+3)See 9.3.12.5 Hydrochloric Acid (1+1)Mix 1 volume of concen-trated hydrochloric acid (HCl, sp gr 1.19) with 1 volume ofwater.12.6 Methyl Red Indicator SolutionSee 9.4.13. Procedure13.1 Acidify the combined filtrates obtained in the precipi-tations of
30、the ammonium hydroxide group (Section 10) withHCl and evaporate them to a volume of about 300 mL. Add 5mL of HCl (1+1), a few drops of methyl red indicator solution,and 30 mL of warm ammonium oxalate solution (saturated).D717 86 (2014)2Heat the solution to 70 to 80C and add NH4OH (1+1)dropwise while
31、 stirring, until the color changes from red toyellow. Allow the solution to stand without further heating for1 h (no longer) with occasional stirring during the first 30 min.Filter and wash moderately with cold dilute ammonium oxalatesolution. Reserve the filtrate and washings.13.2 Transfer the prec
32、ipitate and filter paper to the beaker inwhich the precipitate was effected. Dissolve the oxalate in 40mL of hot HCl (1+3) and macerate the filter paper. Dilute to200 mL with water, add a few drops of methyl red indicatorsolution and 5 mL of ammonium oxalate solution (saturated).Heat the solution ne
33、arly to boiling, and precipitate calciumoxalate again by neutralizing the acid solution with NH4OH asdescribed in 13.1.Allow the solution to stand 1 to 2 h and washas before. Combine the filtrate with that already obtained andreserve for the determination of MgO (Section 16).13.3 Dry the precipitate
34、 in a weighed covered platinumcrucible. Char the paper without inflaming, burn the carbon atas low a temperature as possible, and, finally, heat with thecrucible tightly covered in an electric furnace or over a blastlamp at a temperature of 1100 to 1200C. Cool in a desiccatorand weigh as CaO. Repeat
35、 the ignition to a constant weight.14. Calculation14.1 Calculate the percent of CaO as follows:CaO, % 5P3/S!3100 (3)where:P3= CaO, g, andS = sample used, g.MAGNESIUM OXIDE15. Reagents15.1 Ammonium Hydroxide (sp gr 0.90)Concentrated am-monium hydroxide (NH4OH).15.2 Ammonium Hydroxide (5+95)Mix 5 volu
36、mes ofconcentrated NH4OH (sp gr 0.90) with 95 volumes of water.15.3 Diammonium Phosphate Solution (250 g/L)Dissolve250 g of diammonium phosphate (NH4)2HPO4in enough waterto yield 1 L of solution.15.4 Hydrochloric Acid (1+3)See 9.3.16. Procedure16.1 Acidify the filtrates reserved in the determination
37、 ofCaO (Section 13) with HCl and concentrate to about 400 mL.Add to this solution about 50 mL of (NH4)2HPO4(250 g/L)and if the solution becomes alkaline, add HCl (1+3) to keep thesolution acidic. Cool the solution by placing the beaker in acold water trough or in a tray of ice water. After cooling a
38、ddNH4OH drop by drop, while stirring constantly, until thecrystalline magnesium ammonium phosphate begins to form,and then in moderate excess (5 to 10 % of the volume of thesolution), the stirring being continued for several minutes. Setthe solution aside for at least8hinacool atmosphere.16.2 Filter
39、 the solution on a close-texture paper and washwith NH4OH (5+95). Unfold the filter paper and, using hotwater, wash the precipitate into the beaker in which theprecipitation was effected. Rinse the filter paper with hot HCl(1+3) and again with hot water; if necessary add more hot HCl(1+3) to dissolv
40、e the precipitate. Dilute the solution to about250 mL, add 1 mL of (NH4)2HPO4solution, and then addconcentrated NH4OH drop by drop, while stirring constantly,until the precipitate is again formed as described in the NH4OHis in moderate excess. Cool and allow to stand for about 4 h.16.3 Filter the so
41、lution on a close-texture paper and washsix times with NH4OH (5+95). Transfer the precipitatewrapped in the moist paper to a weighed platinum or porcelaincrucible, slowly char the paper without allowing it to ignite andcarefully burn off the carbon over a gradually increasing flamewhich shall never
42、heat the crucible to more than the faintestred. Finally ignite at 1000 to 1100C to constant weight, takingcare to avoid melting the pyrophosphate.17. Calculation17.1 Calculate the percent of MgO to 0.1 as follows:MgO, % 5 P430.3623!/S# 3100 (4)where:P4=Mg2P2O7,g,andS = sample used, g.molecular weigh
43、t0.2 MgOmolecular weightMg2P2O752 340.32222.605 0.3623 (5)17.2 Consider the sum of MgO, CaO, and SiO2as combinedmagnesium and calcium silicate.LOSS ON IGNITION18. Procedure18.1 Determine the loss on ignition in accordance with TestMethods D1208.MOISTURE AND OTHER VOLATILE MATTER19. Procedure19.1 Det
44、ermine the moisture and other volatile matter byTest Methods D280.COARSE PARTICLES(Total Residue Retained on a No. 325 (45-m) Sieve)20. Procedure20.1 Determine the coarse particles in accordance with TestMethods D718, except that the specimen weight should beadjusted to provide appropriate sensitivi
45、ty for the residualweight determination. Any difficulty encountered in wetting-out the specimen can be overcome by prewetting with a 50+50mixture of acetone or alcohol and water.MATTER SOLUBLE IN WATER21. Procedure21.1 Determine the matter soluble in water by Test MethodD2448 or alternatively by Tes
46、t Methods D1208.D717 86 (2014)3COLOR22. Standard Pigment22.1 Standard Extender Pigment.22.2 Standard Zinc Oxide.23. Procedure23.1 Carefully weigh out the proportions of the standardextender pigment and standard zinc oxide mutually agreedupon, and rub up to a fairly stiff paste with a glass muller on
47、 aglass plate or stone slab with raw linseed oil conforming toSpecification D234. Note the volume of the oil required.Prepare a similar paste with the sample, using the same weightof pigment, volume of oil, and number of strokes of the glassmuller as used in the preparation of the paste of the stand
48、ardpigments. Spread the pastes adjacently on a microscope slide,draw a scraper lightly across them so as to present them on aneven plane, and judge the color immediately.24. Dry Brightness24.1 The test sample and reference sample shall be preparedinto suitable smooth, dry, packed surfaces in accorda
49、nce withaccepted practice and tested for reflectance using the greenfilter in accordance with Test Method E97.PRECISION25. Precision and Bias25.1 Data are not available to determine the precision andbias of these test methods. There are no plans at present toobtain such information. The methods have been in use forseveral years and are considered acceptable.26. Keywords26.1 calcium oxide in magnesium silicate; magnesium ox-ide in magnesium silicate; magnesium silicate pigment, analy-sis of; silicon dioxide, analysis ofASTM International takes
