1、Designation: D4481 10Standard Test Method forTotal Nickel in Fresh Alumina-Base Catalysts1This standard is issued under the fixed designation D4481; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A numbe
2、r in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of nickel infresh alumina-base catalysts and has been tested at nickelconcentrations from 2.5 to 6
3、0 weight %, expressed as nickeloxide (NiO).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 theresponsibility of
4、the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to its use.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD7442 Practice for Sample Preparation of Fluid CatalyticCracking
5、 Catalysts and Zeolites for Elemental Analysis byInductively Coupled Plasma Atomic Emission Spectros-copyE105 Practice for Probability Sampling of MaterialsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE456 Terminology Relating to Quality and StatisticsE691 Practice for Co
6、nducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Summary of Test Method3.1 The test specimen (as received) is treated with concen-trated hydrochloric acid to solubilize the nickel. If necessary,nickel is recovered from any insoluble residue by potassiumpyrosulfate fusio
7、n, after hydrofluoric-sulfuric acid treatment toremove silica. Ammonium citrate is added to complex thealuminum and buffer the solution. Nickel is precipitated asnickel dimethylglyoxime, Ni (C4H7O2N2)2, at a weakly alka-line pH. The precipitate is washed and weighed as Ni(C4H7O2N2)2after drying at 1
8、20C.3.2 A separate test specimen is taken to determine loss onignition (LOI) at 550C. The value is used to calculate thenickel as percent nickel oxide (NiO) on a 550C dry basis.4. Significance and Use4.1 This test method sets forth a procedure by whichcatalyst samples can be compared either on an in
9、terlaboratoryor intralaboratory basis. It is anticipated that catalyst producersand users will find this method of value.5. Interferences5.1 Cobalt, molybdenum, and aluminum do not interfere.Interferences by elements that precipitate as hydroxides, suchas iron, chromium, aluminum, lead, tin, mangane
10、se, titanium,and zirconium, are avoided by the addition of ammoniumcitrate before making the solutions ammoniacal. Copper,present in the 2 to 10 % range, tends to be co-precipitated withthe nickel dimethylglyoxime. The only other metal ions pre-cipitated by dimethylglyoxime are palladium, gold, and
11、bis-muth.6. Apparatus6.1 Beakers, 600-mL, 150-mL.6.2 Hotplate.6.3 Furnace, electric muffle. Calibrated and capable ofmaintaining temperatures of 550 6 25C, and 950 6 25C.6.4 Platinum Dishes, 100-mL3capacity.6.5 Mortar and Pestle, agate, or equivalent mechanicalgrinder.6.6 Crucibles, sintered-glass,
12、30-mL, medium porosity frit.6.7 Fiberglass Filter, 3.2 cm.6.8 Drying Oven capable of maintaining a temperature of120C.6.9 Vacuum Filtering Flask, 500-mL.6.10 Filter Holder and Filter Disk, Millipore 0.65 m-47-mm diameter.6.11 pH Paper to detect a value of 9.6.12 Screen, 250-m openings, 60-mesh.6.13
13、Analytical Balance, capable of weighing to nearest 0.1mg.1This test method is under the jurisdiction of Committee D32 on Catalysts andis the direct responsibility of Subcommittee D32.03 on Chemical Composition.Current edition approved April 1, 2010. Published May 2010. Originallyapproved in 1985. La
14、st previous edition approved in 2004 as D448104. DOI:10.1520/D4481-10.2For 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
15、 website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.14 Ashless Filter Pulp.6.15 Desiccator.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall
16、reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.3Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening
17、 theaccuracy of the determination.7.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean type IV reagent water asdefined in Specification D1193.7.3 Ammonium Citrate, dibasic crystal, (NH4)2HC6H5O7.7.4 Ammonium Hydroxide, 10 and 25 % solutions.NOTE 1Refer to Sec
18、tion 8 on Hazards in Practice D7442 for hazardsassociated with handling of acids.7.5 Hydrochloric Acid, concentrated 38 %.7.6 Hydrofluoric Acid, concentrated 48 %.7.7 Methyl Red Indicator (o-carboxy benzeneazodimethylaniline)Dissolve 0.02 g in 60-mL reagent gradeethanol. Add 40.0 mL of distilled wat
19、er.7.8 4A Molecular Sieve, activated for2hat275C.7.9 Potassium Hydrogen Sulfate, fused power-acid-fluxgrade.7.10 Sodium Dimethylglyoxime, 8-Hydrate, crystal,CH3C:NONaC:NONaCH38H2O. Prepare a 1 weight % pervolume solution in water.7.11 Sulfuric Acid, 10 and 50 % solutions.NOTE 2The sodium salt of dim
20、ethylglyoxime is recommended, ratherthan the organic reagent, dimethylglyoxime because the salt is watersoluble. Large excesses added to precipitate the nickel do no harm as theexcess dimethylglyoxime is eliminated during the filtration and washingpart of the procedure. The organic reagent, dimethyl
21、glyoxime, is not verysoluble in water and is often added as a 1 % solution in ethanol. Whenadded in this way, some of the excess reagent may contaminate theprecipitated nickel complex. For this reason an aqueous solution of thesodium salt is preferred. If the alcohol solution of dimethylglyoxime is
22、tobe used, add an amount so that the alcohol content of the sample solutiondoes not exceed 50 % or some of the precipitated nickel dimethylglyoxy-mate may dissolve.8. Sampling8.1 The selection of a representative analytical sample fromthe bulk material is outside the scope of the present testmethod.
23、 It is presumed that parties using this test method forcomparison purposes will have agreed on the selection of ananalytical sample. If a sampling procedure is desired, PracticeE105 is recommended.8.2 Grind the sample to pass through a 60-mesh screen.9. Procedure9.1 Weigh three test specimens suffic
24、ient to yield 50 to 75mg of NiO into 150-mL beakers. Record mass to the nearest0.1 mg as G.9.2 Weigh three 1-g test specimens into platinum dishes orporcelain crucibles. Record mass to the nearest 0.1 mg as G1.Calcine for2hina550C muffle furnace. Transfer to adesiccator containing freshly activated
25、4A molecular sieve.Cool, weigh, record mass as G2, and calculate percent solids.9.3 To test specimens from 9.1, add 20-mL of concentratedhydrochloric acid and heat gently on a hotplate until only apaste of solids is left. Do not boil the solution. Do not bakesolids or subsequent re-solution will be
26、difficult.9.4 Add 20 mL of concentrated hydrochloric acid and warmon a hotplate 15 to 30 min to dissolve salts. Cool and dilute toabout 100 mL with deionized water.9.5 Filter solids on 0.45-m filter, using a 500-mL filterflask as a receiver. Wash the beaker with four approximately20-mL portions of d
27、eionized water, transferring the washes tothe filter. Wash the solids on the filter with three more 20-mLportions of deionized water. Quantitatively transfer the filtrateplus washes to a 600-mL beaker. Keep the beaker covered untilready to precipitate nickel.9.6 Put a filter disk into a platinum dis
28、h and cover withashless filter pulp. Carefully char over a gas burner, then igniteat red heat until the carbon is essentially burned off. Put thedish in a muffle furnace at 960C for 50 min.9.7 To solids in the platinum dish, add 10 mL of 48 %hydrofluoric acid and 5 mL of 10 % sulfuric acid and evapo
29、ratecarefully to dryness on a hotplate. Then, carefully bring to a redheat over a gas burner until the sulfur trioxide fumes cease.Cool and add5gofreagent potassium pyrosulfate and fuseover a gas burner until a clear melt is obtained. Cool, add 10mL of 10 % sulfuric acid, 20 mL of deionized water, a
30、nd heatgently on a hot plate until the melt dissolves.9.8 Filter the solution (9.7) through a 0.45-m filter, using a500-mL filter flask as a receiver. Wash crucibles with fourapproximately 20-mL portions of deionized water. Combinefiltrate with solution in beaker (see 9.5). Wash the filter flaskwith
31、 three approximately 20-mL portions of deionized water,adding washings to beaker.9.9 Add 20 mL of ammonium citrate to solution. Heat to 70to 80C on a steam bath. Add 10 drops of methyl red indicatorsolution and adjust pH to the yellow color by careful additionof 25 % of ammonium hydroxide or 10 % of
32、 sulfuric acid.9.10 Add 60 mL of 1 % dimethylglyoxime solution. Imme-diately add concentrated ammonium hydroxide dropwise untilthe precipitation takes place. Continue dropwise addition untilthe solution reads pH 9 with pH paper. Cover the beaker. Placethe beaker on a steam bath and heat for 30 min t
33、o coagulate theprecipitate. Remove from the steam bath, allow to cool to roomtemperature, and check the pH. If pH is not 9 by pH paper,adjust to that pH.9.11 Allow the precipitate to settle at least 10 h. Test forcomplete precipitation by adjusting pH to 9 if necessary andadding an additional 3 mL o
34、f 1 % dimethylglyoxime solution.If precipitation is incomplete, add an additional 5 mL of 1 %dimethylglyoxime solution and return to steam bath for 30 min.3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagent
35、s notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.D4481 102Allow to cool and check again for completion. If prec
36、ipitationis still incomplete, discard sample. Recheck calculation of thetest specimen size.9.12 Dry and weigh a sintered glass crucible containing a3.2-cm fiberglass filter. Record the weight at G0.NOTE 3The use of a 3.2-cm fiber glass filter facilitates filtering andminimized clogging of the pores
37、of the sintered glass frit of the crucible.This makes it easier to clean crucibles for re-use. Weigh the dry crucibleplus the fiber glass filter prior to the filtration of nickel dimethylglyoxy-mate.9.13 Filter the mixture from 9.11, using a gentle suction,through the crucible and filter as prepared
38、 in 9.12. Wash theprecipitate in the crucible five times with water. Dry thecrucible for2hat120C, allow to cool in a desiccatorcontaining activated 4A molecular sieve and weigh the cru-cible, plus precipitate. Record the weight to nearest 0.1 mg asG3. Return to an oven for 30 min, cool, and weigh ag
39、ain.Repeat until successive weights agree to 0.1 mg.10. Calculations10.1 Calculate the percent solids, B, using the followingequation:B 5G2G13 100 (1)where:G1= weight of test specimen before calcination andG2= weight of calcined test specimen10.2 Calculate the amount of nickel oxide, using the fol-l
40、owing equation:Nickel as % NiO 5G3 G0! 3 2587B 3 G(2)where:G3= weight of crucible with precipitate, expressed tonearest 0.1 mg,G0= weight of crucible plus fiber glass filter, expressed tonearest 0.1 mg,G = weight of the test specimen, andB = percent solids, expressed as number between 0 to100 to two
41、 decimal places.11. Precision and Bias411.1 Test ProgramAn interlaboratory study was con-ducted in which the named property was measured in threeseparate test materials in five separate laboratories. PracticeE691, modified for non-uniform data sets, was followed for thedata reduction. Analysis detai
42、ls are in the research report.11.2 PrecisionPairs of test results obtained by a proce-dure similar to that described in the study are expected to differin absolute value by less than 2.772 S, where 2.772 S is the95 % probability interval limit on the difference between twotest results, and S is the
43、appropriate estimate of standarddeviation. Definitions and usage are given in TerminologyE456 and Practice E177, respectively.95 % Repeatability 95 % ReproducibilityTest Result(Consensus Mean)Interval(Within Laboratory)Interval(Between Laboratories)54.974 weight % 0.543 weight %(0.99 % of mean)2.467
44、 weight %(4.49 % of mean)14.373 weight % 0.272 weight % 1.323 weight %(1.89 % of mean) (9.20 % of mean)2.916 weight % 0.028 weight % 0.065 weight %(0.97 % of mean) (2.24 % of mean)11.3 BiasThe test method described is without knownbias since there are no reference standards available forcomparison.1
45、2. Keywords12.1 alumina-base catalyst; nickelASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, an
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48、ouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted 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 obt
49、ained 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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).4Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D32-1014.D4481 103
