ASTM D5184-2001(2006) Standard Test Methods for Determination of Aluminum and Silicon in Fuel Oils by Ashing Fusion Inductively Coupled Plasma Atomic Emission Spectrometry and Atom.pdf

1、Designation: D 5184 01 (Reapproved 2006)An American National StandardStandard Test Methods forDetermination of Aluminum and Silicon in Fuel Oils byAshing, Fusion, Inductively Coupled Plasma AtomicEmission Spectrometry, and Atomic AbsorptionSpectrometry1This standard is issued under the fixed designa

2、tion D 5184; 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 parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision o

3、r reapproval.1. Scope1.1 These test methods cover the determination of alumi-num and silicon in fuel oils at concentrations between 5 and150 mg/kg for aluminum and 10 and 250 mg/kg for silicon.1.2 Test Method AInductively coupled plasma atomicemission spectrometry is used in this test method to quan

4、tita-tively determine aluminum and silicon.1.3 Test Method BFlame atomic absorption spectrometryis used in this test method to quantitatively determine alumi-num and silicon.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.

5、5 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 regulatory limitations prior to use. Specific warning

6、statements are given in Sections 7.6, 10.1, and 11.5.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reagent WaterD 4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD 4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD 6299 Practice for App

7、lying Statistical Quality AssuranceTechniques to Evaluate Analytical Measurement SystemPerformanceE 135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related Materials3. Terminology3.1 Definition:3.1.1 emission spectroscopyRefer to Terminology E 135.3.2 Definitions of Terms Speci

8、fic to This Standard:3.2.1 calibrationthe process by which the relationshipbetween signal intensity and elemental concentration is deter-mined for a specific element analysis.3.2.2 check standardin calibration, an artifact measuredperiodically, the results of which typically are plotted on acontrol

9、chart to evaluate the measurement process.4. Summary of Test Methods4.1 A weighed quantity of homogenized sample is heated ina clean platinum dish, the combustible material is removed byburning and the carbon finally removed by heating in a mufflefurnace at a temperature of 550 6 25C. The residue is

10、 fusedwith a lithium tetraborate/lithium fluoride flux. The fusedmixture is digested in a solution of tartaric acid and hydrochlo-ric acid and diluted to volume with water. The resultingsolution is aspirated into an inductively-coupled plasma andthe emission intensities of aluminum and silicon lines

11、 aremeasured. Standard calibration solutions are also aspirated andaluminum and silicon intensities are measured for comparison.Alternatively, the resulting solution is aspirated into the flameof an atomic absorption spectrometer and the absorptions of theresonance radiation of aluminum and silicon

12、are measured.Standard calibration solutions are also aspirated and aluminumand silicon absorption intensities are measured for comparison.5. Significance and Use5.1 Catalyst fines in fuel oils can cause abnormal enginewear. These test methods provide a means of determiningsilicon and aluminum, the m

13、ajor constituents of the catalysts.1These test methods are under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and are the direct responsibility of Subcommit-tee D02.03 on Elemental Analysis.Current edition approved May 1, 2006. Published June 2006. Originallyapproved in

14、 1991. Last previous edition approved in 2001 as D 5184 01.2For 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.1C

15、opyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Apparatus6.1 Balance, capable of weighing to 0.1 g, capacity of150 g.6.2 Choice of Instrument:6.2.1 Inductively-Coupled Plasma Atomic EmissionSpectrometerEither a sequential or simulta

16、neous spectrom-eter is suitable, if equipped with an ICP torch and RF generatorto form and sustain the plasma.6.2.2 Atomic Absorption SpectrometerA suitable instru-ment will consist of modulated hollow cathode lamps or othersources of resonance radiation of aluminum and silicon, anitrous oxide/acety

17、lene burner, and a spectrometer with asuitable detection and read-out system.6.3 Homogenizer, non-aerating, high-speed shear mixer tohomogenize the sample.NOTE 1Ultrasonic bath and ultrasonic probe type homogenizers werenot evaluated in the development of these test methods.6.4 Electric Muffle Furna

18、ce, capable of being maintained attemperatures of 550 6 25C and 925 6 25C. The furnacepreferably having suitable apertures at front and rear to allowa slow, natural draft of air to pass through.6.5 Electric Hot Plate, with or without magnetic stirringcapability.6.6 Electric Oven, maintained at a tem

19、perature of 50 to60C.6.7 Graduated Cylinders, 10, 25, 50, and 100 mL.6.8 Pipettes, 1, 2, 5, 10, 20, and 25 mL.6.9 Platinum Dish, 100 mL capacity, cleaned with fusedpotassium hydrogen sulfate.6.10 Volumetric Flasks, 100 and 1000 mL.6.11 All glassware must be carefully cleaned with 1 + 1hydrochloric a

20、cid and rinsed thoroughly with water to mini-mize contamination. The use of chromic acid cleaning solutionis not recommended.6.12 Zirconium crucible with close fitting zirconium lid, 30to 50 mL capacity.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherw

21、ise 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 be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to per

22、mit its use without lessening the accuracy ofthe determination.7.2 Purity of WaterUnless otherwise indicated, referenceto water shall be understood to mean reagent water conformingto Type II of Specification D 1193.7.3 FluxMixture of 90 % lithium tetraborate and 10 %lithium fluoride.NOTE 2Lithium fl

23、uoride is necessary to prevent heavy metal corro-sion of the platinum dish and to lower the fusion temperature.7.4 Hydrochloric acid (36 % (m/m)concentrated hydro-chloric acid.7.5 Potassium Hydrogen Sulfate, fused solid.7.6 2-Propanol (Isopropyl Alcohol) (WarningFlammable; can be explosive when evap

24、orated to or neardryness.)7.7 Aqueous Standard Solutions.7.7.1 Aluminum Standard SolutionsObtain a ready made,aqueous standard or prepare a standard from aluminum wire.7.7.1.1 Aluminum Solution (1000 mg/L)Aqueous, readymade commercial standard.7.7.1.2 Aluminum Solution (1000 mg/L)Cut an arbitrarylen

25、gth of 99.99 % minimum purity aluminum wire (2 mmdiameter aluminum wire has been found satisfactory). Measurethe length to the nearest 0.1 cm and weigh the aluminum wireto the nearest 0.001 g. Determine the mass/cm for the alumi-num wire and cut a length of aluminum wire that is calculatedto be slig

26、htly greater than 1.000 g. Trim off the excess wireuntil the mass is 1.000 6 0.005 g. Dissolve the aluminum wirein 50 mL of concentrated hydrochloric acid. Heat gently. Cooland transfer the solution to 1000 mL volumetric flask. Dilute tothe mark with water.7.7.2 Silicon Standard SolutionsObtain a re

27、ady made,aqueous standard or prepare a standard from silicon dioxide.7.7.2.1 Silicon Solution (1000 mg/L)Aqueous, readymade commercial standard.7.7.2.2 Silicon Solution (1000 mg/L)Using a zirconiumcrucible with a close fitting lid, fuse 2.140 6 0.0107 g ofsilicon dioxide (99.99 % purity) with8gofsod

28、ium hydroxideuntil a clear melt is obtained. Cool and dissolve the melt in100 mLof a solution of 1 part hydrochloric acid by volume and2 parts water by volume. Transfer this solution to a 1000 mLvolumetric flask and dilute to the mark with water. Immedi-ately, transfer the contents of the flask to a

29、 plastic bottle.7.8 Tartaric Acid/Hydrochloric Acid SolutionDissolve 5 gof tartaric acid in about 500 mL of water acidified with 40 mLof concentrated hydrochloric acid and dilute to 1000 mL withwater.7.9 Toluene/2-Propanol Solution (1 + 1)Mix one vol-ume of toluene with one volume of 2-propanol.7.10

30、 Quality Control (QC) Samples, preferably are portionsof one or more liquid petroleum materials that are stable andrepresentative of the samples of interest. These QC samplescan be used to check the validity of the testing process asdescribed in Section 18.8. Quality Control (QC) Sample Preparation8

31、.1 Preparation of QC Samples shall follow the sameprotocol as defined for the test specimen (Sections 9, 10, and11).9. Sampling9.1 The objective of sampling is to obtain a sample fortesting purposes that is representative of the entire quantity.Thus, take samples in accordance with the instructions

32、inPractice D 4057 or D 4177 . Typically, a gallon size containerfilled to approximately three-fourths of capacity is satisfactory.3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the Americ

33、an Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.D 5184 01 (2006)210. Sample Handling10.1 HomogenizationIt is extremely important to hom

34、og-enize the fuel oil in the sample container in order to obtain arepresentative specimen. (WarningFailure to use this ho-mogenization procedure can invalidate the results becausenon-representative aliquots could be obtained and this couldlead to erroneous results.)10.2 Place the sample container in

35、 an oven at a temperatureof 50 to 60C. Keep the container in the oven until the samplecomes to temperature. Insert the shaft of a high speed homog-enizer into the sample container so that the head of the shaft isimmersed to approximately 5 mm from the bottom of thesample vessel. Mix the sample for a

36、bout 5 min.11. Specimen Preparation11.1 Weigh a clean platinum dish to the nearest 0.1 g.Immediately transfer up to 50 g (but not less than 20 g) of thewell-mixed sample, preferably containing about 1.3 mg alumi-num, to the platinum dish and re-weigh the dish and contentsto the nearest 0.1 g to obta

37、in the weight of the specimen.NOTE 3The specimen mass proposed, based on the aluminum contentwill suffice for silicon as both elements are usually found in fuel oils atsimilar concentrations.11.2 Warm the dish and contents gently with a bunsen flameuntil the sample can be ignited. Maintain the conte

38、nts of thebasin at a temperature such that most of the combustiblematerial is removed and only carbon and ash remain.NOTE 4If the specimen contains considerable amounts of moisture,foaming and frothing can cause loss of material. If this is the case, discardthe specimen and to a fresh portion add 1

39、to 2 mL of 2-propanol beforeheating. If this is not satisfactory, add 10 mL of a mixture of equal partsof toluene and 2-propanol and mix thoroughly. Place several strips ofashless filter paper in the mixture and warm gently. When the paper beginsto burn, the greater part of the water will have been

40、removed.11.3 Place the dish and contents in a muffle furnace main-tained at a temperature of 550 6 25C. Maintain the mufflefurnace at this temperature until all the carbon is removed andonly ash remains. This may require more than 10 h in themuffle furnace and may conveniently be done overnight.11.4

41、 Cool the dish to room temperature, add 0.4 g of fluxand mix with the ash. Place the dish in a muffle furnacemaintained at a temperature of 925 6 25C for 5 min. Removethe dish and ensure contact of the flux with the ash. Replace thedish in the muffle furnace and maintain at a temperature of925 6 25C

42、 for 10 min.11.5 Remove the dish, cool the fusion melt to room tem-perature and add 50 mL of the tartaric acid/hydrochloric acidsolution. Place the dish and contents on the hot plate main-tained at a temperature of approximately 80C. Heat until themelt is dissolved. (WarningVaporization of a signifi

43、cantamount of the liquid can lead to precipitation of an insolubleform of silica leading to erroneous results.)NOTE 5Prolonged heating can be necessary to dissolve the meltcompletely and obtain a solution. Agitation or the use of magnetic stirringcan be employed to speed dissolution of the melt.11.6

44、 Allow the solution to cool and then transfer it to a100-mL flask with water, washing the dish several times toensure transfer is complete. Make up to the mark with water.Then, transfer the solution to a plastic bottle.NOTE 6Transferring the test solution to a plastic bottle is desirablebecause the

45、dilute acid solution contains fluoboric acid from dissolution ofthe flux. Storage tests have shown that there is no significant attack ofglassware in the short term (up to one week), and that the solution does notcontain fluoride ion above the 5 mg/L concentration.12. Preparation of Calibration Solu

46、tions12.1 Blank SolutionPrepare a blank solution containingonly 0.4 g flux and 50 mL of the tartaric acid/hydrochloric acidsolution diluted to 100 mL. Transfer it to a plastic bottle.12.2 AluminumPrepare a 250 mg/L aluminum workingsolution by diluting 25 mL of the 1000 mg/L standard solutionto 100 m

47、Lwith water. To each of four clean 100 mLvolumetricflasks, add 0.4 g of flux and 50 mL of the tartaric acid/hydrochloric acid solution. To successive flasks add 2, 4, 10,and 20 mL of the 250 mg/L aluminum working solution anddilute to 100 mL with water. The calibration solutions contain5, 10, 25, an

48、d 50 mg/L of aluminum, respectively.12.3 SiliconPrepare a 250 mg/L silicon working solutionby diluting 25 mL of 1000 mg/L standard solution to 100 mLwith water. To each of four clean 100 mL volumetric flasks,add 0.4 g of flux and 50 mL of the tartaric acid/hydrochloricacid solution. To successive fl

49、asks, add 2, 4, 10, and 20 mL ofthe 250 mg/L silicon working solution and dilute to 100 mLwith water. These calibration solutions contain 5, 10, 25, and50 mg/L of silicon, respectively.12.4 Transfer all calibration standards to plastic bottles.NOTE 7When both aluminum and silicon are being determined, the 5to 50 mg/L calibration solutions can be combined providing there are noincompatibility problems caused by the reagents used in the preparation ofthe standard solutions described in 7.7.1 and 7.7.2.TEST METHOD AINDUCTIVELY-COUPLEDPLASMA AT