ASTM D5184-2012 Standard Test Methods for Determination of Aluminum and Silicon in Fuel Oils by Ashing Fusion Inductively Coupled Plasma Atomic Emission Spectrometry and Atomic Abs.pdf

1、Designation: D5184 12Standard 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 designation D5184; the number immediately following the

2、 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 () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These test methods cover

3、 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 quantita-tively determine aluminum and silicon.1.3 Te

4、st 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 This standard does not purport to address all o

5、f 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 warningstatements are given in Sections 7.6, 10.1, and 1

6、1.5.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6299 Practice for Applying Statistical Quality Assuranceand Control Charti

7、ng Techniques to Evaluate AnalyticalMeasurement System PerformanceD6792 Practice for Quality System in Petroleum Productsand Lubricants Testing LaboratoriesD7260 Practice for Optimization, Calibration, and Valida-tion of Inductively Coupled Plasma-Atomic EmissionSpectrometry (ICP-AES) for Elemental

8、Analysis of Petro-leum Products and LubricantsD7740 Practice for Optimization, Calibration, and Valida-tion of Atomic Absorption Spectrometry for Metal Analy-sis of Petroleum Products and LubricantsE135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related Materials3. Terminology

9、3.1 Definitions:3.1.1 emission spectroscopy, nRefer to TerminologyE135.3.2 Definitions of Terms Specific to This Standard:3.2.1 calibration, nthe process by which the relationshipbetween signal intensity and elemental concentration is deter-mined for a specific element analysis.3.2.2 check standard,

10、 nin calibration, an artifact measuredperiodically, the results of which typically are plotted on acontrol 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

11、 and the carbon finally removed by heating in a mufflefurnace at a temperature of 550 6 25C. The residue is 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 resultingsolutio

12、n is aspirated into an inductively-coupled plasma andthe emission intensities of aluminum and silicon lines aremeasured. Standard calibration solutions are also aspirated andaluminum and silicon intensities are measured for comparison.1These test methods are under the jurisdiction of ASTM Committee

13、D02 onPetroleum Products and Lubricants and are the direct responsibility of Subcommit-tee D02.03 on Elemental Analysis.Current edition approved June 1, 2012. Published August 2012. Originallyapproved in 1991. Last previous edition approved in 2006 as D5184 01(2006).DOI: 10.1520/D5184-12.2For refere

14、nced 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.*A Summary of Changes section appears at the end of this standardCopyrig

15、ht ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1Alternatively, the resulting solution is aspirated into the flameof an atomic absorption spectrometer and the absorptions of theresonance radiation of aluminum and silicon are measured.Standard

16、 calibration solutions are also aspirated and aluminumand silicon absorption intensities are measured for comparison.4.2 Information on proper protocols for conducting atomicabsorption spectrometry can be found in Practice D7740.4.3 Information on Proper protocols for conducting induc-tively coupled

17、 plasma-atomic absorption spectrometry can befound in Practice D7260.5. Significance and Use5.1 Catalyst fines in fuel oils can cause abnormal enginewear. These test methods provide a means of determiningsilicon and aluminum, the major constituents of the catalysts.6. Apparatus6.1 Balance, capable o

18、f weighing to 0.1 g, capacity of150 g.6.2 Choice of Instrument:6.2.1 Inductively-Coupled Plasma Atomic EmissionSpectrometerEither a sequential or simultaneous spectrom-eter is suitable, if equipped with an ICP torch and RF generatorto form and sustain the plasma.6.2.2 Atomic Absorption SpectrometerA

19、 suitable instru-ment will consist of modulated hollow cathode lamps or othersources of resonance radiation of aluminum and silicon, anitrous oxide/acetylene burner, and a spectrometer with asuitable detection and read-out system.6.3 Homogenizer, non-aerating, high-speed shear mixer tohomogenize the

20、 sample.NOTE 1Ultrasonic bath and ultrasonic probe type homogenizers werenot evaluated in the development of these test methods.6.4 Electric Muffle Furnace, capable of being maintained attemperatures of 550 6 25C and 925 6 25C. The furnacepreferably having suitable apertures at front and rear to all

21、owa 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 temperature 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, c

22、leaned with fusedpotassium hydrogen sulfate.6.10 Volumetric Flasks, 100 and 1000 mL.6.11 All glassware must be carefully cleaned with 1 + 1hydrochloric acid and rinsed thoroughly with water to mini-mize contamination. The use of chromic acid cleaning solutionis not recommended.6.12 Zirconium crucibl

23、e with close fitting zirconium lid, 30to 50 mL capacity.7. Reagents7.1 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 Societ

24、y wheresuch specifications are available.3Other 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.7.2 Purity of WaterUnless otherwise indicated, referenceto water shall be understood

25、 to mean reagent water conformingto Type II of Specification D1193.7.3 FluxMixture of 90 % lithium tetraborate and 10 %lithium fluoride.NOTE 2Lithium fluoride 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)conc

26、entrated hydro-chloric acid.7.5 Potassium Hydrogen Sulfate, fused solid.7.6 2-Propanol (Isopropyl Alcohol) (WarningFlammable; can be explosive when evaporated to or neardryness.)7.7 Aqueous Standard Solutions .7.7.1 Aluminum Standard SolutionsObtain a ready made,aqueous standard or prepare a standar

27、d 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 arbitrarylength of 99.99 % minimum purity aluminum wire (2 mmdiameter aluminum wire has been found satisfactory). Measurethe length to the nearest 0.1 cm and w

28、eigh 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 slightly 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 hydrochlor

29、ic acid. Heat gently. Cooland transfer the solution to 1000 mL volumetric flask. Dilute tothe mark with water.7.7.2 Silicon Standard SolutionsObtain a ready 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

30、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) with8gofsodium hydroxideuntil a clear melt is obtained. Cool and dissolve the melt in100 mLof a solution of 1 part hydrochloric acid by volume and2 parts wate

31、r by volume. Transfer this solution to a 1000 mL3Reagent 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

32、 Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.D5184 122volumetric flask and dilute to the mark with water.Immediately, transfer the contents of the flask to a plasticbottle.7.8 Tartaric Acid/Hydrochloric Acid Soluti

33、onDissolve 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 Quality Control (QC) Samples, preferably are portionsof o

34、ne 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 Preparation8.1 Preparation of QC Samples shall follow the sameprotocol

35、 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 inPractice D4057 or D4177 . Typically, a gallon size conta

36、inerfilled to approximately three-fourths of capacity is satisfactory.10. Sample Handling10.1 HomogenizationIt is extremely important to homog-enize the fuel oil in the sample container in order to obtain arepresentative specimen. (WarningFailure to use this ho-mogenization procedure can invalidate

37、the results becausenon-representative aliquots could be obtained and this couldlead to erroneous results.)10.2 Place the sample container in 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 t

38、he sample container so that the head of the shaft isimmersed to approximately 5 mm from the bottom of thesample vessel. Mix the sample for about 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-mix

39、ed sample, preferably containing about 1.3 mgaluminum, to the platinum dish and re-weigh the dish andcontents to the nearest 0.1 g to obtain the weight of thespecimen.NOTE 3The specimen mass proposed, based on the aluminum contentwill suffice for silicon as both elements are usually found in fuel oi

40、ls atsimilar concentrations.11.2 Warm the dish and contents gently with a bunsen flameuntil the sample can be ignited. Maintain the contents 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 am

41、ounts of moisture,foaming and frothing can cause loss of material. If this is the case, discardthe specimen and to a fresh portion add 1 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

42、strips ofashless filter paper in the mixture and warm gently. When the paper beginsto burn, the greater part of the water will have been 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 th

43、e carbon is removed andonly ash remains. This may require more than 10 h in themuffle furnace and may conveniently be done overnight.11.4 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. Re

44、movethe dish and ensure contact of the flux with the ash. Replace thedish in the muffle furnace and maintain at a temperature of925 6 25C 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 conten

45、ts on the hot plate main-tained at a temperature of approximately 80C. Heat until themelt is dissolved. (WarningVaporization of a significantamount of the liquid can lead to precipitation of an insolubleform of silica leading to erroneous results.)NOTE 5Prolonged heating can be necessary to dissolve

46、 the meltcompletely and obtain a solution. Agitation or the use of magnetic stirringcan be employed to speed dissolution of the melt.11.6 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 wit

47、h water.Then, transfer the solution to a plastic bottle.NOTE 6Transferring the test solution to a plastic bottle is desirablebecause the dilute acid solution contains fluoboric acid from dissolution ofthe flux. Storage tests have shown that there is no significant attack ofglassware in the short ter

48、m (up to one week), and that the solution does notcontain fluoride ion above the 5 mg/L concentration.12. Preparation of Calibration Solutions12.1 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

49、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 mLwith 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, and 50 mg/L of aluminum, respectively.12.3 SiliconPrepare a 250 mg/L silicon working solutionby diluting 25 mL of