1、Designation: D3605 00 (Reapproved 2011)D3605 16Standard Test Method forTrace Metals in Gas Turbine Fuels by Atomic Absorptionand Flame Emission Spectroscopy1This standard is issued under the fixed designation D3605; the number immediately following the designation indicates the year oforiginal adopt
2、ion 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 Scope*1.1 This test method covers the determination of sodium, lead, calcium
3、, and vanadium in Specification D2880 Grade Nos. 1-GTand 2-GT fuels in the0-GT through 4-GT fuels at 0.5 mg range from 0.1 to 2.0 mg/L.kg level for each of the elements. This testmethod is intended for the determination of oil-soluble metals and not waterborne contaminants in oil-water mixtures.1.1.
4、1 Test Method D6728 is suggested as an alternative test method for the determination of these elements in SpecificationD2880.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all
5、 of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D2880 Specification for
6、 Gas Turbine Fuel OilsD4057 Practice for Manual Sampling of Petroleum and Petroleum ProductsD4177 Practice for Automatic Sampling of Petroleum and Petroleum ProductsD6728 Test Method for Determination of Contaminants in Gas Turbine and Diesel Engine Fuel by Rotating Disc ElectrodeAtomic Emission Spe
7、ctrometry3. Summary of Test Method3.1 The samples are prepared to conform with the requirements of the method of standard additions, which is selected to obviateproblems encountered with the direct analysis of typical gas turbine fuels that exhibit significant variations in physical properties.Diffe
8、rent, but known, amounts of analyte are added to two portions of sample. These, together with the unaltered sample, areburned in the flame of an atomic absorption instrument that measures light absorption by the atomized metals. The analysis of thesample portions with added analyte provides the cali
9、bration information necessary to calculate the analyte content of the unalteredsample.3.2 Lead is determined by atomic absorption in a premixed air-acetylene flame, and sodium is determined by atomic absorptionor atomic emission in a premixed air-acetylene flame. Calcium and vanadium are determined
10、by atomic absorption or atomicemission in a premixed nitrous oxide-acetylene flame.3.3 Most experience with this test method has been in the atomic absorption mode, although flame emission has been usedsuccessfully. Details in the subsequent sections are written for the atomic absorption mode. If th
11、e flame emission mode is used,minor details in the subsequent sections must be altered to conform to standard practice for flame emission spectroscopy. Theprecision statement applies only to the atomic absorption mode.NOTE 1Some GT fuel users may wish to determine potassium in addition to other meta
12、ls included in this method. Potassium can be determined ina manner similar to that for sodium using a potassium hollow cathode lamp, (unless flame emission mode is used) a wavelength of 766.4 mm, 766.4 mm,1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products Produc
13、ts, Liquid Fuels, and Lubricantsand is the direct responsibility ofSubcommittee D02.03 on Elemental Analysis.Current edition approved May 1, 2011July 1, 2016. Published May 2011July 2016. Originally approved in 1977. Last previous edition approved in 20052011 as D3605 00(2011). (2005). DOI: 10.1520/
14、D3605-00R11.10.1520/D3605-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM sta
15、ndard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cas
16、es only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1and an appropri
17、ate organo-potassium standard. Precision data for potassium have not been determined.4. Significance and Use4.1 Knowledge of the presence of trace metals in gas turbine fuels enables the user to predict performance and, when necessary,to take appropriate action to prevent corrosion.5. Apparatus5.1 A
18、tomic Absorption Spectrophotometer, capable of measuring radiation over the wavelength range from 280280 nm to 600nm. 600 nm. The instrument must be capable of measuring low-level signals (approximately 1 % absorption or 0.004 absorbanceunit per mg/L milligram per litre vanadium). The instrument sho
19、uld also be equipped as follows.5.1.1 Burner, with variable nebulizer and auxiliary oxidant supply to reduce non-atomic absorption from unburnedhydrocarbons which cause interferences.5.1.1.1 Burner Head, capable of supporting a nitrous oxide-acetylene flame.5.1.1.2 Burner Head, single- or multiple-s
20、lot, capable of supporting an air-acetylene flame.5.1.2 Electronic Detection System, capable of reading to the nearest 0.1 % absorption or 0.0004 absorbance.5.1.2.1 The text describes the measurement of absorption signals that is, either percent absorption or absorbance. Forinstruments reading in pe
21、rcent absorption, absorption signals of 0.1 % absorption must be measurable. For instruments reading inabsorbance, signals of 0.0004 absorbance must be measurable.5.1.3 Hollow Cathode Lamp Power Supply, regulated to minimize drift.5.1.4 Monochromator, capable of resolving the 318.34318.34 nm 318.40-
22、nm318.40 nm vanadium doublet from the 318.54-nm318.54 nm vanadium line.5.1.5 Hollow Cathode Lamps, one each for calcium, sodium, lead, and vanadium.NOTE 2Electrodeless-discharge lamps can be an acceptable alternative, but the precision of this method was determined with hollow cathode lamps.5.1.6 Wh
23、en the instrument has flame-emission capability, the emission technique can be used for the analyses of sodium,calcium, and vanadium.5.2 Volumetric Flasks, 25-mL.25 mL.5.3 Glass Vials, 40-mL,40 mL, screw-cap type, polyethylene-lined caps.5.4 Syringe, 100-L,100 L, Hamilton type or equivalent.6. Reage
24、nts6.1 Purity of ReagentsReagent grade chemicals shall be used in tests. Unless otherwise indicated, it is intended that allreagents conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society where suchspecifications are available.3 Other grades may be use
25、d, provided it is ascertained that the reagent is of sufficiently high purity topermit its use without lessening the accuracy of the determination.6.2 1,2,3,4-tetrahydronaphthalene,4practical grade, analyte-sterile.NOTE 3Analyte-sterile 1,2,3,4-tetrahydronaphthalene can be prepared by extracting a p
26、ortion of tetralin with an equal amount of hydrochloric acidin a covered screw-cap vial. Heat the vial on a steam bath for 1 h and shake the vial for 1 h. If the acid extracted 1,2,3,4-tetrahydronaphthalene andunextracted 1,2,3,4-tetrahydronaphthalene give indistinguishable absorption signals for ea
27、ch of the analytes under optimal experimental conditions, theunextracted 1,2,3,4-tetrahydronaphthalene can be used throughout this method.6.3 Organometallic StandardsOil-soluble salts of sodium, lead, calcium, and vanadium of known concentration.56.4 Mixed StandardPrepare a mixed standard containing
28、 250250 mg mg/L L each of sodium, lead, calcium, and vanadiumby dissolving the appropriate amounts of organometallic standards in 1,2,3,4-tetrahydronaphthalene and making the requireddilutions. Prepare fresh daily, as needed.6.5 Quality Control Samples, preferably are portions of one or more liquid
29、petroleum materials that are stable and representativeof the samples of interest. These QC samples can be used to check the validity of the testing process as described in Section 8.7. Sampling7.1 Samples shall be taken in accordance with the instructions in Practice D4057 or D4177.3 Reagent Chemica
30、ls, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and Nationa
31、lFormulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville, MD.4 Tetralin (1,2,3,4-tetrahydronaphthalene), manufactured by E. I. duPont de Nemours and Co., has been found satisfactory. If you are aware of alternative suppliers, pleaseprovide this information to ASTM International Headquarter
32、s. Your comments will receive careful consideration at a meeting of the responsible technical committee,1whichyou may attend.5 Conostan standards, available from Conostan Division, Continental Oil Co., Ponca City, OK 74601, were used in determining the precision quoted in this method. Otherstandards
33、 are available from the Office of Standard Reference Materials, Room B314, Chemistry Bldg., National Institute of Standards and Technology, Washington, DC20234, and from Angstrom, Inc., P. O. Box 252, Belleville, MI 48111, but the precision statement may or may not apply to results obtained with the
34、se standards.D3605 1628. Procedure8.1 Fill two clean 25-mL25 mL volumetric flasks to the line with sample. With the microlitre syringe add 50 L 50 L of mixedstandard to one flask and 100 L 100 L to the other. Touch the needle of the syringe to the inner wall of the flask to ensurequantitative transf
35、er of the standard. Invert and mix the contents. (The two flasks are now spiked with 0.50.5 mg mg/L L and1.01.0 mg mg/L L of sodium, lead, calcium, and vanadium). Alternatively, weigh 25.0 g 25.0 g of sample into each of two cleandisposable glass vials and add the standard in the same manner. (The t
36、wo vials are now spiked with 0.50.5 mg mg/kg kg and1.01.0 mg mg/kg kg of sodium, lead, calcium, and vanadium.)8.2 Prepare a third spiked sample by adding approximately 1 mL of the mixed standard to approximately 25 mL 25 mL ofsample. This solution serves only to aid in establishing satisfactory oper
37、ating conditions for the atomic absorption instrument.8.3 Establish the atomic absorption instrument operating conditions, which are recommended by the manufacturer, and considerthe following special points. Select the mode, flame gases, and spectral lines from the information presented in Table 1.8
38、.4 Analysis:8.4.1 With the atomic absorption instrument in operation for monitoring lead absorption and with 1,2,3,4-tetrahydronaphthalenenebulizing, zero the instrument. Aspirate into the flame the third spiked sample described in 8.2 and note the net lead absorptionsignal. Optimize experimental co
39、nditions by adjusting the burner position (relative to the hollow cathode beam), the flow rates ofthe fuel and oxidant gases, and the sample aspiration rate until the net lead absorption signal maximizes. Re-zero the instrumentwith 1,2,3,4-tetrahydronaphthalene nebulizing, and consecutively introduc
40、e into the flame the unaltered sample and the two spikedsamples, with 1,2,3,4-tetrahydronaphthalene nebulizing between each sample. Record the absorption signal of each sample and ofeach blank between samples.8.4.1.1 At optimal experimental conditions, the analyte concentration that accounts for 1 %
41、 absorption should be approximately11 mg mg/L. L. The percent absorption to concentration ratio must be near unity in order to achieve the lower limits of detectionthat are required. This note does not apply to flame emission measurements.8.4.2 With the atomic absorption instrument in operation for
42、monitoring vanadium absorption and with 1,2,3,4-tetrahydronaphthalene nebulizing, zero the instrument. Introduce into the flame the third spiked sample described in 8.2. Recordthe net vanadium absorption signal. Optimize the experimental conditions as in 8.4.1. Re-zero the instrument with 1,2,3,4-te
43、trahydronaphthalene nebulizing and consecutively introduce into the flame the unaltered sample and the two spiked samples.Record the absorption signal of each sample and of each 1,2,3,4-tetrahydronaphthalene blank between samples.8.4.3 With the atomic absorption instrument in operation for monitorin
44、g sodium absorption, zero the instrument with1,2,3,4-tetrahydronaphthalene nebulizing, and consecutively introduce into the flame the unaltered sample and the two spikedsamples. Record the absorption signal of each sample and of each 1,2,3,4-tetrahydronaphthalene blank between samples.NOTE 4For dete
45、rmining sodium and calcium, the maximization of absorption or emission signals is not critical.8.4.4 With the atomic absorption instrument in operation for monitoring calcium absorption, zero the instrument with1,2,3,4-tetrahydronaphthalene nebulizing, and consecutively introduce into the flame the
46、unaltered sample and the two spikedsamples. Record the absorption signal of each sample and of each 1,2,3,4-tetrahydronaphthalene blank between samples.9. Calculation9.1 For each absorption signal, calculate the net absorption signal as follows:a 5A 2b11b2!/2# (1)where:a = net absorption signal,A =
47、observed absorption signal,b1 = blank signal before the sample, andb2 = blank signal after the sample.NOTE 5Blank corrections are usually small. If a large drift in blank signals is observed during a series of measurements, some experimental parameteris out of control. The cause of the variation sho
48、uld be corrected, and the measurements repeated.9.2 For each element in turn, calculate sensitivities as follows:TABLE 1 Experimental ConditionsElement Mode Wavelength, nm Fuel OxidantNa Absorption 589.6 C2H2 airNa Emission 589.6 C2H2 airPb Absorption 283.3 C2H2 airCa Absorption 422.7 C2H2 N2OCa Emi
49、ssion 422.7 C2H2 N2OV Absorption 318.34318.40 C2H2 N2OV Emission 437.9 C2H2 N2OD3605 163S0.552a12a2! (2)S1.05a32a2! (3)S 5S0.51S1.0!/2 (4)where:S0.5 = sensitivity for the 0.5-mg/L spiked sample,S0.5 = sensitivity for the 0.5 mgL spiked sample,S1.0 = sensitivity for the 1.0-mg/L spiked sample,S1.0 = sensitivity for the 1.0 mgL spiked sample,S = average sensitivity,a1 = net absorption signal for the 0.5-mg/L spiked sample,a1 = net absorption signal for the 0.5 mgL spiked sample,a2 = net absorption signal for the unaltered sample, anda3 = net absorpt
