1、Designation: D7260 12D7260 17Standard Practice forOptimization, Calibration, and Validation of InductivelyCoupled Plasma-Atomic Emission Spectrometry (ICP-AES)for Elemental Analysis of Petroleum Products andLubricants1This standard is issued under the fixed designation D7260; the number immediately
2、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 () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practi
3、ce covers information on the calibration and operational guidance for the multi-element measurements usinginductively coupled plasma-atomic emission spectrometry (ICP-AES).1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibil
4、ityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.3 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decis
5、ion on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D4057 Practice for Manual Sampling of Petroleum and Petroleum ProductsD4307 Practi
6、ce for Preparation of Liquid Blends for Use as Analytical StandardsD6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measure-ment System PerformanceD6792 Practice for Quality Management Systems in Petroleum Products, Liquid Fuels, and Lu
7、bricants Testing Laboratories2.2 ICP-AES Related Standards:C1111 Test Method for Determining Elements in Waste Streams by Inductively Coupled Plasma-Atomic Emission SpectroscopyC1109 Practice for Analysis of Aqueous Leachates from Nuclear Waste Materials Using Inductively Coupled Plasma-AtomicEmissi
8、on SpectroscopyD1976 Test Method for Elements in Water by Inductively-Coupled Argon Plasma Atomic Emission SpectroscopyD4951 Test Method for Determination of Additive Elements in Lubricating Oils by Inductively Coupled Plasma AtomicEmission SpectrometryD5184 Test Methods for Determination of Aluminu
9、m and Silicon in Fuel Oils by Ashing, Fusion, Inductively Coupled PlasmaAtomic Emission Spectrometry, and Atomic Absorption SpectrometryD5185 Test Method for Multielement Determination of Used and Unused Lubricating Oils and Base Oils by InductivelyCoupled Plasma Atomic Emission Spectrometry (ICP-AE
10、S)D5600 Test Method for Trace Metals in Petroleum Coke by Inductively Coupled Plasma Atomic Emission Spectrometry(ICP-AES)D5708 Test Methods for Determination of Nickel, Vanadium, and Iron in Crude Oils and Residual Fuels by Inductively CoupledPlasma (ICP) Atomic Emission SpectrometryD6130 Test Meth
11、od for Determination of Silicon and Other Elements in Engine Coolant by Inductively Coupled Plasma-AtomicEmission Spectroscopy1 This practice is under the jurisdiction of ASTM Committee D02 on Petroleum Products Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D
12、02.03 on Elemental Analysis.Current edition approved June 1, 2012June 1, 2017. Published August 2012June 2017. Originally approved in 2006. Last previous edition approved in 20062012 asD7260D7260 12.06. DOI: 10.1520/D7260-12.10.1520/D7260-17.2 For referencedASTM standards, visit theASTM website, www
13、.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 standard and is intended only to provide the user of an ASTM standard an indication of wha
14、t 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 cases only the current versionof the standard as published by ASTM is to be considered the
15、 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 States1D6349 Test Method for Determination of Major and Minor Elements in Coal, Coke, and Solid Residues from
16、 Combustion ofCoal and Coke by Inductively Coupled PlasmaAtomic Emission SpectrometryD6357 Test Methods for Determination of Trace Elements in Coal, Coke, and Combustion Residues from Coal UtilizationProcesses by Inductively Coupled Plasma Atomic Emission Spectrometry, Inductively Coupled Plasma Mas
17、s Spectrometry,and Graphite Furnace Atomic AbD7040 Test Method for Determination of Low Levels of Phosphorus in ILSAC GF 4 and Similar Grade Engine Oils byInductively Coupled Plasma Atomic Emission SpectrometryD7111 Test Method for Determination of Trace Elements in Middle Distillate Fuels by Induct
18、ively Coupled Plasma AtomicEmission Spectrometry (ICP-AES)D7303 Test Method for Determination of Metals in Lubricating Greases by Inductively Coupled Plasma Atomic EmissionSpectrometryD7691 Test Method for MultielementAnalysis of Crude Oils Using Inductively Coupled PlasmaAtomic Emission Spectrometr
19、y(ICP-AES)D7876 Practice for Practice for Sample Decomposition Using Microwave Heating (With or Without Prior Ashing) for AtomicSpectroscopic Elemental Determination in Petroleum Products and LubricantsD8056 Guide for Elemental Analysis of Crude OilE1479 Practice for Describing and Specifying Induct
20、ively Coupled Plasma Atomic Emission Spectrometers2.3 Other Standards:IP 437 Determination of Additive Elements in Unused Lubricating Oils and Additive Packages by Inductively CoupledPlasma-Atomic Emission Spectrometry3ISO/TC 17/SC 1 N 883 Guidelines for the Preparation of Standard Methods of Analys
21、is Using Inductively CoupledPlasma-Atomic Emission Spectrometry and for Use of ICP Spectrometry for the Determination of Chemical Composition(1991)43. Summary of Practice3.1 An Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) instrument is one that is used to determineelemental comp
22、osition of various liquid matrices. Details of the instrument components are given in Practice E1479. This practicesummarizes the protocols to be followed during calibration and verification of the instrument performance.4. Significance and Use4.1 Accurate elemental analysis of petroleum products an
23、d lubricants is necessary for the determination of chemical properties,which are used to establish compliance with commercial and regulatory specifications.4.2 Inductively Coupled Plasma-Atomic Emission Spectrometry is one of the more widely used analytical techniques in the oilindustry for multi-el
24、ement analysis as evident from at least twelve standard test methods (for example, Test Methods C1111,D1976, D4951, D5184, D5185, D5600, D5708, D6130, D6349, D6357, D7040, D7111, D7303, and D7691) published for theanalysis of fossil fuels and related materials. These have been briefly summarized by
25、Nadkarni.Nadkarni (1).54.2.1 Determination of mercury and trace metals in crude oils using atomic spectroscopic methods is discussed in Guide D8056.4.3 The advantages of using an ICP-AES analysis include high sensitivity for many elements of interest in the oil industry,relative freedom from interfe
26、rences, linear calibration over a wide dynamic concentration range, single or multi-element capability,and ability to calibrate the instrument based on elemental standards irrespective of their elemental chemical forms, within limitsdescribed below such as solubility and volatility assuming direct l
27、iquid aspiration. Thus, the technique has become a method ofchoice in most of the oil industry laboratories for metal analyses of petroleum products and lubricants.5. Apparatus5.1 SpectrometerAn inductively coupled plasma emission spectrometer with a spectral bandpass of 0.05 nm or less isrequired.
28、The spectrometer may be of the simultaneous multi-elemental or sequential scanning type. The spectrometer may be of3 Nadkarni, R. A., “Use of ICP-AES for Metal Analysis in the Oil Industry,” Available from Energy Institute, 61 New Cavendish St., London, W1G 7AR, U.K.,http:/www.energyinst.org.ICP Inf
29、ormation Newsletter, Vol 30(10), 2005, pp. 10591061.4 Winge, R. K., Peterson, V. J., and Fassel, V.A., “Inductively Coupled Plasma-Atomic Emission Spectrometry: Prominent Lines,” Applied Spectroscopy, Vol 33(3), 1979,pp. 206219 .5 Winge, R. K., Fassel, V.A., Peterson, V. J., and Floyd, M.A., “Induct
30、ively Coupled Plasma-Atomic Emission Spectrometry:AnAtlas of Spectral Information,” Elsevier,New York, 1985.6 Nygaard, D. D. and Leighty, D. A., “Inductively Coupled Plasma Emission Lines in the Vacuum Ultraviolet,” Applied Spectroscopy, Vol 39(6), 1985, pp. 968976.7 Wohlers, C. C., “Spectral Tables
31、 for Inductively Coupled Plasma Atomic Emission Spectrometry,” ICP Information Newsletter, Vol 10(8), 1985, pp. 593688.4 Boumans, P. W. J. M., “Corrections for Spectral Interferences in Optical Emission Spectrometry with Special Reference to the RF Inductively Coupled Plasma,”AvailablefromAmerican N
32、ational Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.SpectrochimicaActa, Vol 31B, 1976, pp. 147152.5 Varma, A., “CRC Handbook of Inductively Coupled Plasma Atomic Emission Spectrometry,” CRC Press, Boca Raton, FL, 1991. The boldface numbers in parenth
33、esesrefer to a list of references at the end of this standard.10 Bansal, J. B. and McElroy, F. C., “Accurate Elemental Analysis of Multigrade Lubricating Oils by ICP Method: Effect of Viscosity Modifiers,” SAE Technical Paper,932694, 1993, pp. 6168.D7260 172the air path, inert gas path, or vacuum ty
34、pe, with spectral lines selected appropriately for use with specific instrument. Either ananalog or digital readout system may be used.5.2 An ICP-AES instrument system is typically comprised of several assemblies including a radio-frequency (RF) generator,an impedance matching network (where require
35、d), an induction coil, a plasma torch, a plasma igniter system, a sample introductionsystem, a light gathering optic, an entrance slit and dispersing element to separate and measure the intensity of the wavelengthsof light emitted from the plasma, one or more devices for converting the emitted light
36、 into an electrical current or voltage, oneor more analog preamplifiers, one or more analog-to-digital converter(s), and a dedicated computer with printer. Solid state CCDor CID detectors if used may not require extra analog-to-digital components. Recently modern camera-type instruments have beensup
37、planting the photomultiplier tube type detectors. Cameras may not have high resolution, but they offer greater wavelengthchoice.5.2.1 Plasma can be monitored either axially versus radially. Potential for improved sensitivity as much as tenfold is oftenrealized with axial monitoring. However, the inc
38、reased interference from molecular background may compromise these gainsdepending on the wavelength monitored and matrix used (especially for organics versus aqueous).5.2.2 Echelle SpectrometersMore recently echelle gratings are being increasingly used in several commercial plasmaspectrometers. A pr
39、ism is used as an order-sorter to improve sensitivity. To measure widely separated lines with useful efficiency,echelle instruments have to be operated in many different orders. This involves complex wavelength scanning programs forcomputer controlled echelle monochromators. While the resolution of
40、a grating monochromator is relatively constant across itsworking range, practical resolution of an echelle monochromator can vary considerably with wavelength. Inherently highertheoretical resolving power of the echelle when used in high order, relative to the diffraction grating used in the first o
41、rder, allowsa relatively compact echelle instrument to achieve high resolving power. The detection limits obtained with echelle plasmaspectrometers are comparable to those achieved by grating spectrometers.5.3 Spectrometer Environment:5.3.1 Temperature fluctuations affect the instrument stability. S
42、ome manufacturers provide systems for maintaining a constantinternal temperature within the optical compartment and sample introduction area that assumes changes in the outside temperatureare not being controlled within the necessary specified range and rate of change to insure stability. Other manu
43、facturers design theirspectrometers to be stable over a specified temperature range without attempting to control the spectrometers internal temperature.5.3.2 Since temperature and humidity changes may also affect the sample introduction system, detectors, and electronic readoutas well as the spectr
44、ometer alignment, some manufacturers specify that care be used in selecting a location for the spectrometerthat experiences minimal variation in temperature and relative humidity. The user needs to provide a controlled environment asspecified by the manufacturer. This is a very important factor in o
45、ptimum performance of an ICP-AES system.5.3.3 The generator output power and the plasma gas flow determine the plasma temperature and thus significantly influencethe emission signal and the background. Thus, the power applied and gas flow adjustments may be used to control the signal tobackground ra
46、tio and, matrix, and some spectral interferences.5.4 Optical Path:5.4.1 Since oxygen exhibits increasing absorbance with decreasing wavelengths below 200 nm, 200 nm, the performance of anair path instrument degrades below that wavelength and is generally not useful below approximately 190 nm.190 nm.
47、5.4.2 Purging the optical path with nitrogen or argon, or another gas with low absorption in this ultraviolet region may extendthe spectral region to wavelengths below 167 nm. 167 nm. Use of these purge gases is in general less expensive to maintain thanthe vacuum path systems. Sealed optics filled
48、with an inert gas is also available for such work.5.5 Wavelength Selection:5.5.1 When selecting the fixed position wavelengths to be utilized in a Paschen-Runge polychromator for particularapplications, close collaboration between user and instrument manufacturer is critical. Camera instruments do n
49、ot have thisproblem.5.5.2 If possible, use the peak and background wavelengths suggested in the methods. When there is a choice such as with thesequential instruments, choose the wavelength that will yield signals of 100100 to 1000 the detection limit sought.Also, ensurethat the chosen wavelength will not be interfered with from unexpected elements. See Section 6.5.5.3 Often ion lines may be chosen for use over atom lines to avoid interelement interference and sensitivity of detection. Thischoice will be dependent on the analyte of interest and the sample matrix bei
