Significance and Use
This test method covers the rapid determination of 22 elements in used lubricating oils and in base oils, and it provides rapid screening of used oils for indications of wear. Test times approximate a few minutes per test specimen, and detectability for most elements is in the low mg/kg range. In addition, this test method covers a wide variety of metals in virgin and re-refined base oils. Twenty-two elements can be determined rapidly, with test times approximating several minutes per test specimen.
When the predominant source of additive elements in used lubricating oils is the additive package, significant differences between the concentrations of the additive elements and their respective specifications can indicate that the incorrect oil is being used. The concentrations of wear metals can be indicative of abnormal wear if there are baseline concentration data for comparison. A marked increase in boron, sodium, or potassium levels can be indicative of contamination as a result of coolant leakage in the equipment. This test method can be used to monitor equipment condition and define when corrective actions are needed.
The concentrations of metals in re-refined base oils can be indicative of the efficiency of the re-refining process. This test method can be used to determine if the base oil meets specifications with respect to metal content.
1.1 This test method covers the determination of additive elements, wear metals, and contaminants in used lubricating oils by inductively coupled plasma atomic emission spectrometry (ICP-AES). The specific elements are listed in Table 1.
1.2 This test method covers the determination of selected elements, listed in Table 1, in re-refined and virgin base oils.
1.3 For analysis of any element using wavelengths below 190 nm, a vacuum or inert-gas optical path is required. The determination of sodium and potassium is not possible on some instruments having a limited spectral range.
1.4 This test method uses oil-soluble metals for calibration and does not purport to quantitatively determine insoluble particulates. Analytical results are particle size dependent, and low results are obtained for particles larger than a few micrometers.
1.5 Elements present at concentrations above the upper limit of the calibration curves can be determined with additional, appropriate dilutions and with no degradation of precision.
1.6 For elements other than calcium, sulfur, and zinc, the low limits listed in Table 2 and Table 3 were estimated to be ten times the repeatability standard deviation. For calcium, sulfur, and zinc, the low limits represent the lowest concentrations tested in the interlaboratory study.
1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific warning statements are given in 6.1, 8.2, and 8.4.
TABLE 1 Elements Determined and Suggested WavelengthsA
|Aluminum||308.22, 396.15, 309.27|
|Barium||233.53, 455.40, 493.41|
|Calcium||315.89, 317.93, 364.44, 422.67|
|Magnesium||279.08, 279.55, 285.21|
|Manganese||257.61, 293.31, 293.93|
|Nickel||231.60, 227.02, 221.65|
|Phosphorus||177.51, 178.29, 213.62, 214.91, 253.40|
|Sulfur||180.73, 182.04, 182.62|
|Titanium||337.28, 350.50, 334.94|
|Vanadium||292.40, 309.31, 310.23, 311.07|
|Zinc||202.55, 206.20, 213.86, 334.58, 481.05|
A These wavelengths are only suggested and do not represent all possible choices.
TABLE 2 Repeatability
|Element||Range, mg/kg||Repeatability, μg/gA|
A where: X = mean concentration, μg/g.
TABLE 3 Reproducibility
|Element||Range, mg/kg||Reproducibility, μg/gA|
A where: X = mean concentration, μg/g.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
C1109 Practice for Analysis of Aqueous Leachates from Nuclear Waste Materials Using Inductively Coupled Plasma-Atomic Emission Spectroscopy
D1552 Test Method for Sulfur in Petroleum Products (High-Temperature Method)
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D4307 Practice for Preparation of Liquid Blends for Use as Analytical Standards
D4628 Test Method for Analysis of Barium, Calcium, Magnesium, and Zinc in Unused Lubricating Oils by Atomic Absorption Spectrometry
D4927 Test Methods for Elemental Analysis of Lubricant and Additive Components--Barium, Calcium, Phosphorus, Sulfur, and Zinc by Wavelength-Dispersive X-Ray Fluorescence Spectroscopy
D4951 Test Method for Determination of Additive Elements in Lubricating Oils by Inductively Coupled Plasma Atomic Emission Spectrometry
E135 Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
additive-elements; aluminum; barium; boron; calcium; chromium; copper; emission-spectrometry; ICP; inductively coupled plasma atomic emission spectrometry; iron; lead; lubricating oils; magnesium; manganese; molybdenum; nickel; phosphorous, potassium; silicon; silver; sodium; sulfur; tin; titanium; vanadium; wear metals; zinc; Additives--lubricating oils; Additives--petroleum products; Aluminum content--petroleum products; Barium content--petroleum products; Base oils; Boron; Calcium content--petroleum products; Chromium; Contamination--petroleum products; Titanium (Ti)/alloys; Vanadium content--petroleum products; Wear metals; Zinc content--petroleum products; Copper content--petroleum products; Fuel sulfur; Nickel content--petroleum products; ICP-AES (inductively-coupled plasma atomic emission spectrometry); Iron; Lead metals/alloys; Phosphorus content--petroleum products; Lubricating oils; Magnesium content--petroleum products; Manganese content--petroleum products; Potassium content--petroleum products; Molybdenum; Silicon content--petroleum products; Silver; Sodium content--petroleum products; Tin metals/alloys ;
ICS Number Code 71.040.50 (Physicochemical methods of analysis); 75.100 (Lubricants, industrial oils and related products)
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