WO2007126954A1 - An infrared spectroscopy method for measuring the base number of overbased lubricants - Google Patents
An infrared spectroscopy method for measuring the base number of overbased lubricants Download PDFInfo
- Publication number
- WO2007126954A1 WO2007126954A1 PCT/US2007/007768 US2007007768W WO2007126954A1 WO 2007126954 A1 WO2007126954 A1 WO 2007126954A1 US 2007007768 W US2007007768 W US 2007007768W WO 2007126954 A1 WO2007126954 A1 WO 2007126954A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- tbn
- measuring
- bands
- carbonate
- lubricants
- Prior art date
Links
- 239000000314 lubricant Substances 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title claims abstract description 15
- 238000004566 IR spectroscopy Methods 0.000 title description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 claims abstract description 17
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims abstract description 9
- 238000010521 absorption reaction Methods 0.000 claims abstract description 8
- 238000002835 absorbance Methods 0.000 claims description 9
- 239000003921 oil Substances 0.000 description 14
- 239000010687 lubricating oil Substances 0.000 description 5
- 239000000446 fuel Substances 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 3
- 239000011593 sulfur Substances 0.000 description 3
- 229910052717 sulfur Inorganic materials 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 238000001210 attenuated total reflectance infrared spectroscopy Methods 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 230000002596 correlated effect Effects 0.000 description 2
- 239000010727 cylinder oil Substances 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000002329 infrared spectrum Methods 0.000 description 1
- 238000011005 laboratory method Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 238000004611 spectroscopical analysis Methods 0.000 description 1
- 238000010561 standard procedure Methods 0.000 description 1
- 239000010913 used oil Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/55—Specular reflectivity
- G01N21/552—Attenuated total reflection
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
- G01N21/3577—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light for analysing liquids, e.g. polluted water
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/26—Oils; viscous liquids; paints; inks
- G01N33/28—Oils, i.e. hydrocarbon liquids
- G01N33/2835—Oils, i.e. hydrocarbon liquids specific substances contained in the oil or fuel
- G01N33/2876—Total acid number
Definitions
- the present invention relates to a method for measuring a lubricant's basicity. More specifically, the present invention relates to a spectroscopic method for measuring the total base number (TBN) of overbased lubricants.
- TBN total base number
- TBN total base number
- Lubricating oils are formulated to be highly alkaline in order to neutralize the acids formed during the combustion process. Indeed, lubricating oils are routinely "overbased" with calcium carbonate.
- TBN is reported in terms of milligrams of potassium hydroxide (equivalent) per gram of lubricant (mgKOH/g), reflecting the acid neutralizing capacity relative to the strong base. Standard laboratory methods for determing TBN are ASTM D2896 and D4739. The conventional method used in the marine industry for both new and used oils is D2896.
- WO 03/073075 A2 there is disclosed a method for determining the TBN of an oil by measuring one or more selected infrared absorption bands of the oil and correlating the measured bands with the TBN. While this technique is useful in determining an oil's TBN without knowing the TBN of a fresh oil, its accuracy has a lower limit of 20 mgKOH/g.
- TBN measuring method that is amenable to onsite, online and inline measurement of lubricating oil and that is accurate over the entire range of TBN levels for overbased lubricants, nominally 0 to 100 mgKOH/g.
- the present invention comprises measuring one or more pre-selected infrared absorption bands of an oil using attenuated total reflectance infrared spectroscopy (ATR IR) and correlating the absorbance measured bands to the TBN, either at a single frequency or integrated over multiple frequencies.
- the bands measured are those due to the carbonate or sulfate species in the oil.
- Figures 1 and 2 which show the correlation of carbonate IR absorbance with TBN
- Figure 3 which shows the correlation of sulfate IR absorbance with TBN
- Attenuated total reflectance infrared spectroscopy is utilized in the present invention to monitor the presence of carbonate or sulfate species in a lubricant which then is correlated to the TBN of the lubricant.
- the present invention may be applied to fresh or in-use lubricants although their respective calibration lines may be different.
- the method is suitable for use in a laboratory and importantly in the field and is readily adaptable for use online.
- the TBN of a lubricant is determined by measuring the infrared spectrum of the lubricant using ATR IR. At least one of the absorption bands for the carbonate species is then selected. The measured absorbance (single or multiple frequencies) at the selected band is then correlated to the oil's TBN. Correlation lines are developed by comparing the absorbance for this selected band for samples on which TBN has been measured by a standard method and finding the best linear fit through the data.
- the sulfate absorption band at a frequency of 1279-1022 cm"* also shows good correlation with TBN for in-use lubricants and hence can be used in the same way as the carbonate bands described above for measuring an oil's TBN.
- Lubricating oils used in marine and stationary power plant engines are overbased with carbonate. Therefore, it is particularly preferred in the practice of the invention to determine the TBN of those oils by measuring a carbonate band, and it is most preferred to measure the band in the range of 1524-1400 cm- 1.
- the carbonate absorption band in the 1524-1400 cnr* region has within it (1475-1400 cm" ⁇ ) a strong band due to hydrocarbons which remain substantially constant at all TBN levels. Consequently, the carbonate band can be easily integrated by summing the absorbances over the frequency range.
- infrared filters may be used, for example, to exclude the hydrocarbon band at 1475-1440 cnrl or to monitor only a portion of the broad carbonate band in the 1524-1400 cm" 1 region.
- filters are used for isolating the carbonate band, separate correlation lines are required for new and used lubricants.
- Figures 1 and 2 show the correlation of carbonate IR absorbance with TBN.
- Figure 3 shows the sulfate IR absorbance with TBN.
Abstract
The present invention provides a method for measuring a lubricant's total basicity by measuring one or more preselected infrared absorption bands of a lubricant and correlating the measured bands to the basicity. Preferably, the measured bands are due to carbonate or sulfate species in the lubricant.
Description
AN INFRARED SPECTROSCOPY METHOD FOR MEASURING THE BASE NUMBER OF OVERBASED LUBRICANTS
FIELD OF THE INVENTION
[001] The present invention relates to a method for measuring a lubricant's basicity. More specifically, the present invention relates to a spectroscopic method for measuring the total base number (TBN) of overbased lubricants.
BACKGROUND OF THE INVENTION
[002] As is known, the total base number (TBN) of a lubricating oil is an important indicator of oil condition. For example, during combustion of fuel in an engine, sulfur in the fuel is ultimately converted to sulfuric acid which if not neutralized will significantly increase the wear and corrosion of the engine components.
[003] Lubricating oils are formulated to be highly alkaline in order to neutralize the acids formed during the combustion process. Indeed, lubricating oils are routinely "overbased" with calcium carbonate.
[004] The recommended range of an oil's TBN depends in part on the range of sulfur levels in the fuel being burned. Thus overbased lubricants are particularly important for marine and stationary power plant engine applications because high sulfur fuel is often burned in these engines.
[005] The ability to monitor the TBN of an oil is quite useful in evaluating whether the oil can continue to meet its intended function.
[006] TBN is reported in terms of milligrams of potassium hydroxide (equivalent) per gram of lubricant (mgKOH/g), reflecting the acid neutralizing capacity relative to the strong base. Standard laboratory methods for determing TBN are ASTM D2896 and D4739. The conventional method used in the marine industry for both new and used oils is D2896.
[007] In WO 03/073075 A2 there is disclosed a method for determining the TBN of an oil by measuring one or more selected infrared absorption bands of the oil and correlating the measured bands with the TBN. While this technique is useful in determining an oil's TBN without knowing the TBN of a fresh oil, its accuracy has a lower limit of 20 mgKOH/g.
[008] It would be advantageous to provide a TBN measuring method that is amenable to onsite, online and inline measurement of lubricating oil and that is accurate over the entire range of TBN levels for overbased lubricants, nominally 0 to 100 mgKOH/g.
SUMMARY OF THE INVENTION
[009] Broadly stated, the present invention comprises measuring one or more pre-selected infrared absorption bands of an oil using attenuated total reflectance infrared spectroscopy (ATR IR) and correlating the absorbance measured bands to the TBN, either at a single frequency or integrated over multiple frequencies. Specifically, the bands measured are those due to the carbonate or sulfate species in the oil.
BRJEF DESCRIPTION OF DRAWINGS
[010] Figures 1 and 2, which show the correlation of carbonate IR absorbance with TBN, and Figure 3, which shows the correlation of sulfate IR absorbance with TBN, illustrate the invention.
DETAILED DESCRIPTION OF THE INVENTION
[011] By way of overview, attenuated total reflectance infrared spectroscopy is utilized in the present invention to monitor the presence of carbonate or sulfate species in a lubricant which then is correlated to the TBN of the lubricant.
[012] The present invention may be applied to fresh or in-use lubricants although their respective calibration lines may be different. The method is suitable for use in a laboratory and importantly in the field and is readily adaptable for use online.
[013] It has been discovered that carbonate infrared absorption bands in the frequency range at 1524-1400 cπrl, at about 863 cnr* and at about 683 cπrl correlate with TBN. Thus in one embodiment of the present invention, the TBN of a lubricant is determined by measuring the infrared spectrum of the lubricant using ATR IR. At least one of the absorption bands for the carbonate species is then selected. The measured absorbance (single or multiple frequencies) at the selected band is then correlated to the oil's TBN. Correlation lines are developed by comparing the absorbance for this selected band for samples on which TBN has been measured by a standard method and finding the best linear fit through the data. Again, calibrations for fresh and in-use lubricants may be different.
[014] In another embodiment of the invention, the sulfate absorption band at a frequency of 1279-1022 cm"* also shows good correlation with TBN for in-use lubricants and hence can be used in the same way as the carbonate bands described above for measuring an oil's TBN.
[015] Lubricating oils used in marine and stationary power plant engines are overbased with carbonate. Therefore, it is particularly preferred in the practice of the invention to determine the TBN of those oils by measuring a carbonate band, and it is most preferred to measure the band in the range of 1524-1400 cm- 1.
[016] The carbonate absorption band in the 1524-1400 cnr* region has within it (1475-1400 cm" ^) a strong band due to hydrocarbons which remain substantially constant at all TBN levels. Consequently, the carbonate band can be easily integrated by summing the absorbances over the frequency range.
[017] Optionally, infrared filters may be used, for example, to exclude the hydrocarbon band at 1475-1440 cnrl or to monitor only a portion of the broad carbonate band in the 1524-1400 cm" 1 region. In instances where filters are used for isolating the carbonate band, separate correlation lines are required for new and used lubricants.
EXAMPLES
[018] A series of scrapedown (used) cylinder oils and a fresh cylinder oil were analyzed by ATR IR. The TBN levels of the oils as measured by ASTM D2896 ranged from 5 to 71 mgKOH/g.
[019] Carbonate bands were integrated at 1524-1400 cm-1 and at about
863 cm"1 and a sulfate band at 1279-1022 cm"1 was also integrated. Figures 1 and 2 show the correlation of carbonate IR absorbance with TBN. Figure 3 shows the sulfate IR absorbance with TBN.
Claims
1. A method for determining the TBN of a lubricant comprising: measuring one or more pre-selected infrared absorption bands of the lubricant using ATR IR; and correlating the absorbance of the measured bands to the lubricant TBN.
2. The method of claim 1 wherein the preselected bands are carbonate or sulfate bands.
3. The method of claim 1 wherein the preselected bands are due to carbonate species.
4. The method of claim 3 wherein the bands are between 1524-1400 cm~l .
5. The method of claim 3 wherein the band is at about 863 cm"1.
6. The method of claim 1 wherein the preselected bands are due to sulfate species.
7. The method of claim 6 wherein the bands are between 1279-1022 cm~l .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP07754309A EP2002239A1 (en) | 2006-03-31 | 2007-03-28 | An infrared spectroscopy method for measuring the base number of overbased lubricants |
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US78823606P | 2006-03-31 | 2006-03-31 | |
| US60/788,236 | 2006-03-31 | ||
| US11/713,407 | 2007-03-02 | ||
| US11/713,407 US7442936B2 (en) | 2006-03-31 | 2007-03-02 | Infrared spectroscopy method for measuring the base number of overbased lubricants |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2007126954A1 true WO2007126954A1 (en) | 2007-11-08 |
Family
ID=38352970
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/US2007/007768 WO2007126954A1 (en) | 2006-03-31 | 2007-03-28 | An infrared spectroscopy method for measuring the base number of overbased lubricants |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US7442936B2 (en) |
| EP (1) | EP2002239A1 (en) |
| WO (1) | WO2007126954A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101865839A (en) * | 2010-07-13 | 2010-10-20 | 中国人民解放军总后勤部油料研究所 | Method for rapidly monitoring production of lubricating oil |
| CN103323421A (en) * | 2013-07-10 | 2013-09-25 | 中国人民解放军海军后勤技术装备研究所 | Method for identifying engine lubricating oil infrared fingerprint spectrogram |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080207474A1 (en) * | 2006-12-11 | 2008-08-28 | Klaus-Werner Damm | Method and system for detecting leaks in stuffing box of two-stroke engines |
| BRPI0801639B1 (en) * | 2008-06-03 | 2018-04-10 | Petróleo Brasileiro S.A. - Petrobras | METHOD FOR DETERMINING THE TOTAL ACIDITY NUMBER AND THE NUMBER OF ACADEMIC ACIDITY OF OILS, OIL COURTS AND WATER-IN-OIL TYPE OF OIL BY MEDIUM INFRARED SPECTROSCOPY |
| CN101806794B (en) * | 2010-03-31 | 2013-02-20 | 中国人民解放军总后勤部油料研究所 | Quick identification method of engine lubricating oil types |
| CN106323904A (en) * | 2015-06-30 | 2017-01-11 | 上海梅山钢铁股份有限公司 | Detection method of content of sulfur in sulfur iron alloy |
| EP3417274A1 (en) | 2016-02-15 | 2018-12-26 | ExxonMobil Research and Engineering Company | Systems and methods for authenticating working fluids |
| CN108700505A (en) | 2016-02-15 | 2018-10-23 | 埃克森美孚研究工程公司 | The method and system identified in situ for working fluid |
| US10845356B2 (en) * | 2017-12-15 | 2020-11-24 | Exxonmobil Research And Engineering Company | Determination of total base number in lubricants |
| US11262298B2 (en) * | 2018-08-30 | 2022-03-01 | Caterpillar Inc. | System and method for determining fluid origin |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030164451A1 (en) * | 2002-02-26 | 2003-09-04 | Reischman Paul Thomas | Method for the analysis of lubricant basicity |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
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| FR2486246A1 (en) | 1980-07-04 | 1982-01-08 | Elf France | Determn. of carbonate basicity, esp. of oils - by treating with acid and IR analysis of carbon di:oxide released |
| DD243349A1 (en) | 1985-12-03 | 1987-02-25 | Zeitz Hydrierwerk | METHOD FOR EVALUATING THE STABILITY OF THE CARBONATE RESERVE IN LUBRICATE ADDITIVES |
| US4780224A (en) * | 1987-12-07 | 1988-10-25 | Texaco Inc. | Method of preparing overbased calcium sulfonates |
| JP3192209B2 (en) | 1992-04-17 | 2001-07-23 | 日石三菱株式会社 | Method for measuring insolubles in marine engine oil |
| US5537336A (en) * | 1994-03-30 | 1996-07-16 | On-Site Analysis, Inc. | On-site oil analyzer |
| JPH10298583A (en) | 1997-04-30 | 1998-11-10 | Kobe Steel Ltd | Lubricant for squeeze-drawing |
| EP1232388A2 (en) * | 1999-11-19 | 2002-08-21 | Battelle Memorial Institute | An apparatus for machine fluid analysis |
| JP2002350339A (en) | 2001-05-25 | 2002-12-04 | Horiba Ltd | Method for analyzing particulate material in exhaust gas from engine |
| US20040142827A1 (en) | 2001-11-29 | 2004-07-22 | Palazzotto John D. | Sulfur containing lubricating oil additive system particularly useful for natural gas fueled engines |
| US6642191B2 (en) | 2001-11-29 | 2003-11-04 | Chevron Oronite Company Llc | Lubricating oil additive system particularly useful for natural gas fueled engines |
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| US7299682B2 (en) * | 2005-10-14 | 2007-11-27 | The Lubrizol Corporation | Method and apparatus for estimating basicity of a used, all-loss cylinder lubricant |
-
2007
- 2007-03-02 US US11/713,407 patent/US7442936B2/en active Active
- 2007-03-28 EP EP07754309A patent/EP2002239A1/en not_active Ceased
- 2007-03-28 WO PCT/US2007/007768 patent/WO2007126954A1/en active Application Filing
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030164451A1 (en) * | 2002-02-26 | 2003-09-04 | Reischman Paul Thomas | Method for the analysis of lubricant basicity |
Non-Patent Citations (1)
| Title |
|---|
| KUDLATY K ET AL: "Development of an infrared sensor for on-line analysis of lubricant deterioration", PROCEEDINGS OF IEEE SENSORS 2003. 2ND. IEEE INTERNATIONAL CONFERENCE ON SENSORS. TORONTO, CANADA, OCT. 22 - 24, 2003, IEEE INTERNATIONAL CONFERENCE ON SENSORS, NEW YORK, NY : IEEE, US, vol. VOL. 2 OF 2. CONF. 2, 22 October 2003 (2003-10-22), pages 903 - 908Vol2, XP010691040, ISBN: 0-7803-8133-5 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101865839A (en) * | 2010-07-13 | 2010-10-20 | 中国人民解放军总后勤部油料研究所 | Method for rapidly monitoring production of lubricating oil |
| CN103323421A (en) * | 2013-07-10 | 2013-09-25 | 中国人民解放军海军后勤技术装备研究所 | Method for identifying engine lubricating oil infrared fingerprint spectrogram |
Also Published As
| Publication number | Publication date |
|---|---|
| US7442936B2 (en) | 2008-10-28 |
| US20070228281A1 (en) | 2007-10-04 |
| EP2002239A1 (en) | 2008-12-17 |
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