This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Quantification of Active Antioxidants by FTIR Spectroscopy and the Correlation to Measured TBN Values
Technical Paper
2001-01-3599
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
Total base number (TBN) measurement is traditionally used to assess the ability of an engine oil to neutralize the generated acids during engine operation. Although such measurements are informative, they can only determine the total quantity of the remaining antioxidants in the engine oil, and not the amount of active antioxidants that can effectively neutralize the acids. The work presented here investigates the activity of antioxidants in fresh and used engine oils by Fourier Transformed Infrared Spectroscopy (FTIR) and their correlation to the TBN values obtained by titration. The method is based on the reaction of an acid solution with the alkaline ingredient of the engine oil in a non-polar solvent that mimics the actual environment experienced by the antioxidants. FTIR Spectroscopy is used to monitor the consumption of the acid. The decrease in peak intensity of the acid is then employed to quantify the remaining active antioxidants through a calibration curve.
According to the experimental results, FTIR values correlate well with TBN values for fresh oils, however, lesser correlations were found for used engine oils. These results tend to indicate that oil contamination may have an inhibition effect on the activity of antioxidants and that titrometric TBN measurements do not adequately represent the neutralization ability of used engine oils. The FTIR method described herein could serve as a valuable tool to assess the remaining useful life of the oil and complement selected condition monitoring methods (such as viscosity measurements, elemental analysis, etc.) employed in preventive/predictive maintenance programs.
Recommended Content
Technical Paper | TBN Retention - Are We Missing the Point? |
Technical Paper | Experience with a New York City Taxicab Fleet Test |
Technical Paper | ENGINES OF THE AIR |
Authors
Citation
Taghizadeh, A. and D'Souza, M., "Quantification of Active Antioxidants by FTIR Spectroscopy and the Correlation to Measured TBN Values," SAE Technical Paper 2001-01-3599, 2001, https://doi.org/10.4271/2001-01-3599.Also In
References
- “Standard Test Method for Base Number of Petroleum Products by Potentiometric Perchloric Acid Titration” Annual Book of ASTM Standards 5.02 Philadelphia, PA 1995
- “Standard Test Method for Base Number Determination by Potentiometric Titration” Annual Book of ASTM Standards 5.03 Philadelphia, PA 1995
- Kauffman R.E. “Rapid, Portable Voltammetric Techniques for Performing Antioxidant, Total Acid Number (TAN) and Total Base Number (TBN) Measurements” STLE Presentation at the 52 nd Annual meeting Kansas City, Missouri May 1997
- Jefferies A. Ameye J. “RULER and Used Engine Oil Analysis Programs” Paper Presentation at the World Tribology Congress London, UK 1997
- Kauffman R.E. “Remaining Useful Life Measurements of Diesel Engine Oils, Automotive Engine Oils, Hydraulic Fluids, and Grease Using Cyclic Voltammetric Methods” Lubr. Eng. 51 3 223 229 1994
- Van Dam W. Freerks R.L. Small V.R. Willis W.W. “TBN Retention-Are We Missing the Point?” SAE Paper No. 972950 1997