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
BRIEF DESCRIPTION OF DRAWINGS
FIGS. 1 and 2, which show the correlation of carbonate IR absorbance with TBN, and FIG. 3, which shows the correlation of sulfate IR absorbance with TBN, illustrate the invention.
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; andcorrelating 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−1.
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−1.
Patent Application
20070228281
