Determination of total base number in marine engine lubricants by elements

• US 20070196925A1
• Filed: 02/02/2007
• Published: 08/23/2007
• Est. Priority Date: 02/10/2006
• Status: Active Grant

• Current Assignee: ExxonMobil Research & Engineering Company (Exxon Mobil Corporation)
• Original Assignee: ExxonMobil Research & Engineering Company (Exxon Mobil Corporation)
• Inventors: Reischman, P.
• Granted Patent: US 7,741,122 B2
• Time in Patent Office: Days
• US Class Current: 436/60
• CPC Class Codes: G01N 33/287 Sulfur content
• CPC Class Codes: G01N 33/2876 Total acid number
• CPC Class Codes: Y10T 436/18 Sulfur containing

Abstract

The present invention provides a method for determining the TBN of a used lubricating oil by measuring with a single device at least one element, such as sulfur, and correlating the measured amount to the oil'"'"'s TBN. Preferably, a spectroscopic device is used to make the measurement.

Claims

1. A method for determining a used lubricating oil'"'"'s TBN comprising:

measuring with a single device the amount of at least sulfur in the used lubricating oil; and

,

correlating the measured amount to the TBN.

2. The method of claim 1 wherein the amount of sulfur is measured spectroscopically.

3. The method of claim 2 including spectroscopically measuring the amount of at least one other element selected from one which was present in the oil when unused and using that measurement as an internal reference.

4. The method of claim 2 or 3 wherein the spectroscopic method is selected from the group consisting of ICP-AES, RDE-AES and XRF.

5. The method of claim 3 wherein the amount of sulfur and at least one other element in the lubricating oil is measured by XRF.

6. The method of claim 3 or 5 wherein one other element is calcium.

7. The method of claim 3 including measuring at least one wear element.

8. A method for determining the TBN of a used marine lubricating oil comprising:

spectroscopically measuring the amount of at least sulfur in the oil; and

correlating the amount measured with the oil'"'"'s TBN.

9. The method of claim 8 including spectroscopically measuring the amount of at least one other element selected from those which were present in the oil when unused and using that measurement as an internal reference.

10. The method of claim 9 wherein the amount of sulfur and at least one other element is measured spectroscopically by a method selected from the group consisting of ICP-AES, RDE-AES and XRF.

11. The method of claim 9 wherein the one other element is calcium.

12. The method of claim 11 including spectroscopically measuring the amount of at least one wear element in the oil, thereby determining the oil'"'"'s TBN and the amount of at least one wear element with a single instrument.