Solid anti-friction devices – materials therefor – lubricant or se – Lubricants or separants for moving solid surfaces and... – Organic -co- compound
Reexamination Certificate
2000-10-26
2001-07-17
Medley, Margaret (Department: 1714)
Solid anti-friction devices, materials therefor, lubricant or se
Lubricants or separants for moving solid surfaces and...
Organic -co- compound
C508S583000, C508S584000, C508S586000, C508S460000
Reexamination Certificate
active
06262001
ABSTRACT:
BACKGROUND OF THE INVENTION
U.S. Pat. No. 3,036,971 discloses preparing detergent dispersant additives based on sulfurized alkylphenates of high basicity alkaline earth metals. These additives are prepared by sulfurization of an alkylphenol, neutralization of the sulfurized alkylphenol with an alkaline earth base, then super-alkalization by carbonation of the alkaline earth base dispersed in the sulfurized alkylphenate.
French patent 1,563,557 discloses detergent additives based on sulfurized calcium alkylsalicylates. These additives are prepared by carboxylation of a potassium alkylphenate, exchange with calcium chloride, then sulfurization of the calcium alkylsalicylate obtained with sulfur in the presence of lime, a carboxylic acid and an alkylene glycol or alkyl ether of alkylene glycol.
Applicants' French patent application 2,625,220 discloses superalkalized detergent-dispersant additives based on alkylphenates and alkylsalicylates. These additives are prepared by neutralization of an alkylphenol with an alkaline earth base in the presence of an acid and a solvent, distillation of the solvent, carboxylation, sulfurization and superalkalization by sulfur and an alkaline earth base in the presence of glycol and solvent, followed by carbonation and filtration.
Applicants' PCT patent application PCT/FR95/00299 discloses a process that is able to improve substantially the performance of these additives, particularly in the tests relating to foaming, compatibility and dispersion in a new oil, and in the tests of stability towards hydrolysis. This process comprises neutralization with alkaline earth base of a mixture of linear and branched alkylphenols in the presence of a carboxylic acid, carboxylation by the action of carbon dioxide of the alkylphenate, followed by sulfurization and superalkalization, then carbonation, distillation, filtration, and degassing in air.
SUMMARY OF THE INVENTION
The present invention provides a method for producing an unsulfurized, alkali metal-free, additive for lubricating oils. That method comprises the neutralization of alkylphenols using an alkaline earth base in the presence of at least one carboxylic acid containing from one to four carbon atoms, in the absence of alkali base, in the absence of dialcohol, and in the absence of monoalcohol; followed by carboxylation of the alkylphenate produced in the neutralization step and filtration of the product of the carboxylation step.
This unsulfurized, alkali metal-free, additive can be obtained by filtration of an intermediate in the process described in PCT patent application PCT/FR95/00299. That intermediate is formed by neutralization with alkaline earth base of a mixture of linear and branched alkylphenols in the presence of a carboxylic acid and carboxylation by the action of carbon dioxide of the alkylphenate. We have discovered that the subsequent steps of sulfurization and superalkalization are not needed to make an additive having improved antioxidant properties, high temperature deposit control, and black sludge deposit control.
The alkylphenols contain up to 85% of linear alkylphenol in mixture with at least 15% of branched alkylphenol in which the branched alkyl radical contains at least nine carbon atoms. Preferably, the alkylphenols contain from 35% to 85% of linear alkylphenol in mixture with from 15% to 65% of branched alkylphenol. The ratio of branched versus linear alkylphenol is given by weight. Preferably, the linear alkyl radical contains 12 to 40 carbon atoms, more preferably from 18 to 30 carbon atoms, and the branched alkyl radical contains at least 9 carbon atoms, preferably from 9 to 24 carbon atoms, more preferably 10 to 15 carbon atoms,
Preferably, alkaline earth base is selected from the group consisting of calcium oxide, calcium hydroxide, magnesium oxide, and mixtures thereof.
Preferably, the carboxylic acid is a mixture of formic acid and acetic acid, more preferably a 50/50 by weight mixture.
The neutralization operation is carried out at a temperature of at least 200° C., preferably at least 215° C. The pressure is reduced gradually below atmospheric in order to remove the water of reaction, in the absence of any solvent that may form an azeotrope with water. The quantities of reagents used correspond to the following molar ratios:
(1) alkaline earth base/alkylphenol of from 0.2:1 to 0.7:1, preferably from 0.3:1 to 0.5:1; and
(2) carboxylic acid/alkylphenol of from 0.01:1 to 0.5:1, preferably from 0.03:1 to 0.15:1.
In one embodiment, the neutralization step is carried out at a temperature of at least 240° C. with a gradual reduction in pressure below atmospheric so as to reach a pressure of no more than 7,000 Pa (70 mbars) at 240° C.
The alkylphenate obtained in the neutralization step is carboxylated in order to convert at least 20 mole % of the starting alkylphenols to alkylsalicylate using carbon dioxide under carboxylation conditions. Preferably, at least 22 mole % of the starting alkylphenols is converted, and this conversion occurs at a temperature between 180° C. and 240° C., under a pressure within the range of from above atmospheric pressure to 15×10
5
Pa (15 bars) for a period of one to eight hours.
Preferably, at least 25 mole % of the starting alkylphenols is converted to alkylsalicylate using carbon dioxide at a temperature equal to or greater than 200° C., under a pressure of 4×10
5
Pa (4 bars).
The product of the carboxylation step is then filtered to remove any sediment formed in the carboxylation step.
The detergent-dispersant produced by this method has the following composition:
(a) 40% to 60% alkylphenol,
(b) 10% to 40% alkaline earth alkylphenate, and
(c) 20% to 40% alkaline earth single aromatic-ring alkylsalicylate.
That detergent-dispersant composition may also comprise an alkaline earth double aromatic-ring alkylsalicylate, but the mole ratio of single aromatic-ring alkylsalicylate to double aromatic-ring alkylsalicylate will be at least 8:1.
That detergent-dispersant composition can be further characterized by the act that the ratio of infrared transmittance band for aromatic ring out of plane C-H bending at about 763±3 cm
−1
to infrared transmittance band for aromatic ring out of plane C-H bending at about 832±3 cm
−1
is less than 0.1:1.
The detergent-dispersant produced by the method of the present invention can be used in an engine lubricating composition containing a major part of lubricating oil, from 1% to 30% of the detergent-dispersant, and preferably at least one other additive. Examples of other additives that can be included in the concentrate include alkaline earth metal detergents, ashless dispersants, oxidation inhibitors, rust inhibitors, demulsifiers, extreme pressure agents, friction modifiers, multifunctional additives, viscosity index improvers, pour point depressants, and foam inhibitors.
In marine applications, the black sludge deposit control, high temperature deposit control, and demulsibility performance of a lubricating oil can be improved by adding to the lubricating oil an effective amount of this detergent-dispersant.
In automotive applications, the high temperature deposit control performance and oxidation inhibition performance of a lubricating oil can be improved by adding to the lubricating oil an effective amount of the detergent-dispersant of the present invention.
The invention also provides a hydraulic oil composition with improved filterability containing a base oil of lubricating viscosity, from 0.1% to 3% of the detergent-dispersant of the present invention, and preferably at least one other additive.
The invention also provides a concentrate comprising the detergent-dispersant of the present invention, an organic diluent, and preferably at least one other additive. The organic diluent constitutes from 20% to 80% of the concentrate.
DETAILED DESCRIPTION OF THE INVENTION
Prior to discussing the invention in further detail, the following terms will be defined:
DEFINITIONS
As used herein, the following terms have the following meanings, unless expressl
Cazin Jacques
Le Coent Jean-Louis Marie
Tequi Pierre
Chevron Chemical Company LLC
Medley Margaret
Stumpf Walter L.
Toomer Cephia D.
LandOfFree
Unsulfurized, alkali meta-free, additive for lubricating oils does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Unsulfurized, alkali meta-free, additive for lubricating oils, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Unsulfurized, alkali meta-free, additive for lubricating oils will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2450295