U.S. patent application number 11/567402 was filed with the patent office on 2007-05-10 for carboxylated detergent- disperant additive for lubricating oils.
This patent application is currently assigned to CHEVRON ORONITE COMPANY LLC. Invention is credited to Cornelis Hendrikus Maria Boons, Chettan Karsan, Eugene Spala, Willem Van Dam.
Application Number | 20070105730 11/567402 |
Document ID | / |
Family ID | 33418040 |
Filed Date | 2007-05-10 |
United States Patent
Application |
20070105730 |
Kind Code |
A1 |
Boons; Cornelis Hendrikus Maria ;
et al. |
May 10, 2007 |
CARBOXYLATED DETERGENT- DISPERANT ADDITIVE FOR LUBRICATING OILS
Abstract
The present invention provides a novel unsulfurized,
carboxylate-containing additive for lubricating oils, comprising a
mixture of alkaline earth metal salts (hydrocarbyl
phenate/hydrocarbyl salicylate) and a reduced amount of unreacted
hydrocarbyl phenols, as well as additive packages, concentrates and
finished oil compositions comprising the same. Specifically, it
relates to additives comprising said mixture in which said
hydrocarbyl salicylate is primarily single-aromatic-ring
hydrocarbyl salicylate. The invention also provides a method for
producing said additive.
Inventors: |
Boons; Cornelis Hendrikus
Maria; (Breda, NL) ; Spala; Eugene;
(Fairfield, CA) ; Van Dam; Willem; (Bergschenhoek,
NL) ; Karsan; Chettan; (Wembley, GB) |
Correspondence
Address: |
CHEVRON TEXACO CORPORATION
P.O. BOX 6006
SAN RAMON
CA
94583-0806
US
|
Assignee: |
CHEVRON ORONITE COMPANY LLC
6001 Bollinger Canyon Road
San Ramon
CA
94583-2324
CHEVRON ORONITE TECHNOLOGY B.V.
Petroleumweg 32 3196 KD Vondelingenplaat
Rotterdam
3196 KD
|
Family ID: |
33418040 |
Appl. No.: |
11/567402 |
Filed: |
December 6, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10444764 |
May 22, 2003 |
7163911 |
|
|
11567402 |
Dec 6, 2006 |
|
|
|
Current U.S.
Class: |
508/460 ;
508/518 |
Current CPC
Class: |
C10M 2207/027 20130101;
C10M 2215/28 20130101; C10M 159/22 20130101; C10M 2215/064
20130101; C10M 2207/144 20130101; C10M 2207/126 20130101; C10M
2223/045 20130101; C10N 2060/14 20130101; C10N 2030/43 20200501;
C10M 2223/047 20130101; C10N 2010/12 20130101; C10N 2030/42
20200501; C10N 2030/45 20200501; C10M 129/00 20130101; C10M
2207/023 20130101; C10N 2040/25 20130101; C10M 163/00 20130101;
C10N 2030/12 20130101; C10M 141/02 20130101; C10M 2207/026
20130101; C10M 2207/262 20130101; C10M 2207/023 20130101; C10M
2207/144 20130101; C10N 2010/04 20130101; C10M 2223/045 20130101;
C10N 2010/04 20130101; C10M 2207/023 20130101; C10M 2207/144
20130101; C10N 2010/04 20130101; C10M 2223/045 20130101; C10N
2010/04 20130101 |
Class at
Publication: |
508/460 ;
508/518 |
International
Class: |
C10M 159/22 20060101
C10M159/22 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 4, 2003 |
GB |
0318 222.7 |
Claims
1-41. (canceled)
42. A lubricating oil additive comprising: (a) from 0 to 35%
hydrocarbyl phenol; (b) from 10 to 50% alkaline earth metal
hydrocarbyl phenate; (c) from 15 to 60% alkaline earth metal
single-aromatic-ring hydrocarbyl salicylate; and (d) from 0% to 50%
organic diluent.
43. A lubricating oil additive according to claim 42 further
comprising an alkaline earth double-aromatic-ring hydrocarbyl
salicylate wherein the mole ratio of single-aromatic-ring
hydrocarbyl salicylate to double-aromatic-ring hydrocarbyl
salicylate is at least 8:1.
44. A lubricating oil composition comprising: (a) a major part of a
base oil of lubricating viscosity, (b) from 1% to 30% of the
lubricating oil additive according to claim 42.
45. A lubricating oil composition according to claim 44 further
comprising at least one of the following: (a) an ashless dispersant
(b) an oxidation inhibitor; (c) a rust inhibitor; (d) a
demulsifier; (e) an extreme pressure agent; (f) a friction
modifier; (g) a multifunctional additive; (h) a viscosity index
improver; (i) a pour point depressant; (j) a foam inhibitor; and
(k) a metal-containing detergent.
46. A hydraulic oil composition containing a major part of base oil
of lubricating viscosity and from 0.1 to 6.0% of the lubricating
oil additive according to claim 42.
47. A concentrate comprising: a) from 20 to 80% of an organic
diluent, and (b) the lubricating oil additive according to claim
42.
48. An additive package comprising the lubricating oil additive
according to claim 42 and further comprising at least one of the
following: (a) a metal-containing detergent (b) an ashless
dispersant (c) an oxidation inhibitor; (d) a rust inhibitor; (e) a
demulsifier; (f) an extreme pressure agent; (g) a friction
modifier; (h) a multifunctional additive; (i) a viscosity index
improver; (j) a pour point depressant; and (k) a foam
inhibitor.
49. A lubricant additive composition comprising the lubricating oil
additive of claim 42 and at least one of the following: (a) a
phenate; (b) a phenate-stearate; (c) a salicylate; and (d) a
carboxy-stearate.
50. The composition of claim 49 wherein the mass ratio of phenate
to said lubricating oil additive is from 1:0.035 to 1:98.
51. The composition of claim 49 wherein the mass ratio of phenate
to said lubricating oil additive is from 1:0.239 to 1:14.
52. The composition of claim 49 wherein the mass ratio of phenate
to said lubricating oil additive is from 1:0.451 to 1:7.5.
53. The composition of claim 49 wherein the mass ratio of
phenate-stearate to said lubricating oil additive is from 1:0.051
to 1:126.
54. The composition of claim 49 wherein the mass ratio of
phenate-stearate to said lubricating oil additive is from 1:0.353
to 1:18.
55. The composition of claim 49 wherein the mass ratio of
phenate-stearate to said lubricating oil additive is from 1:0.667
to 1:9.7.
56. The composition of claim 49 wherein said salicylate is a
medium-overbased salicylate.
57. The composition of claim 49 wherein said salicylate is a
high-overbased salicylate.
58. The composition of claim 57 wherein the mass ratio of
salicylate to said lubricating oil additive is from 1:0.026 to
1:120.
59. The composition of claim 57 wherein the mass ratio of
salicylate to said lubricating oil additive is from 1:0.178 to
1:17.
60. The composition of claim 57 wherein the mass ratio of
salicylate to said lubricating oil additive is from 1:0.335 to
1:9.2.
61. The composition of claim 49 wherein the mass ratio of
carboxy-stearate to said lubricating oil additive is from 1:0.023
to 1:105.
62. The composition of claim 49 wherein the mass ratio of
carboxy-stearate to said lubricating oil additive is from 1:0.156
to 1:15.
63. The composition of claim 49 wherein the mass ratio of
carboxy-stearate to said lubricating oil additive is from 1:0.294
to 1:8.1.
64. A method for improving corrosion protection in an internal
combustion engine, said method comprising operating an internal
combustion engine with the lubricating oil composition according to
claim 44.
65. A method for improving viscosity increase control of a
lubricating oil composition, said method comprising adding an
effective viscosity increase controlling amount of the lubricating
oil additive composition according to claim 42 to said lubricating
oil composition.
66. (canceled)
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a novel unsulfurized,
carboxylate-containing additive for lubricating oils, comprising a
mixture of alkaline earth metal salts (hydrocarbyl
phenate/hydrocarbyl salicylate) and a reduced amount of unreacted
hydrocarbyl phenols, as well as additive packages, concentrates and
finished oil compositions comprising the same. Specifically, it
relates to additives comprising said mixture in which said
hydrocarbyl salicylate is primarily single-aromatic-ring
hydrocarbyl salicylate. This additive improves antioxidant
properties, high temperature deposit control, BN retention,
corrosion control and black sludge control in lubricating oils.
This invention is also directed, in part, to methods of preparing
and using said novel additive.
BACKGROUND OF THE INVENTION
[0002] The preparation of hydrocarbyl phenates and hydrocarbyl
salicylates is well known in the art.
[0003] 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 metal base, then
super-alkalization by carbonation of the alkaline earth metal base
dispersed in the sulfurized alkylphenate.
[0004] 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
[0005] 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 metal base in the presence of
an acid and a solvent, distillation of the solvent, carboxylation,
sulfurization and superalkalization by sulfur and an alkaline earth
metal base in the presence of glycol and solvent, followed by
carbonation and filtration.
[0006] PCT Patent Application Publication No. WO 95/25155 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 metal 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 super-alkalization, then carbonation,
distillation, filtration, and degasing in air.
[0007] European Patent Application Publication No. 0933417
discloses an unsulfurized, alkali metal-free detergent-dispersant
additive, comprising a mixture of alkaline earth metal salts
(alkylphenate/alkylsalicylate) and unreacted alkylphenol. This
additive improves antioxidant propties, high temperature deposit
control, and black sludge control.
[0008] U.S. Pat. Nos. 6,162,770 and 6,262,001 teach an
unsulfurized, alkali metal-free, detergent-dispersant composition
having from 40% to 60% alkylphenol, from 10% to 40% alkaline earth
alkylphenate, and from 20% to 40% alkaline earth
single-aromatic-ring alkylsalicylate, and a process for preparing
the same. This composition may have an alkaline earth
double-aromatic-ring alkylsalicylate as long as the mole ratio of
single-ring alkylsalicylate to double-aromatic-ring alkylsalicylate
is at least 8:1. This composition may be produced by the three-step
process involving neutralization of alkylphenols, carboxylation of
the resulting alkylphenate, and filtration of the product of the
carboxylation step. The detergent-dispersant produced by the method
can be used in an engine lubricating composition to improve
antioxidant properties, high temperature deposit control, and black
sludge control.
SUMMARY OF THE INVENTION
[0009] The present invention provides a novel unsulfurized,
carboxylate-containing additive for lubricating oils, comprising a
mixture of alkaline earth metal salts (hydrocarbyl
phenate/hydrocarbyl salicylate) and a reduced amount of unreacted
hydrocarbyl phenols, as well as additive packages, concentrates and
finished oil compositions comprising the same. Specifically, it
relates to additives comprising said mixture in which said
hydrocarbyl salicylate is primarily single-aromatic-ring
hydrocarbyl salicylate.
[0010] The present invention also provides a method for producing
the above described additive, which comprises the neutralization of
hydrocarbyl phenol using an alkaline earth base in the presence of
a promoter to produce a hydrocarbyl phenate. Preferably, said
promoter comprises at least one carboxylic acid containing from one
to four carbon atoms, and said neutralization step is carried out
in the absence of alkali base, in the absence of dialcohol, and in
the absence of monoalcohol. The neutralization step is followed by
carboxylation of the hydrocarbyl phenate produced in the
neutralization step; and separation of the starting hydrocarbyl
phenols from the product of the carboxylation step.
[0011] The hydrocarbyl phenols may comprise a mixture of linear
and/or branched hydrocarbyl constituents. For example, the
hydrocarbyl phenols may be made up entirely of linear hydrocarbyl
phenol, entirely of branched hydrocarbyl phenol, or a mixture of
both. Preferably, the hydrocarbyl phenols contain up to 85% of
linear hydrocarbyl phenol in mixture with at least 15% of branched
hydrocarbyl phenol in which the branched hydrocarbyl radical
contains at least nine carbon atoms. More preferably, the
hydrocarbyl phenols are alkylphenols which 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 hydrocarbyl radical
contains 12 to 40 carbon atoms, more preferably from 18 to 30
carbon atoms, and, if branched hydrocarbyl phenols are present, the
branched hydrocarbyl radical contains at least 9 carbon atoms,
preferably from 9 to 24 carbon atoms, more preferably 10 to 15
carbon atoms.
[0012] Preferably, the alkaline earth base is selected from the
group consisting of calcium oxide, calcium hydroxide, magnesium
oxide, and mixtures thereof.
[0013] Preferably, the carboxylic acid is a mixture of formic acid
and acetic acid, more preferably a 50/50 by weight mixture of
formic and acetic acid.
[0014] Preferably, the neutralization step is carried out at a
temperature of at least 200.degree. C., more preferably at least
215.degree. 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. Preferably, the
quantities of reagents used correspond to the following molar
ratios: [0015] (1) alkaline earth base/alkylphenol of from 0.2:1 to
0.7:1, more preferably from 0.3:1 to 0.5:1; and [0016] (2)
carboxylic acid/alkylphenol of from 0.01:1 to 0.5:1, more
preferably from 0.03:1 to 0.15:1.
[0017] In one embodiment, the neutralization step is carried out at
a temperature of at least 240.degree. 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.degree. C.
[0018] The hydrocarbyl phenate obtained in the neutralization step
is carboxylated in order to convert at least 20 mole % of the
starting hydrocarbyl phenols to hydrocarbyl salicylate using carbon
dioxide under carboxylation conditions. Preferably, at least 22
mole % of the starting hydrocarbyl phenols is converted, and this
conversion occurs at a temperature between 180.degree. C. and
240.degree. C., under a pressure within the range of from above
atmospheric pressure to 15.times.10.sup.5 Pa (15 bars) for a period
of one to eight hours.
[0019] More preferably, the starting hydrocarbyl phenols are
alkylphenols and at least 25 mole % of the starting alkylphenols is
converted to alkylsalicylate using carbon dioxide at a temperature
equal to or greater than 200.degree. C., under a pressure of
4.times.10.sup.5 Pa (4 bars).
[0020] The hydrocarbyl salicylate produced in the carboxylation
step carboxylation step may comprise both single-aromatic-ring
hydrocarbyl salicylate and double-aromatic-ring hydrocarbyl
salicylate. Preferably, the mole ratio of single-aromatic-ring
hydrocarbyl salicylate to double-aromatic-ring hydrocarbyl
salicylate is at least 8:1.
[0021] Preferably, the product of the carboxylation step is then
filtered to remove any sediment formed in the carboxylation
step.
[0022] The product of the carboxylation step is then subjected to a
separation procedure such as solvent extraction, distillatioin,
membrane filtration, and the like wherein at least about 10% of the
starting hydrocarbyl phenols are separated from the product of the
carboxylation step. Preferably, at least about 30% to about 55% of
the starting hydrocarbyl phenols are separated. More preferably, at
least about 45% to about 50% of the starting hydrocarbyl phenols
are separated from the product of the carboxylation step.
[0023] Once the starting hydrocarbyl phenols are separated from the
product of the carboxylation step, said hydrocarbyl phenols may
advantageously be recycled to be used as starting materials in the
process of the present invention or in any other process.
[0024] Preferably, the separation step is performed via
distillation, more preferably via falling film distillation or
short path distillation, most preferably via wiped film evaporator
distillation. Said distillation is carried out at a temperature of
from about 150.degree. C. to about 250.degree. C. and at a pressure
of about 0.1 to about 4 mbar; more preferably from about
190.degree. C. to about 230.degree. C. and at about 0.5 to about 3
mbar; most preferably from about 195.degree. C. to about
225.degree. C. and at a pressure of about 1 to about 2 mbar.
[0025] The unsulfurized, carboxylate-containing additive of the
present invention may advantageously be blended with an effective
viscosity improving amount of organic diluent. Preferably, enough
diluent is added so that said diluent makes up from about 10% to
about 80% by weight of the blended product. More preferably, said
diluent makes up from about 20% to about 50% by weight of the
blended product. Suitable diluents include Group 1 or Group 2 base
oils such as 100N base oil; organic solvents such as pentane,
heptane, benzene, toluene and the like; and other suitable organic
compounds such as hydrocarbyl phenols which may advantageously be
recycled from the distillation step of the present invention.
[0026] The unsulfurized, carboxylate-containing additive produced
by this method has the following composition: [0027] (a) less than
40% hydrocarbyl phenol, [0028] (b) 10% to 50% alkaline earth metal
hydrocarbyl phenate, [0029] (c) 15% to 60% alkaline earth metal
single-aromatic-ring hydrocarbyl salicylate, and [0030] (d) 0% to
50% organic diluent.
[0031] In one embodiment, the unsulfurized carboxylate-containing
additive comprises from 0 to 35% hydrocarbyl phenol; preferably
from 0 to 30% hydrocarbyl phenol; more preferably from 0 to 20%
hydrocarbyl phenol; most preferably from 0 to 15%/1 hydrocarbyl
phenol.
[0032] The unsulfurized, carboxylate-containing additive may also
comprise an alkaline earth metal double-aromatic-ring hydrocarbyl
salicylate, but the mole ratio of single-aromatic-ring hydrocarbyl
salicylate to double-aromatic-ring hydrocarbyl salicylate will be
at least 8:1.
[0033] The unsulfurized, carboxylate-containing additive produced
by the method of the present invention can be used in an engine
lubricating oil composition containing a major part of lubricating
oil, from 1% to 30% of the unsulfurized, carboxylate-containing
additive of the present invention, and preferably at least one
other additive. Examples of other additives that may be used
include metal-containing detergents, ashless dispersants, oxidation
inhibitors, rust inhibitors, demulsifiers, extreme pressure agents,
friction modifiers, multifunctional additives, viscosity index
improvers, pour point depressants, and foam inhibitors.
[0034] The unsulfurized, carboxylate-containing additive produced
by the method of the present invention has been found to be
particularly useful when used in an engine lubricating oil
composition in combination with at least one of the following: a
phenate, a phenate-stearate, a salicylate, and a carboxy-stearate.
Preferably, the mass ratio of phenate to unsulfurized,
carboxylate-containing additive in said composition is from 1:0.035
to 1:98; more preferably from 1:0.239 to 1:14; most preferably from
1:0.451 to 1:7.5. Preferably, the mass ratio of phenate-stearate to
unsulfurized, carboxylate-containing additive in said composition
is from 1:0.051 to 1:126; more preferably from 1:0.353 to 1:12;
most preferably from 1:0.667 to 1:97. Preferably, the mass ratio of
salicylate to unsulfurized, carboxylate-containing additive in said
composition is from 1:0.026 to 1:120; more preferably from 1:0.178
to 1:17; most preferably from 1:0.335 to 1:9.2. Preferably, the
salicylate is a high-overbased salicylate. Preferably, the mass
ratio of carboxy-stearate to unsulfurized, carboxylate-containing
additive in said composition is from 1:0.023 to 1:105; more
preferably from 1:0.156 to 1:15; most preferably from 1:0.294 to
1:8.1.
[0035] In marine applications, the black sludge deposit control,
high temperature deposit control, viscosity increase control and
demulsibility performance of a lubricating oil can be improved by
adding to the lubricating oil an effective amount of the
unsulfurized, carboxylate-containing additive of the present
invention.
[0036] In automotive applications, the high temperature deposit
control performance, corrosion control and oxidation inhibition
performance of a lubricating oil can be improved by adding to the
lubricating oil an effective amount of the unsulfurized,
carboxylate-containing additive of the present invention.
[0037] The invention also provides a hydraulic oil composition with
improved filterability containing a base oil of lubricating
viscosity, from 0.1% to 6% of the unsulfurized,
carboxylate-containing additive of the present inventions, and
preferably at least one other additive,
[0038] The invention also provides a concentrate comprising the
unsulfurized, carboxylate-containing additive 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. Examples of other additives that may be used include
metal-containing detergents, ashless dispersants, oxidation
inhibitors, rust inhibitors, demulsifiers, extreme pressure agents,
friction modifiers, multifunctional additives, viscosity index
improvers, pour point depressants, and foam inhibitors.
DETAILED DESCRIPTION OF THE INVENTION
[0039] In its broadest aspect, the present invention provides an
unsulfurized, carboxylate-containing additive comprising
hydrocarbyl phenol, alkaline earth metal hydrocarbyl phenate, and
alkaline earth metal single-aromatic-ring hydrocarbyl salicylate
useful for improving BN retention, corrosion performance, bulk
oxidation, high temperature deposit control, black sludge control,
thermal oxidation stability, and other properties of a lubricating
oil.
[0040] Prior to discussing the invention in further detail, the
following terms will be defined:
Definitions
[0041] As used herein the following terms have the following
meanings unless expressly stated to the contrary:
[0042] The term "hydrocarbyl" means an alkyl or alkenyl group.
[0043] The term "metal" means alkali metals, alkaline earth metals,
or mixtures thereof.
[0044] The term "alkaline earth metal" means calcium, barium,
magnesium, strontium, or mixtures thereof.
[0045] The term "salicylate" means a metal salt of a salicylic
acid.
[0046] The term "alkaline earth metal single-aromatic-ring
hydrocarbyl salicylate" means an alkaline earth metal salt of a
hydrocarbyl salicylic acid, wherein there is only one hydrocarbyl
salicylic anion per each alkaline earth metal base cation.
[0047] The term "alkaline earth metal single-aromatic-ring
alkylsalicylate" means an alkaline earth metal single-aromatic-ring
hydrocarbyl salicylate wherein the hydrocarbyl group is an alkyl
group.
[0048] The term "alkaline earth metal double-aromatic-ring
hydrocarbyl salicylate" means an alkaline earth metal salt of a
hydrocarbyl salicylic acid, wherein there are two hydrocarbyl
salicylic anions per each alkaline earth metal base cation.
[0049] The term "alkaline earth metal double-aromatic-ring
alkylsalicylate" means an alkaline earth metal double-aromatic-ring
hydrocarbyl salicylate wherein the hydrocarbyl groups are alkyl
groups.
[0050] The term "hydrocarbyl phenol" means a phenol having one or
more hydrocarbyl substituents; at least one of which has a
sufficient number of carbon atoms to impart oil solubility to the
phenol.
[0051] The term "alkylphenol" means a phenol having one or more
alkyl substituents, wherein at least one of the alkyl substituents
has a sufficient number of carbon atoms to impart oil solubility to
the phenol.
[0052] The term "phenate" means a metal salt of a phenol.
[0053] The term "hydrocarbyl phenate" means a metal salt of a
hydrocarbyl phenol.
[0054] The term "alkaline earth metal hydrocarbyl phenate" means an
alkaline earth metal salt of a hydrocarbyl phenol.
[0055] The term "alkaline earth metal alkylphenate" means an
alkaline earth metal salt of an alkylphenol.
[0056] The term "phenate-stearate" means a phenate that has been
treated with stearic acid or anhydride or salt thereof.
[0057] The term "long-chain carboxylic acid" means a carboxylic
acid having an alkyl group having an average carbon number of from
13 to 28. The alkyl group may be linear, branched, or mixtures
thereof.
[0058] The term "carboxy-stearate" means an alkaline earth metal
single-aromatic-ring hydrocarbyl salicylate that has been treated
with a long-chain carboxylic acid, anhydride or salt thereof.
[0059] The term "Base Number" or "BN" refers to the amount of base
equivalent to milligrams of KOH in one gram of sample. Thus, higher
BN numbers reflect more alkaline products, and therefore a greater
alkalinity reserve. The BN of a sample can be determined by ASTM
Test No. D2896 or any other equivalent procedure.
[0060] Unless otherwise specified, all percentages are in weight
percent. ##STR1## single aromatic ring hydrocarbyl salicylate
##STR2## double aromatic ring hydrocarbyl salicylate Preparation of
the Lubricant Additive Composition A. Neutralization Step
[0061] In the first step, hydrocarbyl phenols are neutralized in
the presence of a promoter. In one embodiment, said hydrocarbyl
phenols are neutralized using an alkaline earth metal base in the
presence of at least one C.sub.1 to C.sub.4 carboxylic acid.
Preferably, this reaction is carried out in the absence of alkali
base, and in the absence of dialcohol or monoalcohol.
[0062] The hydrocarbyl phenols may contain up to 100% linear
hydrocarbyl groups, up to 100% branched hydrocarbyl groups, or both
linear and branched hydrocarbyl groups. Preferably, the linear
hydrocarbyl group, if present, is alkyl, and the linear alkyl
radical contains 12 to 40 carbon atoms, more preferably 18 to 30
carbon atoms. The branched hydrocarbyl radical, if present, is
preferably alkyl and contains at least nine carbon atoms,
preferably 9 to 24 carbon atoms, more preferably 10 to 15 carbon
atoms. In one embodiment, the hydrocarbyl phenols contain up to 85%
of linear hydrocarbyl phenol (preferably at least 35% linear
hydrocarbyl phenol) in mixture with at least 15% of branched
hydrocarbyl phenol.
[0063] The use of an alkylphenol containing at least 35% of
long-chain linear alkylphenol (from 18 to 30 carbon atoms) is
particularly attractive because a long linear alkyl chain promotes
the compatibility and solubility of the additives in lubricating
oils. However, the presence of relatively heavy linear alkyl
radicals in the alkylphenols can make the latter less reactive than
branched alkylphenols, hence the need to use harsher reaction
conditions to bring about their neutralization by an alkaline earth
metal base.
[0064] Branched alkylphenols can be obtained by reaction of phenol
with a branched olefin, generally originating from propylene. They
consist of a mixture of monosubstituted isomers, the great majority
of the substituents being in the para position, very few being in
the ortho position, and hardly any in the meta position. That makes
them relatively more reactive towards an alkaline earth metal base,
since the phenol function is practically devoid of steric
hindrance.
[0065] On the other hand, linear alkylphenols can be obtained by
reaction of phenol with a linear olefin, generally originating from
ethylene. They consist of a mixture of monosubstituted isomers in
which the proportion of linear alkyl substituents in the ortho,
para, and metal positions is more uniformly distributed. This makes
them less reactive towards an alkaline earth metal base since the
phenol function is less accessible due to considerable steric
hindrance, due to the presence of closer and generally heavier
alkyl substituents. Of course, linear alkylphenols may contain
alkyl substituents with some branching which increases the amount
of para substituents and, resultantly, increases the relative
reactivity towards alkaline earth metal bases.
[0066] The alkaline earth metal bases that can be used for carrying
out this step include the oxides or hydroxides of calcium,
magnesium, barium, or strontium, and particularly of calcium oxide,
calcium hydroxide, magnesium oxide, and mixtures thereof. In one
embodiment, slaked lime (calcium hydroxide) is preferred.
[0067] The promoter used in this step can be any material that
enhances neutralization. For example, the promoter may be a
polyhydric alcohol, dialcohol, monoalcohol, ethylene glycol or any
carboxylic acid. Preferably, a carboxylic acid is used. More
preferably, C.sub.1 to C.sub.4 carboxylic acids are used in this
step including, for example, formic, acetic, propionic and butyric
acid, and may be used alone or in mixture. Preferably, a mixture of
acids is used, most preferably a formic acid/acetic acid mixture.
The molar ratio of formic acid/acetic acid should be from 0.2:1 to
100:1, preferably between 0.5:1 and 4:1, and most preferably 1:1.
The carboxylic acids act as transfer agents, assisting the transfer
of the alkaline earth metal bases from a mineral reagent to an
organic reagent.
[0068] The neutralization operation is carried out at a temperature
of at least 200.degree. C., preferably at least 215.degree. C., and
more preferably at least 240.degree. C. The pressure is reduced
gradually below atmospheric in order to distill off the water of
reaction. Accordingly the neutralization should be conducted in the
absence of any solvent that may form an azeotrope with water.
Preferably, the pressure is reduced to no more than 7,000 Pa (70
mbars).
[0069] The quantities of reagents used should correspond to the
following molar ratios: [0070] (1) alkaline earth metal
base/hydrocarbyl phenol of 0.2:1 to 0.7:1, preferably 0.3:1 to
0.5:1; and [0071] (2) carboxylic acid/hydrocarbyl phenol of 0.01:1
to 0.5:1, preferably from 0.03:1 to 0.15:1.
[0072] Preferably, at the end of this neutralization step the
hydrocarbyl phenate obtained is kept for a period not exceeding
fifteen hours at a temperature of at least 215.degree. C. and at an
absolute pressure of between 5,000 and 10.sup.5 Pa (between 0.05
and 1.0 bar). More preferably, at the end of this neutralization
step the hydrocarbyl phenate obtained is kept for between two and
six hours at an absolute pressure of between 10,000 and 20,000 Pa
(between 0.1 and 0.2 bar).
[0073] By providing that operations are carried out at a
sufficiently high temperature and that the pressure in the reactor
is reduced gradually below atmospheric, the neutralization reaction
is carried out without the need to add a solvent that forms an
azeotrope with the water formed during this reaction.
B. Carboxylation Step
[0074] The carboxylation step is conducted by simply bubbling
carbon dioxide into the reaction medium originating from the
preceding neutralization step and is continued until at least 20
mole % of the starting hydrocarbyl phenols is converted to
hydrocarbyl salicylate (measured as salicylic acid by
potentiometric determination). It must take place under pressure in
order to avoid any decarboxylation of the alkylsalicylate that
forms.
[0075] Preferably, at least 22 mole % of the starting hydrocarbyl
phenols is converted to hydrocarbyl salicylate using carbon dioxide
at a temperature of between 180.degree. C. and 240.degree. C.,
under a pressure within the range of from above atmospheric
pressure to 15.times.10.sup.5 Pa (15 bars) for a period of one to
eight hours.
[0076] According to one variant, at least 25 mole % of the starting
hydrocarbyl phenols is converted to hydrocarbyl salicylate using
carbon dioxide at a temperature equal to or greater than
200.degree. C. under a pressure of 4.times.10.sup.5 Pa (4
bars).
C. Filtration Step
[0077] The product of the carboxylation step may advantageously be
filtered. The purpose of the filtration step is to remove
sediments, and particularly crystalline calcium carbonate, which
might have been formed during the preceding steps, and which may
cause plugging of filters installed in lubricating oil
circuits.
D. Separation Step
[0078] At least 10% of the starting hydrocarbyl phenol is separated
from the product of the carboxylation step. Preferably, the
separation is accomplished using distillation. More preferably, the
distillation is carried out in a wiped film evaporator at a
temperature of from about 150.degree. C. to about 250.degree. C.
and at a pressure of about 0.1 to about 4 mbar; more preferably
from about 190.degree. C. to about 230.degree. C. and at about 0.5
to about 3 mbar; most preferably from about 195.degree. C. to about
225.degree. C. and at a pressure of about 1 to about 2 mbar. At
least 10% of the starting hydrocarbyl phenol is separated. More
preferably, at least 30% of the starting hydrocarbyl phenol is
separated. Most preferably, up to 55% of the starting hydrocarbyl
phenol is separated. The separated hydrocarbyl phenol may then be
recycled to be used as starting materials in the novel process or
in any other process.
Unsulfurized, Carboxylate-Containing Additive
[0079] The unsulfurized, carboxylate-containing additive formed by
the present process can be characterized by its unique composition,
with much more alkaline earth metal single-aromatic-ring
hydrocarbyl salicylate and less hydrocarbyl phenol than produced by
other routes. When the hydrocarbyl group is an alkyl group, the
unsulfurized, carboxylate-containing additive has the following
composition; [0080] (a) less than 40% alkylphenol, [0081] (b) from
10% to 50% alkaline earth metal alkylphenate, and [0082] (b) from
15% to 60% alkaline earth metal single-aromatic-ring
alkylsalicylate.
[0083] Unlike alkaline earth metal alkylsalicylates produced by
other process, this unsulfurized, carboxylate-containing additive
composition can be characterized by having only minor amounts of an
alkaline earth metal double-aromatic-ring alkylsalicylates. The
mole ratio of single-aromatic-ring alkylsalicylate to
double-aromatic-ring alkylsalicylate is at least 8:1.
Characterization of the Product by Infrared Spectrometry
[0084] Out-of-aromatic-ring-plane C--H bending vibrations were used
to characterize the unsulfurized carboxylate-containing additive of
the present invention. Infrared spectra of aromatic rings show
strong out-of-plane C--H bending transmittance band in the 675-870
cm.sup.-1 region, the exact frequency depending upon the number and
location of substituents. For ortho-disubstituted compounds,
transmittance band occurs at 735-770 cm.sup.-1. For
para-disubstituted compounds, transmittance band occurs at 810-840
cm.sup.-1.
[0085] Infrared spectra of reference chemical structures relevant
to the present invention indicate that the out-of-plane C--H
bending transmittance band occurs at 750.+-.3 cm.sup.-1 for
ortho-alkylphenols, at 760.+-.2 cm.sup.-1 for salicylic acid, and
at 832.+-.3 cm.sup.-1 for para-alkylphenols.
[0086] Alkaline earth alkylphenates known in the art have infrared
out-of-plane C--H bending transmittance bands at 750.+-.3 cm.sup.-1
and at 832.+-.3 cm.sup.-1. Alkaline earth alkylsalicylates known in
the art have infrared out-of-plane C--H bending transmittance bands
at 763.+-.3 cm.sup.-1 and at 832.+-.3 cm.sup.-1.
[0087] The unsulfurized carboxylate-containing additive of the
present invention shows essentially no out-of-plane C--H bending
vibration at 763.+-.3 cm.sup.-1, even though there is other
evidence that alkylsalicylate is present. This particular
characteristic has not been fully explained. However, it may be
hypothesized that the particular structure of the single aromatic
ring alkylsalicylate prevents in some way this out-of-plane C--H
bending vibration. In this structure, the carboxylic acid function
is engaged in a cyclic structure, and thus may generate increased
steric hindrance in the vicinity of the aromatic ring, limiting the
free motion of the neighbor hydrogen atom. This hypothesis is
supported by the fact that the infrared spectrum of the acidified
product (in which the carboxylic acid function is no longer engaged
in a cyclic structure and thus can rotate) has an out-of-plane C--H
transmittance band at 763.+-.3 cm.sup.-1.
[0088] The unsulfurized carboxylate-containing additive of the
present invention can thus be characterized by having a ratio of
infrared transmittance band of out-of-plane C--H bending at about
763.+-.3 cm.sup.-1 to out-of-plane C--H bending at 832.+-.3
cm.sup.-1 of less than 0.1:1.
[0089] The unsulfurized, carboxylate-containing additive formed by
this method, being non-sulfurized, would provide improved high
temperature deposit control performance over sulfurized products.
Being alkali-metal free, this additive can be employed as a
detergent-dispersant in applications, such as marine engine oils,
where the presence of alkali metals have proven to have harmful
effects.
Detergents
[0090] The unsulfurized, carboxylate-containing additive formed by
the process described above has been found to provide improved bulk
oxidation and corrosion control performance when combined with
other additives, including detergents.
[0091] detergents help control varnish, ring zone deposits, and
rust by keeping insoluble particles in colloidal suspension.
Metal-containing (or ash-forming detergents) function both as
detergents to control deposits, and as acid neutralizers or rust
inhibitors, thereby reducing wear and corrosion and extending
engine life. Detergents generally comprise a polar head with a long
hydrophobic tail; with the polar head comprising a metal salt of an
acidic organic compound. The salts may contain a substantially
stoichiometric amount of the metal in which case they are usually
described as normal or neutral salts, and would typically have a
total base number (as measured by ASTM D2896) of from 0 to 10. It
is possible to include large amounts of a metal base by reacting an
excess of a metal compound such as an oxide or hydroxide with an
acidic gas such as carbon dioxide to form an overbased detergent.
Such overbased detergents may have a total base number of about 15
to 30 (low overbased); 31 to 170 (medium overbased); 171 to 400
(high overbased); or about 400 (high-high overbased).
[0092] Detergents that may be used include phenates, overbased
phenates and sulfurized phenates; phenate-carboxylates, and
overbased phenate-carboxylates; carboxy-stearates and overbased
carboxy-stearates; and low, medium and high overbased salicylates.
Suitable metals include the alkali or alkaline earth metals, e.g.,
sodium, potassium, lithium, calcium, and magnesium. The most
commonly used metals are calcium and magnesium, which may both be
present in detergents used in a lubricant.
Preparation of Phenates
[0093] The phenates which may be used in the present invention are
typically hydrocarbyl substituted phenates in which the hydrocarbyl
substituent or substituents of the phenate are preferably one or
more alkyl group, either branched or unbranched. Suitable alkyl
groups contain from 4 to 50, preferably from 9 to 28 carbon atoms.
Particularly suitable alkyl groups are C.sub.12 groups derivable
from propylene tetramer. The hydrocarbyl substituted phenates are
typically sulfurized.
[0094] According to one preferred embodiment of the present
invention, overbased sulfurized alkylphenates of alkaline earth
metals are prepared by neutralizing a sulfurized alkylphenol with
an alkaline earth base in the presence of a dilution oil, a glycol,
and halide ions, the glycol being present in the form of a mixture
with an alcohol having a boiling point above 150.degree. C.,
removing alcohol, glycol, water, and sediment, carbonating the
reaction medium with CO.sub.2 in the presence of halide ions, and
again removing alcohol, glycol, water, and sediment.
[0095] In another preferred embodiment, an overbased, sulfurized
hydrocarbyl phenate is prepared by a process comprising the steps
of: [0096] (a) neutralizing a sulfurized alkylphenol with an
alkaline earth base in the presence of a dilution oil, a glycol,
and halide ions, the glycol being present in the form of a mixture
with an alcohol having a boiling point above 150.degree. C.; [0097]
(b) removing alcohol, glycol, and water from the medium, preferably
by distillation; [0098] (c) removing sediment from the medium,
preferably by filtration; [0099] (d) carbonating the resultant
medium with CO.sub.2 in the presence of halide ions; and [0100] (e)
removing alcohol, glycol, and water from the medium, preferably by
distillation.
[0101] The alkaline earth bases useful in the above process include
the oxides and hydroxides of barium, strontium, and calcium,
particularly lime. Alcohols with a boiling point above 150.degree.
C. useful in the process include alcohols of C.sub.5 to C.sub.14
such as ethylhexanol, oxoalcohol, decylalcohol, tridecylalcohol;
alkoxyalcohols such as 2-butoxyethanol, 2-butoxypropanol; and
methyl ethers of dipropylene glycol. The amines useful in the
process include polyaminoalkanes, preferably polyaminoethanes,
particularly ethylenediamine, and aminoethers, particularly
tris(3-oxa-6-amino-hexyl)amine. The glycols useful in the process
include alkylene glycols, particularly ethylene glycol. The halide
ions employed in the process are preferably Cl.sup.- ions which may
be added in the form of ammonium chloride or metal chlorides such
as calcium chloride or zinc chloride.
[0102] The dilution oils suitable for use in the above process
include naphthenic oils and mixed oils and preferably paraffinic
oils such as neutral 100 oil. The quantity of dilution oil used is
such that the amount of oil in the final product constitutes from
about 25% to about 65% by weight of the final product, preferably
from about 30% to about 50%.
[0103] The process outlined above is more fully described in U.S.
Pat. No. 4,514,313, which is incorporated by reference into this
application.
Preparation of Phenate-Carboxylates
[0104] The phenate-carboxylates which may be used in the present
invention are typically hydrocarbyl substituted
phenate-carboxylates in which the hydrocarbyl substituent or
substituents of the phenate are preferably one or more alkyl group,
either branched or unbranched. Suitable alkyl groups contain from 4
to 50, preferably from 9 to 28 carbon atoms. Particularly suitable
alkyl groups are C.sub.12 groups derivable from propylene tetramer.
The hydrocarbyl substituted phenate-carboxylates may be sulfurized
or unsulfurized.
[0105] The overbased hydrocarbyl phenate-carboxylate is prepared
from an overbased hydrocarbyl phenate which has been treated,
either before, during, or subsequent to overbasing, with a
long-chain carboxylic acid (preferably stearic acid), anhydride or
salt thereof. That process comprises contacting a mixture of a
hydrocarbyl phenate, at least one solvent, metal hydroxide, aqueous
metal chloride, and an alkyl polyhydric alcohol containing from one
to five carbon atoms, with carbon dioxide under overbasing reaction
conditions. Using an aqueous metal chloride, instead of a solid
metal chloride, reduces the viscosity of the product. Preferably,
the metals are alkaline earth metals, most preferably calcium.
Preferably, the alkyl polyhydric alcohol is ethylene glycol.
[0106] In a preferred embodiment, the overbased hydrocarbyl
phenate-carboxylate is produced by overbasing a hydrocarbyl phenate
and treating the phenate (before, during, or after overbasing) with
a long-chain carboxylic acid (preferably stearic acid), anhydride
or salt thereof.
[0107] In the overbasing step, a mixture comprising hydrocarbyl
phenate (which can be sulfurized or unsulfurized), at least one
solvent, metal hydroxide, aqueous metal chloride, and an alkyl
polyhydric alcohol containing from one to five carbon atoms is
reacted with carbon dioxide under overbasing reaction conditions.
Overbasing reaction conditions include temperatures of from 250 to
375.degree. F. at approximately atmospheric pressure.
[0108] Preferably, the overbased hydrocarbyl phenate is a
sulfurized alkylphenate. Preferably, the metal is an alkaline earth
metal, more preferably calcium. Preferably, the alkyl polyhydric
alcohol is ethylene glycol.
[0109] The carboxylate treatment (treatment with long-chain
carboxylic acid, anhydride, or salt thereof) can occur before,
during, or after the overbasing step. It is unimportant when the
treatment with long-chain carboxylic acid, anhydride, or salt
thereof occurs relative to the overbasing step.
[0110] The phenate can be sulfurized or unsulfurized. Preferably,
the phenate is sulfurized. If the phenate is sulfurized, the
sulfurization step can occur anytime prior to overbasing. More
preferably, the phenate is sulfurized before the overbasing step
but after the carboxylate treatment.
[0111] The process outlined above is more fully described in U.S.
Pat. No. 5,942,476, which is incorporated by reference into this
application.
Preparation of Salicylates
[0112] The preparation of salicylates is well known in the art.
Preferred salicylates which may be used in the present invention
include medium and high overbased salicylates including salts of
polyvalent or monovalent metals, more preferably monovalent, most
preferably calcium. As used herein, medium overbased (MOB) is meant
to include salicylates with a TBN of about 31 to 170. High
overbased (HOB) is meant to include salicylates with a TBN from
about 171 to 400. High-hihg overbased (HHOB) is meant to include
salicylates with a TBN over 400.
[0113] In one embodiment, salicylates may be prepared, for
instance, starting from phenol, ortho-alkylphenol, or
para-alkylphenol, by alkylation, carboxylation and salt formation.
The alkylating agent preferably chosen is an olefin or a mixture of
olefins with more than 12 carbon atoms to the molecule.
Acid-activated clays are suitable catalysts for the alkylation of
phenol and ortho- and para- alkylphenol. The amount of catalyst
employed is, in general, 1-10 wt %, in particular, 3-7 wt %,
referred to the sum of the amounts by weight of alkylating agent
and phenol to be alkylated. The alkylation may be carried out at
temperatures between 100 and 250.degree. C., in particular, between
125 and 225.degree. C.
[0114] The alkylphenols prepared via the phenol or ortho- or
para-alkylphenol route may be converted into the corresponding
alkylsalicylic acids by techniques well known in the art. For
instance, the alkylphenols are converted with the aid of an
alcoholic caustic solution into the corresponding alkylphenates and
the latter are treated with CO.sub.2 at about 140.degree. C. and a
pressure of 10 to 30 atmospheres. From the alkylsalicylates so
obtained, the alkylsalicylic acids may be liberated with the aid
of, for example, 30% sulfuric acid.
[0115] For the preparation of overbased salicylates, the
alkylsalicyclic acids may be treated with an excess amount of a
metal compound, for instance, calcium in the form of
Ca(OH).sub.2.
[0116] For example, the alkylsalicylic acids may be treated with 4
equivalents of calcium in the form of Ca(OH).sub.2 with
introduction of 1.6 equivalents of CO.sub.2.
[0117] The preparation of medium and overbased salicylates is more
fully described in U.S. Pat. No. 4,810,398, and GB Patents
1,146,925; 790,473; and 786,167, which are incorporated by
reference into this application.
Preparation of Carboxy-Stearates
[0118] The carboxy-stearates which may be used in the present
invention are typically alkaline earth metal single-aromatic-ring
hydrocarbyl salicylates that have been treated with a long-chain
carboxylic acid, anhydride or salt thereof.
[0119] The carboxy-stearate is prepared from a mixture of alkaline
earth metal single-aromatic-ring salicylate, at least one solvent,
and alkaline earth metal hydroxide. The mixture is overbased by
contacting the mixture with carbon dioxide in the presence of an
alkyl polyhydric alcohol, wherein the alkyl group of the alcohol
has from one to five carbon atoms. One such useful alkyl polyhydric
alcohol is ethylene glycol.
[0120] The process outlined above is more fully described in U.S.
Pat. No. 6,348,438, which is incorporated by reference into this
application.
Base Oil of Lubricating Viscosity
[0121] The base oil of lubricating viscosity used in such
compositions may be mineral oil or synthetic oils of viscosity
suitable for use in the crankcase of an internal combustion engine.
Crankcase base oils ordinarily have a viscosity of about 1300 cSt
at 0.degree. F. (-18.degree. C.) to 3 cSt at 210.degree. F.
(99.degree. C.). The base oils may be derived from synthetic or
natural sources. Mineral oil for use as the base oil in this
invention includes paraffinic, naphthenic and other oils that are
ordinarily used in lubricating oil compositions. Synthetic oils
include both hydrocarbon synthetic oils and synthetic esters.
Useful synthetic hydrocarbon oils include liquid polymers of alpha
olefins having the proper viscosity. Especially useful are the
hydrogenated liquid oligomers of C.sub.6 to C.sub.12 alpha olefins
such as 1-decene trimer. Likewise, alkyl benzenes of proper
viscosity, such as didodecyl benzene, can be used. Useful synthetic
esters include the esters of monocarboxylic acids and
poolycarboxylic acids, as well as mono-hydroxy alkanols and
polyols. Typical examples are didodecyl adipate, pentaerythritol
tetracaproate, di-2-ethylhexyl adipate, dilaurylsebacate, and the
like. Complex esters prepared from mixtures of mono and
dicarboxylic acids and mono and dihydroxy alkanols can also be
used.
[0122] Blends of mineral oils with synthetic oils are also useful.
For example, blends of 10 to 25% hydrogenated 1-decene trimer with
75 to 90% 150 SUS (100.degree. F.) mineral oil make excellent
lubricating oil bases.
Other Additive Components
[0123] The following additive components are examples of some
components that can be favorably employed in the present invention.
These examples of additives are provided to illustrate the present
invention, but they are not intended to limit it: [0124] (1)
Ashless dispersants: alkenyl succinimides, alkenyl succinimides
modified with other organic compounds, and alkenyl succinimides
modified with boric acid, alkenyl succinic ester. [0125] (2)
Oxidation inhibitors: [0126] (a) Phenol type oxidation inhibitors:
4,4'-methylene bis(2,6-di-tert-butylphenol),
4,4'-bis(2,6-di-tert-butylphenol),
4,4'-bis(2-methyl-6-tert-butylphenol), 2,2'-methylene
bis(4-methyl-6-tert-butyl-phenol),
4,4'-butylidenebis(3-methyl-6-tert-butylphenol),
4,4'-isopropyl-idenebis(2,6-di-tert-butylphenol),
2,2'-methylene-bis(4-methyl-6-nonylphenol),
2,2'-isobutylidene-bis(4,6dimethyl-phenol),
2,2'-methylenebis(4-methyl-6-cyclohexylphenol),
2,6-di-tert-butyl4-methyl-phenol, 2,6-di-tert-butyl4-ethylphenol,
2,4-dimethyl-6-tert-butyl-phenol,
2,6-di-tert-4-(N,N'-dimethyl-aminomethylphenol),
4,4'-thiobis(2-methyl-6-tert-butylphenol),
2,2'-thiobis(4-methyl-6-tert-butylphenol),
bis(3-methyl4-hydroxy-5-tert-butylbenzylysulfide, and bis
(3,5-di-tert-butyl4-hydroxybenzyl). [0127] (b) Diphenylamine type
oxidation inhibitor: alkylated diphenylamine,
phenyl-alpha-naphthylamine, and alkylated .alpha.-naphthylamine.
[0128] (c) Other types: metal dithiocarbamate (e.g., zinc
dithiocarbamate), molybdenum oxysulfide succinimide complexes, and
methylenebis (dibutyl-dithiocarbamate). [0129] (3) Rust inhibitors
(Anti-rust agents) [0130] (a) Nonionic polyoxyethylene surface
active agents: polyoxyethylene lauryl ether, polyoxyethylene higher
alcohol ether, polyoxyethylene nonylphenyl ether, polyoxyethylene
octylphenyl ether, polyoxyethylene octyl stearyl ether,
polyoxyethylene oleyl ether, polyoxyethylene sorbitol monostearate,
polyoxyethylene sorbitol mono-oleate, and polethylene glcol
monooleate. [0131] (b) Other compounds: stearic acid and other
fatty acids, dicarboxilic acids, metal soaps, fatty acid amine
salts, metal aalts of heavy sulfonic acid, partial carboxylic acid
ester of polyhydric alcohol, and phosphoric ester. [0132] (4)
Demulsifiers: addition product of alkylphenol and ethyleneoxide,
poloxyethylene alkyl ether, and polyoxyethylene sorbitan ester.
[0133] (5) Extreme pressure agents (EP agents): zinc
dialkyldithiophosphate (aryl zinc, primary alkyl, and secondary
alkyl type), sulfurized oils, diphenyl sulfide, methyl
trichlorostearate, chlorinated naphthalene,
fluoroalkylpolysiloxane, and lead naphthenate. [0134] (6) Friction
modifiers: fatty alcohol, fatty acid, amine, borated ester, and
other esters. [0135] (7) Multifunctional additives; sulfurized
oxymolybdenum dithiocarbamate, sulfurized oxymolybdenum organo
phosphoro dithioate, oxymolybdenum monoglyceride, oxymolybdenum
diethylate amide, amine-molybdenum complex compound, and
sulfur-containing molybdenym complex compound. [0136] (8) Viscosity
index improvers: polymethacrylate type polymers, ethylene-propylene
copolymers, styrene-isoprene copolymers, hydrated styrene-isoprene
copolymers, polyisobutylene, and dispersant type viscosity index
improvers. [0137] (9) Pour point depressants: polymethyl
methacrylate. [0138] (10) Foam Inhibitors: alkyl methacrylate
polymers and dimethyl silicone polymers. [0139] (11) Metal
detergents: sulfurized or unsulfurized alkyl or alkenyl phenates,
alkyl or alkenyl aromatic sulfonates, sulfurized or unsulfurized
metal salts of multi-hydroxy alkyl or alkenyl aromatic compounds,
alkyl or alkenyl hydroxy aromatic sulfonates, sulfurized or
unsulfurized alkyl or alkenyl naphthenates, metal salts of alkanoic
acids, metal salts of an alkyl or alkenyl multiacid, and chemical
and physical mixtures thereof. Lubricating Oil Composition
[0140] The unsulfurized, carboxylate-containing additive produced
by the process of this invention is useful for imparting detergency
to an engine lubricating oil composition. Such a lubricating oil
composition comprises a major part of a base oil of lubricating
viscosity and an effective amount of the unsulfurized,
carboxylate-containing additive of the present invention, typically
from about 1% to about 30% by weight, based on the total weight of
the lubricating oil composition.
[0141] Adding an effective amount the unsulfurized,
carboxylate-containing additive of the present invention to a
lubricating oil improves the detergency of that lubricating oil in
automotive diesel and gasoline engines, as well as in marine engine
applications. Such compositions are frequently used in combination
with Group II metal detergents, and other additives.
[0142] Lubricating marine engines with an effective amount of
lubricating oil having the unsulfurized, carboxylate-containing
additive of the present invention can control black sludge
deposits. It also improves the high temperature deposit control
performance and demulsibility performance of that lubricating oil
in marine applications.
[0143] Adding an effective amount of the unsulfurized,
carboxylate-containing additive of the present invention to a
lubricating oil improves the high temperature deposit control
performance, corrosion control and the oxidation inhibition
performance of that lubricating oil in automotive applications.
[0144] In one embodiment, an engine lubricating oil composition
would contain [0145] (a) a major part of a base oil of lubricating
viscosity; [0146] (b) 1% to 30% of the unsulfurized,
carboxylate-containing additive of the present invention; [0147]
(c) 0% to 20% of at least one ashless dispersant; [0148] (d) 0% to
5% of at least one zinc dithiophosphate; [0149] (e) 0% to 10% of at
least one oxidation inhibitor; [0150] (f) 0% to 1% of at least one
foam inhibitor; and [0151] (g) 0% to 20% of at least one viscosity
index improver.
[0152] In another embodiment, an engine lubricating oil composition
would contain the above components and from 0% to 30% of a
metal-containing detergent.
[0153] In a further embodiment, an engine lubricating oil
composition is produced by blending a mixture of the above
components. The lubricating oil composition produced by that method
might have a slightly different composition than the initial
mixture, because the components may interact. The components can be
blended in any order and can be blended as combinations of
components.
Hydraulic Oil Composition
[0154] A hydraulic oil composition having improved filterability
can be formed containing a major part of a base oil of lubricating
viscosity, from 0.1% to 6% by weight of the unsulfurized,
carboxylate-containing additive of the present invention, and
preferably at least one other additive.
Additive Concentrates
[0155] Additive concentrates are also included within the scope of
this invention. The concentrates of this invention comprise the
compounds or compound mixtures of the present invention, with at
least one of the additives disclosed above. Typically, the
concentrates contain sufficient organic diluent to make them easy
to handle during shipping and storage.
[0156] From 20% to 80% of the concentrate is organic diluent. From
0.5% to 80% of the concentrate is the unsulfurized,
carboxylate-containing additive of the present invention. The
unsulfurized, carboxylate-containing additive contains the
single-aromatic-ring hydrocarbyl salicylate, and possibly
hydrocarbyl phenol and hydrocarbyl phenate. The remainder of the
concentrate consists of other additives.
[0157] Suitable organic diluents that can be used include mineral
oil or synthetic oils, as described above in the section entitled
"Base Oil of Lubricating Viscosity." The organic diluent preferably
has a viscosity of from about 1 to about 20 cSt at 100.degree.
C.
Examples of Additive Packages
[0158] Below are representative examples of additive packages that
can be used in a variety of applications. These representative
examples employ the unsulfurized, carboxylate-containing additive
of the present invention. The unsulfurized, carboxylate-containing
additive contains the single-aromatic-ring hydrocarbyl salicylate,
and possibly hydrocarbyl phenol and hydrocarbyl phenate. The
unsulfurized, carboxylate-containing additive may be used either
with or without other metal-containing detergents, depending upon
the desired BN of the final product. The following percentages are
based on the amount of active component, with neither process oil
nor diluent oil, but including sufficient metal-containing
detergents (including other types of metal detergents) to achieve
the desired BN. These examples are provided to illustrate the
present invention, but they are not intended to limit it.
TABLE-US-00001 I. Marine Diesel Engine Oils 1) Unsulfurized,
carboxylate-containing additive 65% Primary alkyl zinc
dithiophosphate 5% Oil of lubricating viscosity 30% 2)
Unsulfurized, carboxylate-containing additive 65% Alkenyl
succinimide ashless dispersant 5% Oil of lubricating viscosity 30%
3) Unsulfurized, carboxylate-containing additive 60% Primary alkyl
zinc dithiophosphate 5% Alkenyl succinimide ashless dispersant 5%
Oil of lubricating viscosity 30% 4) Unsulfurized,
carboxylate-containing additive 65% Phenol type oxidation inhibitor
10% Oil of lubricating viscosity 25% 5) Unsulfurized,
carboxylate-containing additive 55% Alkylated diphenylamine-type
oxidation inhibitor 15% Oil of lubricating viscosity 30% 6)
Unsulfurized, carboxylate-containing additive 65% Phenol-type
oxidation inhibitor 5% Alkylated diphenylamine-type oxidation
inhibitor 5% Oil of lubricating viscosity 25% 7) Unsulfurized,
carboxylate-containing additive 60% Primary alkyl zinc
dithiophosphate 5% Phenol-type oxidation inhibitor 5% Oil of
lubricating viscosity 30% 8) Unsulfurized, carboxylate-containing
additive 60% Alkenyl succinimide ashless dispersant 5% Alkylated
diphenylamine-type oxidation inhibitor 10% Oil of lubricating
viscosity 25% 9) Unsulfurized, carboxylate-containing additive 55%
Other additives 25% Primary alkyl zinc dithiophosphate Alkenyl
succinic ester ashless dispersant Phenol-type oxidation inhibitor
Alkylated diphenylamine-type oxidation inhibitor Oil of lubricating
viscosity 30%
[0159] TABLE-US-00002 II. Motor Car Engine Oils 1) Unsulfurized,
carboxylate-containing additive 25% Alkenyl succinimide ashless
dispersant 35% Primary alkyl zinc dithiophosphate 10% Oil of
lubricating viscosity 30% 2) Unsulfurized, carboxylate-containing
additive 20% Alkenyl succinimide ashless dispersant 40% Secondary
alkyl zinc dithiophosphate 5% Dithiocarbamate type oxidation
inhibitor 5% Oil of lubricating viscosity 30% 3) Unsulfurized,
carboxylate-containing additive 20% Alkenyl succinimide ashless
dispersant 35% Secondary alkyl zinc dithiophosphate 5% Phenol type
oxidation inhibitor 5% Oil of lubricating viscosity 35% 4)
Unsulfurized, carboxylate-containing additive 20% Alkenyl
succinimide ashless dispersant 30% Secondary alkyl zinc
dithiophosphate 5% Dithiocarbamate type anti-wear agent 5% Oil of
lubricating viscosity 40% 5) Unsulfurized, carboxylate-containing
additive 20% Succinimide ashless dispersant 30% Secondary alkyl
zinc dithiophosphate 5% Molybdenum-containing anti-wear agent 5%
Oil of lubricating viscosity 40% 6) Unsulfurized,
carboxylate-containing additive 20% Alkenyl succinimide ashless
dispersant 30% Other additives 10% Primary alkyl zinc
dithiophosphate Secondary alkyl zinc dithiophosphate Alkylated
diphenylamine-type oxidation inhibitor Dithiocarbamate type
anti-wear agent Oil of lubricating viscosity 40% 7) Unsulfurized,
carboxylate-containing additive 60% Other additives 10% Phenol type
oxidation inhibitor Alkylated diphenylamine-type Oxidation
inhibitor Dithiocarbamate type anti-wear agent Demulsifier
Boron-containing friction modifier Oil of lubricating viscosity
30%
[0160] TABLE-US-00003 III. Hydraulic Oils 1) Unsulfurized,
carboxylate-containing additive 20% Primary alkyl zinc
dithiophosphate 50% Other additives 25% Phenol type oxidation
inhibitor Phosphorus-containing extreme pressure agent Triazol type
corrosion inhibitor Demulsifier Nonionic anti-rust agent Oil of
lubricating viscosity 5% 2) Unsulfurized, carboxylate-containing
additive 10% Primary alkyl zinc dithiophosphate 40% Other additives
47% Phenol type oxidation inhibitor Sulfur-containing extreme
pressure agent Triazol type corrosion inhibitor Demulsifier
Nonionic anti-rust agent Oil of lubricating viscosity 3% 3)
Unsulfurized, carboxylate-containing additive 10%
Phosphorus-containing extreme pressure agent 40% Phenol type
oxidation inhibitor 15% Other additives 25% Diphenylamine type
oxidation inhibitor Sulfur-containing extreme pressure agent
Triazol type corrosion inhibitor Demulsifier Nonionic anti-rust
agent Oil of lubricating viscosity 10% 4) Unsulfurized,
carboxylate-containing additive 20% Phosphorus-containing extreme
pressure agent 30% Other additives 45% Diphenylamine type oxidation
inhibitor Sulfur-containing extreme pressure agent Triazol type
corrosion inhibitor Demulsifier Nonionic anti-rust agent Oil of
lubricating viscosity 5%
[0161] TABLE-US-00004 IV. Transmission Hydraulic Fluids 1)
Unsulfurized, carboxylate-containing additive 35% Primary alkyl
zinc dithiophosphate 20% Polyol type friction modifier 20%
Sulfur-containing extreme pressure agent 5% Oil of lubricating
viscosity 20% 2) Unsulfurized, carboxylate-containing additive 40%
Primary alkyl zinc dithiophosphate 15% Amide type friction modifier
15% Sulfur-containing extreme pressure agent 5% Oil of lubricating
viscosity 25% 3) Unsulfurized, carboxylate-containing additive 30%
Primary alkyl zinc dithiophosphate 20% Other additives 30% Alkenyl
succinimide ashless dispersant Amide type friction modifier Ester
type friction modifier Phosphorus, Sulfur-containing extreme
pressure agent Oil of lubricating viscosity 20% 4) Unsulfurized,
carboxylate-containing additive 35% Primary alkyl zinc
dithiophosphate 15% Other additives 25% Polyol type friction
modifier Amide type friction modifier Phosphorus, Sulfur-containing
extreme pressure agent Oil of lubricating viscosity 25%
EXAMPLES
[0162] The invention will be further illustrated by following
examples, which set forth particularly advantageous method
embodiments. While the Examples are provided to illustrate the
present invention, they are not intended to limit it.
Example 1
Preparation of the Novel Unsulfurized, Carboxylate-Containing
Additive
[0163] An intermediate product was prepared according to the
procedure given in U.S. Pat. No. 6,162,770, Example 1. Said
procedure is reproduced here:
A. Neutralization
[0164] A charge of 875 g of branched dodecylphenol (DDP) having a
molecular mass of 270, (i.e. 3.24 moles) and 875 g of linear
alkylphenol having a molecular mass of about 390 (i.e. 2.24 moles)
was placed in a four-necked 4 liter glass reactor above which was a
heat-insulated Vigreux fractionating column. The isomeric molar
repartition of para versus ortho alkylphenol was:
[0165] DDP: 89% para and 5.5% ortho
[0166] Linear alkylphenol: 39% para and 53% ortho.
[0167] The agitator was started up and the reaction mixture was
heated to 65.degree. C., at which temperature 158 grams of slaked
lime Ca(OH).sub.2 (i.e. 2.135 moles) and 19 g of a mixture (50/50
by weight) of formic acid and acetic acid were added.
[0168] The reaction medium underwent further heating to 120.degree.
C. at which temperature the reactor was placed under a nitrogen
atmosphere, then heated up to 165.degree. C. and then the nitrogen
introduction was stopped. Distillation of water commenced at this
temperature.
[0169] The temperature was increased to 240.degree. C. and the
pressure was reduced gradually below atmospheric until an absolute
pressure of 5,000 Pa (50 mbars) was obtained.
[0170] The reaction mixture was kept for five hours under the
preceding conditions. The reaction mixture was allowed to cool to
180.degree. C., then the vacuum was broken under a nitrogen
atmosphere and a sample was taken for analysis. The total quality
of distillate obtained was about 120 cm.sup.3; demixing took place
in the lower phase (66 cm.sup.3 being water).
B. Carboxylation:
[0171] The product obtained in Step (A) was transferred to a
3.6-liter autoclave and heated to 180.degree. C.
[0172] At this temperature, scavenging of the reactor with carbon
dioxide (CO.sub.2) was commenced and continued for ten minutes. The
amount of CO.sub.2 used in this step was in the order of 20
grams.
[0173] After the temperature had been raised to 200.degree. C., the
autoclave was closed, leaving a very small leak, and the
introduction of CO.sub.2 was continued so as to maintain a pressure
of 3.5.times.10.sup.5 Pa (3.5 bars) for 5 hours at 200.degree. C.
The amount of CO.sub.2 introduced was in the order of 50 grams.
After the autoclave had been cooled to 165.degree. C., the pressure
was restored to atmospheric and the reactor was then purged with
nitrogen.
[0174] A total quality of 1,912 grams of product was recovered
prior to filtration. The product was then filtered.
[0175] The above procedure was scaled up to a 6000 gallon reactor
and used to prepare the intermediate product. The intermediate
product was then subjected to the additional step of distillation
outlined below.
[0176] Analytical results for the intermediate product from the
6000 gallon batc were as follows: TABLE-US-00005 TBN 116 mg KOH/gm
Calcium 4.1 wt % Salicylic Acid Index (SAI) 40 mg KOH/gm
[0177] SAI is a measure of the quantity of alkylsalicylate formed
in the detergent-dispersant. It was determined by acidification of
the product by a strong acid (hydrochloric acid) in the presence of
diethyl ether, followed by a photentiometric titration on the
organic fraction (tetra n-butyl ammonium hydroxide was used as a
titration agent). Results are expressed in equivalent mg KOH per
gram of product (Base Number unit).
[0178] Distillation:
[0179] The intermediate product was fed at a rate of 70 kg/hr to a
wiped film evaporator (WFE) which had a surface area of 0.39
m.sup.2. The WFE had an internal condenser and entrainment
separator along with a hot oil jacket. The hot oil temperature in
the jacket was about 250.degree. C. The pressure within the WFE was
1.3 mbar. The feed temperature to the WFE was 135.degree. C. Final
product temperature exiting the WFE was 222.degree. C. The product
was cooled to less than 100.degree. C. before dilluting with 100N
base oil. Approximately 47.5% (by weight) of the feed to the WFE
was collected as distillate. The amount of distillate collected may
vary from 10% up to about 55% by weight of the feed to the WFE.
Depending upon the level of distillation, enough organic dilluent
is then added to the distilled product to give a manageable
viscosity. As the weight percentage of feed collected as distillate
increases, the amount of diluent needed to be added to the
distilled product in order to give a manageable viscosity
increases.
[0180] Analytical results for the distilled product were as
follows: TABLE-US-00006 TBN 174 mg KOH/gm Ca 6.09 wt % Salicylic
Acid Index (SAI) 58 Viscosity at 100.degree. C. 705 cSt Oil Content
(by mass balance) 21.5 wt %
[0181] It is well known in the art that salicylate structures are
thermally unstable. As the distilled material had a comparable
Salicylic-Acid index to calcium ratio as the feedstock, no
decomposition of the salicylate structure occurred even though the
feed was exposed to relatively high temperatures. No decomposition
occurred as the reduction time in the WFE is relatively short.
[0182] The distillate appearance was clear and slightly yellow
which is comparable to the appearance of the starting hydrocarbyl
phenols introduced in the neutralization step. The TBN content of
the distillate was essentially zero indicating than none of the
feedstock to the distillation step carried over into the
distillate. The distillate was analyzed by gas chromatography and
found to contain approximately 61% branched hydrocarbyl phenol, 39%
linear hydrocarbyl phenol, and 6% 100N base oil.
Example 2
[0183] The pre-distillation product prepared according to Example 1
was distilled under various conditions in the WFE described above.
Typical results for other distillation conditions are shown in
Table 1. TABLE-US-00007 TABLE 1 1 2 WFE Conditions: Feed Rate
(kg/hr) 122 86 Pressure (mbar) 1.44 1.5 Hot Oil Temp (.degree. C.)
235 254 Product Temperature Exiting 205 222 Evaporator (.degree.
C.) Amount of Distillate (wt %).sup.1 30 43 Oil in Final Product
(wt %) 0 14.5 Product Analytical Results TBN (mg KOH/gm) 166 174 Ca
(wt %) 5.92 6.2 SAI (mg KOH/gm) 57 59 Viscosity @ 100.degree. C.
(cSt) 226 575 Compostion of Distillate Branched Alkylphenol (wt %)
76 64 Linear Alkylphenol (wt %) 15 27 100N Base Oil (wt %) 9 9
.sup.1Based on WFE Feed Rate
Example 3
[0184] Example 1 was repeated except for the following changes:
[0185] a) The WFE had a surface area of 0.78 m.sup.2 [0186] b) The
feed rate to the WFE was about 135 kg/hr [0187] c) The final
distilled product was diluted with about 36 wt % 100N oil to
produce a product with a manageable viscosity.
[0188] Similar to Example 1, about 46% (based on weight) of the
feed to the evaporator was collected as distillate.
[0189] Analytical results for this product are as follows:
TABLE-US-00008 TBN 138 mg KOH/gm Calcium 4.96 wt % SAI 47 mg
KOH/gm
[0190] Dialysis was performed on about 15 gm of product from
Example 3 using a Soxhlet extraction apparatus (pentane solvent)
and a Latex membrane condom for about 24 hours to afford a
dialysate fraction (the material that passes through the membrane)
and a residue fraction (the material left in the latex membrane
bag).
[0191] The dialysate fraction from the dialysis procedure was
separated into two fractions using silica gel chromatography
(0.2-0.25 gm on two Silica Gel Cartridges--Waters Part No. 051900)
first using 12 ml of hexane to yield Fraction 1 followed by
reversing the Cartridges and flushing with 12 ml of 80:20 Ethyl
Acetate: Ethanol to afford Fraction 2. Fraction 1 was comprised of
diluent oil and Fraction 2 was comprised of free alkylphenols.
[0192] The Fraction 2 obtained from the chromatographic separation
procedure was analyzed using supercritical chromatography (SFC) to
determine the amount of branched alkylphenol and linear alkylphenol
present. Quantification was performed using a calibration curve of
known mixtures of branched and linear alkylphenol.
[0193] % SA was determined on the dialysis residue fraction by
acidification of the product by a strong acid (hydrochloric acid)
in the presence of diethyl ether, followed by a potentiometric
titration on the organic fraction (tetra n-butyl ammonium hydroxide
was used as a titration agent). This method separates and
quantifies the alkyl salicylic acid and the remaining alkylphenol
(non-carboxylated alkylphenate). Results were expressed in
equivalent mg KOH per gram of product (Base Number unit). % SA was
then determined by using the following equation: %
SA=100*(Alkylsalicylic acid(Alkylphenol+Alkylsalicylic acid)) % Ca
in the residue was determined by classical X Ray spectrometry.
[0194] Dialysis results are as follows: TABLE-US-00009 Dialysate
51.1 wt % of starting sample weight Residue 48.9 wt % of starting
sample weight
[0195] Dialysate Composition: TABLE-US-00010 Dodecylphenol 1.0 wt %
Linear Alkylphenol 26.7 wt % 100N Base Oil 72.3 wt %
[0196] Residue Composition TABLE-US-00011 Calcium 9.3 wt % TBN 259
mg KOH/gm SAI 78 mg KOH/gm % SA 50
[0197] The following composition of the product produced in Example
3 was calculated from the composition of the dialysate and residue
fractions: TABLE-US-00012 Total Alkylphenol Content 14.1 wt % Oil
36.9 wt % Single Aromatic Ring Alkylsalicylate 24.5 wt % Calcium
Alkylphenate 24.5 wt %
Procedures for Performance Tests
[0198] The following Section described Performance Test Methods
referred to in these examples.
[0199] Bulk Oxidation (MIP-48)
[0200] The Modified IP-48 test (or MIP-48 test) is a bulk oil
oxidation test. The IP-48 test is test method 48 of the institute
of Petroleum and can be found in "Standard methods for analysis and
testing of petroleum and related products and British Standard 2000
parts, 2000, Methods IP-1-324, Volume 1" published on behalf of the
institute of petroleum (London) by John Wiley & Sons, LTD
(Chisester, New York, Weinheim, Brisbane, Singapore, Toronto). In
said test, air is bubbled through a lubricant sample which is kept
at high temperature. The viscosity of the end-of-test sample is
compared to that of a reference sample which hs the exact same
composition but is bubbled through with nitrogen. The net viscosity
increase (expressed as a percentage increase) is an indication for
the oxidation stability of a lubricant. The lower the viscosity
increase, the better.
[0201] Corrosion Control (ASTM D6594-01)
[0202] This is a standard test method for evaluation of
corrosiveness of diesel engine oil at 135.degree. C. This test
method is used to test diesel engine lubricants to determine their
tendency to corrode various metals, specifically alloys of lead and
copper commonly used in cam followers and bearings. Four metal
specimens of copper, lead, tin, and phosphor bronze are immersed in
a measured amount of engine oil. The oil, at an elevated
temperature, is blown with air for a period of time. When the test
is completed, the copper specimen and the stressed oil are examined
to detect corrosion and corrosion products, respectively.
Examples Showing Performance Advantages
[0203] The following Examples illustrate performance advantages
demonstrated by lubricating oil compositions containing the
unsulfurized carboxylate-containing additive of the present
invention.
Example 4
[0204] Marine Engine Oils Performance
[0205] The lubrication oil formulations used in the present example
were generated for lubricants intended for use in Marine Trunk
Piston Engines and had the following compositions: TABLE-US-00013
Formula 1 Phenate-Stearate 6.04% Zinc Dithiophosphate 0.64% Foam
Inhibitor 0.04% Commercial detergent-dispersant 14.72%
[0206] TABLE-US-00014 Formula 1A Phenate-Stearate 6.04% Zinc
Dithiophosphate 0.64% Foam Inhibitor 0.04% Unsulfurized,
carboxylate-containing additive 10.17% prepared according to
Example 1
[0207] TABLE-US-00015 Formula 2 Phenate 7.22% Zinc Dithiophosphate
0.64% Foam Inhibitor 0.04% Commercial detergent-dispersant
16.83%
[0208] TABLE-US-00016 Formula 2A Phenate 7.22% Zinc Dithiophosphate
0.64% Foam Inhibitor 0.04% Unsulfurized, carboxylate-containing
additive 11.05% prepared according to Example 1
[0209] TABLE-US-00017 Formula 3 HOB Salicylate 8.93% Zinc
Dithiophosphate 0.64% Foam Inhibitor 0.04% MOB Salicylate 8.88%
[0210] TABLE-US-00018 Formula 3A HOB Salicylate 8.93% Zinc
Dithiophosphate 0.64% Foam Inhibitor 0.04% Unsulfurized,
carboxylate-containing additive 8.72% prepared according to Example
1
[0211] TABLE-US-00019 Formula 4A Carboxy-Stearate 8.83% Zinc
Dithiophosphate 0.64% Foam Inhibitor 0.04% Unsulfurized,
carboxylate-containing additive 8.72% prepared according to Example
1
[0212] The treat rates of these concentrated additives in finished
oil were adjusted to ensure a BN of 40 mg KOH/g according to ASTM
D2896 for the finished lubricant. TABLE-US-00020 Results of Bulk
Oxidation Test For- mula Formula Formula Formula Formula Formula
Formula 1 1A 2 2A 3 3A 4A MIP-48 39 17 45 25 24 22 20 results
[0213] The results of the MIP-48 bulk oxidation test show that the
unsulfurized, carboxylate-containing additive of the present
invention has surprisingly better viscosity increase control (VIC)
compared to a commercial detergent-dispersant when tested at the
same BN level in the same formulation.
Example 5
Automotive Performance
[0214] The lubrication oil formulations used in the present example
were designed for Low Emission Diesel Lubricants (LEDL) intended
for use in Low Emission Diesel Engines and had the following
compositions: TABLE-US-00021 Baseline Formulation A A B B C C
Sulfated Ash, % 0.95 0.95 1.0 1.0 1.0 1.0 Sulphur, % 0.10 0.10 0.12
0.12 0.10 0.10 Phosphorus, % 0.05 0.05 0.05 0.05 0.05 0.05 Borated
Dispersant Y Y Y Y Y Y Non-Borated Dispersant Y Y Y Y Y Y LOB
Ca-Sulfonate N N Y Y N N LOB Salicylate N N N N Y Y Commercially
Available Salicylate, wt % 4.5 N 4.5 N 4.5 N Unsulfurized,
carboxylate-containing additive N 5.0 N 5.0 N 5.0 prepared
according to Example 1 Secondary ZnDTP Y Y Y Y Y Y Diphenylamine
Anti-Oxidant Y Y Y Y Y Y Molybdenum Anti-Oxidant Y Y Y Y Y Y Foam
Inhibitor Y Y Y Y Y Y OCP VII Y Y Y Y Y Y Base Oil 1 Y Y Y Y Y Y
Base Oil 2 Y Y Y Y Y Y HTCBT 118 60 140 74 230 108 Pb, ppm
[0215] For each formulation, the unsulfurized,
carboxylate-containing additive of the present invention was
compared to a commercially available salicylate for corrosion
performance. In each case, covering a range of sulfur, phosphorus
and ash levels, the carboxylate-containing additive of the present
invention displayed superior corrosion control performance.
[0216] While the present invention has been described with
reference to specific embodiments, this application is intended to
cover those various changes and substitutions that may be made by
those skilled in the art without departing from the spirit and
scope of the appended claims.
* * * * *