U.S. patent application number 15/059695 was filed with the patent office on 2016-09-08 for lubricating composition.
The applicant listed for this patent is SHELL OIL COMPANY. Invention is credited to Adam David MAYERNICK.
Application Number | 20160257904 15/059695 |
Document ID | / |
Family ID | 56849551 |
Filed Date | 2016-09-08 |
United States Patent
Application |
20160257904 |
Kind Code |
A1 |
MAYERNICK; Adam David |
September 8, 2016 |
LUBRICATING COMPOSITION
Abstract
The present invention provides the use of a lubricating
composition for improving anti-foaming properties, in particular as
determined according to ASTM D892, wherein the lubricating
composition comprises (i) a base oil comprising Fischer-Tropsch
derived base oil and (ii) from 0.0001 to 10 wt % of an anti-foam
agent.
Inventors: |
MAYERNICK; Adam David;
(Houston, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SHELL OIL COMPANY |
Houston |
TX |
US |
|
|
Family ID: |
56849551 |
Appl. No.: |
15/059695 |
Filed: |
March 3, 2016 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
62128711 |
Mar 5, 2015 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C10N 2020/02 20130101;
C10M 169/041 20130101; C10M 2229/02 20130101; C10M 2229/042
20130101; C10M 2229/051 20130101; C10M 169/04 20130101; C10N
2020/055 20200501; C10M 2201/105 20130101; C10M 2229/041 20130101;
C10M 2205/173 20130101; C10M 2209/084 20130101; C10M 2229/046
20130101; C10M 2229/04 20130101; C10N 2030/18 20130101 |
International
Class: |
C10M 169/04 20060101
C10M169/04; C10M 155/02 20060101 C10M155/02; C10M 145/14 20060101
C10M145/14; C10M 101/00 20060101 C10M101/00 |
Claims
1. Use of a lubricating composition for improving anti-foaming
properties, in particular as determined according to ASTM D892,
wherein the lubricating composition comprises (i) a base oil
comprising a Fischer-Tropsch derived base oil and (ii) from 0.0001
to 10 wt % of an anti-foam agent.
2. Use according to claim 1 wherein the anti-foam agent is selected
from silicone anti-foam agents, non-silicone anti-foam agents and
mixtures thereof.
3. Use according to claim 2 wherein the silicone anti-foam agents
are selected from silicone oils.
4. Use according to claim 3 wherein the silicone oils are selected
from polyalkylsiloxanes (e.g., polydimethylsiloxane),
polyarylsiloxanes, polyalkoxysiloxanes, polyaryloxysiloxanes,
fluorinated polysiloxanes (e.g., trifluoropropylmethylsilicone),
and mixtures thereof.
5. Use according to claim 1, wherein the anti-foam agent comprises
silica particulates.
6. Use according to claim 2 wherein the non-silicone anti-foam
agents are selected from polymethacrylates.
7. Use according to claim 1 wherein the Fischer-Tropsch derived
base oil has a kinematic viscosity at 100.degree. C. of from 1
mm.sup.2/s to 35 mm.sup.2/s.
8. Use according to claim 1 wherein the base oil comprises more
than 50 wt %, preferably more than 60 wt %, more preferably more
than 70 wt %, even more preferably more than 80 wt %, most
preferably more than 90 wt % of Fischer-Tropsch derived base
oil.
9. Method for improving anti-foaming properties of a lubricating
composition, in particular as determined according to ASTM D892,
wherein the method comprises providing a lubricating composition
which comprises (i) a base oil comprising a Fischer-Tropsch derived
base oil and (ii) 0.0001 to 10 wt % of an anti-foam agent.
10. A lubricating oil composition comprising (i) a base oil
comprising a Fischer-Tropsch derived base oil; and (ii) from 0.0001
to 10 wt % of an anti-foam agent.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a lubricating composition,
in particular to the use of said lubricating composition for
providing improved anti-foaming properties such as reduced form
formation and reduced stability of foam.
BACKGROUND OF THE INVENTION
[0002] Lubricating oils, including hydraulic oils, crankcase oils,
driveline lubricants, greases, marine lubricants, other types of
industrial lubricants, and the like, are often used to reduce
friction between members and to assist in the operation of many
mechanical constituents. Commonly, such lubricating oils are used
in environments in which the oil is subject to mechanical agitation
in the presence of air. As a consequence, air may undesirably
become entrained in the oil and/or cause the formation of foam.
[0003] Foam generally refers to a collection of air bubbles formed
in or on the surface of a liquid, while air entrainment generally
refers to the dispersion of air bubbles within a liquid. Air
entrainment and foaming in lubricating oils can be a serious
concern as it may lead to problems such as inadequate lubrication,
fluctuation of hydraulic pressure, poor hydraulic system
performance, incomplete oil films, component wear due to reduced
lubricant viscosity, and fluid deterioration due to accelerated
oxidation, which may eventually lead to mechanical failure or the
like. Lubricating oils therefore usually contain a defoaming
agent.
[0004] In general, as a defoaming agent for lubricating oil, it is
known to employ a silicone-based defoaming agent, such as
polydimethylsiloxane (PDMS), fluorosilicones and silicone glycols.
For instance, U.S. Pat. No. 6,251,840 discloses lubricating fluids
comprising a silicone-based antifoam agent. Similarly,
US20140018267 discloses a lubricating fluid comprising a
combination of three polydimethylsiloxane antifoam agents. It is
also known to use non-silicone anti-foam agents, such as
polymethacrylate anti-foams.
[0005] While it is known to use such anti-foaming agents in
lubricant compositions, it would be desirable to formulate
lubricating compositions having reduced foaming tendency.
[0006] As is disclosed in for example D. J. Wedlock et al.,
"Gas-to-Liquids Base Oils to assist in meeting OEM requirements
2010 and beyond", presented at the 2nd Asia-Pacific base oil
Conference, Beijing, China, 23-25 October 2007, the use of
Fischer-Tropsch derived base oils in lubricating compositions such
as engine oils, transmission fluids, and industrial lubricants can
result in various performance benefits. Examples of performance
benefits by the use of Fischer-Tropsch derived base oils mentioned
in the above article include: improved oxidation stability
properties, improved engine cleanliness, improved wear protection,
improved emissions and improved after-treatment device
compatibility. Also the Fischer-Tropsch base oils allow for the
formulation of low-viscosity energy conserving formulations and
exhibit very good cold flow properties and high viscosity indices
and low volatility.
[0007] It has been found by the present inventors that a
combination of anti-foam agents and Fischer-Tropsch derived base
oils can provide lubricating compositions having improved anti-foam
properties.
SUMMARY OF THE INVENTION
[0008] According to the present invention there is provided the use
of a lubricating composition for improving anti-foaming properties,
in particular as determined according to ASTM D892, wherein the
lubricating composition comprises (i) a base oil comprising a
Fischer-Tropsch derived base oil and (ii) from 0.0001 to 10 wt % of
an anti-foam agent.
[0009] It has surprisingly been found that the lubricating
compositions herein exhibit improved anti-foaming properties.
DETAILED DESCRIPTION OF THE INVENTION
[0010] An essential feature of the lubricating compositions herein
is at least one anti-foam agent.
[0011] The anti-foam agent is typically present in an amount of
from 0.0001 (1 ppm) to 10 wt %, preferably from 0.0001 to 8 wt %,
more preferably from 0.001 (10 ppm) to 1 wt %, even more preferably
from 0.001 (10 ppm) to 0.05 wt % (500 ppm), and especially from
0.005 to 0.02 wt %, by weight of the lubricant composition.
[0012] The anti-foam agent for use herein can be a silicone
anti-foam agent or a non-silicone anti-foam agent.
[0013] Suitable silicone anti-foam agents include silicone oils and
silicone resins, and the like.
[0014] In one embodiment of the present invention the anti-foam
agent comprises a silicone oil. The silicone oil is not generally
limited and may include any silicone oil known in the art that does
not adversely affect the lubricating properties of the resulting
lubricating oil composition. Suitable silicone oils may include any
liquid polymerized siloxane comprising one or more organic groups
("polyorganosiloxanes"). Examples of suitable silicone oils
include, but are not limited to, polyalkylsiloxanes (e.g.,
polydimethylsiloxane), polyarylsiloxanes, polyalkoxysiloxanes,
polyaryloxysiloxanes, fluorinated polysiloxanes (e.g.,
trifluoropropylmethylsilicone), combinations thereof, etc.
[0015] Polydimethylsiloxane is a known antifoam compound and may be
produced, for example, by the hydrolysis of dimethyldihalosilane
followed by condensation, or by the decomposition of
dimethylcyclosiloxane followed by condensation. In certain
embodiments, polydimethylsiloxane may be end blocked by the
trimethylsilyl group or hydroxyl group, but is not so limited.
[0016] Generally, silicone oils suitable for use in the present
invention have a kinematic viscosity at 25.degree. C. of at least
0.5 mm/s (cSt), or in a range of from 0.5 to 1,000,000 mm.sup.2/s
(cSt), or in a range of from 10,000 to 600,000 mm.sup.2/s (cSt).
Silicone oil may be present in an anti-foam agent in an amount in
the range of from 0.01 to more than 99 wt %, or in an amount in the
range of from 1 to 10 wt %, based on the total weight of the
anti-foam agent. Further, the concentration of silicone oil present
in the lubricating oil composition is typically in a range of from
0.1 to 500 ppm, from 1 to 100 ppm, or from 1 to 50 ppm.
[0017] In addition to, or instead of, the silicone oil, the
anti-foam agent may comprise silica particulates. Silica
particulates are not generally limited and may include any type of
silica particulates that are conventionally employed in anti-foam
agents, provided that the silica particulates do not adversely
affect the lubricating properties of the resulting lubricating oil
composition. Examples of suitable silica particulates may include,
but are not limited to, colloidal silica, fumed silica,
precipitated silica, silica aerogel, silica xerogel, silicas having
surface organosilyl groups, chemically treated silica, hydrophobic
silica, etc.
[0018] Suitable silica particulates may be produced by any known
method, for example, a dry method such as the thermal decomposition
of a silicon halide or the reaction of a substance containing
silicic acid under heat, or a wet method such as the decomposition
of a metal salt of silicic acid, e.g., sodium silicate, by an acid
or the aerogel method. Various grades of silica particulates are
commercially available from a variety of sources in a variety of
particle size distributions. Although the size of silica
particulates suitable for use in the anti-foam agent is not
particularly limited, the silica particulates generally may have a
particle size of from about 1 nanometers (nm) to several microns.
Preferably, the silica particulates may have a particle size of
from about 1 to 1000 nm.
[0019] A silica aerogel is one kind of silica that may be employed.
Briefly, such materials are prepared by displacing water from a
silica hydrogel with a low boiling organic liquid such as ethyl
alcohol, heating the treated gel in an autoclave to approximately
the critical temperature of the organic liquid, and then releasing
the vapors of the organic liquid from the autoclave whereby
excessive shrinking or crushing of the cellular structure of the
silica is avoided. The details of this technique are described in
the literature and silica aerogels are commercially available.
[0020] Preferred silica particulates include "Aerosil.RTM. R208"
and "Aerosil.RTM. R812" available from Evonik Industries, fumed
silica available from Sigma-Aldrich Co. LLC and silica available
from Chemicell GmbH.
[0021] Silica particulates may be present in the anti-foam agent in
an amount in the range of from 0.01 to more than 99 wt %, or in an
amount in the range of from 0.1 to 10 wt %, based on the total
weight of the anti-foam agent. Further, when present, the
concentration of silica particulates present in the lubricating oil
composition is typically in a range of from 0.1 to 500 ppm, from 1
to 100 ppm, or from 1 to 50 ppm.
[0022] Non-silicone types of anti-foams may also be used as the
anti-foam agent herein. Suitable non-silicone anti-foam agents
include, for example, a polyalkyl acrylate, an alcohol
ethoxy/propoxylate, a fatty acid ethoxy/propoxylate, a sorbitan
partial fatty acid ester, and the like. Suitable non-silicone
anti-foam agents include polymethacrylates, such as that
commercially available from Cytec Industries under the trade name
PC1644.
[0023] Optionally, anti-foam agents may further comprise a solvent,
such as a paraffinic mineral oil, naphthenic mineral oil, petroleum
naphtha, aromatics, toluene, xylene, benzene, hexane, heptane,
octane, dodecane, kerosene, etc. and combinations thereof.
Optionally, the silicone oil may be dispersed or dissolved in the
solvent.
[0024] In certain embodiments, the lubricating oil composition can
include a solvent in which the anti-foam compound(s) can be
dissolved.
[0025] Examples of commercially available anti-foam agents suitable
for use in the lubricating compositions herein include PC 1644
(polymethacrylate type) commercially available from Cytec
Industries, Synative AC AMH-2 (a non-silicone anti-foam agent)
commercially available from BASF, Xiameter PMX-200 (a
silicone-based anti-foam agent) commercially available from Dow
Corning and Foam Ban 149 (a silicone-based anti-foam agent)
commercially available from Munzing.
[0026] The base oil used in the lubricating composition herein
comprises a Fischer-Tropsch derived base oil.
[0027] Fischer-Tropsch derived base oils are known in the art. By
the term "Fischer-Tropsch derived" is meant that a base oil is, or
is derived from, a synthesis product of a Fischer-Tropsch process.
A Fischer-Tropsch derived base oil may also be referred to as a GTL
(Gas-To-Liquids) base oil. Suitable Fischer-Tropsch derived base
oils that may be conveniently used as the base oil in the
lubricating composition of the present invention include those, for
example, disclosed in EP0776959, EP0668342, WO1997021788,
WO2000015736, WO2000014188, WO2000014187, WO2000014183,
WO2000014179, WO2000008115, WO1999041332, EP1029029, WO2001018156
and WO2001057166.
[0028] Typically, the aromatics content of a Fischer-Tropsch
derived base oil, (as measured by IP-368, ASTM D2007, ASTM D7419),
will be less than about 1 wt. %, alternatively less than about 0.5
wt. % or in alternate embodiments, less than about 0.1 wt. %. The
base oil can have a total paraffin content of at least about 80 wt.
%, alternatively at least about 85 wt. %, alternatively at least
about 90 wt. %, alternatively at least about 95 wt. %, or, in
certain embodiments, at least about 99 wt. %. The Fischer-Tropsch
derived base oil can have a saturates content (as measured by
IP-368, ASTM D2007, ASTM D7419, or any other chromatographic method
that will yield similar results) of greater than about 98 wt. %,
alternatively greater than about 99 wt. %, or alternatively greater
than about 99.5 wt. %. The Fischer-Tropsch derived base oil can
further include a maximum n-paraffin content of about 0.5 wt. % and
naphthenic compound content of from 0 to less than 20 wt. %,
alternatively from about 0.5 to 10 wt. %, alternatively from about
1-5 wt. %, or alternatively from about 5-10 wt. %.
[0029] Typically, the Fischer-Tropsch derived base oil or base oil
blend has a kinematic viscosity at 100.degree. C. (as measured by
ASTM D 7042) in the range of from 1 to 35 mm.sup.2/s (cSt),
alternatively from 1 to 25 mm.sup.2/s (cSt), alternatively from 2
to 20 mm.sup.2/s (cSt), or alternativley from 2 mm.sup.2/s to 12
mm.sup.2/s. The Fischer-Tropsch derived base oil can have a
kinematic viscosity at 100.degree. C. (as measured by ASTM D 7042)
of at least 2.5 mm.sup.2/s, alternatively at least 3.0 mm.sup.2/s
(e.g., "GTL 3"). In certain embodiments of the present invention,
the Fischer-Tropsch derived base oil can have a kinematic viscosity
at 100.degree. C. of not greater than 5.0 mm.sup.2/s, alternatively
not greater than 4.5 mm.sup.2/s, alternatively not greater than 4.2
mm.sup.2/s (e.g., "GTL 4"). In certain embodiments of the present
invention, the Fischer-Tropsch derived base oil has a kinematic
viscosity at 100.degree. C. of not greater than 8.5 mm.sup.2/s,
alternatively not greater than 8 mm.sup.2/s (e.g., "GTL 8"). Other
grades of GTL products would also be possible, based upon the
specific distillation process utilized to produce the GTL
product.
[0030] Further, the Fischer-Tropsch derived base oil can have a
kinematic viscosity at 40.degree. C. (as measured by ASTM D445) of
from 10 to 100 mm.sup.2/s (cSt), alternatively from 15 to 50
mm.sup.2/s, alternatively from 50 to 80 mm.sup.2/s, alternatively
greater than 100 mm.sup.2/s.
[0031] Also, in certain embodiments, the Fischer-Tropsch derived
base oil can have a pour point (as measured according to ASTM D
5950) of less than about -10.degree. C., alternatively less than
about -20.degree. C., alternatively less than about -30.degree. C.,
alternatively less than about -40.degree. C., and alternatively
less than about -45.degree. C.
[0032] The flash point (as measured by ASTM D92) of the
Fischer-Tropsch derived base oil can be greater than 120.degree.
C., alternatively greater than 130.degree. C., alternatively
greater than 140.degree. C.
[0033] The Fischer-Tropsch derived base oil can have a viscosity
index (according to ASTM D 2270) in the range of from about 100 to
200. Alternatively, the Fischer-Tropsch derived base oil can have a
viscosity index of at least 125, alternatively at least 130. In
certain embodiments, the viscosity index is less than 180,
alternatively less than 160, alternatively less than 150. In
certain embodiments, the viscosity index can be between 125 and
180, alternatively between 130 and 160.
[0034] In the event the Fischer-Tropsch derived base oil contains a
blend of two or more Fischer-Tropsch derived base oils, the above
values apply to the blend of the two or more Fischer-Tropsch
derived base oils.
[0035] As used herein, the term "base oil" may refer to a mixture
containing more than one base oil. Suitable base oils for use in
the lubricating oil composition herein in addition to the
Fischer-Tropsch derived base oil include one or more of the mineral
derived or synthetic base oils selected from Group I, II, III or V
base oils or Group IV poly-alpha olefins (PAOs), and mixtures
thereof.
[0036] By "Group I", "Group II", "Group III", "Group IV" and "Group
V" base oils as used herein are meant lubricating oil base oils
according to the definitions of American Petroleum Institute (API)
for category I, II, III, IV and V. These API categories are defined
in API Publication 1509, 15th Edition, Appendix E, July 2009.
[0037] Poly-alpha olefin base oils (PAOs) and their manufacture are
well known in the art. Suitable poly-alpha olefin base oils for use
in the lubricating compositions herein may be derived from linear
C.sub.2 to C.sub.32, preferably C.sub.6 to C.sub.16, alpha olefins.
Examples of suitable feedstocks for said poly-alpha olefins can be
1-octene, 1-decene, 1-dodecene and 1-tetradecene.
[0038] In certain embodiments, the base oil as used in the
lubricating composition can include a first GTL base oil, and may
optionally include one or more of the oils selected from PAO, or
Group I, II, III or V base oils.
[0039] Preferably, the base oil contains more than 50 wt. %,
preferably more than 60 wt. %, more preferably more than 70 wt. %,
even more preferably more than 80 wt. %, and most preferably more
than 90 wt. % of a Fischer-Tropsch derived base oil. In an
alternate embodiment, not more than 5 wt. %, alternatively not more
than 2 wt. %, of the base oil is not a Fischer-Tropsch derived base
oil. In certain preferred embodiments, 100 wt % of the base oil is
based on one or more Fischer-Tropsch derived base oils.
[0040] Preferably the base oil or base oil blend that includes the
Fischer-Tropsch derived base oil has a kinematic viscosity at
100.degree. C. of between 2 and 35 cSt, alternatively between 2 and
10.5 cSt (according to ASTM D 445).
[0041] In certain embodiments, the total amount of base oil that is
incorporated in the lubricating composition herein is preferably an
amount in the range of from 60 to 99 wt. %, alternatively an amount
in the range of from 65 to 90 wt. %, and in certain preferred
embodiments, in an amount in the range of from 70 to 85 wt. %, with
respect to the total weight of the lubricating composition.
[0042] Optionally, the lubricating oil compositions herein can also
include a solvency booster. As used herein, the term "solvency
booster" means a component which enhances the solvency of the
Fischer-Tropsch derived base oil with respect to certain additives
that are included in the formulation. In certain embodiments, the
solvency booster is present in an amount of between about 1 and 30
wt %, alternatively in an amount of between about 2 and 20 wt %, or
alternatively in an amount between about 5 and 15 wt %. Compounds
suitable for use as a solvency booster can be selected from
alkylated aromatic compounds, naphthenic base oils, ester base
oils, and mixtures thereof.
[0043] Alkylated naphthalenes may be produced by any suitable means
known in the art, from naphthalene itself or from substituted
naphthalenes which may contain one or more short chain alkyl groups
having up to about eight carbon atoms, for example methyl, ethyl,
and propyl. Suitable alkyl-substituted naphthalenes include
alphamethylnaphthalene, dimethylnaphthalene, and ethylnaphthalene.
Naphthalene itself is especially suitable since the resulting
mono-alkylated products have better thermal and oxidative stability
than the more highly alkylated materials. Suitable alkylated
naphthalene lubricant compositions are described in U.S. Pat. No.
3,812,036, and U.S. Pat. No. 5,602,086. The preparation of
alkylnaphthalenes is further disclosed in U.S. Pat. No.
4,714.794.
[0044] The alkylated aromatic compound for use herein can be
selected from alkylbenzene compounds, alkylnaphthalene compounds,
and mixtures thereof.
[0045] The alkylaromatic component preferably has a kinematic
viscosity at 100.degree. C. in the range of from 3 to 12
mm.sup.2/s, more preferably in the range of from 3.8 to 7
mm.sup.2/s. The viscosity index of the alkylaromatic component is
above 40, preferably at or above 70.
[0046] An exemplary alkylated aromatic compound for use herein is
an alkylnaphthalene compound. Examples of commercially available
alkylnaphthalene compounds are those under the tradename NA-Lube
(King Industries), such as NA-Lube KR 008, NA-Lube KR019, and the
like, and those under the tradename Mobil MCP (ExxonMobil).
[0047] Examples of commercially available alkyl benzenes include
those available under the tradename Fusyn-22 (Formosan), those
available under the tradename Janex HAL (Janex), and those
available under the tradename ZEROL (Shreive Chemical Products,
Inc. (SCP)).
[0048] Suitable naphthenic base oils for use as a solvency booster
herein includes naphthenic base oils having low viscosity index
(VI), typically between about 40-80, and a low pour point, for
example, a temperature of less than -20.degree. C. Such base oils
can be produced from feedstocks rich in naphthenes and low in wax
content. There is no particular limitation on the type of
mineral-derived naphthenic base oil which can be used in the base
oil composition herein. Any mineral-derived naphthenic base oil
which is suitable for use in a lubricating oil composition can be
used herein. Naphthenic base oils are defined as Group V base oils
according to API. Such mineral-derived base oils can be obtained by
refinery processes starting from naphthenic crude feeds.
Mineral-derived naphthenic base oils for use herein preferably have
a pour point of below -20.degree. C. and a viscosity index of less
than 70. Such base oils can be produced from feedstocks rich in
naphthenes and low in wax content. Mineral-derived naphthenic base
oils are well known and described in more detail in "Lubricant base
oil and wax processing", Avilino Sequeira, Jr., Marcel Dekker, Inc,
New York, 1994, ISBN 0-8247-9256-4, pages 28-35. Methods of
manufacture of naphthenic base oils can be found in "Lubricants and
Lubrication (Second, Completely Revised and Extended Edition)",
published by Wiley-VCH Verlag GmbH & Co. KgaA, Chapter 4, pages
46-48.
[0049] An example of a suitable naphthenic base oil for use as a
solvency booster herein is that commercially available under the
tradename KN4006 (China National Petroleum Corporation). Other
examples of suitable naphthenic base oils for use as a solvency
booster herein include those available under the tradenames
Hydrocal, Hydrosol and HR Tufflo (Calumet Specialty Products), and
those commercially available under the tradename Nynas (Nynas Oil
Company).
[0050] Suitable esters for use as a solvency booster herein include
natural and synthetic esters such as diesters and polyol esters. An
example of a suitable ester for use as a solvency booster herein is
the saturated polyol ester commercially available under the
tradename Priolube 3970 (Croda International PLC). Other suitable
esters for use as a solvency booster herein include those available
under the tradename Radialube (Oleon), those available under the
tradename Emery (from Emery) and those available under the
tradename Esterex (ExxonMobil Chemical).
[0051] The lubricating oil compositions herein can include one or
more detergent compounds having a TBN (total base number
equivalent, as determined by ASTM D2896) of between about 0 and
400. In certain embodiments, the detergent compound can include one
or more alkaline earth metal salicylate. Suitable alkaline earth
metal salicylates include calcium, magnesium and barium
salicylates, and mixtures thereof, preferably calcium
salicylates.
[0052] The lubricating oil compositions herein preferably comprise
from 0.01 wt % to 9 wt %, more preferably from 1 wt % to 6 wt %,
even more preferably from 3.5 wt % to 5.5 wt %, of detergent, by
weight of the lubricating oil composition.
[0053] In certain embodiments, the lubricating oil compositions
herein can include one or more anti-oxidants. Suitable
anti-oxidants for use herein include phenolic antioxidants and/or
aminic antioxidants.
[0054] In one embodiment, said antioxidants are present in an
amount in the range of from 0.1 to 5.0 wt. %, preferably in an
amount in the range of from 0.3 to 3.0 wt. %, and more preferably
in an amount of in the range of from 0.5 to 1.5 wt. %, based on the
total weight of the lubricating oil composition.
[0055] Examples of aminic antioxidants which may be conveniently
used include alkylated diphenylamines,
phenyl-.alpha.-naphthylamines, phenyl-.beta.-naphthylamines and
alkylated .alpha.-naphthylamines.
[0056] Exemplary aminic antioxidants include dialkyldiphenylamines,
such as p,p'-dioctyl-diphenylamine,
p,p'-di-.alpha.-methylbenzyl-diphenylamine, and
N-p-butylphenyl-N-p'-octylphenylamine, monoalkyldiphenylamines,
such as mono-t-butyldiphenylamine and mono-octyldiphenylamine,
bis(dialkylphenyl)amines, such as di-(2,4-diethylphenyl)amine and
di(2-ethyl-4-nonylphenyl)amine, alkylphenyl-1-naphthylamines, such
as octylphenyl-1-naphthylamine and
n-t-dodecylphenyl-1-naphthylamine, 1-naphthylamine,
arylnaphthylamines, such as phenyl-1-naphthylamine,
phenyl-2-naphthylamine, N-hexylphenyl-2-naphthylamine and
N-octylphenyl-2-naphthylamine, phenylenediamines, such as
N,N'-diisopropyl-p-phenylenediamine and
N,N'-diphenyl-p-phenylenediamine, and phenothiazines, such as
phenothiazine and 3,7-dioctylphenothiazine.
[0057] Preferred aminic antioxidants include those available under
the following trade designations: "Sonoflex OD-3" (Seiko Kagaku
Co.), "Irganox L-57" (Ciba Specialty Chemicals Co.) and
phenothiazine (Hodogaya Kagaku Co.).
[0058] Exemplary phenolic antioxidants that may be used include
C.sub.7-C.sub.9 branched alkyl esters of
3,5-bis(1,1-dimethyl-ethyl)-4-hydroxy-benzenepropanoic acid,
2-t-butylphenol, 2-t-butyl-4-methylphenol,
2-t-butyl-5-methylphenol, 2,4-di-t-butylphenol,
2,4-dimethyl-6-t-butylphenol, 2-t-butyl-4-methoxyphenol,
3-t-butyl-4-methoxyphenol, 2,5-di-t-butylhydroquinone,
2,6-di-t-butyl-4-alkylphenols such as 2,6-di-t-butylphenol,
2,6-di-t-butyl-4-methylphenol and 2,6-di-t-butyl-4-ethylphenol,
2,6-di-t-butyl-4-alkoxyphenols such as
2,6-di-t-butyl-4-methoxyphenol and 2,6-di-t-butyl-4-ethoxyphenol,
3,5-di-t-butyl-4-hydroxybenzylmercaptooctylacetate,
alkyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionates such as
n-octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate,
n-butyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate and
2'-ethylhexyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate,
2,6-d-t-butyl-.alpha.-dimethylamino-p-cresol,
2,2'-methylene-bis(4-alkyl-6-t-butylphenol) such as
2,2'-methylenebis(4-methyl-6-t-butylphenol, and
2,2-methylenebis(4-ethyl-6-t-butylphenol), bisphenols such as
4,4'-butylidenebis(3-methyl-6-t-butylphenol,
4,4'-methylenebis(2,6-di-t-butylphenol),
4,4'-bis(2,6-di-t-butylphenol), 2,2-(di-p-hydroxyphenyl)propane,
2,2-bis(3,5-di-t-butyl-4-hydroxyphenyl)propane,
4,4'-cyclohexylidenebis(2,6-t-butylphenol),
hexamethyleneglycol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate],
triethyleneglycolbis[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate],
2,2'-thio-[diethyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate],
3,9-bis{1,1-dimethyl-2-[3-(3-t-butyl-4-hydroxy-5-methyl-phenyl)propionylo-
xy]ethyl}2,4,8,10-tetraoxaspiro[5,5]undecane,
4,4'-thiobis(3-methyl-6-t-butylphenol) and
2,2'-thiobis(4,6-di-t-butylresorcinol), polyphenols such as
tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane,
1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane,
1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene,
bis-[3,3'-bis(4'-hydroxy-3'-t-butylphenyl)butyric acid]glycol
ester,
2-(3',5'-di-t-butyl-4-hydroxyphenyl)methyl-4-(2'',4''-di-t-butyl-3''-hydr-
oxyphenyl)methyl-6-t-butylphenol and
2,6-bis(2'-hydroxy-3'-t-butyl-5'-methylbenzyl)-4-methylphenol, and
p-t-butylphenol--formaldehyde condensates and
p-t-butylphenol--acetaldehyde condensates.
[0059] Phenolic antioxidants include those available under the
following trade designations: "Irganox L-135" (Ciba Specialty
Chemicals Co.), "Yoshinox SS" (Yoshitomi Seiyaku Co.), "Antage
W-400" (Kawaguchi Kagaku Co.), "Antage W-500" (Kawaguchi Kagaku
Co.), "Antage W-300" (Kawaguchi Kagaku Co.), "Irganox L-109" (Ciba
Speciality Chemicals Co.), "Tominox 917" (Yoshitomi Seiyaku Co.),
"Irganox L-115" (Ciba Speciality Chemicals Co.), "Sumilizer GA80"
(Sumitomo Kagaku), "Antage RC" (Kawaguchi Kagaku Co.), "Irganox
L-101" (Ciba Speciality Chemicals Co.), "Yoshinox 930" (Yoshitomi
Seiyaku Co.).
[0060] The lubricating oil composition herein may include mixtures
of one or more phenolic antioxidants with one or more aminic
antioxidants.
[0061] According to the present invention, the lubricating
composition preferably includes up to about 30 wt % of a viscosity
modifier, based on the total weight of the lubricating composition.
In one embodiment, the lubricating composition comprises from 20 wt
% to 30 wt % of a viscosity modifier. In another embodiment, the
lubricating composition includes up to about 20 wt % of a viscosity
modifier. In an alternate embodiment, the lubricating composition
includes between about 10 and 20 wt % of a viscosity modifier. In
yet another embodiment, the lubricating composition includes
between about 1 and 10 wt % of a viscosity modifier. In a preferred
embodiment of the present invention, the lubricating composition is
essentially free of viscosity modifier. In a particularly preferred
embodiment of the present invention, the lubricating composition
comprises 0 wt % of a viscosity modifier.
[0062] Examples of viscosity index improvers include copolymers of
alpha-olefins and dicarboxylic acid esters such as those described
in U.S. Pat. No. 4,931,197. Commercially available copolymers of
alpha-olefins and dicarboxylic acid diesters include the Ketjenlube
polymer esters available from Italmatch (and previously Akzo Nobel
Chemicals). Other suitable examples of viscosity index improvers
are polyisobutylenes; commercially available polyisobutylenes
include the Oloa.RTM. products (Chevron Oronite).
[0063] Further examples of viscosity index improvers which may
conveniently be used in the lubricating compositions herein include
the styrene-butadiene stellate copolymers, styrene-isoprene
stellate copolymers and the polymethacrylate copolymers and
ethylene-propylene copolymers (also known as olefin copolymers) of
the crystalline and non-crystalline type.
[0064] Suitable olefin copolymers include those commercially
available under the trade designation "PARATONE.RTM." (such as
"PARATONE.RTM. 8921" and "PARATONE.RTM. 8941") (Chevron Oronite
Company LLC); those commercially available under the trade
designation "HiTEC.RTM." (such as "HiTEC.RTM. 5850B") (Afton
Chemical Corporation); and those commercially available under the
trade designation "Lubrizol.RTM. 7067C" (The Lubrizol Corporation).
Suitable polyisoprene polymers include those commercially available
under the trade designation "SV200" (Infineum International Ltd.).
Suitable diene-styrene copolymers include those commercially
available under the trade designation "SV 260" (Infineum
International Ltd).
[0065] The compositions herein may also include one or more
anti-wear additives. Suitable anti-wear additives for use herein
include zinc dithiophosphate compounds selected from zinc dialkyl-,
diaryl- and/or alkylaryl-dithiophosphates, molybdenum-containing
compounds, and ashless anti-wear additives such as substituted or
unsubstituted thiophosphoric acids, and salts thereof.
[0066] Examples of ashless thiophosphates are known in the art.
These compounds are metal-free organic compounds. Suitable ashless
thiophosphates for use in the lubricating oil composition herein
may include esters and/or salts of thiophosphoric acids, and
substituted thiophosphoric acids. Preferably, the ashless
thiophosphates are substituted by one or more hydrocarbyl groups
which hydrocarbyl groups can optionally contain an acid, a hydroxy
and/or an ester group. The hydrocarbyl moiety preferably is an
alkyl group containing up to 12 carbon atoms. The
hydrocarbyl-substituted thiophosphate preferably contains 2 or 3
hydrocarbyl groups, or is a mixture of thiophosphates containing 2
and 3 hydrocarbyl groups.
[0067] The ashless thiophosphates can contain any number of sulphur
atoms directly linked to the phosphorus atom. Preferably, the
thiophosphates are monothiophosphates and/or dithiophosphates.
[0068] Examples of ashless thiophosphates which may be conveniently
used in the lubricating oil composition herein are described in
EP0375324, U.S. Pat. No. 5,922,657, U.S. Pat. No. 4,333,841 and
U.S. Pat. No. 5,093,016, and may be conveniently made according to
the methods described therein.
[0069] Examples of commercially available ashless thiophosphates
that may be conveniently used in the lubricating oil composition
herein include those available under the trade designations
"IRGALUBE L-63" and "IRGALUBE 353" (Ciba Specialty Chemicals) and
that available under the trade designation "LZ 5125"
(Lubrizol).
[0070] In certain embodiments, the lubricating composition can
include one or more anti-wear additives selected from one or more
zinc dithiophosphates. The or each zinc dithiophosphate may be
selected from zinc dialkyl-, diaryl- or
alkylaryl-dithiophosphates.
[0071] Examples of zinc dithiophosphates which are commercially
available include those available under the trade designations "Lz
677A", "Lz 1095", "Lz 1097", "Lz 1370", "Lz 1371", "Lz 1373" and
"Lz 1395" (Lubrizol Corp.), those available under the trade
designations "OLOA 260", "OLOA 262", "OLOA 267" and "OLOA 269R"
(Chevron Oronite), and those available under the trade designation
"HITEC 7169" and "HITEC 7197" (Afton Chemical).
[0072] In certain embodiments, the lubricating composition herein
includes a phosphorus containing compound, preferably selected from
the group consisting of phosphonates, phosphates, phosphites,
phosphorothionates and dithiophosphates, and combinations thereof.
Examples of commercially available dithiophosphates and phosphates
are "IRGALUBE 63" and IRGALUBE 349", respectively, both available
from Ciba Specialty Chemicals.
[0073] The lubricating oil composition of the present invention has
a kinematic viscosity at 40.degree. C. in the range of from 2
mm.sup.2/s to 220 mm2/s, preferably in the range of from 32
mm.sup.2/s to 220 mm.sup.2/s.
[0074] In addition to the components mentioned above, the
lubricating composition herein may further include one or more
additional additives such as dispersants, extreme-pressure
additives, friction modifiers, viscosity index improvers, pour
point depressants, metal passivators, corrosion inhibitors,
demulsifiers, anti-corrosion agents, seal compatibility agents and
additive diluent base oils, etc.
[0075] As the person skilled in the art is familiar with the above
and other additives, these are not further discussed here in
detail.
[0076] Specific examples of such additives are described in for
example Kirk-Othmer Encyclopedia of Chemical Technology, third
edition, volume 14, pages 477-526.
[0077] The above-mentioned additives are typically present in an
amount in the range of from 0.01 to 35.0 wt. %, based on the total
weight of the lubricating composition, preferably in an amount in
the range of from 0.05 to 25.0 wt. %, more preferably from 0.1 to
20.0 wt. %, based on the total weight of the lubricating
composition.
[0078] The lubricating compositions herein may be conveniently
prepared by admixing the one or more additives with the base
oil(s).
[0079] The lubricant composition described herein can find a
variety of uses as a lubricant, including but not limited to,
passenger car engine oils, heavy duty diesel engine oils,
transmission lubricants, turbine oils, air compressor lubricants,
hydraulic fluids, gear oils, greases, transformer oils, marine
lubricants, and the like.
[0080] According to another aspect of the present invention there
is provided a method of improving anti-foaming properties of a
lubricating composition, in particular as determined according to
ASTM D892, wherein the method comprises providing a lubricating
composition which comprises a Fischer-Tropsch derived base oil and
from 0.0001 to 10 wt % of an anti-foam agent.
[0081] Also provided herein is a method for lubricating an internal
combustion engine, the method comprising the step of lubricating
said engine with the lubricating compositions described
hereinabove.
[0082] The present invention is described below with reference to
the following Examples, which are not intended to limit the scope
of the present invention in any way.
EXAMPLES
Lubricating Oil Compositions
[0083] Various combinations of additives and base oils were
formulated. Table 1 shows the properties of the base oils.
[0084] "Base oil 1" (or "BO1" or "GTL 4") was a Fischer-Tropsch
derived base oil having a kinematic viscosity at 100.degree. C.
(ASTM D445) of approximately 3.89 cSt (mm.sup.2s.sup.-1). Base oil
1 may be conveniently manufactured by the process described in e.g.
WO2002070631, the teaching of which is hereby incorporated by
reference.
[0085] "Base oil 2" (or "BO2") was a commercially available Group
III base oil having a kinematic viscosity at 100.degree. C. (ASTM
D445) of approximately 4.3 cSt. Base oil 2 is commercially
available from e.g. SK Energy (Ulsan, South Korea) under the trade
designation Yubase 4.
TABLE-US-00001 TABLE 1 Base Oil 1 Base Oil 2 (GTL 4) (Yubase 4)
Kinematic viscosity at 18.11 19.50 40.degree. C..sup.1 [cSt]
Kinematic viscosity at 4.083 4.260 100.degree. C..sup.1 [cSt] VI
Index.sup.2 128 126 Pour point.sup.3 [.degree. C.] -39 -15 Noack
volatility.sup.4 12.3 15.4 [wt. %] Saturates.sup.5 [wt. %] 99.8
99.8 Tertiary Carbon, %.sup.6 14.0 17.7 Secondary Carbon, %.sup.6
67.3 66.0 Primary Carbon, %.sup.6 17.5 15.1 Epsilon carbon content,
11.3 14.1 %.sup.6 n- and iso-paraffins.sup.7 n.d. n.d.
Mono-naphthenics.sup.7 n.d. n.d. di- and poly- n.d. n.d.
naphthenics.sup.7 Aromatics.sup.5 0.5 0.2 Dynamic viscosity at
-20.degree. C..sup.8 <900 <900 [cP] Dynamic viscosity at
-25.degree. C..sup.8 <900 <900 [cP] Dynamic viscosity at
-30.degree. C..sup.8 990 1460 [cP] Dynamic viscosity at -35.degree.
C..sup.8 1820 2740 [cP] .sup.1According to ASTM D 445
.sup.2According to ASTM D 2270 .sup.3According to ASTM D 5950
.sup.4According to CEC L-40-A-93/ASTM D 5800 .sup.5According to IP
368 (modified) .sup.6According to 13C NMR .sup.7According to FIMS
.sup.8According to ASTM D 5293 n.d. = not determined
Anti-Foam Test
[0086] In order to measure the anti-foaming performance of the
various lubricating compositions set out herein, the lubricating
compositions were subjected to the ASTM D892 test. In this test
method, air is flowed through 200 mL of a lubricating oil sample
for five minutes each at three oil temperatures of 24.degree. C.
(Seq I), 93.5.degree. C. (Seq II), and 24.degree. C. (Seq III) and
the volume of foam formed after flowing air as well as after 10
minutes of settling time are measured. Results from ASTM D892 are
reported as (mL foam after 5 minute blowing period)/(mL foam after
10 minute setting period). Improved anti-foam benefits are
evidenced by a lower volume of foam (in mL).
Examples 1-8 and Comparative Examples 1-8
[0087] Table 2 below shows the formulations of Examples 1-8 and
Comparative Examples 1-8 and the results when these formulations
were subjected to the anti-foam test ATSM D892. In Table 2, PC
1644, Synative AC AMH-2, Xiameter PMX-200 and Foam Ban 149 are all
anti-foam agents. PC 1644 is commercially available from Cytec
Industries. Synative AC AMH-2 is commercially available from BASF.
Xiameter PMX-200 is commercially available from Dow Corning. Foam
Ban 149 is commercially available from Munzing.
TABLE-US-00002 TABLE 2 Comparative Comparative Comparative
Comparative Example Example Example 1 Example 2 Example Example
Example 3 Example 4 Component 1 (wt %) 2 (wt %) (wt %) (wt %) 3 (wt
%) 4 (wt %) (wt %) (wt %) Base Oil 1 99.995 99.99 99.995 99.99 (GTL
4) Base Oil 2 99.995 99.99 99.995 99.99 (Yubase 4) PC 1644 0.005
0.01 0.005 0.01 Synative 0.005 0.01 0.005 0.01 AC AMH-2 Total 100
100 100 100 100 100 100 100 ASTM D892 (mL foam): Seq I 0/0 0/0 30/0
30/0 0/0 10/0 20/0 20/0 Seq II 0/0 0/0 0/0 0/0 0/0 0/0 20/0 20/0
Seq III 0/0 0/0 30/0 20/0 0/0 0/0 0/0 10/0 Comparative Comparative
Comparative Comparative Example Example Example 5 Example 6 Example
Example Example 7 Example 8 Component: 5 (wt %) 6 (wt %) (wt %) (wt
%) 7 (wt %) 8 (wt %) (wt %) (wt %) Base Oil 1 99.995 99.99 99.995
99.99 (GTL 4) Base Oil 2 99.995 99.99 99.995 99.99 (Yubase 4)
Xiameter 0.005 0.01 0.005 0.01 PMX-200 Foam Ban 0.005 0.01 0.005
0.01 149 Total 100 100 100 100 100 100 100 100 ASTM D892 (mL foam):
Seq I 0/0 10/0 20/0 20/0 0/0 0/0 10/0 10/0 Seq II 0/0 0/0 20/0 20/0
0/0 0/0 0/0 0/0 Seq III 0/0 0/0 0/0 10/0 0/0 0/0 10/0 10/0
Discussion
[0088] In the foaming test ASTM D892, the lower the amount of foam
produced, the better the anti-foam properties of the composition.
From Table 2 it can be seen that there is a tendency for
Comparative Examples 1-8 (containing Yubase 4) to produce higher
amounts of foam than Examples 1-8 (containing GTL 4).
* * * * *