U.S. patent application number 11/446820 was filed with the patent office on 2006-12-14 for method to synthesize fluorinated zddp.
This patent application is currently assigned to Platinum Research Organization. Invention is credited to Pranesh B. Aswath, Ronald L. Elsenbaumer.
Application Number | 20060281644 11/446820 |
Document ID | / |
Family ID | 38801816 |
Filed Date | 2006-12-14 |
United States Patent
Application |
20060281644 |
Kind Code |
A1 |
Aswath; Pranesh B. ; et
al. |
December 14, 2006 |
Method to synthesize fluorinated ZDDP
Abstract
Disclosed are methods for preparing lubricant additives and
lubricants by reacting together organophosphate compounds and
fluorine compounds, the fluorine compound participating in the
reaction as a reactant. The supernatants and precipitates formed
during the reaction then may be used as lubricant additives.
Inventors: |
Aswath; Pranesh B.;
(Grapevine, TX) ; Elsenbaumer; Ronald L.;
(Arlington, TX) |
Correspondence
Address: |
DALLAS OFFICE OF FULBRIGHT & JAWORSKI L.L.P.
2200 ROSS AVENUE
SUITE 2800
DALLAS
TX
75201-2784
US
|
Assignee: |
Platinum Research
Organization
Dallas
TX
|
Family ID: |
38801816 |
Appl. No.: |
11/446820 |
Filed: |
June 5, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10965686 |
Oct 14, 2004 |
7074745 |
|
|
11446820 |
Jun 5, 2006 |
|
|
|
60511290 |
Oct 15, 2003 |
|
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|
Current U.S.
Class: |
508/369 ;
508/371; 508/419 |
Current CPC
Class: |
C10N 2010/06 20130101;
C10N 2010/14 20130101; C10N 2070/00 20130101; C10M 2223/06
20130101; C10N 2010/12 20130101; C10M 2223/045 20130101; C10N
2010/04 20130101; C10M 2211/04 20130101; C10M 2211/042 20130101;
C10M 2223/043 20130101; C10M 159/123 20130101; C10M 137/00
20130101; C10M 2211/044 20130101; C10M 2223/042 20130101; C10M
2211/02 20130101; C10M 2223/061 20130101; C10N 2010/08 20130101;
C10M 137/10 20130101; C10M 2223/047 20130101; C10M 177/00 20130101;
C10M 2223/04 20130101; C10N 2040/042 20200501; C10M 2223/065
20130101; C10N 2060/08 20130101; C10N 2030/06 20130101; C10M
2201/081 20130101; C10M 2211/00 20130101 |
Class at
Publication: |
508/369 ;
508/419; 508/371 |
International
Class: |
C10M 137/06 20060101
C10M137/06 |
Claims
1. A method for preparing lubricant additives comprising: reacting
one or more phosphorous compounds with one or more halide compounds
wherein said one or more halide compounds participates as a
reactant, wherein supernatants and precipitates resulting from said
reaction form said lubricant additives.
2. The method of claim 1 wherein said one or more halide compounds
is selected from the group consisting of: metal halides,
organohalides, and fluorinating agents.
3. The method of claim 2 wherein said metal halides comprise:
ferric fluoride, aluminum trifluoride, zirconium tetrafluoride,
titanium trifluoride, titanium tetrafluoride, chromium difluoride,
chromium trifluoride, manganese difluoride, manganese trifluoride,
nickel difluoride, stannous difluoride, stannous tetrafluoride, and
combinations thereof.
4. The method of claim 1 wherein said one or more phosphorous
compounds is zinc dialkylthiophosphate (ZDDP).
5. The method of claim 1 wherein said one or more phosphorous
compounds is a mixture of ZDDP with smaller molecular weight
organophosphates.
6. The method of claim 1 wherein said one or more phosphorous
compounds is selected from the group consisting of: ashless
phosphates, thiophosphates, thiostannates, ZDDP, ZDDP mixed with
smaller molecular weight organophosphates, metal organophosphates,
and metal organothiophosphates.
7. The method of claim 1 wherein said reaction occurs at a
temperature ranging from -20.degree. C. to 150.degree. C.
8. The method of claim 1 wherein said reaction occurs at a
temperature ranging from 60.degree. to 150.degree. C.
9. The method of claim 1 wherein said reaction occurs over a period
of time ranging from 20 minutes to 24 hours.
10. A method for synthesizing lubricant additives comprising:
mixing at least one organophosphate compound with at least one
fluorine compound in a mill for a period of time ranging from 10
minutes to 30 days at a temperature ranging from -20.degree. C. to
150.degree. C.; and forming a supernatant and precipitate during
the reaction, wherein said supernatant and said precipitate are
used as said lubricant additives.
11. A method for synthesizing lubricant additives comprising:
combining at least one organophosphate compound with at least one
fluorinating agent; reacting said combination of said at least one
organophosphate compound and said at least one fluorinating agent
at a temperature ranging from -20.degree. C. to 150.degree. C. for
a duration of time ranging from 1 minute to 24 hours, wherein a
solution formed during said reaction, separated from any solids
formed during said reaction results in said lubricant
additives.
12. The method of claim 11, further comprising: adding said
solution formed during said reaction to a fully formulated GF-4
oil, automatic transmission fluid, gear oil or grease.
13. A method for preparing lubricant additives comprising: mixing
ferric fluoride with one or more organophosphates; baking said
mixture of ferric fluoride and said one or more organophosphates;
centrifuging said mixture, wherein the decant formed is a
fluorinated organophosphate compound to be utilized as lubricant
additives.
14. The method of claim 13 wherein said one or more
organophosphates is ZDDP.
15. The method of claim 13 wherein said baking step is performed in
an inert environment.
16. The method of claim 13 wherein said baking step is performed in
an air environment.
17. The method of claim 13 wherein said baking occurs at
temperatures between -20.degree. C. and 150.degree. C.
18. The method of claim 13 wherein said baking occurs for a period
of time ranging from 20 minutes to 3 days.
19. The method of claim 13 said method further comprising: using an
attrition milling process to break up particles of said ferric
fluoride and enhance the interaction between said ferric fluoride
and said one or more organophosphates to produce a fluorinated
organophosphate compound.
20. The method of claim 19 wherein said attrition milling process
utilizes a ball mill.
21. The method of claim 19 wherein said attrition milling process
utilizes a stirred ball bill.
22. The method of claim 19 wherein attrition milling process
utilizes a centrifugal or planetary ball mill.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to U.S. provisional
patent application Ser. No. 60/511,290 filed on Oct. 15, 2003,
entitled "ENGINE OIL ADDITIVE," and co-pending, commonly assigned,
U.S. patent application Ser. No. 10/965,686 filed Oct. 14, 2004,
entitled "Engine Oil Additive,", the disclosures of which are
hereby incorporated by reference herein.
TECHNICAL FIELD
[0002] The present application relates generally to lubricants, and
more particularly, to synthesis of fluorinated zinc
dialkyldithiophosphate (ZDDP).
BACKGROUND OF THE INVENTION
[0003] Lubricants comprise a variety of compounds selected for
desirable characteristics such as anti-wear and anti-friction
properties. Many of these compounds are used in enormous
quantities. For example, more than four billion quarts of crankcase
oil are used in the United States per year. However, many compounds
currently in use also have undesirable characteristics. Currently
available crankcase oils generally include the anti-wear additive
zinc dialkyldiothiophosphate (ZDDP), which contains phosphorous and
sulfur. Phosphorous and sulfur poison catalytic converters causing
increased automotive emissions. It is expected that the EPA
eventually will mandate the total elimination of ZDDP or will allow
only extremely low levels of ZDDP in crankcase oil. However, no
acceptable anti-wear additives to replace ZDDP or to modify ZDDP to
have more desirable characteristics are currently available.
[0004] It is an object of the present invention to provide
environmentally friendly lubricants, wherein the amounts of
phosphorous and sulfur in the lubricants are significantly reduced
and approach zero. It is another object of the present invention to
produce lubricants with desirable anti-wear and anti-friction
characteristics.
BRIEF SUMMARY OF THE INVENTION
[0005] Embodiments of the current invention are several methods for
preparing lubricant additives and lubricants by reacting together
organophosphates and organothiophosphates and their derivatives,
such as zinc dialkyldithiophosphate (ZDDP), and fluorine compounds,
such as metal fluorides, organoflourides and fluorinating agents.
Certain embodiments of the invention comprise methods for preparing
lubricant additives by reacting at least one organophosphate
compound and at least one fluorinating agent wherein the at least
one of the fluorinating agent participates in the reaction
primarily as a reactant. Organophosphates used in embodiments of
the invention may comprise metal organophosphates, ashless
organothiophosphates, metal organothiophosphates, and other
compounds comprising organophosphate groups. The organophosphate
used in a preferred embodiment is a metal organophosphate, such as
ZDDP. In other embodiments, one of the organophosphate compounds
used is ZDDP mixed with smaller molecular weight organophosphates.
Other embodiments include ashless phosphates, thiophosphates,
thiostanates, and the like.
[0006] In one embodiment, at least one organophosphate and at least
one metal fluoride are reacted together at about -20.degree. C. to
about 150.degree. C. In a preferred embodiment, the reactant
mixture is heated to a temperature of about 60.degree. C. to about
150.degree. C. The reaction is allowed to continue from about 20
minutes to about 24 hours. Both supernatants and precipitates
formed during the reaction may be used as lubricant additives in
certain embodiments of the present invention.
[0007] In a second embodiment, at least one organophosphate,
ashless organothiophosphate, metal organothiophosphate, or a
derivative thereof, and at least one metal fluoride and/or
organofluoride are mixed together in a ball mill, centrifugal mill,
rotary mill, vibratory mill, planetary mill and/or attrition mill
together with milling media that may constitute steel balls,
tungsten carbide, ceramic balls such as alumina, zirconia, silicon
carbide, silicon nitride among other ceramics. The mixture is
milled between 10 minutes and 30 days depending on the method used
and the temperature is held between -20.degree. C. and 150.degree.
C. In a preferred embodiment, the mixture is milled at room
temperature for a period between 72 hrs and 168 hours. Both the
supernatant and the precipitates formed during the reaction may be
used as lubricant additives in certain embodiments of the present
invention.
[0008] In a third embodiment, at least one organophosphate, ashless
organothiophosphate, metal organothiophosphate, or a derivative
thereof, and at least one fluorinating agent are mixed together and
the reaction is conducted at temperatures between -20 to
150.degree. C. for durations ranging from 1 minute to 24 hours. The
solution formed during the reaction, separated from any solids
present during the reaction, if any, may be used as lubricant
additives in certain embodiments of the present invention.
[0009] In a preferred embodiment, the liquid product, separated
from any solids present formed in any of the above mentioned
processes is added to fully formulated GF-4 oil, automatic
transmission fluid, gear oils and/or greases.
[0010] The foregoing has outlined rather broadly the features and
technical advantages of the present invention in order that the
detailed description of the invention that follows may be better
understood. Additional features and advantages of the invention
will be described hereinafter which form the subject of the claims
of the invention. It should be appreciated by those skilled in the
art that the conception and specific embodiment disclosed may be
readily utilized as a basis for modifying or designing other
structures for carrying out the same purposes of the present
invention. It should also be realized by those skilled in the art
that such equivalent constructions do not depart from the spirit
and scope of the invention as set forth in the appended claims. The
novel features which are believed to be characteristic of the
invention, both as to its organization and method of operation,
together with further objects and advantages will be better
understood from the following description when considered in
connection with the accompanying figures. It is to be expressly
understood, however, that each of the figures is provided for the
purpose of illustration and description only and is not intended as
a definition of the limits of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] For a more complete understanding of the present invention,
reference is now made to the following descriptions taken in
conjunction with the accompanying drawings, in which:
[0012] FIG. 1 is a table showing representative organophosphate
compounds that may be used with embodiments of the present
invention;
[0013] FIGS. 2A-2C show structures associated with some of the
organophosphates that may be used with embodiments of the present
invention;
[0014] FIG. 3 is a table presenting experimental results showing
the presence of fluorine in reaction supernatants;
[0015] FIG. 4 shows a 31P NMR spectra of supernatant from a
reaction between ZDDP and ferric fluoride;
[0016] FIG. 5 is a 31P NMR spectrum of supernatant from a reaction
between ZDDP and ferric fluoride;
[0017] FIG. 6 is another 31P NMR spectrum of supernatant from a
reaction between ZDDP and ferric fluoride;
[0018] FIGS. 7-10 show organophosphate structures that may be used
with embodiments of the present invention;
[0019] FIG. 11A is 31P NMR spectrum of supernatant from a reaction
between ZDDP and ferric fluoride by Ball milling for 24 hours;
[0020] FIG. 11B is a 31P NMR spectrum of supernatant from a
reaction between ZDDP and ferric fluoride by Ball milling for 72
hours; and
[0021] FIG. 12 illustrates a profilometric wear volume result
comparison of lubricant oils to which were added ZDDP alone,
supernatant from ZDDP and ferric fluoride that were combined, but
not heated, and supernatant from ZDDP and ferric fluoride that were
combined and heated at 150.degree. C. for 20 minutes.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Embodiments of the present invention provide low phosphorous
lubricants comprising improved lubricant additives. Lubricant
additives according to embodiments of the present invention may be
added to lubricants including, but not limited to, greases,
crankcase oils, and hydrocarbon solvents comprising from about 0.01
weight percent phosphorous to about 0.1 weight percent phosphorous.
In a preferred embodiment of the present invention, lubricant
additives are mixed with a fully formulated engine oil without
ZDDP. The term "fully formulated oil" as used herein to illustrate
certain embodiments of the present invention is used to describe
engine oils that include additives, but not zinc
dialkyldithiophosphate (ZDDP), and comprise from about 0.01 weight
percent phosphorous to about 0.1 weight percent phosphorous. In
certain embodiments, the fully formulated oil may be, for example,
a GF4 oil with an additive package comprising standard additives,
such as dispersants, detergents, and anti-oxidants, but without
ZDDP or its derivatives.
[0023] Certain embodiments of the present invention comprise
methods for preparing lubricant additives to be added to low
phosphorous lubricant bases by reacting together one or more
organophosphates, including but not limited to metal
organophosphates such as ZDDP, and one or more metal halides, such
as ferric fluoride, wherein the metal halide participates in the
reaction primarily as a reactant. Metal halides preferably used
with embodiments of the present invention include, for example,
aluminum trifluoride, zirconium tetrafluoride, titanium
trifluoride, titanium tetrafluoride, and combinations thereof. In
other embodiments, transition metal halides are used, such as, for
example, chromium difluoride, chromium trifluoride, manganese
difluoride, manganese trifluoride, nickel difluoride, stannous
difluoride, stannous tetrafluoride, and combinations thereof.
Ferric fluoride is preferably used in a preferred embodiment of the
present invention. Ferric fluoride may be produced according to a
process described in co-pending U.S. patent application Ser. No.
10/662,992 filed Sep. 15, 2003, the contents of which are herein
incorporated by reference.
[0024] In a first embodiment, ferric fluoride is mixed with one or
more of the organophosphates, such as ZDDP, and baked in an inert
environment, such as argon or nitrogen, or an air environment at
temperatures between -20 and 150.degree. C. for a period of time
ranging from 20 minutes to several days. Preferably, the mixture is
baked at 80.degree. C. for 1 hour. The product is centrifuged, and
the decant is a fluorinated organothiophosphate compound and to be
utilized as an additive at phosphorous levels between 0.01 and 0.1
wt. % P in GF-4 oils.
[0025] In another embodiment, ferric fluoride is mixed with ZDDP
and subjected to an attrition milling process. In an attrition
mill, kinetic and mechanical energy of the milling media is used to
break up particles of ferric fluoride and enhance the interaction
between the ferric fluoride and the ZDDP, thiophosphate or
organophosphate to produce a fluorinated ZDDP, fluorinated
thiophosphate, or fluorinated organophosphate compound
respectively. There are several types of attrition mills that can
be used which are well known in the art.
[0026] In the first method a ball mill preferably may be used
wherein milling media made up of balls of tungsten carbide,
alumina, zirconia, stainless steel, silicon carbide or silicon
nitride, for example, are tumbled together with ferric fluoride and
ZDDP in a cylindrical container for a period of 24-300 hours at
temperatures between -20 and 150.degree. C. In a preferred
embodiment a mixture of ZDDP and ferric fluoride in the ratio of
1:0.4 is ball milled for a period of 168 hours at room temperature.
The reaction product is centrifuged to separate out the unreacted
ferric fluoride as well as any other solid reaction products from
the decant that comprises fluorinated ZDDP. The recovered unreacted
ferric fluoride can then be mixed with a new batch of ZDDP and then
ball milled to yield a new batch of fluorinated ZDDP. The ferric
fluoride may be recycled 2-10 times before the reactivity of the
ferric fluoride diminishes to the point where it may be no longer
useful.
[0027] In another method of attrition milling, an Attritor (which
is often referred to generically as a "stirred ball mill") may be
used. The operation of an Attritor is simple and effective. The
material to be ground is placed in a stationary tank with the
grinding media. Carbon steel, stainless steel, chrome steel,
tungsten carbide and ceramic balls are preferably used as grinding
media. The material to be ground and the grinding media are then
agitated by a shaft with arms, rotating at high speed. The
agitation at high speed result in the grinding media exerting both
shearing and impact forces on the material. The final result of
this efficient process is an extremely fine material, measured in
microns or fractions of microns, when distributed on a very narrow
curve. It should be appreciated that a laboratory Attritor works up
to ten times faster than the conventional ball, pebble or jar mill.
In this mill the ferric fluoride and ZDDP is added and milled
together for periods between 20 minutes and 168 hours. The reaction
product is centrifuged and the decant is separated out and used in
liquid form as fluorinated ZDDP. The solids remaining comprise
recyclable active ferric fluoride. This process preferably may be
repeated at least 2-10 times to repeat the fluorination process
using the recycled ferric fluroide.
[0028] In a further method, a centrifugal or planetary ball mill is
preferably used. With a planetary ball mill, the material to be
milled is placed in a chamber together with the milling media and
the chamber is rotated such that the balls cascade against each
other and collide with maximum energy against the opposite wall.
Carbon steel, stainless steel, chrome steel, tungsten carbide and
ceramic balls are preferably used milling media. Using this type of
ball mill, ferric fluoride and ZDDP are added and milled together
for periods ranging from 20 minutes to 168 hours. The reaction
product is centrifuged and the decant is separated out and used in
liquid form as fluorinated ZDDP. The remaining solids comprise
recyclable recovered ferric fluoride. This process can be repeated
at least 2-10 times to repeat the fluorination process using the
recycled ferric fluoride.
[0029] Fluorination of ZDDP and other phosphorous and
thiophosphorous compounds can also be preferably conducted by
reacting these types of compounds with a fluorinating agent.
Fluorinating agents are a class of fluorine containing compounds
that can easily donate a fluorine atom to the acceptor molecule
thereby forming a new fluorinated compound. There are numerous
fluorinating agents; however, as listed in the table below, some of
the more commonly used fluorinating agents include, but are not
limited to: TABLE-US-00001 diatomic fluorine gas (F.sub.2)
hydrofluoric acid (HF) bromine pentafluoride (BrF.sub.5) sulfur
hexafluoride (SF.sub.6) dioxygen difluoride (O.sub.2F.sub.2)
dioxygen monofluoride (O.sub.2F) sulfuryl difluoride
(SO.sub.2F.sub.2) 3,3,3 trifluoropropionic acid
(CF.sub.3--CH.sub.2--COOH) pentafluoropropionic acid
(CF.sub.3--CF.sub.2--COOH) trifluoroacetic acid, 2,2,3,3,3-
pentafluoropropyl-.alpha.-fluoroacrylate
(CH.sub.2.dbd.CF--COOCH.sub.2CF.sub.2CF.sub.3)
,2,3,3,3-pentafluoropropyl-methacrylate
2,2,2,3,3-tetrafluoropropyl-.alpha.-fluoroacrylate
(CH.sub.2.dbd.C(CH.sub.3)--COOCH.sub.2--CF.sub.2--CF.sub.3)
(CH.sub.2.dbd.CF--COOCH.sub.2CF.sub.2CF.sub.2H)
2,2,3,3,3-pentafluoropropanol 2,2,3,3-tetrafluoropropanol
(CF.sub.3--CF.sub.2--CH.sub.2OH) (CF.sub.2H--CF.sub.2--CH.sub.2OH)
2,2,3,4,4,4-hexafluoro-1-butanol dichloro-2,2,2-trifluoroethane
(CF.sub.3--CHF--CF.sub.2--CH.sub.2OH) (CF.sub.3--CHCI.sub.2) 2-iodo
heptafluoropropane (CF.sub.3--CFI--CF.sub.3)
2,2,2-trifluoroacetamide difluoroacetic acid ethylester
difluoroacetic acid methylester, trifluoroacetic acid
isopropylester 1,1,1-Trifluoroacetone, (CF3COOCH(CH3)2)
heptafluoroisopropyltrifluoromethyl ketone (CF3--C(O)--CF(CF3)2)
hexafluoropropyl-methyl ketone
bis-(2-methoxyethyl)aminosulfur-trifluoride
(CH3--C(O)--CF2--CHF--CF3) diethylaminosulfur trifluoride pyridine
HF 1-chloromethyl-4-fluoro-1,4- 1-methyl-4-fluoro-1,4-
diazoniabicyclo[2.2.2]octane bis- diazoniabicyclo[2.2.2]octane Bis-
(tetrafluoroborate) (tetrafluoroborate) N-fluoropyridinum triflate
N-fluoro[1,3,2]dithiazinane-1,1,3,3-tetraoxide
N-fluoromethanesulfonimide n-Bu.sub.4NHF.sub.2, N-fluoropyridinium
trifluoromethanesulfonate
E1-fluoro-2,4,6-trimethoxy-1,3,5-triazinium
pentafluorophenyldifluoroxenonium(IV) hexafluoroantimonate
tetrafluoroborate triethylamine polyhydrofluoride tri-n-butylamine
polyhydrofluoride
[0030] The list of fluorinating agents in the table above, while
extensive is not exhaustive, and it should be appreciated that
there are other fluorine-containing compounds that can serve as
fluorinating agents. These compounds when reacted with ZDDP,
organophosphate or organothiophosphate, or metal derivatives
thereof, or other derivatives thereof, result in fluorine transfer
from the fluorinating agent to the ZDDP, organophosphate or
organothiophosphate compound in the form of a P--F bond yielding a
fluorinated organothiophosphate compound. Further reactions provide
additional fluorination and formation of C--F bonds on the alkyl
side chains in the phosphate compounds.
[0031] FIG. 1 is a table showing several of the organophosphate
compounds that may be used with embodiments of the present
invention. Generally, dithiophosphates and amine and amine salts of
monothiophosphates and dithiophosphates may preferably be used.
Other organophosphates listed in FIG. 1 include neutral ZDDP
(primary); neutral ZDDP (secondary); basic ZDDP; (RS).sub.3P(s)
where R>CH.sub.3; (RO)(R'S)P(O)SZn--; (RO).sub.2(RS)PS where
R>CH.sub.3; P(S)SZn--; (RO).sub.2P(S)(SR); R(R'S).sub.2PS where
R=CH.sub.3 and R'>CH.sub.3; (RO).sub.3PS where R=CH.sub.3 and
R'=alkyl; MeP(S)Cl.sub.2; (RO).sub.2(S)PSP(S)(OR).sub.2; P(S)(SH);
(RO)(R'S)P(O)SZn--, SPH(OCH.sub.3).sub.2, where R=any alkyl and
R'=any alkyl, and combinations thereof. The chemical structures of
representative compounds from FIG. 1 and additional organophosphate
compounds that may be used with the invention are shown in FIGS.
2a-2c. In certain embodiments of the present invention,
organophosphates not shown in FIGS. 1 and 2a-2c preferably may be
used. The organophosphate ZDDP is used in preferred embodiments of
the present invention. Embodiments using ZDDP, alone or in
combination with other organophosphates, can utilize ZDDP in one or
more moieties. Preferably, the ZDDP used is the neutral or basic
moiety. Some of the ZDDP moieties are shown in FIG. 2a as
structures 1 and 5.
[0032] FIG. 3 is a table presenting experimental results
demonstrating that fluorine, presumably donated by the metal
halide, ferric fluoride, remains in a reaction supernatant formed
using an embodiment of the present invention. In this experiment,
samples of untreated ZDDP, treated ZDDP under an inert atmosphere,
and ZDDP reacted with ferric fluoride under an inert atmosphere
were chemically analyzed. The ASTM D3120 protocol was used for
sulfur and ASTM D5185 for phosphorous, zinc, and iron. Fluorine
analysis was conducted separately by completely combusting to a
fluoride and using iron chromatography. The results of the analysis
shown in FIG. 3 indicate that no fluorine was present in the
supernatant samples from either the untreated ZDDP or the treated
ZDDP under inert atmosphere. However, significant quantities of
fluorine (163 parts per million) were found in supernatant samples
taken from the ZDDP reacted with ferric fluoride. Also, iron levels
were extremely low (1-2 parts per million) in those supernatant
samples, indicating that the fluorine present in the supernatant
has bonded to an element other than iron.
[0033] FIG. 4 shows a 31P NMR spectrum of supernatant from a
reaction between ZDDP and ferric fluoride. The spectra shows the
presence of doublets resulting from the interaction of bound
phosphorous and fluorine atoms in compounds present in the
supernatant sample. The experiments summarized in FIGS. 3 and 4
illustrate that the metal halide participates primarily as a
reactant in embodiments of the present invention.
[0034] FIGS. 5-10 show experimental results and possible structures
for reaction products formed by embodiments of the present
invention. FIG. 5 is a 31P NMR spectrum (1H decoupled to suppress
phosphorous-hydrogen peaks) of supernatant from a reaction between
ZDDP and ferric fluoride showing the formation of a
fluoro-phosphorous compound. A triplet located at approximately 57
ppm and 66 ppm are due to a phosphorous-fluorine bond with J=1080.
Each triplet peak is composed of multiple peaks that are apparent
triplets.
[0035] FIG. 6 is a 31P NMR spectrum (19F decoupled to suppress
phosphorous-fluorine peaks) of supernatant from a reaction between
ZDDP and ferric fluoride. Comparison with FIG. 5 shows that the
triplets present in FIG. 5 have merged to a single triplet at
approximately 61 ppm located midway between the former triplet
locations at approximately 57 ppm and 66 ppm. The merging of the
two triplets indicates that the origin of the triplets in FIG. 5
was from a phosphorous-fluorine bond. Also, the fact that a triplet
still remains in this spectrum indicates that the origin of the
triplet is from a phosphorous-phosphorous backbone as opposed to
from a phosphorous-hydrogen or phosphorous-fluorine backbone.
[0036] The three peaks in the triplets of FIGS. 5 and 6 can be from
spin-spin splits from at least three different interacting
phosphorous atoms in the same structure. Chemical shifts of three
phosphorous atoms are nearly the same, such that relative chemical
shifts are less than or equal to coupling constants of the
phosphorous, i.e. the origin of the shifts result from a second
order spectra rather than a first order. Four possible compounds
that can produce the NMR spectra of FIGS. 5 and 6 are shown in FIG.
7. In all structures shown in FIG. 7, X=R, OR, and/or SR. R refers
to an alkyl group, and may be the same or different at the same
time within the same structure. The O(S) refers to either an oxygen
or sulfur atom being present at one time. Y refers to F or another
halogen. However, it should be appreciated that at least one Y
present in the structure will be equal to F.
[0037] If the peaks in the triplets of FIGS. 5 and 6 are not
arising from a phosphorous-phosphorous backbone, then chemical
structures such as those shown in FIG. 8 may be responsible for the
spectra. In the case of structures (a)-(c) shown in FIG. 8, the
origin of the multiple peaks in the spectra may preferably result
from the different environment surrounding the phosphorous atoms.
In structure (d) shown in FIG. 8, the separation of the phosphorous
atoms is large enough to suppress any interaction between them and
the origin of the multiple peaks in the spectra results from the
different environment surrounding the phosphorous atoms. In all of
the structures shown in FIG. 8, the presence of a
phosphorous-fluorine bond has been confirmed. In each of the
structures shown in FIG. 8, R is equal to an alkyl group.
[0038] If two of the shoulder peaks in the NMR triplets shown in
FIGS. 5 and 6 arise from spin-spin coupling of two phosphorous
atoms on the backbone, then the third dominant peak at the center
may arise from any one of the compounds shown in FIG. 8. The
shoulder peaks (smaller peaks within FIGS. 5 and 6) arise from the
structure of the kind shown in FIG. 9. The dominant peak (the
middle peak) can arise from any one of the three structures (a),
(b) or (c) shown in FIG. 8.
[0039] FIG. 10 shows additional organophosphate compounds that can
be used with embodiments of the present invention. The
organophosphate structures should be appreciated as representative
structures and not considered to be in any way limiting this
invention to these structures. Many embodiments of this invention
use organophosphate structures that may not be specifically
illustrated in FIG. 10.
[0040] FIG. 11(a) is a 31P NMR spectrum (1H decoupled to suppress
phosphorous-hydrogen peaks) of supernatant from a reaction between
ZDDP and ferric fluoride showing the formation of a
fluoro-phosphorous compound. This reaction preferably occurred when
ZDDP and ferric fluoride were mixed together and milled for a
period of 24 hours in a rotary ball mill. A doublet located at
approximately 57 ppm and 66 ppm is due to a phosphorous-fluorine
bond with J=1080. Each doublet peak is composed of multiple peaks
that are apparent triplets.
[0041] FIG. 11(b) is a 31P NMR spectrum (1H decoupled to suppress
phosphorous-hydrogen peaks) of supernatant from a reaction between
ZDDP and ferric fluoride showing the formation of a
fluoro-phosphorous compound. This reaction occurred when ZDDP and
ferric fluoride were mixed together and milled for a period of 72
hours in a rotary ball mill. A doublet located at approximately 57
ppm and 66 ppm is due to a phosphorous-fluorine bond with J=1080.
Each doublet peak is composed of multiple peaks that are apparent
triplets.
[0042] Experiments were performed to evaluate low phosphorous
lubricant formulations comprising lubricant additives produced
according to embodiments of the invention. Generally, wear volume
comparisons were used to compare the lubricants and lubricant
additives produced according to embodiments of the invention. The
experiments were conducted on a modified Ball on Cylinder machine.
The machine was modified to accept standard Timken Roller Tapered
Bearings, where the outer surface of the cup was used for wear
testing. In order to preferably generate consistent results, a
protocol was established to prepare the surface prior to wear
testing. The protocol comprises two phases: break-in and actual
test.
[0043] The break-in protocol begins with preparation of the ring
and the ball by cleaning with hexane and acetone followed by
brushing. Then 50 .mu.L of break in oil comprising base oil is
applied to the center of the surface of the ring. For 2000 cycles,
a constant load of 6 kg is applied. The rotation is then stopped,
and the ring and the ball cleaned on the spot without removing
them.
[0044] For the actual test, the lubricant being tested is applied
to the center of the surface of the ring. As with break in, a
constant load of 6 kg is applied for the first 500 cycles. For the
next 1500 cycles, the load is gradually increased to 24 kg. The
weight used for the protocol may vary in some tests. Up to 23000
additional cycles at 700 rpm may be used in certain variations of
the protocol during which the load is applied constantly and data
acquisition is performed.
[0045] FIG. 12 illustrates a profilometric wear volume result
comparison of lubricant oils to which were added ZDDP alone,
supernatant from ZDDP and ferric fluoride that were combined, but
not heated, and supernatant from ZDDP and ferric fluoride that were
combined and heated at 150.degree. C. for 20 minutes. The data from
the experiment shows that there is a greater than 50% reduction in
wear volume when comparing the addition of ZDDP alone to the
addition of supernatant produced by reacting ZDDP and ferric
fluoride with heat. The experiment also shows that the reaction
between ZDDP and ferric fluoride appears to progress at room
temperature, as there was a significant reduction in wear volume
when using the room temperature supernatant with a lubricant oil.
The results show that the lubricant oil comprising lubricant
additive produced according to an embodiment of the present
invention is superior in minimizing the wear volume of a bearing
used in the modified Ball on Cylinder test described above.
[0046] Although the present invention and its advantages have been
described in detail, it should be understood that various changes,
substitutions and alterations can be made herein without departing
from the spirit and scope of the invention as defined by the
appended claims. Moreover, the scope of the present application is
not intended to be limited to the particular embodiments of the
process, machine, manufacture, composition of matter, means,
methods and steps described in the specification. As one of
ordinary skill in the art will readily appreciate from the
disclosure of the present invention, processes, machines,
manufacture, compositions of matter, means, methods, or steps,
presently existing or later to be developed that perform
substantially the same function or achieve substantially the same
result as the corresponding embodiments described herein may be
utilized according to the present invention. Accordingly, the
appended claims are intended to include within their scope such
processes, machines, manufacture, compositions of matter, means,
methods, or steps.
* * * * *