U.S. patent application number 11/049812 was filed with the patent office on 2005-06-16 for lubricity additives for low sulfur hydrocarbon fuels.
This patent application is currently assigned to BetzDearborn, Inc.. Invention is credited to Chang, Zen-Yu, Cross, Collin W., Goliaszewski, Alan E., Pruett, S. Blake.
Application Number | 20050126073 11/049812 |
Document ID | / |
Family ID | 30115129 |
Filed Date | 2005-06-16 |
United States Patent
Application |
20050126073 |
Kind Code |
A1 |
Cross, Collin W. ; et
al. |
June 16, 2005 |
Lubricity additives for low sulfur hydrocarbon fuels
Abstract
The present invention relates to additives for enhancing the
lubricity of hydrocarbon fuel oils, the inventive additive
composition including one or more of the reaction products of (i)
an alkylated polyamine and (ii) urea or isocyanate, or the salt
adducts of these reaction products. More particularly, the present
invention provides for a process for improving the lubricity of
hydrocarbon fuel oils, which are low in inherent lubricity due to
treatment to reduce sulfur and aromatic components for improved
emissions.
Inventors: |
Cross, Collin W.; (Houston,
TX) ; Chang, Zen-Yu; (Hockessin, DE) ; Pruett,
S. Blake; (Montgomery, TX) ; Goliaszewski, Alan
E.; (Woodlands, TX) |
Correspondence
Address: |
HOFFMANN & BARON, LLP
6900 JERICHO TURNPIKE
SYOSSET
NY
11791
US
|
Assignee: |
BetzDearborn, Inc.
|
Family ID: |
30115129 |
Appl. No.: |
11/049812 |
Filed: |
February 3, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11049812 |
Feb 3, 2005 |
|
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|
10197307 |
Jul 16, 2002 |
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6872230 |
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Current U.S.
Class: |
44/417 |
Current CPC
Class: |
C10L 10/08 20130101;
C10L 1/232 20130101; C10L 1/14 20130101; C10L 1/2227 20130101 |
Class at
Publication: |
044/417 |
International
Class: |
C10L 001/22 |
Claims
What is claimed is:
1. A hydrocarbon fuel oil composition comprising: (a) a hydrocarbon
fuel oil; and (b) a lubricity additive comprising one or more of
the reaction products of (i) an alkylated polyamine and (ii) urea
or isocyanate, or the salt adducts of said reaction products.
2. The composition of claim 1, wherein said additive comprises a
compound of the following formula (Formula I): 7wherein R.sub.1 is
a hydrocarbyl group from C.sub.8-30; R.sub.2 is hydrogen, a
hydrocarbyl group from C.sub.8-30, or the group Y; R.sub.3 is each
independently hydrogen, a hydrocarbyl group from C.sub.8-30, or
(CH.sub.2).sub.qOH; R.sub.4 is hydrogen, a hydrocarbyl group from
C.sub.8-30, (CH.sub.2).sub.qOH, or the group Y; x is from 2-6 and n
is from 1 to 6, or mixtures thereof; q is from 1 to 6; and Y is as
follows wherein R.sub.3 is as defined above: 8
3. The composition of claim 1, wherein said additive comprises a
compound of the following formula (Formula II): 9wherein R.sub.1 is
a hydrocarbyl group from C.sub.8-30; R.sub.2 is each independently
hydrogen, a hydrocarbyl group from C.sub.8-30, or the group Y;
R.sub.3 is each independently hydrogen, a hydrocarbyl group from
C.sub.8-30, or (CH.sub.2).sub.qOH; R.sub.5 is each independently
hydrogen, a hydrocarbyl group from C.sub.8-30, or
(CH.sub.2).sub.qOH; x is from 2-6 and n is from 1 to 6, or mixtures
thereof; q is from 1 to 6; and Y is as follows wherein R.sub.3 is
as defined above: 10
4. The composition of claim 1, wherein said additive further
comprises a compound of the following formula (Formula III):
11wherein R.sub.1 is a hydrocarbyl group from C.sub.8-30; and
R.sub.6 is hydrogen, or a hydrocarbyl group from C.sub.8-30.
5. The composition of claim 1, wherein said hydrocarbon fuel oil
contains less than 0.2% by weight of sulfur, based on the weight of
said fuel oil.
6. The composition of claim 1, wherein said additive is present in
said fuel oil composition in an amount of about 5 to about 5000 ppm
by weight per weight of said hydrocarbon fuel oil.
7. The composition of claim 1, wherein said additive is present in
an amount of about 50 to about 300 ppm by weight per weight of said
hydrocarbon fuel oil.
8. The composition of claim 1, wherein the alkylated polyamine is
N-alkyldiaminopropane.
9. The composition of claim 1, where said hydrocarbon fuel oil is a
diesel fuel.
10. A hydrocarbon fuel oil composition comprising: (a) a
hydrocarbon fuel oil; and (b) one or more cyclic or open chain urea
derivatives formed from an alkylene polyamine.
11. The composition of claim 10, wherein the alkylene polyamine is
N-alkyldiaminopropane.
12. The composition of claim 10, wherein said open chain urea
derivatives comprise a compound of the following formula, or a salt
adduct thereof: 12wherein R.sub.1 is a hydrocarbyl group from
C.sub.8-30; R.sub.2 is hydrogen, a hydrocarbyl group from
C.sub.8-30, or the group Y; R.sub.3 is each independently hydrogen,
a hydrocarbyl group from C.sub.8-30, or (CH.sub.2).sub.qOH; R.sub.4
is hydrogen, a hydrocarbyl group from C.sub.8-30,
(CH.sub.2).sub.qOH, or the group Y; x is from 2-6 and n is from 1
to 6, or mixtures thereof; q is from 1 to 6; and Y is as follows
wherein R.sub.3 is as defined above: 13
13. The composition of claim 10, wherein said open chain urea
derivatives comprise a compound of the following formula, or a salt
adduct thereof: 14wherein R.sub.1 is a hydrocarbyl group from
C.sub.8-30; R.sub.2 is each independently hydrogen, a hydrocarbyl
group from C.sub.8-30, or the group Y; R.sub.3 is each
independently hydrogen, a hydrocarbyl group from C.sub.8-30, or
(CH.sub.2).sub.qOH; R.sub.5 is each independently hydrogen, a
hydrocarbyl group from C.sub.8-30, or (CH.sub.2).sub.qOH; x is from
2-6 and n is from 1 to 6, or mixtures thereof; q is from 1 to 6 and
Y is as follows wherein R.sub.3 is as defined above: 15
14. The composition of claim 10, wherein said cyclic urea
derivatives comprise a compound of the following formula, or a salt
adduct thereof: 16wherein R.sub.1 is a hydrocarbyl group from
C.sub.8-30; and R.sub.6 is hydrogen, or a hydrocarbyl group from
C.sub.8-30.
15. The composition of claim 10, wherein said additive comprises a
mixture of the compounds of Formulae I, II, and III or the salt
adducts of said mixture: 17wherein R.sub.1 is a hydrocarbyl group
from C.sub.8-30; R.sub.2 is each independently hydrogen, a
hydrocarbyl group from C.sub.8-30 or the group Y; R.sub.3 is each
independently hydrogen, a hydrocarbyl group from C.sub.8-30, or
(CH.sub.2).sub.qOH; R.sub.4 is hydrogen, a hydrocarbyl group from
C.sub.8-30, (CH.sub.2).sub.qOH, or the group Y; R.sub.5 is each
independently hydrogen, a hydrocarbyl group from C.sub.8-30, or
(CH.sub.2).sub.qOH; x is from 2-6 and n is from 1 to 6, or mixtures
thereof; q is from 1 to 6; R.sub.6 is hydrogen, or a hydrocarbyl
group from C.sub.8-30; and Y is as follows wherein R.sub.3 is as
defined above: 18
16. The composition of claim 10, wherein said hydrocarbon fuel oil
contains less than 0.2% by weight of sulfur, based on the weight of
said fuel oil.
17. The composition of claim 10, wherein said additive is present
in an amount of about 50 to about 300 ppm by weight per weight of
said hydrocarbon fuel oil.
18. The composition of claim 10, wherein said hydrocarbon fuel oil
is a diesel fuel.
19. An additive composition for increasing the lubricity of a
hydrocarbon fuel oil comprising at least one reaction product of
(i) an alkylated polyamine and (ii) urea or isocyanate, or a salt
adduct of said reaction product.
20. The additive composition of claim 19, wherein said at least one
reaction product comprises a compound of Formula I, or a salt
adduct thereof.
21. The additive composition of claim 19, wherein said at least one
reaction product comprises a compound of Formula II, or a salt
adduct thereof.
22. The additive composition of claim 19, wherein said at least one
reaction product comprises a compound of Formula III, or a salt
adduct thereof.
23. An additive composition for increasing the lubricity of a
hydrocarbon fuel oil comprising one or more cyclic or open chain
urea derivatives formed from an alkylene polyamine.
24. The additive composition of claim 23, wherein said alkylene
polyamine is N-alkyldiaminopropane.
25. A method of making an additive composition for enhancing the
lubricity of a hydrocarbon fuel oil comprising reacting (i) an
alkylated polyamine and (ii) urea or isocyanate under conditions to
form a compound of Formula I.
26. The method of claim 25, wherein components (i) and (ii) are
reacted under conditions to additionally form a compound of Formula
II.
27. The method of claim 26, wherein components (i) and (ii) are
reacted under conditions to additionally form a compound of Formula
III.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 10/197,307, filed Jul. 16, 2002.
FIELD OF THE INVENTION
[0002] The present invention provides for hydrocarbon fuel oil
compositions, which have as a component an additive for improving
the lubricity of the fuel oil and reducing engine system wear. In
particular, this invention provides for the use of the reaction
products of (i) an alkylated polyamine and (ii) urea or isocyanate,
or the salt adducts of these reaction products, as additives for
improving the lubricity of distillate fuels, which are low in
inherent lubricity due to treatment to reduce the sulfur and/or
aromatic content.
BACKGROUND OF THE INVENTION
[0003] Regulatory agencies have mandated a reduction in the sulfur,
aromatic, and hetero-atom content of commercial diesel and
distillate fuels in an effort to improve emissions characteristics
of the fuels. This regulatory requirement causes a problem insofar
as the fuel industry recognizes that the refining processes needed
to produce these fuels require a more severe hydrotreatment which
removes polar species from the fuel and reduces its lubricity.
Reducing the level of one or more of the sulfur, polynuclear
aromatic or polar components of diesel fuel oil can reduce the
ability of the oil to lubricate the injection system of the engine,
causing the fuel injection pump of the engine to fail prematurely.
Even marginally lower lubricity can significantly increase wear of
fuel pumps, valves and injector nozzles over an extended period of
use.
[0004] The problem of poor lubricity in these fuels is likely to be
exacerbated by future engine system developments aimed at further
decreasing emissions. This will result in an increase in the fuel
oil lubricity requirement relative to requirements for present
engines. For example, the use of high pressure unit injectors will
likely increase the need for better fuel oil lubricity.
[0005] For the reasons above, there has been an ever-growing effort
to produce additives, which can improve the lubricity of fuels low
in sulfur and/or aromatics. For example, dimer-trimer acids are
sold commercially as lubricity additives. Moreover, commercially
available tall oil fatty acids are used as lubricity improvers for
low sulfur and/or aromatic fuels. A problem associated with
additives based on acids is their tendency to cause gel formation
in the fuel filter, due to an incompatibility with other lube oil
additives into which they may come into contact. For this reason,
some fuel producers specify non-acidic chemistries to avoid these
problems.
[0006] To avoid the problems associated with acid groups, a number
of lubricity improvers are available commercially which have been
produced by reacting the acid to form an amide or ester. For
example, U.S. Pat. Nos. 4,789,493 and 4,808,196 to Horodysky
describe N-alkylalkylenediamine amides and their use as friction
reducing additives in lubricants. As described, these additives are
preferably made by reacting an N-alkylalkylenediamine with a
carboxylic acid. One problem associated with such amide additives
is that the reactions used for their formation can be reversed,
causing a regeneration of the acid which leads to the same
gellation problem in fuel filters encountered as when acidic
lubricity improvers are added. In addition, these additives have a
tendency to cyclize over time.
[0007] U.S. Pat. No. 5,492,641 and EP 0568873 B1 to Mohr disclose
the use of Beta-aminonitriles, and/or N-alkylpropylenediamines
obtained by hydrogenating these Beta-aminonitriles, as detergents
and dispersants in gasoline fuels. It further discloses that these
compounds may be used as lubricant additives for gasoline
fuels.
[0008] U.S. Pat. No. 3,677,726 describes the use of monosubstituted
ureas as varnish-removing fuel additives for hydrocarbon fuel
compositions. It is known that fuel oils are prone to form gum
during periods of prolonged storage that result in formation of
resin-like deposits on equipment, such as fuel lines and filters
that can be problematic. The additives are disclosed as being
effective in removing lacquer and varnish deposits attributable to
gum after they have formed.
[0009] U.S. Pat. No. 3,615,294 to Von Allmen and U.S. Pat. No.
3,762,889 to Newman et al. each describe a gasoline fuel
composition containing a carburetor detergent additive comprised of
the neutral salt reaction product of a substituted urea and a
paraffinic oil oxidate. The substituted urea can be formed from the
reaction between commercial Duomeen (N-alkyldiaminopropane) and
urea. The paraffin oil oxidate, as known in the art, corresponds to
a large and poorly defined group of various types of chemical
functionalities that are formed when oxidizing a base lubricating
oil. This reference does not disclose the use of either the salt
adduct of the substituted urea or the substituted urea itself as
lubricity enhancers, nor does it disclose the use of either of
these compounds in fuels outside those consisting of a mixture of
hydrocarbons in the gasoline boiling range (i.e. from about
75.degree. C. to 450.degree. C.).
[0010] As described above, the poly-aromatic content of a fuel has
dramatic effects on the lubricity of a fuel. Since gasoline and
diesel have very different amounts of aromatic content, it would be
expected that the effects of an additive would behave differently
for each of these fuels. In addition, lubricity is generally not a
problem in a gasoline-based engine because the fuel pump is
lubricated by crankcase oil. In this situation, the lubriciousness
of the fuel is not an issue when considering fuel pump wear. For a
diesel engine, however, the situation is quite different. In these
engines, the lubrication of the fuel pump is accomplished by the
diesel fuel itself.
[0011] There is a growing need in the fuel industry for stable,
non-acidic compounds which can serve as lubricity improvers for
fuels treated to be low in sulfur and/or aromatic components,
particularly given the increasing pressure from regulatory agencies
to produce such fuels worldwide. In particular, there is a need for
lubricity additives for low sulfur diesel fuels.
SUMMARY OF THE INVENTION
[0012] The present invention provides a hydrocarbon fuel oil
composition comprising: (a) a hydrocarbon fuel oil; and (b) one or
more cyclic or open chain urea derivatives formed from an alkylene
polyamine.
[0013] The invention further provides a hydrocarbon fuel oil
composition including a hydrocarbon fuel oil; and a lubricity
additive that includes one or more of the reaction products of (i)
an alkylated polyamine and (ii) urea or isocyanate, or the salt
adducts of these reaction products.
[0014] Also provided is a hydrocarbon fuel oil composition that
includes a hydrocarbon fuel oil having a sulfur content of about
0.01 to about 0.5% by weight per weight of the hydrocarbon fuel;
and a lubricity additive including the reaction products of (i) an
alkylated polyamine and (ii) urea or isocyanate, or the salt
adducts of these reaction products.
[0015] A reaction between (i) an alkylated polyamine and (ii) urea
or isocyanate produces a mixture of reaction products including the
compounds of Formulae I, II, and III, which form the basis of the
lubricity additive compositions of the present invention and the
inventive fuel oil compositions that include them.
[0016] Compounds according to Formulae I, II and III are shown
below. 1
[0017] For each of the formulae above, the substituents are defined
as follows: R.sub.1 is a hydrocarbyl group from C.sub.8-30; R.sub.2
is each independently hydrogen, a hydrocarbyl group from
C.sub.8-30, or the group Y; R.sub.3 is each independently hydrogen,
a hydrocarbyl group from C.sub.8-30, or (CH.sub.2).sub.qOH; R.sub.4
is hydrogen, a hydrocarbyl group from C.sub.8-30,
(CH.sub.2).sub.qOH, or the group Y; R.sub.5 is each independently
hydrogen, a hydrocarbyl group from C.sub.8-30, or
(CH.sub.2).sub.qOH; R.sub.1 is hydrogen, or a hydrocarbyl group
from C.sub.8-30; x is from 2-6 and n is from 1 to 6, or mixtures
thereof; q is from 1 to 6; and Y is as follows, wherein R.sub.3 is
as defined above. 2
[0018] The invention provides an additive composition for
increasing the lubricity of a hydrocarbon fuel oil that includes
one or more cyclic or open chain urea derivatives formed from an
alkylene polyamine.
[0019] Another aspect of the invention relates to an additive
composition for increasing the lubricity of a hydrocarbon fuel oil,
the additive composition including a reaction product of (i) an
alkylated polyamine and (ii) urea or isocyanate, or a salt adduct
of the reaction product, where the reaction product includes a
compound of Formula I.
[0020] A further aspect of the invention is directed to an
inventive lubricity additive composition that includes a mixture of
compounds according to Formula I and Formula II, or the salt
adducts of the mixture.
[0021] Further provided by the invention is a method of making an
additive composition for enhancing the lubricity of a hydrocarbon
fuel oil, the method including reacting (i) an alkylated polyamine
and (ii) urea or isocyanate under conditions to form a compound of
Formula I.
[0022] A further aspect of the invention relates to a process for
improving the lubricity of a hydrocarbon fuel oil, where the
process includes combining the fuel oil with a sufficient amount of
one or more of the reaction products of (i) an alkylated polyamine
and (ii) urea or isocyanate, or the salt adducts of these reaction
products.
DETAILED WRITTEN DESCRIPTION
[0023] It has now been found that certain additive compositions are
capable of improving the lubricity of fuel oils low in inherent
lubricity due to hydrotreating to remove undesirable sulfur and/or
aromatic components. The inventive additive compositions include
one or more cyclic or open chain urea derivatives formed from an
alkylene polyamine. Open chain urea derivatives include compounds
having Formula I or II. Cyclic urea derivatives include the
compounds of Formula III. In one embodiment of the invention, the
alkylene polyamine is N-alkyldiaminopropane. A reaction between (i)
an alkylated polyamine and (ii) urea or isocyanate produces a
mixture of reaction products including the compounds of Formulae I,
II, and III which form the basis for the lubricity additives useful
as components of the hydrocarbon fuel oil compositions of this
invention. The subsequent addition of a low molecular weight
carboxylic acid forms the salt adducts of the mixture, which
provide another basis for useful lubricity additives according to
the present invention.
[0024] For example, one of the products of the reaction between (i)
an alkylated polyamine and (ii) urea or isocyanate is a substituted
urea according to Formula II below. Since the substituted urea is
weakly basic, it can form salts with various acids. In particular,
the substituted urea may undergo an acid-base reaction in the
presence of an acid such as a low molecular weight carboxylic acid
to form a salt. In one embodiment, one or more of the products of
the reaction between (i) an alkylated polyamine and (ii) urea or
isocyanate reacts with propionic acid to form the salt adduct or
adducts.
[0025] In one embodiment, the lubricity additive includes a
compound according to Formula I below, or a salt thereof: 3
[0026] In a further embodiment, the lubricity additive includes the
compound of Formula II below, or a salt thereof: 4
[0027] In yet another embodiment, the lubricity additive includes a
compound of Formula III below, or a salt thereof: 5
[0028] For each of the Formulae above, and throughout the entire
specification, including claims, the substituents are defined as
follows:
[0029] R.sub.1 is a hydrocarbyl group from C.sub.8-30; R.sub.2 is
each independently hydrogen, a hydrocarbyl group from C.sub.8-30,
or the group Y; R.sub.3 is each independently hydrogen, a
hydrocarbyl group from C.sub.8-30, or (CH.sub.2).sub.qOH; R.sub.4
is hydrogen, a hydrocarbyl group from C.sub.8-30,
(CH.sub.2).sub.qOH, or the group Y; R.sub.5 is each independently
hydrogen, a hydrocarbyl group from C.sub.8-30, or
(CH.sub.2).sub.qOH; R.sub.6 is hydrogen, or a hydrocarbyl group
from C.sub.8-30; x is from 2-6 and n is from 1 to 6, or mixtures
thereof; q is from 1 to 6; and Y is as follows, wherein R.sub.3 is
as defined above. 6
[0030] In one embodiment of this invention, the lubricity additive
includes a mixture of the compounds of Formulae I, II, and III or
salt adducts of the mixture. In one desired embodiment, the ratio
of the compound of Formula I to the compound of Formula II in this
mixture is about 1:1 to about 4:1. In another preferred embodiment,
the ratio of the compound of Formula I to the compound of Formula
II in the mixture is about 1.5:1 to about 2.5:1. In a further
embodiment, the preferred ratio of the compound of Formula III to
the combined mixture of compounds of Formula I and II is about 0:1
to about 2.5:1.
[0031] The lubricity additive of the invention preferably includes
a predominant amount of a mixture of the compounds of Formulae I
and II, or salt adducts of the mixture. For purposes of the present
invention, by the term predominant it is meant that the mixture of
compounds is present in greater amounts relative to other
components which may be present. It is noted that one or another of
the products of the reaction between (i) an alkylated polyamine and
(ii) urea or isocyanate, or their salt adducts, may be enriched
relative to the other reaction products.
[0032] As indicated above, the lubricity additives useful for this
invention find particular application in low sulfur fuel oils. The
fuel oil preferably has a sulfur concentration of 0.2 percent by
weight or less based on the weight of the fuel, and desirably 0.05
percent or less. Such fuels may be made by methods known in the
fuel-producing art including solvent extraction,
hydrodesulfurization and sulfuric acid treatment. While these fuels
may be hydrocarbon fuels, oxygenates or mixtures of hydrocarbon
fuels and oxygenates may also be useful for this invention. The
hydrocarbon fractions which may be used for the fuel compositions
include distillate fuels which boil in the kerosene and gas oil
range (165.degree. C. to 560.degree. C.). Typical middle distillate
fuels of this type would include road diesel and other diesel fuels
which have boiling ranges of about 200-307.degree. C., as well as
jet fuels, kerosenes, gas oil and cycle oils. These middle
distillate fuels can include straight run distillate oils,
catalytically or thermally cracked distillate fuel oils, as well as
mixtures of straight run distillate fuel oils with cracked
distillate stocks. Normally, these fuels are derived from
petroleum, however they may also be derived, at least in part, from
other sources including shale, tar sands, coal, lignite, biomass
and similar sources. Moreover, the fuels may include oxygenate
blending components such as alcohols or ethers. It is within the
contemplation of the present invention that the fuels may also
wholly comprise oxygenates such as ethanol and/or methanol.
Furthermore, the fuels of the compositions of the present invention
may also be those which have been subjected to conventional
treatment processes including treatment with acid or base,
hydrogenation, solvent refining or clay treatment.
[0033] While the fuel compositions of the present invention may be
used in jet engines, gas turbines, or diesel engines, in a desired
embodiment of the invention the fuel is one which is suitable for
use in a diesel engine. Diesel fuels can vary widely in composition
depending on the nature of the crude oil, the refining process, the
components with which the raw fuel is blended, as well as other
factors. The use of this invention as noted above finds a
particularly desired application in diesel fuels which have a
reduced sulfur and/or aromatic content which are now being produced
worldwide in order to comply with the requirements of regulatory
agencies. While normal diesel fuel, with sulfur content typically
greater than 500 ppm, offers some protection against metal wear,
the low sulfur hydrotreated fuels now coming on the market with
sulfur contents typically below 500 ppm and/or an aromatic content
of less than 35 percent by weight, do not afford the same natural
anti-wear lubricity protection. In general, however, the fuel and
its inherent lubricity is expected to vary according to the
severity of the regulatory requirements. For example, many low
sulfur fuels have sulfur content less than 50 ppm and would be
expected to have an inherent lubricity much less than that of a
fuel having a sulfur content of 500 ppm.
[0034] As a result of the variance in inherent lubricities between
fuels, the amount of the lubricity additive sufficient to improve
the lubricity of the fuel compositions of this invention may vary
from about 5 to about 5000 ppm by weight per weight of the fuel.
Desirably, the concentration of the additive is about 50 to about
300 ppm by weight per weight of the fuel.
[0035] The present invention may also find application in the area
of aviation fuels, such as those conventionally used in jet turbine
engines. These fuels have a composition which is quite close to
that of diesel fuels having low aromatic and low sulfur content. It
is well within the contemplation of the present invention that the
addition of the lubricity additives to the fuel compositions of
this invention can improve lubricity and reduce engine wear with
concentrations of the additive in the range of about 5 to about
5000 ppm by weight per weight of the fuel.
[0036] Regardless of the fuel used in this invention, the key
aspect is the desire to improve the lubricity of the fuel.
Therefore, fuels having some lubricity can be used as components of
the fuel compositions of this invention, however, it is the fuels
which have minimal lubricity or at the minimum accepted lubricity
values or less that are desired for use in this invention.
[0037] The fuel compositions according to this invention may also
include numerous other additives. Among these are flow improvers,
waxy anti-settling additives, demulsifying agents, cloud point
depressants, anti-static additives, anti-oxidants, biocides, odor
masks, metal deactivators, anti-foams, detergents/dispersant
additives, dyes, cetane improvers, as well as other lubricity
additives.
[0038] The fuel oil compositions of the present invention may be
produced by incorporation of either the additive alone or an
additive composition wherein the additive composition may include
other additive compounds including demulsifying agents, corrosion
inhibitors, anti-oxidants, dyes, and the like, provided that they
do not adversely affect the anti-wear effectiveness of the amino
functional fatty acid oligomers used as lubricity additives for the
fuel compositions of this invention and that the components of such
mixtures are compatible.
[0039] Moreover, the additive or additive composition may be
present as a liquid concentrate. The amount used of each of these
compositions will be such as to insure the incorporation into the
fuel of the requisite amount of the lubricity additive. For
example, regardless of whether the additive is present in a
concentrate composition, the amount of the active ingredient of the
additive will be in the range of about 5 to about 5,000 ppm by
weight per weight of the base fuel.
[0040] The present invention provides for a method of making an
additive composition for enhancing the lubricity of a hydrocarbon
fuel oil, where the method includes reacting (i) an alkylated
polyamine and (ii) urea or isocyanate under conditions to form a
compound of Formula I. In a further embodiment, the method includes
reacting (i) an alkylated polyamine and (ii) urea or isocyanate
under conditions to form a mixture of the compounds Formula I and
Formula II. In yet another embodiment, (i) an alkylated polyamine
and (ii) urea or isocyanate are reacted under conditions to form a
mixture of the compounds of Formulae I, II, and III.
[0041] The present invention also provides for a process for
improving the lubricity of a hydrocarbon fuel. This process
includes the step of combining with the fuel a sufficient amount of
one or more of the reaction products of (i) an alkylated polyamine
and (ii) urea or isocyanate, or the salt adducts of these reaction
products to improve the lubricity of the fuel. The lubricity
additive may be combined in an amount of about 5 to about 5000 ppm,
and desirably combined in an amount of about 50 to about 300
ppm.
[0042] Conventional blending equipment and techniques may be used
in preparing the fuel compositions of the present invention.
Blending is normally carried out at ambient temperature.
[0043] The present invention further provides for an internal
combustion engine system wherein the engine system includes fuel
oil compositions herein described which have improved lubricity due
to the presence of one or more of the reaction products of (i) an
alkylated polyamine and (ii) urea or isocyanate, or the salt
adducts of these reaction products.
[0044] As will become readily apparent by the following examples,
lubricity evaluation tests reveal that the inventive fuel
compositions containing one or more of the reaction products of (i)
an alkylated polyamine and (ii) urea or isocyanate, or the salt
adducts of these reaction products out-perform fuel compositions
containing many of the prior art lubricity additives in terms of
improving the lubricity and reducing and/or inhibiting the amount
of engine system wear.
EXAMPLES
Example 1
[0045] This example demonstrates that the present fuel compositions
show superior lubricity properties to fuel compositions treated
with prior art additive compounds conventionally used for improving
lubricity in fuels.
[0046] The results of the present example indicate that both the
additive composition that includes the reaction products of
N-alkyldiaminopropane and urea (Inventive Composition 1) and the
inventive additive composition including the salt adducts of these
reaction products (Inventive Composition 2) improve the lubricity
of a low sulfur diesel fuel when using the low frequency
reciprocating rig (LFRR) test as the evaluator test for lubricity.
The LFRR test is based on a modified version of ASTM D-6079. In
this method, a test specimen of fuel is placed in a reservoir and
adjusted to a temperature of approximately 65.degree. C. A vibrator
arm holding a non-rotating steel ball and loaded with a 200 g mass
is lowered until it contacts a test disk completely submerged in
the fuel. The ball is caused to rub against the disk with a 2 mm
stroke at 20 Hz for 75 minutes. The amount of wear is then measured
under magnification over a distance of millimeters by measuring the
flat spot and grooved surface which typically is present on the
ball due to wear. It is generally accepted that diesel fuels with
LFRR test values of 460 .mu.m or less have good lubricity, while
those with values exceeding 610 .mu.m have poor lubricity. A dose
response with the inventive lubricity additive compositions was
compared to two commercial benchmark materials (Compound A and
Compound B). The dose response was conducted by an outside facility
using LFRR in a sample of Canadian low sulfur diesel fuel, with the
following results reported as Wear Scar Diameters (WSD) in Table 1
below, wherein a lower Wear Scar Diameter indicates greater
efficacy. The base fuel had less than 0.05 weight percent sulfur
and less than 37 weight percent in aromatics, with a kinematic
viscosity at 100.degree. F. of 2.1 centistokes.
1TABLE 1 25 37.5 40 60 Additive ppm ppm ppm 45 ppm 50 ppm 55 ppm
ppm Compound B 600 586 Compound A 736 381 419 Inventive 708 642 664
638 468 417 Composition 1 Inventive 714 669 370 389 Composition
2
[0047] In Table 1, the doses in ppm for all compounds are reported
as ppm by weight of the active ingredient per weight of the fuel.
The results presented in Table 1 show that when Inventive Additive
Composition 1 is added to the base fuel at 55 ppm and 60 ppm to
produce an inventive fuel oil composition, the LFRR values are 468
and 417 .mu.m, respectively, which are at or lower than the 460
.mu.m conventionally accepted value for a diesel fuel having good
lubricity characteristics. Furthermore, at 60 ppm of Inventive
Composition 1, the lubricity of the base fuel is superior to a fuel
composition containing 60 ppm of prior art Compound B.
[0048] The results in Table 1 also indicate that the lubricity of
the base fuel can be further enhanced when the salt adducts of the
reaction products of N-alkyldiaminopropane and urea are used
(Inventive Composition 2). For example, the LFRR values obtained
with 45 ppm and 50 ppm of the salt adduct were even lower than
those obtained with higher amounts (i.e., 50-60 ppm by weight) of
Inventive Composition 1. In addition, at 50 ppm Inventive Additive
Composition 2 enhances the lubricity of the base fuel to a greater
extent than 50 ppm of prior art Compounds B and A, which yielded
LFRR values of 600 and 419 um, respectively.
Example 2
[0049] The present example demonstrates that the inventive additive
compositions improve the lubricity of low sulfur hydrocarbon fuel
oils. The example further demonstrates that particular ratios of
compounds of Formulae I, II, and III improve the lubricity to a
greater extent than other ratios, or the Duomeen-T starting
material.
[0050] The reaction useful for preparing the additive compositions
of the present invention proceeds from the starting materials,
N-alkyldiaminopropane (Duomeen-T) and urea, through a set of
intermediates corresponding to the compounds of Formulae I and II
to the compound of Formula III as shown in Scheme 1 below:
Starting Materials.fwdarw.Compounds I and II.fwdarw.Compound
III
[0051] The identities of each of the reaction products of Scheme 1
were determined by NMR spectroscopy on a 300 MHz Varian Unity Plus
Spectrophotometer. Compound III in Scheme 1 is the
thermodynamically favored product at high temperatures, whereas the
intermediate Compounds I and II can be kinetically frozen by
lowering the temperature before the reaction is complete. Given
this situation, it was possible to take samples from the reaction
at different time points to obtain compositions having various
ratios of the starting materials and compounds in Scheme 1. In
particular, within the two hours it took to complete the reaction
of scheme 1, samples were removed at four different time points.
These samples, referred to as S1, S2, S3 and S4, contained
different relative amounts of the starting materials and compounds
according to Formulae I, II and III as indicated below.
[0052] S1 approximately: 44% starting material, 37% Compound I, 19%
Compound II, 0% Compound III.
[0053] S2 approximately: 0% starting material, 42.5% Compound I,
19.5% Compound II, 38% Compound III.
[0054] S3 approximately: 0% starting material, 20% Compound I, 8%
Compound II, 72% Compound III.
[0055] S4 nearly pure amount of Compound III.
[0056] Each of these fractions S1-S4 were tested for their ability
to improve the lubricity of a low sulfur diesel fuel by using the
low frequency reciprocating rig (LFRR) test described in Example 1
above as the evaluator test for lubricity. In particular, each of
these samples was evaluated at 100 ppm by weight of the active
ingredient (S) per weight of the fuel. As described above, a lower
Ware Scar Diameter (WSD) indicates greater efficacy.
2 TABLE 2 Sample WSD Blank 668 Duomeen-T 398 S1 413 S2 302 S3 357
S4 584
[0057] As indicated by the results in Table 2, each of samples
S1-S4 improve the lubricity of the base fuel. Sample S2, which has
the highest ratio of Compounds I and II to Compound III, but no
starting material, has the greatest efficacy. Table 2 further
indicates that the starting material Duomeen-T also provides
lubricity protection. However, the efficacy of samples S2 and S3 is
greater than that of Duomeen-T at 100 ppm. Whereas Table 2 does
indicate that sample S4 improves the lubricity of the base fuel,
the efficacy is less than that obtained with samples S1-S3 or the
Duomeen-T starting material. However, there does appear to be an
increase in the lubricity of the base fuel when fraction S4 is
mixed with sample S2. This data is shown in Table 3 below, which
shows the LFRR values reported as wear scar diameters obtained from
mixing the samples S 1-S4, in various ratios, with one another or
the Duomeen-T (D-T) starting material. In particular, since sample
S2 works more effectively by itself than does sample S4 by itself,
this would imply that sample S4 is exhibiting synergy at both 25
and 50 weight percent levels. With further reference to Table 3
below, it is noted that the opposite occurs when Duomeen-T is added
to S2 in the same proportions.
3TABLE 3 S2 (ppm) S4 (ppm) WSD S2 (ppm) D-T (ppm) WSD 100 0 302 100
0 302 75 25 280 75 25 338 50 50 289 50 50 404 25 75 338 25 75 398 0
100 584 0 100 398 S4 (ppm) D-T (ppm) WSD S3 (ppm) D-T (ppm) WSD 100
0 584 100 0 357 75 25 423 75 25 397 50 50 389 50 50 314 25 75 -- 25
75 381 0 100 398 0 100 398
[0058] The results in Tables 2 and 3 further indicate that while
the preferred additive composition has little or no starting
material, it can be seen that the starting material Duomeen-T can
improve the lubricity of a base HC fuel, either alone or in
combination with samples S3 or S4, which each contain high amounts
of the cyclic urea derivative having Formula III. For example,
referring to Table 3, the results show that mixing sample S3 or
sample S4 with Duomeen-T leads to an increase in lubricity at 50
weight percent levels.
[0059] In conclusion, the present example demonstrates that the
addition of S4 at 25-50 weight percent levels enhances the efficacy
of sample S2. This implies that the Compound of Formula III (a
cyclic urea derivative) synergizes with the components of sample S2
to improve the overall lubricity of the base fuel relative to
sample S2 alone. We can further conclude from this example that for
those samples having higher concentrations of Compound III (S3 and
S4), addition of the starting material Duomeen-T at 50% weight
percent levels improves the lubricity of the base fuel relative to
either sample S3 or S4 alone. Moreover, the addition of Duomeen-T
at any weight percent level does not appear to improve the
lubricity of sample S2, which has a higher ratio of (Compounds I
and II) to Compound III than does S3 or S4.
[0060] Finally, we conclude that particular ratios of compounds
according to Formulae I, II, and II provide greater efficacy than
other ratios of these compounds, or the starting material. The
sample including the highest ratio of (Compounds I and II) to
Compound II, but no starting material (sample S2), provides a
preferred embodiment of the additive composition of the present
invention.
* * * * *