Note: Descriptions are shown in the official language in which they were submitted.
(.:
WO h1/1Z303 PC.'T/US91/0093A
O1 FUEL ADDITIVE COMPOSITION
02
03 BACKGROUND OF THE INVENTION
04
05 Numerous deposit-forming substances are inherent in ,
06 hydrocarbon fuels. These substances when used in internal
07 combustion engines tend to form deposits on and around
08 constricted areas of the engine contacted by the fuel.
09 Typical areas commonly and sometimes seriously burdened by
the.formation of deposits include carburetor air bleeds; the
11 throttle body and venturies, engine intake valves and
12 ports, fuel injection nozzles, cylinder head and piston top
13 combustion chamber surfaces, etc.
14
Deposits adversely affect the operation of vehicles using
16 hydrocarbon fuels. For example, deposits on the carburetor
17 throttle body and venturies increase the fuel-to-air ratio
18 of the gas mixture to the combustion chamber thereby '
19 increasing the amount of unburned hydrocarbon and carbon
monoxide discharged from the chamber. High Euel-to-air
21 ratios also reduce the gas mileage obtainable from the
22 vehicle.
23
Deposits on the engine intake valves that are sufficiently
heavy, restrict the gas mixture flow into the combustion
26 chamber. This restriction starves the engine of air and
27 fuel and results in a loss of power. Deposits on the valves
28 also increase the probability of valve failure due to
2g burning and improper valve seating. In addition, these
deposits may break off and enter the combustion chamber
31 possibly resulting in mechanical damage to the piston top,
32 piston rings, cylinder head, etc.,
33
34
WO g1/12303 PCT/U591/009~:~.f
O1 It has long~been known that the formation of these deposits
02 can be inhibited as well as removed by incorporating an
03 active detergent into the fuel. These detergents function
04 to cleanse these deposit-prone areas of the harmful
05 deposits, thereby enhancing engine performance and
06 longevity.
07
08 The first generation of fuel additives consisted of
09 detergents which helped to maintain the cleanliness of
critical carburetor elements. These initial fuel additives
11 were typically used in small doses, generally in the range
12 of 15 to 30 ppm. Unfortunately, these small doses of
13 additive provided little deposit control in other parts of
14 combustion engines.
16 The next generation of fuel additives generally provided
17 improved deposit control in the intake system including
18 intake manifold hotspots, runners, intake valve ports, and
19 intake valves. The extent of deposit control was typically
modulated by controlling additive dose, usually in the range
21 of 70 to 2,000 ppm. However, as additive doses increased to
22 high levels, the accumulation of combustion chamber deposits
23 became a significant problem for reasons which will become
24 apparent hereinbelow.
26 zn recant years the wide-spsead use of non-leaded gasoline
27 has further complicated the use of detergent-type gasoline
2g additives. In automobile engines that require the use of
2g non-leaded gasolines (to~prevent disablement of catalytic
converters used to reduce emissions?. it has been found
31 difficult to provide gasoline of sufficient octane to pre-
32 vent knocking and the concomitant damage which it causes.
33 The problem arises from an octane requirement increase,
34
WO 91/12303 PCT/US91/00934
3
O1 herein called "ORI", which results from deposits formed by .
02 the use of commercial gasolines.
03
04 The basis of the ORI problem is as follows: each engine,
05 when new, requires a certain minimum octane fuel in order to
06 operate satisfactorily without pinging and/or knocking,
07 and/or after run. As the engine is operated an any
Og gasoline, this minimum octane requirement increases. This
Og is apparently caused by formation of deposits in the com-
bustion chamber. In mast cases, if the engine is operated
11 on the same fuel for a prolonged period, the ORI will reach
12 an equilibrium. Equilibrium is typically reached after
13 5,000 to 15,000 miles of automobile operation.
14
The octane requirement increase in a particular engine used
16 with commercial gasolines will vary at equilibrium from 4 to
1' 6 octane units to as high as 12 or l5 units, depending upon
1g the gasoline compositions, engine design and type of oper-
lg ation. The seriousness of the problem is thus apparent. A
typical automobile with a research octane requirement of 85,
21 when new, may after a few months of operation require 97
22 research octane gasoline for proper operation, and little
23 unleaded gasoline of that octane is available. The ORI
24 problem also exists to some degree with engines operated on
Z5 leaded fuels. U.5. Patent Nos. 3,144,311; 3,146,203; and
26 4,247,301 disclose lead-containing fuel compositions having
2~ reduced ORI properties.
28
2g The ORI problem is compounded by the fact that the most
common method for increasing the octane rating of unleaded
31 gasoline is to increase its aromatic content. These aroma-
32 tics, however, eventually cause an even greater increase in
33 the octane requirement. Moreover, some of the nitiogen-
34 containing compounds presently used as deposit-control
~0~~'~a~
Z..
WO 91IIZ303 PCT/US911009~a
H
O1 additives~and their mineral oil or polymer carriers may also
02 significantly contribute to ORI in engines using unleaded
03 fuels.
04
05 It is, therefore, particularly desirable to provide degosit
06 control additives at doses sufficient to effectively control
07 the deposits in .intake systems of engines without themselves
08 significantly contributing to the ORI problem.
0g
I0 In this regard, the hydrocarbyl poly(oxyalkylene)
11 aminoca.rbamate dispersants are commercially successful fuel
12 additives which control induction system deposits without
13 significantly contributing to the ORI problem. However,
I4 these additives are relatively expensive and this
15 discourages their use in high concentrations.
16
,17 At economical fuel concentrations, the hydrocarbyl
18 poly(oxyalkylene) aminocarbamates are not quite as effective
19 at controlling deposits in the injectors or carburetor of
ZO mode'rn combustion engines. The performance of these
Z1 engines, Which contain fuel injection fuel delivery systems,
22 can be substantially upset by relatively small amounts of
23 deposits.
24
25 On the other hand, low molecular weight hydrocarbyl amine
2~ and polyamine detergents are known to effectively control
27 deposits in injectors. These amine detergents are similar
2g to those described easlier that were used to maintain clean
2g carburetors. However, to control deposits on injectors,
3p these detergents are used at fuel concentrations in the
31 range of 40 to 70 ppm. It is now known that such high doses
32 of injector detergents negatively impact the control of
33 deposits on intake valves and in the combustion chamber of
34 engines.
~U~3~JJ a.,
W~ 91/12303 ~ PLTJUS91/00934
O1 An additional problem with some low molecular weight
02 hydrocarbyl amine and polyamine detergents that contain a
03 primary or secondary amine functionality is the formation of
04 a solid precipitate when the amine is exposed to carbon
05 dioxide, such as exposure to the carbon dioxide in air. It
06 is believed that this precipitate is a carbamic acid adduct
07 formed by reaction of the primary or secondary amine with
08 carbon dioxide. whatever its chemical structure, formation
09 of such a precipitate is undesirable for reasons which will
be explained hereinbelow.
1I
I2 A further problem associated with some low molecular weight
13 amines; particularly those containing polar substituents
14 such a.s hydroxy groups, is the fact that these amines have a
1S high water solubility, and therefore, on contact with water,
16 can be completely extracted out of the hydrocarbon phase and
17 into the water phase. As a result, such amines would have
I8 reduced effectiveness in hydrocarbon fuels.
19
In this regard, U.S. Patent No. 4,810.263 to Zimmerman et
21 al. discloses an additive package for reducing and/or
22 preventing fouling in a multiport fuel-infected engine which
23 contains an amine oxide, such as bis(2-hydroxy ethyl)
24 cocamine oxide, and a demulsifier comprising one or more
demulsifying agents selected from a fatty acid alkylamine
26 reaction product and a solution of oxyalkylated alkylphenol
27 formaldehyde resins and polyglycols. U.S. Patent
28 No. 4,836,829 to Zimmerman et al discloses a similar addi-
2g tive package which contains a tertiary amine, such as
bis(2-hydroxy ethyl) cocamine, preferably in combination
31 with an amine oxide. and a demulsifying agent. As noted in
32 U.S. Patent No. 4,810,263, the amine oxide typically has
33 water present from the manufacturing process, which is
34 difficult to comgletely remove. As a result, the amine
VfO 91/12303 ~ PGT/US91/OOgs4
O1 oxide is commercially available as an isopropyl'alcohol
02 solution which contains from 6 to 8 weight percent water.
03
04 Frequently, mineral oil carriers are used with either the
OS amine detergents or the hydrocarbyl poly(oxyalkylene)
06 aminocarbamate dispersants to assist in rsemaving and
07 preventing deposits. However, even with t:he addition of
0$ mineral oil carriers, neither group of fuel additives
09 provides complete intake system deposit control.-
1I It would, therefore, be particularly desirable to combine an
12 intake valve and combustion chamber degosit control addi-
13 tive, such as a hydrocarbyl poly(oxyalkylene) aminocarbamate
14 dispersant, with an injector detergent, such as a low
I5 molecular weight amine or polyamine, and an effective amount
I6 of a carrier fluid to provide a multi-component, multi-
17 functional fuel additive package which maximizes effective
1g control of deposits throughout the entire intake system and
19 combustion chamber of engines, and which itself does not
significantly contribute to the octane requirement increase
21 problem.
22
23 The choice of components for a mufti-component,
24 mufti-functional deposit control fuel additive composition
is not straightforward. The composition must provide
26 effective deposit control at additive levels which are
2~ economical, and with additives which do not contribute to
28 ORI. It is also essential that the composition remains
29 homogeneous, i.e., a single liquid phase, under all field
conditions, if the composition is to dependably deliver the
31 expected deposit control performance when blended with fuel
32 and in actual engine service.
33
34
~t
VVO 91/1Z303 IP~CT/US91/~0934
7
O1 In providing an effective fuel additive composition,
02 maintaining a single liquid phase is critical. Typically,
03 there are no practical means to re-homogenize an additive
04 composition once distributed to the field. If the bulk ,
05 additive composition separates into two or more phases, as a
06 result of component incompatibility, neither phase will
07 contain the effective combination of components intended for
08 the fuel. Therefore, the overall deposit control per-
09 formance of the fuel will be seriously degraded.
Furthermore, the composition of additive delivered to the
12 fuel will be erratic.
12
I3 The phase separation of an incompatible composition can take
14 many forms. Typically, the phase separation appears first
as a haze Which eventually settles out, either up or down,
I6 depending on the relative densities of the two phases. Thus
17 as the level of additive in, for example, a storage tank is
1g drawn down, the interface between the phases may pass below
1g the liquid draw point, at which time the composition of
ZO additive flowing into the fuel will change, perhaps
Zl drastically.
Z2
23 A phase separation will also cause serious problems in the
24 additive distribution system which distributes the additive
ZS composition to the fuel. If the phase separation involves
26 two liquid phases, the heavier phase will collect on the
27 bottom of the additive storage tank and at the low points of
Zg the additive delivery lines. This will result in the need
29 for expensive and inconvenient periodic cleanout of the
30 additive distribution equipment.
31
32 If the phase separation involves a solid separating from the
33 bulk liquid additive composition, the effect would be more
34 serious and immediate. Virtually all additive injection
~~~~~5~ ~_
VbrO 91/12303 PCTlUS9IlfHD~:..:e
O1 systems have fine-mesh filters to pcotect the valves and
02 seals in the injection Bump. A solid phase would rapidly
03. plug these filters and shut down the injector, thus
04 requiring that the filter be cleaned before restarting the
05 injector. A separate solid phase would also require the
06 periodic cleaning of the additive storage tank. The
0? criticality of a homogeneous additive composition is thus
08 apparent.
09
IO It is generally considered beneficial to include a minor
I1 amount of a material which has fuel/water demulsifirr
I2 properties in fuel blends of additive compositions. The
13 demulsifier must exhibit demulsification properties when
14 utilized in motor fuels at relatively low levels, such -as 5
15 to 25 parts per million. However, it has been observed that
16 even low dosages of such material can, in certain instances,
I? have a negative effect on the deposit-inhibiting properties
18 of the additive composition. Consequently, it is desirable
1g to choose a demulsifier which does not exhibit this negative
20 effect. In addition, it is critical that the demulsifier
21 remain homogeneous with the additive composition for reasons
22 cited hereinabove.
23
24 It is also generally beneficial to include a solvent or
25 diluent in the additive composition. The primary function
26 of this component' is to reduce the low-temperature viscosity
2? of the composition. The solvent must however be compatible
28 with the additive components and economical.
29
30 Relevant Art
31
32 ~.8. Patent Nos. 4,160,648 and 4,191,537 disclose
33 hydrocarbyl poly(oxyalkylene) aminocarbamates as fuel
34 additives. The use of a fuel-soluble carrier oil and,
WQ ~1/I2303 Pt.T/US91100934
O1 additionally, a demulsifier in combination with the
02 hydrocarbyl poly(oxyalkylene) aminocarbamates is also
03 disclosed.
04
05 The use of hydrocarbyl amines and hydrocarbyl polyamines as
06 fuel additives is disclosed in U.S. Patent Nos.:
07
O8 3,438,757; 3,898,056; and
Og 3,565,804; 3,960,515
3,574,576
1I
12 U.S. Patent Nos. 3,898,056 and 3,960,515 disclose a mixture
13 of high and low molecular weight hydrocarbyl amines used as
14 detergents and dispersants at low concentrations in fuels.
The high molecular weight hydrocarbyl amine contains at
16 least one hydrocaryl group having a molecular weight from
17 about 1,900 to 5,000 and the low molecular weight hydro-
18 carbyl amine contains at least one hydrocarbyl,group having
1g a molecular weight from about 300 to 600. The weight ratio
of low molecular weight amine to high molecular weight amine
21 in the mixture is maintained between about 0.5:1 and 5:1.
2Z
23 while these references disclose hydrocarbyl poly(oxyalkylene)
24 aminocarbamates useful as dispersants and hydrocarbyl amines
and polyamines useful as detergents, none of these references
26 teach a homogeneous additive composition comprising a dis-
27 persant, detergent, carrier oil and demulsifier which, when
2g mixed with fuel at low concentrations, provides effective
2g deposit control throughout the entire intake system while
minimizing contribution to the olti problem.
31
32
33
34
i~VO 9i/12303
P~If'/LJS9I lOOys4
ID
01 SUD1MARY OF THE INVENTION
02
03 The present invention provides a novel homogeneous fuel
04 additive composition which comprises:
OS
06 (a) a dispersant comprising a hydrocarbyl poly(oxyalkylene)
07 aminocarbamate having at least one basic nitrogen atom
08 and an average molecular weight of about 1,000 to about
09 3,000;
IO
11 (b) an injector detergent comprising a branched-chain
12 hydrocarbyl amine having at least one basic nitrogen
13 atom and an average molecular weight of about 300 to
,14 about 700, wherein the hydrocarbyl moiety is derived
15 ~rom polymers of C2 to C6 olefins;
16
I? (c) a fuel demulsifier which is homogeneous with the other
18 components of said fuel additive composition) and
19
20 (d? a natural or synthetic carrier fluid.
21
22 The present invention further provides a fuel composition
23 comprising a hydrocarbon boiling in the gasoline or diesel
24 range and from about 400 to 1,200 parts per million of the
2$ homogeneous fuel additive composition described above.
26
27 The present invention is also concerned With a fuel
28 concentrate comprising an inert stable oleophilic organic
29 solvent boiling in the range of 150° to 400°F and from about
30 S to 50 weight percent o~ the homogeneous fuel additive
3I composition of the invention.
32
33 Among other factors, the present~invention is based on the
34 surprising discovery that the unique combination of
~~4~~~~
..
WO gl/1Z303 PGTIUS91/00934
9l
O1 dispersan~, low molecular weight injector detergent,
02 demulsifier and carrier fluid described herein provides com-
03 plate intake deposit control while minimizing debilitating
04 combustion chamber deposits, which correlate to ORI.
05
06 In addition, the use of a low molecular weight branched
07 chain hydrocarbyl amine as an injector detergent avoids the
08 precipitation problem associated with known amine deter-
Og gents, such as oleyl amine.
I0
11 DETAILED DESCRIPTION OF THE INVENTIaN
I2
13 In essence, the present invention addresses the problem
14 associated with the fact that none of the prior art fuel
ZS additives can singly, or in typical use concentration com-
I6 binations, grovide complete gasoline intake system deposit
I7 control. The instant invention demonstrates a new formulat-
18 ing technology which provides maximum deposit control in
Ig each critical deposit forming area while at the same time
ZO minimizing the doses of each critical ingredient. As a
21 consequence, it is now possible to minimize the negative
ZZ impact of each individual ingredient upon overall intake
Z3 system and combustion chamber deposit control performance.
2'4
Z5 The instant invention describes a fuel additive composition
26 which provides a homogeneous mixture of deposit control
.Z7 additives and carrier fluid, in individual proportions
Z8 significantly below tha levels historically recognized for
Zg maintaining adequate intake system deposit control in their
30 respective areas of effectiveness, and an oil compatible
31 demulsifier.
32 _
33
34
._.
WO 91112303 FCT/US9~t00~5~a4
/~
O1 Accordingly, the novel fuel additive composition of the
02 present invention is a homogeneous mixture which comprises
A3 the following components:
04
05 (a) a dispersant comprising a hydrocarbyl poly(oxyalkylene)
OS aminocarbamate having at Least one basic nitrogen atom
07 and an average molecular weight of about 1.000 to about
08 3,000,
09
(b) an injector detergent comprising a branched-chain
1I hydrocarbyl amine having at least one basic nitrogen
12 atom and an average molecular weight of about 300 to
13 about 700, wherein the hydrocarbyl moiety is derived
14 from polymers of C2 to C6 olefins;
16 (c) a fuel demulsifier which is homogeneous with the other
17 components of said fuel additive composition) and
18
19 (d) a natural or synthetic carrier fluid.
21 In general, the homogeneous fuel additive composition of the
22 invention will contain about 10 to 70 weight percent of the
Z3 aminocarbamate dispersant, about 1 to 10 weight percent of
24 the hydrocarbyl amine injector detergent, about 0.5 to
Z5 5 weight percent of the fuel demulsifier and about 25 to
26 80 weight percent of the carrier fluid. Although the
27 present fuel additive composition can be used neat, it is
28 often desirable to dilute the composition with a.n inert
29 solvent or diluent, up to about 50 percent dilution.
3I The Dispersant
32
33 The dispersant employed in the homogeneous fuel additive
34 composition of the invention is a hydrocarbyl
fy0 91!12303 PCTlUS91l00934
~3
Ol poly(oxyalkylene) aminocarbamate having at least one basic
02 nitrogen atom and an average molecular weight o~f about 1,000
03 to 3,000. Thus the dispersant employed can be said to
04 contain a poly(oxyalkylene) component, an amine component
05 and a carbamate connecting group.
06
0? A. The Poly(oxyalkylene.) Component
08
09 The hydrocarbyl-terminated poly(oxyalk~Ylene) polymers
IO which are utilized in preparing the carbamates of the
11 present invention are monohydroxy compounds, e.g.,
12 alcohols, often termed monohydroxy polyethers, or
13 polyalkylene glycol monocarbyl ethers, or "capped"
14 poly(oxyalkyle,ne> glycols, and are to be distinguished
15 from the goly(oxyalkylene) glycols (diols), or polyols,
16 which are not hydrocarbyl-terminated, i.e., are not
1? capped. The hydrocarbyl-terminated poly(oxyalkylene)
18 alcohols are produced by the addition of lower alkylene
!g oxides, such as oxirane, ethylene oxide, propylene
20 oxide, butylene oxide, etc. to the hydroxy compound,
21 RAH, under polymerizatian conditions, wherein R is the
22 hydrocarbyl group which caps the poly(oxyalkylene)
23 chain. In the poly(oxyalkylene) component employed in
24 the present invention, the group R will generally
25 contain from 1 to about 30 carbon atoms, preferably from
26 2 to about 20 carbon atoms and is preferably aliphatic
2? or aromatic, i.e., an alkyl or alkyl phenyl wherein the
28 alkyl is a straight or branched-chain of from 1 to about
2g 24 carban atoms. More preferably, R is alkylphenyl
30 wherein the alkyl group is a branched-chain of 12 carbon
31 atoms, derived from propylene tetramer, and commonly
32 referred to as tetrapropenyl._ The oxyalkylene units in
33 the poly(oxyalkylene) component preferably contain from
34 2 to about 5 carbon atoms but one or more units of a
i ;.
CA 02049954 2002-05-16
' 14
O1 larger carbon number may also be present. The
02 poly(oxyalkylene) component employed in the present
03 invention is more fully described and exemplified in
04 U.S. Patent No. 4,191,537.
05
06 Although the hydrocarbyl group on the hydrocarbyl
07 poly(oxyalkylene) component will preferably contain from
08 l to about 30 carbon atoms, longer hydrocarbyl groups,
09 particularly longer chain alkyl phenyl groups, may also
be employed.
11
12 For example, alkylphenyl poly(oxyalkylene)
13 aminocarbamates wherein the alkyl group contains at
14 least 40 carbon atoms, as described in U.S. Patent
No. 4,881.945 to Buckley, are also contemplated for use
16 in the present invention. The alkyl phenyl group on the
17 aminocarbamates of U.S. Patent No. 4,881,945 will pre-
18 ferably contain an alkyl group of 50 to 200 carbon
1g atoms, and more preferably, an alkyl group of 60 to 100
carbon atoms.
21
22 B. The Amine Component
23
24 The amine moiety of the hydrocarbyl-terminated
poly(oxyalkylene) ami.nocarbamate is preferably derived
26 from a polyamine having from 2 to about 12 amine
27 nitrogen atoms and from 2 to about 40 carbon atoms. The
28 polyamine is preferably reacted with a hydrocarbyl poly-
29 (oxyalkylene) chloroformate to produce the hydrocarbyl
poly(oxyalkylene) aminocarbamate fuel additive finding
31 use within the scope of the present invention. The
32 chloroformate is itself derived from hydrocarbyl
33
34
~c~~9~j4
"' ' WO 91112303 PCI'1US91f~1934
!3
O1 poly(oxyalkylene) alcohol by reaction with phosgene.
02 The polyamine, encompassing diamines, provides the
03 product poly(oxyalkylene) aminocarbamate with, on the
04 average, at least about one basic nitrogen atom per
05 carhamate molecule, i.e., a nitrogen atom titratable by
06 strong acid. The golyamine preferably has a carbon-to-
07 nitrogen ratio of from about 1:1 to about 10:1. The
08 polyamine may be substituted with substituents selected
09 from hydrogen, hydrocarbyl groups of from 1 to about 10
carbon atoms, acyl groups of from 2 to about 10 carbon
11 atoms, and monoketone, monohydroxy, mononitro, mono-
12 cyano, alkyl and alkoxy derivatives of hydrocarbyl
13 groups of from 1 to 10 carbon atoms. It is preferred
14 that at least one of the basic nitrogen atoms of the
polyamine is a primary or secondary amino nitrogen. The
16 polyamine component employed in the present invention
17 has been described and exemplified more fully in U.S.
18 Patent No. 4,191,537.
19
Hydrocarbyl, as used in describing the hydrocarbyl
21 poly(oxyalkylene) and amine components used in this
22 invention, denotes an organic radical composed of carbon
23 and hydrogen which may be aliphatic, alicyclic, aromatic
24 or combinations thereof, e.g., aralkyl. Preferably, the
hydrocarbyl group will be relatively free of aliphatic
26 unsaturation, i.e.. ethylenic and acetylenic, particu-
27 lady acetylenic unsaturation. The more .preferred poly-
2g amine finding use within the scope of the present inven-
29 tion is a polyalkylene polyamine, including alkylene-
diamine, and including substituted polyamines, e.g.,
31 alkyl and hydroxyalkyl-substituted polyalkylene poly-
32 amine. Preferably, the alkylene group contains from 2
33 to 6 carbon atoms, there being preferably from 2 to 3
34 carbon atoms between the nitrogen atoms. Examples of
W(D 91/2303 PC'f/US91/00~9a4
l l~
O1 such polyamines include ethylenediamine, diethylene tri-
02 amine, triethylene tetramine, di(trimethylene) triamine,
03 dipropylene triamine, tetraethylene pentamine, etc.
04 Among the polyalkylene polyamines, polyethylene poly-
05 amine and polypropylene polyamine containing 2-12 amine
06 nitrogen atoms and 2-24 carbon atoms are especially pre-
0? ferred and in particular, the lower ;polyalkylene poly-
08 amines, e.g., ethylenediamine, diethylene triamine,
09 propylene diamine, dipropylene triamine, etc., are most
preferred.
11
12 C. The Aminocarbamate
13
14 The poly(oxyalkylene) aminocarbamate fuel additive used
in compositions of the present invention is obtained by
16 linking the amine component and the poly(oxyalkylene)
17 component together through a carbamate linkage, i.e.,
18
19
-°'°(°)-~'w
21
22 wherein the oxygen may be regarded as the terminal
23 hydroxyl oxygen of the poly(oxyalkylene) alcohol
24 component, and the carbonyl group -C(°)-, is preferably
Provided by a cougling agent, e.g., phosgene. In the
2~ preferred method of preparation, the hydrocarbyl
27 Poly(oxyalkylene) alcohol is reacted with phosgene to
28 Produce a chloroformate and the chloroformate is reacted
29 with the polyamine. The carbamate linkages are formed
as the poly(oxyalkylene) chains are bound to the
31 nitrogen of the polyamine through the oxycarbonyl group
32 of the chloroformate. Since there may be more than one
33 nitrogen atom of the polyamirie which is capable of
34 reacting with the chloroformate, the aminocarbamate
contains at least one hydrocarbyl poly(oxyalkylene)
~'~~~J
iy~ 91/I2303 1P(.'T/US91/00934
/7 .
0I polymer chain bonded through an oxycarbonyl group to a
02 nitrogen atom of the polya~aine, but the carbonate may
03 contain from 1 to 2 or more such chains. It is pre-
04 (erred that the hydrocarbyl poly(oxyalkylene) amino-
05 carbamate product contains on the average, about 1
06 poly(oxyalkylene) chain per molecule (i.e., is a
07 monocarbamate), although it is understood that this
OS reaction route may lead to mixtures containing
09 appreciable amounts of di or higher poly(oxyalkylene)
chain substitution on a polyamine containing several
11 reactive nitrogen atoms. A particularly preferred
12 aminocarbamate is alkylphenyl poly(oxybutylenep amino-
13 carbamate, wherein the amine moiety is derived from
I4 ethylene diamine or diethylene triamine. Synthetic
methods to avoid higher degrees of substitution, methods
16 of preparation, and other characteristics of the amino-
17 carbamates used in the present invention are more fully
1g described and exemplified in U.S. Patent No. 4,191,537.
19 '
The In hector Detergent
21
22 The injector detergent employed in the homogeneous fuel
23 additive composition of the present invention is a
24 branched-chain hydrocarbyl amine having at least one basic
ZS nitrogen atom and an average molecular weight of about 300
26 to about 700, and wherein the hydrocarbyl moiety is derived
27 from polymers of CZ to C6 olefins.
28
29 Tn the amine injector detergent, the branched-chain
hydrocarbyl group will ordinarily be prepared by polymec-
31 izing olefins of from 2 to 6 carbon atoms fethylene being
32 copolymerized With another olefin so as to provide a
33 branched-chain). The branched chain hydrocarbyl group will
34 generally have at least I branch per 6 carbon atoms along
~~~~~5~?
WO 91/12303 PGT/gJ591/OO~j4
~$
O1 the chain, preferably at least 1 branch per 4 carbon atoms
02 along the chain and, more preferably, at least 1 branch per
03 2 carbon atoms along the chain. The preferred branched-
04 chain hydrocarbyl groups are polypropylene and polyiso-
05 butylene. The branches will usually be of from 1 to 2
06 carbon atoms, preferably I carbon atom, that is, methyl. In
07 general, the branched-chain hydrocarbyl group will contain
08 from about 20 to 40 carbon atoms.
09
IO In most instances, the branched-chain hydrocarbyl amines are
1I not a pure single product, but rather a mixture of compounds
1Z having an average molecular weight. Usually, the range of
13 molecular weights will be relatively narrow and peaked near
14 the indicated molecular weight.
I6 The amino component of the branched-chain hydrocarbyl amines
17 may be either a monoamine or a polyamine. The monoamine or
I8 polyamine component embodies a broad class of amines having
19 from I to 10 amine nitrogen atoms and from Z to 40 carbon
atoms with a carbon to nitrogen ratio between about 1:I and
21 10:1. In most instances, the amine component is not a pure
Z2 single product, but rather a mixture of compounds having a
23 major quantity of the designated amine. For the more
24 complicated polyamines, the compositions will be a mixture
of amines having as the major groduct the compound indicated
26 and having minor amounts of analogous compounds.
2?
28 When the amine component is a polyamine, it will preferably
2g be a polyalkylene polyamine, including alkylenediamine.
preferably, the alkylene group will contain from 2 to 6
31 carbon atoms, more preferably from 2 to 3 carbon atoms.
32 examples of such polyamines include ethylene diamine,
33 diethyl,ene triamine, triethylene~tetramine and tetraethylene
34 pentamine.
CA 02049954 2002-05-16
19
O1 A particularly preferred branched-chain hydrocarbyl amine is
02 polyisobutenyl ethylene diamine.
03
04 The branched-chain hydrocarbyl amine injector detergents
05 employed in the fuel additive composition of the invention
06 are prepared by conventional procedures known in the art.
07 Such branched-chain hydrocarbyl amines and their prepa-
08 rations are described in detail in U.S. Patent
09 Nos. 3,438,757; 3,565,804; 3,574,576; 3,848,056 and
3,960,515.
11
12 The Demulsifier
13
14 The demulsifier employed in the fuel additive composition of
the invention is a chemical agent which, when used in
16 relatively low concentrations in gasoline compositions, will
17 promote the rapid coalescence of emulsified water to the
18 point where it can be effectively removed from the bulk
19 hydrocarbon by means of static gravity assisted separation
in a quiescent storage tank. The demulsifier agent is
21 frequently a mixture of several chemical agents which in
Z2 proper combination afford the desired demulsifying charac-
23 teristics. These agents are typically selected from, but
24 are not restricted to, alkylphenol resins, polyoxyalkylene-
based fluids, alkylarylsulfonates, derivatives of fatty
26 acids, and the like. One.preferred demulsifier for use in
27 the composition of this invention is known as Tolad ~ T-326,
28 a commercially available demulsifier from Petrolite
29 Corporation, Tretolite Division, St. Louis, Missouri, which
comprises a mixture of oxyalkylated alkylphenol-formaldehyde
31 resins, polyoxyalkylene glycols, and sodium arylsulfonate in
32 heavy aromatic naphtha.
W~ 91/IZ303 P(.'T/US91/00934{.,1
as
O1 In selectiflg a proper fuel/water demulsifying agent, it is
02 important that the fuel, blended with an effective deposit
03 control amount of a fuel additive, be able to shed water or
04 become essentially emulsion-free within 15 to 30 minutes of
05 its contact with an aqueous phase. The fuel additive com-
06 position of this invention, being generally regarded as a
07 dispersant agent, also has the tendency to promote emulsion
48 formation when gasoline compositions containing the additive
09 composition are contacted with water. Demulsifiers. at
relatively low fuel concentrations, assist in the demulsifi-
11 cation of such emulsions and thereby help to clarify other-
12 wise cloudy wet fuels. It is important to note that
13 demulsifiers, when used in concentrations higher than about
14 25 pgm, can also promote emulsification. Hence, their
dosage must be carefully regulated and adjusted to the
16 physical/chemical characteristics of fuel compositions
17 containing the fuel additive components. Many demulsifiers
18 will satisfy this criterion but will nevertheless fail the
19 criterion of compatibility with the other components of the
fuel additive composition.
21
22 The Carrier Fluid
23
24 The carrier fluid employed in this invention is a chemically
inert hydrocarbon-soluble liquid vehicle which substantially
26 increases the nonvolatile residue (NVR), or solvent-free
27 liquid fraction of the fuel additive composition while not
28 overwhelmingly contributing to octane requirement increase.
29 The carrier fluid may be a natural or synthetic oil, such as
3p mineral oil, refined petroleum oils, synthetic polyalkanes
31 and alkenes, synthetic polyoxyalkylene derived oils, and the
32 like, as described, for example, in U.S. Patent
33 ~lo. 4,191,537 to Lewis. These carrier fluids are believed
34
f.-
WO 91/123(63 ~ 1'CT/US91/0093a
O1 to act as a carrier for the dispersant and detergent and to
02 assist in removing and retarding deposits.
03
04 The carrier fluid employed in the instant invention must
05 also be capable of forming a homogeneous mixture with the
06 other components of the present fuel additive composition.
07 Examples of suitable carrier fluids include Chevron Neutral
08 Oil 5008 and Chevron Neutral Oil 600P, available from
09 Chevron U.S.A. Inc., San Francisco, California.
11 Fuel Com ositions
12
13 The fuel additive composition of the present invention will
1q generally be employed in a hydrocarbon distillate fuel
boiling in the gasoline or diesel range. The proper concen-
18 tration of this additive composition necessary in order to
1~ achieve the desired detergency and dispersancy varies
18 depending upon the type of fuel employed, the presence of
1g other additives, and the like. In general, however, from
about 400 to 1,200 parts per million (ppm) of the instant
21 fuel additive composition in the base fuel is needed to
22 achieve the best results. In terms of individual compo-
23 vents, fuel compositions containing the homogeneous fuel
2q additive composition of the invention will generally contain
about 100 to 225 ppm of the aminocarbamate dispersant, about
26 10 to 70 ppm of the hydrocarbyl amine injector detergent,
27 about 5 to 25 ppm of the demulsifier and about 250 to
28 800 ppm of the carrier fluid.
29
The deposit control fuel additive composition of the present
3I invention may also be formulated as a concentrate, using an
32 inert, stable oleophilic organic solvent boiling in the
33 range of about 150° to 400°F. Preferably, an aliphatic or an
3q aromatic hydrocarbon solvent is used, such as benzene,
~~~~~5~~ .
WO 91/12303 PCT/US91/OOys4
as
01 toluene, xylenes, or higher-boiling aromatics or aromatic
02 thinners. Aliphatic alcohols of about 3 to 8 carbon atoms,
03 such as isopropanol, isobutylcarbinol, n-butanol, and the
04 like, in combination with hydrocarbon salveents are also
05 suitable for use with the additive composition of the
06 invention. In the fuel concentrate, the amount of the
07 instant additive composition will be ordinarily at least 5
08 percent by weight and generally not exceed 50 percent by
09 weight, preferably from 10 to 30 weight percent.
11 In gasoline fuels, other fuel additives may also be included
1Z such as antiknock agents, e.g., methylcyclopentadienyl
13 manganese tricarbonyl, tetramethyl or tetraethyl lead, tert-
14 butyl methyl peroxide and various oxygenates, such as
methanol, ethanol and methyl t-butyl ether. Also included
16 may be lead scavengers such as aryl halides, e.g., dichloro-
17 benzene or alkyl halides, e.g., ethylene dibromide. Addi-
18 tionally, antioxidants and metal deactivators may be
19 present.
21 In diesel fuels, other well-known additives can be employed
Z2 such as pour point depressants, flow improvers, cetane
23 improvers, etc.
24
The following examples are offered to specifically
26 illustrate this invention. These examples and illustrations
27 are not to be construed in any way as limiting the scope of
28 this invention.
29
31
32
33
34
~r0 91/12303 PCf/US91/0093~
?..3
O1 EXAMPLES
02
03 EXAMPLE 1
04
05 Preparation of an Aminocarbamate Dispersant
Useful in this Invention
06
~7 A dispersant useful in this invention was prepared in a
0'8 manner similar to that described in Lewis, U.S. Patent
Og No. 4,160,648, Examples 6-8, except that diethylene triamine
was used in place of ethylene diamine. In this example, a
11 tetrapropenyl phenol was reacted stepwise with butylene
12 oxide, phosgene, and diethylene triamine to afford a high
13 molecular weight tetrapropenyl polyloxybutylene)
14 aminocarbamate, referred to hereinbelow as a polyether amine
(PEA1.
16
17 EXAMPLE 2
18
19 A Hydrocarbyl Amine Injector
Detergent Useful in this Invention
21
22 An injector detergent (ID) was prepared in a manner similar
23 to that described by Honnen, U.S. Patent No. 3,438,757,
24 Example 2. In this example, a C30 polyisobutene having a
molecular weight of approximately 420 was reacted stepwise
2~, with chlorine and ethylene diamine to produce a
27 polyisobutene ethylene diamine adduct.
EXAMPLE 3
29
Carrier Fluids Useful in this Invention
31
32
33 Chevron Neutral Oil 5008 and Chevron Neutral Oil 600P were
34 used as carrier fluids (CF) in the examples hereinbelow.
Chevron Neutral Oil 500R.is a highly refined base oil having
WO 91!12303 ' a ~ PLT'/US911009~, .
O1 a pour point of -12°C (Max.) and a viscosity of 98.6 cSt at
02 40°C. Chevron Neutral Oil 600P is a highly refined base oil
03 having a pour point of 10°F (-12.2°C) and a viscosity of
04 129.5 cSt at 37.8°C.
05
06 EXAMPLE 4
07
08 A Demulsifier Useful in this Invention
09
The demulsifier (D) used in these examples to illustrate the
!I present invention was a commercially available demulsifier
12 (from Petrolite Corporation, Tretolite Division, St. Louis,
13 MO) identified by the manufacturer as Tolad ~ T-326. This
14 demulsifier .comprises a mixture of oxyalkylated alkylphenol-
formaldehyde resins, polyoxyalkylene glycols, and sodium
16 arylsulfonate (1 to S weight percent) in heavy aromatic
17 naphtha (30 to 60 weight percent). Tolad ~ T-326 is
18 reported to have a flash point, SPCC, of 114°F, a pour
19 point, ASTM D-97, of 5°F, and a viscosity of 263 SUS at
60°F.
21
22 EXAMPLE 5
23
24 Demulsibility Test
26 The procedure described by ASTM Method D-1094 was used to
27 test demulsibility. Here, the fuel phase and the interface
28 are rated for clarity and for persistence of an interfacial
29 emulsion layer. The fuel additive compositions were tested
and rated numerically, on a scale from one to four. The
31 number "one" was the highest rating for clarity, and "one"
32 was the highest rating for persistence of an interfacial
33 emulsion layer.
34
WO 91!12303 PCTlUS91/00934
O1 The fuel additive composition of this invention, exemplified
02 by Sample 6A below, met the requirement of a rating of one,
03 on both these tests.
04
05 EXAMPLE 6
06
07 Preparation of Fuel Additive Compositions
08
Og Two fuel additive compositions were prepared. 150 parts of
the polyether amine of Ex. 1, 25 parts of the injector
11 detergent of Ex. 2, 12 parts of a demulsifier, 212 parts of
12 Chevron Solvent 25, (which is a mixture of C-9 blending
13 aromatics available from Chevron U.S.A. Inc., San Francisco,
!q California') and 450 parts of Chevron Neutral Oil 5008
(Ex. 3) were mixed at room temperature with stirring in a
16 200 ml flask.
17
18 Sample 6A contained Tolad O T-326 (as described in Ex. 4) as
1g the demulsifier. Sample 6B contained L-1562 as the demulsi-
fier. L-1562 is a commercially available demulsifier pur-
21 chased from Petrolite Corporation, St. Louis, M0. A third
2Z additive composition, Sample 6C, contained oleyl amine as
23 the injector detergent, and is shown for comparison pur-
24 poses. Oley1 amine is a low molecular weight straight chain
Clg primary amine.
26
a~ EXAMPLE 7
Z8
Compatibility Test
31 The compatibility test used was a modification of the
32 procedure described by ASTM Method D-2273, except that,
33 since a significant amount of diluent solvent (Chevron
3q Solvent 25, a mixture of C-9 blending aromatics) was already
~Q~~°~~
!y0 91/12303 PC,'T/US91/00r:~4
O1 present in these compositions, this test was gerformed with-
02 out further dilution. The test was performed in two parts,
03 In Part A, the samples prepared by the procedure of
04 Example 6 were held at ambient or room temperature (about
05 20-25°C) for 24 hours. Each sample was then visually
06 inspected for a secondary phase. If a secondary phase was
07 observed, the sample was centrifuged and the volume percent
08 of the secondary phase determined.. If no secondary phase
09 was observed, Part B of this test was performed.
11 In Part B, the samples were cooled to 0°P and held at this
12 temperature for 24 hours. Each sample was then visually
13 inspected for a secondary phase. If a secondary phase was
14 observed, the sample was centrifuged and the volume percent
of the secondary phase determined.
16
17 The results are reported in terms of volume percent of
18 secondary phase sediment after centrifuging, which was
I9 either a liquid, a solid or a combination. Levels of
sediment (or secondary phase) that exceed 0.005 vol.~ are
21 considered unacceptable.
22
23 The fuel additive composition of this invention (Sample 6A)
24 does not have any measurable volume percent of a secondary
phase under these test conditions. However, when L-1562 was
26 used as the demulsifier (Sample 6B),' or when oleyl amine was
Z.7 used as the injector detergent (Samgle 6C), significant and
28 unacceptable levels of a secondary phase were observed.
29
31
3Z _
33
34
~~~~~54
.-
-~ WO 91/12303 PCTlUS91l00939
a~
01 Vol. %
OZ Fuel Additive Composition Secondar~Phase
Part A Part B
03 (20-25°C) (0°F)
04 Sample 6A.: 150 parts PEA (Ex 1) e0.005 e0.005
05 25 parts ID (Ex 2)
06 450 parts CF (Ex 3,
Chevron 500R)
p7 222 parts Chev. Sol. 25
08 12 parts T-326
09 Sample 6a.: 150 parts PEA (Ex 1) 0.75 -
(Comparative) 25 parts ID (Ex 2)
450 parts CF (Ex 3,
1l Chevron 500R)
12 212 parts Chev. Sol. 25
12 parts L-1562
I3
14 Sample 6C.: 150 parts PEA (Ex 1) e0.005 0.05
(Comparative) 25 parts oleyl amine
450 parts CF (Ex 3,
16 Chevron 500R)
212 parts Chev. Sol. 25
1~ ~ 12 parts T-326
18 For Sample 6B, a liquid second phase was observed at ambient
i9 temperature showing the incompatibility of the demulsifier
with the other components of the fuel additive composition.
21
22 Sample 6C, containing oleyl amine as an injector detergent,
23 was centrifuged after cooling to 0°F and showed a small
24 volume (0.05 vol.%) of an insoluble solid sediment. Thus it
failed the criterion that sediment levels must not exceed
26 0 005 vol.%.
27
28 _EXAMPLE 8
29
Intake Valve Deposit Test
3i
3Z An unleaded regular grade gasoline was additized with fuel
33 additive packages of this invention such that the fuel
34 contained the following ingredients:
2O~~~Jt
WO 91/123(13 PCT/US9I100~:
:;'.
a$ ,
O1
02 8A: 150 ppm of PEA (Ex 1)
25 ppm of ID (Ex 2)
03 450 ppm of CF (Ex 3, Chevron600P)
04 12 ppm of D (T-326)
05 88: 150 ppm of PEA (Ex 1)
06 25 gpm of ID (Ex 2)
450 ppm of CF (Ex 3, Chevron500R)
07 12 ppm of D (T-326)
A8
09 The gasolines were tested for intake valve keep-clean
effectiveness using a procedure which utilizes a 1981
11 Pontiac 2.5-liter engine mounted upon an engine test stand,
12 and run for 90 hrs. This test simulates a type of severe
13 field test service characterized by light load driving
14 conditions. The effectiveness of an additive package is
determined by averaging the weights of accumulated intake
16 valve deposits obtained by the end of test, and comparing
17 these results with those obtained using identical test
18 conditions and the unadditized fuel. A good fuel additive
19 package capable of complete intake system keep-clean
performance will typically reduce base gasoline intake valve
21 deposits.
22
23 Using the above test conditions, the unadditized base fuel
24 test produced, on average, 1,090 milligrams of deposits per
intake valve. The same gasoline containing a fuel additive
26 package of this invention using Chevron Neutral Oil 600P,
27 Example 8A, gave on average 23 milligrams of deposits per
28 intake valve. When the above comparison was made between
29 base fuel and an addftized fuel containing Chevron Neutral
Oil 5008, Example 88, we observed an average of 299 milli-
31 grams of intake valve deposits. These results are
32 summarized below:
33 '
3~
~~~~9~~ 4
Pcrevs9ieoo9~a
WO 91e1Z343 act
O1 Fuel Blend~Containin~ Av. Deposit wgts.
02
03 No Additive (Base Case) 1090 mg
8A 23 mg
04
8B 299 mg
05
06
Oy In both 8A and 8B, the average deposit weight is well below
Og the base case, showing the effectiveness of the fuel
~g additive composition of the invention.
11 EXAMPLE 99
12
13 -Octane Requirement Increase Test
14
This test measures the potential that any gasoline additives
16 may have in upsetting the octane requirements of gasoline
operated engines. Over time, due to the buildup of deposits
1g in the combustion chamber, higher octane gasoline is
1g required to minimize engine knock. Unadditized gasolines
contribute a baseline level of deposits which typically
21 require a fuel having an octane value four numbers higher
22 than the initial fuel used to start the test in oxder to
23 minimize the increasing engine knock condition. Gasoline
24 additives contribute to this problem to different degrees,
and the magnitude of this contribution can be measured by
26 comparisons with engine tests using additized fuel. The
difference of OItI observed between the tests is that addi-~
28 tional increment of increased octane number required to
2g further minimize engine knock and is generally referred to
as the octane requirement increase attributable to the
31 gasoline additive package itself. This value is typically
32 referred to as the "additive OFtI number".
33
34
~0~~~~~~
W~ 91/12303 PCT/I1~91/OOd ~v
O1 This procedure utilizes a 1975 Toyota 2.2-liter engine
02 mounted on an engine stand and equipped with a control
03 system to carefully regulate test conditions and engine
04 operating cycles. The engine is first run for fifteen hours
05 on a relatively clean-burning, additive-free alkylate fuel.
06 At this time, the octane requirement is determined, and the
0? fuel is switched to a mixture of~70% unleaded regular
OS gasoline and 30% of FCC Heavy gasoline. The FCC Heavy
09 component is employed to increase the rate of combustion
chamber deposit accumulation during this phase of the test.
11 After 110 hours of additional engine operation, the final
I2 octane requirement measurement is made.
13
14 When tested in this~manner, the fuel additive package of
this invention contributed one half of one octane number
I6 more than the octane requirement observed for the unaddi-
1? tized fuel (Test 9A). This increase was significantly less
18 than that observed for a commercial gasoline additive
19 package consisting of a heavy polybutene amine made from a
polybutene containing, on average, 100 carbons per molecule,
21 and having an average molecular weight of about 1450, which
22 is reacted stepwise with chlorine and ethylene diamine, and
23 a large dose of carrier oil (Test 9B).
24 Increase
Fuel Containing: ORI Number Over Base
26 Base: No Additive 4.0 0
2? Test 9A: 150 ppm PEA (Ex 1) 4.5 0.5
28 25 ppm ID (Ex 2)
29 600 ppm CF (Ex 3,
Chevron SOOR)
12 ppm D (T-326)
31 (Ex 4)
3Z Test 9B: 250 ppm F~eavy 7.0 3.0
33 Polybutene Amine -
1000 ppm CF (Ex 3,
34 'Chevron 500R)
