U.S. patent application number 10/483931 was filed with the patent office on 2005-06-09 for emulsified fuel compositions prepared employing emulsifier derived from high polydispersity olefin polymers.
Invention is credited to Filippini, Brian B., Johnson, John R., Koch, Frederick W, Pudelski, John K..
Application Number | 20050120619 10/483931 |
Document ID | / |
Family ID | 23166143 |
Filed Date | 2005-06-09 |
United States Patent
Application |
20050120619 |
Kind Code |
A1 |
Koch, Frederick W ; et
al. |
June 9, 2005 |
Emulsified fuel compositions prepared employing emulsifier derived
from high polydispersity olefin polymers
Abstract
A water blended fuel composition comprising water, a normally
liquid fuel and an emulsifying amount of at least one of a
hydrocarbyl-substituted acylating agent and the reaction product of
said hydrocarbyl-substituted acylating agent and an amine, an
alcohol, a metal, reactive metal compound or a mixture of two or
more thereof, wherein the hydrocarbyl substituent is a polymerized
olefin having a polydispersity {overscore (M)}.sub.w/{overscore
(M)}.sub.n greater than 5. Such polyolefin substituents can be
prepared by polymerization of olefins in the presence of a calcined
catalyst comprising a partially or fully neutralized ammonium salt
of a heteropolyacid.
Inventors: |
Koch, Frederick W;
(Willoughby, OH) ; Filippini, Brian B.;
(Mentor-on-the-Lake, OH) ; Johnson, John R.;
(Euclid, OH) ; Pudelski, John K.; (Cleveland
Heights, OH) |
Correspondence
Address: |
The Lubrizol Corporation
Patent Administrator
Mail Drop 022B
29400 Lakeland Boulevard
Wickliffe
OH
44092-2298
US
|
Family ID: |
23166143 |
Appl. No.: |
10/483931 |
Filed: |
December 6, 2004 |
PCT Filed: |
June 21, 2002 |
PCT NO: |
PCT/US02/19608 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60302073 |
Jun 29, 2001 |
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Current U.S.
Class: |
44/301 |
Current CPC
Class: |
C10L 1/328 20130101 |
Class at
Publication: |
044/301 |
International
Class: |
C10L 001/32 |
Claims
What is claimed is:
1. An emulsified water-blended fuel composition comprising: (A) a
liquid hydrocarbon based fuel; (B) water; and (C) a minor,
emulsifying amount of at least one of a fuel-soluble
hydrocarbyl-substituted carboxylic acylating agent and a reaction
product of said acylating agent and at least one of ammonia, an
amine, an alcohol, a reactive metal, a reactive metal compound and
a mixture of two or more thereof, wherein the hydrocarbyl
substituent comprises a group derived from at least one polyolefin,
said polyolefin having {overscore (M)}.sub.w/{overscore (M)}.sub.n
greater than 5 resulting in a water in fuel emulsion.
2. The fuel composition of claim 1 wherein the hydrocarbon fuel (A)
is present at a level about 50 to about 99% by weight of the
water-blended fuel composition; water (B) is present at a level of
about 1 to about 50% by weight of the water-blended fuel
composition; and component (C) is present at a level of about 0.005
to about 10% by weight of the water-blended fuel composition.
3. The fuel composition of claim 1 wherein the polyolefin has
{overscore (M)}.sub.w/{overscore (M)}.sub.n ranges from about 6 to
about 20; wherein less than 5 percent by weight of the polyolefin
molecules have a number average molecular weight of less than 250;
wherein the polyolefin has {overscore (M)}.sub.n of at least about
800; wherein the polyolefin has at least about 30% terminal
vinylidene (I) groups.
4. The fuel composition of claim 1 wherein the polyolefin comprises
polyisobutylene.
5. The fuel composition of claim 1 wherein the polyolefin is
prepared by contacting (a) at least one C.sub.2-C.sub.30 olefin or
polymerizable derivative thereof with (b) a catalyst comprising a
partially or fully neutralized salt of a heteropolyacid, wherein
said catalyst has been calcined at from about 500.degree. C. for
about 1 to about 4 hours; and wherein the heteropolyacid is a
phosphotungstic acid, a phosphomolybdic acid, a silicotungstic acid
or a silicomolybdic acid.
6. The fuel composition of claim 5 wherein the salt is selected
from the group comprising ammonium salt, cesium salt and
combinations thereof.
7. The fuel composition of claim 1 wherein the polyolefin is
prepared by blending at least two polyolefin components having
different number average molecular weights, each such component
having a {overscore (M)}.sub.w/{overscore (M)}.sub.n of less than
5.
8. The fuel composition of claim 1 wherein the hydrocarbyl
substituted carboxylic acylating agent is selected from the group
comprising at least one monocarboxylic acid or a reactive
equivalent thereof; at least one hydrocarbyl-substituted succinic
acylating agent consisting of at least one hydrocarbyl substituent
and at least one succinic group wherein the hydrocarbyl substituent
is derived from a polyolefin; at least one hydrocarbyl-substituted
succinic acid or succinic anhydride represented correspondingly by
the formulae 6wherein R is a hydrocarbyl group.
9. The fuel composition of claim 1 wherein the hydrocarbyl
substituted carboxylic acylating agent is reacted with an amine
selected from the group comprising at least one monoamine; at least
one polyamine; at least one hydroxylamine and combinations
thereof.
10. The fuel composition of claim 8 wherein the hydroxyamine is
selected from the group consisting of primary, secondary and
tertiary alkanolamines represented correspondingly by the formulae
7and mixtures of two or more thereof; wherein in the above formulae
each R is independently a hydrocarbyl group of one to about 8
carbon atoms, and each R' is independently a hydrocarbylene group
of about 2 to about 18 carbon atoms.
11. The fuel composition of claim 1 wherein the hydrocarbyl
substituted carboxylic acylating agent is reacted with an alcohol
or water.
12. The fuel composition of claim 1 further comprising (D) an
emulsifying amount of at least one cosurfactant distinct from
(C).
13. The fuel composition of claim 12 wherein said at least one
cosurfactant has a hydrophilic-lipophilic balance (HLB) in the
range of about 1 to about 40 and is selected from the group
comprising at least one compound selected from the group consisting
of (a) Poly(oxyalkylene) compounds; (b) sorbitan esters; and (c)
fatty acid diethanolamides and combinations thereof.
14. The fuel composition of claim 12 wherein said at least one
cosurfactant comprises a fatty monocarboxylic acid containing from
about 8 to about 24 carbon atoms or an amine salt thereof.
15. The fuel composition of claim 12 wherein the at least one
cosurfactant comprises a hydrocarbyl substituted succinic acid or
anhydride containing from about 8 to about 24 carbon atoms in the
hydrocarbyl group.
16. The fuel composition of claim 1 further comprising (E) at least
one organic nitrate cetane improver and is present at a level of
about 0.05 to about 10% by weight of the water-blended fuel
composition.
17. The fuel composition of claim 15 wherein component (E)
comprises 2-ethylhexyl nitrate.
18. The fuel composition of claim 1 further comprising (F) at least
one antifreeze and is present at a level of about 0.1 to about 10%
by weight of the water-blended fuel composition.
19. The fuel composition of claim 1 further comprising (G) at least
one water-soluble, ashless, halogen-, boron-, and phosphorus-free
amine salt, distinct from component (C) and is present in amounts
ranging from about 0.001 to about 15% by weight of the emulsified
water-blended fuel composition.
20. The composition of claim 19 wherein the amine salt (G) is
selected from the group consisting of ammonium nitrate,
hydroxyammonium nitrate, methylammonium nitrate, ethylene diamine
diacetate, urea dinitrate, and mixtures of at least two
thereof.
21. An emulsified water blended fuel composition comprising: (A) a
normally liquid hydrocarbon based fuel boiling in the gasoline or
diesel fuel range; (B) water; (C) a minor emulsifying amount of the
reaction product of a hydrocarbyl substituted carboxylic acylating
agent and at least one of ammonia, an amine, an alcohol or a
mixture of two or more thereof wherein the hydrocarbon substituent
is derived from at least one polymerized olefin which has been
prepared by contacting (a) at least one C.sub.2-C.sub.30 olefin or
polymerizable derivative thereof with (b) a catalyst comprising a
partially or fully neutralized salt of a heteropolyacid, wherein
said catalyst has been calcined; and (G) at least one
water-soluble, ashless, halogen-, boron-, and phosphorus-free
ammonium or amine salt, distinct from component (C).
22. A method for operating an internal combustion engine comprising
fueling said engine with the fuel composition of claim 1.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to emulsified water-blended
fuel compositions, more particularly to water-blended fuel
compositions containing a liquid fuel, water, an emulsifier and
optionally, at least one of a cosurfactant, combustion modifier, an
organic cetane improver and an antifreeze.
[0002] Internal combustion engines, especially diesel engines,
using a mixture of water and fuel in the combustion chamber can
produce lower nitrogen oxides (NO.sub.x), hydrocarbon and
particulate emissions per unit of power output. Water is inert
toward combustion, but acts to lower peak combustion temperatures
which results in less NO.sub.x formation. Exhaust Gas Recirculation
(EGR) works on the same principle (i.e., inert materials tend to
lower peak combustion temperatures and hence reduce NO.sub.x).
Water can be separately injected into the cylinder, but hardware
costs are high. Water can also be added to the fuel as an emulsion.
However, emulsion stability has historically been a problem.
[0003] It would be advantageous to provide a water-blended fuel
composition that has improved emulsion stability. It would also be
advantageous to provide water-blended fuel compositions comprising
a reduced chlorine content or chlorine-free emulsifier composition.
The present invention provides such advantages.
[0004] U.S. Pat. No. 5,669,938, Schwab, Sep. 23, 1997, discloses a
fuel composition which consists of (i) a water-in-oil emulsion
comprising a major proportion of a hydrocarbonaceous middle
distillate fuel and about 1 to 40 volume percent water, (ii) a CO
emission, and particulate matter emission reducing amount of at
least one fuel-soluble organic nitrate ignition improver, and
optionally containing (iii) at least one component selected from
the group consisting of di-hydrocarbyl peroxides, surfactants,
dispersants, organic peroxy esters, corrosion inhibitors,
antioxidants, antirust agents, detergents, lubricity agents,
demulsifiers, dyes, inert diluents, and a cyclopentadienyl
manganese tricarbonyl compound.
[0005] European Patent EP 0 475 620 B1, Sexton et al., Aug. 11,
1995, discloses a diesel fuel composition which comprises: (a) a
diesel fuel; (b) 1.0 to 30.0 weight percent of water based upon
said diesel fuel; (c) a cetane number improver additive, present in
an amount up to, but less than, 20.0 weight percent based upon said
water, said additive being selected from an inorganic oxidizer, a
polar organic oxidizer and a nitrogen oxide-containing compound;
and (d) 0.5 to 15.0 wt. % based on the diesel fuel of a surfactant
system comprising (i) one or more first surfactants selected from
surfactants capable of forming a lower phase microemulsion at
20.degree. C. when combined with equal volumes of the fuel and
water at a concentration of 2 grams of surfactant per deciliter of
fuel plus water, which microemulsion phase has a volume ratio of
water to surfactant of at least 2; at least one said first
surfactant being an ethoxylated C.sub.12-C.sub.18 alkyl ammonium
salt of a C.sub.9-C.sub.24 alkyl carboxylic or alkylaryl sulfonic
acid containing 6 or more ethylene oxide groups; and (ii) one or
more second surfactants selected from surfactants capable of
forming an upper phase microemulsion at 20.degree. C. when combined
with equal volumes of the fuel and water at a concentration of 2
grams of surfactant per deciliter of fuel plus water, which
microemulsion phase has a volume ratio of water to surfactant of at
least 2; at least one said surfactant being an ethoxylated
C.sub.12-C.sub.18 alkyl ammonium salt of C.sub.9-C.sub.24 alkyl
carboxylic or alkylaryl sulfonic acid containing less than 6
ethylene oxide groups; the said first and second surfactants being
present in a weight ratio which forms with components (a), (b) and
(c) a single phase translucent microemulsion.
[0006] European patent publication EP 0 561 600 A2, Jahnke, Sep.
22, 1993, discloses a water in oil emulsion comprising a
discontinuous aqueous phrase comprising at least one
oxygen-supplying component (such as ammonium nitrate); a continuous
organic phase comprising at least one carbonaceous fuel; and a
minor emulsifying amount of at least one emulsifier made by the
reaction of:
[0007] (A) at least one substituted succinic acylating agent, said
substituted acylating agent consisting of substituent groups and
succinic groups wherein the substituent groups are derived from a
polyalkene, said acylating agents being characterized by the
presence within their structure of an average of at least 1.3
succinic groups for each equivalent weight of substituent groups,
and
[0008] (B) ammonia and/or at least one amine.
[0009] U.S. Pat. No. 5,047,175, Forsberg, Sep. 10, 1991, discloses
salt compositions which comprise: (A) at least one salt moiety
derived from (A)(I) at least one high-molecular weight
polycarboxylic acylating agent, said acylating agent (A)(I) having
at least one hydrocarbyl substituent having an average of from
about 20 to about 500 carbon atoms, and (A)(II) ammonia, at least
one amine, at least one alkali or alkaline earth metal, and/or at
least one alkali or alkaline earth metal compound; (B) at least one
salt moiety derived from (B)(I) at least one low-molecular weight
polycarboxylic acylating agent, said acylating agent (B)(I)
optionally having at least one hydrocarbyl substituent having an
average of up to about 18 carbon atoms, and (B)(II) ammonia, at
least one amine, at least one alkali or alkaline earth metal,
and/or at least one alkali or alkaline earth metal compound; said
components (A) and (B) being coupled together by (C) at least one
compound having (i) two or more primary amino groups, (ii) two or
more secondary amino groups, (iii) at least one primary amino group
and at least one secondary amino group, (iv) at least two hydroxyl
groups or (v) at least one primary or secondary amino group and at
least one hydroxyl group. These salt compositions are disclosed to
be useful as emulsifiers in water-in-oil explosive emulsions,
particularly cap-sensitive water-in-oil emulsions.
[0010] U.S. Pat. No. 4,708,753, Forsberg, Nov. 24, 1987, discloses
a water-in-oil emulsion comprising (A) a continuous oil phase; (B)
a discontinuous aqueous phase; (C) a minor emulsifying amount of at
least one salt derived from (C)(I) at least one
hydrocarbyl-substituted carboxylic acid or anhydride, or ester or
amide derivative of said acid or anhydride, the hydrocarbyl
substituent of (C)(I) having an average of from about 20 to about
500 carbon atoms, and (C)(II) at least one amine; and (D) a
functional amount of at least one water-soluble, oil-insoluble
functional additive dissolved in said aqueous phase; with the
proviso that when component (D) is ammonium nitrate, component (C)
is other than an ester/salt formed by the reaction of
polyisobutenyl (M.sub.n=950) succinic anhydride with diethanolamine
in a ratio of one equivalent of anhydride to one equivalent of
amine.
[0011] U.S. Pat. No. 3,756,794, Ford, Sep. 4, 1973, discloses an
emulsified fuel composition consisting essentially of (1) a major
amount of a hydrocarbon fuel boiling in the range of 20-400.degree.
C. as the disperse phase, (2) 0.3% to 5% by weight of an
emulsifier, (3) 0.75% to 12% by weight water, (4) 0.3% to 0.7% by
weight of urea as emulsion stabilizer and (5) 0.3% to 0.7% by
weight of ammonium nitrate.
[0012] PCT Patent Publication WO 00/15740 describes an emulsified
water-blended fuel composition comprising: (A) a hydrocarbon
boiling in the gasoline or diesel range; (B) water; (C) a minor
emulsifying amount of at least one fuel-soluble salt made by
reacting (C)(I) at least one acylating agent having about 16 to 500
carbon atoms with (C)(II) ammonia and/or at least one amine; and
(D) about 0.001 to about 15% by weight of the water-blended fuel
composition of a water-soluble, ashless, halogen-, boron-, and
phosphorus-free amine salt, distinct from component (C). In one
embodiment, the composition further comprises (E) at least one
cosurfactant distinct from component (C); in one embodiment, (F) at
least one organic cetane improver; and in one embodiment, (G) at
least one antifreeze.
[0013] PCT Patent Publication WO 01/00688 describes dispersants for
lubricants which are the reaction product of an amine, an alcohol,
or a mixture of two or more of two or more thereof, and a
hydrocarbyl-substituted acylating agent, wherein the hydrocarbyl
substituent comprises at least one polymerized olefin, the
resulting polyolefin having {overscore (M)}.sub.w/{overscore
(M)}.sub.n of greater than 4 or 5, preferably 6 or 7.5 to 20. The
polyolefin preferably has {overscore (M)}.sub.n of at least 1500,
and preferably at least 30% terminal vinylidene (I) groups.
[0014] Polyolefins have been prepared by heteropolyacid catalyzed
polymerization of olefinic compounds. U.S. Pat. No. 5,710,225,
Johnson et al., Jan. 20, 1998, discloses a method for producing
polymers by polymerization of olefins, by contacting a
C.sub.2-C.sub.30 olefin or a derivative thereof with a
heteropolyacid. The heteropolyacid catalyst can be partially or
fully exchanged with cations from the elements in groups IA, IIA
and IIIA of the periodic chart, Group IB-VIIB elements and Group
VIII metals, including manganese, iron, cobalt, nickel, copper,
silver, zinc, boron, aluminum, bismuth, or ammonium or
hydrocarbyl-substituted ammonium salt. The heteropolyacids can be
used in their initial hydrated form or they can be treated
(calcined) to remove some or all of the water of hydration.
Calcining is preferably conducted in air at a temperature of, for
instance, up to 500.degree. C. although temperatures much over
350.degree. C. generally do not provide much advantage. In the
resulting polymers, the combined terminal vinylidene and
.beta.-isomer content is preferably at least 30%.
[0015] It is often desirable to use highly reactive polyolefins to
prepare hydrocarbyl-substituted acylating agents (e.g., anhydrides)
by way of a thermal route rather than a chlorine catalyzed route.
The thermal route involves simply conducting the reaction at an
elevated temperature without the use of an added catalyst or
promoter. The thermal route avoids products containing chlorine.
The reactivity of the polyolefin is believed to be related to the
end group in the polymer with terminal olefins (terminal
vinylidene) and terminal groups capable of being isomerized
thereto, .beta.-isomers, being identified as the reactive
species.
[0016] The thermal route to substituted succinic anhydrides using
highly reactive polyisobutylenes (PIBs) has been discussed in
detail in U.S. Pat. Nos. 5,071,919, 5,137,978, 5,137,980 and
5,241,003.
[0017] Conventional PIB has terminal vinylidene content of roughly
5%. The terminal isomer groups of conventional PIB and high
vinylidene PIB are given in EP 0 355 895 and in the aforementioned
PCT Patent Publication WO 01/00688. High vinylidene materials can
contain at least 30 percent terminal vinylidene and .beta.-isomer
groups. In preferred cases the polyisobutylene can contain at least
50 percent terminal vinylidene groups, and more preferably at least
60 percent terminal vinylidene groups.
SUMMARY OF THE INVENTION
[0018] The present invention provides an emulsified water-blended
fuel composition comprising:
[0019] (A) a liquid hydrocarbon based fuel;
[0020] (B) water; and
[0021] (C) a minor emulsifying amount of at least one of a
fuel-soluble hydrocarbyl-substituted carboxylic acylating agent and
a reaction product of said acylating agent and at least one of
ammonia, an amine, an alcohol, a reactive metal, a reactive metal
compound and a mixture of two or more thereof, wherein the
hydrocarbyl substituent comprises at least one polyolefin, said
polyolefin having {overscore (M)}.sub.w/{overscore (M)}.sub.n
greater than 5.
[0022] In one embodiment, the composition further comprises (D) at
least one cosurfactant distinct from component (C); in one
embodiment, (E) at least one organic cetane improver; and in one
embodiment, (F) at least one antifreeze. In another embodiment, the
composition further comprises (G) a water-soluble, ashless (i.e.
metal-free), halogen-, boron-, and phosphorus-free amine salt,
distinct from component (C). The invention also relates to a method
for operating an internal combustion engine comprising fueling said
engine with the composition of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0023] The Normally Liquid Hydrocarbon Based Fuel (A)
[0024] The fuels of this invention include all normally liquid
hydrocarbon based fuels known in the art. By `normally liquid` is
meant a fuel which is liquid or liquefiable at normal operating
temperatures. For the purposes of this invention, `hydrocarbon
based` fuels are fuels containing hydrocarbon moieties. These fuels
may be purely hydrocarbon fuels. These fuels may also be
hydrocarbon moiety containing fuels further containing moieties
other than hydrocarbon moieties. Included are liquid fuels derived
from animal, vegetable mineral sources. The fuels also may comprise
mixtures of any of these fuels.
[0025] These fuels include gasoline meeting ASTM Specification
D-4814 (formerly ASTM Specification D-439, now discontinued),
diesel fuel meeting ASTM Specification D-975, heating oil meeting
ASTM Specification D-396, oxygenates, mixtures of predominantly
hydrocarbon fuels and oxygenates, biomass fuel, and synthetic
fuels.
[0026] Purely hydrocarbon fuels may be any and all
hydrocarbonaceous distillate fuels. These include, but are not
necessarily limited to heavy hydrocarbon fuels, hydrocarbons
boiling in the gasoline range and middle distillate oils, for
example, diesel oil and heating oils, kerosene, naphtha, synthetic
hydrocarbon fuels such as polyolefins, alkylated aromatic
hydrocarbon group containing fuels, hydrocarbon fuels obtained by
the Fischer-Tropsch process, and others. Fuels derived from mineral
sources such as coal and shale are contemplated. Further gas to
liquid fuels are included herein.
[0027] Hydrocarbon group containing fuels further containing groups
other than hydrocarbon groups include, but not limited to, alcohols
such as methanol, ethanol and the like, ethers such as diethyl
ether, methyl ethyl ether and the like, organo nitro compounds,
esters, such as fatty acid esters, particularly those derived from
vegetable sources such as corn and alfalfa, and the like.
[0028] Biomass fuels are derived from organic materials, such as
seeds. Processes for obtaining these oils from biomass are
described in numerous U.S. patents, many of which are listed in
U.S. Pat. No. 6,166,231 which is hereby incorporated herein by
reference for relevant disclosures of such oils and methods for
obtaining them. Examples of biomass fuels are vegetable oil, for
example, sunflower oil and rapeseed oils.
[0029] The diesel fuels that are useful with this invention can be
any diesel fuel or fuel oil. They include those that are defined by
ASTM Specification D396. In one embodiment the diesel fuel has a
sulfur content of up to about 0.05% by weight (low-sulfur diesel
fuel) as determined by the test method specified in ASTM D2622-87
entitled "Standard Test Method for Sulfur in Petroleum Products by
X-Ray Spectrometry." Any fuel having a boiling range and viscosity
suitable for use in a diesel-type engine can be used. These fuels
typically have a 90% point distillation temperature in the range of
about 300.degree. C. to about 390.degree. C., and in one embodiment
about 330.degree. C. to about 350.degree. C. The viscosity for
these fuels typically ranges from about 1.3 to about 24 centistokes
at 40.degree. C. These diesel fuels can be classified as any of
Grade Nos. 1-D, 2-D or 4-D as specified in ASTM D 975 entitled
"Standard Specification for Diesel Fuel Oils".
[0030] Useful diesel fuels include mineral oil derived fuels and
biomass derived fuels, such as vegetable oils. Diesel fuels can
contain alcohols and esters.
[0031] Mixtures of hydrocarbon based fuels and oxygenates include
mixtures of any of the aforementioned hydrocarbon based fuels with
any of alkanols, especially lower alkanols, and ethers, for
example, methyl-t-butyl ether, methyl-t-amyl ether,
dimethoxymethane and diethoxymethane, and particularly, lower
alkanols such as ethanol. The well known `gasohol` blend of
gasoline and ethanol is one example.
[0032] The normally liquid hydrocarbon based fuel is generally
present at a level ranging from about 50% to about 99% by weight of
the water blended fuel composition, more often from about 60% to
about 90%, often to about 80% by weight.
[0033] Water (B)
[0034] Water is present in amounts ranging from about 1% to about
50% by weight of the water blended fuel composition.
[0035] The Emulsifier (C)
[0036] The emulsifying agents of the present invention comprise an
emulsifying amount of at least one of a fuel-soluble
hydrocarbyl-substituted carboxylic acylating agent and a reaction
product of said acylating agent with at least one of ammonia, an
amine, an alcohol, a reactive metal, a reactive metal compound or a
mixture of two or more thereof, wherein the hydrocarbyl substituent
comprises a group derived from at least one polyolefin, said
polyolefin having {overscore (M)}.sub.w/{overscore (M)}.sub.n
greater than 5.
[0037] The hydrocarbyl substituted acylating agents have a
hydrocarbyl group substituent that is derived from a polyolefin,
with polydispersity and other features as described below.
Generally it has a number average molecular weight of at least 600,
700, or 800, to 5000 or more, often up to 1200, 1300, 1600, 2500 or
3000. Typically, less than 5% by weight of the polyolefin molecules
have {overscore (M)}.sub.n less than 250, more often the polyolefin
has {overscore (M)}.sub.n of at least 800. The polyolefin
preferably contains at least about 30% terminal vinylidene groups,
more often at least 60% and more preferably at least 75% or 85%
terminal vinylidene groups. The polyolefin has polydispersity,
{overscore (M)}.sub.w/{overscore (M)}.sub.n, greater than about 5,
more often from about 6 to about 20. The hydrocarbyl group is
typically derived from a polyolefin or a polymerizable derivative
thereof, including homopolymers and interpolymers of olefin
monomers having 2 to 30, to 6, or to 4 carbon atoms, and mixtures
thereof. In a preferred embodiment the polyolefin is polyisobutene.
Such polyolefins are prepared by the methods set forth in greater
detail herein.
[0038] The emulsifier, component (C), is present at a level ranging
from about 0.005 to about 15% by weight of the water blended fuel
composition.
[0039] Suitable olefin polymer hydrocarbyl groups, having suitable
polydispersity, can be prepared by heteropolyacid catalyzed
polymerization of olefins under certain conditions. Preparation of
polyolefins under such conditions is also described in PCT
Publication WO 01/00694.
[0040] Heteropolyacids are well known materials. Such catalysts can
exist as the free acid or as a salt of a heteropolyanion.
Heteropolyanions are polymeric oxoanions formed by a condensation
reaction of two or more different oxoanions, e.g.,
12WO.sub.4.sup.2-+HPO.sub.4.sup.2-+23H.sup.+.fwdarw.(PW.sub.12O.sub.40).su-
p.3-+12H.sub.2O
[0041] A variety of structures are known for these materials; they
can have, for instance, the so-called Keggin structure, wherein
twelve WO.sub.6 octahedral surround a central PO.sub.4 tetrahedron
(in the case where phosphorus is employed). Other structures and
related formulas are also known, including PW.sub.12O.sub.42,
PW.sub.18O.sub.62, P.sub.2W.sub.5O.sub.23, PW.sub.9O.sub.32,
PW.sub.6O.sub.24, P.sub.2W.sub.18O.sub.62, PW.sub.11O.sub.39, and
P.sub.2W.sub.17O.sub.61, where P and W are taken as representative
elements and the indicated structure is an ion with the appropriate
charge. The central atom of the Keggin structure, which is
typically phosphorus, as shown, can also be any of the Group IIIA
to Group VIIA (ACS numbering) metalloids or non-transition metals,
including P, As, Si, Ge, B, Al, Sb, and Te. The tungsten (W) in the
above formula fills the role known as the "poly atom," which can be
any of the Group VB or VIB transition metals, including W, V, Cr,
Nb, Mo, or Ta. Thus suitable materials include preferably
phosphomolybdates, phosphotungstates, silicomolybdates, and
silicotungstates. Other combinations selected from among the above
elements are also possible, including borotungstates,
titanotungstates, stannotungstates, arsenomolybdates,
teluromolbydates, aluminomolybdates, and phosphovanadyltungstates,
the latter representing a mixed material having a formula (for the
anion portion) of PW.sub.11VO.sub.40. The preferred material is a
phosphotungstate, which term generally encompasses both the acid
and the various salts, described below.
[0042] The heteropoly catalysts are active both as their acid form,
in which the anion is associated with the corresponding number of
hydrogen ions, in the fully salt form, in which the hydrogen ions
have been replaced by other cations such as metal ions, or in the
partially exchanged salt form, in which a portion of the hydrogen
ions have been thus replaced. For more detailed information on the
structures of heteropoly catalysts, attention is directed to
Misono, "Heterogeneous Catalysis by Heteropoly Compounds of
Molybdenum and Tungsten," Catal. Rev.--Sci. Eng., 29(2&3),
269-321 (1987), in particular, pages 270-27 and 278-280. In the
present invention, the hydrogen ions have been partially or fully
replaced by ammonium, that is the catalyst is a partially or fully
neutralized ammonium salt of a heteropolyacid. Moreover, the
catalyst has been calcined at about 300.degree. C. to about
500.degree. C.
[0043] Heteropoly acids are commercially available materials,
(e.g., Aldrich Chemical Company, #22,420-0). The salts are
similarly commercially available, including most notably ammonium
and cesium salts. Alternatively, they can be prepared from the acid
materials by neutralization with an appropriate amount of base.
Heteropoly acids are generally received in a hydrated form. They
can be successfully employed in this form (uncalcined) or as in the
present invention, they can be treated (calcined) to remove some or
all of the water of hydration, that is, to provide a dehydrated or
otherwise modified species, which in the context of the present
invention exhibits improved reactivity. Calcining can be conducted
by simply heating the hydrated material to a suitable temperature
to drive off the desired amount of water. The heating can be under
ambient pressure or reduced pressure, or it can be under a flow of
air or an inert gas such as nitrogen. The use of air ensures that
the acid is in a high oxidation state. The flow of air can be
across the surface of the catalyst, or for greater efficiency, it
can be through the bulk of the catalyst. The length of time
required for calcining is related to the equipment and scale, but
in one broad embodiment the calcining can be conducted over the
course of 5 minutes to 16 hours, more typically 30 minutes to 8
hours, and preferably 1 hour, 2 hours or even 3 hours, up to 4
hours. The upper limits of time are defined largely by the
economics of the process; times in excess of about 5 hours do not
generally provide much advantage.
[0044] The material which is calcined to prepare the catalysts
useful for preparing polymers for use in the present invention is
preferably an ammonium salt of H.sub.3PW.sub.12O.sub.40. Said
heteropolyacid preferably comprises a material represented by the
formula (NH.sub.4).sub.nH.sub.3-n- PW.sub.12O.sub.40 wherein,
before calcining, n is 2.5 or where n is 3, or mixtures thereof and
after calcining, n ranges from about 1.9 to less than 3.
[0045] Typical ammonium salts include
(NH.sub.4).sub.3PW.sub.12O.sub.40 and
(NH.sub.4).sub.2.5H.sub.0.5PW.sub.12O.sub.40. Each of these
materials, as well as mixtures these species, are suitable. While
generally the temperature of calcining will be in the range of
above 300.degree. C. to 500.degree. C. and preferably 375 to
475.degree. C., the optimum conditions will depend to some extent
on the particular ammonium salt which is selected. When the
starting salt is (NH.sub.4).sub.3PW.sub.12O.sub.40, it has been
found that relatively higher temperatures are desirable for
obtaining the most active catalyst. Therefore, such material is
preferably calcined at 450 to 475.degree. C. When the starting salt
is (NH.sub.4).sub.2.5H.sub.0.5PW.sub.12O.sub.40, desirable
calcining temperatures can be somewhat lower, namely, above 300 to
475.degree. C. and preferably above 375 to 475.degree. C. When the
calcining temperature is too low, the catalysts may be largely or
entirely inactive. This phenomenon is not fully understood; but,
without intending to limit the generality or scope of the
invention, it is believed that the high temperature calcining
serves to remove a portion of the ammonia from the catalyst,
thereby leading to a more active species. The time and temperature
of the calcining are believed to be interrelated to some extent, so
that use of temperatures in the lower ranges can be more effective
when the calcining is conducted for a longer period of time, and
vice versa, as will be apparent to the person skilled in the
art.
[0046] The catalyst can be employed as particles of the pure salt,
or it can be provided on a solid support of an inert material such
as alumina, silica/alumina, an aluminophosphate, a zeolite, carbon,
clay, or, preferably, silica. The source of the solid silica
support can be a colloidal silica, which is subsequently
precipitated during the catalyst preparation, or a silica which has
already been preformed into a solid material. The catalyst can be
coated onto the support by well-known catalyst impregnation
techniques, e.g., by applying the catalysts as a solution, followed
by drying, such as by spray drying or evaporation. If a support
such as silica is employed, the ratio of the active catalyst
component to the silica support will preferably be in the range of
0.5:99.5 to 50:50 by weight, preferably 3:97 to 40:60 by weight,
and more preferably 10:90 to 30:70 by weight.
[0047] Temperatures used for the polymerization of olefins suitable
for the present invention are preferably below 20.degree. C. and
more preferably below 10.degree. C. Preferred temperature ranges
are -30 to 20.degree. C., more preferably -20 to 10.degree. C. and
most preferably about -5.degree. C., which is the approximate
reflux temperature of isobutylene. The polymerization can be
conducted in a batch apparatus or using continuous apparatus, such
as a continuous stirred tank reactor or a tubular reactor, as will
be apparent to those skilled in the art. The residence time of the
polymerization reaction will vary with conditions including the
type of reactor, generally suitable residence times being from 5 or
10 to 60 minutes, preferably 20 to 40 minutes. The polymerization
can be conducted neat but is preferably conducted in the presence
of a substantially inert hydrocarbon solvent or diluent, such as
isobutane, pentane, hexane, octane, decane, kerosene, or Stoddard
Solvent, which will normally be removed by conventional means at
the conclusion of the reaction. The reaction using the catalysts of
the present invention will generally provide at least a 10%
conversion under these conditions, and preferably at least 20 or
25% conversion to polymer. More preferably, the batch and
continuous process is conducted to about 50-60% conversion of
monomer.
[0048] As noted hereinabove, the preferred polymers useful in
preparing the acylating agents, are polyisobutylenes having
{overscore (M)}.sub.n greater than 500. For the C.sub.4
isobutylene, this would correspond to an average degree of
polymerization (dp) of about 8.8. The preferred {overscore
(M)}.sub.n of polyisobutylene is at least 500 and more preferably
at least 1000 or 1500, and up to 5,000 or even greater, preferably
in the range of 2000 to 5000 or greater. It is also generally
preferred that the polymers (whether polyisobutylenes or other
polyolefins) do not have an extensive low molecular weight
fraction. That is, preferably they should comprise less than 10%,
5%, or 3% by weight of a fraction having a number average molecular
weight of less than 350, 500, or 800 units.
[0049] Such materials are particularly useful when used in
reactions to alkylate maleic anhydride. As well as isobutylene,
other C.sub.2-C.sub.30 olefins and derivatives thereof may be used
in this invention as well as styrene and derivatives thereof,
conjugated dienes such as butadiene and isoprene and non-conjugated
polyenes. The reaction to produce polymers may be run with mixtures
of starting olefins to form copolymers. The mole ratio of olefin
substrate to catalyst in this invention ranges from 1,000:1 to
100,000 to 1.
[0050] Useful polymers produced by the process of this invention
are derived from C.sub.2-C.sub.30 olefin monomers and mixtures
thereof and derivatives thereof. Under this terminology, styrene
and derivatives would be a C.sub.2-olefin substituted by a phenyl
group.
[0051] Useful olefin monomers from which the polyolefins used in
the present invention can be derived are polymerizable olefin
monomers characterized by the presence of one or more unsaturated
double bonds (i.e., >C.dbd.C<); that is, they are
monoolefinic monomers such as ethylene, propylene, butene-1,
isobutylene, and octene-1 or polyolefinic monomers (usually
diolefinic monomers) such as butadiene-1,3 and isoprene.
[0052] These olefin monomers are preferably polymerizable terminal
olefins; that is, olefins characterized by the presence in their
structure of the group R'--CH.dbd.CH.sub.2, where R' is H or a
hydrocarbyl group. However, polymerizable internal olefin monomers
(sometimes referred to as medial olefins) characterized by the
presence within their structure of the group: 1
[0053] can also be used to form the polyolefins. When internal
olefin monomers are employed, they normally will be employed with
terminal olefins to produce polyolefins which are interpolymers.
For purposes of this invention, when a particular polymerized
olefin monomer can be classified as both a terminal olefin and an
internal olefin, it will be deemed to be a terminal olefin. Thus,
for example, pentadiene-1,3 (i.e., piperylene) is deemed to be a
terminal olefin for purposes of this invention.
[0054] While the polyolefins used in the present invention
generally are hydrocarbon polyolefins, they can contain substituted
hydrocarbon groups such as lower alkoxy, and carbonyl, provided the
non-hydrocarbon moieties do not substantially interfere with the
functionalization reactions of this invention. Preferably, such
substituted hydrocarbon groups normally will not contribute more
than 10% by weight of the total weight of the polyolefins. Since
the polyolefin can contain such non-hydrocarbon substituents, it is
apparent that the olefin monomers from which the polyolefins are
made can also contain such substituents. Normally, however, as a
matter of practicality and expense, the olefin monomers and the
polyolefins will be free from non-hydrocarbon groups.
[0055] Although the polyolefins useful in the invention may include
aromatic groups (especially phenyl groups and lower alkyl- and/or
lower alkoxy-substituted phenyl groups such as
para-(tert-butyl)phenyl) and cycloaliphatic groups such as would be
obtained from polymerizable cyclic olefins or cycloaliphatic
substituted-polymerizable acrylic olefins, the polyolefins usually
will be free from such groups. Again, because aromatic and
cycloaliphatic groups can be present, the olefin monomers from
which the polyolefins are prepared can contain aromatic and
cycloaliphatic groups.
[0056] There is a general preference for polyolefins which are
derived from the group consisting of homopolymers and interpolymers
of terminal hydrogen olefins of 2 to 16 carbon atoms. A more
preferred class of polyolefins are those selected from the group
consisting of homopolymers and interpolymers of terminal olefins of
2 to 6 carbon atoms, more preferably 2 to 4 carbon atoms, and
especially 4 carbon atoms, most preferably, isobutylene.
[0057] Specific examples of terminal and internal olefin monomers
which can be used to prepare the polyolefins of this invention
include propylene; butene-1; butene-2; isobutylene; pentene-1;
hexene-1; heptene-1; octene-1; nonene-1; decene-1; pentene-2;
propylene-tetramer; diisobutylene; isobutylene trimer;
butadiene-1,2; butadiene-1,3; pentadiene-1,2; pentadiene-1,3;
isoprene; hexadiene-1,5; 2-chloro-butadiene-1,2;
2-methyl-heptene-1; 3-cyclohexylbutene-1;
2-methyl-5-propyl-hexene-1; pentene-3; octene-4;
3,3-dimethyl-pentene-1; styrene; 2,4-dichlorostyrene;
divinylbenzene; vinyl acetate; allyl alcohol; 1-methyl-vinyl
acetate; ethyl vinyl ether; and methyl vinyl ketone. Of these, the
hydrocarbon polymerizable monomers are preferred and of these
hydrocarbon monomers, the terminal olefin monomers are particularly
preferred.
[0058] Useful polymers include alpha-olefin homopolymers and
interpolymers, and ethylene/alpha-olefin copolymers and
terpolymers. Specific examples of polyalkenes include
polypropylene, polybutene, ethylene-propylene copolymer,
ethylene-butene copolymer, propylene-butene copolymer,
styrene-isobutylene copolymer, isobutylene-butadiene-1,3 copolymer,
propene-isoprene copolymer, isobutylene chloroprene copolymer,
isobutylene-(para-methyl)styrene copolymer, copolymer of hexene-1
with hexadiene-1,3, copolymer of 3,3-dimethyl-pentene-1 with
hexene-1, and terpolymer of isobutylene, styrene and piperylene.
More specific examples of such interpolymers include copolymer of
95% (by weight) of isobutylene with 5% (by weight) of styrene;
terpolymer of 98% of isobutylene with 1% of piperylene and 1% of
chloroprene; terpolymer of 95% of isobutylene with 2% of butene-1
and 3% of hexene-1; terpolymer of 60% of isobutylene with 20% of
pentene-1; and 20% of octene-1; terpolymer of 90% of isobutylene
with 2% of cyclohexene and 8% of propylene; and copolymer of 80% of
ethylene and 20% of propylene. U.S. Pat. No. 5,334,775 describes
polyolefin based polymers of many types and their monomer
precursors and is herein incorporated by reference for such
disclosure.
[0059] Relative amounts of end units in conventional and high
vinylidene polyisobutylenes can be determined from .sup.1H NMR
spectra made using a Bruker AMX 500 MHz instrument and UXNMRP
software to work up the spectra. CDCl.sub.3 is used as the solvent
with a sample concentration of approximately 0.10 g of sample
dissolved in 1.5 g solvent with tetramethylsilane (1%) added as a
reference. Band assignments in the NMR for the various isomers as
parts per million (ppm) downfield shift from tetramethylsilane are:
terminal vinylidene 4.68 and 4.89, .beta.-isomer 5.18,
tri-substituted 5.17 and 5.35, tetra 2.88.
[0060] The molecular weight of the polymers are typically
determined by gel permeation chromatography (GPC) (also known as
size exclusion chromatography) using a Waters.TM. 2000 instrument
run with tetrahydrofuran solvent (mobile phase). A series of 13
narrow molecular weight samples of polystyrene (m.w. 162 to
2,180,000) are preferably used as calibration standards, although
known polyisobutylene can also be used as a standard. {overscore
(M)}.sub.n (number average molecular weight) and {overscore
(M)}.sub.w (weight average molecular weight) are determined from
comparative elution volume data. Molecular weight values of the
polymers produced by the method of this invention will vary
according to their degree of polymerization (dp). The dp range for
products of this invention typically range from 6 to 350 or even
higher.
[0061] The polydispersity of the products useful in this invention
as determined by the ratio of {overscore (M)}.sub.w/{overscore
(M)}.sub.n have a value of at least 5 (polystyrene standard), and
may have a value of up to 20, or even greater, preferably up to 20,
depending upon reaction conditions. At any given reaction
temperature, the {overscore (M)}.sub.w/{overscore (M)}.sub.n is
controlled by the chemical nature of the catalyst as well as the
contact time of the olefin with the catalyst and the concentration
of the olefin during the reaction. Use of the calcined ammonium
catalysts of the present invention in the polymerization of
isobutylene leads to polyisobutylene having a polydispersity
typically greater than 5, or 6, often 7.5 to 20, more commonly 8 to
19 or 18. The polymers of suitable polydispersity are preferably
prepared directly, from a single polymerization reaction, as
opposed to by blending of different batches prepared from separate
polymerization reactions. However, it is possible to blend
different batches for convenience, each having suitably large
polydispersity, to arrive at a composite material having a
similarly large polydispersity.
[0062] It is also permitted to prepare polymeric mixtures of high
polydispersity by physical admixture of samples of polymers of
significantly different molecular weights, each sample individually
having a relatively small value for {overscore
(M)}.sub.w/{overscore (M)}.sub.n, that is, 4 or 5 or less. Such
blending may produce polymeric mixtures which are polymodal
(including bimodal) or otherwise non-uniform in their molecular
weight distribution.
[0063] The hydrocarbyl-substituted carboxylic acylating agents of
the present invention include carboxylic acids and their reactive
equivalents such as acid halides, anhydrides, and esters, including
partial esters. These may be mono or polycarboxylic acid materials
or reactive equivalents thereof.
[0064] In one embodiment, the hydrocarbyl substituted carboxylic
acylating agent comprises at least one hydrocarbyl-substituted
succinic acylating agent consisting of at least one hydrocarbyl
substituent and at least one succinic group wherein the hydrocarbyl
substituent is derived from a polyolefin, preferably,
polyisobutylene.
[0065] The hydrocarbyl-substituted succinic acid or succinic
anhydride can be represented correspondingly by the formulae 2
[0066] wherein R is a hydrocarbyl group.
[0067] The hydrocarbyl substituted carboxylic acylating agents are
prepared by the reaction of one or more of the above-described
polyolefins with one or more unsaturated carboxylic reagents. The
unsaturated carboxylic reagents include unsaturated carboxylic
acids per se and functional derivatives thereof, such as
anhydrides, esters, salts and acyl halides. The unsaturated
carboxylic reagents include mono-, di-, tri, or tetracarboxylic
acids. Examples of useful unsaturated monobasic acids include
acrylic acid, methacrylic acid, cinnamic acid, crotonic acid, and
2-phenylpropenoic acid. Polybasic unsaturated carboxylic acids
include maleic acid, fumaric acid, mesaconic acid, itaconic acid,
and citraconic acid; their anhydrides are preferred and maleic
anhydride is particularly preferred. Reactive equivalents of such
anhydrides include the above-mentioned derivative, e.g., acids,
esters, half esters, salts, and acyl halides, which can also serve
as carboxylic reagents. Another suitable acid is glyoxylic acid,
which can be reacted with the polymer as described in U.S. Pat. No.
5,912,213. Reactive equivalents of glyoxylic acid, including
esters, acetals, hemiacetals, as well as other materials described
in the foregoing U.S. patent, can also be used.
[0068] The acylating agents can be prepared by reacting one or more
of the polyolefins with, typically, a stoichiometric excess of a
carboxylic reagent such as maleic anhydride. Such reaction provides
a substituted carboxylic acylating agent having at least one
carboxylic group, preferably succinic groups. For each equivalent
weight of the hydrocarbyl group, there may be more than one
carboxylic group.
[0069] For purposes of this calculation, the number of equivalent
weight of substituent groups is deemed to be the number
corresponding to the quotient obtained by dividing the {overscore
(M)}.sub.n (number average molecular weight) value of the
polyalkene from which the substituent is derived into the total
weight of the substituent groups present in the substituted
acylating agent. Thus, if a substituted succinic acylating agent is
characterized by a total weight of substituent group of 40,000 and
the {overscore (M)}.sub.n value for the polyalkene from which the
substituent groups are derived is 2000, then that substituted
succinic acylating agent is characterized by a total of 20
(40,000/2000=20) equivalent weights of substituent groups.
[0070] Methods for preparing succinic acylating agents satisfying
these parameters, except for the use of the materials of the high
polydispersity, are described in U.S. Pat. No. 4,234,435. In
particular, this patent discloses (in column 19) a process for
preparing such materials by heating at a temperature of about
160.degree. C. to about 220.degree. C. a mixture comprising:
Polybutene characterized by a {overscore (M)}.sub.n value of about
1700 to about 2400, in which at least 50% of the total units
derived from butenes is derived from isobutene; one or more acidic
reactants of the formula 3
[0071] wherein R and R' are each --OH or when taken together, R and
R' are --O--; and chlorine.
[0072] Specific examples of preparation of such acylating agents
are set forth in Examples 1 through 9 of U.S. Pat. No.
4,234,435.
[0073] Other processes can be used, if desired, which do not employ
chlorine, and this is preferred if the presence of chlorine is
undesirable for environmental reasons. Bromine can be used in place
of chlorine; or the reactants can be heated together at 150 to 200
or 230.degree. C. in the absence of halogen. Moreover, it is
generally unnecessary to use chlorine when using high vinylidene
polyolefin reactants. Preparation using a so-called "thermal" route
is generally described in European Patent 355,895.
[0074] In the formation of the hydrocarbyl-substituted acylating
agent, the conditions for the reaction of the polyolefin with the
carboxylic reagent such as maleic anhydride, and the relative
concentrations of such components, should preferably be sufficient
that a majority of the olefin polymer has reacted with at least one
molecule of the acylating reagent. That is, it is preferred, for
optimum performance that no more than 30 percent by weight
unreacted polymer should remain unreacted in the resulting
acylating agent, preferably no more than 25 percent, and more
preferably no more than 20 percent, should remain. While reaction
of the polyolefin with the carboxylic reagent is preferably
conducted in the absence of chlorine, it is possible to prepare
hydrocarbyl substituted acylating agents by a process involving
chlorine. However, it is especially preferred that the preparation
of the hydrocarbyl substituted acylating agent be conducted in the
absence of chlorine. The polyolefins prepared employing
heteropolyacid catalysts facilitate the process. Determination of
conditions to assure a sufficient degree of reaction is within the
abilities of the person skilled in the art.
[0075] In one embodiment, the acylating agent is made by coupling
polyisobutene substituted succinic acids or anhydrides, the
polyisobutene substituent of the succinic acid or anhydride having
at least about 35 carbon atoms, preferably from about 50 to about
200 carbon atoms. The coupled acylating agent may be represented by
the formula 4
[0076] wherein each of R.sup.1 and R.sup.2 is a polyisobutene group
of at least about 35 carbon atoms and preferably at least about 50
carbon atoms up to about 200 carbon atoms.
[0077] In one embodiment, the succinic acids or anhydrides are
reacted with ethylene glycol, the ratio of equivalents being 1:
about (2.3-2.7), (which also corresponds to the same mole ratio)
and in one embodiment about 1:2.5. In another embodiment, the ratio
of equivalents is about (1.8-2.2):1, and in one embodiment about
2:1.
[0078] The hydrocarbyl substituted carboxylic acylating agents
alone may serve as emulsifier component (C). However, more often
the acylating agent is reacted with at least one of ammonia, water,
an amine, an alcohol, a reactive metal, a reactive metal compound
or a mixture of two or more thereof. When the acylating agent is
reacted with 2 or more of these reagents, they may be reacted
simultaneously, individually, or in any order.
[0079] Derivatives of Acylating Agents
[0080] In one embodiment, the emulsifier is the reaction product of
the hydrocarbyl substituted acylating agent with ammonia or an
amine. The amines useful for reacting with the acylating agent
include monoamines, polyamines, or mixtures of these.
[0081] The monoamines have only one amine functionality whereas the
polyamines have two or more. The amines can be primary, secondary
or tertiary amines. The primary amines are characterized by the
presence of at least one --NH.sub.2 group; the secondary by the
presence of at least one H--N< group. The tertiary amines are
analogous to the primary and secondary amines with the exception
that the hydrogen atoms in the --NH.sub.2 or H--N< groups are
replaced by hydrocarbyl groups. Examples of primary and secondary
monoamines include ethylamine, diethylamine, n-butylamine,
di-n-butylamine, allylamine, isobutylamine, cocoamine,
stearylamine, laurylamine, methyllaurylamine, oleylamine,
N-methyloctylamine, dodecylamine, and octadecylamine. Suitable
examples of tertiary monoamines include trimethylamine,
triethylamine, tripropyl amine, tributylamine, monoethyl
dimethylamine, dimethylpropyl amine, dimethylbutyl amine,
dimethylpentyl amine, dimethylhexyl amine, dimethylheptyl amine,
and dimethyloctyl amine.
[0082] In one embodiment, the amines are hydroxyamines. These
hydroxyamines can be primary, secondary, or tertiary amines.
Typically, the hydroxyamines are primary, secondary or tertiary
alkanolamines, or mixture thereof. Such amines can be represented,
respectively, by the formulae: 5
[0083] and mixtures of two or more thereof; wherein in the above
formulae each R is independently a hydrocarbyl group of 1 to about
8 carbon atoms, or a hydroxyl-substituted hydrocarbyl group of 2 to
about 8 carbon atoms and each R' independently is a hydrocarbylene
(i.e., a divalent hydrocarbyl) group of 2 to about 18 carbon atoms.
The group --R'--OH in such formulae represents the
hydroxyl-substituted hydrocarbylene group. R' can be an acyclic,
alicyclic, or aromatic group. Typically, R' is an acyclic straight
or branched alkylene group such as ethylene, 1,2-propylene,
1,2-butylene, 1,2-octadecylene, etc. group. When two R groups are
present in the same molecule they can be joined by a direct
carbon-to-carbon bond or through a heteroatom (e.g., oxygen,
nitrogen or sulfur) to form a 5-, 6-, 7- or 8-membered ring
structure. Examples of such heterocyclic amines include N-(hydroxyl
lower alkyl)-morpholines, -thiomorpholines, -piperidines,
-oxazolidines, -thiazolidines and the like. Typically, however,
each R is independently a lower alkyl group of up to seven carbon
atoms.
[0084] Suitable examples of the above hydroxyamines include mono-,
di-, and triethanolamine,
dimethylethanolamine(N,N-dimethylethanolamine),
diethylethanol-amine(N,N-diethylethanolamine),
di-(3-hydroxylpropyl)amine- , N-(3-hydroxyl butyl)amine,
N-(4-hydroxyl butyl)amine and N,N-di-(2-hydroxylpropyl) amine.
[0085] The reaction product of the hydrocarbyl substituted
carboxylic acylating agent and at least one of ammonia or an amine
may be a salt, an ester (when the amine is an alkanolamine), an
amide, an imide or a combination thereof. The salt may be an
internal salt involving residues of a molecule of the acylating
agent and the ammonia or amine wherein one carboxyl group of a
dibasic acidic acylating agent becomes ionically bound to a
nitrogen atom within the same group, or it may be an external salt
wherein the ionic salt group is formed with a nitrogen atom is not
part of the same molecule. In one embodiment, the hydrocarbyl
substituted carboxylic acylating agent is a hydrocarbyl substituted
succinic anhydride and the reaction product is a half-ester half
salt.
[0086] In another embodiment, the hydrocarbyl substituted
carboxylic acylating agent is a polyisobutenyl ({overscore
(M)}.sub.n 900 to about 2500) substituted succinic acid. The
emulsifier is prepared by reacting this succinic acid with 2
equivalents of alkanolamine.
[0087] The reaction between the hydrocarbyl substituted carboxylic
acylating agent and ammonia or amine is carried out under
conditions that provide for formation of the desired product. The
nature of the reaction and products obtained thereby will depend to
some extent on the nature of the carboxylic acylating agent.
Typically, the hydrocarbyl substituted carboxylic acylating agent
and the ammonia or amine are mixed together and heated to a
temperature in the range of from less than about 50.degree. C. to
about 250.degree. C., and in one embodiment from about 80.degree.
C. to about 200.degree. C., optionally in the presence of a
normally liquid, substantially inert organic liquid organic
solvent/diluent until the desired product has formed. To restrict
the reaction to primarily salt formation, it is necessary that the
acylating agent is a carboxylic acid. Employing a carboxylic acid,
the reaction is conducted at temperatures ranging from less than
about 80.degree. C. up to about 130.degree. C., preferably from
less than about 50.degree. C. up to about 110.degree. C. Commonly,
reactions to form salt can take place at ambient temperature.
[0088] Amides, esters and imides from anhydrides can form readily
at temperatures in excess of 50.degree. C., usually at greater than
80.degree. C., more often at greater than 90.degree. C., with imide
formation generally requiring even higher temperatures. Imides,
esters and amides from diacids prepared from anhydrides usually
require higher temperatures, for example greater than 120.degree.
C. for imides and up to about 250.degree. C. for esters. Ester
formation occurs when the amine is an alkanol amine.
[0089] Among preferred embodiments is the ester-acid salt prepared
from a dicarboxylic anhydride such as an alkyl succinic anhydride
and a tertiary alkanol amine. The amine and anhydride react readily
to form the monoester while the second carboxylic acid group
generated by the ring opening reacts with the tertiary amino
nitrogen to form salt.
[0090] In one embodiment, the hydrocarbyl substituted carboxylic
acylating agent and ammonia or amine are reacted in amounts ranging
from about 0.3 to about 3 equivalents of hydrocarbyl substituted
carboxylic acylating agent per equivalent of ammonia or amine; in
one embodiment the ratio is from about 0.5:1 to about 2:1 and in
another embodiment, about 1:1.
[0091] In one embodiment, the reaction product is made by reacting
a polyisobutene substituted succinic anhydride having an average of
from 1 to about 3 succinic groups for each equivalent of
polyisobutene group with diethanolamine, diethylethanolamine or
dimethylethanolamine in an equivalent ratio of 1 to about 0.4-1.25,
and in one embodiment, about 1:1.
[0092] In one embodiment, the reaction product is made by reacting
a polyisobutene substituted succinic anhydride having an average of
from 1 to about 3 succinic groups for each equivalent of
polyisobutene group with water in an equivalent ratio of 1 to about
4, and in one embodiment, about 1:1. That reaction product is
further reacted with an alkanols amine, preferably diethanolamine
in an equivalent ratio of about 1 acid to about 1 amine.
[0093] Amines used to prepare the emulsifiers can be polyamines as
disclosed in U.S. Pat. No. 4,234,435 at column 21, line 4 to column
27, line 50. They may also be heterocyclic polyamines or
alkylenepolyamines. Alkylenepolyamines are represented by the
formula H(R.sup.1)N-(Alkylene-N- (R.sup.1)).sub.nR.sup.1, where
each R.sup.1 is independently hydrogen or an aliphatic group or a
hydroxy-substituted aliphatic group; n is 1 to 10, 2 to 7, or 2 to
5, and the "Alkylene" group has 1 to 10, or 2 to 6, or 2 to 4
carbon atoms. Specific examples of such polyamines are the
ethyleneamines and polyethyleneamines, such as ethylenediamine,
triethylenetetramine, triethylenetetramine, tetraethylenepentamine,
pentaethylenehexamine and mixtures thereof, including complex
commercial mixtures which include cyclic condensation products.
Such materials are described in detail under the heading "Ethylene
Amines" in Kirk Othmer's Encyclopedia of Chemical Technology, 2d
Edition, Vol. 7, pages 22-37, Interscience Publishers, New York,
1965. Other amine mixtures include "polyamine bottoms" which is the
residue resulting from stripping of the above-described polyamine
mixture. In another embodiment, the polyamine can be a condensed
polyamine resulting form the condensation reaction of at least one
hydroxy compound with at least one polyamine reactant containing at
least one primary or secondary amino group. Such condensates are
described in U.S. Pat. No. 5,230,714. Similarly, amines can be
amino alcohols of any of a variety of well-known types.
[0094] For the purpose of this invention, an equivalent of amine is
that amount of amine corresponding to the total weight of amine
divided by the total number of nitrogens present. Thus, octyl amine
has an equivalent weight equal to its molecular weight;
ethylenediamine has an equivalent weight equal to one-half its
molecular weight, and aminoethylpiperazine has an equivalent weight
equal to one-third of its molecular weight.
[0095] The number of equivalents of acylating agent depends on the
number of carboxylic functions present in the acylating agent.
Conventional techniques are available for determining the number of
carboxylic functions (e.g., acid number, saponification number,
etc.) and thus, the number of equivalents of acylating agent
available to react with amine.
[0096] U.S. Pat. Nos. 3,172,892; 3,219,666; 3,272,746; and
4,234,435 are expressly incorporated herein by reference for their
disclosure with respect to the procedures applicable to reacting
the carboxylic compositions (acylating reagents) of this invention
with the amines as described above. In applying the disclosures of
these patents to the carboxylic compositions of the present
invention, the latter can be substituted for the high molecular
weight carboxylic acid acylating agents disclosed in these patents
on an equivalent basis.
[0097] Alcohols can be used in preparation of the emulsifiers of
the present invention resulting in ester group containing
compounds. Suitable alcohols can be aliphatic, cycloaliphatic,
aromatic, or heterocyclic, alcohols and can contain non-hydrocarbon
substituents of a type which do not interfere with the reaction of
the alcohols with the acylating agent to form the ester. The
alcohols can be monohydric alcohols such as methanol, ethanol,
isooctanol, dodecanol, and cyclohexanol, although they are
preferably polyhydric alcohols, such as alkylene polyols.
Preferably, such polyhydric alcohols contain 2 to 40 and more
preferably 2 to 20 carbon atoms; and 2 to 10 hydroxyl groups, more
preferably 2 to 6. Polyhydric alcohols include ethylene glycols
such as di-, tri- and tetraethylene glycols; propylene glycols;
glycerol; sorbitol; cyclohexane diol; erythritol; and
pentaerythritols, including di- and tripentaerythritol.
[0098] Alkanolamines can also serve as alcoholic reagents wherein
the hydroxyl group of the alkanolamine can react with the acylating
agent. As noted hereinabove, a wide variety of products can be
obtained, such as pure esters, ester-salts, ester amides, etc,
depending on the nature of the alkanolamine, etc.
[0099] Commercially available polyoxyalkylene alcohols can also be
employed as the alcohol component. Such materials include the
reaction products of various organic amines, carboxylic acid
amides, and quaternary ammonium salts with ethylene oxide. Some
such materials are available under the names Ethoduomeen T.TM., an
ethylene oxide condensation product of an N-alkyl alkylenediamine;
Ethomeen.TM., ethylene oxide condensation products of primary fatty
amines; Ethomid.TM., ethylene oxide condensates of fatty acid
amides, and Ethoquad.TM., polyoxyethylated quaternary ammonium
salts such as quaternary ammonium chlorides.
[0100] In one embodiment, the above described coupled acylating
agent with the ratio of about 1: about (2.3-2.7)), the above ratio
of about (1.8-2.2):1, is reacted with dimethylethanolamine in a
mole ratio of ethylene glycol to dimethylethanolamine of about 1:
(about 1.8-2.2), and in one embodiment about 1:2. Thus the coupled
di-ester/di-acid is converted into the di-salt by reaction of each
carboxylic acid group from the coupled acylating agent with one
equivalent of dimethylethanolamine.
[0101] The derivatives useful as emulsifiers can also be reaction
products of hydrocarbyl substituted carboxylic acylating agents
with reactive metals and reactive metal compounds.
[0102] Reactive metals and reactive metal compounds are those which
will form carboxylic acid metal salts with the carboxylic acylating
agents of this invention and those which will form metal-containing
complexes with the carboxylic derivative compositions produced by
reacting the acylating reagents with amines and/or alcohols as
discussed above. An extensive listing of useful metals and metal
compounds appears in U.S. Pat. Nos. 3,163,603 and 3,271,310.
Reactive metal compounds for the formation of complexes with the
reaction products of the acylating reagents of this invention and
amines are disclosed in U.S. Pat. No. 3,306,908. Complex-forming
metal reactants are those of the so-called transition or
coordination metals, i.e., they are capable of forming complexes by
means of their secondary or coordination valence.
[0103] The emulsifiers used in the present invention can be further
borated or treated with metallizing agents. Boration can be
effected by well-known techniques, in particular, by reaction of
the emulsifier with one or more boron compounds. Suitable boron
compounds include boric acid, borate esters, and alkali or mixed
alkali metal and alkaline earth metal borates. These metal borates
are generally a hydrated particulate metal borate and they, as well
as the other borating agents, are known in the art and are
available commercially. Typically the emulsifier is heated with
boric acid at 50-100.degree. C. or 100-150.degree. C. In a similar
way, the emulsifier can be metallized or treated with reactive
metal containing compounds, such as zinc compounds.
[0104] The Cosurfactants (D)
[0105] In addition to the presence of component (C) as an
emulsifier, the present composition can also contain other
emulsifiers, which may be present as cosurfactants. These
cosurfactants are present in emulsion enhancing/stabilizing
amounts. These cosurfactants are distinct from (C). These
emulsifiers/cosurfactants include, among others, ionic or nonionic
compounds, having a hydrophilic lipophilic balance (HLB) in the
range of about 2 to about 10, and in one embodiment about 4 to
about 8. Examples of these emulsifiers are disclosed in
McCutcheon's Emulsifiers and Detergents, 1993, North American &
International Edition. Some generic examples include alkanolamides,
amine salts of fatty carboxylic acids, alkylarylsulfonates, amine
oxides, poly(oxyalkylene) compounds, including block copolymers
comprising alkylene oxide repeat units (e.g., Pluronic.TM.),
carboxylated alcohol ethoxylates, ethoxylated alcohols, ethoxylated
alkyl phenyls, ethoxylated amines and amides, ethoxylated fatty
acids, ethoxylated fatty esters and oils, fatty esters, glycerol
esters, glycol esters, imidazoline derivatives, lecithin and
derivatives, lignin and derivatives, monoglycerides and
derivatives, olefin sulfonates, phosphate esters and derivatives,
propoxylated and ethoxylated fatty acids or alcohols or alkyl
phenyls, sorbitan derivatives, sucrose esters and derivatives,
sulfates or alcohols or ethoxylated alcohols or fatty esters,
sulfonates of dodecyl and tridecyl benzenes or condensed
naphthalenes or petroleum, sulfosuccinates and derivatives, and
tridecyl and dodecyl benzene sulfonic acids.
[0106] Hydrocarbyl substituted carboxylic acid and reactive sources
thereof, wherein the hydrocarbyl group contains from about 6, often
from about 8, up to about 24 carbon atoms, frequently up to about
18 carbon atoms, are also useful cosurfactants. These include mono-
and polycarboxylic compounds, In one embodiment, they comprise
fatty monocarboxylic acids and reactive equivalents thereof
containing from about 8 to about 24 carbon atoms. In another
embodiment, the cosurfactant may be a hydrocarbyl substituted
succinic acid or anhydride containing from about 8 to about 24
carbon atoms in the hydrocarbyl group. In one preferred embodiment,
the cosurfactant is a hexadecenyl substituted succinic acid or
anhydride.
[0107] Derivatives of the carboxylic acid as for (C) are also
useful cosurfactants. Amine salts of these fatty carboxylic acids,
particularly alkanol amine salts, are useful cosurfactants.
Preferred alkanolamine reactants are those that are water soluble.
In one preferred embodiment, a salt is obtained by mixing one mole
oleic acid with one mole diethylethanolamine. In another preferred
embodiment, the cosurfactant is an ester-salt obtained by reaction
of hexadecenyl substituted succinic anhydride with a dialkyl
alkanolamine, for example, diethyl ethanolamine. In another
preferred embodiment, the cosurfactant is a disalt obtained by
reaction of hexadecenyl substituted succinic acid with two moles of
diethyl ethanolamine.
[0108] The Organic Nitrate Cetane Improver (E)
[0109] In one embodiment of the present invention, the present
composition further comprises at least one organic cetane improver.
The organic nitrate cetane improver includes nitrate esters of
substituted or unsubstituted aliphatic or cycloaliphatic alcohols
which may be monohydric or polyhydric. Preferred organic nitrates
are substituted or unsubstituted alkyl or cycloalkyl nitrates
having up to about 10 carbon atoms, preferably from 2 to about 10
carbon atoms. The alkyl group may be either linear or branched, or
a mixture of linear or branched alkyl groups. Specific examples of
nitrate compounds suitable for use in the present invention include
methyl nitrate, ethyl nitrate, n-propyl nitrate, isopropyl nitrate,
allyl nitrate, n-butyl nitrate, isobutyl nitrate, sec-butyl
nitrate, tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate,
2-amyl nitrate, 3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate,
n-heptyl nitrate, n-octyl nitrate, 2-ethylhexyl nitrate, sec-octyl
nitrate, n-nonyl nitrate, n-decyl nitrate, cyclopentyl nitrate,
cyclohexyl nitrate, methylcyclohexyl nitrate, and
isopropylcyclohexyl nitrate. Also suitable are the nitrate esters
of alkoxy substituted aliphatic alcohols such as 2-ethoxyethyl
nitrate, 2-(2-ethoxy-ethoxy)ethy- l nitrate,
1-methoxypropyl-2-nitrate, 4-ethoxybutyl nitrate, etc., as well as
diol nitrates such as 1,6-hexamethylene dinitrate. While not
particularly preferred, the nitrate esters of higher alcohol may
also be useful. Such higher alcohols tend to contain more than
about 10 carbon atoms. Preferred are the alkyl nitrates having from
about 5 to about 10 carbon atoms, most especially mixtures of
primary amyl nitrates, mixtures of primary hexyl nitrates, and
octyl nitrates such as 2-ethylhexyl nitrate.
[0110] The concentration of the organic nitrate cetane improver in
the present composition can be any concentration sufficient to
counteract the reduction in cetane number caused by the addition of
water in the present water-blended fuel compositions. Generally,
addition of water to fuel acts to lower the cetane number of the
fuel. As a general rule of thumb, the cetane number of fuel goes
down by 1/2 unit per each 1% addition of water. Lowering of cetane
number results in ignition delay, which can be counteracted by the
addition of cetane enhancers/improvers. Generally, the amount of
organic nitrate cetane improver ester will fall in the range of
about 0.05 to about 10% and in one embodiment about 0.05 to about
1% by weight of the water-blended fuel composition.
[0111] The Antifreeze (F)
[0112] In one embodiment of the present invention, the composition
further comprises an antifreeze. The antifreeze is usually an
alcohol. Examples of suitable alcohols useful as an antifreeze for
the present invention include, but are not limited to ethylene
glycol, propylene glycol, methanol, ethanol, and mixtures
thereof.
[0113] The antifreeze can be present at any concentration
sufficient to keep the present composition from freezing within the
operable temperature range. In one embodiment, it is present at a
level of about 0.1% to about 10%, and in one embodiment, about 0.1
to 5% by weight of the water-blended fuel composition.
[0114] It is known that some of the materials described above may
interact in the final formulation, so that the components of the
final formulation may be different from those that are initially
added. For instance, certain ions can migrate to sites of other
molecules. The products formed thereby, including the products
formed upon employing the composition of the present invention in
its intended use, may not be susceptible of easy description.
Nevertheless, all such modifications and reaction products are
included within the scope of the present invention; the present
invention encompasses the composition prepared by admixing or using
the components described above.
[0115] Amine Salt (G)
[0116] Another optional component of the present composition is a
water-soluble, ashless (i.e. metal-free), halogen-, boron-, and
phosphorus-free amine salt, distinct from component (C). The term
"amine" here includes ammonia.
[0117] In one embodiment, the amine salt (G) is represented by the
formula
k[Z(NR.sub.3).sub.y].sup.y+nX.sup.p-
[0118] Wherein in the formula, Z is hydrogen, hydroxyl, alkoxyl, or
an organic neutral radical of 1 to about 8 carbon atoms, and in one
embodiment 1 to 2 carbon atoms, having a valence of y; each R
independently is hydrogen or a hydrocarbyl group of 1 to about 10
carbon atoms, and in one embodiment 1 to about 5 carbon atoms, and
in one embodiment 1 to 2 carbon atoms; X.sup.p- is an anion having
a valence of p; and k, y, n and p are independently at least 1,
provided that when Z is H, y is 1, and further provided that the
sum of the positive charge ky.sup.+ is equal to the sum of the
negative charge nX.sup.p-, such that the amine salt (G) is
electrically neutral. In one embodiment, G is a hydrocarbyl or
hydrocarbylene group of 1 to about 5 carbon, and in one embodiment
1 to 2 carbon atoms. In one embodiment, X.sup.y- is a nitrate ion
(y=1); in one embodiment it is an acetate ion (y=1). Suitable
examples of the amine salt include ammonium nitrate, ammonium
acetate, methylammonium nitrate, methylammonium acetate, ethylene
diamine diacetate, urea nitrate, hydroxylammonium nitrate and urea
dinitrate.
[0119] Doesn't look like this list included hydroxylammonium
nitrate--should it be included?
[0120] As an illustration, ethylene diamine diacetate can be
written in its ionic form as
[H.sub.3NCH.sub.2CH.sub.2NH.sub.3].sup.2+2CH.sub.3CO.sub.2.sup.-
[0121] In this case, in formula Z is --CH.sub.2CH.sub.2--; R is
hydrogen; y is 2; n is 2; p is 1; and X.sup.p- is
CH.sub.3CO.sub.2-- This sentence is confusing.sup.!
[0122] In one embodiment, the amine salt (G) of the present
composition functions as an emulsion stabilizer, i.e., it acts to
stabilize the present emulsified water-blended fuel composition.
Compositions with the amine salt (G) have longer stability as
emulsions than the compositions without the amine salt (G).
[0123] In one embodiment, the amine salt (G) functions as a
combustion improver. A combustion improver is characterized by its
ability to increase the mass burning rate of water-blended fuel
composition. It is known that the presence of water in fuels
reduces the power output of an internal combustion engine. The
presence of a combustion improver has the effect of improving the
power output of an engine. The improved power output of the engine
can often be seen in a plot of mass burning rate versus crank angle
(which angle corresponds to the number of degrees of revolution of
the crankshaft which is attached to the piston rod, which in turn
is connected to pistons). The mass burning rate will be higher for
a fuel with a combustion modifier than for a fuel lacking the
combustion modifier. This improved power output caused by the
presence of a combustion improver is to be distinguished from
improvement in ignition delay caused by a cetane improver. Although
some cetane improvers may function as combustion improvers, and
some combustion improvers as cetane improvers, the actual
performance characteristics or effects of combustion improvement
are clearly distinct from improvements in ignition delay. Improving
ignition delay generally relates to changing the onset of
combustion whereas improving the power output relates to improving
the peak cylinder pressure, i.e., the amplitude of the peak mass
burning rate.
[0124] When used, the amine salt (G) is present at a level of about
0.001 to about 15%, and in one embodiment from about 0.001 to about
1%, in one embodiment about 0.05 to about 5%, in one embodiment
about 0.5 to about 3%, and in one embodiment about 1 to about 10%
by weight of the emulsified water-blended fuel composition.
EXAMPLES
[0125] The following examples are intended to illustrate several
emulsifier compositions of this invention as well as means for
preparing same. It is to be understood that these examples are only
intended as illustrative of compositions and procedures and are not
intended to limit the scope of the invention. Unless indicated
otherwise, all parts are parts by weight, temperatures are in
degrees Celsius (.degree. C.), and pressures are atmospheric. When
referring to parts by volume, the relationship is as parts by
weight in grams to parts by volume in milliliters. Filtrations are
conducted using a diatomaceous earth filter aid. All analytical
values are by analysis.
[0126] Measurements of molecular weight and polydispersity are made
as described above using polystyrene standards, unless otherwise
noted. In some cases (indicated with the notation "PBU std"),
molecular weight is measured using a different model instrument
against a standard broad molecular weight distribution
polyisobutylene sample, which in turn is standardized by comparison
with a series of narrow molecular weight distribution
polyisobutylene standards. For some specimens for which the
polystyrene and PBU standards have been compared, the values for
{overscore (M)}.sub.n using the PBU standard tend to be roughly 0.7
to 0.8 times those obtained using the polystyrene standard, and the
values obtained for {overscore (M)}.sub.w/{overscore (M)}.sub.n
tend to be roughly 1.4 to 1.6 times those obtained using the
polystyrene standard.
Example 1
[0127] In a fume hood, a solution of 3.78 g (0.0394 moles) of
(NH.sub.4).sub.2CO.sub.3 in water (30 mL) is added dropwise to a
solution of 100 g (0.0315 moles, containing 9.23% water)
H.sub.3PW.sub.12O.sub.40 in water (120 mL), resulting in a
milky-white slurry. The water is evaporated by heating to isolate
the solid (NH.sub.4).sub.2.5H.sub.0.5PW.- sub.12O.sub.40 catalyst.
The catalyst is calcined under air flow in a glass tube mounted in
an oven at 450.degree. C. for 2 hours.
Example 2
[0128] In a fume hood, a 5000 mL bottom drain 4-necked round bottom
flask is fitted with a jacketed addition funnel, a cold finger, an
N.sub.2 inlet, an isobutylene inlet, a solids addition funnel
charged with 1.1 g (NH.sub.4).sub.2.5H.sub.0.5PW.sub.12O.sub.40 and
a thermometer. An N.sub.2 atmosphere is established within the
vessel whereupon 500 mL isobutylene is added from the jacketed
addition funnel. The isobutylene is allowed to reflux until the
temperature reaches -9.degree. C. To the flask is added, in
portions over the course of the reaction, 1.1 g of catalyst,
prepared as in Example 1. After stirring at -9.degree. C. for 0.3
hour, isobutylene (2500 mL) is added concurrently with catalyst.
After a total reaction time of 3.1 hours, the reactor is drained
into water to quench the reaction. The liquid is allowed to settle,
the organic layer is separated, washed with water, separated again
and dried with MgSO.sub.4. The solution is gravity filtered then
concentrated under reduced pressure from the liquid portion to
provide 287 g of an oil (16% yield) having a {overscore (M)}.sub.n
of 1444, and {overscore (M)}.sub.w/{overscore (M)}.sub.n 7.7, peak
molecular weight 10530 and vinylidene end group content=73%.
Example 3
[0129] The procedure of Example 2 is repeated except catalyst (2.4
g total) is added to the vessel in portions throughout the
reaction. After a total reaction time of 2.5 hours the vessel is
drained into water, to quench the reaction. The mixture is worked
up as in Example 2 to provide an oil [775 g; 46% yield, {overscore
(M)}.sub.n 4243, {overscore (M)}.sub.w/{overscore (M)}.sub.n 9.06
(or 3147 and 13.9, respectively, PBU std.), vinylidene end group
content 80%]. This sample is combined with 4 additional samples
prepared by the same procedure, ranging in weight from 542 to 974
g. The total blended sample is 3980 g and has {overscore (M)}.sub.n
3108, {overscore (M)}.sub.w/{overscore (M)}.sub.n 12.4 (peak
molecular weight 41597), and vinylidene end group content 80%.
Example 4
[0130] Following the procedure listed in Example 2, isobutylene
(1200 g) is reacted with 4.5 g of the supported catalyst of Example
2 over 1.75 hour before being quenched by a water/hexane mixture.
The organic layer is separated, dried over MgSO.sub.4, filtered,
and concentrated under reduced pressure [6.66 kPa (50 mm Hg) at
160.degree. C.] to provide 404 g (34% yield) of product having
{overscore (M)}.sub.n 1951, {overscore (M)}.sub.w/{overscore
(M)}.sub.n of 9.52 (or 1367 and 11.70, respectively, PBU std.) and
80% terminal vinylidene content.
Example 6
[0131] A mixture of 1464.8 g of polyisobutylene from Example 4 is
heated to 165.degree. C. and 138.7 g maleic anhydride is added over
0.1 hour. The mixture is heated to 200.degree. C. with light
subsurface N.sub.2 purge. Heating with stirring at 200.degree. C.
is continued for 24 hours. At the end of the reaction time, the
temperature is reduced to 170.degree. C. excess unreacted maleic
anhydride is removed under vacuum as the temperature is increased
to 190.degree. C., removing a total of 65.4 g distillate. The
resulting crude product is cooled and is diluted with 1473.4 g
mineral oil and filtered. The product contains 0.28 weight percent
free maleic anhydride, a Total Acid Number of 24.1 meq/g, and
contains 58.45 percent by weight non-polar species, including the
diluent oil.
Example 7
[0132] A reactor is charged with 20 g (0.0086 mol) of the product
of Example 6 and 0.76 g mineral oil. The materials are heated with
stirring under slow N.sub.2 purge to 95.degree. C. whereupon 0.13 g
ethylene glycol is added over 1 minute. The temperature is
increased to 102.degree. C. over 0.25 hour and is held at
temperature for 4.25 hours. To this material is added 0.38 g
(0.0043 mole) dimethylaminoethanol over 0.1 hour. The materials are
stirred and heated at 102.degree. C. for 2 hours, 21.26 g BP
Supreme Diesel fuel are added and stirring is continued for 0.2
hour at 75-80.degree. C. The product contains 0.10% N, and has
total acid no.=5.93 and total base number 2.72.
Example 8
[0133] A reactor is charged with 20 g of the product of Example 6
and 0.79 g mineral oil. The materials are heated with stirring with
slow N.sub.2 purge to 100.degree. C. whereupon 0.55 g
diethylethanolamine is added over 0.1 hour. The materials are
stirred and heated at 100.degree. C. for 2 hours, 21.34 g BP
Supreme Diesel fuel are added and stirring is continued for 0.1
hour at 75.degree. C. The product contains 0.12% N, and has total
acid no.=6.44 and total base number 3.56.
Example 9
[0134] Several examples of emulsified fuel compositions of this
invention are described hereinbelow. All parts are parts by weight
and unless expressly stated otherwise, are on an oil/diluent free
basis. Unless indicated otherwise, amounts of products of Examples
are on an `as prepared` basis, including solvents/diluents that may
be present. The procedure for preparing the emulsions involves
blending the aqueous component with the organic component in a high
shear mixer.
[0135] In the examples in the following table, the aqueous
component is a solution of 0.75% by weight ammonium nitrate in
water. The organic component is a mixture of fuel, emulsifier,
ester-salt cosurfactant obtained by reaction of hexadecene
substituted succinic acid with a dialkyl alkanolamine and organic
nitrate cetane improver. In each example 20 parts of the aqueous
component and 80 parts of the organic component are combined by
mixing in a Waring.RTM. Blender at low setting [.about.18,000
revolutions per minute (RPM)] for 5 minutes. The emulsion of each
example contains 76.4% of the indicated fuel, 20% of aqueous
component, 2.77% of the indicated surfactant, 0.116% cosurfactant,
and 0.476% of organic nitrate cetane improver.
1 Example Emulsifier Fuel A Product of Ex. 7 BP Supreme Diesel B
Product of Ex. 8 BP Supreme Diesel C Product of Ex. 7 BP Diesel (50
ppm S) D Product of Ex. 8 BP Diesel (50 ppm S)
[0136] Each of these blends was evaluated for emulsion stability at
ambient temperature and at 65.degree. C. After one week storage,
each emulsion showed excellent stability. At 65.degree. C., no more
than 15% of the emulsion separated into an oily or creamy-like
phase. At ambient temperature, no more than 10% separation into an
oily phase was observed. No water enriched band was visually
observed.
[0137] Each of the documents referred to above is incorporated
herein by reference. Except in the Examples, or where otherwise
explicitly indicated, all numerical quantities in this description
specifying amounts of materials, reaction conditions, molecular
weights, number of carbon atoms, and the like, are to be understood
as modified by the word "about." Unless otherwise indicated, each
chemical or composition referred to herein should be interpreted as
being a commercial grade material which may contain the isomers,
byproducts, derivatives, and other such materials which are
normally understood to be present in the commercial grade. However,
the amount of each chemical component is presented exclusive of any
solvent or diluent oil which may be customarily present in the
commercial material, unless otherwise indicated. It is to be
understood that the upper and lower amount, range, and ratio limits
set forth herein may be independently combined. As used herein, the
expression "consisting essentially of" permits the inclusion of
substances which do not materially affect the basic and novel
characteristics of the composition under consideration.
* * * * *