Note: Descriptions are shown in the official language in which they were submitted.
~S~L~4
This invention relates to clear and skable fuel
compositions Eor internal combus-tion eng:Lnes. More parti-
cularly, -this invention relates to the prepara-tion of clear
and stable liquid fuel compositions comprising (a~ a mixture
of hydrocarbons, such as gasoline (h) wa-ler, (c) a water-
soluble alcohol, such as me-thanol, and (d) a combination of
surface-active agents. These clear fuel compositions are
basically water-in-oil emulsions which have excellent
stability and viscosity over a wide range of temperatures,
including temperatures below the freezing point of water.
The liquid fuel compositions, accord:ing to the :invention,
will further mainta:in their clar:ity and :Low viscosity charae-
terist:Lcs without phase separat:i.on. 'L'hus, the compos:it:ions,
accordiny to the invent:ion, are most eEf:ic:iently uti:Lized in
operating the internal combustion engine.
An important objective of this invention is to
provide a fuel for the internal combustion engine which
results in significan-t decreases of toxic exhaust gases or
vapors without sacrificing engine performance or eEEiciency.
A second objective is to provide a Euel that is eree from
lead eompounds, sueh as lead tetraethyl, and stil:L obta:ins
an-ti-knock characteris-tics, resulting in smooth engine
performance. A third objective is to provide a fuel for the
internal combustion engine wherein the percentage of hydro-
carbons is substantially reduced, thereby better conserving
energy derived :Erom petroleum and partly replacing it with
energy having reproducible sources. A still further objec-
tive of this invention is to provide clear liquid fuel compo-
sitions that are stable and usable, bo-th under moderate and
-2- ~
extrcme ~cather conditions.
The term "water-in-oil emulsion," hcrcinafter
referrcd to as "W/O emulsion," is a general term well-known
to those skilled in emulsion technology. The term "~Y/O
emulsion," as used in the context of this invention, is
believed to best describe the physical make-up of the novel
fuel composition which we have obtained. It must be appre-
ciated that ~e have achieved, through a unique surfactant
blend, a clear and stable liquid fuel which, while an emul-
sion, e~hibits desired single-phase propelties of hydrocarbon
fuels alone. As an emulsion, however, the liquid fuel of
the invention is believed to contain the hydrocaTbon mixture
as the continuous "oil" phase and watcr and the ~ater-solubic
components as the disperscd "~ater" phase. Upon blending
the various components of the liquid fuel, including the
surfactant mixture, the resulting -fuel composition is, ~or
the purposes intended, a single-phase composition.
The oil phase of the fuel composition, according
to the invention, comprises a mixture of hydrocarbons~ such
as that derived from petroleum, an example being that having
the common name of gasoline. In the spirit o this invention,
the oil phase is not confined to a speciEic mixture of
hydrocaTbons, but embraces a broad range of mixtures of
hydrocarbons under the gene~al classification of hydrocarbon
fuels. Such hydrocarbon fuels ~ill have VaTying viscosities
and flash points, but all have the common characteristic of
combustibility providing heat and energy ~hich can be
transformcd illtO work.
The basis of thc ;nvcntion is the cIcvclopment of a
~ ~ ~S ~ ~ 4
liquid fuel containing water, which is introduced into the
fuel system in a most effective manner. It is well-known
that ~ater or steam may be injectcd, as a scparatc phase,
into internal combustion engines with the purpose of lo.~ering
the reaction temperature to retard the combustion rate and
improve the anti-knock characteristics. Such injection
methods are not only difficult to design and control, but
introduce the water as an outside phase, which not only is
ineffective in smoothly retarding the rate of combustion,
but also can quench the combustion, resulting in an incomplete
burn. ~e have now discovered that, when :he water is inti-
mately mi~ed with thc fuel, substantially complete combustion
occurs with ~ho wcltcr p~rEorming the impor~nt role of
smoothly retar~ing thc rate oE combustion, resulting in anti-
knock performance. This important discovery means thatanti-knock agents, such as lead tetraethyl, can be eliminated
in such a fuel system which not only results in cleaner
engine performance, but, even more important, results in the
elimination of lead compounds in the exhaust umes, thereby
abating pollution. ~Ye have :Eurther dlscovered that the fuel
composition, accordi~g to the invent.ion~ not only giv~s smooth
engine performance without the need for the conventional
anti-knock agents, but, more important, gives much lo~er
carbon monoxide, oxides of nitrogen, and hydrocarbon content
in the exhaust gases as compared to conventional fuels not
containing water.
We have discovcred that, ~rhen a particular combina-
tion of
surf~ce-active agellts is addccl to a hydrocarbon ~ucl, such
. ~ . 1,
s~
-
as gasoline, Yhich is tilcn combincd with a solution of a
water-solub]e alcohol and water, a hydrocarbon-rich W/O
emulsion, having the clarity and stability of a single-phase
hydrocarbon fuel, readilf forms with minimum agitation.
S Moreover, the clear fuel composition, according to the
invention, has a viscosity similar to that of a hydrocarbon
fuel itself. It has been found that the liquid Euel compo-
sition obtained is stable against phase separation by addition
of ~mounts of water or gasoline, which do not affect the
surfactant concentration. ~oreover, we have discovered that
there is no "vapor lock" when our liquid fuel is used in
conventional carburetor systems.
Accordingly, our invention is the discovery of
certain combinati~ns of surfacc-activc agents whicll will
bring both the alcollol, ~ater, and water-soluble constitu-
~nts of the fuel into complete phase with the hydrocarbon
constituent, resulting in a clear, stable liquid fuel for
the internal combustion engine. Once this clear phase is
formed, it is no longer sensitive to the addition of small
amounts of water and alcohol, or to additional amounts of
gasoline. The clear, stable Liquid fuel containing the
water, ~ater-soluble alcohol, and surface-active agents has
a low viscosity, like the hydrocarbon -fuel itself, thereby
making it easy for transport and utili~ation in conventional
carburetor systems. It is also important that the surface-
active agents themselves are organic compounds and, therefore,
combustible to carbon dioxicle and ~ater, ~hich still further
provide energy. The surface-active agents also tend to
broadcn the tcmperature-timc combustion profile because of
.
their vely hi~ points.
The surfacc-active agcnts, according to the
inventionl are virtually non-toxic in that they do not
contain harmful materials, such as sulfur, phos?horous, and
halogens. l~hile certain surface-active agents contemplated
do contain a small amount of nitrog~en, the amounts present
are insignificant, particularly when compared to the amount
of nitrogen introduced by the air required for combustion.
- The unique and novel combination of surface-active
agents of the invention comprises an an~onium long-chain
fatty acid salt, or, more preferably, a mixture of ammonium
and sodium long-chain fatty acid salts, an unsaturated acid,
and an ethylene oxide condensation product. The most
preerred cmbodimcnt inclullos a m:ixturo of ammonillm and
sod:iuln oleate, ~ree oloic acid, alld the condens.Ltion ~roduct
of an alkyl phonol with ethylene oxide. This combination of
surface-active agents, when added to the hydrocarbon fuel,
water, and alcohol constituents, provides a clear, stable
liquid fuel composition.
Although oleic acid is most preferred as the Eree
acid, other unsaturated acids, such as linoleic, may be used.
Also, saturated long-chain fatty acids, such as stearic, can
be used in combination with the unsaturated acids.
In addition to the condensation product of an alkyl
phenol with ethylene oxide, other condensation products can
be used. These products may be listed as follows~
1. Reaction products of ethylene oxide with al~yl
phenols having the formula
~*~
~O(C112CH2())
R1 - ~
where R1 is an alkyl chain having up to e:ight carbon atoms,
such as n-butyl, isooctyl, and the lihe; and n is an integer
which can vary between wide limits, such as S to 20, and
whose value determines the degree of hydrophilic character
of the surface-active agent.
2. Reaction products obtained by the condensation
with ethylene oxide of fatty acids of the formula
R2- C--(0 -CH2--CH2)nOH
Il .
ancl ~atty alcohols of the formula
R2 -t -CH2 ~CH2)nOH
where R2 is a long-chain, satur2ted or unsaturated hydro-
carbon radical, such as stearyl, cetyl, lauryl, oleyl,
linoleyl, and the like; and n is an integer which can vary
between ~ide limits, such as 5 to 20, and whose va:Lue deter-
mlnes the dcgree of hydrophilic character of the surface-active
agent.
~o 3. Reaction products of a polyol with long-chain,
saturated or unsaturated fatty acids having the formula
HOCH2- (CHOH)n- CH20C -R3
where R3 is a long-chain saturated or unsaturated hydro-
?S carbon radical~ such as stearyl, oleyl, and the li~e; and n
6 ~
is an intcgcr having a valuc usually bctwccn 1 and ~.
It ~as discovered that, when the ammonium and
sodium salts of olcic acid were used without the afore-
mentioned condensation products, we could not obtain a
stable fuel composition containing water, a water-soluble
alcohol~ and a mixture of hydrocarbons. Phase separation
occurred on cooling the fuel composition below the freezing
point of water. It was also found that, if the condensation
products were used without the ammonium and/or mixture of
ammonium and sodium salts of oleic acid, a stable, clear,
single-phase liquid containing water, a water-soluble alcohol,
and a mixture of hydrocarbons could not even be formed at
room temperature, that is, phasc scparation ;nto two phases
always occurrcd. But, wilon wo us~d a combination of the
1~ amrnonium and/or mixture oE amlllonium and sod-Lum salts of oleic
acid and the condensa-tion product of ethylene oxide and an
alkyl phenol, liquid fuel compositions, stable and clear
above and below the freezing point of water, were obtained
from the addition of this combination of surface-active
agents to the mixture of water, a water-soluble alcohol, and
the mixture of hydrocarbons.
T~e water and water-soluble aLcohol constituents
of the fuel composition, according to the invention, provide
many advantages. The invention resides in a novel combina-
tion of elements which bring the water and alcohol intointimate contact with the fuel hydrocarbons, such as gasoline,
resulting in a liquid composition which is not only clear,
but also stable, o~er tl-e operative tempcrature range of the
intcrnal combustion cnginc. Thc purpose of thc water in thc
~. . r
31!3S~6~
fuel is to provicl~ a lo-~cr tcrnpcr~ture and hroa~cr
temperature-time profi1e ~uring thc combustion of the fuel.
This results in lowcr cmissions of oxides o nitrogen and
carbon monoxide in the exhaust gases, thereby abating air
pollution. The broader temperature-time profile results in
smooth engine performance. It is believed that the water
sufficiently retards the initial phaLse of the combustion,
thereby imparting anti-knock characteristics to the fuel.
The purpose of the water-soluble alcohol, such as
methanol, is to provide anti-freeze characteristiLcs to the
fuel, thereby resulting in a liquid fuel stable below the
freezing point of water. A second purpose o the alcohol is
an energy source partly replacing the petrolcum-derived
hydrocarbons. A third purposc of the alcohol Is that it also
contributes anti-Xnock characteristics to t1lo ~ucl, resulting
in improved engine perormance.
Although we prefer methanol, the other water-soluble
alcohols, such as ethanol, isopropanol~ and mixtures of these,
can be used for this invention.
The percentage of water by weight in the composition
should range Erom about 0.1% to 10~ and preferably ranges
from 0.5% to 5%. A range o 0.1% to 20% alcohol by weight
may be used, preferably 1% to 10~ hile the amount of
surface-active agents required must depend on the amounts of
2S water and alcohol used in the fuel compositions, it is
generally preferred that the ratio of the condensation
products to the ammonium and/or mixture of ammonium and
sodium salts of the satllr~ted or unsat-lratcd long-chain fatty
acids ~c in the rangc of 1:1 to 3:1 by ~cight.
.() r
~5~
Thc prcsence of thc sodiuln salt of tile long-chain
fatty acid is not nccessary to o~tain clcar, stable liquid
fuel colnpositions in a single phase. This can be accomplished
with just the ammonium salt in combination with the afore-
S mentioned condensation products. However, the presence ofa sodium ion, in addition to an ammonium ion, in the compo-
sition is preferred because it will result in a more
desirable pH of the system, that is, a pH slightly on the
alkaline side. The advantage of this is that the sodium
salt of the long-chain fatty acid can react with acids
stronger than the fatty acid, thereby neutralizing them.
The result is not only less corrosive materials in contact
with the engine parts and exhaust systcml but, cven more
import~nt, lcss toxic materials in the oxhaust gases and
vapors. Th~ Eollowillg Eactors illustrate the importance of
using combined ammonium and sodium salts.
1. Any organic bromides or chlorides that may be
present in gasoline as additives normally will generate
hydrobromic or hydrochloric acids during combustion. Even
small amounts of these additives are corrosive and irritating.
~lowever, if our uel composition is used, the stable sodium
chloride and sodium bromide would b~ formed, which are much
less corrosive and both non;toxic and non-irritating.
2. Oxides of nitrogen in the presence of water
vapor can be partially neutralized to form the more stable
and less toxic and less irritating sodium salts.
3. Organic sulfur compounds which may be present
in gasoline gcnerate sulfur dioxide on combustion. ~ith the
high e.Yhaust tempcr.lture, and cspccially in the prcsence of
-ln- r
S16~
catalysts, such as containe~ in c~talytic devlces, oxidation
to the toxic and very irritating sulfllr trioxide, and subse-
quent entrainment of sulfuric acid in the cxhaust gases and
vapors, rcsults. The presence of a sodium ion results in
the more stable sodium sulfite compared to SO2 or H2SO3, and
there may be less tendency for the sulfur dioxide to be
oxidized to sulfur trioxide by the catalytic converter.
Even if the sulfur dioxide is oxidized to a partial extent
forming sulfur triox~de, the resulting sulfuric acid would
be neutralized, even at the high temperature, resulting in
the non-toxic and non-irritating water-soluble sodium sulfate.
The preferred molar ratio of the ammonium to the
sodium salt of the long-chaln fatty acid is in the range
rom 95:5 to 50:50. It should also be rcco~nized that the
sodium ion can b~ introducod as the soclium salt of a short-
chain fatty acid, such as sodium acetate. Since our uel
compositions contain water, the very ~ater-soluble sodium
acetate will be solubilized in the system. But, it is
easier to use the sodium salt o the long-chain fatty acids
because the resultant fue:L compositions tend to be more
stable.
An important advantage in using the combination of
surface-active agents, according to the i~vention, is that
high-shear mixing is not re~uired. The ingredients of the
fuel composition readily blend into a single phase by gentle
hand stirring. This means that such fuel compositions can
be readily prepared at the manuEacturing site or, if preferred,
prepared at the stations ~helc the gasoline can bc blcnded
~ith thc othcr constituents 1!y simply mctcrin~ thc propcr
. .
~ ~5~.~ 4
amounts of each constitucnt from storagc tanks into a common
mixing line.
The liquid fuel cornpositions of the invention can
be utilized in conventional internal combustion engines
S without any change or modification in engine design. They
can be used at low compression ratios, such as 8 to 1, or
at high compression ratios, such as 10 to 1. Engine tests
conducted with these fuel compositions show better perfor-
mance at the more efficient high compression ratios. This is
significant regarding the more efficient utilization of fuel
and better conserving o~ our energy resources. Moreover,
our fuel compositions can contain a high percentage of the
highly volatile methanol and still be utilized in conventional~
carburetor systerns without vapor lock occurring.
There are scveral ways in whLch the compon~nts can
be combined to form a suitable fuel compositlon. ~ost o
the surface-active agents can first be added to the hydro-
carbon phase and a small amount in the aqueous phase, and
then the latter added to the former. Also, the alcohol can
be added as a solution in water or it can be added separately,
either to the gasoline phase or after the water phase has
hoen dispersed. Ihe preferred method is to blend three
solutions simultaneously, narnely,
(1) lead-free gasoline or similar hydrocarbon fuel;
(2) solution of surface-active agents; and
(3) water or a solution of a water-soluble alcohol
in water.
The follo-~ing e.~amples are provided simply to
illustrate the embo~imcnts of our invention and are not
I ~ ...... . .
51~
int~n~cd to lilnit it in al~y ~ay.
Examplc 1
A stock solution w~s prepared by mixing l,000 ml.
of NP-14, l,000 ml. of NY-27, 900 ml. of oleic acid, and
100 ml. of concentrated ammonium hydroxide solution. The
ammonium hydroxide solution contained 29.9% N~13 and had a
density of 0.89 gm/ml. The NP-14 and the NP-27 are polyoxy-
ethylene alkyl phenol-type surface-active agents obtained
from Union Carbide Corporation. They were found to have
respective densities of 1.03 and 1.06 gm/ml.
The stock solution, therefore, contained the
following:
1,030 granls NP-l4
1,060 grallls NP-27
468 gr;lms amlllolliunl oloake
363 grams free oleic acid
62 ~rams water
2.g83 grams total
This solution was viscous, colorless, and clear at room
temperature. It had a density of 0.98 gm/ml.
1`he stock solution, labeled E-019, was u-,ed to
preparo the ~ollo~ing liquid ~u~l ~ormula~ions:
Unleaded
E-019 l~ater ~lethanol gasoline
ml ml ml ml
~ormulation ~ 25 5 15 155
~ormulation B 25 lO lO 155
In pre~ ing cach formulation, the ~ater and
mcthallo1 ~Jere first acl~cd to F,-019, resulting in a clear
I;
~)8S16~
solution. Unle~cled gasoli1le was added to this clear solution,
resultin~ in a clear, ~ing~e phase liquid.
Both of the li~uid fuel compositions werc refrig-
erated at -20 C. overnight. They were then examined and
S found to still be clear and in a single phase. The samples
were removed, brought to room temperature, and then immersed
in warm water. They still remained clear and in a single
phase. In other words, there was no phase separation or
reduction in clarity by subjecting the samples to extreme
temperature differences.
The calculated weight percentages of ~he
constituents of the above formulations are as follows:
~ormulation
A B
~ . .
lS Non-leacled gasoline, % 73.50 73.00
NP-l~, % 5.~3 5.39
NP-27, % 5.59 5.55
Ammonium oleate, % 2.46 2.45
Free oleic acid, % 1.91 l.9o
~ater, ~ 3.54 6.70
Methanol, % 7.57 5.01
Exa~ 2
Formulation A of Example 1 was kept the same
cxcopt that the 15 ml. oE mcthanol were replaced by lS ml. of
ethanol. There resulted a clear, single-phase liquid. lhis
liquid was also refrigerated at -Z0 C. overnig}lt. It was
examined and found to still be clear. The clarity and single
phase remained the same when the liquid fuel was warmcd.
J
~)8S1~9L
~ ample 3
,
Formulation ~ of Example 1 was kept th~ same
except that the 15 ml. of methanol ~ere replaced by 15 ml.
of isopropanol. There ~esulted a clear, single-phase liquid.
It also maintained the same clarity and single phase after
subjection to -20 C. overnight and then followed by warming.
Example 4
A solution was prepared from 90 ml. of oleic acid,
lS ml. of concentrated ammonium hydroxide (29.9% NH3 and
density of 0.89 gm/ml.), and 100 ml. of Span 80 (an ester of
a polyol and long-chain fakty acicl~.
Ten ml. of water and 10 ml. oE methanol were a1cled
to 25 ml. oE this solut;.oll. 'rhere resul-ted a c:Le,lr soLution
to which were addod 155 ml. oE unleaded gasoline. A clear,
single-phase liquid ~as obtained having a low viscosity,
such as those fuel compositions described in Examples 1 to 3.
It also maintained the same clarity and single phase after
subjection to -20 C. overnight and then follo~ed by warming.
Exam~ 5
One gram o~ sodium h~Jclrox:lde in 5 ml. oE l~ater was
added to 100 ml. of the stock solution labeled E-019,
described in Example 1. This ~as su-fficient socLium hydroxide
to neutralize about 59% of the free oleic acid so that the
molar percent ratio of ammonium oleate to sodium oleate in
~5 the resulting solution ~as about 67 to 33. ~hen the sodium
oleate first formed, it precipitatcd out hut thell ~uickly
dissolved, resulting in a clear solution.
~'
~s/9
~S~
Tcn ml. of methanol wcre added to 8Q ml. of low-lead
gasolinc. Phase separation occurred. Then, 10 ml. of the
above solution wcre added, and the contents lightly stirred.
There resulted a single-phase, clear, low viscosity liquid.
S This liquid was placed in ~ freezer at -Z0 C. overnight.
The fuel composition was still clear and in a single phase
at this low temperature.
Example 6
Performance tests were conducted at a commercial
laboratory which was fully equipped to follow the 1973 Federal
Test Procedure for constant volume sampling of exhaust gases.
The test vehicle was a 1973 Plymouth E~ury III ~A
Chryslcr Corporation product).
Vchiclc specifications were as follows:
Displacement 360 cubic inches
A/F ratio 15.5:1
Compression ratio 8.5:1
The vehicle wax equipped with government specified
e~ission control devices J i.e., exhaust gas recirculation
20 and positive crankcase ventilation.
The base fuel was a 91 octane Iow-lead gasoline
blend. The stock solution, E-019, of Example 1 was used to
prepare two clear liquid fuel compositions comprising the
following weight percentages:
-l6- r
~ ~5 ~6 ~
lucl Coml)osition ~ucl Composition
B
Percent water 2.5 0.5
Percent mcthanolZ.5 7.5
Percent E-019 6.9 10.5
Percent base fuel 88.1 8i.5
The base fuel and fuel composition A were tested
in the above engine. The exhaust emissions in grams/mile
' were as follows:
Exhaust Emissions In Gr ms/~lile
Base Fuel Fuel Com~~Ltion A
....
~IC 3.7 3.2
C0 36.0 18.7
Nx ~.7 '~.1
Total 44.4 25.0
These data show a 44% reduction in total exhaust
emissions using fuel composition A compared to the base fuel.
Furthermore, the research octane number increasecl from 93.2
to 95.2 in going from the base fuel to Euel composition A.
The base Euel was then compared with fuel
composition B7 giving the follol~ing test rcsults:
Exhaust Emissions In Grams/Mile
Base Fuel Fuel Composition B
HC 2.73 2.70
C0 50.46 26.26
Nx 3-l0 2.S3
Total 56.29 31.79
These dat~l also sllow ahout a 4~ rcduction in
total exhaust emissions using fucl comyosition B compared to
the ~ase fuel. Performance through cold starts and accel-
erations ~as fourld cqually good for -fwel composition B
compared to the base fuel.
Example 7
The following solutions or mixtures were blended:
(a) 160 ml. of lead-free gasoline;
tb) a mixture of 5 ml. of NP-14 and 5 ml. of
NP-27 (non-ionic surEactants of the polyoxyethylene alkyl
phenol-type obtained Erom Union Carbide Corporation), and
5 ml. of a solution oE ammollium oleate in ole:Lc acid in
which the conccntration of amrnon:lum oleate wa!; about 50~;
and
lS (c) a solution of 5 ml. of water and 5 ml. of
ethyl alcohol.
l~hen (b) was added to (a), a clear solution
Tesulted. ~hen (c) was added and the contents mixed gently,
a W/O emulsion resulted. When a beam of light ~as passed
through the W/O emulsion fuel held in a dark room~ we
observed the Brownian ~lotion o~ colloidal particles within
the shaft of light, confirming the Tyndall effect of the
liquid-to-liquid colloidal emulsion.
The composition was placed in a refrigerator and
cooled to about -12 F. The cold emulsion remained clear
and still exhibited the characteristic Tyndall e~fect.
~S~
~x~lllpl~ 8
Thc same formulation as in Example 7 except that
the ethanol was replaced with methanol. A stable composi-
tion resulted as in Example 7.
Example 9
The same formulation as i.n Example 7 except that
the ethanol was replaced with isopropanol. A stable
composition resulted as in Example 7.
~ Yhile certain representative embodiments and
details have been shown for the purpose of illustrating the
invention, it will be apparent to those skill.cd in ~he art
that various changes and moclificatiorls Inay be made therein
without dcparting ~rom the scope o~ ~he invcntiorl as dcf:ined
by the appended claims.
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