Fuel/water emulsions

Details Fuel/water emulsions Fuel/water emulsions

1998-01-15

2001-08-28

Medley, Margaret (Department: 1714)

Fuel and related compositions

Liquid fuels

Emulsion fuel

C044S301000

Reexamination Certificate

active

06280486

ABSTRACT:

DESCRIPTION
Fuel/water Emulsions
It is already known in the field of large diesel engines, e.g. as used in shipbuilding, or in that of high-performance internal combustion engines, e.g. for racing cars, to inject water in a controlled manner into the combustion chamber. This achieves improved efficiency and increased knock resistance. The essential advantage of such a water injection is that the discharge of nitrogen oxides is reduced in this manner.
The use of water-containing fuels is disclosed, for example, in GB-A-0669037, GB-A-0205582, EP-A-0 095 823 and WO-88/04311. Said documents teach the use of mixtures of a hydrocarbon, an alcohol and water as an operating substance for internal combustion engines.
EP-A-0 431 357 discloses a method of operating internal combustion engines using water-containing fuels, a catalyst being used in the combustion chamber.
EP-A-0 372 353 discloses the preparation of a fuel/water mixture by means of an electromagnetically operating device.
The object of the present invention is to avoid separate injection of water and the use of catalysts and to develop alcohol-free emulsions which simultaneously contain the fuel and the water in uniform form. This object was achieved by using a special emulsifier and a stabilizer.
The present invention relates to fuel/water emulsions essentially comprising 60 to 80% by weight of a fuel, 0.5 to 5% by weight of one or more water-soluble and gasoline-insoluble emulsifiers of the formulae
(A) R—O—(CH
2
CH
2
O)
x
—H
where R is alkyl or alkenyl having in each case 8 to 18 carbon atoms or C
9
-C
14
-alkylphenyl and x is a number from 8 to 30, and/or
(B) ethylene oxide/propylene oxide block polymers in which the proportion of the ethylene oxide units is between 40 and 80% by weight of the molecular mass, and/or
where x is a number between 10 and 30, and 1 to 10% by weight of a water-soluble and gasoline-insoluble poly(alkylene glycol) as stabilizer, also water and, if appropriate, other additives to 100% by weight.
Preferably, 0.5 to 1% by weight, in particular 0.65 to 0.75% by weight, of emulsifier is used. In the case of the compounds mentioned under A), R is preferably alkyl or alkenyl having 12 to 16 carbon atoms or C
9
-alkylphenyl. x is preferably a number between 9 and 13. In the case of the compounds mentioned under C), x is preferably a number between 9 and 13. The emulsifier is generally commercial ethoxylation products: (A) are ethoxylated fatty alcohols, preferably ethoxylated alkylphenols (®Arkopal, manufactured by Hoechst AG) and (B) are EO/PO-copolymers of the formula
HO—(C
2
H
4
O)
a
—(C
3
H
6
O)
b
—(C
2
H
4
O)
c
—H.
In these block polymers, the indices a, b and c are such that the proportion by weight of EO is 40 to 80%. The numerical values of a, b and c therefore depend on the molecular mass of the block polymers, which is preferably between 2000 and 10,000 units. These copolymers of ethylene oxide (EO) and propylene oxide (PO) are commercially available under the name ®Genapol PF (Hoechst AG). The butylphenol ethoxylates described under C) are marketed under the name ®Sapogenat T (Hoechst AG). C
4
H
9
is here an n-, iso- or tert-butyl radical. Emulsifiers preferably used are the ethoxylated alkylphenols, of which the ethoxylated nonylphenols are in turn preferred.
The poly(alkylene glycol) used as stabilizer is preferably added in amounts of 1.5 to 5, in particular 2.5 to 3.5, % by weight. Preferred poly(alkylene glycols) are those which contain both ethylene oxide groups and propylene oxide groups, as, for example, the polyglycol B11 types from Hoechst AG. Furthermore, preference is given to using poly(alkylene glycols) which have molecular masses between 1000 and 10,000 units.
The emulsions according to the invention can, in addition, further contain, as further additive, 0.5 to 8, preferably 1.5 to 2.5, % by weight of hydrogen peroxide as biostatic agent. Hydrogen peroxide has the advantage that it supplies additional oxygen for the combustion of the fuel, but other bactericidal, algicidal and fungicidal agents which burn without leaving a residue can also be used. All amounts given in % by weight relate to the entire emulsion.
The fuel used is preferably gasoline for internal combustion engines (for example regular-grade or premium-grade), but other types of fuel can also be used such as diesel oil, naphtha or kerosine. Preference is given to fuel/water emulsions which contain 70-75% by weight of regular-grade or premium-grade gasoline.
The fuel/water emulsions according to the invention can be prepared in various ways. One possibility is to dissolve emulsifier and poly(alkylene glycol) in warm water and to stir this solution into the fuel. The mixture is stirred for a short period and the agitator unit is then switched off, whereupon the mixture separates into two phases. It is then stirred again until the emulsion is homogeneous and sufficiently mobile. It is essential in this process variant that stirring ceases intermittently and the emulsion is allowed to stand briefly.
In the second process variant, emulsifier and poly(alkylene glycol) are likewise dissolved to give a clear solution in water. The fuel is then stirred into this solution and stirring is continued until the emulsion is homogeneous and mobile. The water required to prepare these emulsions is preferably demineralized, in order that no solid residues form when these emulsions are burnt. Suitable equipment for preparing the emulsions according to the invention is all equipment known for this purpose to those skilled in the art, for example high-shear dispersion units (Ultraturrax), ultrasonic dispersers or dispersion disks of the Cowls-mixer type or a Caddy Mill.
The fuel/water emulsions according to the invention are suitable for operating internal combustion engines, in particular direct-injection internal combustion engines.


REFERENCES:
patent: 2920948 (1960-01-01), Weeks
patent: 3458294 (1969-07-01), Nixon et al.
patent: 3490237 (1970-01-01), Lissant
patent: 3519006 (1970-07-01), Simon et al.
patent: 4246919 (1981-01-01), McClaflin
patent: 4294586 (1981-10-01), Cox, Jr.
patent: 4295859 (1981-10-01), Boehmke et al.
patent: 4382802 (1983-05-01), Blinke
patent: 4395266 (1983-07-01), Han
patent: 4570656 (1986-02-01), Matlach et al.
patent: 5000757 (1991-03-01), Puttock et al.
patent: 0095823 (1983-12-01), None
patent: 0327353 (1990-06-01), None
patent: 0431357 (1991-06-01), None
patent: 582762 (1994-02-01), None
patent: 205582 (1923-10-01), None
patent: 669037 (1952-03-01), None
patent: WO85/04183 (1985-09-01), None
patent: WO 8804311 (1988-06-01), None
Foreign Search Report Unknown Date.
Derwent Abstract-WO 85/04183 Unknown Date.

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