A multipurpose fuel composition is disclosed which contains a petroleum derived jet fuel component and a renewable jet fuel component, wherein the multipurpose fuel composition has a freezing point of −40° C. or below, and an exemplary cetane number more than 40, preferably more than 45, more preferably more than 50.

A multipurpose fuel composition is disclosed which contains a petroleum derived jet fuel component and a renewable jet fuel component, wherein the multipurpose fuel composition has a freezing point of −40° C. or below, and an exemplary cetane number more than 40, preferably more than 45, more preferably more than 50.

A fuel for an internal combustion engine includes a fatty alkyl ether having a formula corresponding to formula (II): ##STR00001##
wherein x is 1-8, and y is 0 to 3; and the alkyl is an alkyl group having a number of carbon atoms that is less than the number of carbon atoms in the alkyl chain on the opposite side of the oxygen atom. The fatty alky ether can be used as a neat fuel or blend with biodiesel, diesel, ethanol or other fuels. The fatty alkyl ethers are improved in cetane number and cold flow properties over a biodiesel with fatty acid methyl acid methyl ester compounds. This is particularly valuable for compression ignition engines. A method of combustion in several types of engines is also disclosed.

The present invention relates to a nitrogen-containing terpolymer biodiesel solidification point depressant, and a preparation method and application thereof. The preparation method includes the following steps: 1) respectively preparing methylacrylic acid high carbon ester and N-hexadecyl methacrylamide; 2) adding the methylacrylic acid high carbon ester, the N-hexadecyl methacrylamide, and vinyl acetate to a solvent, and adding an initiator for polymerization to yield a methylacrylic acid high carbon ester-N-hexadecyl methacrylamide-vinyl acetate terpolymer, i.e., a nitrogen-containing terpolymer biodiesel solidification point depressant. Compared with the prior art, the nitrogen-containing terpolymer biodiesel solidification point depressant of the present invention solves the problem of poor compatibility of single methylacrylic acid depressants, N-hexadecyl methacrylamide and vinyl acetate are introduced to extend the composition of the depressant and improve a solidification point depression effect, the preparation process of the depressant is simple, and the experimental operation is convenient.

A winterized paraffin inhibitor, which is capable of being used for preventing the deposition of paraffins in hydrocarbon streams and capable of withstanding freezing or crystallization at freezing or sub-freezing temperatures, may be formed by adding an oxyalkylated branched aliphatic compound having 12 or more carbons to a high molecular weight aliphatic polymer paraffin inhibitor, the oxyalkylated branched aliphatic compound having 12 or more carbons being produced by the oxyalkylation of the branched aliphatic compound having 12 or more carbon atoms in which the branched aliphatic compound having 12 or more carbon atoms is grafted with a polyether via a ring-opening reaction, wherein the polyether is a polymer of ethylene oxide, propylene oxide, butylene oxide, and combinations thereof.

The subject matter of the present invention is the use, for improving the cold-resistance properties of a fuel or combustible composition, of one or more copolymers comprising:—at least one unit of formula (I): in which R.sub.1 is a hydrogen atom or a methyl group; X is —O—CO—, or —CO—O— or —NH—OO— or —CO—NH—; R.sub.2 is a C.sub.6 to C.sub.24 alkyl group; and at least one unit of formula (II): in which R is a substituted or unsubstituted imidazole ring. The invention also relates to compositions of additives containing such a polymer, and also fuel or combustible compositions to which such polymers have been added, preferably in combination with a cold flow improver (CFI) additive or a paraffin anti-settling additive (WASA).

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The formation in a liquid hydrocarbon fuel of ice particles having a weight average particle size greater than 1 μm when said liquid hydrocarbon fuel is cooled to temperatures in the range of from 0 to −50° C. can be reduced or eliminated by use of at least one surfactant that is capable of dispersing water in said liquid hydrocarbon fuel to provide a stable clear water-in-oil microemulsion wherein the droplet size of the dispersed water phase is no greater than 0.25 μm.

The formation in a liquid hydrocarbon fuel of ice particles having a weight average particle size greater than 1 μm when said liquid hydrocarbon fuel is cooled to temperatures in the range of from 0 to −50° C. can be reduced or eliminated by use of at least one surfactant that is capable of dispersing water in said liquid hydrocarbon fuel to provide a stable clear water-in-oil microemulsion wherein the droplet size of the dispersed water phase is no greater than 0.25 μm.

The present invention relates to a composition of additives, comprising: at least one copolymer having at least one motif of formula (I) and at least one motif of formula (II); at least one cold-flow improver selected from the copolymers of ethylene and unsaturated ester(s); and at least one anti-settling and/or paraffin dispersant additive.

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Reversion problems with heavy oils, such as heavy fuel oils, are mitigated by introducing an effective amount of an additive that contains both a phase change material and a pour point depressant, even synergistically mitigated.