There is disclosed an antifoam component which includes at least one acrylamide polymer for use in a diesel fuel. Acrylamide polymers prepared by polymerizing a (meth)acrylamide monomer to yield a homopolymer or, alternatively, the acrylamide polymer may be prepared by polymerizing a (meth)acrylamide monomer and a (meth)acrylate monomer to yield a heteropolymer.

A method making fuel oil from refining residuals. Refining residuals are mixed with a diluent and an additive. Preferred diluents include diesel and reformed naphtha and combinations thereof. The additive is believed to be a cross-linked cyclic anhydride copolymer having an intrinsic viscosity (limiting viscosity, ) of between about 0.10 and 3.0 deciliters per gram and an average molecular weight between about 3,000 and 3,000,000. The additive includes excess aromatic hydrocarbons and a surfactant. In the preferred embodiment, the diluent and the residuals are mixed together in a ratio of about 3:1, by weight. The additive is introduced to this mixture in the amount of about 0.10 to 0.25 percent by weight. The components are thoroughly combined to yield a fuel oil having a viscosity that is about 25 to as much as about 70 percent lower than the viscosity of the same residual/diluent mixture lacking the additive.

The invention relates to a composition of additives for fuel, comprising: (a) one or more copolymer(s) comprising the following units of formulae (I) and units of formula (IIa): R representing a hydrocarbon-based chain substituted with at least one amino group comprising at least one quaternary ammonium or iminium function, and (b) one or more copolymer(s) comprising units of formulae (I) and units of formula (IIb): R representing a hydrocarbon-based chain substituted with at least one amino group comprising at least one primary, secondary or tertiary amine function or imine function. The invention also relates to the use of such a composition as a detergent additive and/or demulsifying additive in a liquid fuel for an internal combustion engine.

##STR00001##

The present invention relates to a copolymer obtainable by copolymerization of

(A) at least one unsaturated dicarboxylic acid or derivatives thereof,
(B) at least one -olefin having from at least 6 up to and including 20 carbon atoms,
(C) optionally at least one C.sub.3- to C.sub.20-alkyl ester of acrylic acid or methacrylic acid or a mixture of such alkyl esters and
(D) optionally one or more further copolymerizable monomers other than monomers (A), (B) and (C),
with a molar incorporation ratio of (A):(B):(C):(D) of 1:0.5 to 2.0:0 to less than 0.5:0 to 0.1
followed by the reaction with at least one dialkylamine (E), where the two alkyl radicals in the at least one dialkylamine (E) are independently alkyl radicals having at least 17 up to 30 carbon atoms.

A copolymer obtained by copolymerization of at least: an apolar monomer (m.sub.a) with the following formula (I), where u=0 or I, w=0 or I, E=-0- or NH(Z), or OCO, or NHCO or CONH, wherein Z is H or an alkyl group, and G is a group selected among an alkyl, an aromatic ring and an arylalkyl; and a polar monomer (m.sub.b) selected among those of the following formula (II), wherein t=0 or I, Q is selected among the oxygen atom and the NR group, wherein R is selected among a hydrogen atom and hydrocarbon chains, and R is a hydrocarbon chain substituted by at least one quaternary ammonium group and optionally one or more hydroxyl groups. The invention also relates to the use of such a copolymer as a detergent additive in a liquid fuel of an internal combustion engine.

A block copolymer including: at least one block A of following formula (I): ##STR00001##
in which p is an integer ranging from 2 to 100, R1 is selected from hydrogen and the methyl group, R2 is chosen from C1 to C34 hydrocarbon-based chains, at least one block B of following formula (II): ##STR00002##
in which n is an integer ranging from 2 to 40, R1 is chosen from hydrogen and the methyl group, Z is chosen from the oxygen atom and the group NR with R being chosen from a hydrogen atom and C1 to C12 hydrocarbon-based chains, G is a C1 to C34 hydrocarbon-based chain substituted by at least one quaternary ammonium group and optionally one or more hydroxyl groups. Also, the use of such a block copolymer as detergent additive in an internal combustion engine liquid fuel.

Disclosed are paraffin inhibitors, paraffin suppressant compositions, and methods of making and using them. The paraffin inhibitors comprise polymers of a maleic moiety polymerized with at least two olefins having hydrocarbon chains of a different length from each other. When added to hydrocarbon media such as crude oils to form crude oil compositions, the paraffin inhibitors inhibit the precipitation of paraffin waxes in the crude oil compositions and exhibit reduced precipitation, gelling, and/or crystallization from the hydrocarbon media when the media are subjected to sustained low temperatures.

This disclosure relates to winterized pour point depressant compositions for petroleum fluids. Such compositions exhibit stability and are flowable at temperatures down to as low as 47 C., without the need for further dilution.

A composition of additives for fuel including: one or more copolymer(s) including:at least one unit of the following formula (I): wherein R1 is selected from hydrogen and methyl group, R2 is selected from C1 to C34 hydrocarbon-based chains, an aromatic ring, an aralkyl containing at least one aromatic ring and at least one C1-C34 alkyl group, andat least one unit of following formula (II): wherein R1 is selected from hydrogen and methyl group, Z is selected from the oxygen atom and NR group with R being selected from a hydrogen atom and C1 to C12 hydrocarbon-based chains, G includes a C1 to C34 hydrocarbon-based chain substituted with at least one quaternary ammonium group and optionally one or more hydroxyl groups, group G also possibly containing one or more nitrogen and/or oxygen atoms and/or carbonyl groups 25 at least one compound selected from succinimides substituted with a hydrocarbon-based chain.

Disclosed herein are paraffin suppressant compositions, and methods of making and using them. The compositions comprise a paraffin inhibitor, a hydrocarbon-soluble hydrotrope equivalent, and optionally one or more additional paraffin dispersants. When added to hydrocarbon media such as crude oils to form crude oil compositions, the suppressant compositions inhibit the precipitation of paraffin waxes in the crude oil compositions. The suppressant compositions, added to hydrocarbon media such as hydrocarbon solvents or crude oils, exhibit reduced precipitation, gelling, and/or crystallization of paraffin inhibitor from the hydrocarbon media, when the media are subjected to sustained temperatures between 4 C. and 60 C.