Ionic liquid containing compositions may be used in the production, recovery and refining of oil and gas. In addition, they may be used to treat wastewater and/or to inhibit and/or prevent fouling of contaminants onto surfaces.

An olefin-carboxylic acid copolymer, containing at least one free carboxylic acid side group, or a nitrogen compound quaternized with epoxide in the presence of an olefin-carboxylic acid copolymer, containing at least one free carboxylic acid side group, can be used as a fuel additive or lubricant additive. Processes can be used for preparing additives of this kind and fuels and lubricants additized therewith, such as a detergent additive. These additives, fuels, and lubricants can be used for reduction or prevention of deposits in injection systems of direct injection diesel engines, especially in common rail injection systems: for reduction of fuel consumption of direct injection diesel engines, especially of diesel engines with common rail injection systems; and for minimization of power loss in direct injection diesel engines, especially in diesel engines with common rail injection systems. The additives can also be used for gasoline fuels, especially for operation of DISI engines.

An olefin-carboxylic acid copolymer, containing at least one free carboxylic acid side group, or a nitrogen compound quaternized with epoxide in the presence of an olefin-carboxylic acid copolymer, containing at least one free carboxylic acid side group, can be used as a fuel additive or lubricant additive. Processes can be used for preparing additives of this kind and fuels and lubricants additized therewith, such as a detergent additive. These additives, fuels, and lubricants can be used for reduction or prevention of deposits in injection systems of direct injection diesel engines, especially in common rail injection systems; for reduction of fuel consumption of direct injection diesel engines, especially of diesel engines with common rail injection systems; and for minimization of power loss in direct injection diesel engines, especially in diesel engines with common rail injection systems. The additives can also be used for gasoline fuels, especially for operation of DISI engines.

A fuel additive composition includes: (a) one or more copolymers including:

at least one unit of formula (I) below:

##STR00001##

with u=0 or 1, E=—O— or —N(Z)—, or —O—CO—, or —CO—O— or —NH—CO— or —CO—NH—, with Z representing H or a C.sub.1-C.sub.6 alkyl group, G represents a group chosen from a C.sub.1-C.sub.34 alkyl, an aromatic nucleus, an aralkyl including at least one aromatic nucleus and at least one C.sub.1-C.sub.34 alkyl group, and —at least one unit of formula (II) below:

##STR00002##

in which R.sub.1″ is chosen from a hydrogen atom and a methyl group, Q is chosen from an oxygen atom and a group —NR′— with R′ being chosen from a hydrogen atom and C.sub.1 to C.sub.12 hydrocarbon-based chains, R comprises a C.sub.1 to C.sub.34 hydrocarbon-based chain substituted with at least one quaternary ammonium group.

A method minimizes power loss in a direct injection diesel engine by adding a copolymer to a diesel fuel composition. The copolymer contains, in a copolymerized form, (A) maleic anhydride, (B) an α-olefin having from 12 to 30 carbon atoms, (C) optionally an additional aliphatic or cycloaliphatic olefin which has at least 4 carbon atoms and is different from monomer (B), and (D) optionally an additional copolymerizable monomer other than monomers (A), (B) and (C). Monomer (D) can be a vinyl ester, a vinyl ether, a (meth)acrylic ester of an alcohol having at least 5 carbon atoms, an allyl alcohol or an ester thereof, a N-vinyl compound, an ethylenically unsaturated aromatic, an α,β-ethylenically unsaturated nitrile, a (meth)acrylamide, or an allylamine. Anhydride functionalities present in the copolymer are partly reacted with at least one compound (E) comprising an alcohol group and/or an amino group, and the anhydride functionalities present are hydrolyzed.

The present invention concerns the use, for lowering the cold filter plugging point of a fuel composition, of one or more crosslinked polymers comprising at least one unit of the following formula (I): in which R.sub.1 represents a hydrogen atom or a methyl group; E represents —O—CO—, or —CO—O— or —NH—CO— or —CO—NH—; and G represents a C.sub.1 to C.sub.34 alkyl group; said copolymer having a crosslinking rate of between 0.5 mol % and 30 mol %. The invention also concerns additive compositions containing such a polymer, and fuel compositions with such polymers as additives, in combination with a cold flow improver (CFI) chosen from the copolymers and terpolymers of ethylene and vinyl and/or acrylic ester(s).

##STR00001##

Ethylene-C.sub.3-C.sub.10 alpha olefin copolymers, dispersants and lubricating oils/fuel compositions incorporating dispersants, and related methods are generally described herein. The copolymer may comprise ethylene-derived units and C.sub.3-C.sub.10 alpha-olefin-derived units. The C.sub.3-C.sub.10 alpha-olefin-derived units may have a carbon number from three to ten. For example, the C.sub.3-C.sub.10 alpha-olefin-derived units may be propylene-derived units. The dispersants may be made from copolymers having low metal and/or fluorine contents.

A method for minimizing power loss, reducing a fuel consumption and/or for reducing and/or avoiding deposits in a fuel system in the direct injection diesel engines. The method contains adding a copolymer to a fuel composition, wherein the copolymer contains, in a copolymerized form: (A) an ethylenically unsaturated mono- or dicarboxylic acid or a derivative thereof, (B) an -olefin having from 12 to 30 carbon atoms, (C) optionally an additional aliphatic or cycloaliphatic olefin which has at least 4 carbon atoms and is different from monomer (B) and (D) optionally an additional copolymerizable monomers other than monomers (A), (B) and (C), anhydride or carboxylic acid functionalities present in the copolymer are partly reacted with at least one compound (E) comprising an alcohol group and/or an amino group, and the anhydride functionalities present in the copolymer are hydrolysed and/or carboxylic ester functionalities present in the copolymer are partly hydrolyzed.

Disclosed are cloud point depressants and methods of making and using them. The disclosed cloud point depressants comprise copolymers of a maleic moiety polymerized with alpha olefins and then contacted with an aliphatic tertiary amine to provide a cloud depressant reaction product. When the disclosed reactions products are added to middle distillate fuels or blends of middle distillate fuels with biodiesel, the cloud point depressants inhibit the precipitation of waxes and/or biowaxes in the fuels and the fuels exhibit reduced precipitation, gelling, and/or crystallization when subjected to low or cold temperatures.

Disclosed are cloud point depressants and methods of making and using them. The disclosed cloud point depressants comprise copolymers of a maleic moiety polymerized with alpha olefins and then contacted with an aliphatic tertiary amine to provide a cloud depressant reaction product. When the disclosed reactions products are added to middle distillate fuels or blends of middle distillate fuels with biodiesel, the cloud point depressants inhibit the precipitation of waxes and/or biowaxes in the fuels and the fuels exhibit reduced precipitation, gelling, and/or crystallization when subjected to low or cold temperatures.