There is provided a method of providing an improved biofuel, by the presence of an additive which is the reaction product of (i) a compound containing the segment —NR.sup.1R.sup.2 where R.sup.1 represents a group containing from 4 to 44 carbon atoms and R.sup.2 represents a hydrogen atom or a group R.sup.1 (for example di-hydrogenated tallow amine) and (ii) a carboxylic acid having from 1 to 4 carboxylic acid groups or an acid anhydride or acid chloride thereof (for example phthalic acid or phthalic anhydride). The additives described combat problems arising from precipitation at temperatures above the cloud point.

Described herein are associative polymers capable of controlling one or more physical and/or chemical properties of non-polar compositions and related compositions, methods and systems.

A drag reducing agent has a core comprising a polyolefin; and a temporary container encapsulating the core. The temporary container contains a container material, which includes an ethylene vinyl acetate copolymer, an ethylene vinyl alcohol copolymer, a polyvinylpyrrolidone, an ethylene vinylpyrrolidone copolymer, a vinylpyrrolidone vinyl acetate copolymer, a polyvinyl acetate, a polyvinyl alcohol, a polyethylene oxide, a polyethylene glycol, polyvinylidene chloride, a polysaccharide or its derivative, or a combination comprising at least one of the foregoing. A largest dimension of the drag reducing agent is greater than about 1,000 microns.

This invention relates to a fuel oil composition, containing a low-sulfur marine diesel having a sulfur content of less than 1 wt. % and (A) at least one ethylene copolymer and (B) at least one comb polymer.

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.

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 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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A composition is provided that includes about 1 weight % to about 49 weight % of a copolymer including ethylene and vinyl acetate; about 1 weight % to about 49 weight % of an acrylate-containing copolymer; and about 2 weight % to about 98 weight % of a solvent. The composition can be used to decrease the pour point of a hydrocarbon, such as crude oil.

The present invention relates to a low-temperature additive for fuel oils having a sulfur content of less than 50 ppm, comprising i) at least one oil-soluble amide-ammonium salt of a polycarboxylic acid with a mono- and/or dialkylamine (A) and ii) 5-100% by weight, based on the amount of amide-ammonium salt (A), of an oil-soluble amine (B), and iii) 0.1 to 10 parts by weight, based on the amount of amide-ammonium salt (A), of a resin formed from at least one aromatic compound bearing an alkyl radical and an aldehyde and/or ketone (D).

Described herein are associative polymers capable of controlling a physical and/or chemical property of non-polar compositions that can be used when the non-polar composition is in a flow, and related compositions, methods and systems. Associative polymers herein described have a non-polar backbone with a longest span having a molecular weight that remains substantially unchanged under the flow conditions and functional groups presented at ends of the non-polar backbone, with a number of the functional groups presented at the ends of the non-polar backbone formed by associative functional groups capable of undergoing an associative interaction with another associative functional group with an association constant (k) such that the strength of each associative interaction is less than the strength of a covalent bond between atoms and in particular less than the strength of a covalent bond between backbone atoms.