A fuel composition comprising as an additive the reaction product of a polycarboxylic acid having no more than 5 carbon atoms per carboxylic acid group, or an anhydride thereof and an alcohol having at least 5 carbon atoms.

This invention provides a wax inhibitor composition comprising A) the reaction product obtainable by reaction of i) a carboxylic acid containing an optionally substituted cycloaliphatic hydrocarbyl residue with ii) an alkylene polyamine, B) a polymeric wax inhibitor, and C) an organic solvent.

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.

The present invention provides a fuel oil composition, including: a fuel oil base oil having a sulfur element content of from 0.01 mass % to 0.50 mass %; and a calcium salicylate having a total base number of from 100 mgKOH/g to 1,200 mgKOH/g.

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.

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).

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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.

The present invention relates to a composition of additives comprising: at least one first compound selected from: (i) copolymers of ethylene and vinyl acetate having a molar mass Mn included in the range ranging from 10,000 to 60,000 g.Math.mol1, optionally grafted by at least one alkyl (meth)acrylate group, the alkyl chain of which is saturated and contains from 12 to 30 carbon atoms; and (ii) polymers comprising at least 90 mol % of units derived from alkyl. (meth)acrylate monomer, the alkyl chain of which is saturated and contains from 18 to 22 carbon atoms; and at least one second compound selected from the modified alkylphenol-aldehyde resins. The invention also relates to the use of this composition of additives for lowering the viscosity of a liquid petroleum product such as a crude oil and for reducing the deposition of paraffins.

This invention provides a wax inhibitor composition comprising A) the reaction product obtainable by reaction of i) a carboxylic acid containing an optionally substituted cycloaliphatic hydrocarbyl residue with ii) an alkylene polyamine, B) a polymeric wax inhibitor, and C) an organic solvent.

A fuel composition including a middle distillate fuel oil obtained from the distillation of a pyrolysis oil and, as an additive, one or more of: (a) an antioxidant; and (b) a stabilising additive selected from (x) alkoxylated amine compounds; (y) aldehyde-alkylphenol copolymers; (z) acylated nitrogen compounds; and mixtures thereof. Also disclosed are a method and use for improving the stability of a fuel composition comprising a middle distillate fuel oil obtained from the distillation of a pyrolysis oil, which involve adding to the composition one or more additives selected from (a) and (b).