An asphaltene dispersant composition is provided. The composition may contain an alkylphenol copolymer having the following repeating units (A) and (B): ##STR00001##
wherein, x is an integer from 1 to 200; y is an integer from 2 to 200; R.sub.1 is a straight or branched C.sub.1-C.sub.15 alkyl; and R.sub.2 is a straight or branched C.sub.2-C.sub.40 alkyl, wherein R.sub.2 is different than R.sub.1.

An alkylphenol copolymer, such as for use in a petroleum composition, is provided. The alkylphenol copolymer has the following repeating units (A) and (B): ##STR00001##
wherein, x is an integer from 1 to 200; y is an integer from 2 to 200; R.sub.1 is a straight or branched C.sub.1-C.sub.15 alkyl; and R.sub.2 is a straight or branched C.sub.2-C.sub.40 alkyl, wherein R.sub.2 is different than R.sub.1.

Fouling in a hydrocarbon refining process is reduced by adding to a crude hydrocarbon for a refining process, an additive combination including: (A) a polyalkenyl-substituted carboxylic acid or anhydride, and (B) an overbased metal hydrocarbyl-substituted hydroxybenzoate detergent,
where the mass:mass ratio of (A) to (B) is in the range of 10:1 to 1:10, and the treat rate of the additive combination is in the range of 5 to 1000 ppm by mass.

Use of a hydrocarbyl-substituted dicarboxylic acid for improving or boosting the separation of water from fuel oils and gasoline fuels which comprise additives with detergent action. A Fuel additive concentrate comprising the said hydrocarbyl-substituted dicarboxylic acid, certain additives with detergent action and optionally other customary additives and solvents or diluents.

Use of a hydrocarbyl-substituted dicarboxylic acid for improving or boosting the separation of water from fuel oils and gasoline fuels which comprise additives with detergent action. A Fuel additive concentrate comprising the said hydrocarbyl-substituted dicarboxylic acid, certain additives with detergent action and optionally other customary additives and solvents or diluents.

Use of a hydrocarbyl-substituted dicarboxylic acid for improving or boosting the separation of water from fuel oils and gasoline fuels which comprise additives with detergent action. A Fuel additive concentrate comprising the said hydrocarbyl-substituted dicarboxylic acid, certain additives with detergent action and optionally other customary additives and solvents or diluents.

A diesel fuel composition comprising as an additive an ester compound which is the reaction product of an optionally substituted polycarboxylic acid or an anhydride thereof and a polyhydric alcohol of formula H(OR).sub.nOH, wherein R is an optionally substituted alkylene group and n is at least 1.

A composition comprising a distillate fuel, an oligomer portion comprising at least one dimethoxymethane oligomer, and a stabilizer comprising one or more alcohols. A composition comprising a distillate fuel, and an oligomer portion comprising at least one dimethoxymethane oligomer, DMMn, wherein n is less than 3 and/or greater than 4. A composition comprising a distillate fuel, and less than 10 volume percent of an oligomer portion, wherein the oligomer portion comprises at least one dimethoxymethane oligomer. A method comprising separating, from a mixture of DMMn oligomers, one or more DMMn fractions comprising oligomers of a desired chain length n, and combining a desired amount of one or more of the separated DMMn fractions with a distillate fuel to provide a fuel composition. A composition comprising a distillate fuel that includes renewable distillate fuel, DMMn and/or alcohol.

The invention relates to aqueous polymer dispersions comprising at least one polymer obtainable by the reaction of at least one monomer M1 of the general formula H.sub.2CCHC(O)OR (I), wherein R is an unbranched alkyl chain comprising from 18 to 22 carbon atoms, and optionally at least one monomer M2. The invention relates moreover to a method for the preparing of such aqueous polymer dispersion and the use thereof as pour point depressant for crude oil, petroleum, and petroleum products.

The present invention relates to novel uses of corrosion inhibitors in fuels and lubricants.