The present invention relates to a process for preparing grafted polyalkyl(meth)acrylates (PAMAs) containing dispersant repeating units in the polymer backbone as well as in the grafted layer, which polymers are characterized by a low sulfur content, the products available by this process and their use as an additive to fuels, especially to middle distillates and blends thereof. The present invention further relates to a composition comprising the grafted polyalkyl(meth)acrylates prepared by the process according to the present invention and the use of said composition as an additive component to fuels, especially to middle distillates and blends thereof, and for improving the cold flow properties of fuel oil and fuel oil compositions, especially to middle distillate fuels and blends thereof.

A process dissolves or disperses asphaltenes from marine fuels by using at least one quaternary ammonium compound. A weight ratio of aromatics to asphaltenes in the marine fuel is not more than 7.0. A marine fuel is produced that includes saturates, aromatics, and asphaltenes in addition to at least one quaternary ammonium compound. Another process reduces or prevents fouling caused by asphaltenes in a marine fuel.

A process dissolves or disperses asphaltenes from marine fuels by using at least one quaternary ammonium compound. A weight ratio of aromatics to asphaltenes in the marine fuel is not more than 7.0. A marine fuel is produced that includes saturates, aromatics, and asphaltenes in addition to at least one quaternary ammonium compound. Another process reduces or prevents fouling caused by asphaltenes in a marine fuel.

Described herein are associative polymers capable of controlling formation of particulate matter from a non-polar ignitable composition upon ignition of the non-polar ignitable composition, alone or in combination with control of a physical and/or chemical property of the non-polar compositions and related compositions, methods and systems. Associative polymers herein described have a non-polar backbone 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.

Inhibiting gas hydrate formation while transporting hydrocarbon fluids may include providing a kinetic gas hydrate inhibitor, adding the kinetic gas hydrate inhibitor to a fluid capable of producing gas hydrates, and transporting the fluid that comprises the kinetic gas hydrate inhibitor. Generally a kinetic gas hydrate inhibitor may include a heterocyclic compound comprising nitrogen, e.g., polyvinyl pyrrolidone).

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

Inhibiting gas hydrate formation while transporting hydrocarbon fluids may include providing a kinetic gas hydrate inhibitor, adding the kinetic gas hydrate inhibitor to a fluid capable of producing gas hydrates, and transporting the fluid that comprises the kinetic gas hydrate inhibitor. Generally a kinetic gas hydrate inhibitor may include a heterocyclic compound comprising nitrogen, e.g., poly(vinyl pyrrolidone).

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.

The present invention is a polymer having structural units, units of formula I, units of formula II and units of either formula IIIa or formula IIIb:

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The polymer improves the low-temperature properties of fuel oils from petroleum sources and especially from vegetable or animal sources.

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