Diesel boiling-range fuel blends including renewable diesel, biodiesel, and petrodiesel, where the diesel boiling-range fuel blend is capable of producing a minimal volume change of at least one swellable elastomer in a diesel boiling-range fuel system are provided herein. Methods of making the diesel boiling-range fuel blend as well as methods of reducing swellable elastomer shrinkage are also provided herein.

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).

Methods for producing fuel compositions with predetermined desirable properties are disclosed. Feedback control can be employed to meter precise amounts of fuel composition components while monitoring fuel composition properties to obtain fuel compositions having specifically defined properties.

Base compounds including 1,3-oxazinan-6-one derivatives of N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acids and paraformaldehyde, and their application as corrosion inhibitors with multifunctional properties serving as inhibitory/dispersant of asphaltene in production processes, transportation, refining and storage of crude oil and derivatives. The corrosion inhibitor with inhibitory/dispersant of asphaltenes properties comprises an active substance base of 1,3-oxaninan-6-ones and hydrocarbon solvents such as benzene, toluene, mixed xylenes, o-xylene, m-xylene and p-xylene, diesel, kerosene, jet fuel, alcohols, aliphatic branched and unbranched alcohols containing from 3 to 10 carbon atoms, such as isopropanol, butanol and pentanol, and mixtures of hydrocarbon solvents with aliphatic branched or unbranched liquid fuels. In addition, a process for obtaining 1,3-oxazinan-6-ones derivatives of N-alkyl or N-alkenyl or N-cycloalkyl or N-aryl propionic acids and paraformaldehyde is described.

The invention relates to a block copolymer and the use thereof as a cold resistance additive of a fuel or combustible. The block copolymer comprises: (i) a block A consisting of a chain of structural motifs derived from at least one ,-unsaturated alkyl methacrylate or acrylate monomer; and (ii) a block B consisting of a chain of structural motifs derived from at least one ,-unsaturated monomer containing at least one aromatic ring. The invention also relates to an additive concentrate containing such a copolymer and to the use thereof as a TLF booster and, advantageously, as an anti-sedimentation additive.

The invention relates to a block copolymer and the use thereof as a cold resistance additive of a fuel or combustible. The block copolymer comprises: (i) a block A consisting of a chain of structural motifs derived from at least one ,-unsaturated alkyl methacrylate or acrylate monomer; and (ii) a block B consisting of a chain of structural motifs derived from at least one ,-unsaturated monomer selected from styrene derivatives, the aromatic ring of which is substituted by at least one group R selected from the groups: C.sub.1 to C.sub.24 alkyl esters, and preferably acyclic linear or branched C.sub.1 to C.sub.12 hydrocarbonated chains, said chain being substituted by at least one group containing a quaternary ammonium salt. The invention also relates to an additive concentrate containing such a copolymer and to the use thereof as an anti-sedimentation additive, and advantageously, as a TLF booster additive.

A method of preventing or reducing the level of degradation of an organic substrate is described, wherein a composition is formed that includes the organic substrate together with an effective amount of a sacrificial base and a diarylamine antioxidant.

A fuel composition is described. The composition contains a hydrocarbon-based fuel boiling in the gasoline or diesel range; a carrier fluid comprising an alkyl polyethoxylate having the following structure:

##STR00001##

where each R.sup.2 and R.sup.3 is independently hydrogen, C.sub.1-C.sub.4 hydrocarbyl group, or C.sub.1-C.sub.3 alcohol, where R.sup.1 is C.sub.4-C.sub.100 hydrocarbyl group, carboxyl group, ether group, thioether group, or aromatic group, wherein x is from 1 to 20, or a hydrocarbyl phenol having the following structure

##STR00002##

wherein R is a hydrocarbyl group from C.sub.4-C.sub.100; an amine-based detergent given by formula 2, R.sup.4O(CH.sub.2).sub.yNHR.sup.5, where the amine-based detergent is present in about 10 ppm to about 750 ppm by weight based on total weight of the fuel composition; where R.sup.4 is a hydrocarbyl group having 8 to 20 carbons, R.sup.5 is hydrogen or (CH.sub.2).sub.zNH.sub.2 moiety, and where y, z are independently integers having a value of 2 or greater; and one or more nitrogen-containing detergent.

An anti-static fuel additive composition and method for using the composition to reduce or prevent buildup of electrostatic charge is described. The anti-static fuel additive composition comprises a polysulfone and a copolymer derived from reaction of an alkanolamine and a hydrocarbyl-substituted 4-membered to 7-memebered ring anhydride; for example, a hydrocarbyl-substituted succinic anhydride, a hydrocarbyl-substituted maleic anhydride, a hydrocarbyl-substituted phthalic anhydride, or a combination thereof.

Methods of making antidegradant compounds are disclosed in which a p-phenylenediamine is reacted with a diol to obtain mixtures comprising the antidegradant compounds.