A method of marking a hydrocarbon fuel, the method comprising adding to said hydrocarbon fuel a tracer compound for marking the hydrocarbon fuel, the tracer compound being a substituted fluorene having a structure of Formula (I): wherein R1 and R2 are the same or different and selected from hydrogen, straight chain, branched or cyclic alkyl groups, phenyl or substituted phenyl groups, benzyl or substituted benzyl groups, or R1 and R2 form a single substituent linked intramolecularly to each other, or R1 and R2 are ether groups excluding acetal groups, wherein R3 and R4 are the same or different and selected from hydrogen, straight chain, branched or cyclic alkyl groups, phenyl or substituted phenyl groups, benzyl or substituted benzyl groups, and wherein at least one of R1, R2, R3, and R4 is not hydrogen.

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A method for preparation of a reagent for reducing hydrodynamic drag of a turbulent flow of liquid hydrocarbons in pipelines, characterized by a high polymer content of at least 75 wt %, including mixing a 0.1-1.5 mm polymer reducing the hydrodynamic drag of a turbulent flow of liquid hydrocarbons with polymer non-solving solvents. The prepared product is a commodity form of the reagent with a high polymer content of at least 75 wt % used to reduce the hydrodynamic drag of the flow of liquid hydrocarbons in pipelines. The product prepared according to the described method is injected into the flow of hydrocarbon fluid transported through the pipeline using the injection apparatus that mechanically moves the product using a screw auger or screw feeder.

A method is disclosed for converting biomass into a fuel additive, the method comprising: liquefying the biomass to form a liquor; neutralizing the liquor; precipitating lignin out of the liquor; extracting furfural (FF) and 5-hydroxymethylfurfural (HMF) from the liquor; and hydrodeoxygenating (HDO) the extracted furfurals over a Cu—Ni/TiO.sub.2 catalyst. The catalyst for hydrodeoxygenating (HDO) furfural (FF) and 5-hydroxymethylfurfural (HMF) to methylated furans comprises copper-nickel (Cu—Ni) particles supported on titanium dioxide (TiO.sub.2), and wherein the copper-nickel particles form core-shell structures in which copper (Cu) is enriched at a surface of the catalyst.

A process and system for separating bio-gasoline, bio-diesel and bio-fuel oil fractions from a bio-oil, and for producing a renewable gasoline including at least in part the bio-gasoline fraction, is provided. The process comprises separating bio-oil into a bio-gasoline fraction and a heavy fraction based on their boiling points. At least a portion of the bio-gasoline fraction is directly blended with a petroleum-derived gasoline, without any prior hydrotreatment, to thereby provide a renewable gasoline composition.

Embodiments of the invention provide a method of inhibiting precipitation of biodiesel fuel components. The method includes providing a biodiesel fuel composition; providing a copolymer comprising at least first and second polymer units, said first polymer units derived from a carboxylic acid anhydride and said second polymer units derived from an olefin; and blending said copolymer with the biodiesel fuel to form a treated fuel composition. Alternatively, instead of the copolymer, a dialkylene glycol additive can be provided. Embodiments of the invention provide a method of reducing the cold soak filter blocking tendency of a biodiesel fuel composition.

The invention relates to liquid hydrocarbons containing cyclic ortho esters as dehydrating dehydrating icing inhibitors and to methods of using the compounds. The liquid hydrocarbons include fuels such aviation fuels, lubricants, hydraulic fluids and hydrocarbon solvents.

A Liquid, comprising an hydrophobic flavonoid derivative electrochemically non-active, that is capable of restoring its electrochemical activity, the concentration of the flavonoid derivative being 10 ppm by weight or less, and an organic substance in an amount of 90% by weight or more.

The present disclosure provides methods for identifying a hydrocarbon fuel, such as the presence and/or amounts of marker compounds having a fluorescence intensity and, through correlation, the presence and/or amounts of additive package(s) within the hydrocarbon fuel.

A biodiesel fuel consisting of a dioxolane with one to three alkyl groups, a (CH.sub.2).sub.nCH.sub.3 alkyl group where n ranges from 6 to 14, and the dioxolane has a total number of carbons that is equal to or less than 24 carbons.

A method of marking a hydrocarbon liquid comprising adding to said hydrocarbon liquid a tracer compound, the tracer compound being a substituted biphenol ether having a core structure of Formula I, wherein the two R groups are the same or different and selected from straight chain, branched or cyclic alkyl groups, phenyl or substituted phenyl groups, benzyl or substituted benzyl groups, or the two R groups form a single substituent linked intramolecularly to both oxygen atoms, and wherein one or both of the aromatic rings of the core structure is further substituted with at least one non-planar group.

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