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 of producing a fuel additive includes: passing a raffinate stream comprising C4 hydrocarbons through a hydrogenation unit, forming a first process stream; passing the first process stream through an extractive distillation unit, forming a C4 olefin stream; passing the C4 olefin stream through a stripper column, forming a purified C4 olefin stream; and forming the fuel additive by passing the purified C4 olefin stream through a hydration unit.

Endothermic fuel compositions comprising 50% or more by volume decahydronaphthalene, including cis-decahydronaphthalene, trans-decahydronaphthalene or a mixture thereof, for use as endothermic fuels in hypersonic vehicles and particularly for use in dual-mode ramjet or supersonic combustion ramjet air breathing engines. Methods for operating a ramjet or scram jet engine wherein the endothermic fuel is used for cooling the combustor and for combustion in the combustor.

Provided are automated systems and methods for measuring the physical properties of fuels in large storage tanks, and for blending butane into the fuels, including chemometric methods for controlling physical properties selected from volatility, butane content, and density of the fuel during the blending process.

A method of producing a fuel additive includes passing a feed stream comprising C4 hydrocarbons through a hydrogenation unit producing a hydrogenated stream; passing the hydrogenated stream through a distillation unit producing a first stream and a second stream; producing an isobutylene stream by passing the first stream through a molecular sieve unit; passing the isobutylene stream to a hydration unit as a feedstock for the fuel additive; and forming the fuel additive in the hydration unit.

A process for the treatment of a light naphtha feedstock that comprises normal paraffins and iso-paraffins may include separating the feedstock into a first iso-paraffin stream and a normal paraffin stream. The separating may be performed with 5A molecular sieves, a pressure of about 1-3 bars, and a temperature of 100-260° C. A product stream may be provided by subjecting the normal paraffin stream to at least one of steam cracking, isomerizing, and aromatizing.

A process for reducing the environmental contaminants in a ISO 8217 compliant Feedstock Heavy Marine Fuel Oil, the process involving: mixing a quantity of the Feedstock Heavy Marine Fuel Oil with a quantity of Activating Gas mixture to give a feedstock mixture; contacting the feedstock mixture with one or more catalysts to form a Process Mixture from the feedstock mixture; separating the Product Heavy Marine Fuel Oil liquid components of the Process Mixture from the gaseous components and by-product hydrocarbon components of the Process Mixture and, discharging the Product Heavy Marine Fuel Oil. The Product Heavy Marine Fuel Oil is compliant with ISO 8217 for residual marine fuel oils and has a sulfur level has a maximum sulfur content (ISO 14596 or ISO 8754) between the range of 0.05 % wt. to 0.5 % wt.. The Product Heavy Marine Fuel Oil can be used as or as a blending stock for an ISO 8217 compliant, IMO MARPOL Annex VI (revised) compliant low sulfur or ultralow sulfur heavy marine fuel oil. A device for conducting the process is also disclosed.

A multi-stage process for reducing the Environmental Contaminants in a Feedstock Heavy Marine Fuel Oil that is compliant with ISO 8217: 2017 Table 2 as a residual marine fuel except for the concentration of Environmental Contaminants, the process involving a core hydrotreating process and either a pre-treating step or post-treating step to the core process that is selected from a) a sulfur absorption process unit; b) an oxidative desulfurizing process unit; and c) a microwave treatment process unit. The Product Heavy Marine Fuel Oil is compliant with ISO 8217 Table 2 as residual marine fuel and preferably has a sulfur level has a maximum sulfur content (ISO 14596 or ISO 8754) between the range of 0.05% wt. to 0.5% wt. A commercial scale process plant for conducting the process is disclosed.

Systems and methods to provide renewable transportation fuels for internal combustion engines by converting renewable feedstocks into two or more intermediate hydrocarbon blend stocks and blending at least two of the two or more intermediate hydrocarbon blend stocks to produce the renewable transportation fuel. Methods and/or processes may include selecting sugar from a sugar source and introducing the sugar into one or more reactors. The sugar may be converted into an intermediate renewable hydrocarbon blend stock and sent to a separation unit to separate out an intermediate renewable gasoline unit. The process may include selecting and converting a lipid from a lipid source into a renewable diesel product. The renewable diesel product may be sent to a second separation unit to separate out renewable diesel and a low-grade naphtha. The low-grade naphtha and intermediate renewable gasoline may be blended to define a finished renewable gasoline.

In some embodiments, ethylene-propylene branched copolymers are synthesized with pyridyldiamido catalysts and a chain transfer agent, and their performance as viscosity modifiers in oil are detailed. In some embodiments, the present disclosure provides for ethylene-propylene branched copolymers having a shear thinning onset of less than about 0.01 rad/s and an HTHS value of less than about 3.3. In some embodiments, the ethylene-propylene branched copolymer is used as a viscosity modifier in a lubricating composition and a fuel composition.