A process is presented for the production of high quality kerosene from lower quality feedstocks, including kerosene produced from coker units, or kerosene from cracking units. The process includes hydrotreating the feedstock to remove contaminants in the feedstock. The hydrotreated process stream is then treated in a trim reactor at higher pressure to reduce the bromine index of the kerosene.

A method for producing a base oil having a high ratio of weight percent molecules with monocycloparaffinic functionality to weight percent molecules with multicycloparaffinic functionality by hydroisomerization dewaxing a selected Fischer-Tropsch wax under hydroisomerization conditions including a hydrogen to feed ratio from about 712.4 to about 3562 liter H.sub.2/liter oil.

Systems and methods are provided for hydroprocessing a petroleum fraction, such as a bottoms fraction from a fuels hydrocracking process, to generate a lubricant base oil. The aromatic content of such a petroleum fraction can be reduced using a aromatic saturation stage with multiple catalyst beds, or alternatively using a reactor (or reactors) with multiple aromatic saturation stages. The catalysts in the various beds or stages can be selected to provide different types of aromatic saturation activity. An initial bed or stage can provide activity for saturation of 1-ring aromatics in the petroleum fraction. One or more subsequent beds or stages, operating at successively lower temperature, can then be used to reduce the multiple-ring aromatic content of the petroleum fraction.

Described are processes to produce base oils with one more improved properties, e.g., lower aromatics, economically and/or efficiently. In some embodiments the processes comprise a step that reduces the amount of residual refractory sulfur compounds prior to or simultaneous with a hydrofinishing step which advantageously provides base oils with lower aromatics than comparable processes.

A process for hydrotreating a sulfur-containing hydrocarbon feedstock may include producing a hydrotreated effluent by hydrotreating the feedstock in a three-phase trickle reactor to remove a first portion of the sulfur from the feedstock, separating the first hydrotreated effluent to give a hydrogen-containing gaseous fraction and a separated hydrotreated effluent, stripping the separated hydrotreated effluent to give a hydrogen sulfide-containing gaseous fraction and a stripped hydrotreated effluent, saturating the stripped hydrotreated effluent with hydrogen, and hydrotreating the hydrogen-saturated effluent in a two-phase reactor to remove a remaining second portion of the sulfur and produce a second hydrotreated effluent.

A process for hydrotreating a sulfur-containing hydrocarbon feedstock may include producing a hydrotreated effluent by hydrotreating the feedstock in a three-phase trickle reactor to remove a first portion of the sulfur from the feedstock, separating the first hydrotreated effluent to give a hydrogen-containing gaseous fraction and a separated hydrotreated effluent, stripping the separated hydrotreated effluent to give a hydrogen sulfide-containing gaseous fraction and a stripped hydrotreated effluent, saturating the stripped hydrotreated effluent with hydrogen, and hydrotreating the hydrogen-saturated effluent in a two-phase reactor to remove a remaining second portion of the sulfur and produce a second hydrotreated effluent.

A multi-stage process for reducing the environmental contaminants in an ISO8217 compliant Feedstock Heavy Marine Fuel Oil involving a core desulfurizing process and a ultrasound treatment process as either a pre-treating step or post-treating step to the core process. The Product Heavy Marine Fuel Oil complies 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 mass % to 1.0 mass. A process plant for conducting the process is also disclosed.

A multi-stage process for reducing the environmental contaminants in an ISO8217 compliant Feedstock Heavy Marine Fuel Oil involving a core desulfurizing process and a ultrasound treatment process as either a pre-treating step or post-treating step to the core process. The Product Heavy Marine Fuel Oil complies 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 mass % to 1.0 mass. A process plant for conducting the process is also disclosed.

A catalyst system for dewaxing of a hydrocarbon feedstock comprising at least two catalytic sections, the first section comprising a first dewaxing catalyst and a subsequent section comprising a second dewaxing catalyst, wherein the first dewaxing catalyst is a ZSM-12 zeolite based catalyst and the second dewaxing catalyst is a EU-2 and/or ZSM-48 zeolite based catalyst. The catalyst system displays enhanced performance when compared to systems containing either ony ZSM-12 based catalyst or EU-2/ZSM-48 based catalyst only.

Methods are provided for forming noble metal catalysts comprising both platinum and a second Group VIII metal, such as palladium, with improved aromatic saturation activity. Instead of impregnating a catalyst with both platinum and another Group VIII metal at the same time, a sequential impregnation can be used, with the Group VIII metal being impregnated prior to platinum. It has been discovered that by forming a Group VIII metal-impregnated catalyst first, and then impregnating with platinum, the distribution of platinum throughout the catalyst can be improved. The improved distribution of platinum can result in a catalyst with enhanced aromatic saturation activity relative to a catalyst with a similar composition formed by simultaneous impregnation.