Abstract: An integrated hydrocracking and solvent deasphalting process that provides for removal from the heavy oil recycle stream heavy polycyclic aromatic compounds formed in the hydrocracking step and recycling the resulting deasphalted paraffinic oil as a feed to the hydrocracker reactor of the process for further conversion.

Abstract: A process for making high cetane diesel. The process includes contacting a distillate feedstock in a hydrodenitrogenation and polyaromatics saturation zone and passing the resulting treated effluent to a high pressure stripping zone. The stripped liquid fraction from the high pressure stripping zone is contacted with a base metal catalyst under monoaromatics saturation conditions to yield a reactor product. The reactor product undergoes a separation to provide a hydrogen portion and a dearomatized distillate portion with the hydrogen portion being recycled and introduced into the high pressure stripping zone.

Abstract: An integrated hydrocracking, vacuum distillation and solvent deasphalting process that provides for controlling the amount of polycyclic aromatic hydrocarbons in a heavy oil recycle stream by separating a portion of the heavy oil recycle stream into various fractions in a vacuum distillation unit, and processing the various fractions in a manner, including solvent deasphalting, that allows for the control of the polycyclic aromatic hydrocarbons in the heavy oil recycle stream.

Abstract: A process that provides for the improvement of the properties of a distillate feedstock that has significant concentrations of nitrogen and polyaromatic compounds. The process includes a first reaction zone that uses a base metal catalyst and is operated under high pressure conditions to provide for the hydrodenitrogenation of organic nitrogen and saturation of polyaromatic compounds contained in the distillate feedstock. The first reaction zone treated effluent is separated into a heavy fraction and a lighter fraction with the heavy fraction being charged to a second reaction zone that also uses a base metal catalyst and is operated under high pressure conditions to provide for the saturation of monaromatic compounds that are contained in the heavy fraction. The inventive process provides for a high quality, low-sulfur and low-nitrogen diesel product that has a significantly lower aromatics content than the distillate feedstock and having a high value for its high Cetane Index.

Abstract: An integrated hydrocracking, vacuum distillation and solvent deasphalting process that provides for controlling the amount of polycyclic aromatic hydrocarbons in a heavy oil recycle stream by separating a portion of the heavy oil recycle stream into various fractions in a vacuum distillation unit, and processing the various fractions in a manner, including solvent deasphalting, that allows for the control of the polycyclic aromatic hydrocarbons in the heavy oil recycle stream.

Abstract: An integrated hydrocracking and solvent deasphalting process that provides for removal from the heavy oil recycle stream heavy polycyclic aromatic compounds formed in the hydrocracking step and recycling the resulting deasphalted paraffinic oil as a feed to the hydrocracker reactor of the process for further conversion.

Abstract: A process that provides for the improvement of the properties of a distillate feedstock that has significant concentrations of nitrogen and polyaromatic compounds. The process includes a first reaction zone that uses a base metal catalyst and is operated under high pressure conditions to provide for the hydrodenitrogenation of organic nitrogen and saturation of polyaromatic compounds contained in the distillate feedstock. The first reaction zone treated effluent is separated into a heavy fraction and a lighter fraction with the heavy fraction being charged to a second reaction zone that also uses a base metal catalyst and is operated under high pressure conditions to provide for the saturation of monaromatic compounds that are contained in the heavy fraction. The inventive process provides for a high quality, low-sulfur and low-nitrogen diesel product that has a significantly lower aromatics content than the distillate feedstock and having a high value for its high Cetane Index.

Abstract: A process for making high cetane diesel. The process includes contacting a distillate feedstock in a hydrodenitrogenation and polyaromatics saturation zone and passing the resulting treated effluent to a high pressure stripping zone. The stripped liquid fraction from the high pressure stripping zone is contacted with a base metal catalyst under monoaromatics saturation conditions to yield a reactor product. The reactor product undergoes a separation to provide a hydrogen portion and a dearomatized distillate portion with the hydrogen portion being recycled and introduced into the high pressure stripping zone.

Abstract: Supports for catalytic reforming catalysts are prepared by doping ZrO.sub.2 with tantalum. The catalyst may contain a Group VII or Group VIII metal and/or an acidic component.