Abstract: An improved solvent refining process for hydrocarbon oils such as asphalt-free lube fractions and diesel fuels is provided by recycling an inert gas such as nitrogen through the contact zone of the extraction tower.

Abstract: An improved solvent extraction process is described for the preparation of lube oil products, the improvement whereby the extract phase is subjected to a voltage gradient.

Abstract: Petroliferous material of tar sands is processed to recover both low and higher boiling distillate material in a sequential combination operation involving thermal distillation and solvent extraction. Residue of solvent extraction is gasified with hot sand product of gasification step used in the thermal distillation operation.

Abstract: Iminodiimides of 3,3',4,4'-benzophenonetetracarboxylic dianhydride are novel compounds having utility as pour depressants and as UV stabilizers in hydrocracked oils.

Abstract: Hydrocarbon oils such as residual petroleum oils are efficiently deasphalted and demetallized with recovery of high quality asphalt by contact with a liquid mixture of at least two of the components selected from hydrogen sulfide, carbon dioxide and propane. The recovered deasphalted oil, which is characterized by reduced metal and sulfur content, may be used as charge stock to the fluid catalytic cracking process or to the hydrocracking process.

Abstract: Petroliferous material of tar sands is processed to recover material boiling below 850.degree. F. with higher boiling material converted to high BTU fuel gas and with heat developed transported to improve the thermal efficiency of the combination operation.

Abstract: Nitrogen compounds are removed from liquid hydrocarbons such as oils of lubricating viscosity by contacting the hydrocarbons with a solid sorbent, having anhydrous acid gas adsorbed therein. The solid sorbent, which may be amorphous, e.g. silica-alumina, or crystalline, e.g., NaX, is thereafter regenerated for reuse.

Abstract: Iminodiimides of 3,3',4,4'-benzophenonetetracarboxylic dianhydride are novel compounds having utility as pour depressants and as UV stabilizers when incorporated into lubricant compositions.

Abstract: The treating capacity of a finishing unit for oils of lubricating viscosity is increased and the quality of oil treated therein is improved in a process comprising contacting regenerated clay adsorbent from said finishing unit with anhydrous acid gas prior to returning it to the adsorbent bed of said unit, and thereafter contacting said oil with said acid gas treated adsorbent.

Abstract: An improved process for preparing a stabilized lubricating oil resistant to oxidation and sludge formation upon exposure to a highly oxidative environment, such as when metals are present and an overbased component is present in the lubricating oil, is provided. In the present process wherein a lubricating oil stock to be upgraded is contacted with elemental sulfur in the presence of a catalyst material selected from the group consisting of alumina, aluminosilicate, a metal of Groups II-A, II-B, VI-B or VIII of the Periodic Table of Elements, an oxide of a metal of Groups II-A, II-B, VI-B or VIII, a sulfide of a metal of Groups II-A, II-B, VI-B or VIII, clay, silica, silica combined with an oxide of a metal of Groups II-A, III-A, IV-B or V-B, and combinations thereof, at relatively low temperatures of from about 150.degree. to about 225.degree.

Abstract: Grease compositions are provided containing, as thickeners, alkali metal salts of a gamma keto acid.

Abstract: A method is provided for reactivation of color removal activity of hydrofinishing catalyst which comprises contacting aged hydrofinishing catalyst exhibiting degraded color removal activity with a small amount of added elemental sulfur dissolved in hydrocarbon oil under mild contact conditions for a time sufficient to reactivate the color removal activity of the catalyst.

Abstract: A two-step process for preparing a stabilized lubricating oil resistant to oxidation and sludge formation upon exposure to a highly oxidative environment is provided. The first step of the present process comprises contacting a lubricating oil stock with elemental sulfur in the presence of a catalyst material selcted from the group consisting of alumina, silica, aluminosilicate, a metal of Groups II-A, II-B, VI-B or VIII of the Periodic Table of Elements, an oxide of a metal of Groups II-A, II-B, VI-B or VIII, a sulfide of a metal of Groups II-A, II-B, VI-B or VIII, clay, silica combined with an oxide of a metal of Groups II-A, III-A, IV-B or V-B, and combinations thereof in a flow reactor or under conditions comparable to those existing in a flow reactor. The second step of the present process comprises contacting the product of the first step with hydrogen in the presence of alumina impregnated with at least about 10 weight percent of MoO.sub.3 and at least about 2.