A lubricant composition comprising an oil of lubricating viscosity and about 0.01 to about 5 percent by weight of a (thio)phosphoric acid salt (phos-amine salt) of at least one hydrocarbyl amine. The hydrocarbyl amine may be a hindered hydro-carbyl amine, an aromatic hydrocarbyl amine, or a combination thereof.

Provided is a lubricating oil composition comprising a base oil (A) containing a polyalkylene glycol (A1) and a polyol ester (A2), a phosphorus-based rust inhibitor (B), and an antioxidant (C) containing an amine-based antioxidant (C1). The lubricating oil composition exhibits a strong effect for suppressing sludge sedimentation even when used for an extended period of time in a high-temperature environment, and has excellent demulsibility and rust preventive properties, and therefore, can be suitably used in turbomachinery, compressors, hydraulic equipment, and machine tools.

A lubricating oil composition for a gas engine containing: a base oil (A), at least one overbased calcium detergent (B) selected from the group consisting of calcium salicylate (B1) and calcium phenate (B2), alkenyl succinimide (C), and a hindered amine-based antioxidant (D), where the content (X) of calcium atoms derived from the component (B) is less than 0.090% by mass based on the total amount of the lubricating oil composition; the content (Y) of calcium carbonate contained in the component (B) is 0.060% by mass or more based on the total amount of the lubricating oil composition; the content of boron atoms derived from the component (C) is less than 0.020% by mass based on the total amount of the lubricating oil composition, and the content of the component (D) is more than 0.20% by mass based on the total amount of the lubricating oil composition.

The present disclosure relates generally to lubricating compositions and methods of making and using the same. Specifically, the present disclosure relates to lubricating compositions and method of making and using the same for modifying friction at a metal-elastomer contact, and therefore improving at least one of elastomer lifetime, reducing elastomer wear, reducing metal wear, reducing energy consumption or a combination thereof. More specifically, one aspect of the present disclosure relates to lubricating compositions including at least two base oils with a viscosity difference between the first and second base oils; another aspect of the present disclosure relates to lubricating compositions comprising an additive that can modify friction at a metal-elastomer contact.

An antioxidant polymer (e.g., oligomer) composition comprising repeat units of diphenylamine monomers of formula I

##STR00001##

wherein R is H, C.sub.1-C.sub.18 alkyl, C.sub.2-C.sub.18 alkenyl, C.sub.2-C.sub.18 alkynyl, C(O)C.sub.1-C.sub.18 alkyl, C(O)aryl and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each independently H or a linear or branched C.sub.1-C.sub.18 alkyl, C.sub.1-C.sub.18 alkoxy, C.sub.1-C.sub.18 alkylamino, C.sub.1-C.sub.18 dialkylamino, C.sub.1-C.sub.18 alkylthio, C.sub.2-C.sub.18 alkenyl, C.sub.2-C.sub.18 alkynyl or C.sub.7-C.sub.21 aralkyl and wherein the number average molecular weight (Mn) of the polymer is from about 350 g/mol to about 5000 g/mol are highly effective antioxidants in lubricant compositions. The polymer compositions may be prepared by a process comprising subjecting diarylamine monomers to dehydrocondensation conditions.

A method for the regeneration of used lubricating oils to produce lubricant base oils includes the steps of (a) removing resin and impurities by distillation, (b) catalytic oxidation treatment and (c) adsorption process. The method can efficiently reduce the color, metal ions, and sulfur content under mild reaction conditions at low cost and obtain high yield of regenerated oil above 85 wt. %.

The present invention relates to lubricant compositions that are especially suitable for the lubrication of turbines or (turbo)compressors which serve to compress chlorine and/or chlorinated products. The lubricant composition comprises a base oil, an antihydrolysis component and a rust and oxidation inhibitor.

Disclosed are solvency enhancer compositions, for example, as additives to lubricating oils and as formulated in lubricating oil compositions and associated methods of preparation and use thereof. The compositions and methods can dissolve at least one of oxidation products and other organic polar compounds, due to lubricant degradation, formed and suspended in oil compositions including adding an effective amount of a solvency enhancer to the oils, wherein the solvency enhancer includes Guerbet alcohols. Further described are methods for dissolving organic deposits in an oil system including adding an effective amount of a solvency enhancer to the oil system, wherein the solvency enhancer includes Guerbet alcohols. Also provided are methods for preventing sludge and varnish formation in in-service oils including adding an effective amount of a solvency enhancer to the oils, wherein the solvency enhancer includes Guerbet alcohols.

Provided are microalgal compositions and methods for their use. The microalgal compositions include lubricants that find use in industrial and other applications.

Provided is a lubricating oil composition containing a base oil (A) and an amine-based antioxidant (B), wherein the component (B) contains a phenyl-naphthylamine (B1), an alkylphenyl-naphthylamine (B2) and a di(alkylphenyl)amine (B3), the content of the component (B1) is 2.0 to 10.0% by mass relative to 100% by mass of the total amount of the component (B), the content of the component (B2) is 40.0 to 90.0% by mass relative to 100% by mass of the total amount of the component (B), and the content of the component (B3) is 8.0 to 50.0% by mass relative to 100% by mass of the total amount of the component (B). The lubricating oil composition maintains excellent oxidation stability even in long-term use in high-temperature environments, and has an excellent lifetime and is excellent also in a sludge preventing effect.