The invention provides a lubricating composition comprising an oil of lubricating viscosity and synergistic mixture of a functionalized ethylene--olefin copolymer, a poly(meth)acrylate block polymer having a substantially oil soluble block and a substantially oil insoluble block. The invention also provides a method of lubricating a mechanical device using such a lubricating composition.

A lubricant composition of an oil of lubricating viscosity and a phosphite ester reaction product of a monomeric phosphorous acid or an ester thereof with a first alkylene diol having two hydroxy groups in a 1,4 or 1,5 or 1,6 relationship and a second, alkyl-substituted, diol being a substituted 1,3-propylene diol, exhibits good wear and frictional performance.

A composition whereby a hydrocarbon-based base oil is used and in this base oil are incorporated, in terms of the total amount of the composition, 30 to 300 ppm of overbased calcium salicylate and, in net weight in terms of the total amount of the composition, 0.07 to 2.0 mass % of a non-dispersant polymethacrylate having a weight average molecular weight of 5000 to 200,000. The electrical conductivity at 25 C. of this composition is not less than 200 pS/m, the flash point is not less than 240 C., the pour point is 40 C. or lower and the micro clutch friction coefficient at 140 C. is not less than 0.08. This lubricating oil composition may be used in machines fitted with electronic control apparatus and can impart conductivity so as to inhibit the occurrence of noise which is detrimental to electronic control.

The invention provides a lubricating composition containing an oil of lubricating viscosity and an ashless ketone compound with at least one of a hydroxy group and an ether linkage attached to the carbon atom adjacent to the carbonyl carbon of the ketone, especially -hydroxyketone. The invention further relates to methods of lubricating an internal combustion engine by supplying the described lubricating composition to the internal combustion engine. The invention further relates to the use of the -hydroxyketone compound as a friction modifier and an antiwear agent.

The present invention provides method for separating contaminants from a liquid mixture comprising the steps of a) providing a feed of said liquid mixture to be purified, b) adding a separation aid to the liquid mixture to be purified, wherein said separation aid is capable of binding said contaminants and c) supplying a flow of compressed air into said feed after step b) has been performed to provide a feed comprising air. The method further comprises steps d) removing air from said feed comprising air to provide a deaerated feed; and e) supplying said deaerated feed to a separator, and f) separating a phase comprising contaminants and said separation aid from said liquid mixture in said separator, wherein the separation aid added in step b) is insoluble in said liquid mixture at the separation conditions in step f). The present invention further provides a system for separating contaminants from a liquid mixture.

Ethylene-C.sub.3-C.sub.10 alpha olefin copolymers, dispersants and lubricating oils/fuel compositions incorporating dispersants, and related methods are generally described herein. The copolymer may comprise ethylene-derived units and C.sub.3-C.sub.10 alpha-olefin-derived units. The C.sub.3-C.sub.10 alpha-olefin-derived units may have a carbon number from three to ten. For example, the C.sub.3-C.sub.10 alpha-olefin-derived units may be propylene-derived units.

A fluid contains a base oil consisting of an alcohol-initiated polyalkylene glycol where polyalkylene glycol component is selected from a homopolymer of 1,2-butylene oxide and copolymer of 1,2-butylene oxide and propylene oxide; a glycerol-initiated unsaturated ester that is free of tertiary carbon atoms and quaternary carbon atoms; and an antioxidant.

The invention relates to phosphorous-containing compounds useful as antiwear additive components, lubricant additive compositions and lubricant compositions each comprising such compounds, methods for making and using the same, including methods of lubricating machines and machine parts and methods of extending the useful life of elastomeric seal components of such machines.

In accordance with the disclosure, one aspect of the present application is directed to a lubricant additive composition. The lubricant additive composition includes a component or mixture of components selected from (a) an aminoalkylphosphonic acid dialkyl ester; (b) a cyclized product of an aminoalkylphosphonic acid dialkyl ester; and a mixture of (a) and (b). Preparation and use of the additive composition in a lubricant for antiwear and/or friction reduction are also disclosed.

A lubricating oil composition contains: a base oil with a kinematic viscosity at 40 degrees C. in a range from 1 mm.sup.2/s to 200 mm.sup.2/s, a viscosity index of 80 or more and a sulfur content of less than 0.03 mass %; a component (A) being a polyacrylate compound with a mass average molecular weight in a range from 10,000 to 100,000; and a component (B) being at least one of phosphorus compounds represented by a formula (1) below. A content of the component (B) is in a range from 0.05 mass % to 2.0 mass % of a total amount of the composition, and a viscosity index of the composition is 160 or more. ##STR00001##