Lubricant compositions comprising a base oil, one or more antioxidants selected from a group consisting of N-α-naphthyl-N-phenylamine antioxidants and diphenylamine antioxidants; and a sulfur-containing additive comprising up to seven carbon atoms exhibit outstanding oxidative stability and non-corrosion properties. The N-α-naphthyl-N-phenylamine antioxidants plus diphenylamine antioxidants in total may be present from about 0.2 wt % to about 0.8 wt %, based on the total weight of the lubricant composition. The sulfur provided by the sulfur-containing additive may be present from about 50 ppm to about 1000 ppm by weight, based on the total weight of the lubricant composition.

The present invention relates to a lubricant composition, in particular for a gas or steam turbine, comprising: —at least one base oil; —at least one phenylnaphthylamine (PAN) compound, preferably alkylphenyl-α-naphthylamine (APAN) compound; —at least one diphenylamine (DPA) compound, preferably dialkyl-diphenylamine compound; and —at least one phosphite ester compound, preferably triaryl phosphite ester compound; in which the ratio by weight between said diphenylamine compound(s) and said phosphite ester compound(s) is strictly greater than 1.0.

Systems and methods for automatic maintenance of lube oil quality include a storage tank for storing fresh lube oil, a lube oil reservoir containing a volume of operational lube oil, and an oil disposal tank. A first controllable flow system transports lube oil from the reservoir to the oil disposal tank, and a second controllable flow system transports fresh lube oil from the storage tank to the reservoir. Provided are a level transmitter to measure a level of lube oil within the reservoir and an antioxidant sensor to measure a concentration of antioxidant level inside the lube oil reservoir. A control system activates and deactivates the first controllable flow system based upon the concentration of antioxidant measured by the antioxidant sensor, and activates and deactivates the second controllable flow system based upon the level of lube oil measured by the level transmitter.

Disclosed is the use of specific organophosphorus compounds as anti-wear agents in an oil so as to prevent and/or reduce the neurotoxicity of the oil and/or for the prophylaxis of aerotoxic syndrome in the instance of a fume event.

Disclosed is a method of lubrication including a step of lubricating a machine with a lubricating composition, the lubricating composition including 20-100% ionic liquid or of a mixture of several ionic liquids. The ionic liquid or the mixture is selected from at least: an anion A.sup.− chosen from sulfonylimides, the substituent(s) of which is (are) independently chosen from a fluoroalkyl, fluoroether, perfluorinated alkyl or perfluoroether group; and a cation C.sup.+ including a nitrogen-containing heterocycle or a quaternary ammonium, the substituent(s) of which is (are) independently chosen from: a hydrogen atom or alkyl, alkoxy, fluorinated alkyl, perfluorinated alkyl, alkylsilane, alkyl alcohol, vinyl, alkyl allyl, ether or polyether groups having a linear or branched chain having 1-3 carbon atoms. The deposition start temperature in thin film of the ionic liquid or of the mixture of ionic liquids is at least equal to 330° C. The lubricating composition reduces deposits formed in the machine.

A liquid blend of octylated phenyl-α-naphthylamine, and at least one low molecular weight aromatic ester, wherein the octylated phenyl-α-naphthylamine is present from about 15% to about 35% by weight of the blend, as well as a lubricating composition comprising a lubricant base and an amount of the blend which provides up to 2.0% by weight of the octylated phenyl-α-naphthylamine in the composition.

Lubricant compositions comprising a base oil, one or more antioxidants selected from a group consisting of N-α-naphthyl-N-phenylamine antioxidants and diphenylamine antioxidants; and a sulfur-containing additive comprising up to seven carbon atoms exhibit outstanding oxidative stability and non-corrosion properties. The N-α-naphthyl-N-phenylamine antioxidants plus diphenylamine antioxidants in total may be present from about 0.2 wt % to about 0.8 wt %, based on the total weight of the lubricant composition. The sulfur provided by the sulfur-containing additive may be present from about 50 ppm to about 1000 ppm by weight, based on the total weight of the lubricant composition.

Disclosed is a method using at least one anti-wear additive in an oil, the at least one anti-wear additive including at least one polyphosphorus compound to reduce and/or prevent the neurotoxicity of the oil or for the prophylaxis of aerotoxic syndrome, preferably in case of fume event.

The invention relates to the use of an oil that does not include tricresyl phosphate and includes as an anti-wear additive at least one diphosphorus compound for the prophylaxis of aerotoxic syndrome, especially in case of fume event. It also relates to the oil as such.

Disclosed is an oil that does not include tricresyl phosphate and includes as an anti-wear additive at least one diphosphorus compound for the prophylaxis of aerotoxic syndrome, especially in case of fume event. It also relates to a lubrication method utilizing such oil.