Provided are a fluoropolyether compound having high heat resistance and capable of maintaining a surface protection layer even under high temperature, and a lubricant and a magnetic disk that contain the fluoropolyether compound. The fluoropolyether compound includes: three groups whose main chain contains a perfluoropolyether chain; and a trivalent linking group represented by Formula (1) below, the three groups being bound together via the trivalent linking group:

##STR00001##

where R.sub.1 is a saturated hydrocarbon group having 1 to 3 carbon atoms, a perfluoroalkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a hydroxyl group, or an amino group, and A.sub.1, A.sub.2, and A.sub.3 are each independently an aromatic group.

Provided are a magnetic disk and, in particular, a compound which makes it possible to realize a lubricant having excellent heat resistance and solubility in a fluorine-based solvent. A perfluoropolyether compound in accordance with an aspect of the present invention has, in hydrocarbon groups at both terminals thereof, five or six hydroxyl groups in total.

A method for producing a renewable base oil from a feedstock of biological origin includes providing a feedstock, the feedstock including: 2-95 wt % of a mixture of free fatty acids; 5-98 wt % fatty acid glycerols selected from mono-glycerides, di-glycerides and tri-glycerides of fatty acids; 0-50 wt % of one or more compounds selected from the list consisting of: fatty acid esters of the non-glycerol type, fatty amides and fatty alcohols; a major part of the feedstock being a mixture of free fatty acids and fatty acid glycerols; subjecting all or part of the feedstock to ketonisation reaction conditions where two free fatty acids react to yield a ketone stream, and subjecting the ketone stream to both hydrodeoxygenation and to hydroisomerisation reaction conditions, to yield a deoxygenated and isomerised base oil product stream containing the renewable base oil.

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.

The present invention relates to an alphaolefin oligomer having a uniform structure and a method of preparing the same, in which the alphaolefin oligomer has a uniform molecular structure with a low branch ratio, thereby exhibiting improved thermal and oxidative stability, a long service life, low volatility, a low pour point and a high viscosity index.

A C.sub.31 renewable base oil is disclosed that is suitable as a base oil to provide low viscosity base oils, such as having both low Noack volatility and low CCS-30° C. viscosity and/or to provide low viscosity base oils at the same time having a combination of acceptable HTHS and KV100 to allow the industry's base oil blenders to formulate high quality engine oils, such as SAE grade 0W-20, 0W-16, 0W-12 or 0W-8.

A number of different branched hydrocarbon compounds (formula I) having a star-like configuration (S) are prepared from renewable oils containing fatty acids or derivatives containing fatty acids. The branched hydrocarbon compounds may be isolated individually or in mixtures, and may be used as part of base oils, such as renewable base oils (RBOs). A process for preparing the branched hydrocarbon compounds of formula I involve conditions that favour a trimerisation reaction followed by hydrotreating conditions. The compounds of formula I may be made by catalytically treating renewable material in a process, and the compounds have desirable qualities relating to lubrication, cold flow as well as having a low Noack volatility.

Hydrotreatment of biological oil is disclosed for producing renewable base oil and a diesel oil from low value biological oils. Low value biological oils containing free fatty acids and fatty acid esters can be processed into a renewable base oil and a renewable diesel oil in an efficient manner by first separating at least part of the free fatty acids from the feedstock and then processing separately this free acid feed in a ketonisation reaction followed by hydrodeoxygenation and hydroisomerisation reactions to yield a renewable base oil stream. The remaining free fatty acid depleted feed is processed in a separate hydrodeoxygenation and hydroisomerisation step to yield a renewable diesel stream.

A lubricating composition comprises an amide and at least one additive. The amide is the reaction product of a secondary, branched amine and a carboxylic acid. The carboxylic acid may be a monocarboxylic acid or a dicarboxylic acid, including dimer acid. The amide is hydrolytically stable, and may be used to increase the hydrolytic stability of the lubricant composition. Alternatively, the amide may be used to increase the additive solubility or detergency of the lubricant composition.

Methods are disclosed for producing renewable base oil and a diesel oil from low-value biological oils. Low-value biological oils containing free fatty acids and fatty acid esters can be processed into a renewable base oil and a renewable diesel oil by first separating at least part of the saturated free fatty acids from the feedstock and then processing separately this saturated free acid feed in a ketonisation reaction followed by hydrodeoxygenation and hydroisomerisation reactions to yield a renewable base oil stream. The remaining free fatty acid depleted feed may be processed in a separate hydrodeoxygenation and hydroisomerisation step to yield a renewable diesel stream.