Patent GB-758556-A (GB)
Title: Mineral oil compositions and additives for use therein
IPC: C10M159/18
Filed: 1954-04-06
Abstract: The invention comprises a mineral oil-soluble reaction product obtainable by passing substantially anhydrous carbon dioxide into a substantially anhydrous solution, in a mineral oil, of the barium salt of a 2 : 4-dialkyl-phenol in which the alkyl groups each contain from 5 to 10 carbon atoms, and mineral or synthetic lubricating oil compositions containing the same (see Group III). The mineral lubricating oil compositions may also contain the mineral oil-soluble product obtainable by passing substantially anhydrous carbon dioxide into a solution, in a mineral oil, of a basic barium salt of an alkyl-substituted aryl sulphonic acid having at least one but not more than four long chain alkyl groups having at least eight carbon atoms in each group.  The barium 2 : 4-dialkyl phenates are prepared by neutralizing a 2 : 4-dialkyl phenol with an oxide, hydroxide or alcoholate of barium, or by reaction between a water-soluble metal salt and an alkali metal 2 : 4-dialkyl phenate.  The solution of barium 2 : 4-dialkyl phenate in mineral oil is heated to between 20 DEG  and 200 DEG  C. while the carbon dioxide is passed, about one molecule of carbon dioxide being absorbed per atom of barium.  In examples (1) 2 : 4-di-(branched chain nonyl)-phenol is dissolved in a motor oil, a solution of barium oxide in methanol is added, the mixture is heated to remove methanol and complete the reaction, then the mixture is filtered and anhydrous carbon dioxide is bubbled under reduced pressure into the heated solution, which is finally filtered; (2)-(5) the carbonated products from barium 2 : 4-di-(1 : 1 : 3 : 3-tetramethyl - butyl) -, - (1 : 3 : 5 - trimethylhexyl) -, - (tertiary amyl) - and - (2 - ethyl - hexyl) - phenate are prepared as in (1).  Other specified phenates which may be treated as in Example (1) are barium 2 : 4 - di - (sec. - amyl) -, - (isoamyl) -, - (1 : 3 - dimethyl - butyl) - and - (1-methyl - heptyl) - phenate.  The basic barium salts of alkyl-substituted aryl sulphonic acids are prepared by first reacting an alkyl halide having more than eight carbon atoms with an aromatic hydrocarbon such as benzene, toluene, xylene, ethyl- or isobutyl- or tertiary butylbenzene, cumene, cymene, diphenyl, indene and naphthalene in a proportion to give one to four alkyl groups in the aromatic nucleus.  The alkyl-substituted aryl compound is sulphonated, the corresponding basic barium compound prepared and then carbonated in a manner similar to that for the barium 2 : 4-dialkyl phenate except that water is liberated during the carbonation and is removed.  Thus, a paraffin wax having an average of twenty-three carbon atoms in the molecule, is chlorinated and the product condensed with benzene using aluminium chloride as catalyst to give a dialkyl derivative which is sulphonated with oleum.  The sulphonation mixture is dissolved in a mineral oil, washed with water, the oil layer being then reacted with barium hydroxide, dehydrated and filtered.  The filtrate is heated, carbon dioxide is passed in under reduced pressure, water is removed and the mixture finally filtered.  2 : 4 - dialkyl phenols are prepared by alkylating phenol with olefins (many specified) in the presence of sulphuric acid.ALSO:Lubricating compositions comprise a mineral or synthetic lubricating oil having dissolved therein the reaction product obtainable by passing substantially anhydrous carbon dioxide into a substantially anhydrous solution in a mineral oil, of the barium salt of a 2:4-dialkyl-phenol in which the alkyl group each contain from five to ten carbon atoms (see Group IV(b)).  The composition may also contain the oil-soluble reaction product obtainable by passing substantially anhydrous carbon dioxide into a mineral oil solution of a basic barium salt of an alkyl substituted aryl sulphonic acid having at least one but not more than four long chain alkyl groups having at least eight carbon atoms in each group (see Group IV(b)). The preferred amount of both the above ingredients is from 0.1-10.0 per cent by weight.  The compositions may contain from 0.1-3.0 per cent by weight of an oil soluble phosphorized- and sulphurizeddicylic terpene.  Other agents which may be added to the compositions are dyes, pour point depressants, soaps, corrosion inhibitors, antioxidants such as the zinc salts of dialky thiophosphoric acids and sulphurized phenols, thickeners, viscosity index improvers, defoamants, resins and graphite.