Patent GB-700319-A (GB)
Title: Improvements in or relating to stabilized lubricating oil additives
IPC: C10M159/12
Filed: 1951-04-18
Abstract: Sulphur-containing additives for lubricating oils are treated to inhibit the evolution of sulphur-containing gases, such as hydrogen sulphide, by heating them with from 1 to 5 per cent. by weight of an amido-imido derivative of a carboxylic acid or a salt or substitution product thereof. particularly guanidine, substituted guanidines and guanidine salts such as the carbonate. The substituted guanidines may contain hydrocarbon groups with 1 to 20 carbon atoms and examples of alkyl, cycloalkyl, aryl and alkaryl substituents are given.  Of the substituted guanidines it is preferred to use the symmetrical tin-compounds, preferably with alkyl or cycloalkyl substituents, including the tri-naphthenyl and triaralkyl guanidines.  Biguanide, dicyandiamide and dicyandiamidine may also be used. Sulphur-containing additives which may be treated include terpenes, esters, phenols and their derivatives, olefins and halogenated hydrocarbons such as chlorinated wax, all of which have been sulphurized, with or without subsequent treatment with phosphorus sulphides.  Organic thiophosphates, mercaptan derivatives and organic sulphides and polysulphides, including phenol sulphides and their salts, xanthates, carbonates, and thiophosphates, as well as metal-containing alkyl phenol sulphides, may also be treated.  In an example a phosphorus-pentasulphide-treated barium salt of iso-butyl phenol sulphide is treated with 2.5 per cent. guanidine carbonate, as a 50 per cent. aqueous solution, by heating and stirring at 250-270 DEG F. for 1 hour.ALSO:Sulphur-containing additions for lubricating oils are treated to inhibit the evolution of sulphur-containing gases, such as hydrogen sulphide, by heating them with from 1 to 5 per cent. by weight of an amido-imido derivative of a carboxylic acid or a salt or substitution product thereof, particularly guanidine, substituted guanidines and guanidine salts such as the carbonate. The substituted guanidines may contain hydrocarbon groups with 1 p  to 20 carbon atoms and examples of alkyl, cycloalkyl, aryl and alkanyl substituents are given.  Of the substituted guanidines it is preferred to use the symmetrical tri-compounds, preferably with alkyl or cycloalkyl substituents, including the trinaphthenyl and triaralkyl guanidines.  Biguanide, dicyandiamide and dicyandiamidine may also be used. Sulphur-containing additives which may be treated include fatty materials such as sperm oil, lard oil and fatty acids, terpenes, esters, phenols and their derivatives, olefins, and halogenated hydrocarbons such as chlorinated wax, all of which have been sulphurized, with or without subsequent treatment with phosphorus sulphides.  Organic thiophosphates, mercaptan derivatives and organic sulphides and polysulphides, including phenol sulphides and their salts, xanthates, carbonates, and thiophosphates, as well as metal-containing alkyl phenol sulphides, may also be treated.  The additives may be incorporated into lubricating oils and greases, especially mineral base oil, in proportions from 0.01 to 10 per cent. or more by weight, and they may act as extreme pressure agents, oxidation inhibitors, detergents, metal deactivators or corrosion inhibitors.  In an example, sulphurized sperm oil containing 6 per cent. sulphur and subsequently treated with 0.5 per cent. P4S3 at 215 DEG  F. is treated with 2.5 per cent. guanidine carbonate, as a 50 per cent. aqueous solution, at 210 DEG  to 220 DEG F. the mixture being maintained at 250 DEG  F. for 2 hours to evaporate the water.