Patent GB-748694-A (GB)
Title: Improvements in or relating to lubricating compositions and additives therefor
Inventor: ELLIOTT JOHN SCOTCHFORD
IPC: C10M135/02
Filed: 1952-07-03
Abstract: The invention comprises an additive for lubricating oils (see Group III), said additive being a compound obtained by the sulphurization or sulphurization and phosphorization of the unsaponifiable matter extracted from saponified wool grease, or a metal salt of such a sulphurized and phosphorized compound.  The unsaponifiable matter may be sulphurized by heating with sulphur and the reaction may be assisted by adding a small amount of sulphur monochloride or sulphur dichloride.  The sulphurized product may then be phosphorized by reacting it with a phosphorus compound, e.g. a phosphorus sulphide or halide and particularly phosphorus pentasulphide or sesquisulphide, e.g. by heating with either of the latter at 220 DEG  to 250 DEG  F. Alternatively, the unsaponifiable matter may be reacted with sulphur chlorides in oil or an inert solvent and the chlorine then replaced by sulphur, or phosphorus and sulphur, by reacting the product in a suitable solvent with sodium sulphide or polysulphide or the sodium salt of an organic dithiophosphoric acid.  The sulphurization of the unsaponifiable material may be carried out in the presence of a vulcanization accelerator, e.g. mercaptobenzothiazole, benzothiazole disulphide, tetramethyl and tetraethyl thiuram disulphides or mixtures of these compounds with diphenyl guanidine.  It is preferred to carry out the sulphurization in the presence of an aliphatic, alicyclic, or reduced heterocyclic secondary amine such as dicyclohexylamine, diethanolamine, or morpholine and the sulphurization is facilitated by carrying it out in the presence of mineral oil.  The products may be freed from oil-insoluble impurities by dissolving in a suitable solvent such as petroleum ether, filtering, and then removing the solvent by distillation. Alternatively, the phosphorized - sulphurized reaction products may be heated in oil solution with a minor amount of an aqueous suspension of lime or baryta and then filtered with the addition of filter-aid material.  The metal salts can be prepared by reacting the unsaponifiable matter with a phosphorus sulphide, preferably the sesquisulphide, and then neutralizing the resulting acidic products with an alkali or alkaline earth metal oxide or hydroxide.  The zinc and magnesium salts are referred to.  In a further form of the invention mixed products may be obtained by reacting with a phosphorus sulphide a mixture of the unsaponifiable matter and another organic compound capable of reacting with the phosphorus sulphide, e.g. an alcohol or phenol, and these products may be converted into a metal salt as above.  Alternatively the phosphorized sulphurized unsaponifiable matter, or metal salts thereof, may be mixed with other organic compounds capable of forming metal derivatives and the mixture then converted to the metal derivatives as above. Examples of suitable organic compounds are dithiophosphoric acids, phenols, and phenolthioethers.  The additives may be purified and bleached, e.g. by treatment with fuller's earth.  The unsaponifiable matter is preferably that known under the Registered Trade Mark "Varwolax" which may be prepared by the process described in Specification 553,322 or it may be the mixture of wool wax alcohols and sterols sold under the Registered Trade Mark "Hartolan." In examples: (1) "Varwolax" is sulphurized by heating with sulphur monochloride at 230 DEG  F. in the presence of a light mineral oil followed by the addition of sulphur and further heating at about 380 DEG  F. for three hours; (2) the product of (1) is heated with phosphorus pentasulphide at 230 DEG  to 270 DEG  F. for 8 hours and the resulting product mixed with light mineral oil and the mixture warmed and filtered with the addition of a filter aid; (3) "Varwolax" is dissolved in mineral oil and stirred with a mixture of sulphur, mercaptobenzothiazole and diphenyl guanidine for 5 hours at 350 DEG F., a filter aid is then added and the material filtered; (4) a mixture of "Varwolax," mineral oil, sulphur and dicyclohexylamine is heated at 330 DEG  F., the product cooled to 240 DEG  C. and reacted with phosphorus sesquisulphide.  Mineral oil is then added and the mixture cooled and then heated with a suspension of slaked lime in water and the product filtered; (5) as in (4) except that a mixture of wool wax alcohols sold under the Registered Trade Mark "Hartolan" is used instead of "Varwolax"; (6) "Varwolax" is reacted with sulphur dichloride in benzene solution and the viscous liquid product remaining after distilling off the benzene is dissolved in benzene and the solution treated with a solution of sodium sulphide and sulphur in alcohol, filtered, freed of solvent, the residue dissolved in petroleum ether and the solution filtered and freed of solvent to yield a dark brown stiff grease-like material; (7) "Varwolax" is reacted with phosphorus sesquisulphide at about 240 DEG  F., mineral oil is then added and the mixture heated with barium hydroxide and filtered with the addition of filter aid material to yield the metal derivative; (8) as in (7) except that an aqueous slurry of zinc oxide is used instead of barium hydroxide; (9) a product obtained as in (7) is heated with p-octyl phenol and the product reacted with barium hydroxide and then filtered to yield a product having an increased barium content; (10) as in (9) except that cresylic acid is used instead of p-octyl phenol.  Specification 670,077 also is referred to.ALSO:A lubricating composition comprises a lubricating oil base in which is incorporated up to 10 per cent by weight of a compound obtained by the sulphurization or sulphurization and phosphorization of the unsaponifiable matter obtained from saponified wool grease, or a metal salt of such a sulphurized and phosphorized compound (see Group IV(b)).  The lubricating oil base may be a mineral lubricating oil or a synthetic lubricating oil which may be of the di-ester type or the polyether type. Other additives may be present e.g. halogenated organic compounds such as chlorinated paraffin wax, sulphur-containing compounds e.g. dibenzyl sulphide, di(3-carbonethoxy-4-hydroxyphenyl) disulphide and sulphurized terpenes, e.g. sulphurized a -pinene, detergent additives such as metal petroleum (mahogany) sulphonates, e.g. calcium, tin or basic barium petroleum sulphonate; metal salts of organic dithiophosphoric acids, metal salts of alkylated phenols and phenol thioethers, phosphate and phosphite esters, e.g. tricresyl phosphate, and viscosity index improvers, pour point depressants, and foam inhibitors.  Specified types of base oils are extreme pressure oils, internal combustion engine oils, storage oils, slushing compositions, rust-preventative compositions, cutting and soluble oils, and hydraulic oils.  The unsaponifiable matter may be sulphurized by heating with sulphur and the reaction may be assisted by adding a small amount of sulphur monochloride or dichloride.  The sulphurised product may then be phosphorized by reacting it with a phosphorous compound such as phosphorous pentasulphide or sesquisulphide. Alternatively, the unsaponifiable matter may be reacted with sulphur chlorides in oil or an inert solvent and the chlorine then replaced by sulphur, or phosphorous and sulphur, by reacting the product in a suitable solvent with sodium sulphide or polysulphide or the sodium salt of an organic dithiophosphoric acid.  The sulphurization of the unsaponifiable matter may be carried out in the presence of a vulcanization accelerator or in the presence of an aliphatic, alicyclic, or reduced heterocyclic secondary amine.  The products may be freed from oil-insoluble impurities by dissolving in a suitable solvent such as petroleum ether, filtering, and then removing the solvent by distillation. Alternatively, the phosphorized-sulphurized reaction products may be heated in oil solution with a minor amount of an aqueous suspension of lime or baryta and then filtered with the addition of filteraid material.  The metal salts can be prepared by reacting the unsaponifiable matter with a phosphorous sulphide, preferably the sesquisulphide, and then neutralizing the acidic products with an alkali or alkalie earth metal oxide or hydroxide. The zinc and magesium salts are referred to.  The additives may also comprise mixed products obtained by reacting with a phosphorous sulphide a mixture of the unsaponifiable matter and another organic compound capable of reacting with the phosphorous sulphide, e.g. an alcohol or phenol and these products may be converted into their metal salts as above. Alternatively, the phosphorized-sulphurized unsaponifiable matter, or metal salts thereof, may be mixed with other organic compounds capable of forming metal derivatives and the mixture then converted to the metal derivatives as above.  Specified organic compounds are dithiophosphoric acids, phenols, and phenolthioethers.  The unsaponifiable matter is preferably that known under the registered trade mark "Varwolax" which may be prepared by the process described in Specification 553,322 or it may be the mixture of wool wax alcohols and sterols sold under the registered trade mark "Hartolan."  Examples are given to show the effect of adding the various types of additives derived from "Varwolax" and "Hartolan" with or without other known additives to extreme pressure lubricants and internal combustion engine oils and also to show their value as rust inhibitors in oil compositions.  Specification 670,077 is also referred to.