Patent GB-808130-A (GB)
Title: Complex calcium salts of oxidised petroleum oils
IPC: C07C51/41
Filed: 1955-12-29
Abstract: Mineral lubricating oils comprise, as a detergent additive, a minor amount of an oil solution of a complex calcium salt of an oxidized petroleum oil, which solution is prepared by a process according to any of the claims of the parent Specification wherein calcium hydroxide is used as the metal hydroxide, with the modification that in steps 3, 4 and 5 the calcium hydroxide is replaced either wholly by calcium hypochlorite or wholly or in part, but at least to the extent of about 25 per cent by weight, by calcium chloride.  Examples describe complex calcium salts in oil solution prepared by heating a mid-continent bright stock with about 20 per cent Ca(OH)2 at about 375 DEG  F. while passing air therethrough and then filtering the product, cooling the filtrate and mixing it with aqueous calcium chloride or hypochlorite and toluene as a diluent, then heating to remove water and the diluent and filtering; alternatively, the unfiltered oxidation reaction product is cooled, aqueous calcium chloride added thereto and the mixture dehydrated and filtered.  In a comparative experiment, the unfiltered oxidation product is cooled, mixed with water, dehydrated and filtered and yields an oil solution having a lower calcium content.  The detergent properties are composed of lubricating mineral oils containing minor amounts of the finished oil solutions of the invention, the oil solution obtained at the end of the oxidation step and the product of the comparative experiment.ALSO:The invention comprises complex calcium salts of oxidized petroleum oil in oil solution prepared by a process according to any of the claims of the parent Specification wherein calcium hydroxide is used in the process as the metal hydroxide, with the modification that in steps 3, 4 and 5 the calcium hydroxide is replaced either wholly by calcium hypochlorite or wholly or in part, but at least to the extent of about 25 per cent by weight, by calcium chloride; as a result, the calcium content of the product is greater than when calcium hydroxide alone is used in steps 3, 4 and 5.  When the water-complexing reaction (steps 3 and 4) is to be effected using only calcium chloride or calcium hypochlorite, the reaction mixture from the oxidation step is separated from unreacted calcium hydroxide, cooled to below the B.P. of water and then the calcium chloride or hypochlorite is added, generally as an aqueous solution. When both calcium hydroxide and calcium chloride are to be used, then the oxidation reaction product mixture containing unchanged calcium hydroxide is cooled and water and calcium chloride added thereto or the oxidation reaction product mixture is filtered and cooled and then water, calcium chloride and calcium hydroxide are added to the filtrate.  In typical examples: (1) a mixture of a refined midcontinent bright stock and 20 per cent of calcium hydroxide are heated at about 375 DEG  F. while air is passed therethrough; the product is then filtered, cooled, mixed with toluene or diluent and aqueous calcium chloride, heated while aerating with nitrogen gas to remove the diluent and water and is then filtered; (2) the oil stock of (1) is similarly oxidized in the presence of calcium hydroxide, the product is cooled, aqueous calcium chloride is added directly and the mixture is then reacted as in (1); a comparative experiment wherein only water is added yields a product with a lower final calcium content; (5) the oxidation step of (1) is repeated in substantially the same manner, the product is filtered and mixed with toluene and aqueous calcium hypochlorite and after being refluxed is worked up as before.  The oil solutions of complex calcium salts are detergent additives for lubricating oils (see Group III).