Patent GB-703631-A (GB)
Title: Sulphurised terpenes and lubricating compositions containing them
Inventor: MCLEAN DONALD HENRY
IPC: C10M135/04
Filed: 1950-12-08
Abstract: The reaction product obtained on treatment of terpenes with elemental sulphur in the presence of a rubber vulcanization accelerator is freed from by-products by treatment in the liquid phase with a solid absorbent.  Sulphurization is normally effected at 135-200 DEG C., preferably 170-180 DEG C., with 1.5 to 2 atoms of sulphur per mol. of terpene.  Preferably 5 per cent., e.g. 1-2 per cent. of accelerator is used and those specified are tetramethyl thiuriam disulphide, mercapto-benzothiazole and diphenyl guanidine.  Reaction times of 5-10 hours are quoted. Purification is preferably effected after steam distillation of the product.  The distillation is preferably effected at up to 120 DEG C.  Specified adsorbents are Florida Earth, Fuller's Earth, Montmorillonite clay, alumina, siliceous gels and charcoal. Earths are preferred and the adsorbents are preferably activated before use.  Less than 10 per cent. by volume of adsorbent, preferably 1-5 per cent., is normally used.  The time of treatment is usually less than 3 hours and preferably about 1/2 hour. The temperature is normally below 100 DEG C., e.g. 70 DEG C.  The product is used as a lubricating oil additive (see Group III).  In an example crude dipentene is treated with sulphur in the presence of mercaptobenzthiazole and diphenyl guanidines at 100-150 DEG C. (subsequently at 175 DEG C.), cooled to 100-110 DEG C., steam distilled and the residue treated with Fuller's Earth at 70 DEG C. Specifications 586,841, 688,293 and 697,461 are referred to.ALSO:A lubricating oil composition comprises a major proportion of a mineral lubricating oil and a minor proportion, preferably below 5 per cent., of the reaction product obtained by treating a terpene with elemental sulphur in the presence of a rubber vulcanisation accelerator which product is purified by treatment in the liquid phase with a solid adsorbent.  Specified absorbents are Florida and Fullers earth, Montmorillonite, clay, alumina, siliceous gels and charcoal.  Earths are preferred and the adsorbents are preferably activated before use. For details of the sulphurisation and purification (see Group IV (b)).  Preferably the reaction product is steam distilled before purification. Detergent additives may also be present in the composition. Representative of many such additives specified are calcium mahogany sulphonates, barium phenates, zinc butyl benzoate and metal organo- and thiophosphates.  Preferred additives are alkaline earth derivatives of alkyl phenol sulphides or sulphurized alkylated phenols (compare Specifications 586,841 and 697,461).  The preferred additives may be used in conjunction with calcium or barium mahogany sulphonates.  In a comparative experiment results are shown of engine tests on mineral oils containing 0.3 per cent. of sulphurised dipentene without clay treatment and 0.3 per cent. of sulphurized dipentene treated as in the invention with and without prior steam distillation.  The oils also contained 1.5 per cent. of barium p-ter. octyl phenol sulphide.  It is shown that the oil of the invention is less corrosive.  The finished product may be added to lubricating oils in amounts of 0.1-2 or 5 per cent., preferably 0.3-0.5 per cent. Detergent additives may be present in amounts of about 1-5 per cent., preferably about 1.5 to 2.5 per cent. Specification 688,293 also is referred to.