Patent GB-804307-A (GB)
Title: Improved processes for preparing lubricating compositions
Inventor: AGIUS PETER JOSEPH VERMONT JAM
IPC: C10M135/04
Filed: 1957-01-08
Abstract: Lubricating oil compositions comprise a mineral lubricating oil and a detergent additive prepared by a modification of the process described in the parent Specification for sulphurizing hydrocarbons in which either (a) a cracked wax bottoms fraction is sulphurized wholly or in part at a temperature above 175 DEG  C. but below the cracking temperature and the product maintained at this temperature for a period of time sufficient to cause a proportion of the combined sulphur to be lost; or (b) an olefine polymer is sulphurized at a temperature below the cracking temperature and the product maintained at not less than 290 DEG  C. for a period of time sufficient to cause a proportion of the combined sulphur to be lost.  The olefine polymer should be oilsoluble and preferably has a molecular weight between 1000 and 10,000.  The preferred polymer is polybutene.  In examples the 40 per cent bottoms of a cracked wax, "Fyrax" (Registered Trade Mark) is sulphurized with elemental sulphur at 175 DEG  C. for times of 100 to 330 minutes and polybutene (M.W. 2036) is sulphurized with elemental sulphur at 200 DEG  C., the temperature being raised to 230 DEG  C. after 180 minutes and to 300 DEG  C. after another 200 minutes, this latter temperature being maintained for a further 220 minutes.  The detergency properties produced by the products when added in a proportion of 5 per cent wt. to an S.A.E. 30 mineral lubricating oil are compared with those produced by the corresponding products sulphurized below the respective critical temperatures (175 DEG  and 290 DEG  C.).ALSO:In a modification of the process described in the parent Specification, wherein oil-soluble copolymerized olefinic hydrocarbons are sulphurized with elemental sulphur or a metal-containing sulphurizing agent wholly or in part at a temperature between 180 DEG  C. and the cracking temperature of the hydrocarbon and maintained at this temperature for sufficient time to cause a proportion of the combined sulphur of the hydrocarbon thereby sulphurized to be lost-an olefine polymer is sulphurized at a temperature below the cracking temperature and maintained at not less than 290 DEG  C. for a period of time sufficient for some of the combined sulphur to be lost.  Polymers mentioned are oil-soluble and have molecular weights between 1,000 and 10,000.  In an example, polybutene (M.W. 2036) is sulphurized with elemental sulphur at 200 DEG  C., the temperature being raised to 230 DEG  C. after 180 minutes and to 300 DEG  C. after another 200 minutes, this latter temperature being maintained for a further 220 minutes.  The products are used as detergent additives in mineral oils (see Group III).ALSO:In a modification of the process described in the parent Specification for sulphurizing hydrocarbons a cracked wax bottoms fraction is sulphurized wholly or in part at a temperature above 175 DEG  C. but below the cracking temperature and the product maintained at this temperature for a period of time sufficient to cause a proportion of the combined sulphur to be lost.  In an example the 40 per cent bottoms of a cracked wax, "Fyrax" (Registered Trade Mark) is sulphurized with elemental sulphur at 175 DEG  C. for times of 100 to 330 minutes.  The products are used as detergent additives in mineral lubricating oils.