Patent GB-782054-A (GB)
Title: Improvements in or relating to processes for preparing lubricating compositions
Inventor: AGIUS PETER JOSEPH VERMONT JAM
IPC: C10M135/04
Filed: 1954-09-03
Abstract: Mineral lubricating oil compositions are prepared by sulphurizing a substantially paraffinic mineral oil or oil-soluble copolymerized olefinic hydrocarbons with elementary sulphur or a metal-containing sulphurizing agent, e.g. germanium or antimony sulphide, wholly or in part at a temperature between 180 DEG  C. and the cracking temperature of the hydrocarbon reagent, for a period of time sufficient to cause a proportion of the combined sulphur of the hydrocarbon thereby sulphurized to be lost whereby a product is obtained which imparts detergent properties to lubricating oils, and blending the product with a mineral oil. Specified hydrocarbon reagents are paraffin oil distillates having a viscosity of at least 150 s.u.s. at 210 DEG  F., copolymers of butene, isobutene, butadiene, styrene, divinyl benzene or isoprene and, especially, degraded butyl rubber.  Sulphurization may be effected at 180-290 DEG C. with sulphur and preferably at 270-290 DEG  C. with a metal-containing sulphurizing agent. Sulphurization catalysts may be present.  In example: (1) a substantially paraffinic brightstock is heated with 10 per cent sulphur at 210-230 DEG  C. for 5-14 hours, or in comparative experiments, at 120-170 DEG  C., and the product is filtered and blended (5 per cent) in an S.A.E.30 grade mineral oil and the blends are compared for detersive properties; (2) as in (1) but sulphurization is effected with antimony sulphide at 180-270 DEG C. for 24 hours; (3) a degraded butyl rubber M.W. 6000 is heated with sulphur for 9 hours at 250 DEG  C. and a blend of the product is formed as in (1).  Graphs show the relationship between time and amount of combined sulphur in the products of sulphurization at temperatures above and below 180 DEG  C.  According to the Provisional Specification, any hydrocarbon may be used in the reaction. Specification 722,681 is referred to.ALSO:Sulphurized hydrocarbons for use as detergent additives in lubricating oils (see Group III) are prepared by sulphurizing a substantially paraffinic mineral oil or oil-soluble copolymerized olefinic hydrocarbons with elementary sulphur or a metal-containing sulphurizing agent such as antimony or germanium sulphide, wholly or in part at a temperature between 180 DEG  C. and the cracking temperature of the hydrocarbon reagent, for a period of time sufficient to cause a proportion of the combined sulphur of the hydrocarbon thereby sulphurized to be lost whereby a product is obtained which imparts detergent properties to lubricating oils.  Specified hydrocarbon reagents are paraffinic oil distillates having a viscosity of at least 150 S.U.S. at 212 DEG  F., copolymers of butene, isobutene, butadiene, styrene, divinyl benzene or isoprene and especially degraded butyl rubber (see Group V).  The copolymers should preferably have a M.W. of 300-25,000. Sulphurization with sulphur may be effected at 180-290 DEG  C. and with metal-containing sulphurizing agents, preferably between 270-290 DEG  C.; lower temperatures, e.g. 170 DEG  C., may be used in the early stages.  Sulphurization catalysts such as tetramethyl thiuram disulphide, mercapto benzthiazole and diphenyl-guanidine may be present.  In examples: (1) a substantially paraffinic bright stock is heated with 10 per cent of sulphur in the presence or absence of some of the above-mentioned catalysts at 210-230 DEG  C. for 5-14 hours; comparative experiments are described using temperatures of 120-170 DEG  C., the products being shown to be much less detersive; (2) the brightstock of (1) is heated with 10 per cent antimony sulphide for 24 hours at 180 DEG  C. to 270 DEG  C.  Graphs show the relationship between time and the amount of combined sulphur in the product for some sulphurizations effected at temperatures above and below 180 DEG C.  According to the Provisional Specification, any hydrocarbon may be used in the reaction. Specification 722,681 is referred to.ALSO:Degraded butyl rubber, preferably of M.W. between 300 and 25,000 is sulphurised with elementary sulphur or a metal-containing sulphurizing agent such as antimony or germanium sulphide, wholly or in part at a temperature between 180 DEG C. and the cracking temperature of the rubber for a period of time sufficient to cause a proportion of the combined sulphurs of the rubber thereby sulphurized to be lost whereby a product is obtained which imparts detergent properties to lubricating oils (see Group III).  In an example, a butyl rubber M.W. 40,000 is degraded to M.W. 6000 in a mill and sulphurized with sulphur at 250 DEG C. for 9 hours.  Specification 722,681 [Group IV(b)] is referred to.