Patent GB-854948-A (GB)
Title: Improved lubricants
IPC: C10M169/00
Filed: 1957-06-28
Abstract: A paraffin wax fraction containing at least 80% by weight of paraffin hydrocarbons having 21-32 carbon atoms per molecule and a melting point of 120-150 DEG F. is irradiated with high energy ionizing radiations such that the said fraction receives at least 104 ergs/gm./sec. for a time sufficient to convert 75% of the fraction to a rubbery oil-soluble material.  A preferred product having a boiling point above 950 DEG F. and a melting point of 400-700 DEG F. may be separated from the reaction product.  The paraffin waxes employed preferably have a boiling point of 735-840 DEG F. and contain more than 70% straight chain paraffins, less than 20% branched chain paraffins and less than 10% naphthene or saturated cyclic compounds. Sources of radiation may be particle accelerators, spent fuel elements, and radioactive elements such as Co60, the preferred gamma ray flux from such materials being greater than 105 Roentgens/hr. Nuclear reactors may also be used as the radiation source, the average gamma ray flux then being above 105 Roentgens/hr. and the average neutron flux above 1010 neutrons/cm2/sec.  The radiation is preferably carried out in the liquid phase, e.g. at 10-100 p.s.i. and at 0-900 DEG F., preferably below 700 DEG F., and the liquid may be passed in pipes disposed in, around or near the fissionable material. Moderators such as carbon and water may be used.  During irradiation, porous, solid inert material such as catalysts and/or absorbents, e.g.  Kieselguhr, carbon or coke, cracking and dehydrogenation catalysts may be present in the form of fixed or moving beds.  In the examples, a silica-alumina catalyst and a platinum on alumina catalyst containing also chlorine are used.  They may be regenerated by burning or reworking.  Materials giving off secondary radiation such as B10, Li6, Cd113 and Be9 may also be present, as pure or concentrated isotopes or as natural elements containing these isotopes; they may be carried on the above mentioned solids or used as such or in solution (e.g. tri-n-dodecyl borate may be used). After irradiation the mixture may be filtered, distilled or subjected to absorption, adsorption, extraction, crystallisation or ion exchange and may be partly recycled.  Specification 802,552 is referred to.ALSO:A paraffin wax fraction containing at least 80% by weight of paraffin hydrocarbons having 21-32 carbon atoms per molecule and a melting point of 120-150 DEG F. is irradiated with high energy ionising radiations such that the said fraction receives at least 104 ergs/gm./sec. for a time sufficient to convert 75% of the fraction to a rubbery oil-soluble material, suitable for use as a lubricant additive to improve the viscosity index, shear stability and pour point.  A preferred product having a boiling point above 950 DEG F. and a melting point of 400-700 DEG F. may be separated from the reaction product.  A suitable lubricating oil base stock may have a viscosity of 40-300 S.S.U. at 210 DEG F. and a boiling point of 700-1200 DEG F.; the additive preferably comprises less than 4% wt. of the composition.  The final composition may have similar properties and also a viscosity index above 100 and a pour point below 10 DEG F.  The product of the invention may also be used in oils with a viscosity index of 50-70.  Suitable base stocks may be of animal, vegetable, mineral or synthetic (e.g. di-2-ethyl-hexyl-sebacate) origin.  The paraffin waxes employed preferably have a boiling point of 735-840 DEG F. and contain more than 70% straight chain paraffins, less than 20% branched chain paraffins and less than 10% naphthene or saturated cyclic compounds. The compositions may also contain detergents (barium octyl phenol sulphide) oxidation inhibitors (phenylalpha-naphthylamine), corrosion inhibitors (zinc dihexyl dithiophosphate), viscosity index improvers (polyisobutylene) rust inhibitors, and antifoaming agents in minor proportions. Lubricating grease compositions may contain conventional grease thickeners (calcium stearate), soap-salt complex thickeners (calcium acetate-calcium stearate), inorganic thickeners (silica, carbon), polyethylene, polybutene, oxidation inhibitors and corrosion inhibitors in minor proportions.  Sources of radiations may be particle accelerators, spent fuel elements, and radioactive elements such as Co60, the preferred gamma ray flux from such materials being greater than 105 Roentgens/hr. Nuclear reactors may also be used as the radiation source, the average gamma ray flux then being above 105 Roentgens/hr. and the average neutron flux above 1010 neutrons/cm2/sec.  The radiation is preferably carried out in the liquid phase, e.g. at 10-100 p.s.i. and at 0-900 DEG F., preferably below 700 DEG F., and the liquid may be passed in pipes disposed in, around or near the fissionable material.  Moderators such as carbon and water may be used.  During irradiation, porous, solid inert material such as catalysts and/or absorbents, e.g. Kieselguhr, carbon or coke, cracking and dehydrogenation catalysts may be present in the form of fixed or moving beds.  In the examples, a silica-alumina catalyst and a platinum on alumina catalyst containing also chlorine are used.  They may be regenerated by burning or reworking. Materials giving off secondary radiation such as B10, Li6, Cd113 and Be9 may also be present, as pure or concentrated isotopes or as natural elements containing these isotopes; they may be carried on the above mentioned solids or used as such or in solution (e.g. tri-n-dodecyl borate may be used).  After irradiation the mixture may be filtered, distilled or subjected to absorption, adsorption, extraction, crystallisation or ion exchange and may be partly recycled.  Specification 802,552 is referred to.