GB476984A - A process for producing lubricating oils, insulating oils and similar viscous oils - Google Patents

Abstract

The oxidation stability of viscous synthetic hydrocarbon oils for use, e.g. as lubricants or insulating oils, is increased by adding thereto extracts obtained from natural hydrocarbon oils boiling above about 300 DEG C., or fractions thereof, by the use of selective solvents, which extracts have been refined by selective hydrogenation. The synthetic hydrocarbons are products obtained from unsaturated or aromatic hydrocarbons by polymerization or condensation, e.g. by the polymerization of vapour phase cracked products of paraffin wax or paraffinous materials, or by the condensation of olefines or chloroparaffins with aromatic hydrocarbons. The polymerization or condensation may be effected either chemically in the presence of aluminium chloride, boron p fluoride or a similar agent, or by voltolization. The extracts are obtained, preferably from a heavy mineral oil fraction, by selective solvents for constituents other than paraffins, such as liquid sulphur dioxide, nitrobenzene furfurol or cresol, and are refined to remove olefines and sulphur, nitrogen and oxygen compounds, or to render them innocuous, by selective hydrogenation. In examples, 5 per cent of an Edeleanu extract of a lubricating oil, which extract has been refined by selective hydrogenation at a temperature of 400 DEG C. and at an initial hydrogen pressure of 100 atmospheres in the presence of a molybdenum catalyst, is added to a synthetic lubricating oil obtained by polymerizing a vapour phase cracked gasoline, or a cracked distillate obtained from a hydrocarbon material rich in paraffin was, in the presence of aluminium chloride.