| 摘要 |
Lubricating-oil is obtained from a hydrocarbon oil fraction at least 95% of which boils above 285 DEG C. and containing condensed ring naphthenes by contacting the oil with a hydrogenation catalyst on a non-acidic support in the presence of hydrogen to convert the condensed ring naphthenes to aromatic compounds, and separating aromatic compounds from the non-aromatic compounds which are recovered for use as lubricating oil. Any olefines present in the oil will have been hydrogenated, while monocyclic naphthenes are unchanged. Preferably the oil is first hydrodesulphurized, deasphalted and dewaxed. The catalyst may be a platinum group metal, preferably platinum or palladium, nickel, cobalt, molybdenum or tungsten supported on alumina, silica, zirconia, magnesia, clays, kieselguhr, silica-alumina, or silica-magnesia which if acidic or not catalytically inert is treated with steam, alkali carbonate, hot water or ammonia or composited with alkali or alkaline-earth metal oxide, an amine or ammonia, or supported on carbon. Conditions may be 260-480 DEG C. and subatmospheric to 10 atmospheres pressure. Separation of aromatic hydrocarbons may be effected by solvent extraction with glycols, methanol, aldehydes, nitriles, dinitriles, or amines, by adsorption on silica gel, activated charcoal or Attapulgus or other clay or by precipitation with trinitrotoluene or picric acid. |
