Document Type and Number:
Japanese Patent JPS4934723
Kind Code:
B1
Abstract:
A process for solvent refining lubricating oils comprises concurrently solvent refining at least two hydrocarbon lubricating oil fractions of different viscosities with a solvent effective preferentially to dissolve aromatic hydrocarbon components, for example furfural, in separate treating zones, separating the extract and raffinate phases from each zone, combining the raffinates and separating the solvent from the combined raffinates, solvent dewaxing the combined raffinate with a solvent effective preferentially to dissolve the oily components of said combined raffinate, for example a mixture of methyl ethyl ketone with benzene or toluene, under conditions effective to precipitate waxy components, separating the precipitated wax and separating dewaxing solvent from the dewaxed oil. The extracts may be combined, and the solvent recovered. The two starting fractions may be obtained by fractionating a hydrocarbon oil, solvent deasphalting the residual fraction, for example with propane, separating the precipitated asphalt from the solvent and deasphalted oil, and separating the solvent. The dewaxed oil may be subjected to a finishing treatment to improve the colour and carbon residue, and may then be fractionated to give lubricating oils of differing viscosities. Suitable finishing treatments include hydrofinishing, acid treatment and clay filtration, e.g. with fuller's earth, bauxite or "Filtrol" (Registered Trade Mark).
Application Number:
JP1571364A
Publication Date:
September 17, 1974
Filing Date:
March 23, 1964
Export Citation:
International Classes:
C10G53/06; C10G67/04; C10G73/06