GB1281138A - Process for reducing the saturate content of an oil - Google Patents

Abstract

1281138 Solvent extraction TEXACO DEVELOPMENT CORP 8 Feb 1971 4119/71 Heading C5E The primary extract from the solvent extraction of a lubricating oil stock is contacted with a hydrocarbon material comprising a major amount by volume of aromatic hydrocarbons, 1-30% of saturates and 0-20% of aromatic selective solvent to form a secondary extract phase, from which an aromatic oil of reduced saturate content and suitable as a rubber processing oil is recovered, and a secondary raffinate phase. Distillate or residual lube oil stocks are extracted at 160-250‹ F. and the primary extract phases obtained are treated by (a) cooling to 85-160‹ F. to achieve the contacting by forming secondary extract and raffinate phases, (b) adding hydrocarbon material, e.g. stripped primary or secondary extract, to form secondary raffinate and extract phases, or (c) cooling to form secondary extract and raffinate phases followed by adding hydrocarbon material to the secondary extract phase to form third raffinate and extract phases. A surface-active agent such as a long-chain ester of a perfluoroalkyl alcohol, acid, amide or amine can be added to the primary extraction which can be carried out using furfural; other solvents, anti-solvents and diluents are listed.