PETROLEUM FEEDSTOCK SEPARATION PROCESS Russian patent published in 2004 - IPC

FIELD: petroleum processing and petrochemistry.

SUBSTANCE: in production of regular and high-index lubrication oils, oil fractions are mixed with selective solvent containing complexing additive and resulting mixture is cooled to form suspension, from which high-melting hydrocarbons are separated. Complexing additive is selected from aqueous urea or thiourea solution, or their mixture in amount 0.01 to 6 vol %, which is separated on heating from products in solvent regeneration stage after solid phase separation stage and returned into the process. Solvent is selected from methyl t-butyl ether and its mixture with one of the following components: C₃-C₆-ketones, C₁-C₅-alcohols, C₂-C₁₂-ethers, halogenated hydrocarbons, N-methylpyrrolidone, or with their mixture. Advantageously, mixture of methyl t-butyl ether (85-99.8 vol %) with acetone is used.

EFFECT: increased separation efficiency and raised melting point of gatch (petrolatum).

5 cl, 6 tbl