SATURATION PROCESS FOR MAKING LUBRICANT BASE OILS

摘要

Systems and methods are provided for hydroprocessing a petroleum fraction, such as a bottoms fraction from a fuels hydrocracking process, to generate a lubricant base oil. The aromatic content of such a petroleum fraction can be reduced using a aromatic saturation stage with multiple catalyst beds, or alternatively using a reactor (or reactors) with multiple aromatic saturation stages. The catalysts in the various beds or stages can be selected to provide different types of aromatic saturation activity. An initial bed or stage can provide activity for saturation of 1-ring aromatics in the petroleum fraction. One or more subsequent beds or stages, operating at successively lower temperature, can then be used to reduce the multiple-ring aromatic content of the petroleum fraction.

主权项

1. A method for producing a lubricant base oil, comprising:
contacting an input feed having an aromatics content of at least 600 mmol/kg with a first catalyst under first effective aromatic saturation conditions to produce a first effluent containing less than 600 mmol/kg of aromatics, the first effective aromatic saturation conditions including a temperature of at least 300° C.; contacting the first effluent with a second catalyst under second effective aromatic saturation conditions to produce a second effluent, the second effective aromatic saturation conditions including a temperature of from 270° C. to 300° C. and a hydrogen partial pressure of at least 4.1 MPag (600 psig); and contacting the second effluent with a third catalyst under third effective aromatic saturation conditions, the third effective aromatic saturation conditions including a temperature of from 220° C. to 260° C.