A METHOD FOR MAKING LUBE BASESTOCKS

摘要

The present invention relates to a process for preparing lubricating oil basestocks having a high viscosity index from wax containing feeds. The process includes the steps of conducting a lubricating oil feedstock to a solvent extraction zone and underextracting the lubricating oil feedstock to produce at least an aromatic-lean raffinate solution; removing at least a portion of the extraction solvent from the aromatics-lean raffinate solution to produce a raffinate feedstock having a dewaxed oil viscosity index from 75 to 105 and a wax content of greater than 15 wt%; contacting the raffinate feedstock with a hydrotreating catalyst in a first reaction stage to produce a gaseous product and a hydrotreated feedstock; stripping the hydrotreated feedstock to separate the gaseous product; contacting the stripped feedstock with a dewaxing catalyst in a dewaxing zone where the dewaxing catalyst contains at least one Group VIII noble metal and is ZSM-48; and contacting the lubricating oil basestock with a mesoporous hydrofinishing catalyst from the M41S family in a hydrofinishing zone to produce a hydrofinished lubricating oil basestock.