PREMIUM SYNTHETIC LUBRICANT BASE STOCK

摘要

A premium synthetic lubricating oil base stock having a high VI and low pour point is made by hydroisomerizing a Fischer-Tropsch synthesized waxy, paraffinic feed wax and then dewaxing the hydroisomerate t o form a 650-750 .degree.F+ dewaxate. The waxy feed has an initial boiling point in the range of about 650-750 .degree.F, from which it continuously boils up to at least 1050 .degree.F and has a T90-T10 temperatu re difference of at least 350 .degree.F. The feed is preferably hydroisomerized without any pretreatment, other than optional fractionation. The 650-750 .degree.F+ dewaxate is fractionated into two or more base stocks of different viscosity.