Patent ID: 6325918
Filing Date: 2001-12-04
Classification: C10G

Abstract:
A lubricating oil basestock produced by a process which comprises:(a) conducting a lubricating oil feedstock, said feedstock being a distillate fraction, to a solvent extraction zone and under-exacting the feedstock to form an under-extracted raffinate;(b) stripping the under-extracted raffinate of solvent to produce an under-extracted raffinate feed having a dewaxed oil viscosity index from about 85 to about 105 and a final boiling point of not greater than about 600.degree. C.;(c) passing the raffinate feed to a first hydroconversion zone and processing the raffinate feed in the presence of a non-acidic catalyst at a temperature of from about 340 to about 420.degree. C., a hydrogen partial pressure of from about 800 to about 2000 psig, space velocity of about 0.2 to about 3.0 LHSV, and a hydrogen to feed ratio of from about 500 to about 5000 Scf/B (89 to 890 m.sup.3 /m.sup.3) to produce a first hydroconverted raffinate; and(d) passing the first hydroconverted raffinate to a second reaction zone and conducting cold hydrofinishing of the first hydroconverted raffinate in the presence of a hydrofinishing catalyst at a temperature of from about 200 to about 320.degree. C., a hydrogen partial pressure of from about 800 to about 2000 psig, a space velocity of from about 1 to about 5 LHSV, and a hydrogen to feed ratio of from about 500 to about 5000 Scf/B (89 to 890 m.sup.3 /m.sup.3) to produce a hydrofinished raffinate.