| 摘要 |
A process to prepare a spindle oil, light machine oil and a medium machine oil base oil grade by: (a) performing a separate catalytic dewaxing on a spindle oil fraction, a light machine oil fraction and a medium machine oil fraction as obtained in a vacuum distillation of a bottoms fraction of a fuels hydrocracking process; (b) performing a separate hydrofinishing of the light and medium machine oil fractions obtained in step (a); (c) separating the low boiling compounds from the spindle oil, light machine oil and medium machine oil fractions as obtained in step (a) and (b) and obtaining the spindle oil, light machine oil and medium machine oil base oil grade; (d) wherein the vacuum distillation is performed by altematingly performing the distillation in two modes wherein the first mode (d 1 ) the bottoms fraction is separated into a gas oil fraction, a spindle oil fraction, a medium machine oil fraction and a first rest fraction boiling between said spindle oil and medium machine oil fraction and in the second mode (d 2 ) the bottoms fraction is separated into a gas oil fraction, a spindle oil fraction, a light machine oil fraction and a second rest fraction boiling above the light machine oil fraction. |
