摘要 |
<p>The invention concerns an improved method for making very high quality oil bases optionally with simultaneous production of high quality middle distillates, comprising hydrotreating, hydrocracking preferably on Y or beta zeolite, topping steps. The effluent is subjected to catalytic dewaxing on ZSM-48 zeolite. The method then comprises steps of hydrofinishing to hydrogenate the aromatics, preferably on a catalyst comprising at least a noble metal of group VIII, chlorine and fluorine and steps of vacuum topping. The properties of the oils and middle distillates are enhanced (flow point, viscosity index, aromatic content) resulting even in production of medicinal oils.</p> |