PROCESS TO PREPARE A BASE OIL

摘要

Process to prepare a lubricating base oil having a saturate content of more than 90 wt%, a sulphur content of less than 0.03 wt% and a viscosity index of more than 80 starting from an intermediate lubricating base oil product having a saturates content of below 90 wt% and a sulphur content of above 0.03 wt%, which intermediate lubricating base oil product is obtained by first removing part of the aromatic compounds by means of solvent extraction of a petroleum fraction boiling in the lubricating base oil range resulting in a solvent extracted product and subsequently solvent dewaxing the solvent extracted product to obtain the intermediate lubricating base oil product wherein said intermediate product is contacted with a hydroprocessing catalyst in the presence of hydrogen, wherein said hydroprocessing catalyst comprises one or more metals of Group VIII and one or more metals of Group VIb in their oxide or sulfide form and a refractory oxide and the total content of the metals, calculated as if they are in their oxidic form, is greater than 60 wt%.