Process for dewaxing of petroleum oils prior to demetalation and

Abstract

The catalytic demetalation and desulfurization of a residual oil is substantially improved by subjecting the residual oil to hydrodewaxing prior to the demetalation and desulfurization comprising prior to contacting the residual oil with demetalation and desulfurization catalysts, contacting the residual oil, under hydrodewaxing operating conditions effective to significantly reduce the pour point of the residual oil and to cause substantially little demetalization of the residual oil, with a catalyst comprising about 1 to about 10 weight percent of a Group VIB metal, the metals based on the total catalyst, and being present as the oxides or sulfides on a support comprising a composite of alumina and about 5 to about 25 weight percent of a ZSM-5 crystalline zeolite based on the total composite, the catalyst having at least 60 percent of its pore volume in the 50 to 200 Angstroms diameter range or at least 50% of the pore volume in the 30 to 100 Angstroms diameter range.