Ni-W catalysts supported on commercial gamma-alumina and silica displayed similar activity in dibenzothiophene hydrodesulfurization (DBT HDS), while the activity of the Ni-W/SiO2 catalyst in toluene hydrogenation (HYD) was 6 times higher compared with Ni-W/Al2O3. The dearomatization performance of Ni-W/SiO2 catalyst was tested over a wide range of operation conditions with naphtha and middle distillates. 90% saturation of aromatics in FCC naphtha (340 degreesC, LHSV of 1 h(-1)) and 50% in Light cyclic oil (LCO) (360 degreesC, LHSV of 1 h(-1)) was achieved at 5.4 MPa. In a two stage process with the same Ni-W/SiO2 and intermediate separation of hydrogen sulphide 90% saturation of aromatics in LCO was achieved at 320 degreesC and total LHSV of 0.5 h(-1). At equal conditions, Ni-W/Al2O3 catalyst yielded 1.5-4 times lower total aromatics saturation. (C) 2002 Elsevier Science Ltd. All rights reserved.