Activity of NiW catalysts supported on TiO2-Al2O3 mixed oxides: Effect of Ti incorporation method on the HDS of 4,6-DMDBT

The method of titanium incorporation was studied in TiO2-Al2O3 mixed oxide supports synthesized by two methods: impregnation of boehmite and impregnation of alumina. The supports were impregnated with Ni and W and evaluated for the hydrodesulfurization (HDS) of 4,6-dimethyldibenzothiophene (DMDBT). All the materials were characterized by nitrogen physisorption, Raman and UV–vis–DR spectroscopies. The results show that the method of impregnating the alumina surface with the titanium oxide precursor, allows obtaining supports with greater degree of surface polymerization of structures Tisingle bondOsingle bondTi and with higher semiconducting character in which a greater proportion of the most basic OHʹs is eliminated. These combined effects produced more active HDS catalysts.