Highly active MoS2 on wide-pore ZrO2–TiO2 mixed oxides

Wide-pore ZrO2–TiO2 (Zr/Ti = 30/70) was prepared by low-temperature (273 K) sol–gel technique followed by solvo-treatment. Higher surface area (Sg ∼ 340 m2 g−1) and porosity (Vp ∼ 0.8 cm3 g−1) were registered after solvo-treatment at 353 K (1 day) for samples calcined at 773 K. Wider pores (∼22 nm) but much lower Sg (∼80 m2 g−1) were observed when solvo-treatment was carried out at 513 K. Even larger pores with almost no additional Sg decrease were obtained by prolonging that stage. MoS2 catalysts supported on binary oxides solvo-treated at 353 K showed increased intrinsic activity (by a factor of ∼3.3) in dibenzothiophene hydrodesulfurization (593 K and 5.6 MPa), as to that impregnated on conventional ZrO2–TiO2 (at 2.8 Mo atoms nm−2). By itself, Mo sulfidability (as determined by XPS) seemed not to dictate the activity trends found. Surface Lewis acidity appeared to play a decisive role on HDS performance, probably by influencing both Mo sulfidability and dispersion. Highly-loaded catalysts (5.6 Mo atoms nm−2) had decreased activity, probably due to lower MoS2 dispersion. Additional characterization comprised chemical analysis (ICP), XRD, thermal analysis, acidity measurements (by pyridine FTIR) and UV–vis DRS. Tailoring ZrO2–TiO2 texture, traditionally characterized by narrow micro-mesoporosity results promising in developing novel hydrotreating catalyst supports.