The effects of MCM-41's calcination temperature on the structure and hydrodenitrogenation over NiW catalysts

MCM-41 was calcined at 500, 560, 600 or 650 degrees C. It was used as support for NiW catalysts of hydrodenitrogenation (HDN) for quinoline in order to investigate the influences of the MCM-41's calcination temperature on the structure and the HDN performance of NiW catalysts. The NiW catalysts were characterized by XRD, N-2 adsorption-desorption, XPS, Raman, HRTEM and Py-IR techniques. The results showed that the surface area (S-BET), the average pore diameter (Dp) and the pore volume (Vp) of the MCM-41 increased with increase of the MCM-41's calcination temperature. The high S-BET, Dp and Vp were beneficial for the high dispersion of W species, the formation of appropriate nature of W species and acid sites on the catalysts. The HDN activity followed the order of NiW-650 approximate to NiW-600>NiW-560>NiW-500, while the relative selectivity of HDN pathways was similar for all the catalysts.