Promotion of hydrogenation activity and sulfur resistance over Ni/ASA catalyst by support modification simultaneously with P and USY

Abstract

Individual and simultaneous P and USY promoted amorphous SiO₂–Al₂O₃ (ASA) supported Ni catalysts were prepared using the hydrothermal synthesis method with the assistance of cis-9-octadecenylamine. The catalysts were characterized by X-ray diffraction (XRD), N₂-adsorption and desorption, UV-vis diffuse reflectance spectroscopy, FTIR spectroscopy of adsorbed pyridine (Py-IR), transmission electron microscopy (TEM), temperature-programmed hydrogen reduction (H₂-TPR) and X-ray photoelectron spectroscopy (XPS). The effects of P and USY loading on the activity of naphthalene hydrogenation were evaluated in a fixed bed reactor under the following reaction conditions: P = 4 MPa, GHSV = 16 h⁻¹, H₂/oil = 600 volume ratio, T = 200, 240, 280 and 320 °C. Experimental results verified that all individual P and USY modified catalysts displayed higher hydrogenation activity than the freely P and USY decorated catalyst at 200–280 °C. Furthermore, the catalyst simultaneously modified with 1.0 wt% P and 10 wt% USY had the highest hydrogenation activity and sulfur tolerance. Multiple effects, such as metal dispersion, acid amount, surface exposure of the active Ni° species and the [Ni_Oh²⁺]/[Ni_Td²⁺] ratio were responsible for the high hydrogenation activity of P and USY-promoted catalysts.