Preparation and characterization of Ni-Ti-O mixed oxide for selective catalytic reduction of NO under lean-burn conditions

Abstract

A novel Ni-Ti-O mixed-oxide catalyst was prepared by a homogeneous coprecipitation method and tested in the selective catalytic reduction of NO by propene (C 3 H 6 -SCR) in the presence of excess O 2 . Catalysts with different molar ratios of Ni-Ti were characterized using X-ray diffraction, N 2 adsorption-desorption, pyridine adsorption, temperature-programmed desorption, and in-situ Fourier-transform infrared spectroscopy. The Ni 1 Ti 1 catalyst showed good activity in C 3 H 6 -SCR at 430 °C and the NO x conversion achieved 68%. This catalyst displayed an anatase structure and had a high surface area (149 m 2 /g), which is helpful to enhance the catalyst activity. Lewis acid sites were beneficial for adsorbing nitrate, which was the main intermediate produced during the SCR of NO by C 3 H 6 . A novel Ni-Ti-O mixed-oxide catalyst was used in the selective catalytic reduction of NO by C 3 H 6 under lean-burn conditions; the catalyst demonstrated good activity at 430 °C.