关键词: 二氧化钛, 二氧化锆, 吡啶, 吸附

Abstract: Anatase TiO₂ and cubic ZrO₂ were prepared by hydrothermal-corrosion method or sol-gel method, respectively, and characterized by X-ray diffraction, N₂ adsorption-desorption and FT-IR and SEM. Using TiO₂ and ZrO₂ as adsorbents and n-dodecane containing pyridine as simulated diesel fuel, the effects of TiO₂ and ZrO₂ dosage, adsorption time and adsorption temperature on the adsorption and denitrification of simulated diesel fuel were investigated. The results showed that the adsorption of pyridine on TiO₂ and ZrO₂ could reach the adsorption equilibrium in a short time, and the adsorption process conformed to the quasi-primary and secondary kinetic equations. The temperature has no obvious effect on the adsorption of pyridine by TiO₂ and ZrO₂, and the adsorption of pyridine by TiO₂ and ZrO₂ is the coexistence of single-layer adsorption and multi-layer adsorption. The adsorption configurations and adsorption energy of pyridine on the TiO₂(101) and ZrO₂(111) crystal surfaces were studied by simulation method. Pyridine can form N—Ti and N—Zr chemical bonds on the crystal surfaces of TiO₂(101) and ZrO₂(111), and the corresponding adsorption energies of pyridine are -188.59kJ/mol and -157.34 kJ/mol, respectively. The results indicated that pyridine could be stably adsorbed on the TiO₂(101) and ZrO₂(111) crystal surfaces.

Key words: TiO₂, ZrO₂, pyridine, adsorption