1,2-Dichloroethane Deep Oxidation over Bifunctional Ru/Ce(x)Al(y) Catalysts

[Image: see text] Ru/Ce(x)Al(y) catalysts were synthesized with impregnation of RuCl(3) aqueous solution on Ce(x)Al(y) (Al(2)O(3)–CeO(2)) and used in 1,2-dichloroethane (1,2-DCE) oxidation. Characterization by X-ray diffraction, Raman, NH(3)-temperature-programmed desorption (TPD), CO(2)-TPD, X-ray photoelectron spectroscopy, and H(2)-temperature-programmed reduction indicates that CeO(2) exists as a form of face-centered cubic fluorite structure, whereas the chemical states and the structure of Ru species are dependent on the Ce content. The reducibility and acidity of catalysts increase with Ce/Ce + Al ratio. However, the latter is promoted only in a Ce/Ce + Al range of 0–0.25 and then decreases quickly. Ru/Ce(x)Al(y) catalysts have considerable activity for 1,2-DCE combustion. TOF(Ru) of 1,2-DCE oxidation increases with strong acid, which is ascribed to a synergy of reducibility and acidity. Ru greatly inhibits the chlorination through the decreases in both Cl deposition and CH(2)=CHCl formation. High stability of Ru/Ce(10)Al(90) maintains at 280 °C for at least 25 h with CO(2) selectivity of 99% or higher. In situ Fourier transform infrared spectroscopy indicates that 1,2-DCE dissociates to form ClCH(2)–CH(2)O– species, which is an intermediate species for the production of CH(3)CHO and CH(2)=CHCl, the former responsible for deep oxidation.