Catalytic Behaviour of Ce-Doped Ni Systems Supported on Stabilized Zirconia under Dry Reforming Conditions

oleh: Ahmed Sadeq Al-Fatesh, Yasir Arafat, Ahmed Aidid Ibrahim, Samsudeen Olajide Kasim, Abdulrahman Alharthi, Anis Hamza Fakeeha, Ahmed Elhag Abasaeed, Giuseppe Bonura, Francesco Frusteri

Format: Article
Diterbitkan: MDPI AG 2019-05-01

Deskripsi

Ni supported on bare and modified ZrO<sub>2</sub> samples were synthesized using the incipient wet impregnation method. The <i>t</i>-ZrO<sub>2</sub> phase was stabilized by incorporation of La<sub>2</sub>O<sub>3</sub> into ZrO<sub>2</sub>. Moreover, the influence of CeO<sub>2</sub>-doping on the physico-chemical and catalytic properties under CO<sub>2</sub> reforming conditions was probed. The characterization data of the investigated catalysts were obtained by using XRD, CO<sub>2</sub>/H<sub>2</sub>-TPD, BET, TPR, TPO, TGA, XPS and TEM characterization techniques. In the pristine Ni/Zr catalyst, the <i>t</i>-ZrO<sub>2</sub> phase transformed into the monoclinic phase. However, upon support modification by La<sub>2</sub>O<sub>3</sub>, significant effects on the physicochemical properties were observed due to the monoclinic-to-tetragonal ZrO<sub>2</sub> phase transformation also affecting the catalytic activity. As a result, superior activity on the La<sub>2</sub>O<sub>3</sub> modified Ni/Zr catalyst was achieved, while no relevant change in the surface properties and activity of the catalysts was detected after doping by CeO<sub>2</sub>. The peculiar behavior of the Ni/La-ZrO<sub>2</sub> sample was related to higher dispersion of the active phase, with a more pronounced stabilization of the <i>t</i>-ZrO<sub>2</sub> phase.