CO methanation over ZrO2/Al2O3 supported Ni catalysts: A comprehensive study

A series of ZrO2/Al2O3 composite oxides with different ZrO2 contents were prepared by impregnation method. The NiO/ZrO2/Al2O3 catalysts for CO methanation were prepared and tested in a tubular microreactor under the condition of T = 300–650 °C, P = 1.5 MPa, GHSV (gas hourly space velocity) = 10,000 h− 1, and H2/CO = 3. The results revealed that adding ZrO2 restrains the formation of NiAl2O4, weakens the Ni–Al2O3 interaction, and makes the catalyst more easily reduced, enhancing significantly the activity of catalyst. Especially, among these catalysts, 20Ni/40ZA catalyst with ZrO2 content of 40 wt.% exhibits high CO conversion and CH4 selectivity in a broad temperature region of 300–550 °C. Moreover, 20Ni/40ZA performs superior stability than 20Ni/Al2O3. The added ZrO2 also improves the anti-carbon deposition and anti-sintering performance of Ni/Al2O3 catalyst.