Low-Temperature Catalytic Dry Reforming of Methane over Pd Promoted Ni–CaO–Ca<sub>12</sub>Al<sub>14</sub>O<sub>33</sub> Multifunctional Catalyst
Chengxiong Dang, Jinlu Luo, Wenwen Yang, Hanke Li, Weiquan Cai
Abstract
The dry reforming of methane (DRM) suffers from high energy consumption and catalyst deactivation over time on stream at high operating temperatures (>800 °C). Here, we demonstrate that DRM is effectively catalyzed at 600 °C by Pd promoted Ni–CaO–Ca12Al14O33 multifunctional adsorbent/catalyst materials with 67% CO2 conversion, 68% CH4 conversion, and a H2/CO ratio close to unity. Notably, the catalyst shows no sign of deactivation at 600 °C for a 50 h continuous on-stream DRM reaction. The high performance is ascribed to the enhanced CH4 dissociation activity with the presence of Pd. CH4 reformed with CaCO3 achieved the transformation between bulk CaCO3 and nanoparticles of CaO. The dynamic transformation may allow for reversible encapsulation and release of Ni particles, thereby suppressing Ni sintering. Furthermore, the coke formed on the catalyst is mainly the active carbon species which is easily removed by CO2 and CaCO3, thus ensuring the long-term stability. The results demonstrated herein shed light on a new paradigm to design low-temperature DRM reaction catalysts.