MxOy (M = Mg, Zr, La, Ce) modified Ni/CaO dual functional materials for combined CO2 capture and hydrogenation

The integrated CO2 capture and utilization has recently attracted attention as a promising approach to reduce CO2 emissions as well as produce value-added chemicals and fuels. Herein, metal oxides (MxOy, M = Mg, Zr, La, and Ce) modified Ni/CaO dual functional materials (M-Ni/Ca DFMs) were synthesized and applied to the combined CO2 capture and hydrogenation using a single reactor at one temperature. The La–Ni/Ca showed the highest CO2 adsorption capacity (13.8 mmol/g), CO2 conversion (64.3%) and CO yield (8.7 mmol/g). Results indicated that the addition of metal oxides increased the number of basic sites which played important role in efficient CO2 capture. The high activities of M-Ni/Ca were attributed to the formation of highly dispersed small-sized Ni particles. Furthermore, the La–Ni/Ca exhibited excellent cyclic stability after 20 cycles due to the La2O3 as a physical barrier and a support for inhibiting the growth and sintering of CaO and Ni particles.