Microwave-assisted synthesis of MgO–CNTs supported ruthenium catalysts for ammonia synthesis

Small and uniform ruthenium nanoparticles (1.3–2.0 nm) supported on the mixture of MgO and carbon nanotubes (CNTs) were prepared by microwave irradiation and the promoted Ru/MgO–CNTs (K–Ru/MgO–CNTs-a) exhibited high activity for ammonia synthesis. The results show that the highest activity of the K–Ru/MgO–CNTs-a catalyst is 5631μmolh-1g-cat-1 under 0.20 MPa at 683 K. The activity is 2.2 times as active as that of K–Ru/MgO–CNTs-b prepared by conventional wet impregnation process. Moreover, this method preparing K–Ru/MgO–CNTs-a catalyst is fast and simple.