Microwave-enhanced catalytic ammonia synthesis under moderate pressure and temperature

In this study, an alternative approach based on microwave-enhanced ammonia synthesis for Haber-Bosch process was carried out under moderate pressure of 0.1–0.65 MPa and temperature range of 280–400 °C over a stable CsRu/CeO2 catalyst. The ammonia production rate is significantly improved under microwave conditions. At 0.65 MPa and 320 °C, maximum ammonia production rate was achieved at H2/N2 ratio of 1/1. Stable performance was obtained in a 6-cycles of startup-shutdown operation for cumulative on-line time of 80 h. The work demonstrates the potential of microwave catalytic technology for the distributed ammonia synthesis using renewable power having intermittent nature of energy supply. [Display omitted] •Microwave-enhanced NH3 synthesis is a promising alternative for H-B process.•High pressure quartz reactor was designed and used in MW NH3 synthesis.•NH3 production rate were enhanced by increasing pressure and lowering H2/N2 ratio.•Effects of process parameters for NH3 production rate are systematic investigated.•MW catalytic is a potential technology for the NH3 synthesis using renewable power.