Sustainable ammonia synthesis from nitrogen wet with sea water by single-step plasma catalysis

Ammonia synthesis at ambient conditions employing intermittent distributed green sources of energy and feedstocks is globally sought to replace the centralized Haber-Bosch (H-B) process operating at high temperature and pressure. We report herein for the first time an effective and sustainable ammonia synthesis pathway from N2 wet with seawater vapor over spherical SiO2 and M/SiO2 (M: Ag, Cu, and Co) catalysts driven by non-thermal plasma (NTP). Experimental results indicate that the presence of a catalyst is required for ammonia produc-tion from seawater vapor and N2. The Co/SiO2 catalyst delivered the highest ammonia synthesis rate (rNH3) of 3.7 mmol gcat-1 h-1 and energy yield of 3.2 gNH3 .kW 1.h-1 at a relatively low input power of 2 W. The extraction of H atoms from H2O molecules plays an important role in the ammonia synthesis from seawater vapor. This work unfolds a novel platform for the subsequent optimization of sustainable ammonia production from endless re-sources such as seawater and N2 through catalytic non-thermal plasma potentially powered by renewable sources.

Automated summary

Ammonia synthesis from N2 wet with seawater vapor using non-thermal plasma over spherical SiO2 and M/SiO2 catalysts is a promising replacement for the centralized Haber-Bosch process. The presence of a catalyst is essential for ammonia production, with the Co/SiO2 catalyst showing the highest synthesis rate and energy yield at a low input power. The extraction of H atoms from H2O molecules plays a crucial role in ammonia synthesis from seawater vapor. This work provides a novel platform for the optimization of sustainable ammonia production from renewable sources.