Approach Developed to Synthesize Ammonia in Ambient Conditions

To meet global food demands, environmentally friendly and energy-efficient ways to produce ammonia for fertilizer production are essential.

Currently, ammonia is obtained almost exclusively through the Haber-Bosch process, which operates at high temperatures and requires specialized facilities and centralized plants. This has inhibited ammonia production in developing regions, restricting access to fertilizers and limiting agricultural output.

However, a team led by researchers in Georgia Tech’s School of Chemical and Biomolecular Engineering has demonstrated a new approach to mechanocatalytically synthesize ammonia under nominally ambient conditions that could enable localized, on-demand production in developing parts of the world.

The researchers, who recently published their study in ACS Energy Letters, applied mechanical energy to drive the reaction in ball mills.

Milling titanium powder in a vibratory ball mill with a stainlesssteel milling vessel modified to allow a steady gas flow of nitrogen and hydrogen resulted in the formation of titanium nitride (TiN) and the continuous synthesis of ammonia without the need for external heating or pressuring.

“You don’t have to heat a reactor because the balls create localized hot spots,” explained ChBE Professor Carsten Sievers. “Because of the localized energy input, reactions that traditionally require elevated temperatures and pressures can occur in reactors at nominally ambient conditions.”