New clean ammonia production method could be 60% cheaper than using green hydrogen, says US university

A novel approach to synthesizing ammonia from ethanol with the aid of lithium could potentially obviate the necessity for extensive production of renewable hydrogen, thereby facilitating the decarbonization of fertilizers and chemicals. Researchers in the United States have devised a new method for producing clean ammonia, which they estimate could be up to 60% more cost-effective compared to employing green hydrogen for decarbonizing ammonia production. Presently, ammonia is typically manufactured by combining hydrogen gas with nitrogen sourced from the atmosphere using the energy-intensive Haber-Bosch process.

The predominant focus in mitigating emissions from ammonia, especially for applications in fertilizers and other chemical products, has been on decarbonizing the hydrogen feedstock, primarily derived from fossil gas or coal, through the production of green hydrogen via renewables-powered electrolysis. However, a team of researchers at the University of Illinois Chicago (UIC) has devised a novel process called lithium-mediated ammonia synthesis (LMAS), which operates at lower temperatures. This process involves the amalgamation of nitrogen gas and a hydrogen-donating fluid like ethanol with a charged lithium electrode. The nitrogen atoms adhere to the lithium before bonding with hydrogen to form NH3 molecules, as described by the researchers.

Furthermore, both the lithium catalyst and unused hydrogen ions are regenerated in each cycle, thereby circumventing the excess production of H2 gas, a common challenge encountered in similar electrochemical methods of ammonia production. The cost differentials are significant: while grey ammonia's monthly average prices range from $299 to $475 per tonne, green NH3 produced from renewable hydrogen can cost between $750 and $888 per tonne. The UIC research team, led by Meenesh Singh, asserts that upon scaling up, LMAS could potentially reduce costs to $450 per tonne of NH3, representing a substantial 60% reduction compared to other green ammonia production pathways.

Nevertheless, some skepticism has been voiced regarding the research's optimistic portrayal of future cost reductions and the technology's efficacy. Critics have pointed out potential shortcomings in the peer review process and have questioned the accuracy of the techno-economic claims presented.