Ammonia is the fuel for fertilizers and is also a high-energy, CO2-emitting ammonia. Researchers at the University of Illinois Chicago (UIC) with RMIT University Melbourne are advancing project-based innovative cleaner and cost-effective approaches to ammonia production.
Rethinking the Haber-Bosch process for solving ammonia’s carbon problem
Ammonia production presently involves the Haber-Bosch process, which is energy and hydrogen intensive; quite a large part of hydrogen derives from fossil fuels. Such characteristics make the ammonia industry an excellent contributor to global CO2 emissions.
A new method-lithium-mediated ammonia synthesis (LMAS) was devised and developed by the team at the University of Illinois Chicago. The main process involves using the lithium electrode in conducting reactions with nitrogen and hydrogen.
This makes temperature processes unnecessary. What really makes it different compared to others is that LMAS has the potential of drastically reducing production costs. Traditional green ammonia, for instance produced from renewable hydrogen, tends to be expensive, with prices ranging from $750 to $888 for every tonne produced.
The LMAS technology could as much as reduce this price by up to 60%, making it possible to produce ammonia for as little as $450 per tonne. This is as gigantic a boon as one can expect, especially because the key constituent used in the whole thing-the ethanol-is massively produced and relatively cheap.
This however is still very promising technology and has some critiques when it comes to cost reductions because it is debatable whether the technology would prove itself more efficient and economically sound in the long run than claimed.
Liquid metal catalyst of RMIT: Ammonia production reversed
Out here in the rest of the world, researchers at RMIT University in Melbourne are inventing a radically different concept of ammonia production. They built a liquid metal catalyst from copper and gallium for the first time for ammonia synthesis.
The ‘nano planets’ work well at lower pressure and temperature levels compared to the traditional ones since they only require 4 bars pressure and a temperature of 400 degrees C rather than the usual 200 bars and 500 degrees C.
The research shows that the method requires 20% less heat and 98% less pressure than conventional ammonia production (such as this one which is to be produced in America), which would be a great potential for energy savings. The catalyst is so efficient in splitting nitrogen and hydrogen that it allows for production on a very large scale while keeping the carbon footprint much smaller.
The process can play a very important role in the hydrogen economy, enabling ammonia to become a much safer and efficient carrier for hydrogen storage and transport. In the future, this could allow green energy to be sold rather than wasted in conversion losses associated with long-distance energy transportation.
From fertilizers to fuel: Ammonia of the future
Indeed, the ramifications of these two technologies may go beyond ammonia production. Ammonia is intended to serve an important future role as a clean shipping fuel since, it can be converted into hydrogen for use on-demand.
Apart from the liquid metal catalyst of RMIT and LMAS, they offer pathways to a more sustainable future for ammonia-reliant industries through reducing the carbon footprint associated with ammonia production. The real test, however, would be to scale these technologies up to satisfy global demand.
The lifecycle emissions of the lithium-based LMAS technology have yet to be determined, along with issues of efficiency and scalability of both methods. Nonetheless, both teams are actively improving their respective technologies. They are in collaboration with industry partners exploring the pathways of commercialization.
These cutting-edge processes in ammonia production, which rely on lithium-mediated synthesis and liquid metal catalysis, have the potential to revolutionize energy consumption, cost, and CO2 emission. They could, however difficult, contribute greatly to decarbonizing industries and make an important contribution to that most forward-looking and hopeful future (like the one discovered in a 20-million-year-old mine in Finland).