Énergie
La production d’ammoniac est extrêmement néfaste pour l’environnement – Des ingénieurs viennent de développer une méthode plus propre
Ammonia: Du polluant à l’alternative verte
Ammonia has been discussed as an alternative to fossil fuels for applications hard to electrify, like shipping, trucking, or long-term energy storage. It has also been proposed as an intermediary step for the safe transport of hydrogen that can then be used in fuel cells.
Usually, producing ammonia relies on combining hydrogen with nitrogen gas under high pressure and temperatures, a process called the Haber-Bosch Process. Unfortunately, this method is polluting and not very energy efficient.
Source: Research Gate
À la place, des chercheurs de the University of Illinois, Texas Tech University, et General Ammonia Company ont optimisé une nouvelle méthode de production d’ammoniac qui exploite l’éthanol avec une électrode de lithium chargée.
Ce n’est pas leur première percée, avec des travaux antérieurs sur electrocatalytic screens (un treillis de cuivre) pour la production d’ammoniac, ainsi que sur “solar-to-fuel“ ammonia generators.
Lithium “Symphony” For Green Ammonia Production
The new ammonia production method works by combining nitrogen gas and a hydrogen-donating fluid such as ethanol with a charged lithium electrode.
This “Lithium-mediated ammonia synthesis” (LiMAS) works in 3 successive steps:
- Premièrement, une étape appelée électrodéposition de Li+. Elle est réalisée avec des oscillations de courant afin d’assurer une interface solide-électrolyte (SEI) de haute qualité et une stabilité de tension.
- Deuxièmement, la molécule d’azote adhère au lithium dans un processus appelé nitruration du lithium.
- Troisièmement, la protolyse du Li3N ajoute les atomes d’hydrogène à l’azote, créant de l’ammoniac (NH3).
Source: ACS Publications
The researchers describe the process as a “symphony,” as each step is regulated in such a way that the process stays efficient and keeps the material cycling for the next loop of chemical reactions.
“Il y a deux boucles qui se produisent. L’une est la régénération de la source d’hydrogène et la seconde est la régénération du lithium. Il y a une symphonie dans cette réaction, due au processus cyclique.
Ce que nous avons fait, c’est comprendre cette symphonie de manière plus approfondie et essayer de la moduler de façon très efficace, afin de créer une résonance et de la faire avancer plus rapidement.” – Singh, professeur associé en génie chimique à l’UIC.
The electrodeposition step is the most important innovation done in this research, as it greatly improves NH3 selectivity.
They also found two other factors that boost the productivity of ammonia generation:
- Augmenter la pression du gaz azote jusqu’à 20 bars.
- Utiliser l’alcool comme source d’hydrogène.
- Le 1-butanol, donneur d’hydrogène, a donné le rendement le plus élevé
- L’eau est un donneur d’hydrogène beaucoup moins efficace, contrairement à ce que la communauté scientifique croyait jusqu’à présent.
Dans l’ensemble, ces connaissances rendent la LiMAS à haute pression (« synthèse d’ammoniac médiée par le lithium ») plus productive que la LiMAS à basse pression et que le procédé Haber‑Bosch.
Source: UIC Today
The Problems From Ammonia Production
Green Ammonia
We mentioned how ammonia production is likely a crucial step in decarbonizing the entire sector of the economy and creating a hydrogen economy. We discussed this in our article “Decarbonizing Global Shipping Lanes through Green Ammonia“.
This is especially true if the process is powered by green energy (including using green hydrogen), as other forms of ammonia are less eco-friendly.
This distinguishes green ammonia from other types of ammonia:
- Ammoniac gris/marron: produit à partir de combustibles fossiles.
- Blue ammonia is produced from fossil fuels but with carbon capture.
- Pink ammonia (sometimes also called yellow ammonia): produced from nuclear energy.
- Turquoise ammonia: produit à partir de la pyrolyse du méthane. Cela décompose le méthane en hydrogène et carbone solide, ce dernier pouvant ensuite être stocké ou utilisé pour des applications comme les fibres de carbone.
Aujourd’hui, la plupart de l’ammoniac est produit pour des applications telles que la production d’engrais et l’industrie chimique (colorants, explosifs, etc.). Il est principalement fabriqué en utilisant des combustibles fossiles, notamment le gaz naturel.
En conséquence, l’ammoniac se classe deuxième après le ciment parmi les processus industriels en termes d’émissions de carbone, représentant 1,5 % des émissions totales de carbone.
Les hautes températures requises par le procédé Haber‑Bosch n’aident pas non plus à réduire la facture énergétique de la production d’ammoniac, l’énergie étant souvent issue de combustibles fossiles, y compris le charbon à fortes émissions de carbone.
Industrializing LiMAs
While lithium is not the cheapest material, it is not extraordinarily expensive either and does not get consumed by the ammonia generation using high-pressure LiMAS.
So, combined with the high energy efficiency, this method is a low-cost source of ammonia.
The University of Illinois researchers estimate that if scaled up it would be economically viable
“le processus produirait de l’ammoniac à $456 par tonne, ce qui représente 60 % moins cher que les approches antérieures basées sur le lithium et d’autres méthodes vertes proposées”.
Singh, professeur associé en génie chimique à l’UIC.
This would make that method of production in the same range as other green alternatives still in development, like for example Fuel Positive’s containerized ammonia generation system, aiming for CA$560/ton, or AmmPower’s modular ammonia system with $360/ton for electricity cost alone (not counting maintenance and capital expenditures).
(We discuss these 2 companies and others in our article “The Other Hydrogen Fuel – Top 5 Green Ammonia Stocks”)
$456 per ton would also be in line with most of the world’s regional prices for ammonia, currently driven by fossil fuel-based production.
Ammonia prices are also exposed to wild fluctuation when natural gas prices go up, like in 2022 at the beginning of the war in Ukraine.
Source: BusinessAnalitIQ
The scientists are already partnering with General Ammonia Co. to pilot and scale up their lithium-mediated ammonia synthesis process. A pilot plant will be built in the Chicago area and the University of Illinois Office of Technology Management has filed a patent for the process.
Green Ammonia Companies
1. General Ammonia Company
The company partnering with the University of Illinois’ researchers is not publicly listed, but is “actively seeking investment”.
Accredited investors might be interested in directly contacting them and discussing the possible terms of investment in the company and its high-pressure LiMAS pilot plant.
2. NitroVolt
NitroVolt is another company looking to create ammonia using LiMAS, with a patent pending for the lithium-mediated ammonia synthesis process.
Source: NitroVolt
The Danish company is combining the LiMAS process with its proprietary flow cell system, allowing for a continuous, high-efficiency reaction.
The company’s research has been published in prestigious scientific publications, notably:
- Science:
- Nature: A rigorous electrochemical ammonia synthesis protocol with quantitative isotope measurements
Source: NitroVolt
L’entreprise a reçu son premier investissement le 6er, 2024 de VC firm BackingMinds.
3. FuelPositive Corporation (NHHHF)
FuelPositive has created a modular/containerized green ammonia generation system. Its first target is the agricultural sector, allowing for on-site ammonia production with locally produced energy. The system can generate up to 300kg/day, 100 tons per year of ammonia for CA$950,000.
Source: Fuel Positive
This makes it a system fit for farms up to 1,800 acres. With just 1.5 acres of land covered with solar panels, enough to power the ammonia generation.
Source: Fuel Positive
FuelPositive claims its system can produce ammonia for CA$560/ton,
The start-up is at an early stage, with full-scale production scheduled for 2025, and 30 orders confirmed so far, with the first delivery scheduled for mars 2024.
The main strength of FuelPositive is the modularity of its technology, allowing for a more distributed approach and standardized mass production of its ammonia generation module.
The company is building a partnership with Cipher Neutron, which can produce hydrogen without any metal of the platinum group.
A similar partnership to use/license the LiMAS method for ammonia production could be established, as the company’s strength is in its modular design, more than a proprietary ammonia generation technology.
While the primary focus is fertilizer production, the ammonia could be used to power farming engines with energy produced on-site, depending on the speed of adoption of ammonia/hydrogen-powered farming tools.
The decentralized and modular nature of FuelPositive systems could also make them a key element of a future ammonia economy. The fertilizer market can provide the gap for the company to grow until the use of hydrogen and ammonia is more widespread.
4. AmmPower Corp. (AMMPF)
AmmPower is similar to FuelPositive in that it provides modular ammonia generation systems, but at a larger scale, with its base module able to produce 4 tons/day. This puts the company more into the field of very large farms (10,000+ acres) or industrial operations like textiles, refrigeration, mining, pharmaceuticals, or semiconductors.
Source: AmmPower
The company is in the process of building its order book, with the near-term booking potential estimated at $30M, and sale prospects for 690 units from 52 countries.
The company estimates the electricity cost to be around $360/ton of ammonia.
The modularity of the system allows for a quick turnaround and deliveries, with less than a year compared to the 3-4 years of similar projects without the modular approach.
It is also working on technology to transform waste into ammonia, in a joint venture with CTEC Energy Sales USA.
Here too, other partnerships could be established to integrate the LiMAS ammonia process into the modular design.
To further the progress of ammonia into a hydrogen-ammonia economy, it creates a dedicated subsidiary dedicated to cracking ammonia into hydrogen, which will look for additional funding separately.
By striking the scale that might fit most industrial usage, as well as very large farms, AmmPower is aiming for clients and companies with deeper access to capital than most.
Combined with ammonia cracking technology, this could allow it to scale up quickly following policies to push for the development of hydrogen as an energy carrier.
