Industrial gases company Air Liquide says the start of operation of the world’s first pilot of an industrial-scale ammonia cracking process marks a ‘missing technological brick’ in enabling global, low-carbon hydrogen supply chains. The 30 t/d ammonia-to-hydrogen conversion unit is located at the Port of Antwerp, Belgium.

Hydrogen is expected to play a key role in industrial decarbonisation and clean mobility, but transporting the light, volatile molecule over long distances remains a persistent challenge. However, ammonia (NH₃), produced from hydrogen and nitrogen, can be manufactured cost-effectively in regions with abundant solar, wind, hydro or other low-carbon power, transported using existing global infrastructure, and converted back into hydrogen near demand centres. Around 25mn tonnes of ammonia are already moved each year by ship, rail, road and pipeline, creating a ready-made logistics network for future hydrogen imports, according to Armelle Levieux, Group Vice President Innovation & Technology, Air Liquide.

For its Antwerp pilot plant, the company has developed a proprietary cracking process that passes ammonia through catalyst-filled reactor tubes at very high temperatures, above 500°C, to separate hydrogen and nitrogen. The system includes heat-recovery technology. (Watch the video below for an explanation of how the process works.)

The pilot facility depended on R&D in advanced catalysis, ammonia combustion, materials testing, process safety and high-performance gas separation. According to Levieux, the achievement represents far more than a technical milestone. ‘This technological brick is a game-changer for decarbonisation. It means we can envision a future where ammonia is produced in regions with abundant natural resources, like solar and wind, and then transported to industrial hubs around the world to be converted into renewable hydrogen.’  

Under the EU’s Renewable Energy Directive (RED III), at least 42% of hydrogen used in European industry and 29% of energy consumed in transport must come from renewable sources by 2030. Ammonia cracking, Levieux says, offers a ‘concrete path[way]’ for industry to meet these targets.

The Antwerp pilot will also inform future scale-up. Lessons learned will feed directly into Air Liquide’s ENHANCE project, announced in 2023 and awarded €110mn by the European Innovation Fund in late 2024. ENHANCE will see construction of a large-scale renewable ammonia cracker and an innovative hydrogen liquefier within the same industrial zone.

Globally, Air Liquide sees strong momentum for ammonia-based hydrogen supply chains. Western Europe, South Korea and Japan are already signalling significant demand for ammonia imports to decarbonise heavy industry and mobility, notes Levieux. By 2050, the market for renewable and low-carbon ammonia could reach 200mn t/y, she says.