ElectrIfied ammoNia CrAcking iN sTructured reactors

Informazioni relative al progetto

INCANT

ID dell’accordo di sovvenzione: 101123385

DOI

10.3030/101123385

Progetto chiuso

Data della firma CE 4 Luglio 2023

Data di avvio 1 Ottobre 2023

Data di completamento 31 Marzo 2025

Finanziato da

• European Research Council (ERC)

Costo totale

Nessun dato

Contributo UE

€ 150 000,00

Coordinato da

POLITECNICO DI MILANO
Italy

Periodic Reporting for period 1 - INCANT (ElectrIfied ammoNia CrAcking iN sTructured reactors)

Periodo di rendicontazione: 2023-10-01 al 2025-03-31

Sintesi del contesto e degli obiettivi generali del progetto

The energy transition requires effective hydrogen transportation and storage solutions. While ammonia is considered an ideal hydrogen carrier, the absence of efficient industrial technologies for its decomposition (cracking) remains a major challenge for hydrogen recovery. The INCANT project aims to develop and validate breakthrough technology to convert ammonia into hydrogen. Building on previous ERC projects, it features an electrified catalytic reactor that utilizes direct ohmic heating of porous cellular structures, such as open-cell foams or 3D-printed materials (POCS), packed with catalyst particles. The high porosity structures can host a large catalyst inventory, enhancing the efficiency of the ammonia cracking process, while the reactor’s design ensures uniform heat generation across the catalyst bed via the Joule effect to sustain the endothermic cracking reaction, enabling in principle thermal efficiencies close to 100 %. The goal of INCANT is to demonstrate a lab-scale prototype of the novel reactor concept and to assess its potential in view of industrial scale up.

Lavoro eseguito dall’inizio del progetto fino alla fine del periodo coperto dalla relazione e principali risultati finora ottenuti

• A commercial 2% w/w Ru/Al2O₃ catalyst was selected and procured due to its efficiency at low temperatures and safety benefits over Ni or Co-based catalysts.
• A robust and safe test rig suitable for pure ammonia feed was built with automated ammonia leakage detection system.
• Lab-scale kinetic tests were performed (350–550 °C) using Al periodic open cellular internals to ensure isothermal reactor conditions, validating performance in both low and high NH₃ conversion regimes.
• Kinetic dependencies on reactant and product concentrations were assessed by cofeeding N2 and H2 with NH₃. Both a power law and a LHHW rate model provided excellent data fit (mean error =4.3%).
• Three Si-infiltrated SiC open-cell foams were evaluated for electrical conductivity and mechanical strength. High-infiltration samples were selected for their electrical resistance with semiconductor-like behavior at elevated temperatures (Figure 1). POCS geometries had minimal impact on performance at constant porosity.
• A 2D steady-state reactor model from the parent ERC AdG project INTENT was adapted for eNH₃ cracking. The Si-SiC foam was modeled as a resistive heat source, with heat transfer to a homogeneous gas-catalyst pseudo-phase. Kinetics from the previous Task were included to simulate the reactor behavior accurately.
• A lab-scale prototype reactor was assembled with a SiSiC foam packed with 56g of catalyst and inserted in an alumina tube within a steel reactor body.
• Operated with pure ammonia at GHSV between 1250–10,000 Ncc/h/g_cat, the reactor sustained electrical powers up to 485 W (6.1 MW/m³) and temperatures up to 525 °C (Figure 1).
• Peak NH₃ conversion was ~96%, limited by slight flow bypass between ceramic tube and reactor wall—an issue easily addressable by gas-tight sealing in a scaled-up reactor. Thermal efficiency >60% was achieved.
• The reactor showed excellent stability, exceeding 50 hours of operation without degradation.
• Experimental results were used to successfully validate the 2D reactor model across all test conditions (Figure 2).
• The model was used to identify optimal conditions for conversion and productivity. For ≥98% NH3 conversion, a GHSV≤2500 Ncc/h/g_cat with 2.6 MW/m³ power input is required. Maximum H2 productivity (>1.1 kg/h/kg_cat) occurs at GHSV 10,000 Ncc/h/g_cat with 6.3 MW/m³.
• A broader model-based analysis explored trade-offs between conversion, reactor size, temperature and productivity for different applications. Key insights: i) High NH₃ conversions require low GHSV, while H2 productivity peaks at higher GHSV; ii) thus, achieving PEM-grade H2 purity directly from the reactor is not optimal due to the need for low GHSV; optimizing the reactor alongside selective NH₃ removal processes seems more effective for balancing energy use and productivity. iii) Partial NH₃ cracking (20–30% conversion) for ammonia combustion is feasible at high GHSV and high productivity, demonstrating the INCANT reactor flexibility for different end-use cases.

Progressi oltre lo stato dell’arte e potenziale impatto previsto (incluso l’impatto socioeconomico e le implicazioni sociali più ampie del progetto fino ad ora)

Key breakthroughs:
1. Complete kinetic characterization of a Ru/Al2O₃ commercial catalyst under pure NH₃ feed, including co-feeding of H2 and N2, at relevant operating temperatures (350–550 °C): this goes beyond earlier studies that used diluted feeds.
2. Electrification of the ammonia cracking process using Si-SiC open-cell foams as both packed reactor internals and resistive heating elements. Unlike conventional external heating, internal Joule heating of structured reactors allows fast and uniform temperature control. We have demonstrated high thermal efficiencies (>60%) even at lab scale—well above typical values for small-scale cracking systems.
3. A prototype electrified reactor was successfully operated up to 96% NH₃ conversion, powered at 6.1 MW/m³, with T<525 °C. TRL 4 achieved demonstrating 50+ hours of stable operation with a commercial catalyst.
4. An advanced 2D reactor model accurately simulates reactor behavior using kinetics validated across a wide GHSV range. The model enables application-specific tuning of the reactor design (e.g. PEM fuel cells vs. ammonia burners), guiding optimization according to the application needs:
o High-purity H2 production → low GHSV, high conversion
o Combustion-grade NH₃ cracking → partial conversion, high productivity
INCANT results highlight that full NH3 conversion isn't always optimal and suggest hybrid systems integrating selective ammonia separation and recycle, which moves the field towards system-level co-optimization, rather than isolated reactor performance—a key step for industrial deployment.

As part of the INCANT project, we identified the most promising use case for our technology: an onboard, integrated reactor system enabling internal combustion engines (ICEs) to operate on a carbon-free NH₃–H2 mixture. This solution leverages the rapid transient behavior of the system and avoids the need for hydrogen purification. Standard ICEs maintain comparable performance to conventional fossil-fuel engines, confirming the disruptive potential of this configuration in decarbonizing heavy-duty transport applications.
We estimated the EU serviceable market for sub-1000 kW ICEs between €5.3 and €11.5 billion, defining a go-to-market strategy targeting engine manufacturers and vehicle assemblers. Heavy-duty road transport will be our entry point, with maritime propulsion as a follow-up sector. A stepwise development and demonstration roadmap was established to guide future R&D and commercialization.
We also examined relevant regulatory and standardization frameworks, including ATEX, Seveso, IEC, PED, and ISO certifications, and began engaging a multi-sector stakeholder network spanning hydrogen, ammonia, catalysts, ICEs, and mobility. Our preliminary testing confirmed competitive performance-to-cost ratios.
On the IP front, a Freedom-to-Operate (FtO) analysis identified four nearby patents to monitor during our patent drafting process. Business validation through a refined Business Model Canvas clarified our value proposition, customer segments, partnerships, and cost structure—laying the foundation for further research, pilot-scale demonstration, and international market entry.

Joule heated SiSiC POCS under N2 flow in quartz reactor.

Experimental (symbols) and simulated (lines) NH3 conversions (left) and outlet temperatures (right).