COx-free Hydrogen Production in Additively Manufactured Electrified Reactor through Catalytic Decomposition of Ammonia

Project Information

CHyAMera

Grant agreement ID: 101108281

DOI

10.3030/101108281

Project closed

EC signature date 2 August 2023

Start date 1 February 2024

End date 31 January 2026

Funded under

• Marie Skłodowska-Curie Actions (MSCA)

Total cost

No data

EU contribution

€ 155 559,36

Coordinated by

INSTITUT JOZEF STEFAN
Slovenia

Periodic Reporting for period 1 - CHyAMera (COx-free Hydrogen Production in Additively Manufactured Electrified Reactor through Catalytic Decomposition of Ammonia)

Reporting period: 2024-02-01 to 2026-01-31

Summary of the context and overall objectives of the project

Europe’s transition to a decarbonised energy system, as outlined in the EU Green Deal, will transform how the EU generates, distributes, stores, and consumes energy. Hydrogen will become an important energy vector, as well as a chemical reactant for the decarbonisation of energy-intensive industries like steel. However, as hydrogen is a light, flammable gas, it is difficult to store and transport, and there is always an inherent safety risk. In contrast, ammonia (NH3) is a clean, carbon-free hydrogen carrier with good volumetric and gravimetric energy densities and zero flammability. Green ammonia (produced using renewable energy) could be used as a hydrogen source and then make it available on demand for fuel cells in many applications, so solving the problem of hydrogen storage and transportation. While the catalytic materials for ammonia decomposition are well known (e.g. Ru, Ni), a catalytic reactor/converter with the necessary capabilities must be developed before we can exploit ammonia decomposition as part of a green-hydrogen energy system. For thermodynamic reasons, ammonia can only be decomposed at temperatures of 450 °C. Furthermore, a conventional, passive catalytic reactor requires either the whole reactor – consisting of an inert support material (ceramic tubes or ceramic powder bed) and an active catalyst (e.g. Ru, Ni) – to be heated by convection and/or radiation or for the reaction mixture to be preheated in a heat exchanger before entering the reactor. In both cases a lot of energy is wasted by heating the reactants and the reactor walls. In addition, the time required to reach the reaction temperature hampers the on-demand production of hydrogen.

In this project bottom-up design was applied to fabricate a modular multiscale ceramic catalytic reactor based on embedded magnetic nanoparticles that can provide carbon-free hydrogen on demand by rapidly decomposing ammonia. This approach will reduce energy consumption and improve the reaction kinetics, as well as making possible the decentralised availability of green hydrogen at a reasonable cost.
While the final goal of the project was to demonstrate the viability and advantages of the proposed approach, its main research focus has been on the AM of ceramic catalytic reactor components with magnetic functionality induced by the in-situ formation of magnetic nanoparticles.

The objective was to design and additively manufacture a Si(O)C catalytic support with a porous structure and magnetic functionality induced by (in-situ formed) magnetic nanoparticles exhibiting magnetic heating capability.

The main objective of the proposal was divided into three manageable sub-objectives:
Objective 1: Synthesis of a metal-functionalised, pre-ceramic polymer, yielding a ceramic soft-magnetic nanoparticle (such as Fe3O4/Fe) composite after pyrolysis (WP1)
Objective 2: Design, AM and catalytically functionalise a complex-shaped ceramic catalytic reactor (WP2)
Objective 3: Validate a magnetically heated reactor for carbon-free hydrogen delivery based on the on-demand decomposition of ammonia. (WP3)

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The main objective was achieved by completion of 3 subobjectives, which were further presented through manageable work packages (WP) with clearly defined deliverables and milestones, as laid out in Section 1.2.

Objective 1: Synthesis of a metal-functionalised, pre-ceramic polymer, yielding a ceramic soft-magnetic nanoparticle composite after pyrolysis.

The main achievements:
Modification with Fe-based organometallic precursors
• In situ formation of magnetic nanoparticles (α-Fe, Fe3C, FexSiy) after pyrolyzing Fe-modified polysiloxane (commercially available preceramic polymer was used) under argon.
• Two Fe-based organometallic precursors were investigated (ferric acetylacetonate and ferrocene) by pyrolyzing at various temperatures ranging from 600 °C up to 1500 °C.
• The optimal temperature of 900 °C has been determined based on heating performance under alternating magnetic field.
Modification with Co-, Ni-based organometallic precursors
• In situ formation of magnetic nanoparticles (Co, Ni) after pyrolyzing Co/Ni-modified polysiloxane.
• The optimal temperature of 700 °C has been recorded based on heating performance.
• The phase composition development was studied to understand phase formation and nanoparticles’ size effects onto heating performance.

Objective 2: Design, AM and catalytically functionalise a complex-shaped ceramic catalytic reactor.

The main achievements:
• Various Triply Periodic Minimal Surfaces (TPMS) structures, featuring high strength-to-weight ratios, high surface-area-to-volume ratios, and enhanced thermal/mass transport compared to traditional support structures were used to design cylindrical reactor monolith.
• The photosensitive formulation suitable for vat photopolymerization additive manufacturing technique was developed to enable printing of metal modified polysiloxanes.
• The optimal printing parameters were determined.
• The cylindrical reactor monoliths were successfully printed and pyrolyzed at optimal temperatures considering achieved heating under alternating magnetic field.
• Dip coating method was used to coat Ru nanoparticles on the surface and microchannels of pyrolyzed reactor monolith.

Objective 3: Validate a magnetically heated reactor for carbon-free hydrogen delivery based on the on-demand decomposition of ammonia.

The main achievements:
• The rector monoliths with embedded Fe-based magnetic nanoparticles heated up to 200 °C under alternating magnetic field.
• The reactor monoliths with embedded Co/Ni magnetic nanoparticles heated up to 650 °C.
• Catalytical tests were conducted by utilizing Co/Ni-based reactor monoliths resulting in 87% ammonia degradation with ammonia flow of 30 cm3 min−1 and 73 % degradation with ammonia flow of 60 cm3 min−1 at 600 °C in both cases.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Scientific impact:
• The complex shaped reactor monolith was successfully fabricated exhibiting on demand heating up to 650°C when exposed to the alternating magnetic field. Such monolith reactor when coated with a suitable catalyst is capable for performing various catalytical process. The verification of this approach was conducted with ammonia degradation to obtain a hydrogen which could be then used as a fuel. The further optimization of the process is needed to fully utilize the capabilities of the proposed monolith reactor. Primarily, introducing of a new catalyst material, that can operate at significantly lower temperatures. These advancements could reduce both energy consumption and system costs while maintaining high conversion efficiency. The produced hydrogen could be used to supply fuel cell system resulting in decentralized use of green ammonia.
• Ammonia degradation is a crucial technology for the European Green Deal, acting as a missing link in the global hydrogen supply chain.
• The potential end use of the project results could be hydrogen refueling station. Such hydrogen could be burned in internal combustion engines for motive transport or remote power generation. Blending hydrogen with traditional hydrocarbon fuels is also possible. The suitable communication with partners from industry is still pending.