Infopack #1: Proton ceramic reactor stack design

1 INFO-PACK #1 • PROTON CERAMIC REACTOR STACK DESIGN Five Functions, One Membrane: SINGLE Project successful move from single cell to full stack Introduction Proton ceramic reactor stack design SINGLE revolves around using a proton ceramic electrochemical reactor (PCER) to crack ammonia and extract hydrogen. The compact and modular system combines ammonia dehydrogenation (ADH), hydrogen separation, and electrochemical compression into a single, highly efficient process. Previously demonstrated at the single cell level (4 cm tube-shaped reactor), this paper documents the project’s successful move to a functional stack design incorporating 36 cells. The design electrically connects 6, 6-cells barrels using a glass-ceramic–Ni composite interconnect and integrated glass-ceramic sealant. The barrels and stacks are assembled using innovative key enabling technologies such as interconnects, conductive washers, gas manifolds, and seals. The ammonia resistance of each component was particularly looked at to ensure stability over time. Twenty PCER stacks are in production for SINGLE and intended to be used in the dedicated 10 kg H₂/day pilot plant located near Valencia, Spain. ABSTRACT Hydrogen is incredibly challenging to transport over long distances, hydrogen molecules are small and can cause embrittlement in metal pipelines, leading to safety risks and the need for costly material upgrades. To solve this issue, ammonia is considered a promising hydrogen carrier due to its ease of handling and transport (gas at ambient temperature, liquid at -33°C and 1 bar). The SINGLE project is demonstrating a solution for the later stage of this hydrogen transport value chain: retrieving hydrogen from ammonia. SINGLE revolves around using a proton ceramic electrochemical reactor (PCER) to crack ammonia (Ammonia Dehydrogenation, ADH) and extract hydrogen. The compact and modular system combines ADH, hydrogen separation, and electrochemical compression into a single, highly efficient process. The project’s aim is to develop and demonstrate the technology at pilot scale (TRL5) in a demonstration plant near Valencia, Spain. In this document we are presenting the successful production and demonstration of on the core elements of the SINGLE project: the proton ceramic reactor stack design (PCER stack). Key points • Introduction of an innovative tubular cell reactor design • Scaled-up operation demonstrated with ammonia feed • Technology to reach TRL5 in 2026 Related KERs or Info-packs • Info-packs #1 to #3 INFO-PACK #1 2 INFO-PACK #1 • PROTON CERAMIC REACTOR STACK DESIGN Five Functions, One Membrane: An innovation in Ammonia-to-Hydrogen Conversion The stack design is based on a tubular cell architecture and the basic design of the stack concept and operating principle is illustrated in the Figure 1. The electrochemically driven PCER stack technology realizes five process steps simultaneously within a 400 μm length scale: • The Ni-BZCY porous support provides catalytic activity toward ADH; • It extracts hydrogen from the ADH side and shifts a thermodynamically limited reaction sequence toward full conversion of ammonia; • It delivers heat to the endothermic reaction through the electrical operation of the membrane; • It compresses hydrogen directly at the sweep side of the membrane; • It produces high-purity hydrogen. The combination of these functions in a single, spatially integrated stage confers high overall energy efficiency, process simplicity, and compactness. Figure 1: Operating principle of the stack. The geometric configuration, an important aspect of the PCER design compared to the planar alternatives, allows for pressurized operation and improved robustness against thermal gradients and thermal runaway propagation. This was explored experimentally at the cell level and through simulation at the stack level, in a Science publication1. In the publication, ammonia conversion >97% was demonstrated at open-circuit conditions and nearly 100% conversion at high H₂ recoveries, leaving an effluent stream virtually free of residual NH₃. 3 INFO-PACK #1 • PROTON CERAMIC REACTOR STACK DESIGN From Simulation to Reality: First Fully Functional ADH PCER Stack Proven A first PCER stack for ammonia dehydrogenation was successfully produced in SINGLE. It has 6 barrels (as seen in Figure 2) electrically connected in series using a glass-ceramic–Ni composite interconnect and integrated glass-ceramic sealant. Each barrel contains 6 tubular proton ceramic-based cells. The cells are based on a Ni-BZCY electrode support (anode), BZCY electrolyte, and an outer Ni-BZCY electrode (cathode). The anode also acts as the catalyst for the ADH reaction. The barrels and stacks are assembled using other key enabling technologies such as interconnects, conductive washers, gas manifolds, and seals. Figure 2: Barrels stack design as envisioned for the SINGLE project and developed by CTMS. A multiphysics simulation of a multi-segmented PCER stack confirmed efficient operation under ADH conditions, as reported in a recent Science publication. During the SINGLE project, these findings were successfully validated. A PCER stack was tested and validated at two partner institutions: CoorsTek Membrane Science (CTMS) and Instituto de Tecnología Química (ITQ, UPV-CSIC) facilities. The 36-cell PCER stack achieved 99% ammonia conversion and high H₂ recoveries (> 98%) at 750°C and 10 bar operating conditions. Furthermore, the system demonstrated continuous and stable operation for over 100 hours—successfully meeting one of the project’s critical milestones and proving the viability of PCER stack performance at scale. 4 INFO-PACK #1 • PROTON CERAMIC REACTOR STACK DESIGN From Prototype to Pilot: Quality-Driven Manufacturing of 20 PCER Units Conclusions Modular by Design, Built for Impact The Road to Industrial Integration Based on this success, 20 proton ceramic reactor stacks are in production for SINGLE and intended to be used in the dedicated 10 kg H₂/day pilot plant located near Valencia, Spain. The project is using existing fabrication routes at CTMS. Components of the original PCER stack, as well as additional ones developed for ammonia operation, are produced using CTMS quality control (QC) system and are following defined specifications elaborated in the context of SINGLE. The next step for the PCER STACKs is testing them in a scaled-up TRL5 pilot plant, marking a key milestone toward industrial integration. Twenty stacks will be produced and placed into a controlled heat-enclosure in Oslo. The enclosure will be then shipped to Spain to be installed into the Spain-produced BoP and will constitute the demo plant intended to produce 10 kg a day of hydrogen. Consortium members view SINGLE stacks-based technology as well-suited for commercial deployment. Thanks to its intrinsically modular design which allows for small-scale implementation that can grow with rising demand, it complements historical fixed largescale incumbent technologies in applications where they fall short due to cost or deployment practicalities. This flexibility enables the system to address a wide range of use cases and would represent a major advancement toward making ammonia a commercially competitive hydrogen carrier. In SINGLE, the development of the Proton Ceramic Electrochemical Reactor (PCER) stack has progressed rapidly from concept to reality. Building on promising results from Coorstek Membrane Sciences at the cell level, a first fully functional ADH PCER stack was successfully produced and tested, validating the performance of the integrated multi-barrel design. Following this milestone, production is now ramping up to deliver 20 new stacks demonstrating the ability to manufacture high-quality reactors reliably through a robust, QC-enabled fabrication process. The 20 PCER stacks will be integrated in a TRL5 pilot-scale testing. This demo plant is designed to produce 10 kg of hydrogen per day and serves as a crucial step toward industrial implementation. Thanks to their inherently modular and scalable design, the SINGLE stacks offer a flexible, cost-efficient alternative to traditional large-scale hydrogen production methods, positioning ammonia as a viable and commercially competitive hydrogen carrier for diverse applications. 5 INFO-PACK #1 • PROTON CERAMIC REACTOR STACK DESIGN Authors Bibliography Gautier Papon Project Director at CoorsTek Membrane Science AS [email protected] Selene Hernández Morejudo Research Director at CoorsTek Membrane Science AS [email protected] Sonia Escolástico, Tenured Scientist at Instituto de Tecnología Química Universitat Politècnica de València, Consejo Superior De Investigaciones Científi cas [email protected] Fidel Toldrá Reig Post-doctoral Researcher at Instituto de Tecnología Química Universitat Politècnica de València, Consejo Superior De Investigaciones Científi cas fi tolr[email protected]v.es 1 Clark, D., et al., Single-step hydrogen production from NH3, CH4, and biogas in stacked proton ceramic reactors. Science, 2022. 376(6591) : p. 390-393 Co-funded by the European Union, the Clean Hydrogen Partnership and its members Hydrogen Europe and Hydrogen Europe Research. Views and opinions expressed are those of the author(s) only and do not necessarily reflect those of the European Union or Clean Hydrogen Partnership. Neither the European Union nor the granting authority can be held responsible for them.  singleh2.eu  [email protected]  SINGLE H2 PROJECT