Periodic Reporting for period 2 - ANEMEL (ANion Exchange Membrane Electrolysis from Low-grade water sources)
Reporting period: 2023-09-01 to 2025-02-28
Green hydrogen production is one of the key elements in the energy transition. Fluctuating renewable energy sources require of suitable energy vectors that can balance supply and demand, and it is very challenging to find suitable energy storage options. Hydrogen, even with its own challenges, can provide a solution for seasonal and large-scale storage of renewable energies as well as become a key element for sector coupling. For the production of green hydrogen, two abundant resources are required, renewable energy and water. Considering that water resources are limited for human consumption, to achieve a large-scale use it is important to find sources of water that do not compete with drinking water.
ANEMEL aims at the development of an anion exchange membrane electrolyzer that operates using low-grade water sources such as saline and wastewater, to produce green hydrogen using renewable sources. The project will achieve this objective by focusing on the preparation of selective and efficient membrane electrode assemblies using non-critical raw materials as electrocatalysts and membranes. The expertise of the consortium in oxygen and hydrogen evolving electrocatalysts, membrane preparation, reactor engineering and reactor modelling will ensure the delivery of an AEM device capable to operate at low overpotentials, without major water pre-treatment and at a current density above 1 A cm-2.
The technical work will be compemented with an ecodesign process supported by an environmental and socio-economic analysis to guide the development of a low impact and circular designed AEM device maximising socio-economic benefits. A techno-economic and exploitation plan to move from laboratory scale single-cell to a multi-stack electrolyser will be studied to ensure a fast-track to commercialisation.
ANEMEL aims at the development of an anion exchange membrane electrolyzer that operates using low-grade water sources such as saline and wastewater, to produce green hydrogen using renewable sources. The project will achieve this objective by focusing on the preparation of selective and efficient membrane electrode assemblies using non-critical raw materials as electrocatalysts and membranes. The expertise of the consortium in oxygen and hydrogen evolving electrocatalysts, membrane preparation, reactor engineering and reactor modelling will ensure the delivery of an AEM device capable to operate at low overpotentials, without major water pre-treatment and at a current density above 1 A cm-2.
The technical work will be compemented with an ecodesign process supported by an environmental and socio-economic analysis to guide the development of a low impact and circular designed AEM device maximising socio-economic benefits. A techno-economic and exploitation plan to move from laboratory scale single-cell to a multi-stack electrolyser will be studied to ensure a fast-track to commercialisation.
During the first year of the project, significant advances have been made to develop own components for an AEM electrolyzer that can operate at alkaline conditions. Some components have also been tested and shown promising results under saline conditions, and more challenging electrolytes (close to neutral pH and saline water) will be the focus of the next period of the project.
In particular, OER and HER electrocatalysts made of non-CRM or non-PGM (more relevant term from now on) have been synthesised and initial physico-chemical and electrochemical characterisations have been made. Some of the catalyst show very promising activity at the targeted electrolytes, and some of the electrocatalysts have also been tested in single-cell electrolysers under alkaline conditions, achieving excellent stability over long-term experiments.
Head groups for the anion exchange polymers have been prepared, showing very good stability and suitable ionic conductivity. In parallel, reinforced membranes have been synthesised and characterised, achieving the targeted mechanical strength. With the addition of suitable radical scavengers to improve chemical resistance, some suitable membranes have been prepared and will be shared to other ANEMEL partners to incorporate into single-cell and stack devices.
In the second reporting period, efforts have been focused on the further development of non-PGM OER and HER electrocatalysts capable to operate under the challenging electrolyte conditions mentioned in the project. The most promising catalysts have been deposited on electrode surfaces and tested in single-cell water electrolysers, achieving the target milestone of 1 A cm-2 at 2 V within the pH range 7-12.
The work on polymers and head groups have continued with the development of components with excellent stability under mild alkaline conditions. Preliminary tests show even better stability in saline conditions as expected since the oxidative degradation is less pronounced.
Finally, the work on the electrolyser stack has continued with the development and testing of the test station, and validation of a new patented flow pattern using commercially available components.
In particular, OER and HER electrocatalysts made of non-CRM or non-PGM (more relevant term from now on) have been synthesised and initial physico-chemical and electrochemical characterisations have been made. Some of the catalyst show very promising activity at the targeted electrolytes, and some of the electrocatalysts have also been tested in single-cell electrolysers under alkaline conditions, achieving excellent stability over long-term experiments.
Head groups for the anion exchange polymers have been prepared, showing very good stability and suitable ionic conductivity. In parallel, reinforced membranes have been synthesised and characterised, achieving the targeted mechanical strength. With the addition of suitable radical scavengers to improve chemical resistance, some suitable membranes have been prepared and will be shared to other ANEMEL partners to incorporate into single-cell and stack devices.
In the second reporting period, efforts have been focused on the further development of non-PGM OER and HER electrocatalysts capable to operate under the challenging electrolyte conditions mentioned in the project. The most promising catalysts have been deposited on electrode surfaces and tested in single-cell water electrolysers, achieving the target milestone of 1 A cm-2 at 2 V within the pH range 7-12.
The work on polymers and head groups have continued with the development of components with excellent stability under mild alkaline conditions. Preliminary tests show even better stability in saline conditions as expected since the oxidative degradation is less pronounced.
Finally, the work on the electrolyser stack has continued with the development and testing of the test station, and validation of a new patented flow pattern using commercially available components.
The expected technical KPIs have been achieved for the "less challenging" electrolyte, 1 M KOH. We have designed and assembled a first stack which achieves a power output exceeding the 1kWe as targeted in the project.
Further work needs to be done with the more challenging electrolyte conditions of 0.01 M KOH, DI water and 0.5 M NaCl. More selective OER/HER electrocatalysts are required to avoid the formation of chlorine evolution reaction products. Also, suitable engineering and chemistry needs to be found for the anion exchange membrane to operate under a chloride electrolyte.
Based on the results so far, we have identified three promising innovations (as shows in the radar) that will be further researchers in the next 2 years.
In the second reporting period, several new OER and HER electrocatalysts and membranes have been developed showing excellent results. Several new peer-reviewed publications demonstrated the high impact of the work, with record performance in terms of achieved current density and stability. In addition, the patent of the stack clearly indicated the potential commercialisation of the ANEMEL technology beyond the project.
Further work needs to be done with the more challenging electrolyte conditions of 0.01 M KOH, DI water and 0.5 M NaCl. More selective OER/HER electrocatalysts are required to avoid the formation of chlorine evolution reaction products. Also, suitable engineering and chemistry needs to be found for the anion exchange membrane to operate under a chloride electrolyte.
Based on the results so far, we have identified three promising innovations (as shows in the radar) that will be further researchers in the next 2 years.
In the second reporting period, several new OER and HER electrocatalysts and membranes have been developed showing excellent results. Several new peer-reviewed publications demonstrated the high impact of the work, with record performance in terms of achieved current density and stability. In addition, the patent of the stack clearly indicated the potential commercialisation of the ANEMEL technology beyond the project.