Integrated CO2 Capture and Hydrogen production.



An integrated process concept is proposed for low-cost, post-combustion CO2 capture and renewable H2 production, with O2 co-generation. The core innovation intensifies electrolysis of aqueous electrolyte that contains (bi)carbonate, as output stream from the aqueous KOH-based capture step. By this way, no dedicated ‘stripping’ energy is required, KOH capture agent is regenerated together with H2 evolution and O2/CO2 valorised via oxy-fuel combustion and H2-mediated CO2 conversion, respectively after separation.

In the ICO2CH project, an integrated concept is investigated for the low-cost capture from CO2 point sources with alkaline KOH-based media and renewable H2 production. The innovation is on the level of the water electrolyser, which is fed by a CO2-rich, post-capture (bi)carbonate solution, that enables isolation of a 80:20 % CO2/O2 gas mixture from the anolyte during operation. This eliminates the need for dedicated ‘stripping’ energy, since CO2 liberation is a consequence of OH- consumption during O2 production. Simultaneously, KOH is regenerated in the Hevolution reaction, avoiding further capture utility costs. The high-purity COstream can be valorized, in combination with H2 to produce e.g. synthetic fuels, next to Oin (partial) oxy-fuel combustion, after a final CO2/O2 separation step.

The scientific goals are related to performance targets that enable low electrolyser cost levels (CAPEX ~current density, AWE: 600 - 1200 €/kW) with minimal impact on OPEX (electricity use/efficiency ~cell potential). This will be pursued by the development and stacking of 3D-thin-film components (VITO – Imec), to (1) compensate decreased ionic conductivities compared to typical KOH-based electrolytes and (2) maximize the effectiveness of pH change at the anodic side. Therefore multiphase models are used to link electrochemical reactions and transport phenomena to the bulk chemistry, while process modeling and application testing is involved in the evaluation of CO2/O2 separation (VUB) and integration with an oxy-fuel combustion step (KUL). The project is supported by research-directive models and advice (VITO), based on techno-economic principles and benchmark analysis.

The key exploitable results encompass devices and process-based innovations, addressing producers of electrocatalysts, electrodes and membranes, next to process developers, for valorization. The end users of such capture technology are present in the refining, chemical, steel and energy sectors, having unavoidable CO2 point source emissions and optionally interest in (partial) oxy-fuel combustion. This also involves companies (or clusters) interested in CCU/Power-to-X applications with access to high-purity CO2 and H2, as produced in one intensified system.

Project details

Project type
ESI Project
Research trajectory
Project status
Approved on
Project date
€2 517 968

Project Partners