Removal of CO from pre-combustion CO₂ rich streams using chemical looping technology
article
Complying with CO2 purity specifications is unavoidable for any carbon capture technology due to technical, economic, and safety requirements for transportation, storage, and utilization. The tolerated impurity levels can be stringent, leading to a significant increase in capture costs. Depending on the applied technology and the flue gas source, different impurities are present. This study focuses on pre-combustion capture CO2 purification, in particular removing CO using chemical looping technology. Compared to existing CO removal methods, chemical looping can remove CO with reduced energy penalty while at the same time improve the CO2 recovery and remove other impurities like H2 and CH4 which might be present in pre-combustion CO2 captured stream. The feasibility of applying chemical looping for deep CO removal (<100 ppm) was first evaluated thermodynamically, considering various oxygen carriers like Ni, Cu, Mn, and Fe. Promising redox couples identified include Cu2O/Cu and Fe2O3/Fe3O4, while nickel and manganese based oxides showed less potential. Both reduction and regeneration are exothermic, offering opportunities for heat recovery. Iron-based oxygen carriers were further evaluated experimentally, showing excellent performance and stability over ∼200 cycles at 400–550 °C for a 20wt%Fe2O3 impregnated on Al2O3 sample. Higher temperatures showed increased conversion up until 450 °C. Optimal operating temperatures should consider process design and economics, including heat integration options. CO2 purification by chemical looping appears to be an attractive CO removal technology. © 2026 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license. http://creativecommons.org/licenses/by-nc-nd/4.0/
TNO Identifier
1029233
DOI
https://dx.doi.org/10.1016/j.ijggc.2026.104612
ISSN
17505836
Source
International Journal of Greenhouse Gas Control, 151.0, pp. 1-16.
Publisher
Elsevier Ltd
Pages
1-16