Highly Efficient Oxygen-Storage Material with Intrinsic Coke Resistance for Chemical Looping Combustion-Based CO2 Capture.
Chemical looping combustion (CLC) and chemical looping with oxygen uncoupling (CLOU) are emerging thermochemical CO2 capture cycles that allow the capture of CO2 with a small energy penalty. Here, the development of suitable oxygen carrier materials is a key aspect to transfer these promising concepts to practical installations. CuO is an attractive material for CLC and CLOU because of its high oxygen-storage capacity (20 wt %), fast reaction kinetics, and high equilibrium partial pressure of oxygen at typical operating temperatures (850-1000 °C). However, despite its promising characteristics, its low Tammann temperature requires the development of new strategies to phase-stabilize CuO-based oxygen carriers. In this work, we report a strategy based on stabilization by co-precipitated ceria (CeO2-x ), which allowed us to increase the oxygen capacity, coke resistance, and redox stability of CuO-based oxygen carriers substantially. The performance of the new oxygen carriers was evaluated in detail and compared to the current state-of-the-art materials, that is, Al2 O3 -stabilized CuO with similar CuO loadings. We also demonstrate that the higher intrinsic oxygen uptake, release, and mobility in CeO2-x -stabilized CuO leads to a three times higher carbon deposition resistance compared to that of Al2 O3 -stabilized CuO. Moreover, we report a high cyclic stability without phase intermixing for CeO2-x -supported CuO. This was accompanied by a lower reduction temperature compared to state-of-the-art Al2 O3 -supported CuO. As a result of its high resistance towards carbon deposition and fast oxygen uncoupling kinetics, CeO2-x -stabilized CuO is identified as a very promising material for CLC- and CLOU-based CO2 capture architectures.
Laboratory of Energy Science and Technology, ETH Zurich, Leonhardstrasse 27, 8092 Zurich (Switzerland).
Qasim
Q
Imtiaz
Laboratory of Energy Science and Technology, ETH Zurich, Leonhardstrasse 27, 8092 Zurich (Switzerland).
Alexey
A
Kurlov
Electrochemical Materials, ETH Zurich, Hönggerbergring 64, 8093 Zurich (Switzerland).
Jennifer Lilia Marguerite
JL
Rupp
Laboratory of Energy Science and Technology, ETH Zurich, Leonhardstrasse 27, 8092 Zurich (Switzerland). muelchri@ethz.ch.
Christoph Rüdiger
CR
Müller
D000537:Aluminum Oxide / Q000737:chemistry; D002245:Carbon Dioxide / Q000737:chemistry* / Q000302:isolation & purification*; D002563:Cerium / Q000737:chemistry; D003077:Coke; D003300:Copper / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D013696:Temperature
D003077:Coke; D002245:Carbon Dioxide; D002563:Cerium; C030583:ceric oxide; D003300:Copper; D000537:Aluminum Oxide; D010100:Oxygen; C030973:cupric oxide
carbon dioxide capture; cerium; chemical looping; copper; materials science