OPEN ACCESS

Articles online

The Effect of the Support Structure and Size of Cu-based Oxygen Carriers on the Performance of Chemical Looping Air Separation

Category: Aerosol Physics and Instrumentation

Volume: 20 | Issue: 3 | Pages: 544-556
DOI: 10.4209/aaqr.2019.06.0310
PDF

Export Citation:  RIS | BibTeX

To cite this article:
Wang, H.C., Lee, H.H., Chang, M.H., Wan, H.P., Cheng, J.Y. and Wu, T.Y. (2020). The Effect of the Support Structure and Size of Cu-based Oxygen Carriers on the Performance of Chemical Looping Air Separation. Aerosol Air Qual. Res. 20: 544-556. doi: 10.4209/aaqr.2019.06.0310.

Hou-Chuan Wang , Hsiu-Hsia Lee, Ming-Hui Chang, Hou-Peng Wan, Jui-Yen Cheng, Ting-Yi Wu

  • Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu 31040, Taiwan

Highlights

  • Evaluation on the support structure and size of OC for CLAS was performed.
  • CuZr-IM OC exhibited complete conversion and fast reaction rate.
  • The activation energy of CuZr-IM OC during reduction in CLAS was 140.2 kJ mol–1.
  • The CuZr-IM OC maintained relatively stable conversion during redox reaction.

Abstract

Chemical looping air separation (CLAS) is a novel and efficient method of producing high-purity oxygen because of its low-energy demands. Cu-based materials are suitable oxygen carriers (OCs) for CLAS. In the current study, Cu-based OCs in different particle sizes were prepared using various methods (viz., through mechanical mixing, impregnation, and coprecipitation) and different supporting materials (viz., ZrO2, SiO2, and Al2O3) and porosities (viz., in the mesopore range). This study evaluated the reactivity, reaction kinetics, and recyclability of these OCs by measuring their conversion rates for reduction (oxygen release) and oxidation (regeneration) in a thermogravimetric analyzer. CuO OCs on ZrO2 nanoparticles prepared through impregnation (CuZr-IM) exhibited almost complete conversion and the fastest reaction rates of all the OCs for reduction and oxidation. These characteristics are primarily attributable to the fine particles (100–250 nm) of the OCs. Furthermore, the CuO on the surface of the ZrO2 particles was distributed in a uniform pattern, as these fine particles displayed greater oxygen mobility and more rapid diffusion than the micrometer-sized particles paired with bulk materials. Kinetic analysis revealed that Avrami-Erofe’ev random nucleation and the subsequent growth reaction model with n = 2 (A2), with an observed activation energy of 140.2 kJ mol–1 in our study, is the optimal fitting for CuZr-IM OC conversion during reduction, and a long-term-stability test indicated that this OC is an appropriate candidate for CLAS.

Keywords

Chemical looping Oxygen carrier Oxygen CuO/ZrO2 Kinetics Mechanism


Related Article

;