Articles
  • Effect of Ce0.9Gd0.1O1.95 as a promoter upon the oxygen transfer properties of MgMnO3-δ-Ce0.9Gd0.1O1.95 composite oxygen carrier materials for chemical looping combustion
  • Jong Ha Hwanga and Ki-Tae Leeb,c,*
  • aDepartment of Mineral Resources & Energy Engineering, Chonbuk National University, Jeonbuk 54896 Korea bDivision of Advanced Materials Engineering, Chonbuk National University, Jeonbuk 54896 Korea cHydrogen and Fuel Cell Research Center, Chonbuk National University, Jeonbuk 54896 Korea
Abstract
Chemical looping combustion (CLC) is a promising carbon capture and storage (CCS) technology whose efficiency and cost primarily relies on the oxygen carrier materials used. In this paper, gadolinium-doped ceria (GDC, Ce0.9Gd0.1O1.95) was added as a promoter to improve the oxygen transfer rate of MgMnO3-δ oxygen carrier materials. Increasing GDC content significantly increased the oxygen transfer rate of MgMnO3-δ-GDC composites for the reduction reaction due to an increase in the surface adsorption of CH4 via oxygen vacancies formed on the surface of the GDC. On the other hand, the oxygen transfer rate for the oxidation reaction decreased linearly with increasing GDC content due to the oxygen storage ability of GDC. Adsorbed oxygen molecules preferentially insert themselves into oxygen vacancies of the GDC lattice rather than reacting with (Mg,Mn)O to form MgMnO3-δ during the oxidation reaction.

Keywords: Chemical looping combustion, Oxygen carrier material, Re-dox reaction, Oxygen transfer capacity, Oxygen transfer rate

This Article

  • 2019; 20(1): 18-23

    Published on Feb 28, 2019