DMC Formation over Ce0.5Zr0.5O2 Prepared by Complex-decomposition Method

Abstract

The Ce0.5Zr0.5O2 solid solution was prepared by a complex-decomposition method using different organic acids as complexants and cerium and zirconium nitrides as precursors, respectively. The characterization results of XRD, Raman, SEM, H2-TPR, CO2-TPD, N2 adsorption at 77 K indicate that the physical properties of the solid solutions were significantly affected by the complexants used. These solid solutions can be used in dimethyl carbonate (DMC) synthesis from methanol and CO2. Results indicate that crystal structure of Ce0.5Zr0.5O2 was the key factor in determining the catalytic activity for DMC synthesis. Moreover, the catalytic activity of the Ce0.5Zr0.5O2 was significantly decreased when phase separation as a result of the enrichment either of Ce or Zr was occurred. The BET surface area, the redox behavior, and pore properties of the solid solution, depending on the complexants used and the calcination temperature, also played less important roles in determining the catalytic activity for the titled reaction. The optimized Ce0.5Zr0.5O2 showed high activity for the direct synthesis of DMC from CO2 and methanol.