Citrate complexation microwave-assisted synthesis of Ce0.8Zr0.2O2 nanocatalyst over Al2O3 used in CO oxidation for hydrogen purification: influence of composite loading and synthesis method

Abstract

In this research, nanostructured Ce_0.8Zr_0.2O₂/Al₂O₃ composite catalysts were synthesized by a modified citrate complexation method with different loadings of active phase and support. The modification was carried out by impregnation and microwave-combustion techniques. XRD, FESEM, EDX, BET, FTIR and TPR-H₂ have been used for characterization of nanocatalysts. Utilizing a microwave-assisted combustion method, we created a sample with a more uniform and homogenous pattern, leading to better catalytic properties and more available lattice oxygen toward CO oxidation. According to the reactor test, it was found that the support has a strong influence on the activity of the catalysts. Generally, between citrate modified by impregnation, addition of alumina up to 40 wt% enhanced the dispersion of the active phase and greatly improved the catalytic activity of the catalyst. The composition that performed the best in the reactor test was Ce_0.8Zr_0.2O₂ (40 wt%)/Al₂O₃, which was synthesized by a citrate complexation microwave-assisted combustion method.