Mechanochemical Synthesis of Co/ZnO/Al2O3 Oxide Composite for Catalytic Systems

Abstract

The process of soft mechanochemical synthesis of CuO/ZnO/Al₂O₃ composites using copper/zinc hydroxocarbonates and alumina as starting materials was studied. The regularities occurring at the stage of mechanochemical activation and sucsequent thermal treatment were investigated by means of x-ray diffraction (XRD) and synchronous thermal analysis methods. The influence of the energy intensity of the mill on the textural properties of the composite was demonstrated. Low-temperature nitrogen adsorption-desorption showed that in the process of mechanochemical synthesis the total specific surface area of the samples changes insignificantly, while the type of processing has a significant effect on textural properties including pore size distribution, active surface area, and copper dispersion. Temperature ranges of composite activation for catalytic applications were obtained by the method of thermo-programmed reduction. The positive influence of the mechanical activation on the formation of the composite structure was observed. This allows its use as the main component of the catalyst for the production of ammonia, hydrogen, and methanol.