Promotion of ZrO₂ on RuO₂/Al₂O₃ Catalyst for HCl Catalytic Oxidation: Effect of High Temperature Holding in Nitrogen Atmosphere

Catalytic oxidation of HCl to Cl2 to realize chlorine recycling is an inevitable requirement for the sustainable development of chlorine-related industries. In this paper, RuO2/ZrO2–Al2O3 was prepared by loading ZrO2 and RuO2 successively on the commercial Al2O3 carrier, followed by further high temperature holding in nitrogen. The XRD, XPS, H2-TPR, and TEM results show that after high temperature holding, both the morphology of RuO2 and ZrO2 transformed from three-dimensional nanoparticles to two-dimensional plates on Al2O3. As a result, the dispersity of Ru was obviously improved, RuO2(110) crystal plane was fully exposed, and Zr atoms entered the RuO2 lattice to form RuxZryOz species which changed the lattice parameters of RuO2, finally leading to the obviously improved activity and stability in HCl catalytic oxidation reaction.