Insight into the effects of calcination temperature on the structure and performance of RuO2/TiO2 in the Deacon process

Abstract

Rutile-type TiO₂ supported RuO₂ (RuO₂/TiO₂) catalysts show a remarkable low-temperature activity and a long lifetime and have been industrially applied in the oxidation of HCl with O₂ to Cl₂, i.e., the Deacon process. The calcination of the as-prepared samples is crucial for the catalytic performance of the resultant catalysts. However, the effects of calcination temperature on the structure and performance of RuO₂/TiO₂ catalysts have not been systematically investigated yet. In the present work, several RuO₂/TiO₂ catalysts were prepared via a dry impregnation method and subsequently calcined at different temperatures. Various techniques were then employed to characterize the RuO₂/TiO₂ catalysts that were evaluated in the Deacon process. The results show that the structure and performance of these Deacon catalysts is closely related to the calcination temperature for the catalyst preparation. The resultant RuO₂/TiO₂ catalyst from a calcination temperature of 250 °C shows the highest catalytic activity due to RuO₂ being well dispersed on TiO₂, leading to the largest amount of surface RuO₂. The current study, therefore, not only elucidates the effects of calcination temperature on the structure and performance of RuO₂/TiO₂ catalysts but also provides some guidance for developing an efficient catalyst in the Deacon process.