Aluminum-based ozone catalysts prepared by mixing method: Characteristics, performance and carbon emissions

Green and low carbon is an essential direction for the development of water treatment technology. Ozone catalysts prepared by the mixing method have advantages in terms of energy consumption and CO₂ emissions, but are considered to be insufficient in catalytic efficiency and stability. In this paper, an Mn-Cu-Ce/Al₂O₃ (MCCA) catalyst was prepared by optimizing the preparation conditions of the mixing method and the types and ratios of active components. Taking petrochemical secondary effluent (PCSE) as the treatment object, the performance of the catalyst and the carbon emission in the preparation process were studied; and compared with the impregnation method. Results showed that compared with catalysts loaded with other components, the MCCA had a higher removal efficiency for TOC (43.04%) and COD (53.18%), which was basically equivalent to the impregnation method, and the treated effluent reached the expected concentration. MCCA promoted the decomposition rate of O₃ by ten times, and the main active species generated were found to be •OH and ¹O. Similar to the catalytic ozonation by the catalyst prepared by the impregnation method, the adsorption sites and surface hydroxyl groups on the MCCA surface play a significant role in the degradation of pollutants. However, the carbon emission in the catalyst preparation process of the mixing method was 418.68 kg/ton, which was only 44% of the impregnation method (949.67 kg/ton). Under the global low-carbon transition, this study shows that the mixing method aligns more with the concept of green, clean, and efficient ozone catalyst preparation.