Preparation of CuO/SBA-15 catalyst by the modified ammonia driven deposition precipitation method with a high thermal stability and an efficient automotive CO and hydrocarbons conversion

Abstract Copper oxide (CuO) loaded heterogeneous catalysts are a potential candidate to replace the critical precious metals Pt and Pd for the automotive oxidation reaction. However, a good CuO dispersion on the supports is necessary to compensate for its low intrinsic activity. Moreover, regarding the high operating temperature within the vehicle, a strong metal-support interaction is also required for providing a high thermal resistance to the catalyst. In this work, a series of CuO loaded SBA-15 catalysts has been prepared according to a modified ammonia driven deposition precipitation method (ADP). Herein, the Cu/NH 3 ratio of the synthesis has been varied with the aim to assess its influence on the CuO particles dispersion and CuO-support interaction. The morphology and porosity of the catalysts, the copper oxide dispersion and the chemical state of CuO were characterized and compared by a combination of techniques. In addition to this, the catalysts’ thermal stability and their performance towards the automotive emission control have also been addressed. Results demonstrated that the ADP method is an efficient and scalable approach to fabricate a copper oxide based catalyst with a distinct automotive oxidation activity. Furthermore, it has been shown that, when a higher Cu/NH 3 ratio has been applied, a higher copper oxide dispersion degree can be achieved which has a strong metal-support interaction. The latter feature leads to its excellent thermal stability up to 700 °C, accompanied with a prolonged catalytic life-span in comparison with the conventional wet impregnation approach