CuO-CeO2 catalysts based on SBA-15 and SBA-16 for COPrOx. Influence of oxides concentration, incorporation method and support structure

In this work different variables that can affect the catalytic behavior of CuO-CeO2 supported on mesoporous silica (SBA-15 and SBA-16) were studied. The influence COPrOx activity relative concentration CuO CeO2 active phase impregnation methods in support was analyzed. physicochemical characterization performed EDS-SEM TEM-STEM, N2 isotherms, X-ray Diffraction (XRD) Photoelectron Spectroscopy (XPS). incipient wetness method (IWI) better alternative to introduce phases compared solid state (SSI). addition, catalysts based 2-D structure SBA-15 more selective than those 3-D SBA-16. general, high surface area supports benefited dispersion oxides nanoparticles. All displayed preservation mesostructure formation nanoparticles (less 10 nm) detected by TEM. best catalyst, obtained from fibers IWI method, with a 0.2, exhibited XCO ? 99% at 175 °C above 90% wide window temperatures. This catalyst showed an adequate performance presence CO2 H2O good recovery CO conversion selectivity. analysis XPS revealed majority species Ce4+, however some Ce3+ are also present, which associated vacancies oxygen favor redox process. Cu2+ Cu+ latter recognized as key site adsorption reaction mechanism.