Abstract:
In this research, the effect of characteristics of zirconia and metal oxide modified zirconia catalysts on the catalytic performance were investigated by ketonic decarboxylation of methyl stearate to desired ketone product at the optimal condition (400°C and 1 bar). Zirconia and metal oxide modified zirconia catalysts were characterized by using X-ray diffraction (XRD), Scanning electron microscope (SEM), N2-physissorption, X-ray photoelectron spectroscopy (XPS), and IR spectra of pyridine adsorption (Pyridine-IR). The results indicated that the transition metal oxide group modified zirconia catalysts have higher contents of total Lewis acid site and oxygen vacancies site, and lower content of total Brønsted acid site on the surface of catalysts, which provides high conversion and high selectivity. For the comparison of the Lewis and Brønsted acid site,and oxygen vacancies site, it can be concluded that the conversion of methyl stearate only depends on Lewis acid site. Furthermore, Brønsted acid site affecting selectivity as well as oxygen vacancies site, but the Brønsted acid site plays an important role in the selectivity of desired ketone product more than the oxygen vacancies site.
