Surface Properties and Reactivity of Iron-Doped Titanium Oxides Catalysts in Oxidative Dehydrogenation of Ethylbenzene with CO2

Abstract

The effect of Fe³⁺ doping level on the surface properties and catalytic performance of a series of iron-doped titanium oxide catalysts (1–7 mol% Fe³⁺) prepared using an acid-catalyzed sol-gel method was investigated in oxidative dehydrogenation of ethylbenzene with CO₂. The characterization of catalysts was carried out by means of x-ray powder diffraction (XRD), temperature programmed reduction (TPR), and the method of Brunauer, Emmett, and Teller (BET). It was found that the capacity of isolated Fe³⁺ centers in titania matrix is responsible for the catalytic performance; the catalysts exhibit the best activity at the loading level of Fe³⁺, about 3 mol%. In addition, it was shown that the appropriate pore size of the catalysts ranges from 5 nm to 25 nm; the selectivity to styrene increases with an increase in the specific surface area of the appropriate pores.