Nanostructured V-containing hydrotalcite-like materials obtained by non-stoichiometric anion exchange as precursors of catalysts for oxidative dehydrogenation of n-butane

Hydrotalcite precursors, and subsequently mixed oxide catalysts, with different loadings of vanadium were studied. A modified method of preparation at fixed pH but various amounts of the decavanadate anions below the stoichiometric value, was applied. Different vanadate species as well as carbonates were identified according to XRD patterns and FTIR spectra. The increasing content of vanadium resulted in change of the catalysts properties such as basicity (lower at high V loadings), pore size distribution (pronounced sintering for the highly loaded samples) and the catalytic activity. The highest specific activities were observed for the catalysts with high V content and decreased with decreasing transition metal loading, while the products distribution was more complex, depending both on the basicity and V content.