Mild oxidation of tetrahydrothiophene to sulfolane over V-, Mo- and W-containing layered double hydroxides Original Research Article

A series of layered double hydroxides (LDH) with Mg2+ and Al3+ cations in the brucite-like layer and W-, V- and Mo-oxospecies in the interlayer gallery were prepared, characterized and tested as catalysts for the sulfolane synthesis by mild sulfoxidation of tetrahydrothiophene (THT) with H2O2. The structural and textural properties of solids and the nature of the metal species were investigated by X-ray diffraction (XRD), N2 adsorption, thermogravimetric analysis (TGA), diffuse reflectance ultraviolet spectroscopy (DRUV), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The catalytic activity was evaluated in the liquid-phase THT oxidation with dilute H2O2 in various organic solvents and temperature range of 20–30 °C. The best performances in terms of catalytic activity and stability were obtained with WO42−-containing LDH catalyst.