Facile redbrick clay as splendid catalyst for selective dehydration of alcohols

Abstract

Excellent catalytic activity of activated redbrick clay (ARB) for dehydration and highly selective conversion of cyclohexanol to cyclohexene and 1-phenylethanol to styrene is reported. The efficacy of the catalyst is compared with commercial catalysts, silica and α-Fe2O3, which performed poorly giving side products. Synergistic acidic properties and combinational Lewis and Bronsted acidic sites of ARB afforded superior performances relative to silica and α-Fe2O3 catalysts. Pyridine Fourier-transform-infrared spectra (FT-IR) and temperature-programmed desorption (NH3-TPD) measurements showed the presence of combinational Lewis and Bronsted acidic sites and a weak to mild acidic texture, which could facilitate favorable interaction between the ARB clay catalyst and the reactants (cyclohexanol and 1-phenylethanol). The physicochemical characteristics of ARB, commercial silica and α-Fe2O3 catalysts were investigated using X-ray diffraction, scanning electron microscopy, X-ray fluorescence, NH3-TPD, UV–visible diffuse reflectance spectroscopy, and pyridine FT-IR.