A series of ruthenium-based catalysts supported on acid-activated montmorillonite (PILC) and interspersed with titanium (Ru/Ti-PILCs) were prepared with various amounts of ruthenium. Their catalytic performances in the selective oxidation of cyclohexene, using tert-butylhydroperoxide (TBHP) as oxidant were checked. The clay structure modification by acid activation and impregnation of transition metals resulted in an enhanced Lewis and Bronsted acidities. The Ru/Ti-PILCs materials were characterized using X-ray diffraction (XRD), surface area and pore volume measurements, surface acidity followed by Fourier transform infrared (FTIR) spectroscopy, chemical analysis, and Scanning Electron Microscopy (SEM). It was found that all catalysts can selectively oxidize cyclohexene through allylic oxidation leading mainly to 2-cyclohexene-1-one (Enone) as the major product, and 2-cyclohexene-1-ol (Enol) as secondary product. With the 5 %Ru/Ti-PILC, it was possible to reach 59 % cyclohexene total conversion, and 87 % selectivity into 2-cyclohexene-1-one and 13 % selectivity into 2-cyclohexene-1-ol. external surface of the material is active, as large organic molecules cannot dodge in and out layers. Moreover, though non-polar molecules have reduced dimensions, they cannot penetrate into the material due to the hydrophilic character of the layers [3]. In order to obtain thermally stable materials with a greater interlayer distance, cations can be intercalated between the clay layers. These cations act as pillars that help in keeping the silicate layers separated, even in the absence of solvents.

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