Effect of Pt on catalytic activity of Al- and Zr-pillared smectite

Abstract

This study aimed to investigate the physico-chemical properties of Pt dispersed in Al and Zr pillared saponite and montmorillonite. The chemical and morphological characteristics of prepared materials were carried out by using X-ray diffraction, scanning electron microscopy and Lewis to Brøensted acidity ratio (L/B) by pyridine adsorption followed by Fourier transform infrared analysis methods. The BET surface analysis results showed that the specific surface area of clays increased by Al and Zr pillarization and then reduced after Pt dispersion. Solid acidity and L/B as important features for the catalytic activity was increased significantly by modifications. The catalytic activity in citronellal conversion feasibility of the materials was examined systemically by evaluating the effects of pillarization and Pt dispersion on bifunctional catalytic activity of citronellal conversion by a tandem cyclization-hydrogenation conversion assisted by microwave irradiation. Bifunctionality of the catalysts in the catalytic testing was indicated from the total conversion parameter as well as selectivity to produce isopulegol and menthol from cyclization and cyclization-hydrogenation schemes. It is suggested that the presence of Pt in catalyst plays important role for hydrogenation step in producing menthol.