Synthesis of OMS-2/NaY Zeolite hybrid materials as a catalyst for oxidation of phenol

Abstract

In this work, K-OMS compound was synthesized and then K was exchanged with Cu. In the second step Cu-OMS introduced to NaY zeolite and the synthesis zeolite/Cu-OMS hybrid materials were characterized by several techniques: Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Burner-Emmet-Taller (BET). The results showed that a new structure from zeolite and OMS was obtained. The catalytic activity of zeolite/Cu-OMS was investigated for oxidation of phenol to catechol and hydroquinone in present of hydrogen peroxide (H2O2) as oxidant in different solvents. The activity of phenol oxidation decreases in the series Cu-OMS-2/NaY>OMS-2/NaY at mild conditions. The effect of different factors such as amount of catalyst, temperature, type of oxidant and solvent was investigated. Finally, the kinetic of phenol oxidation with excess H2O2 over zeolite/M-OMS catalysts at several temperatures (40, 60 and 80 °C) was studied. These catalysts were very stable and could be reused for more than three times. The results showed a pseudo-first order kinetic with respect to phenol and the catalytic reaction occurred via a radical mechanism. Some advantages of this green catalyst are easy purification, environmental friendly, low catalyst loadings and non-toxic nature