Synthesis and Characterization of Titanium Supported on High Order Nanoporous Silica and Application for Direct Oxidation of Benzene to Phenol

Alireza Badiei,Javad Gholami,Yeganeh Khaniani

doi:10.1155/2009/292483

Abstract

Direct oxidation of benzene to phenol in liquid phase by H2O2peroxide was examined over Ti/ LUS-1 catalyst in methanol and acetic acid as solvents. The maximum yield and selectivity of the phenol produced was obtained in the presence of acetic acid. It can be attributed to the stabilization of H2O2as peroxy acetic acid species in the radical mechanism for this reaction. Acetic acid interacts with hydrogen peroxide over Ti/LUS-1 and produces acetoxy radicals.

Highlights

Nanoporous materials nowadays cover a broad range of economically very important processes related to the upgrading of crude oil and natural gas as well as the profitable production of fine chemicals[1]
The materials possess remarkable catalytic activity in selective oxidation of organic compounds. Microporous titanium silicates such as zeolites Ti-silicalite-1 and Ti-Beta are extremely efficient catalysts for epoxidation of alkenes in the presence of aqueous H2O2 and tert-butyl hydroperoxide as oxidants, which is attributed to the unique architecture of titanium centres that are isolated in the silicate framework[3].The dimensions of micropores within zeolitic structures limit the application of these catalysts to catalytic reactions with small molecules
The (100) diffraction peak indicates welldefined mesostructure solid supports and the XRD patterns show that the loading of TiO2 on LUS-1 in solution do not affect the ordered of mesostructure

Summary

Introduction

Nanoporous materials nowadays cover a broad range of economically very important processes related to the upgrading of crude oil and natural gas as well as the profitable production of fine chemicals[1]. Hydroxylation of benzene to phenol with hydrogen peroxide has been carried out using titanium supported on LUS-1 nanoporous silica. In the first step of the study, titanium catalysts containing TiO2 species on high surface area supports of LUS-1 were synthesis and characterized and in second step using of for direct oxidation of benzene to phenol with hydrogen peroxide in the liquid phase.

Results

Conclusion