Fe-Al-Pillared Clay Used for Conversion of Toluene Through Catalytic Wet Peroxide Oxidation

Abstract

In the present paper, the wet peroxide oxidation of toluene to benzaldehyde, which is great industrially important, is studied on solid catalyst. The catalyst (Fel  −Al) pillared bentonite (Fe−Al/B) is successfully prepared by cation exchanging of purified bentonite (B) with mixed hydroxyl-(Al-Fe) pillaring solution made from hydrolysis of corresponding metal salts with OH/M 3+ =2.5 (M=Al 3+ , Fe 3+), followed by calcination at 500°C to convert hydroxyl-Al and hydroxyl-Fe into intercalated polycations. Characterization studies are performed by use of chemical composition, XRD, SEM, TEM and analysis of N 2 adsorption/desorption. The basal spacing (d 001) and specific surface area of samples increased from 15.3 Å and 91.57cm 2 /g in the B to 19.4 Å and 229.75cm 2 /g in the Al−Fe/B. The Fe−Al/B clay catalyst has proved to be promising in toluene oxidation with H 2 O 2 , selectively forming benzaldehyde under the working conditions. The toluene conversion and the product distribution largely depended on the catalyst and oxidant concentrations and the nature of the solvent. Higher conversion of toluene and greater selectivity for benzaldehyde is obtained with acetinitrile solvent.