Mixed cerium nanooxides as efficient and selective C-alkylation catalysts for gas phase methylation of phenol

Abstract

Phenol methylation is an acid-base catalysed reaction that produces valuable chemicals that are used in fine chemical synthesis. Methylation of phenol was studied over iron, vanadium and zirconium doped cerium nano oxides under optimized reaction conditions such as catalyst weight 0.5 g, phenol/methanol molar ratio 1/3 and WHSV 1.4 h−1 at 300 °C and 2 h. 80-90% conversion and 90% ortho selectivity are achieved with all prepared mixed oxides. o-cresol and 2,6-xylenol are the major products of the reaction. Catalytic activity depends on the number and strength of moderate and strong acidic sites on the surface which in turn depends on the nature and composition of the catalyst. Structural stability of the catalyst substantiates the heterogeneous nature of the catalyst.