Methylation of Aniline over Mn-Cu Ferrites Catalysts

Abstract

The structural and catalytic properties of the mixed spinel ferrite system Mn 1x Cu x Fe 2 O 4 (x=0, 0.25, 0.5,0.75, 1.0) have been investigated by X-Ray diffraction, Mössbauer and catalytic activity measurements. The variation of lattice parameter, crystallite size, and Mössbauer parameters of the product formed with the variation in the concentration of Cu has been studied. XRD Study revealed the formation of phase pure spinels with FCC cubic structure with particle size ranging from 5.21 nm to 20 nm. Lattice constant values showed constant decrease with increasing concentration. Mössbauer spectra showed the presence of Fe 3+ at both octahedral and tetrahedral sites. These ferrites were used as catalysts in the alkylation of Aniline. A maximum conversion of 80.5 % of aniline with selectivity of 98.6 % towards N-methylaniline (NMA) has been obtained at a temperature 673 K, Methanol : Aniline molar ratio of 5:1 and weight hour space velocity (WHSV) of 0.2 h-1. It was found that the yield is maximum for CuFe 2 O 4 . The result is supported by acidity measurements.