Propanolysis of Methyl Paraoxon in the Presence of Aluminum-Titanate-Supported Erbium Oxide

Er2O3/Al2TiO5 and Al2TiO5 were evaluated as catalysts for the propanolysis of the organophosphate pesticide dimethyl 4-nitrophenyl phosphate (methyl paraoxon). The solid catalysts were characterized by energy-dispersive X-ray fluorescence (EDXRF), N2 physisorption (BET and BJH methods), and scanning and transmission electron microscopy (SEM and TEM). Physical–chemical characterizations revealed that the erbium content is 11.7% w/w in the novel solid and results in improved catalyst performance when compared with Al2TiO5, with textural properties favorable for methyl paraoxon diffusion in agglomerates composed of polydisperse spherical nanoparticles. Kinetic measurements at 80 °C show that the Er2O3/Al2TiO5 catalyst promotes a catalytic effect of at least 7 × 105-fold when compared with the first-order rate constant of the spontaneous propanolysis of methyl paraoxon.