Catalytic oxidation of 2-(methylthio)-benzothiazole on alkaline earth titanates, ATiO3 (A= Ca, Sr, Ba)

DANIELA A. SALINAS ; CANDELARIA LEAL MARCHENA; LILIANA B. PIERELLA ; GINA PECCHI

MOLECULAR CATALYSIS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2017

2468-8231

The effect of the nature of the A-cation in alkaline earth titanates, ATiO3 (A= Ca, Sr, Ba), and thecalcination temperature (600 ◦C, 700 ◦C) on the catalytic performance for the oxidation of 2-(methylthio)-benzothiazole is reported. The solids were characterized by nitrogen adsorption isotherms, powderX-raydiffraction, O2 temperature-programmeddesorption,temperature-programmedreduction, Fouriertransform infrared spectroscopy, and diffuse reflectance spectroscopy/UV?vis techniques. A largerextent of the perovskite-type structure was obtained for the alkaline earth titanates at a calcinationtemperature of 700 ◦C. The increases in the catalytic oxidation with the ionic ratio of the A-cation(BaTiO3 > SrTiO3 > CaTiO3) was attributed to the well-defined perovskite structure with a lower extent ofsegregated phases. For the catalysts calcined at 700 ◦C, a larger conversion level (>75 mol%) and selectivitytowards the corresponding sulfone (>95 mol%) was achieved at a reaction temperature of 60 ◦C usingH2O2 (30%) as an oxidant. BaTiO3 calcined at 700 ◦C, provided the better catalytic performance and noactivity loss after four reuses, indicative of the largest stability in the reaction medium.