Cs salt of Co substituted lacunary phosphotungstate supported K10 montmorillonite showing binary catalytic activity

Abstract

The present study explores the fabrication of cesium salt of cobalt substituted lacunary phosphotungstate supported 1(10 montmorillonite. Lacuna creation in the phosphotungstic acid and cobalt substitution was confirmed from FT-IR spectroscopy. The presence of cobalt in its +2 oxidation state was established from UV-Vis DRS and XPS study. The high acidity of the catalyst was evidenced from NH3-TPD measurement. Other characterization techniques like XRD, N-2 adsorption-desorption, TG-DTA and H-2-TPR discovered various dimensions relating to the catalyst. This single system, enriched with high acidity and oxidative ability showed superlative catalytic activity in the absence of any solvents towards both esterification of oleic acid with methanol and selective oxidation of benzyl alcohol to benzaldehyde. While giving 94% methyl oleate yield in the esterification reaction, it showed appreciable results toward the oxidation reaction with 91% conversion and 99% benzaldehyde selectivity in just 2 h. (C) 2012 Elsevier B.V. All rights reserved.