Molybdena-vanadia supported on alumina: Effective catalysts for the esterification reaction of acetic acid with n-butanol

The paper describes the preparation of alumina-supported molybdena-vanadia catalysts, their structural and textural characterization using XRD, N-2 adsorption, UV-vis and NH3-TPD techniques as well as their catalytic properties in the esterification reaction of acetic acid with n-butanol. The effects of esterification conditions including reaction time, catalyst loading and acid-to-alcohol mole ratio and of reactant pre-adsorption on the conversion were investigated. The catalytic activity correlated well with the number of strong acid sites which increased by increasing the vanadia content. In optimized conditions, conversions higher than 85% with 100% selectivity for n-butyl acetate can be obtained. Reactant pre-adsorption experiments suggested that the reaction follows the Langmuir-Hinshelwood mechanism. A good reusability of the catalysts after three reaction cycles was observed. A local interaction between molybdenum and vanadium on the catalyst surface has been evidenced. (C) 2013 Elsevier B.V. All rights reserved.