Mesoporous CuO nanocatalysts for oxidative degradation of persistent organic pollutants

Abstract

A two-step strategy has been employed to synthesise three different mesoporous CuO nanocatalysts via a precursor mediated simple precipitation route. The CuO nanocatalysts are characterised by various analytical techniques and meticulously explored for oxidative degradation of two persistent organic water pollutants, viz., methyl orange (MO), and methylene blue (MB). The mesoporous CuO nanocatalysts exhibit varied activity for the degradation reactions depending on their synthesis parameters and textural properties. Reaction parameters such as the effects of catalyst dosage and reaction temperature are also addressed for degradation reactions. The results suggest that the increasing temperature led to higher reaction rates and activity. Moreover, the CuO synthesised from Cu(NO3)2·3H2O shows higher catalytic activity compared to those synthesised from CuCl2·2H2O and CuSO4·5H2O following the BET surface area trend. The study on kinetic/activation parameters reveals that degradations of persistent organic water pollutants over CuO nanocatalysts are endothermic in nature following pseudo first-order reaction kinetics. Further, CuO nanocatalysts provide a remarkable activity and stability with good recyclability up to five successive cycles of the degradation reactions.