Novel hierarchical Co3O4/ZnO mixtures by dry nanodispersion and their catalytic application in the carbonylation of glycerol

Cobalt oxide nanoparticles (40-50 nm) were hierarchically dispersed on ZnO microparticles (0.2-1 mu m) using a low-energy dry mixing method, resulting in a zinc-cobalt interaction that stabilizes Co2+ sites. Raman spectroscopy is used to evidence the nature of the interphase reaction between ZnO and Co3O4 particles. The system evolves toward the formation of the spinel phase, ZnCo2O4, with further temperature thermal treatment at 400 degrees C. The catalytic activity of these materials was tested in the transformation of renewable materials via the carbonylation of glycerol by urea. Room-temperature-prepared CO3O4/ZnO systems exhibit catalytic behavior in the production of glycerol carbonate reaching conversions up to 69% in 4 h with close to 100% selectivity. (C) 2010 Elsevier Inc. All rights reserved.