Iron-alumina synergy in the heterogeneous Fenton-type peroxidation of phenol solutions

C. DI LUCA; F. IVORRA; P. MASSA; R. FENOGLIO

CHEMICAL ENGINEERING JOURNAL

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2015 vol. 268 p. 280 - 289

1385-8947

Highly dispersed Fe2O3/Al2O3 catalysts (0.5-4 wt% Fe) were prepared by incipient wetness impregnation of iron citrate over a mesoporous alumina host. Their structural and textural properties were determined by N2 adsorption-desorption at 196 ºC, XRD, TEM, SEM?EDAX, Raman and XPS. The structure of the catalytic materials resulted similar to the g-Al2O3 support, exhibiting high dispersion levels of the iron oxide active phase with a narrow pore size distribution in the range of 2-7 nm and high surface areas. The capability of these systems as efficient and active Fenton-like catalysts, were further tested for the catalytic oxidation of concentrated phenol solutions (5 g/L) with H2O2 at 70 ºC in a batch reactor. The effects of iron concentration, catalyst concentration and the nature of the support were evaluated, under adjusted sub-stoichiometric oxidant concentration. Besides the positive impact of increasing the iron loading, a synergistic effect between Fe and Al species would be possibly responsible of the improvements observed using higher iron dispersions and/or support concentrations. The catalytic performance of these aluminabased catalysts resulted very promissory as they yielded: total phenol abatement, high mineralization levels (up to a maximum of 80%) and high oxidant consumption efficiencies (between 80% and 96%).