Heterogeneous Fenton oxidation of phenol in fixed-bed reactor using Fe nanoparticles embedded within ordered mesoporous carbons

Iron nanoparticles embedded within ordered mesoporous carbon catalyst (Fe-OMC) was prepared using a facile one-pot synthesis method. The as-synthesized catalyst was characterized by using FTIR, XRD, SEM-EDS mapping, HRTEM and XPS. The results revealed that Fe oxide nanoparticles were highly dispersed in the OMC. The prepared Fe-OMC materials as heterogeneous Fenton catalysts were specifically applied in the fixed-bed reactor which operated under continuous-flow condition, showing a promising performance in the oxidative degradation of phenol with high catalytic activity (e.g. phenol conversion nearly 100%) and stability. The effects of feed flow rate and catalyst bed height on the conversions of phenol and H2O2, the iron leaching concentration as well as pH values of reaction solutions were also systematically investigated to determine the optimal operation conditions. The experimental results showed that the Fe-OMC catalyst achieved the highest activity (>99% phenol and H2O2 conversion) with remarkable low iron leaching concentration (10-20 mg/L) under continuous-flow operations. The stability and reusability evaluations of Fe-OMC catalysts indicated the phenol conversion remains above 90% during a 39 h long-term evaluation. It can be finally concluded that the prepared Fe-OMC catalyst in this work shows promising potential to be an efficient heterogeneous Fenton catalyst for the degradation of hazardous phenolic aqueous solutions. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.