Heterogeneous Fenton oxidation of Orange II using iron nanoparticles supported on natural and functionalized fique fiber

A detailed study of a catalyst, synthesized by impregnation of iron species on the surface of functionalized fique fiber was performed. Wet impregnation ranging from 1 to 5 days was evaluated in order to assess the amount of iron deposited as a function of time. Quantification of adsorbed iron species was done by atomic absorption spectroscopy (AAS), getting values of 10.9, 14.9, 13.2, 15.9 and 14.9 wt% from 1 to 5 days respectively. X-ray spectroscopy (XRF), X-ray diffraction (XRD) and Fourier Transformed Infrared spectroscopy (FTIR) were used to determine the identity and quantity of species present in the sample, providing evidence of Fe2O3 (hematite) species and showing that under the impregnating conditions there is not complete evolution of iron crystalline structures. SEM images of the iron-impregnated functionalized-fiber revealed areas with substantial nanoparticles aggregation and areas where they are finely dispersed. This nanostructured biomaterial was tested as catalyst in the degradation and mineralization of Orange II (OII) under reaction conditions that promotes a Fenton heterogeneous type reaction. The best experimental conditions obtained under a Box-Behnken experimental design yield up to 93.23% OII degradation.