Zn-based MOF-chitosan-Fe3O4 nanocomposite as an effective nano-catalyst for azo dye degradation

Metal-organic frameworks (MOFs) have been fascinating catalysts for decolorization of azo pigments. A novel and easy approach to the preparation of a magnetic Zn2(BDC)2(DABCO) MOF has been reported as Fenton-like heterogeneous nano-catalyst for the degradation of azo dyes from aqueous samples. The samples were characterized by Fourier transform infrared spectroscopy (FTIR) for the evaluation of functional groups, X-ray diffraction (XRD) analysis for the investigation of crystal structure, nitrogen adsorption-desorption for the measurement of surface area, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) for the determination of size and morphology, energy-dispersive X-ray spectroscopy (EDX) to evaluate the chemical composition, and zeta potential for the investigation of surface charge. In this work, the MOF-chitosan-Fe3O4 nanocomposite (NC) was reported for azo dye degradation. To obtain high degradation efficiency, the effects of different parameters including nano-catalyst dose, temperature, contact time and oxidant volume on the decolorization efficiency were measured using experimental design approaches. Under optimized conditions, the degradation efficiency of methyl orange (MO) using MOF-chitosan-Fe3O4 nano-catalyst was obtained to be >99%. The results showed that the magnetic MOF could be used as a promising recyclable magnetic nano-catalyst for colored wastewater treatment.