Photodegradation of Cyproheptadine using heterogeneous iron oxide–oxalate complex system under UV illumination

Abstract The development of high-performance advanced oxidation processes using UV irradiation energy has become a hot topic. A novel approach for the removal of organic compounds by an advanced oxidation process using an iron oxide catalyst and oxalate was proposed and investigated in this paper. Here, the removal of Cyproheptadine (CPH), a pharmaceutical compound, by a heterogeneous iron oxide–oxalate complex system with iron oxide Magnetite nanoparticles Fe3O4 (Fe2+/Fe3+ species) (MGN) was described and compared with heterogeneous photo-Fenton and homogeneous photo-Fenton processes. Thereafter, the influence of the basic operational parameters on the heterogeneous iron oxide–oxalate complex system was performed to enhance the process efficiency. The concentrations of formed H2O2 and formed Fe(II) ions during the process were determined over the range of conditions studied. It was found that the rate constant of CPH degradation by heterogeneous iron oxide–oxalate complex process is over 5.3-times and 13.5-times higher than that obtained by the heterogeneous photo-Fenton and the homogeneous photo-Fenton processes, respectively. The results show that the removal of CPH and the generation of each of H2O2 and Fe(II) depended strongly on the basic operational parameters on the heterogeneous iron oxide–oxalate complex system. The TOC measurements showed 80 % mineralization of a 10 mg L−1 solution of CPH after 180 min of treatment using heterogeneous iron oxide–oxalate complex process and over 99.5% of COD can be removed after 180 min of irradiation treatment. Increasing the solution pH rapidly decreased CPH rate constant. Conversely, CPH removal efficiency increased with increasing MGN concentrations up to 1.5 g L−1. The increase in the CPH concentration had a slightly negative effect on its degradation efficiency. The catalyst reusability study confirmed that MGN can be reused but not as reactive as the first use. The results have demonstrated the high performance of heterogeneous iron oxide–oxalate complex system using iron oxide Magnetite nanoparticles in organic contaminants degradation in industrial wastewater.