COD Removal from Mixed Dye Wastewater Using Natural Pyrite Ore by Heterogeneous Fenton Process

Abstract

In this study, it was aimed to remove COD from wastewater prepared from a mixture of rhodamine 6G, methyl orange, and crystal violet dyes using natural pyrite ore as a heterogeneous fenton catalyst. The parameters of pH (2-9), H2O2 concentration (0.5-5 g/L), and catalyst dosage (0.5-5 g/L), which are thought to have major effects on the heterogeneous fenton process in COD removal, were investigated in a batch system. Characterization studies of natural pyrite ore were performed by X-Ray Diffractometer (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-Ray Spectroscopy (EDX), and Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy analyses. According to the data obtained, optimum values were determined as pH of 2, H2O2 concentration of 2 g/L, and 1.5 g/L of catalyst dosage. The COD removal efficiency was calculated as 94.7% under optimum conditions. According to the characterization results, it was determined that the pyrite ore contains (wt. %) Fe (44.87%) and S (51.02%) in a major proportion. The pyrite ore had a well crystalline and irregular structure. The fingerprint bands such as Fe-O, Fe-S are determined by FTIR spectrum. Pyrite was found as an effective catalyst for COD removal in this study and can be used as a promising catalyst in future heterogeneous fenton studies by expanding its catalyst property.