Potential degradation of hazardous dye Congo red by nano-metallic particles synthesized from the automobile shredder residue

Abstract

This study was carried out on the degradation of Congo red (CR) in an aqueous solution by nano-metallic particles (NMPs). The NMPs were synthesized from the leachate of automobile shredder residue. Scanning electron microscopy was performed to analyze the morphology of particles. Fourier transform infrared spectroscopy (FTIR) was also done to demonstrate the possibility and changes of various functional groups before and after the reaction of NMPs. The effect of the dosages of NMPs, pH values of solution, concentrations of CR and H2O2 on CR degradation was studied. The results of the present study confirm that the CR degradation rate was improved by increasing the dosages of NMPs and H2O2 up to certain limit and then reduced gradually. However, degradation rate was reduced by raising the pH values and concentration of CR. The pseudo-second-order kinetics was found to be suitable for the degradation of CR by NMPs under Fenton-like process.