Degradation of 4-nitrophenol (4-np) using fe-loaded fly ash brick clay as a heterogeneous fenton catalyst

Abstract

Fly ash is one of the solid wastes generated from thermal power plants. Fly ash has certain catalytic capacity because of the possessions of porous structure. 4-Nitrophenol (4-NP) is considered to be toxic, non-biodegradable organics and it is recognized by Environmental Protection Agency as a priority pollutant. 4-NP was selected as model organic compound and fly ash making brick clay was used as raw material to prepare catalyst in this work. The catalyst consists of iron which is loaded on fly ash brick clay (FABC). The catalyst was prepared by impregnation method using fly ash clay support matrix. The prepared catalyst was used to study the performance of heterogeneous catalyst on degradation of 4-NP. The prepared catalyst was characterized by X-ray diffraction, scanning electron microscope coupled with energy dispersive X-ray, Fourier transform infrared spectroscopy. The influence of operating parameters such as the iron loading on matrix, dosage of H2O2, dosage of catalyst, initial concentration of 4-NP, initial pH and temperature was investigated on percentage degradation of 4-NP. The stability of prepared catalyst was also investigated by reusing the catalyst applying for four consecutive experiments. All the experiments were performed with 100 ppm of initial concentration. With operating condition of 10% Fe-FABC catalyst dosage of 2 g/L, pH 3.0, oxidant (H2O2) dosage 30 mM, reaction time of 40 min and room temperature, % degradation was more than 92% within these operating conditions.