Heterogeneous Fenton-like Oxidation Of Oily Wastewater Using Green Synthesis Iron Nanoparticles Immobilized In Calcium Alginate Beads

With the rapid development of economy, water pollution has become an important factor to threat human health and economic development in China. Wastewater containing petroleum is one of the common wastewaters. Traditional Fenton oxidation is often used to treat hard-degradable organic pollutants including petroleum. To overcome the limitation of traditional Fenton oxidation, in recent years, Fenton-like oxidation based on iron nanoparticles (Fe NPs) has attracted attention widely due to its special function. However, since Fe NPs shows the agglomeration, oxidation and high cost, it still remain a challenges for Fe NPs used in wastewater treatment. In this study, the aim is to prepare Fe NPs as catalyst for Fenton oxidation of wastewater containing petroleum with low-cost, efficient and environmentally friendly. Therefore, (1) green synthesized Fe NPs entrapped by calcium alginate (CA-ELE-Fe NPs) were synthesized by eucalyptus leaves extract (ELE), which were used to treat wastewater. Scanning electron microscope (SEM), energy dispersive X-ray spectra (EDS) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the synthesis of CA-ELE-Fe NPs and CA-ELE-Fe NPs after reaction. (2) The influence factors such as dosage of CA-ELE-Fe NPs, H2O2, sodium dodecyl sulfate (SDS), initial pH value, initial concentration of petroleum and reaction temperature were investigated to understand the optimal conditions. (3) Comparison of CA-ELE-Fe NPs with ELE-Fe NPs and commercial Fe NPs was conducted to understand the oxidation catalytic function. Finally, the CA-ELE-Fe NPs was used to treat real wastewater. The results show that CA-ELE-Fe NPs was much better than that ELE-Fe NPs and nZVI, including catalytic performance and efficiency. The removal efficiency for simulate wastewater reached 80.24% while real wastewater is 71.74%.