Efficiency of fenton oxidation and membrane hybrid processes for paracetamol removal in seawater

Traces of Paracetamol (PCT) as a micropollutant in the environment, particularly in seawater (SW), have become a global concern in recent years due to the toxicity effect on humans and environment. Due to special characteristics, conventional wastewater treatment plants are able to degrade PCT partially. Therefore, an alternative treatment was necessary to treat PCT substance. Homogeneous Fenton oxidation is an efficient process to degrade PCT at various levels. Nevertheless, separation of dissolved iron by-products in the effluent caused a problem. Combination of Fenton oxidation and ultrafiltration treatment presents a promising opportunity as one of the alternative treatments for PCT removal across aqueous matrices and removal of iron residue. Despite promising, information related to combine Fenton and membrane process was lacking. Therefore, this study aims to evaluate the efficiency of the hybrid processes to remove PCT, represented in Chemical Oxygen Demand (COD), for both distilled water (DW) and seawater. In this study, crucial parameter Fenton's reagent with H2O2/Fe²⁺ ratio (w/w) was observed. In the DW matrix, optimal 1:0.5 ratio resulted 45% COD removal, whereas 1:1 ratio exhibited 37% COD removal in SW. Flat sheet Polyethersulfone (PES) with pore size of 30 nm and 7 nm (50 kDa) membrane was employed with a constant flux of 120 L/m^2·h. A lack of contribution of COD removal in DW and 37% in SW was observed during the ultrafiltration process, respectively. Furthermore, 54% and 92% removal of Fe²⁺ residue was observed during ultrafiltration at adjusted pH 8.5 in both water matrices using different membrane pore sizes, respectively.