One-pot synthesis of microporous Fe2O3/g-C3N4 and its application for efficient removal of phosphate from sewage and polluted seawater

Abstract

The present work was performed to investigate the effective removal of phosphate from sewage and polluted seawater using microporous Fe2O3/g-C3N4 as the adsorbent. one pot synthesis The adsorbent achieved by direct heating of melamine in the presence of ferric oxalate which not only imposes the porous structure but also acts as a precursor for imbedded Fe2O3 nanoparticles. The removal efficiencies higher than 90% could be obtained in a wide pH range (3–10) and high ionic strength with short equilibrium time of 15 min Adsorption kinetics of phosphate was found to follow a pseudo-second-order kinetic model and adsorption process was well described by the Langmuir isotherm model with adsorption capacity calculated to be 52.5 mg PO43−/g adsorbent. The Fe2O3/g-C3N4 adsorbent could be regenerated easily by a mild alkaline solution treatment. Good adsorption performance, short equilibrium time and effective recyclability make Fe2O3/g-C3N4 a suitable alternative to the well-known adsorbents for removal of phosphate. The efficient removal of phosphate from sewage and polluted seawater in wide pH and ionic strength makes the proposed adsorbent promising for both the removal and recovery of phosphate from complex water and wastewater effluents.