Graphitic Carbon Nitride (g-C3N4) based Photocatalytic membrane for enhanced Pharmaceutical Micropollutant Filtration and Degradation

Abstract

In the 21st century, the world is facing major challenges in water quality and global climate change due to an exponential growth in human population, so green technology is the need of the time to mitigate climate change and to minimize further factors that play a vital role in climate pollution. So, a combination of two technologies emerges as a new technology for the treatment of wastewater. Graphitic carbon nitride (GCN) has been integrated into polyacrylonitrile (PAN) membranes via an immersion- precipitation phase-transition reaction. This addition enhances the structural and morphological investigations, showing that GCN nanoparticles are evenly distributed in the PAN matrix. Different performance tests and characterization techniques confirmed that as the content of GCN increased, the performance of highly concentrated GCN-PAN hybrid enhances such as 0.25wt.% GCN-PAN membrane became more hydrophilic and less prone to fouling. More so, GCN-PAN membranes displayed the function of photocatalysis. Regarding photocatalytic activity, different loadings of hybrid membranes are used. Continuous degradation of metformin under sunlight irradiation was performed using 0.25wt.% GCN-PAN with a degradation rate of metformin of 50%. The presence of photogenerated h+ is high, and reactive oxidative species proved that these are the ones that were the cause of the observed degradation of organics and bacterial inactivation. This study proves that the addition of GCN into polymeric membranes enhances the performance, like permeate flux, salt rejection, and antifouling, due to the hydrophilic properties exhibited by GCN. Finally, the hybrid 0.25wt.% GCN-PAN membrane under the exposure of sunlight degrades wastewater treatment performance.