Synchronous Removal of Small-Sized Antibiotics by a Bifunctional Photocatalytic Nanofiltration Membrane in a Continuous Flow-Through Process under Multiple Influent Matrices

Abstract

Bifunctional photocatalytic nanofiltration (PNF) membranes are of increasing significance in removing micropollutants in the actual water environment, but there are still critical bottlenecks that greatly limit their practicality. In this work, a metal-free and visible light-responsive surface-anchored PNF membrane was fabricated for simultaneously and efficiently removing target antibiotics from real river water in a continuous flow-through process. The results exhibited that the optimal PNF-3 membrane was expectedly consisted of an inside tight sub-nanopore structured separation layer and an outside thinner, super hydrophilic mesoporous degradation layer. Consequently, the PNF-3 membrane irradiated via visible light exhibited outstanding removal rates of sulfamethoxazole, trimethoprim, and chloramphenicol (between 99.0 and 99.9%), accompanied with almost constant high water permeability. In addition, after repeating the fouling–physical rinsing process three times that lasted for 60 h, only sporadic adherent contaminants remained on the top surface, together with minimal total and irreversible fouling ratios (only 7.9 and 1.2%), strongly proving that the PNF-3 membrane displayed good self-cleaning performance. In addition, the acute and chronic biotoxicities of its permeate to Virbrio qinghaiensis sp. -67 were also reduced significantly to 11.4 and 10.1%, respectively. This study might provide valuable insights into the continuous enhancement of the practicality and effectiveness of PNF membranes in micro-polluted water purification scenarios.

Nanoarchitectonics Design Strategy of Metal–Organic Framework and Bio-Metal–Organic Framework Composites for Advanced Wastewater Treatment through Adsorption

“…Industries like textile, printing, chemicals, machinery manufacturing, leather, and pharmaceuticals contribute to water pollution . The by-products discharged from these sectors without proper treatment lead to the contamination of water bodies with heavy metals, dyes, antibiotics, pesticides, insecticides, and oil spilling. − Water purification has never been more crucial in light of these challenges. Conventional methods like chlorination, filtration, and coagulation-sedimentation have been the go-to solution and have been employed for ages to rid water of contaminants, yet they come with inherent limitations. − These techniques often rely on chemicals that can have adverse environmental impacts and may not effectively remove all contaminants.…”

Photocatalytic nanoparticles in flow-through annular photoreactors for continuous selenate reduction in industrial wastewater

“…12 Photocatalysis represents a promising and sustainable emerging water treatment technology that converts energy from light into electron-hole pairs that drive both oxidation and reduction reactions. 13,14 Photocatalysis can be applied towards many different applications, such as the treatment of organic pollutants [15][16][17][18] and green chemical/fuel synthesis, 19,20 and is enabled by a wide variety of semiconductor photocatalysts, with titanium dioxide (TiO 2 ) being the most widely and successfully used photocatalyst to-date. The photocatalytic reduction of Se(VI) and Se(IV) has been studied in some depth by various groups since its proof-of-concept in 1999, [21][22][23][24][25][26][27] and has been expanded to treat other recalcitrant Se compounds, such as SeCN.…”