A High Flux Electrochemical Filtration System Based on Electrospun Carbon Nanofiber Membrane for Efficient Tetracycline Degradation

Abstract

In this work, an electrochemical filter using an electrospun carbon nanofiber membrane (ECNFM) anode fabricated by electrospinning, stabilization and carbonization was developed for the removal of antibiotic tetracycline (TC). ECNFM with 2.5 wt% terephthalic acid (PTA) carbonized at 1000 °C (ECNFM-2.5%-1000) exhibited higher tensile stress (0.75 MPa) and porosity (92.8%), more graphitic structures and lower electron transfer resistance (23.52 Ω). Under the optimal condition of applied voltage 2.0 V, pH 6.1, 0.1 mol L−1 Na2SO4, initial TC concentration 10 ppm and membrane flux 425 LMH, the TC removal efficiency of the electrochemical filter of ECNFM-2.5%-1000 reached 99.8%, and no obvious performance loss was observed after 8 h of continuous operation. The pseudo-first-order reaction rate constant in flow-through mode was 2.28 min−1, which was 10.53 times higher than that in batch mode. Meanwhile, the energy demand for 90% TC removal was only 0.017 kWh m−3. TC could be converted to intermediates with lower developmental toxicity and mutagenicity via the loss of functional groups (-CONH2, -CH3, -OH, -N(CH3)2) and ring opening reaction, which was mainly achieved by direct anodic oxidation. This study highlights the potential of ECNFM-based electrochemical filtration for efficient and economical drinking water purification.

Enhancing photocatalytic tetracycline degradation through the fabrication of high surface area CeO2 from a cerium–organic framework

“…The CeO 2 -300 exhibit a very high potential of +33 mV, which became more negative according to the increase of the calcination temperature. For CeO 2 -900, for example, the potential is −5.3 mV and −10 mV for the TC solution in the same pH (6). Considering these data and knowing that a positive zeta potential, as in the case of CeO 2 -300, is a reection of its positive residual charge on the surface of the material, which tends to attract a negative charge such as TC, we are able to explain the adsorption process as an electrostatic effect.…”

“…To date, various methods have been introduced to remove contamination by organic compounds, including filtration, 6 adsorption, 7 and photocatalysis. 8 Notably, the combination of adsorption and photocatalytic methods has proven a potential strategy to remove pollutants from wastewater without leading to secondary pollution.…”

Carbon nanomaterial-based membranes for water and wastewater treatment under electrochemical assistance

“…24,[217][218][219][220][221][222][223][224][225] During the electrochemically assisted processes, the molecules are captured and/or decomposed quickly when they migrate toward or pass through the nanocarbonaceous membranes, achieving high permselectivity. 219,[226][227][228][229] Moreover, the convection in the membrane pore efficiently improves the mass transfer to promote the electrochemical reactions. 230 The removal of dye molecules via electroconductive nanocarbonaceous membrane has been systematically investigated by both experiments and numerical simulations.…”