Carbon electrochemical membrane functionalized with flower cluster-like FeOOH catalyst for organic pollutants decontamination.

Decorating active catalysts on the reactive electrochemical membrane (REM) is an effective way to further improve its decontamination performance. In this work, a novel carbon electrochemical membrane (FCM-30) was prepared through coating FeOOH nano catalyst on a low-cost coal-based carbon membrane (CM) through facile and green electrochemical deposition. Structural characterizations demonstrated that the FeOOH catalyst was successfully coated on CM, and it grew into a flower cluster-like morphology with abundant active sites when the deposition time was 30 min. The nano FeOOH flower clusters can obviously boost the hydrophilicity and electrochemical performance of FCM-30, which enhance its permeability and bisphenol A (BPA) removal efficiency during the electrochemical treatment. Effects of applied voltages, flow rates, electrolyte concentrations and water matrixes on BPA removal efficiency were investigated systematically. Under the operation condition of 2.0 V applied voltage and 2.0 mL·min-1 flow rate, FCM-30 can achieve the high removal efficiency of 93.24% and 82.71% for BPA and chemical oxygen demand (COD) (71.01% and 54.89% for CM), respectively, with only a low energy consumption (EC) of 0.41 kWh·kgCOD-1, which can be ascribed to the enhancement on OH yield and direct oxidation ability by the FeOOH catalyst. Moreover, this treatment system also exhibits good reusability and can be adopted on different water background as well as different pollutants.

High performance polypyrrole coated carbon-based electrocatalytic membrane for organic contaminants removal from aqueous solution.

Electrocatalytic filtration process adopting the electrocatalytic membrane as both filtration membrane and active electrode showed great prospect on the organic pollutant removal from water. In this work, a high-performance metal-free polypyrrole (PPy) coated carbon-based electrocatalytic membrane (PPy@CCM) was developed through the facile and controllable electro-polymerization deposition method. Structural properties and electrochemical performance of the prepared PPy@CCM were characterized systematically. The influences of preparation parameters and operational parameters on water treatment performance of PPy@CCM were also investigated. Results indicates that the spherical PPy particles uniformly distributed on the surface of PPy@CCM. Coating with PPy particles can significantly improve the hydrophilicity and electrochemical activity of CCM, therefore PPy@CCM has lower hydraulic resistance and higher water treatment performance than CCM. The phenol and chemical oxygen demand (COD) removal rates obtained by PPy@CCM are up to 99.51% and 89.90%, respectively, under the optimal condition of 2.0 V cell potential, 2.50 g·L-1 Na2SO4, 1.5 ml·min-1 flow rate and 50 mg·L-1 phenol, and only 0.5 kWh·kgCOD-1 energy consumption is consumed. In addition, PPy@CCM also exhibits good treatment performance in different water matrixes. Moreover, PPy@CCM has good stability for several cycle operation and considerable applicability for different types of organic pollutants removal. The oxidation mechanism study reveals that PPy@CCM has both direct and indirect oxidation activity during the electrocatalytic filtration treatment, and the coating of PPy can improve the direct oxidation ability and ·OH yield of CCM.

Preparation and application of high-performance and acid-tolerant TiO2/carbon electrocatalytic membrane for organic wastewater treatment.

Acidic organic wastewater with toxic and carcinogenic properties has long been a tough problem for industrial treatment. To break down the barrier of poor acidic stability as well as the high cost of materials and reactors, a novel strategy of utilizing a high-performance and acid-tolerant TiO2/carbon electrocatalytic membrane (TiO2/CEM) for acidic organic wastewater treatment was proposed. Study results showed that high concentrations of organic pollutants were separated and degraded by the synergistic effects of membrane separation and electrocatalytic oxidation simultaneously on the TiO2/CEM. The great treatment performance with membrane removal efficiency of >97.4% was obtained by treating acidic rhodamine B (RhB) dye wastewater under optimized applied voltage. Treatment experiments under various pH and electrochemical tests demonstrated the outstanding acid-tolerant property and long service life of TiO2/CEM. Furthermore, the feasibility of TiO2/CEM for industrial application and various acidic organic wastewater treatment was proved by treating typical organic pollutants (phenol, tetracycline and oil) under high acidic circumstances.