Highly Selective Recovery of Phosphorus from Wastewater via Capacitive Deionization Enabled by Ferrocene-polyaniline-Functionalized Carbon Nanotube Electrodes

• DOI: 10.1021/acsami.2c06248
• Publication Date: 2022-07-08T17:30:48Z
• Authors: Fei Gao; Xuesong Li; Wei Shi; Zhiwei Wang
• Keywords: Capacitive Deionization

While capacitive deionization (CDI) is a promising technology for the recovery of nutrients from wastewater, selective phosphate wastewater containing high concentrations competing ions still huge challenge. Herein, we reported ferrocene-polyaniline-functionalized carbon nanotube (Fc-PANI/CNT) electrode prepared through amidation reaction and chemical oxidation polymerization, aiming highly phosphorus wastewater. The Fc-PANI/CNT with unique structure conductivity could efficiently adsorb complex synthetic nearly 100% selectivity, mainly because integration ferrocene an amide bond in Fc-PANI resulted enhanced charge transfer (Faradaic reactions) strong hydrogen bonding interaction its oxidized state. Density functional theory calculations showed that binding energies HPO42- H2PO4- were much greater than those other anions. affinity Fc-PANI/CNTs can be controlled electrochemically based on synergetic effects Faradaic reactions bonding, enabling charging/discharging cycles. adsorption capacity reached up to 35 mg PO43- g-1 NaCl/Na2SO4/NaNO3/NaH2PO4 mixture at 1.2 V, outperforming most CDI systems. also exhibited decent regeneration ability durability during repeated tests, demonstrating great potential application enrichment