Chicken feather-derived carbon electrodes for capacitive deionization using poly(vinyl alcohol)-glutaraldehyde as the binder

Abstract

Capacitive deionization (CDI) is an emerging technology which is being developed as a promising desalination alternative for charged species from salt water, being electrode materials as key drivers for highly efficient process. Here, we describe synthesis of highly porous activated carbons from chicken feathers using pyrolysis followed by chemical activation with potassium hydroxide in a 1:4 ratio to produce sustainable, scalable, and sustainable carbon electrodes for CDI. Poly (vinyl alcohol) (PVA) was used as binder to modify chicken feather activated carbons (CF-AC), which were subsequently crosslinked with glutaraldehyde (GA) to produce CF-AC-PVA-GA polymers through acetylation reaction. This resulted from improving hydrophilicity of CF-AC-PVA-GA polymers to raise the electrodes' resistance. Prepared materials were characterized using scanning electron microscopy, Fourier transform infrared, X-ray diffraction, Brunauer-Emmett-Teller and cyclic voltammetry. Fabricated CDI electrodes were used to investigate their performance for desalination, and exhibited different electrosorption capacity at different applied potentials. Modified electrodes possessed good stability in shear conditions and CDI process was stable and reproducible around 16 electrosorption cycles. Salt removal capacity of the modified electrodes (CF-AC-PVA-GA) was found to be 3.89 mg g−1. The obtained outcomes offer important considerations of ions electrosorption and help advancing CDI system for water treatment and desalination. HIGHLIGHTS Activated carbons (ACs) were prepared from chicken feathers via pyrolysis using KOH.; Poly (vinyl alcohol) and glutaraldehyde were used for modification of ACs.; Modified carbon materials were used for capacitive deionization (CDI) electrodes.; The CDI electrodes retained good stability around 16 electrosorption cycles.; Salt removal capacity of the fabricated CDI electrodes was found to be 3.89 mg g−1.;

Keywords

• activated carbon electrodes
• capacitive deionization
• desalination
• electrosorption
• waste chicken feathers