Polyaniline/Reduced Graphene Oxide Doping Induced Abundant Active Sites in Enset Fiber as an Efficient Adsorbent Material for Wastewater Treatment

Abstract

Analysis of physicochemical properties and treatment of water is vital to the environment and living standard of society. In this study, polyaniline (PANI)/enset fiber (EF), reduced graphene oxide/EF, and PANI/rGO/EF composites as adsorbent material s were prepared via facile in situ chemical oxidative polymerization techniques. The as-synthesized materials were characterized using XRD, FTIR, UV-VIS, TGA, and FTIR spectroscopy. The physical characterization reveals the deposition of PANI and rGO on the surface of the EF confirmed by cloudy and wrinkled fibrous morphology from SEM image. After physical characterization, the adsorption performance of the proposed materials was tested using the batch method. A result shows maximum adsorption capacity (q_max) of Cu²⁺ and Pb²⁺ ions by PANI/rGO coated EF (EF) was 10.11 mg/g and 13.4 mg/g, respectively which is higher than pristine EF, PANI/EF, and rGO/EF. When all parameters were optimized, adsorptive removal efficiency of PANI/rGO/EF composite material towards Pb²⁺ and Cu²⁺ ions was 99% and 97.77%, respectively. The Freundlich isotherm data for Cu²⁺ and Pb²⁺ have a good fit with the experimental data (R² = 0.99 and 0.98), and Langmuir isotherm data for Cu²⁺ and Pb²⁺ (RL = 0.18 & 0.19), respectively. The pseudo-second-order kinetic isothermal was more fit with physiosorption at R² = 0.99 for Cu²⁺ and R² = 1 for Pb²⁺. Therefore, a synthesized novel material PANI/rGO/EF shows a remarkable adsorption performance compared with EF, PANI/EF, and rGO/EF due to doping-induced abundant active sites of composite material makes it a promising candidate for wastewater treatment techniques.