Enhanced adsorption of malachite green onto a composite material activated carbon and iron(III) oxide nanoparticles

isotherm, kinetic, and thermodynamic study

authored by: Magapgie N. Lincold, Mabou L. Jules, Ngassa P. Guy, Makota Suzanne, Mbouombouo B. Jacques, Tome Sylvain, Victor O. Shikuku, Gerard P. Tchieta
Abstract: In this study, activated carbon derived from black fruit kernels decorated with iron(III) oxide nanoparticles (AC@NPs) was prepared for effective adsorption of malachite green in batch mode. The adsorbents were characterized using FT-IR, XRD, SEM/EDX, TGA, and BET/BJH techniques. The effect of contact time, pH, initial concentration, and temperature was evaluated. Incorporation of NPs diminished the specific surface area by ~ 9.6%. However, this was accompanied by increase in equilibrium maximum adsorption capacity from 600 to 700 mg·g⁻¹ for AC and AC@NPs, respectively. The equilibrium data were best described by Hill’s isotherm and the pseudo-second-order (PSO) kinetic model. The PSO rate constants were indistinguishable implying the changes in surface chemistry, surface area, and porosity structures only affected equilibrium and not kinetics. Pore-diffusion was the sole rate-determining step for the upkate of MG onto AC@NPs. The adsorption of MG is inferred to be equilibrium-driven. The adsorption enthalpy of − 12 kJ·mol⁻¹ for AC and 52.602 kJ·mol⁻¹ for AC@NPs corresponding to the transition from exothermic physisorption to endothermic chemisorption denotes iron NPs introduced functional surfaces with increased binding energies. Impregnation with iron(III) oxide is shown to be an applicable strategy for tuning surface chemistry to increase adsorbent performance for MG removal from water.
Organisation(s): Institute of Mineralogy
External Organisation(s): University of Douala
Kaimosi Friends University College (KAFU)
Type: Article
Journal: BIOMASS CONVERSION AND BIOREFINERY
No. of pages: 20
ISSN: 2190-6815
Publication date: 13.11.2024
Publication status: E-pub ahead of print
Peer reviewed: Yes
ASJC Scopus subject areas: Renewable Energy, Sustainability and the Environment
Sustainable Development Goals: SDG 7 - Affordable and Clean Energy
Electronic version(s): https://doi.org/10.1007/s13399-024-06277-8 (Access: Closed)