Multicomponent adsorption of heavy metals: competitive interaction and critical evaluation of reusability of magnetic activated carbon
Year: 2026
Type: article
Abstract: Magnetic activated carbons (MACs) derived from biomass have demonstrated considerable potential as a water treatment solution for the removal of heavy metals. In this study, sugarcane bagasse-derived MACs were produced by hydrothermal carbonization and subsequently thermochemically activated with KOH prior to application. Adsorption experiments were conducted using single- and multicomponent systems. The adsorption capacities were lower for the multicomponent systems due to interactions among heavy metals. Isotherm studies revealed first saturation of adsorption sites with Pb(II), while Cd(II) and Ni(II) continued adsorbing at higher concentrations, resulting in the adsorption capacities in order Ni(II) > Cd(II) > Pb(II). Kinetic studies demonstrated that the pseudo-first order and intraparticle diffusion–chemisorption models best described the adsorption behavior, indicating an adsorption process controlled by multiple mechanism. Equilibrium data were best represented by the Sips model, suggesting the simultaneous occurrence of single- and multilayer adsorption. Optimal adsorption capacities were achieved at pH 5.0 with 0.50 g L-1 and 30 min for equilibrium time (0.79, 1.06, and 1.45 mmol g-1 for Pb(II), Cd (II), and Ni(II), respectively). Thermodynamic parameters confirmed the spontaneous adsorption and exothermic nature for Pb(II) and endothermic for Cd(II) and Ni(II). The material was recycled for three cycles before it began to lose its magnetism. These results demonstrated the potential of magnetic activated carbon as an efficient and sustainable multifunctional adsorbent for heavy metal removal.
Source: RSC Advances
DOI: 10.1039/d6ra07517g
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,042
OpenAlex ID: W7165361338