The occurrence of potentially toxic elements (PTEs), such as Cu2+, Ni2+, Zn2+, Mn2+, Cd2+, and Cr6+, in water systems is closely linked to industrial activities and represents a significant environmental concern. Although some of these elements are essential at trace levels, their accumulation can lead to toxic effects and ecological imbalance. In this context, hybrid approaches combining adsorption and membrane separation have emerged as promising alternatives for water treatment. Chitosan-based materials are particularly attractive due to the presence of amino and hydroxyl groups, which enable both chemical modification and interactions with metal ions. In this study, chitosan hydrogel-membranes were prepared via solution casting and crosslinked with glutaraldehyde (G), epichlorohydrin (EP) and ethylenediaminetetraacetic acid (EDTA) at concentrations ranging from 5 to 25 mmol L?¹. The influence of crosslinking chemistry and concentration on network structure and adsorption behavior was investigated. FTIR, swelling, and gel fraction analyses confirmed the formation of stable three-dimensional networks. Thermal analysis indicated enhanced stability for glutaraldehyde- and epichlorohydrin-based membranes, while EDTA-crosslinked systems exhibited a distinct degradation profile. SEM images revealed dense morphologies, suggesting diffusion-controlled transport through the polymer matrix. Multicomponent adsorption tests (0.1 mmol L?¹, pH 4) showed higher affinity for Cr6+ and Cu2+ across all membranes. Based on these results, QG15 (15 mmol L?¹ of G), QEP15 (15 mmol L?¹ of EP) and QEDTA25 (25 mmol L?¹ of EDTA) were selected for further evaluation. Under single-component conditions (0.5 mmol L?¹), optimal performance was achieved at pH 3 and 1 g L?¹. QG15 showed higher removal of Cr6+ (85%, qe = 0.482 mmol g?¹), while QEDTA25 exhibited superior performance for Cu2+ (87%, qe = 0.431 mmol g?¹). These findings highlight the role of crosslinking chemistry in controlling adsorption selectivity, indicating that network design is a key factor for developing tailored chitosan-based membranes for water treatment.
Comissão Organizadora
Pedro Alves da Silva Autreto
Comissão Científica
Ferramenta completa de submissão, avaliação e publicação de anais para eventos científicos.
