Author(s): Pinto, Ângela ; Moreira, Maria João ; Gonçalves, Afonso ; Rua, Ricardo F. ; Arruda, Luisa Mendes ; Gomes, Fernanda ; Antunes, Joana ; Bessa, João ; Cunha, Fernando ; Fangueiro, Raúl
Date: 2025
Persistent ID: https://hdl.handle.net/1822/97693
Origin: RepositóriUM - Universidade do Minho
Subject(s): 3D printing; gyroid structures; dye adsorption; textile wastewater
The textile industry is a major consumer of water, contributing significantly to global water pollution due to the discharge of untreated wastewater containing dyes and chemicals. Consequently, water contamination in this sector is a pressing issue that demands immediate attention. Hence, the present studies alternative filtration solutions using strategically designed gyroid structures for Plate and Frame filtration systems. These structures were produced via 3D printing following a stereolithography process using a resin based on urethane dimethacrylate. Samples were functionalized, via vacuum infusion, with active agents (zinc oxide nanoparticles or activated carbon), aiming at improving their filtration properties through the adsorption of contaminants. A solution based on an aliphatic polyurethane dispersion containing different concentrations of zinc oxide nanoparticles or activated carbon was applied to the gyroid structures. The resulting structures underwent characterisation tests to confirm the integration of the active agents and their adsorption capacity. Their morphological, mechanical, thermal, UV resistance and chemical resistance (pH=1, pH=3 and 1g/L Cl) properties were studied. Additionally, the gyroids ability to resist biofouling was assessed conducting standard protocols, using reference strains of Staphylococcus aureus and Escherichia coli to evaluate its bactericidal effectiveness. Initial antibacterial testing on zinc oxide nanoparticles demonstrated effective bactericidal capabilities against Staphylococcus aureus, with a minimum inhibitory concentration of 6.25 g/L. Additional results show a substantial increase in adsorption capacity of the functionalized gyroids following the inclusion of the active agents, namely zinc oxide nanoparticles, indicating potential for enhanced dye removal, specifically Remazol Yellow RR, Remazol Red RR Gran and Remazol Brilliant Blue BB Special. The results demonstrate that the incorporation of zinc oxide nanoparticles enhances adsorption and bactericidal properties of these structures, making them promising candidates for filtration systems of textile wastewater. Future developments focus on refining the functionalization process and assessing scalability for effective wastewater treatment.
