3D-printed Zeolite–MgAl layered double oxides (3D-Ze/LDO) as a reusable adsorbent with dual functionality for effective anionic and cationic pollutant removal from water

Conventional powdered adsorbents often suffer from aggregation, difficult recovery, and poor reusability, limiting their practical application in wastewater treatment. In this study, a 3D-printed zeolite/MgAl layered double oxides (MgAl LDO) composite (3D-Ze/LDO) was successfully developed to overcome these challenges while offering dual-functional dye removal capabilities. Materials characterization, including scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy, confirmed the successful formation of zeolite - LDO composite in the 3D-printed structure. Adsorption experiments demonstrated that both 3D-Ze and 3D-Ze/LDO achieved high methylene blue (MB) removal at approximately 98 %, while the incorporation of LDO significantly enhanced congo red (CR) removal from 67 % (3D-Ze) to 79 % (3D-Ze/LDO) due to the introduction of anion-exchange sites. Kinetic studies revealed that PSO kinetics best described both MB and CR adsorption, indicating a chemisorption-dominated process. Additionally, 3D-Ze/LDO exhibited good reusability over four adsorption cycles, demonstrating its stability and potential for practical applications. These findings highlighted the advantages of 3D-printed adsorbents in addressing the limitations of powdered materials while leveraging the dual-functionality of zeolite and LDO for efficient cationic and anionic dye removal.