Abstract:

This study investigated the enhancement of dye removal efficiency through a comparative analysis of carbon nanotube (CNT) and nano-clay (NC) incorporated in Pectin/Na-alginate bio-based hydrogel. The hydrogels were synthesized via gamma irradiation, with the incorporation of CNT and NC studied. Fourier transform infrared (FTIR) analysis confirmed successful hydrogel synthesis, revealing slight spectral changes upon the incorporation of CNT and NC into the hydrogel matrix. X-ray diffraction (XRD) analysis indicated the amorphous nature of the prepared nanocomposite hydrogels. Thermal properties, evaluated through thermogravimetric analysis (TGA), demonstrated the superior performance of CNT-incorporated hydrogels compared to NC-incorporated and unmodified hydrogels. Atomic force microscopy (AFM) revealed surface morphology changes with the incorporation of CNT and nanoclay. Additionally, the efficiency of dye removal, specifically for Malachite Green (MG) and Touliden Blue (TB) dyes, was evaluated. Results indicated the enhanced performance of CNT-incorporated hydrogels for MG dye removal, while nanoclay-incorporated hydrogels showed superior performance for TB dye removal. This study underscores the potential of CNT and NC incorporation in improving the dye removal capabilities of Pectin/Na-alginate bio-based hydrogels, offering valuable insights for environmental remediation applications. The Pseudo-second-order model emerges as the optimal kinetic model for both dyes on both hydrogels, indicating a chemisorption mechanism characterized by strong bonding. Isotherm studies further support these findings, with the Freundlich model demonstrating superior applicability in describing heterogeneous surface energies and multilayer adsorption processes observed in MG and TB dye adsorption. Thermodynamic analysis underscores CNTs@PC/Na-Alg/PAAc's preference for MG dye removal and NC@PC/Na-Alg/PAAc's effectiveness in TB dye removal. These results highlight the pivotal role of adsorbent material properties in shaping adsorption efficiency and mechanisms, crucial for optimizing dye removal processes in practical environmental remediation applications.