Synergistic enhancement of chlorophenols removal using eco-friendly alginate@montmorillonite hybrid bio-capsules: insights from encapsulation and kinetic release studies

Abstract

This study investigates the synergistic effects of alginate@montmorillonite (Alg@Mt) hybrid microcapsules for enhancing water purification, focusing on improving the encapsulation of hydrophobic contaminants. Alg@Mt microcapsules were prepared through ionotropic gelation. Characterisation was performed using SEM-EDX, FTIR, XRD, and TGA. Encapsulation efficiency (EE), loading capacity (LC), and release behaviour were also examined. Alg@Mt microcapsules effectively removed phenol and its chlorinated derivatives from water. Incorporating Na-Mt improved structural and thermal properties, EE, and LC. Increasing the clay content to 60% (w/w) raised the EE of phenol and its more hydrophobic derivative, 2,4,6-trichlorophenol, from 39.74 ± 3.1% (w/w) and 63.91 ± 2% (w/w) to 60.56 ± 1.6% (w/w) and 82.28 ± 2.3% (w/w), respectively, with more controlled release rates, following Fickian diffusion mechanism. EE increased with phenolic substances hydrophobicity, while LC and release rates were inversely related. This approach is promising for removing hydrophobic contaminants from water.