Soybean oil‐based nanocomposites for dye adsorption: AESO‐chitosan‐graphene oxide synergy in water treatment

Abstract

This study presents the synthesis and characterization of a bio‐adsorbent (A‐C2‐G3) based on the acrylated epoxidized soybean oil (AESO) for the efficient removal of methylene blue (MB) dye from aqueous solutions. The adsorbent was synthesized by incorporating chitosan and nano graphene oxide into the AESO matrix, followed by crosslinking through the UV curing process. The effects of various parameters, including pH, contact time, initial dye concentration, adsorbent dosage, and ionic strength, on the adsorption performance were systematically investigated. The experimental data were best fitted by the Langmuir isotherm model, suggesting a monolayer adsorption process, with a maximum adsorption capacity of 263.87 mg g−1. The adsorption kinetics followed the pseudo‐second‐order model, indicating the significance of electron exchange between the adsorbate and adsorbent during the process. Three primary interaction mechanisms at the interface between MB and A‐C2‐G3 and the A‐C2‐G3 bio‐adsorbent were identified: electrostatic interactions, hydrogen bond formation, and π–π stacking. The reusability of the synthesized adsorbent was evaluated through a series of adsorption–desorption cycles, maintaining high adsorption capacities for up to three cycles. These findings highlight the potential of the AESO‐based bio‐adsorbent for effective MB dye removal from wastewater.