Removal of Bisphenol a from Aqueous Solution Using Cu-Ni Nanohybrid Synthesized from Cassia Siamea

Bisphenol A (BPA), a widely used industrial chemical, poses significant environmental and health risks due to its persistence and endocrine-disrupting properties. This study presents a green synthesis approach for copper-nickel (Cu-Ni) nanohybrids using Cassia siamea leaf extract, aimed at efficient BPA removal from aqueous solutions. The phytochemicals in Cassia siamea served as natural reducing and stabilizing agents, enabling eco-friendly nanohybrids without toxic reagents.
Characterization of the nanohybrids via FTIR, SEM, XRD, and UV-Vis spectroscopy confirmed their structural integrity and suitability for adsorption applications. Batch adsorption experiments were conducted to assess the influence of BPA concentration, contact time, pH, adsorbent dosage, and temperature. Optimal removal was achieved at 60 ppm BPA concentration, pH 6–7, 4 hours contact time, 0.04 g dosage, and 60°C temperature.
Adsorption isotherm modeling revealed that the Langmuir model best described the process, indicating monolayer adsorption on a homogeneous surface. Freundlich and Temkin models also provided insights into multilayer interactions and adsorption energetics. After adsorption analysis confirmed strong binding between BPA molecules and the nanohybrid surface.
The results demonstrate that Cassia siamea-derived Cu-Ni nanohybrids are a promising, sustainable, and cost-effective material for BPA remediation. This work contributes to the development of green nanotechnology for environmental purification and offers scalable solutions for water treatment in resource-limited regions.