Sustainable Removal of Basic Fuchsine and Methylene Blue Dyes Using Chicken Bone Biomass: Thermodynamics, Kinetics, and Insights from Experimental Studies and Decision Tree with Least Squares Boosting Predictive Modeling

Abstract

This study addresses the dual challenges of water pollution and waste management by exploring the valorization of chicken bone biomass in native (NBio) and calcined (CBio) forms as biosorbents for dye removal. Basic fuchsine (BF) and methylene blue (MB) were selected as model pollutants, and adsorption was assessed under varying operational conditions. Characterization using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) showed that calcination improved crystallinity, eliminated organic impurities, and increased surface area (247 m2/g for NBio vs. 370 m2/g for CBio). Adsorption tests revealed higher performance for CBio, with maximum adsorption capacities of 100 mg/g (BF) and 142.85 mg/g (MB) based on the Langmuir isotherm, while NBio with maximum adsorption capacities of 111 mg/g (BF) and 111.11 mg/g (MB) followed the Freundlich model. Adsorption kinetics indicated pseudo-second-order behavior, suggesting chemisorption. The possible interactions between dyes and the biosorbent are hydrogen bonding, electrostatic interactions, and Lewis acid–base interactions. Thermodynamic analysis highlighted exothermic behavior for NBio and endothermic, entropy-driven adsorption for CBio, with both processes being spontaneous. A decision tree with Least Squares Boosting (DT_LSBOOST) provided accurate predictions (R2 = 0.9999, RMSE < 0.003) by integrating key parameters. These findings promote chicken bone biomass as a cost-effective, sustainable biosorbent, offering promising potential in wastewater treatment and environmental remediation.