Camel Bone-Derived Hydroxyapatite as Green Adsorbent for Methylene Blue Dye

This study explores the feasibility of using camel bone-derived hydroxyapatite as a cost-effective adsorbent for removing methylene blue dye from aqueous solutions.The adsorbent was synthesized through calcination and characterized using BET, XRD, and TEM, confirming its crystalline structure and porous surface.Adsorption performance was evaluated under varying conditions, including contact time, adsorbent dosage, and dye concentration.The maximum adsorption capacity was found to be 23 mg/g, following the Langmuir isotherm model (R = 0.9894), confirming monolayer adsorption.Kinetic analysis indicated that the adsorption followed the pseudo-second-order model, with a rate constant of 0.0021 g/mgmin and an equilibrium adsorption capacity of 23.15 mg/g.Thermodynamic parameters revealed an endothermic process (H = 16614J/mol) driven by entropy gain (S = 64 J/molK) and spontaneous adsorption as reflected by negative G values (-9826 J/mol to -12066 J/mol in the temperature range of 303-363 K).The material maintained high efficiency across multiple reuse cycles, with 98% removal efficiency at an optimized temperature of 50C, highlighting its potential for sustainable wastewater treatment applications.