Fabrication of recyclable magnetic biosorbent from eggshell membrane for efficient adsorption of dye

Magnetic eggshell membrane powder (MESM-P) were synthesized and used to remove Congo red (CR) dye from wastewater. The biosorption performance were evaluated at varying operating conditions, including initial pH, dye concentrations, contact time, and temperatures. Thekinetics studies revealed that the adsorption process can be better described by the pseudo-second-order model. The adsorption process conformed better to the Langmuir model with a maximum biosorption capacity of 1037.02 mg g⁻¹ _. An ethanol–water system was employed as a fast, effective and harmless desorptionsolvent for the regeneration of biosorbent. The system of 70% ethanol-30%water atpH 13 presented the maximum desorption efficiency up to 96.16%. The MESM-P could be easily regenerated and remained a high adsorption efficiency of 79.55% after ten reusing cycles. Therefore, the prepared MESM-P biosorbent could be a promising candidate for the removal of dye pollution from wastewater.