Cadmium removal mechanisms from aqueous solution by using recycled lignocelluloses

Abstract

The three organic residuals of pistachio, peanut, and almond were investigated for the removal capacity and removal mechanism of cadmium ion from aqueous. Adsorption efficiency on reducing cadmium was evaluated with batch experiment parameters, contact time, sorbent dose, pH, and Cd2+ amount. The sorption process of metal ions was defined well with the pseudo-second order kinetic, and Langmuir isotherm model having an adsorption capacity (qemax) of 51.28 mg g−1 of pistachio, 62.11 mg g−1 of peanut, 78.74 mg g−1 of almond. The adsorbent was characterized by SEM, FTIR, and elemental analysis. The characterization study revealed that recycled lignocelluloses are composed of rough and porous surfaces with many active sites, contribute to metal ions removal in many ways, such as electrostatic interaction, ion exchange, complex formation, and physical adsorption. These findings highlighted that the shells can be effectively applied removal of divalent metal from aquatic solution.

Keywords

• Cadmium
• Recycled lignocelluloses
• Adsorption mechanisms
• Thermodynamic