Removal of Pb (II) from Aqueous Solution by Nano Organo-Composite Paramagnetic Particles: Study of Kinetic and Isotherm Models

The adsorption of lead on two adsorbents, montmorillonite clay (Mt) and magnetic nano organo-composite, was investigated in this study. The magnetic nano organo-composite has been developed by modifying montmorillonite clay with the organic surfactant Hexa decyltrimethylammonium bromide and adding magnetite nano-particles (MagMt-H). X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy were used to identify the nano organo-composite (MagMt-H). Two adsorbents were used to investigate the effect of lead initial concentration on its adsorption from aqueous solution. To comprehend the process of Pb adsorption, two adsorption isothermal models (Langmuir and Freundlich) and kinetic models (Pseudo-first order, pseudo-second order, Elovich, and intraparticle diffusion) were used. Surface adsorption in the nano organo-composite follows the isothermal models of Langmuir, as well as the pseudo-second order kinetic model, according to an examination of isothermal models and adsorption kinetics. The maximum adsorption capacity calculated from the Langmuir model at 30 °C in the nano organo -composite (73.58 mg g-1) was significantly greater than the value obtained in montmorillonite clay (49.54 mg g-1). The initial absorption rate (h) for nano organo-composite adsorbent (MagMt-H) with a value of 18.809 mg g-1min-1 compared to the montmorillonite (Mt) adsorbent with a value of 0.948 mg g-1min-1 indicates a much higher rate of lead (II) adsorption by nano organo-composite (MagMt-H). The results of this research demonstrated that the nano organo-composite (MagMt-H) was easily prepared and that new adsorption sites were created at its interface, making it extremely effective for removing lead from aqueous solutions.