Zinc Adsorption Properties of Alginate-SBA-15 Nanocomposite

Abstract

Assessment of adsorption zinc (II) ions from aqueous solution using alginate-SBA-15 sorbent nanocomposite was investigated as a function of zinc concentration, solution pH, and contact time. For that purpose, the alginate-SBA-15 nanocomposite adsorbent was prepared through encapsulation method by immobilization mesoporous SBA-15 into a polymeric matrix. Identification of functional groups and surface morphology of the obtained nanocomposite was carried out by X-Ray diffraction (XRD), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR) and nitrogen porosimetry experiments. Sorption performance of the alginate-SBA-15 adsorbent during batch experiments was studied. A mathematically explanation of adsorption process using kinetics and isotherm models was also performed. Kinetic study was revealed that the pseudo second-order model has good agreement with the experimental results than the pseudo first-order model. Therefore, it indicates that the concentration of both alginate-SBA-15 and zinc metal ions are involved in the rate determining step of the sorption process. The qmax value for zinc (II) ions adsorption onto alginate-SBA-15 was found 46.3 mg g-1. According to thermodynamic analysis, physisorption and the endothermic of the sorption process nature of Zn(II) ions onto alginate-SBA-15 nanocomposite was revealed.