Preparation, characterization, and application of chitosan-silver nanoparticles for Cu(II) and Zn(II) removal from oil refinery wastewater
Khilood S. Awad, Mariam Adnan Ibrahim
Abstract
Copper and zinc stand as one of the most alarming contaminants, presenting a formidable challenge in the realm of drinking water across numerous countries. To deal with this challenge, the sequestration of copper and zinc by adsorption has been extensively investigated in the solid media. Here, an adsorbent system based on a natural polymer - chitosan with physical cross-linking using silver nanoparticles is investigated for high binding, to get a new modified adsorbents (CS/AgNPs) that used these metal ions from simulated oil refinery wastewater. The adsorption mechanism is extensively studied via FTIR, zeta potential, dynamic light scattering (DLS), EDS, SEM, and BET. The prepared adsorbents (CS/AgNPs) have a bigger surface area than pristine chitosan that expanded from 4.74 to 36.34 m 2 /g, respectively. The prepared CS/AgNPs showed stronger adsorption ability than pristine chitosan attributable to its permeable structure and expanded surface area. In batch experiments, the Langmuir adsorption isotherms revealed that the highest uptake removal amount for Copper (II) and zinc (II) onto CS/AgNPs are 110.67 and 92.13 mg/g, correspondingly. These findings indicate that CS/AgNPs show a great potential as a proficient and selective materials for eliminating copper and zinc ions from aqueous solutions. • The prepared CS/AgNPs had increased surface area and separation ability of metal ions. • Solution pH and initial concentrations have a significant impact on Cu(II) and Zn(II) adsorption. • Adsorption mechanism was mainly electrostatic interaction for Cu(II) and Zn(II) ions. • The maximum adsorption capacities for Cu(II) and Zn(II) onto CS/AgNPs were 110.67 and 92.13 mg/g, respectively. • NH 2 and OH were the dominant reactive species in prepared CS/AgNPs composite.