Abstract
In this study, beads of chitosan (CS) containing polyvinyl alcohol (PVA) were prepared and cross-linked with tetraethoxysilane (TEOS). The cross-linking of CS/PVA beads with TEOS preserved the active adsorption sites of CS and also enhanced its chemical and mechanical stability. The chemical solubility test and swelling behavior of the beads were studied, especially, in acidic media. Adsorbents were characterized by infrared spectroscopy and scanning electron microscopy. The removal of Cu2+ ions from aqueous solution on the prepared beads was investigated in a batch adsorption system as a function of pH, amount of adsorbent, initial concentration of metal ions, and contact time. The adsorption data were analyzed on the basis of Lagergren pseudo-first-order, pseudo-second-order and interparticle diffusion models. Experimental data were fitted with Langmuir and Freundlich isotherm models. The maximum adsorption capacity of cross-linked CS/PVA/TEOS beads for copper ions was of 224.6 mg/g according to Langmuir isotherm for Cu2+ ions. The calculated thermodynamic parameters (∆G°, ∆H° and ∆S°) indicated a spontaneous and endothermic adsorption reaction.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
