Chitosan-Bentonite crosslinked film as indicator for copper (II) ions adsorption

Abstract

This paper reports on chitosan/bentonite crosslinked (ChB-ECH) film for removal of Cu (II). The effects of chitosan/bentonite ratio on the removal percentage were studied along with the effect of different Cu (II) concentration and the contact time on the film adsorption capacity, qt. The electrical properties of the film are studied, before and after the adsorption occurred, by using impedance spectroscopy for different parameters such as DC conductivity, the complex dielectric constants (ε’ and ε”) and complex electrical modulas (M’ and M’’). The results showed that the chitosan/bentonite ratio of 3:1 produces highest removal percentage at 29 %, while the contact time of 120 minutes was found to be optimum. An increment in the DC conductivity of the ChB-ECH film’s was observed up to 10-7 S/cm as the removal percentage of film increased. The film with the highest Cu (II) adsorb also showed the highest value for ε’ and ε” while exhibiting non-Derby behavior. Shifting of peak amplitude of the M” towards the higher frequency was also observed as the Cu (II) adsorption in the film increased. The results showed that all the electrical parameters can be utilized to determine the amount of adsorbed copper (II) in chitosan/bentonite film.

Comparative Studies of RSM, RSM–GA and ANFILS for Modeling and Optimization of Naphthalene Adsorption on Chitosan–CTAB–Sodium Bentonite Clay Matrix

“…Chitosan/bentonite Cross-linked Copper (II) ions % removal =29 [48] 18 Chitosan/bentonite Ionic exchange by intercalation Cadmium Ions…”

Sodium-Based Chitosan Polymer Embedded with Copper Selenide (CuSe) Flexible Film for High Electromagnetic Interference (EMI) Shielding Efficiency

“…Chitosan is a nonconducting polymer in its initial state with hydroxyl (-OH) and amino (-NH 2 ) groups available as binding sites for metal ions. Adsorption of metal ions into the binding sites of chitosan cause the resistivity of the polymer to decrease and overall conductivity to increase [23]. Works on chitosan for polymer electrolytes show an increase in conduction from 1.91 × 10 −4 µS/cm for pure chitosan to 2.41 × 10 −4 S/cm with the addition of 40 wt% of NaTf salt, and for works on a CS AgNO 3 system doped with 1 wt% alumina, the conduction increased to 2.3 × 10 −6 S/cm [24,25].…”