Preparation, characterization and application of the nanocomposite PCL-PEG-PCL/Bentonite for the removal of methylene blue (MB) dye

This study focuses on the synthesis, characterization, and application of amphiphilic nanocomposite Poly ( ε -caprolactone)-Poly (ethylene glycol)—Poly ( ε -caprolactone) with Bentonite modified PCL-PEG-PCL/Bentonite (A2). The in situ copolymerization was carried out by ε-caprolactone and polyethylene glycol in presence of the intercalated Algerian Bentonite tetrabutylammonium hydrogen sulfate (TBHSA) (A1) to obtain a new amphiphilic nanocomposite PCL-PEG-PCL/Bentonite (A2). The nanocomposite was characterized by different techniques including Fourier transform infrared spectroscopy, X-ray diffraction, Transmission electron microscopy, Differential Scanning Calorimetryl and thermogravimetric analysis. The nanocomposite (A2) was applied as an efficient removal of methylene blue from aqueous solutions. The effects of the initial pH of a solution, contact time, and nanocomposite mass on the adsorption efficiency were investigated. Pseudo-first/second-order isotherms were applied to determine the efficiency of nanocomposite solid. The experimental data fitted well with the pseudo-second-order model for MB dye adsorption. The mass of nanocomposite increased, the adsorption capacity of dye increases to reach an optimal value at 0.13 g of adsorbent in pH = 6.8. The Langmuir isotherm exhibited the best fit, with an adsorption capacity equal to 600 mg/g.