algerian journal of environmental science and technology
Volume 4, Numéro 2, Pages 771-776

Etude De L’adsorption Des Composés Phénoliques Sur Des Membranes Polymères à Base De Poly (vinyl Alcool) /β-cyclodextrine

Auteurs : Ghemati D. .

Résumé

The main objective of this work is the adsorption study of aromatic pollutants: 2-chlorophenol, 2-nitrophenol on membranes based on polyvinyl alcohol polymers modified with cyclodextrin. The polyvinyl alcohol-based membranes crosslinked with glutaraldehyde (PVA / GA) were prepared, then the incorporation of β-cyclodextrin in these membranes ((PVA / GA / β-CD) to different compositions (2, 4, 6, 8% β-CD) was realized. The synthesis was confirmed by infrared spectroscopic analysis (FTIR) and the behavior of the swelling of the membranes was studied by measuring the water retention. The equilibrium adsorption experiments of phenolic compounds: 2-chlorophenol, 2-nitrophenol, phenol, were carried out in aqueous solutions with an equilibrium time of 24 hours.The adsorption results of pollutants at different pH indicate that adsorption increases with increasing levels of β-CD in PVA membranes, and the maximum adsorption capacity is obtained at pH <pKa; The difference in adsorption capacity is due to the difference of the structure, the nature of the substituent and the pKa as well as the polarity Finally, the negative value of the free energy ΔGads indicates a physical adsorption, with possibility of regeneration of material, the adsorption isotherms indicate that the Freundlich model is more appropriate.

Mots clés

2-chlorophenol; 2-nitrophenol; Polyvinyl alcohol; Cyclodextrin ; Adsorption