Complexation properties of water-soluble poly(vinyl alcohol) (PVA)-based acidic chelating polymers

Water-soluble polymers are attractive materials for pollutants removal thanks to their ability easily interact with soluble metal cations. In the present contribution, chemical modification of biocompatible and non-toxic poly(vinyl alcohol) (PVA) was achieved ethylene diamine tetraacetic acid (EDTA) groups, thus leading new water-soluble polymers, named PVA(EDTA). Modification carried out using Mitsunobu's reaction as an original pathway obtain statistical copolymers different EDTA functionalization rates in PVA chains. Preliminary study about variation rate chain length permitted determining optimal polymeric structures. Then, sorption properties heavy (i.e. Co(II), Ni(II), Zn(II), Pb(II), Cd(II), Cu(II)) on structures containing 15% chelating agent were determined by performing thorough adsorption isotherms or percentage, at a high low concentration, respectively. Additionally, performances tested more complex effluent constituted previous presence Ca(II) Mn(II) We demonstrated that PVA(EDTA) led great improvement comparison PVA. Indeed, results obtained showed capacities good selectivity towards some cations, consistency EDTA-metal formation constants. Isotherm Titration Calorimetry measurements allowed evidencing complexation stoichiometry, interaction constant enthalpy. This highlighted interest modifying basic commercial agents further applications based Polymer Enhanced Ultrafiltration (PEUF) process.