Development and application of chitosan/poly(vinyl alcohol) films for removal and recovery of Pb(II)

Chitosan (CHT) and poly(vinyl alcohol) (PVA) films, with different mass ratios between CHT/PVA, were prepared to be applied as devices for removal of Pb(II). The characterization techniques showed that the addition of PVA decreases the crosslinking capacity among the amino groups from CHT, contributes to form a network with amorphous aspect, and changes the liquid uptake capacity of the films. On the other hand, PVA improved the mechanical performance of them. The capacity of removal of Pb(II), the kinetics parameters, and the isotherms models have a clear pH-dependent characteristic. The best results were found for the films with low or no amount of PVA at alkaline conditions. The recovery tests showed a recovery percentage above 50% of Pb(II) adsorbed onto all the CHT/PVA films samples. After the recovery tests, the morphological and mechanical aspects of the CHT/PVA films were preserved. The results show that the films developed in this work have excellent performance to be applied in the removal of Pb(II) from water.

► Chitosan/poly(vinyl alcohol) membranes were applied in the removal of Pb.
► The insertion of PVA improved the mechanical performance of membranes.
► The removal of Pb by the membranes has a clear pH-dependent characteristic.
► The recovery tests showed a percentage above 50% of Pb adsorbed onto the membranes.
► The membranes have excellent performance and can be applied in the water remediation.