2 research outputs found
Novel polymeric sorbents based on imprinted Hg(II)-diphenylcarbazone complexes for mercury removal from drinking water
This study describes the preparation of ion-imprinted polymers (IIPs) for the selective removal of Hg(II) ions from aqueous
media. Polymeric sorbents were prepared using different synthesis approaches to understand the influence of diphenylcarbazone
(DPC), used as non-polymerizable ligand, on absorption performance. In particular, bulk polymerization was first used to prepare
two polymers, IIP1 and IIP2, in the absence and presence of DPC. The trapping of the ligand in IIP2, demonstrated by Fourier
Transform Infrared Spectroscopy, promotes the formation of ternary complexes with mercury ions, and 4-vinylpyridine induces an
increase in binding performance, as indicated by the Kavalues (1.7 Ă 103±0.4 Mâ1 and 12.1 Ă 103±0.5 Mâ1, respectively) of
IIP1 and IIP2 high affinity binding sites. A third polymer (IIP3) was also synthesized using precipitation polymerization to evaluate the contribution of morphological characteristics on absorption performance compared with the addition of DPC.
Competitive studies revealed a stronger influence of IIP3 morphology on selectivity performance. Indeed, monodisperse
microbeads were obtained only in this case. Finally, the applicability of the polymers to real-world samples was demonstrated
through batch experiments using drinking water spiked with 1ÎŒgmlâ1 of Hg(II) ions, and the best removal efficiency of nearly 80% was obtained for IIP2