Novel polymeric sorbents based on imprinted Hg(II)-diphenylcarbazone complexes for mercury removal from drinking water

Abstract

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 K a values (1.7 × 10 3 ± 0.4 M − 1 and 12.1 × 10 3 ± 0.5 M − 1 , 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 1 μg ml − 1 of Hg(II) ions, and the best removal efficiency of nearly 80% was obtained for IIP2.

Molecularly Imprinted Polymers for Removal of Metal Ions: An Alternative Treatment Method

“…Mergola et al [22] published a study on mercury (II)-imprinted polymeric sorbents by different approaches using diphenylcarbazone as a chelating agent for mercury ions removal from solutions. The first and second mercury (II)-imprinted polymeric sorbents were prepared in the absence and presence of diphenylcarbazone, respectively; and the third mercury (II)-imprinted polymeric sorbent was also prepared to estimate the contribution of characteristic properties on adsorption capacity.…”

Urinary l‐kynurenine quantification and selective extraction through a molecularly imprinted solid‐phase extraction device

“…In this study, we attempted to develop a system that prevents time‐consuming pretreatments that require highly specialized operators. In particular, starting from the experience of our research group , molecular imprinting technology (MIT) was chosen to obtain a polymer selective for l ‐Kyn to be employed as a sorbent material in an SPE device to extract and purify endogenous l ‐Kyn before HPLC analysis. Thus, the matrix effect could be greatly reduced and the use of MS detector could be substituted with a less expensive and more accessible detection system such as a diode array detector (DAD).…”

Towards a new strategy of a chitosan‐based molecularly imprinted membrane for removal of 4‐nitrophenol in real water samples

“…The binding data were processed by Langmuir analyses to evaluate the binding characteristics of the prepared membrane. The Langmuir isotherm model assumes that the adsorption is in a monolayer; adsorption sites located on the surface of the adsorbent are uniform and they all have the same adsorbing ability . The adsorption of 4‐NO 2 Ph on 4‐NO 2 Ph‐chitosan imprinted membrane was fitted by a Langmuir model, given by Eqn .…”