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In this work, a polymeric adsorbent was synthesized by the imprinting technique for the measurement of Hg (II) ion from aqueous environmental samples. For this purpose, a novel aminothiol monomer has been initially synthesized then it has been used for complexing the mercury. The synthesized complex monomer copolymerized with methacrylic acid and ethylene glycol dimethacrylate and AIBN as the functional monomer, cross-linker and initiator respectively in the presence of a binary porogen of DMSO and toluene. The imprinted polymer was made after removing the mercury (II) ion by an acidic solution of thiourea. The results of batch procedures showed that the Hg (II)-imprinted polymer has adsorption capacity of 28 mg g-1and is high selective for adsorption of Hg (II) ion in competing with the other ions such as CH3Hg (I), Zn (II) and Cd (II) and also in comparing with non-imprinted polymers.

In this study, a handmade forcespinning device was developed to prepare polyacrylonitrile (PAN) and polyacrylonitrile-graphene oxide (PAN-GO) nanofibers. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to investigate the morphology and characterization of the nanofibers. Modified PAN-GO (0.2 %) nanofibers were obtained by reducing nitrile groups to amidoxime and then applied to uptake uranium ions from aqueous media. The maximum adsorption obtained for the adsorbent was 345.084 mg g -1 , which was obtained under optimal conditions of pH=5, contact time of 90 minutes and initial concentration of 25 mg L -1 . Also, the adsorption data were evaluated using Langmuir, Freundlich, Dubin and S-shaped isotherms. The results introduced the S-shaped isotherm model with a regression coefficient (R 2 ) of 0.999 as a suitable model. In addition, kinetic studies represented that uranium adsorption for less than 45 min fits well with the pseudo-second-order model (R 2 =0.979). At times longer than 45 min, the nanofibers follow the S-shaped kinetics (R 2 =0.999). Eventually, negative ΔG (Gibbs free energy change) represents spontaneous adsorption of uranium ions by PAN-GO (0.2 %) . The selectivity of PAN-GO nanofibers for the adsorption of competing ions was in accordance with the order Fe(II) < Ni(II) < CO(II) < U(VI) < V(V).