Imidazolium-Modified Silica Gel for Highly Selective Preconcentration of Ag(I) from the Nitric Acid Medium

Abstract

The ion-exchange behavior of an organomineral material with an imidazolium (1-methyl-3-(prop-2-yn-1-yl)-1H-imidazol-3-ium bromide)-modified silica gel was studied for the extraction of Ag(I) from nitric acid media. The extraction from multicomponent systems containing Fe(III), Co(II), Ni(II), Cu(II), Pb(II), and Mn(II) in 100- and 1000-fold molar excesses with respect to Ag(I) was shown to occur with high selectivity. Based on the data of X-ray diffraction and X-ray fluorescence spectroscopy for samples of modified silica gel, a mixed ion exchange–adsorption mechanism for the extraction of Ag(I) was proposed. The effect of the phase contact time and the concentration of nitric acid on the distribution coefficient of Ag(I) was studied. The selectivity factors of the extraction of Ag(I) from multicomponent systems containing foreign cations in 100- and 1000-fold molar excesses under steady-state and dynamic concentration conditions were calculated.

Synthesis and Characterization of Novel Thiosalicylate-based Solid-Supported Ionic Liquid for Removal of Pb(II) Ions from Aqueous Solution

“…It can be seen in the figure below where the lack of peak in the range of 3300–3500 cm −1 is significant. This indicates that the imidazolium cation is in interaction with the activated silica gel [ 27 ]. The presence of the expectable functional groups in the prepared materials at the respective position on the FTIR spectrum indicates the successful anchorage of the organic ligands and alkyl silanes onto the silica framework.…”