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

Abstract

The main objectives of this study are to synthesize a new solid-supported ionic liquid (SSIL) that has a covalent bond between the solid support, i.e., activated silica gel, with thiosalicylate-based ionic liquid and to evaluate the performance of this new SSIL as an extractant, labelled as Si-TS-SSIL, and to remove Pb(II) ions from an aqueous solution. In this study, 1-methyl-3-(3-trimethoxysilylpropyl) imidazolium thiosalicylate ([MTMSPI][TS]) ionic liquid was synthesized and the formation of [MTMSPI][TS] was confirmed through structural analysis using NMR, FTIR, IC, TGA, and Karl Fischer Titration. The [MTMSPI][TS] ionic liquid was then chemically immobilized on activated silica gel to produce a new thiosalicylate-based solid-supported ionic liquid (Si-TS-SSIL). The formation of these covalent bonds on Si-TS-SSIL was confirmed by solid-state NMR analysis. Meanwhile, BET analysis was performed to study the surface area of the activated silica gel and the prepared Si-TS-SSIL (before and after washing with solvent) with the purpose to show that all physically immobilized [MTMSPI][TS] has been washed off from Si-TS-SSIL, leaving only chemically immobilized [MTMSPI][TS] on Si-TS-SSIL before proceeding with removal study. The removal study of Pb(II) ions from an aqueous solution was carried out using Si-TS-SSIL as an extractant, whereby the amount of Pb(II) ions removed was determined by AAS. In this removal study, the experiments were carried out at a fixed agitation speed (400 rpm) and fixed amount of Si-TS-SSIL (0.25 g), with different contact times ranging from 2 to 250 min at room temperature. The maximum removal capacity was found to be 8.37 mg/g. The kinetics study was well fitted with the pseudo-second order model. Meanwhile, for the isotherm study, the removal process of Pb(II) ions was well described by the Freundlich isotherm model, as this model exhibited a higher correlation coefficient (R2), i.e., 0.99, as compared to the Langmuir isotherm model.

Manganese Removal Using Functionalised Thiosalicylate-Based Ionic Liquid: Water Filtration System Application

“…The FTIR analysis of [HIMP][TS] ionic liquid showed absorption bands at 2958 cm −1 corresponding to -CH 2 stretching, 1628 cm −1 for C-N stretching, and a small peak protruded at 2232 cm −1 for the S-H group. This is in accordance with the synthesis of thiosalicylate ionic liquid from a previous study [17]. The O-H vibration in PVA-alginate-[HIMP][TS] decreased, indicating an interaction with the imidazolium cation.…”

Synthesis, physicochemical and antimicrobial properties of novel imidazolium based ionic liquids

“…The chemical compounds utilized in this study were supplied by Sigma Aldrich, SRL chemicals Scienti c, and Lichro Chemicals with a stated purity and are listed in S. Table 1. [35] was used for the preparation of this IL. An aqueous solution of sodium salicylate (0.05 mol in 50 mL deionized water) was added slowly to an aqueous solution of a Chloride-based IL (0.05 mol in 100 mL deionized water) in a 250 mL RBF.…”

Synthesis and characterization of novel solid-supported salicylate-based ionic liquid for adsorptive removal of Pb(ii) and Ni(ii) ions from aqueous solution

“…The higher the initial concentration, the higher removal capacities achieved by Si-Sal-SSIL in extracting Pb(II) ions from aqueous solution due to the vacant spaces available on the surface of adsorbent. 44 However, it can be seen that the removal percentages decreased with increasing initial concentration of metal ions solution due to the competition for adsorption sites among the metal ions. 11, showed that the removal efficiencies of Si-Sal-SSIL on the rst and second cycles decreased slightly by 1-2% for Pb(II) and Ni(II) ions.…”

“…Published by the Royal Society of Chemistry isotherm was developed for the homogeneous system, and it gives concept of monolayer adsorption of solute on the surface of sorbent. 44 Distribution of metal ions between liquid and solid surface was calculated by eqn ( 5) and (6). The important feature of Langmuir is commonly presented in terms of dimensionless separation factor, R L .…”