Selective removal of heavy metal ions using sol–gel immobilized and SPE-coated thiacrown ethers

Application of a Newly Synthesized Calixarene in Metal Ions Extraction

“…The relative selectivity coefficient (k9) data show that the immobilized ligands have greater selectivity toward Ag + over Hg 2+ as compared to the blank sorbent material. The selective complexation behavior between Ag + and Hg 2+ with ligands containing sulfur as donor atom such as in thiacrown ethers have been reported [42]. Similarly, although the selectivity coefficient is less than that reported by Saad et al, the improved selectivity toward Ag + over Hg 2+ observed in the experiment showed that the biphenyl structure provides a better binding sites to the metal ions probably via the oxygen atoms of the ether and the carboxylic functional groups.…”

“…It was observed that smaller diameters of sorbents exhibit greater percentage of extractions as they provide larger surface areas [42]. Therefore, 1 mm is adopted for the extraction study.…”

Preparation and characterization of silica gel/chitosan composite for the removal of Cu(II) and Pb(II)

“…Thus, the developments of functionalized mesoporous adsorbents for heavy metal ions using incorporated ligands with appropriate functional groups have generated considerable interest [8]. Sol-gel silica functionalized with different organic reagents such as crown ether [9], 1,5-diphenylcarbazide [10] and trialkyl phosphine oxides [11] have been prepared and applied for removal of metals. In addition, polyamine-functionalized materials have been also studied due to their implication in anion removal [12], CO 2 capture [13], in mobilization of biological molecules [14] and basic catalysis of fine chemistry reactions [15].…”

An experimental design to optimize the flow extraction parameters for the selective removal of Fe(III) and Al(III) in aqueous samples using salicylic acid grafted on Amberlite XAD-4 and final determination by GF-AAS

“…One way to selectively uptake metals of interest is obviously the use of chelating sorbents, and especially sorbents onto which specific ligands have been grafted or immobilized [20][21][22][23]. Using of such chelating sorbents may be interesting in analytical field too, as a separation support in solid-phase extraction (SPE) or in solid-phase microextraction (SPME).…”