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Transport of mercury through liquid membranes containing calixarene carriers

“…[34]. Although a number of carriers for the transport of alkali and alkaline metal ions using BLMs have been used so far [34][35][36][37], relatively few carriers have been reported for the selective and efficient transport of heavy metal or mercury ions [13][14][15][16][17][18][19][20][38][39][40].…”

“…It was found that calyx(4)arene derivatives [6,12,13,[19][20][21] have the desired ability of selective extraction of Hg 2+ ions. These results initiated investigation of the transport of Hg 2+ by calixarene derivatives as a carrier through bulk liquid membrane and the influence of the temperature, stirring effect, carrier concentration and the type of solvent on the transport process.…”

“…The development of new methods for the selective removal of mercury is an important objective for environmental remediation. For this reason, a variety of calyx(4)arene derivatives were prepared for selective removal of Hg(II) ions from waste effluents [19][20][21]. Calix(n)arenes have been made in the design and synthesis of artificial receptors for cations, anions, and neutral organic molecules [22][23][24][25][26][27][28][29][30][31].…”

Anion Receptors Based on Calixarenes

“…Similarly, preliminary studies showed that 55 can be efficiently used as an extractant for the selective extraction of Cr 2 O 7 2-from aqueous solution to the organic phase (CH 2 Cl 2 ). Some of these calixarenes were anchored [73] to a polymer support using bromoethylated polystyrene and used for dichromate extraction at low pH values (pH=1.5). Similar types of compounds 56a,b were shown [74] to bind a variety of anionic guest species (halides, HSO 4 -, H 2 PO 4 -) in DMSO-d 6 , some of them with surprisingly high complexation constants (H 2 PO 4 -, K 56a =4.5·10 4 M -1 ).…”

Selective Ion Transport and Complexation in Layer-by-Layer Assemblies ofp-Sulfonato- calix[n]arenes and Cationic Polyelectrolytes

“…Because of their basket shape they are suited for the complexation of small molecules and ions. Applications as extractors of metal ions, [22,23] as carriers in liquid membranes, [24,25] and as sensors for heavy-metal ions [26] and volatile organic components (VOCs) were described. [27] Although there is a growing interest in ultrathin, defect-free membranes exhibiting high flux and high separation capability, until now only a few attempts have been made to incorporate calixarene derivatives in membranes to improve their separation capability.…”