Selectivity of Pb(II) transport across polymer inclusion membranes doped with imidazole azothiacrown ethers

The use of the steric effect of the carrier molecule in the polymer inclusion membranes for the separation of cobalt(II), nickel(II), copper(II), and zinc(II) ions

“…The intrinsic molar volumes of carries 2 and 3 are 169.5 mol/cm 3 (HLB = 4.87), while for carrier 1, it is 152.26 mol/cm 3 (HLB = 8.82). The roughness of investigated PIMs is comparable with that found for polymer membrane with derivative imidazole azothiacrown ethers prepared by Ulewicz et al 28 , which is equal from 3.3 to 5.3 nm. Also, small values of roughness (equal to 4.6 nm) showed polymer membranes with D2EHPA prepared by Salazar-Alvarez et al 34 .…”

“…A surface characterization study of the polymer membranes was performed by atomic force microscopy (AFM) according to the procedure described in paper 28 . The analysis of surface pore characteristics was made using the AFM image processing program NanoScope v.5.12, which enabled the calculation of two parameters, roughness (R q ) and porosity (ε).…”

Kinetics study of selective removal of lead(II) in an aqueous solution containing lead(II), copper(II) and cadmium(II) across bulk liquid membrane

“…Figure 6 shows that working with a high concentration factor will result in an even higher concentration of the ion of interest in the strip phase. In Table 3 the Permeability coefficient, P (lm/s), initial flux, J i (lmol/m 2 s), time of recovery (h) and recovery factor RF% for lead ion are compared with the corresponding values reported for the recovery of lead ions based on different carriers and different methods, so far reported in the literature [24,28,[31][32][33][34]. In terms of shorter time of recovery, higher J and P, and higher recovery percent, it is apparent that this work is sometimes superior and in some cases similar to the recovery of lead reported previously.…”

Studies on the separation of some transition metals using trialkylimidazole as selective extractant

“…Several extractants have been proposed for separation of Cu(II), Zn(II), and Cd(II) from aqueous solutions, e.g., carboxylic acids [10], derivatives of phosphinic acid [11], derivatives of acid amides, trioctylamine [11], alkylphenylamines [12], complex oximes [13], crown ethers [14][15][16] derivatives of ketones [17][18][19][20], derivatives of pyridine [21,22], as well as alkyl derivatives of imidazole [6,[23][24][25] and quaternary ammonium salt [26].…”