Polymer inclusion membranes: The concept of fixed sites membrane revised

Evaluation of polymer inclusion membranes containing crown ethers for selective cesium separation from nuclear waste solution

“…The plateau in the transport rates (as shown by the constant P values beyond DTBB18C6 concentration of 10 mg/ml) can also be partly due to ligand aggregation which is a common phenomenon with the crown ether carriers [28]. This observation is in sharp contrast to those by Fontàs et al [29] who have explained the facilitated transport of metal ions on the basis of occurrence of liquid micro-domains where the carrier was solvated by the plasticizer, which at that stage acted as a solvating medium. Their suggestion of formation of the liquid micro-domains at higher carrier concentration in PIM though appears to enhance the facilitated transport with reagents such as Lasalocid A and Aliquat 336 as the carrier, which may in fact act in the opposite direction with crown ether carriers at higher ligand concentrations.…”

Transport of Phenol Through Inclusion Polymer Membrane (Pim) Using Copoly(eugenol-Dvb) as Membrane Carriers

“…PIM is made from a solution containing a carrier compound, plasticizer and polyvinyl chloride (PVC) as a matrix polymer that forms a thin, stable and flexible film. The existence of the matrix polymer membrane is expected to overcome the carrier leakage and the presence of plasticizer can stabilize the membrane system [5,[10][11][12]. Transport process of target compounds from source phase to stripping phase in PIM can be explained in three consecutive steps.…”

Structural effects on metal ion migration across polymer inclusion membranes: Dependence of transport profiles on nature of active plasticizer

“…In this concern, recently the hypothesis of coalescence of liquid-phase micro-domains inside PIMs was formulated to clarify the permeation mechanisms of Cd and Pt with two particular carriers, Lasalocid A and Aliquat 336, respectively [17]; however, to the best of our knowledge, no study of the variables that affect transport mechanisms in PIMs has been reported. Furthermore, although backscattering spectrometry, AFM [18], FTIR, X-ray, SEM, DSC, TGA [19][20][21], TIMM [22], Far-IR, Raman and Fluorescence correlation spectroscopy (FCS) [17] are some of the analytical techniques that have been applied for PIM characterization, the limited number of studies concerning correlations between characterization techniques and theoretical schemes from which it could be possible to explain the interactions between supporting polymer, plasticizer and carrier do not allow a systematic understanding of the role that the different PIM components play in membrane transport in order to facilitate the design of membrane systems for particular applications. With the aim to contribute in membrane performance optimization, in this work, we continue our studies on the characterization of metal ion transport across PIMs [21][22][23] through the evaluation of the dependence of indium(III) permeability with the nature of membrane plasticizer, using the commercial carrier CYANEX 272, and CTA as support.…”