Polymeric membranes aminated, facilitated transport

In addition to the solution-diffusion mechanism, which is based only on physical interactions between the polymeric layer and the penetrant molecules, a reaction-based mechanism has been proposed when moieties with specific reactivity toward a target component are present within the membrane matrix, called the facilitated transport mechanism. High performances in terms of permeability and selectivity can be achieved in this case because the permeation of the target compound can count on a physical and chemical contribution, whereas all of the other penetrants diffuse through the matrix only because of the physical solution-diffusion contribution. An example of this mechanism is reported in Fig. 7.11 for the case of amine-based polymeric membranes in CO2 separation applications. 

Figure 7.11 Facilitated transport mechanism in amine-based polymeric membranes for CO2 separation applications.

Facilitated transport of CO2 through ion exchange membranes prepared by the plasma graft polymerization was investigated using amines as the carrier. The effects of various experimental factors, such as grafting level, substrates, monomers and carriers were investigated. 

Amide-containing dibenzo-16-crown-5 compounds, transport of metal perchlorates, 161-165 Amine(s) as carriers, carbon dioxide facilitated transport through functional membranes prepared by plasma graft polymerization, 252-268 Amine solutions, carbon dioxide facilitated transport through supported liquid membranes, 239-250 Amino acid derivatives, use as heavy metal ion carriers, 175-179... 

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