Application of Macrocyclic Polymers for Metal Ions Separation

Chapter 58 Application of Macrocyclic Polymers for Metal Ions Separation... 

On the other way, to obtain higher selectivity and efficiency of metal ions removal in ion exchange processes those macrocycles are polimerized. In this way macrocycles obtained are more hydrophobic. They can be used as ion carriers for separation of metal ions from dilute aqueous solutions, especially in transport across plasticizer and liquid membranes [4]. For example, calixcrown oligomers used as ion carriers in the transport across liquid membranes exhibit the high selectivity for alkali metal cations. Also the application of crown ethers and calixarenes as the liquid membrane carriers is presented. The structures of monomers and polymers determines recognition and selectivity for metal ions. 

Other macrocyclic compounds such as cyclodextrins (CD) can be also polymerized and then used as ion carriers for transport of metal ions from aqueous solutions. The hydrophobic CD polymers have been used as ion carriers for separation of transition metal cations from dilute aqueous solutions by transport across polymer inclusion membranes. Recent developments of the CD polymers application in sorption processes of heavy metal ion from aqueous solution will be also presented in this chapter. It is also shown that hydrophilic, water soluble CD polymers obtained by cross-linking of CD with... 

Recent developments of the macrocyclic polymers application in ion exchange processes for separation metal ions from aqueous solutions will be also reviewed in this chapter. 

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