Preparation of a Cation Exchanger from Cork Waste: Thermodynamic Study of the Ion Exchange Processes
Preparation of a Cation Exchanger from Cork Waste：Thermodynamic Study of the Ion Exchange Processes

An ion exchanger was prepared by sulfonation of cork-waste chars. The exchange properties of the resultant material were characterized using Na+, Ca2+ or Fe3+ aqueous solutions. The content of metal ions in the solutions were determined by atomic absorption spectrometry. On the basis of the results obtained, the chemical equilibrium and its thermodynamic aspects related to the ion exchange process were studied. It was found that equilibrium constant K varies by the order: Na+0 and △5°>0, with -△G° following the sequence: Ca2+>Na+>Fe3+.