| The principal goal of this thesis work was to investigate cation exchange properties of highly charged swelling micas such as Na1Si 3AlMg3O10F2•xH2O (Na-2-mica), Na1.5Si2.5Al1.5Mg3O10F 2•xH2O (Na-3-mica), and Na2Si2Al 2Mg3O10F2•xH2O (Na-4-mica) and titanosilicates such as sodium Engelhard titanosilicate 4 (Na-ETS-4) and Na-titanosilicate. The three mica ion exchangers were synthesized using a NaCl melt method and the two Na titanosilicates were synthesized by hydrothermal treatment, and characterized by X-ray diffraction and scanning electron microscopy. In addition, 29Si and 27Al MASNMR spectroscopy was used to understand layer charge properties of Namicas and local chemical binding environment of Si and Al.;Cation exchange isotherms and Kielland plots of the above five ion exchangers were constructed in order to evaluate their selective cation exchange properties for Sr2+ and Ba2+ and heavy metals such as Hg 2+ and Co2+.2Na+&;Two different (001) phases of ~12 A and ~14 A were seen in the XRD patterns of the Na-micas after 2Na+&... |
