Preparation of MgAl LDH intercalated by α-PW12O403- for adsorptive removal of direct violet dye from aqueous solution

The preparation of polyoxometalate-intercalated MgAl layered double hydroxides (LDH) has been conducted and employed as an adsorbent for direct violet dye removal from aqueous solution. The MgAl LDH was firstly prepared by coprecipitation method under basic condition then followed by an ion-exchange process with K3[α-PW12O40].nH2O solution. The obtained materials were characterized by XRD and TG-DTA. Related to the X-ray diffraction pattern, the synthesized MgAl LDH exhibited typical diffraction peak at 2theta of 11.56° correspond to the basal distance of 7.72 A. While after intercalated by [α-PW12O40]3-, the typical diffraction peak of MgAl LDH shifted to the lower diffraction angle of 8.88° that corresponds to the basal spacing of 9.95 A. The utilization of the prepared materials as an adsorbent for direct violet dye removal from aqueous solution showed that the intercalated LDH exhibited better adsorption capacity than the pristine MgAl LDH.