Synthesis And Characterization Of Titanosilicate Compounds For Pb (Ii) Removal
Lead (Pb) is considered a highly toxic element to both human and environment. In this study, titanosilicate (TSi) compounds were synthesized and tested for removal of lead (Pb). The TSi sorbent was synthesized using sol-gel synthesis of titanium (IV)-isopropoxide (TiPO) and tetraethylorthosilicate (TEOS) mixed together with sodium hydroxide at various onditions. The adsorbents were characterized for their morphology and phases using scanning electron microscope and X-ray diffraction (XRD). The maximum Pb(II) adsorption capacities of the sorbents obtained are very high and in the range of 300-400 mg Pb /g sorbent. By analyzing the ratio of the released sodium ion from the sorbent to the ratio of the adsorbed Pb(II), the Pb(II) removal mechanisms are inferred to be mainly the ion-exchange. X-ray diffraction patterns show that the synthesized sorbents are mostly in the amorphous to the semi-crystalline phases. The sorbent in the semi-crystalline state was prepared by the sol-gel synthesis followed by hydrothermal treatment at 200°C for 6h and has the highest adsorption capacity. Further increase in hydrothermal time resulted in sorbent with crystalline structure, however, the sorption performance was reduced.
Keywords- Titanosilicate, Lead, Adsorption