Development and characterization of hydroxyapatite layered lanthanum organic frameworks by template method for defluoridation of water.

The template preparation of hydroxyapatit (HAp) layered lanthanum-benzene tricarboxylic acid based metal organic frameworks (La-BTC MOFs) abbreviated as HAp-La-BTC-MOFs has been investigated here for defluoridation of water. The nucleation and growth of La-based MOFs was carried out in the prepared HAp hard template using layer-by-layer (LBL) technique. The coulomb and chelation contacts on HAp surface between Ca2+ ions and COO- organic ligands of La-BTC MOFs play vital roles in the preparation process. The batch experiments were employed to assess the defluoridation capacity (DC) of HAp-La based MOFs. The physicochemical properties of HAp-La based MOFs were investigated by various instrumentation techniques. To identify the nature, order and feasibility of HAp-La based MOFs towards defluoridation was examined by adsorption kinetics, isotherms and thermodynamics studies. The mechanism of defluoridation using HAp-La based MOFs were explained in detail. The field and reusability investigations of HAp-La-BTC MOFs also explored to find the potential applicability.