Synthesis, Characterization, Crystal Structure of Copper-glutamate Metal Organic framework (MOF) and its Adsorptive Removal of Ciprofloxacin Drug from Aqueous Solution
Therapeutic drug is an essential and indispensable element for life. Worldwide, antibiotics are widely used for therapeutic and prophylactic purposes in human and veterinary medicine. Consequently, they are persistently released into the environment as waste water from farm, hospital, domestic and industrial effluent. Researches proved the discharge and presence of therapeutic drug in wastewater treatment plants, rivers and lakes. Adsorption techniques are widely used for the removal of waste water pollutant due to easy operation, efficiency and environmentally friendly nature of the technique. [Cu(Glu)2 (H2O2)] .H2O MOF adsorbent was synthesized by reaction of Cu2+ with glutamic acid under mixing at room temperature in a ½ : 1 molar ratio. Characterization of the compound was done by elemental analysis, IR and UV-Vis spec, SEM and PXRD. The crystal structure is orthorhombic with space group of P212121. a= 7.2036 (5) Å. b = 10.2696 (7) Å. c= 11.0023 (8) Å. Z = 4. The coordination about the copper is octahedral, (6-coordinate geometry) involving four oxygen atom from the glutamic acid and one nitrogen from the amine of the glutamate. One lattice water molecule linked directly to the copper central metal in a terminal fashion and lattice water molecule is found outside the coordination sphere. IR and UV-Vis spectral support coordination of the metal with the ligand. SEM shows clearly that the compound is porous for adsorption The MOF was studied for the adsorption of aqueous Ciprofloxacin drug. Sorption data were subjected to adsorption isotherms and kinetics. The adsorption isotherm data can be best described by Temkin isotherm, this revealed the ability of [Cu(Glu)2(H2O)].H2O MOF to adsorb 61.35 mg of Ciprofloxacin drug/ gram of copper glutamate at 25 0C, pH 4.0. Freundlich sorption intensity support multi binding site of MOF. The kinetic of ciprofloxacin adsorption tails a pseudo-second-order kinetic model, signifying the presence of physi-sorption. Results suggested the use of [Cu(Glu)2(H2O)].H2O MOF as an adsorbent for removal of Ciprofloxacin from aqueous solution.