Investigation on structural and adsorptive features of BaO modified zeolite powders prepared by ball milling technique: Removal of tetracycline and various organic contaminants

Abstract

In the current study, the removal of tetracycline (TC) antibiotic via BaO-doped zeolite (80BaO@zeolite), which synthesized by ball-mill technique, from water by adsorption process was studied. The structure and properties of 80BaO@zeolite was determined by XRD, FTIR, SEM and BET/N2. TC adsorption capacity of 71.4 mg g−1 was obtained for 80BaO@zeolite. The Langmuir isotherm model was found to be compatible for 80BaO@zeolite. The kinetic results indicate that the adsorption rate is compatible with the pseudo second order model and the time for the adsorption to reach equilibrium was achieved as 360 min. Maximum TC removal was obtained at pH:10, in the presence of NaCl and CaCl2 salts, and compared to in tap water drinking water and distilled water. The sorption process has shown thermodynamically exothermic and spontaneous nature. The desorption of TC molecules attached to the 80BaO@zeolite surface was investigated using different eluents. The 88% TC removal and 94% TC recovery rates achieved in the first cycle with the 1 M NaOH eluent decreased to 72% and 70%, respectively, in the fourth cycle. High adsorption capacities of 161.3 mg g−1, 59.3 mg g−1 and 85.5 mg g−1were obtained in the removal of malachite green, murexide and basic violet-16, respectively.