Efficient Removal of Levofloxacin Hydrochloride from Environment by UiO-66/CoSO4 Composites

In this work, a newly UiO-66/CoSO4 composite was prepared by introducing UiO-66 as precursor carrier. The morphology and structure of the presented UiO-66/CoSO4 composite were characterized by scanning electron microscopy, elemental analysis, specific surface area analysis and X-ray diffraction. The adsorption performance of UiO-66/CoSO4 towards levofloxacin hydrochloride (LV) in aqueous solution was investigated, and some parameters, such as pH value, temperature, contact time and initial concentration have been optimized. The results showed that the UiO-66/CoSO4 composite has significant adsorption performance for levofloxacin hydrochloride. Compared with the control material UiO-66, the removal efficiency of the composite towards levofloxacin hydrochloride increased by 20% under the same conditions, which indicated that the properties of the composites have been greatly improved. Within 5 min, 95.3% of levofloxacin hydrochloride can be removed, and the equilibrium adsorption (99.8%) was achieved within 30 min and the adsorption process could be described by pseudo-second-order kinetic model. The adsorption isotherm verified that the maximum adsorption capacity was up to 108.42 mg.g(-1) and fitted well with the Langmuir isotherm model, which indicated that monolayer coverage of levofloxacin hydrochloride was formed on the surface of UiO-66/CoSO4 composite. Data obtained from thermodynamic study showed that the adsorption process is spontaneous endothermic reaction and the chemical adsorption might play major role to control step. The UiO-66/CoSO4 composite was easy to prepare with good reusability, and the adsorption efficiency is still higher than 92.2% after five cycles. Additionally, under the optimized condition, the UiO-66/CoSO4 composite was successfully applied for the removal of levofloxacin hydrochloride from environmental water and soil samples. It was found that above 94.7% of target can be removed by the as-prepared UiO-66/CoSO4 composite. This result proved that the composite with excellent recognition has been synthesized. The new UiO-66/CoSO4 composite prepared in this work provided a way to treatment levofloxacin hydrochloride in environment with broad application prospect.