Remediation of pharmaceutical contaminated water by use of magnetic functionalized metal organic framework. Physicochemical study of doxycycline adsorption

The presence of pharmaceutical pollutant, doxycycline (DOC) in water and waste streams has negative impact on the environment. In this research, metal organic framework was synthesized and functionalized by potassium nickel ferrocyanide (KNiFC). After characterisation, the functionalized adsorbent was used for removal of DOC from aqueous solutions. The adsorbent containing 80% of KNiFC exhibited the high adsorption capacity of 100 mg/g. The adsorption process was kinetically fast and the equilibration was established within 30 min. The used adsorbent retained 90% of its initial capacity after regeneration. The magnetic susceptibility of the adsorbent measured by VSM technique was 35 emu/g and sufficient for separation of the used adsorbent by external magnetic field. Isotherm models including Langmuir, Freundlich, Tempkin, Redlich-Peterson, and Sips were applied to correlate the experimental equilibrium data. To evaluate the fitness of the isotherm equations error analysis methods, residual root mean square error and average relative error were used.