In this study, the performance of Fe3O4@CuCr-LDH@Fe-BTC nanocomposite as a novel adsorbent was evaluated for tetracycline (TC) removal from aqueous solution using ultrasonic irradiation. The nanocomposite was successfully prepared by in-situ growth of Fe-BTC over magnetic CuCr-LDH and characterized by different analyses. The effects of various operating conditions, i.e., adsorbent dosage, initial TC concentration, solution pH, and contact time on the adsorbent performance were assessed. The yield of sono-assisted adsorption of TC using the nanocomposite could increase up to 95.6 % due to the enhancement of the mass transfer rate, while this value decreased to 53.6 % under stirring. The adsorption kinetic followed with a pseudo-second-order model and the Langmuir isotherm was well fitted with equilibrium experimental data with a maximum adsorption capacity of 625.7 mg/g. Results from the thermodynamic study also indicated that the physical adsorption occurred with the heat of adsorption of 34 kJ/mol. The coexistence of inorganic anions revealed that TC adsorption suffered greater from divalent anions (SO2 4− ,CO2 3− ), in comparison with monovalent anions (Cl− ). The main mechanisms involved in TC uptake were electrostatic interactions, π-π and n-π interactions, hydrogen bonding, and metal complexation. The nanocomposite represented high stability during five successive reuses and could keep its excellent performance in real aqueous solutions. Moreover, the straightforward separation utilizing magnetic forces represents an additional remarkable characteristic, indicating the suitability of the synthesized nanocomposite for utilization under practical conditions.
