Use of magnetic yttrium alginate beads for tetracycline removal

In this study, magnetic yttrium alginate (m-Y@Alg) beads were prepared using magnetic Fe3O4 and alginate and rare earth element yttrium (Y). Y element was used as a crosslinker for the formation of m-Y@Alg beads. The use of these prepared beads in tetracycline removal was investigated. For this purpose, the best adsorption conditions were determined, and these conditions were pH:5, contact time (t):80 min, m-Y@Alg bead amount (m):10 mg, initial tetracycline concentration (C0):5 mg/L, temperature (T):25 °C. Adsorption isotherm, kinetic and thermodynamic studies were carried out under the determined best adsorption conditions. The adsorption process was found to be compatible with the single-layer Langmuir isotherm and the maximum adsorption capacity for the adsorption of tetracycline by m-Y@Alg beads was calculated as 16.24 mg/g. The adsorption kinetics were found to be consistent with the pseudo-second-order kinetic model and the adsorption process was explained by intraparticle diffusion. The nature of the adsorption reaction was determined to be spontaneous, endothermic and increasingly random in adsorption thermodynamic studies. The reusability of m-Y@Alg beads was tested in 15 consecutive adsorption/desorption studies and it was determined that these beads could be used effectively. In summary, it can be stated that m-Y@Alg beads, which have advantages such as simple preparation, reusability and naturalness, are effective in tetracycline adsorption.