Chitosan coated Fe3O4@Cd-MOF microspheres as an effective adsorbent for the removal of the amoxicillin from aqueous solution.

In this work, for the first time, a new magnetic cadmium-based MOFs (Fe3O4@Cd-MOF) was successfully synthesized in a green way and then modified with chitosan (CS) in the microsphere form (Fe3O4@Cd-MOF@CS). The obtained materials were fully characterized by several techniques. In the following, the efficiency of Fe3O4@Cd-MOF@CS was explored for the removal of amoxicillin (AMX). The outcome of the adsorption study showed that the removal efficiency is affected by CS and reaches its optimum at pH 8 and contact time of 240 min. Under optimized conditions, over 75% of AMX was removed. The kinetic and the isotherm of the adsorption were fit with the pseudo-second-order model and the Langmuir adsorption isotherm respectively. Eventually, the maximum adsorption capacity was obtained ~103.09 mg/g. Interestingly, these findings convince that the newly prepared Fe3O4@Cd-MOF@CS could be proposed as a promising magnetically separable adsorbent for antibiotic contaminants removal from the aqueous solution.