This study presents a novel approach to solve the problems of leaching and regeneration of metal–organic frameworks (MOFs) in water treatment. The researchers developed a modified MOF by encapsulating MIL-88(Fe) with alginate. The modified MOF was then used to activate sulfate radicals with sodium persulfate for the degradation of levofloxacin (LVX) in water. Various characterization techniques, including XRD, FTIR, BET, FESEM, TG and EDS mapping, confirmed the successful synthesis of the modified MOF and revealed its characteristic facets. The catalytic and adsorptive abilities of the modified MOFs were investigated and sodium persulfate was found to be more effective than hydrogen peroxide in the degradation of LVX. Optimal degradation conditions were determined at a pH of 3, a concentration of 2.5 mM Na2S2O8 and a catalyst dosage of 0.75 g/L. The researchers also found that higher temperatures improved the removal of LVX. The granulated MOF showed remarkable stability over five cycles, although the performance gradually decreased, indicating its potential for long-term applications in water treatment. The inhibitory properties of isopropyl alcohol and ethanol suggest that sulfate radicals rather than hydroxyl radicals are involved in the degradation of LVX. In addition, the functional groups of levofloxacin, including the piperazine ring, the carboxylic acid group and the fluorine substituents, were identified as potential initiation sites for oxidation.