In-situ growth of MOFs on porous geopolymer spheres for continuous-flow PMS degradation of antibiotics

A metakaolin/slag-based porous geopolymer (non-sintered ceramic) was prepared using a simple direct molding method, and Cu-MOFs were grown in situ via a solvothermal process. The Cu-MOFs/GP composites achieve a ~98% degradation rate for tetracycline hydrochloride within 10 minutes via peroxymonosulfate (PMS) activation at pH 11. Radicals (•OH, SO₄•⁻, O₂•⁻) and non-radicals (¹O₂) were identified as the dominating reactive oxygen species (ROSs) participated in the catalytic process. Cu-MOFs/GP acts as an electron transfer medium between tetracycline molecules and PMS molecules, enabling the efficient degradation of tetracycline. Furthermore, the catalytic system exhibited excellent cyclic stability, pH adaptability, and resistance to ionic interference, demonstrating superior performance in a flow-through fixed-bed reactor simulating real wastewater. The practical application of this system in wastewater treatment can be beneficial for reducing energy consumption, enhancing environmental sustainability, and lowering catalyst costs.