Simultaneously rapid degradation of phenylphosphonic acid and efficient adsorption of released phosphate in the system of peroxymonosulfate (PMS) and Co3O4-La2O2CO3/C derived from MOFs

A bifunctional Co3O4-La2O2CO3/C material was successfully fabricated via calcinating Co and La metal organic frameworks (MOFs) at 500 degrees C and employed to activate peroxymonosulfate (PMS) for simultaneous degradation of phenylphosphonic acid (PPOA) and adsorption of the released phosphate. 100% degradation of PPOA (100 mol L-1) was realized by PMS (1.2 mmol L-1) mediated with Co3O4-La2O2CO3/C (0.2 g L-1) at initial pH 7 within 60 min. Meanwhile, the produced phosphate was also completely removed. A series of characterization of the Co3O4-La2O2CO3/C material was conducted, and the main factors impacting PPOA degradation and phosphate adsorption were investigated. Co3O4-La2O2CO3/C also exhibited superb stability. During 4 cycles, the removal rates of PPOA and the produced phosphate maintained at approximately 100% and above 93%, respectively. The investigation of electron paramagnetic resonance and quenching tests revealed that sulfate radicals and hydroxyl radicals were reactive oxygen species and the former made the predominant contribution to the oxidation of PPOA. The possible degradation pathways of PPOA were further proposed by analyzing intermediates. This study not only offers a feasible strategy for the safe disposal of organophosphorus and the released phosphate, but also extends the development of MOFs for the preparation of functional materials.