A Novel Catalytic System Utilizing Cobalt-Based Metal- Organic Framework for Peroxymonosulfate Activation in Congo Red Degradation

Abstract Cobalt metal-organic framework (Co-MOF), a crystalline porous material self-assembled from Co metal via organic ligand bridging, has received increasing attention due to its multi-metal sites and its efficient azo-fuel degradation properties. In this study, a Co-MOF was synthesized and used to activate the degradation of Congo red (CR) by peroxomonas sulphate (PMS). Demonstrating that the degradation efficiency of the Co-MOF/PMS system reached close to 100% for 20 mg/L CR within 10 min at a catalyst dosage of 0.30 g/L and a PMS dosage of 0.5 mM. Quenching experiments and mass spectrometry elucidated two different degradation pathways of CR: (i) radical pathway: hydroxyl radical (•OH) and sulfate radical (SO4•−); (ii) non-radical pathway: singlet oxygen (1 O2). The degradation products were examined by liquid chromatography-mass spectrometry (LC-MS) and possible transformation pathways for transformation. This work underscores the immense potential of the Co-MOF/PMS system as an efficient catalyst for environmental remediation, leading to significant advances in CR degradation and wastewater treatment technologies.