Metal–organic framework-derived carbon-based evaporator for activating persulfate to remove phenol in interfacial solar distillation

Abstract

ABSTRACT The migration of semi-volatile organic compounds (SVOCs), such as phenolic pollutants, during the interfacial solar distillation process is a serious threat to the safety of water quality. Sulfate radicals-based advanced oxidation process is introduced into interfacial solar distillation for SVOCs removal. In this work, metal organic frameworks (MOFs)-derived carbon coated iron material (Fe@C) decorated carbon evaporators with high Fenton-like catalytic performance were prepared by calcination of iron based-MOFs on metasequoia wood blocks. The results indicate that the MOFs-derived Fe@C-700 evaporator has a carbon-coated iron structure with abundant active sites. In the Fe@C-700/ peroxydisulfate (PDS) /light system, the removal rate of phenol (0.30 mmol/L) reached 95%, and only 5.7% of phenol transfer to distillation water after 240 minutes. Free radical trapping experiments and electron paramagnetic resonance (EPR) measurements confirmed the presence of both radical and non-radical pathways in the system with 1O2 and O2•− being the main active species. This work provides a feasible solution for designing iron-based catalysts based on MOFs for interfacial solar distillation process, and also discusses the synergistic effect between interfacial solar distillation and persulfate activation for achieving high-quality distilled water.