Iron-based metal-organic framework derived pyrolytic materials for effective Fenton-like catalysis: Performance, mechanisms and practicability

In this study, a new catalyst was fabricated by pyrolysis under nitrogen atmosphere with MIL-53(Fe) as the precursor, and was applied to catalyze Fenton-like process. Effects of calcination temperature and pH on decontamination performance, and stability of materials were investigated. Under optimal conditions (calcination temperature of 500 degrees C and pH of 5.0), the new Fenton-like system remained low iron leaching, and achieved high pseudo-first-order rate constant of 0.0251 min-1 for bisphenol S (BPS) removal, which is much higher than those in MIL-53(Fe), and nano-Fe3O4 catalyzed Fenton-like systems. The superiority of the new catalyst for Fenton-like catalysis was attributed to high specific surface area, as well as formed Fe(II), coordinatively unsaturated iron center and the Fe-O/Fe-C compounds based on the analyses of characterizations. Furthermore, main active species for BPS degradation was identified as hydroxyl radicals, and total hydroxyl radical generation was determined by trapping experiments. The degradation pathways of BPS were also proposed by intermediates monitoring. Moreover, this catalyst showed good potential for practical application, according to the evaluation of reuse, different pollutants degradation, and BPS removal in real wastewater. We believe this study developed a new catalyst with high catalytic activity, high stability and wide application scope, and also sheds light on further development of metal-organic frameworks for Fenton-like catalysis.

Automated summary

In this study, a new catalyst was developed for Fenton-like catalysis with high activity and stability. The catalyst was fabricated through pyrolysis under nitrogen atmosphere using MIL-53(Fe) as the precursor. Under optimized conditions, the new Fenton-like system showed low iron leaching and achieved high removal rates of bisphenol S (BPS). The main active species for BPS degradation were identified as hydroxyl radicals. This catalyst also demonstrated good potential for practical application in real wastewater.