Fast removal of bisphenol A by coconut shell biochar incorporated ?-MnO2 composites via peroxymonosulfate activation

In this study, a series of coconut shell biochars (CSB) with different pyrolysis temperature were prepared and incorporated with alpha-MnO2 for bisphenol A (BPA) degradation in water through activating peroxymonosulfate (PMS). The results showed that with the assistance of CSB, alpha-MnO2/CSB exhibited superior catalytic activity over pristine alpha-MnO2, in which CSB played multiple roles in the composite. Basically, CSB could effectively improve the dispersion and expose more active sites of alpha-MnO2. Besides, CSB could build solid interactions with alpha-MnO2 and boost the electron transferring rate between catalyst, PMS and BPA. Moreover, alpha-MnO2 and CSB were both enrolled in the generation of radical and non-radical species for BPA degradation. Having multiple active species, the alpha-MnO2/CSB composite could maintain high catalytic performance under a wide pH range with good reusability and adaptability. The existence of both radical and non-radical pathways was further verified through identifying the BPA degradation intermediates. This study provides a new insight for the design of novel composite catalyst for water decontamination using biochar as a multifunctional participant.

Automated summary

In this study, coconut shell biochars (CSB) with different pyrolysis temperature were prepared and incorporated with alpha-MnO2 for the degradation of bisphenol A (BPA) in water. The presence of CSB significantly improved the catalytic activity of alpha-MnO2 by improving its dispersion, exposing more active sites, and enhancing electron transfer rate. The composite of alpha-MnO2/CSB showed good performance under a wide pH range and had both radical and non-radical pathways for BPA degradation. The study provides new insights into the design of composite catalysts for water decontamination using biochar.