Carbon aerogel from forestry biomass as a peroxymonosulfate activator for organic contaminants degradation

The carbon catalyst has been widely used as a peroxymonosulfate (PMS) activator to degrade organic contaminants. The biomass carbon aerogel (CA) derived from poplar powder was synthesized in this study. CA with three-dimensional structure exhibited an excellent degradation performance of PMS activation for different types of organic contaminants including bisphenol A (BPA), rhodamine 6 G, phenol, and p-chlorophenol with the removal efficiencies up to 91%, 100%, 100%, and 60% within 60 min, respectively. It was found that singlet oxygen (1O2) dominated the non-radical pathway worked for BPA removal in CA/PMS system. The possible mechanism for PMS activation was discussed. A portion of 1O2 was produced through the transformation of superoxide radical (O2•-) in CA/PMS system. Electronic impedance spectroscopy (EIS) proved that the hierarchical structure of CA contributed to the electron transfer process for PMS activation. The ketonic/carbonyl groups (C˭O) on the surface of CA could serve as a possible active site to facilitate the generation of 1O2. In addition, CA showed superior degradation performance in actual water bodies and reusability with high-temperature regeneration treatment. This study developed an efficient and environmentally benign catalyst for water remediation of organic pollutants.