Polygonatum kingianum Dregs Biochar Accelerated Fe(Ⅱ)/Fe(Ⅲ) Cycle in Pyrite for Efficient Activation of Peroxymonosulfate to Degrade Carbamazepine in Water
Carbamazepine (CBZ), a typical emerging contaminant, poses significant environmental and health risks due to its frequent detection, high toxicity, and resistance to conventional degradation. This study synthesized a composite material (PH-BC3-600) via high-temperature pyrolysis of mining waste pyrite and discarded Polygonatum kingianum dregs biochar. The composite was employed to activate peroxymonosulfate (PMS) for CBZ degradation. Results demonstrated that biochar incorporation provided pyrite with more active sites, achieving 88.19% removal of 2.5 mg·L−1 CBZ within 5 minutes, with excellent resistance to Cl−, NO3−, and humic acid. Quenching experiments confirmed the involvement of ·OH, SO4·−, 1O2, and e− in the degradation process. The biochar increased the content of highly reductive sulfur species (S2−, S2−2, Sn2−) in PH-BC3-600, facilitating the reduction of Fe(III) to Fe(II) and thereby enhancing PMS activation. Additionally, PH-BC3-600 exhibited lower iron leaching compared to traditional pyrite-based materials, overcoming a key drawback of conventional catalysts. This study highlights the promising potential of PH-BC3-600 for activating PMS in the treatment of emerging contaminants in water.