Natural pyrite-stimulative periodate activation: efficiency and mechanism study

Natural pyrite (NP) is an alternative catalyst for wastewater purification via advanced oxidation processes (AOPs). However, the activation performance and mechanism of periodate (PI) by NP have not yet been revealed. Herein, this work examines the activation performance of NP towards PI and its application in the degradation of antibiotic wastewater. Interestingly, 95.69% of chlortetracycline (CTC) was degraded by NP within 20 min via PI activation. Besides, NP shows effective degradation of various pollutants such as rhodamine B (65.81%), sulfamethoxazole (89.04%), and sodium butylxanthate (99.77%) within 20 min. The active species quenching experiment suggested that the active species \(\bullet {\text{OH}}\) $\bullet \text{OH}$ , \({{\text{IO}}}_{3}\bullet\) ${\text{IO}}_3\bullet$ , ¹O₂ and the active complex of PI bonded with NP surface participated in CTC degradation. In addition, Fe(II) on NP surface is the main active site for PI activation, while S_n²⁻ species accelerates the reduction of Fe(III) to Fe(II) and promotes sustained PI activation. This work provides new ideas for the application of NP in environmental pollution control.