A natural manganese ore as a heterogeneous catalyst to effectively activate peroxymonosulfate to oxidize organic pollutants

摘要

Heterogeneous transition metal catalysts are indispensable in improving environmental pollution.However,their fabrication is often costly and cumbersome,and they can easily pollute the environment.This study proposed using a natural Gabonese ore(GBO)containing Mn_(x)O_(y) and FexOy as catalysts to degrade orange Ⅱ(OII)via peroxymonosulfate(PMS)activation.The GBO+PMS system exhibited extraordinarily high stability and catalytic activity towards OII elimination(92.2%,0.0453 min^(−1)).The reactive oxygen species(ROS)generated in the system were identified using radical scavenging tests and electron spin-resonance(ESR)analysis.Singlet oxygen(^(1)O_(2))represented the dominant reactive species for OII degradation,while the system presented a lower reaction energy barrier and was effective in a broad pH range(2-10).This work also proposed the activation mechanism for the GBO+PMS system and OII degradation pathways.This study revealed a new approach for exploring inexpensive,eco-friendly,efficient,and stable heterogeneous transition metal catalysts.