Pollution sources, characteristics and environmental risk assessment of heavy metals in surface water and sediments of typical pyrite mine in Southwest China.

Abandoned mines, especially pyrite-rich ones, release acid mine drainage (AMD) with high acidity and excessive amounts of heavy metals, threatening regional ecosystems. Six samples of mine drainage, nine samples of surface water, and twelve samples of sediment were analyzed in this case study of the Dashu pyrite mine in southwest China. A comprehensive analysis of the pollution levels, pollution sources, and potential hazards of eight metals (Ni, Cd, Cu, Zn, Fe, Al, Pb, and Mn) that exceeded regulatory standards was conducted by monitoring 24 conventional and characteristic indicators.

The response and ecological implications between various sulfur forms and environmental factors in acid mine drainage.

The production of acid mine drainage (AMD) involves oxidation of FeS to SO, during which a variety of intermediate sulfur forms (SO, S, SnO, SO) are generated. This study aimed to characterize the spatiotemporal distributions of different forms and relationships to environmental factors. The sulfur form in AMD is mainly SO, and the metastable sulfur SO、SO、SO and S have only a small amount of accumulation in the cyclic transformation of sulfur.

Insights into the effects of natural pyrite-activated sodium percarbonate on tetracycline removal from groundwater: Mechanism, pathways, and column studies.

In-situ chemical oxidation based on sodium percarbonate (SPC) has received much attention for remediation of groundwater contaminated with organic pollutants due to the high efficiency, stable reaction, and sustainability of SPC. Currently, metal ions and their composite materials, are mainly employed for the activation of SPC. However, due to its narrow pH range, slow Fe/Fe circulation, and generation of refractory sludge, its application in groundwater is limited.