Oxidation of pyrite and arsenopyrite in sulphidic spoils in Lavrion

Sulfide-driven arsenic mobilization from arsenopyrite and black shale pyrite

“…This may have resulted from the formation of iron oxide crusts on pyrite surfaces in the oxic treatments that slowed or prevented reactions of solid phase arsenic with sulfide (Komnitsas et al, 1995;Nesbitt et al, 1995;Schaufuss et al, 2000;Yu et al, 2004;Walker et al, 2006). In addition, the oxidation of sulfide was more rapid under oxic than hypoxic conditions decreasing sulfide's reactive lifetime.…”

“…The release of arsenic from arsenopyrite and arsenic-rich pyrite has been examined under oxidizing conditions (Komnitsas et al, 1995;Nesbitt et al, 1995;Nesbitt and Muir, 1998;Craw et al, 2003;Yu et al, 2004) and at the extremely low pH of acid mine drainage (Komnitsas et al, 1995;Yu et al, 2004), but not at neutral pH and under hypoxic or redox disequilibrium conditions where sulfide and oxygen or other oxidants may coexist due to biological activity and groundwater flow.…”

Framboidal and idiomorphic pyrite in the upper Maastrichtian sedimentary rocks at Gabal Oweina, Nile Valley, Egypt: Formation processes, oxidation products and genetic implications to the origin of framboidal pyrite

“…Komnitsas et al, 1995;Weber et al, 2004;Triantafyllidis and Skarpelis, 2006;Li et al, 2007). It has been described in terms of its occurrence and genesis in sedimentary rocks (e.g.…”

Arsenic in Natural Environments

“…Specifically, fractures and faults in rocks extending into the subsurface may result in oxidizing conditions to depths of 700 m (Arehart, 1996, 389). Coarse sediments and mining wastes have especially high permeabilities, which allow air and aerated water to readily infiltrate and contact buried sulfides (Mascaro et al, 2001;Komnitsas, Xenidis and Adam, 1995). Desiccation cracks or other fractures in otherwise low-permeability materials also provide routes for oxidizing liquids to migrate and react with buried sulfide minerals (Craw et al, 1999).…”