Sulfide-driven arsenic mobilization from arsenopyrite and black shale pyrite

The sources of geogenic arsenic in aquifers at Datong basin, northern China: Constraints from isotopic and geochemical data

“…11). Although As-rich pyrite has been found in different sites of high arsenic aquifers (Verplanck et al, 2008;Zhu et al, 2008), the majority of pyrite obtained from the study area contain arsenic less than 1 mg/kg in this study. Therefore, instead of pyrite, Fe oxides could be the major mineral phases of arsenic enrichment in the bedrocks at Datong.…”

Changes of arsenic fractionation and bioaccessibility in wastewater-irrigated soils as a function of aging: Influence of redox condition and arsenic load

“…In addition to the factors mentioned above, As loads and redox conditions such as aerobic or low oxygen conditions may also be important factors for the aging mechanisms of As in soils. Because the transformation of As species and soil components such as iron hydroxides and organic matter are generally affected by the redox conditions (Zhu et al, 2008;Frohne et al, 2011;Parsons et al, 2013;Ma et al, 2014;Han et al, 2015), and the fixation of As on soil minerals is significantly influenced by As loads due to the higher adsorption amount of As on soils with increasing As loads (Goh and Lim, 2004;Huang et al, 2013). As far as we know, however, the impact of redox conditions and As loads on the aging process of As in Chinese irrigated soils has received little attention.…”

Arsenic Geochemistry of Acid Mine Drainage

“…This was shown by Zhu (2010) with arsenical pyrites of the Newark basin, in New Jersey, USA, where As release was seven times greater in bacterially-controlled reactors than abiotic release. The mobilization continued for &4 weeks, while As release stopped after only 2 days in abiotic sulphide exchange conditions (Zhu et al 2008). Active bacterial leaching of As by T. ferrooxidans (which was subsequently renamed A. ferrooxidans) from sulfidic gold mine material was reported by Luong et al (1985) in Alaska, USA, and Yukon, Canada.…”

“…16 and 17). Arsenic mobilization from FeAsS is also triggered by exchange with aqueous sulphide (Zhu et al 2008). This sulphide-arsenide exchange reaction results in greater As release than normal O 2 oxidation reactions.…”