Redox reaction of aqueous selenite with As-rich pyrite from Jiguanshan ore mine (China): Reaction products and pathway

Influence of Surface Compositions on the Reactivity of Pyrite toward Aqueous U(VI)

“…The As-pyrite blocks were crushed, sieved, and magnetically separated in the air, following the procedures described previously. 4 A similar pretreatment was applied to the Si-pyrite blocks, while no pretreatment was carried out for the commercial Pb-pyrite. The sizes of the obtained particles were 1.5−4.8, 0.13−0.15, and 5.0−10.0 mm for Pb-pyrite, As-pyrite, and Si-pyrite, respectively.…”

“…30 Preferential release of As impurities via arsenopyrite oxidation has previously been observed for Asrich pyrite oxidation by aqueous Se(IV). 4 Unlike As impurities, the pyrite lattice does not readily accommodate Pb at high concentrations, and the Pb content of pyrite was attributed to the presence of nanoscale inclusions of Pb-bearing minerals such as galena. 28 Previous studies indicated that galena has priority over pyrite for U(VI) reduction, 23,63 which further supports our study that the Pb-rich area on the pyrite surface is the reactive site for U(VI) reduction.…”

“…1 Besides, pyrite can also be present in sulfide-rich blended cement that could be used as repository construction material. 2 Previous studies have confirmed that pyrite can effectively immobilize redox-sensitive radionuclides (such as 79 Se 3,4 and 99 Tc 5 ) via reductive precipitation. Uranium (U), accounting for 96 wt.% of the spent nuclear fuel and receiving extensive attention in the geological disposal of nuclear waste, 6-9 is also redox-sensitive and its solubility is largely dependent on its oxidation state.…”

“…Besides, pyrite can also be present in sulfide-rich blended cement that could be used as a repository construction material . Previous studies have confirmed that pyrite can effectively immobilize redox-sensitive radionuclides (such as 79 Se , and 99 Tc) via reductive precipitation.…”

The New Beamline LISA at ESRF: Performances and Perspectives for Earth and Environmental Sciences

“…Among the published works based on measurements performed at the beamline in the last few years, we point out the investigation of Tl contamination of the drinkable water from the public distribution system of Valdicastello Carducci-Pietrasanta (northern Tuscany, Italy) [9]; the study of As contamination of floodplain soils and groundwater from shallow aquifers [10,11]; the study of Fe chemical environment in asbestos and erionite mineral fibers [12]; the investigation of selenium (Se) and lead (Pb) accumulation, distribution, and speciation in edible plants [13,14]; the Fe speciation in urban particulate matter and industrial quartz dusts [15,16]; the investigation of amorphous zinc (Zn) biomineralization ("white mud"), occurring at Naracauli stream, Sardinia [17]; the Sb speciation in brake linings, brake pad wear residues, road dust, and atmospheric particulate matter [18]; the interaction of As-rich natural pyrite with aqueous selenite [Se (IV)] [19], and As speciation in travertines [20].…”