Investigating Abiotic and Biotic Mechanisms of Pyrite Reduction.

ABSTRACT: Pyrite (FeS₂) has a very low solubility and therefore has historically been considered a sink for iron (Fe) and sulfur (S) and unavailable to biology in the absence of oxygen and oxidative weathering. Anaerobic methanogens were recently shown to reduce FeS₂ and assimilate Fe and S reduction products to meet nutrient demands. However, the mechanism of FeS₂ mineral reduction and the forms of Fe and S assimilated by methanogens remained unclear. Thermodynamic calculations described herein indicate that H₂ at aqueous concentrations as low as 10^-10 M favors the reduction of FeS₂, with sulfide (HS^-) and pyrrhotite (Fe_{1- x} S) as products; abiotic laboratory experiments confirmed the r

SUBMITTER: Spietz RL 

PROVIDER: S-EPMC9124975 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature