School of Earth Science and Engineering, Hohai University, Fo Cheng Xi Road 10, Nanjing, 21180, China.
Department of Soil Science and Agricultural Engineering, Biosystems and Environmental Engineering Research Group, Faculty of Agriculture, University of Zimbabwe, P.O. Box MP207, Mount Pleasant, Harare, Zimbabwe.
Sci Rep. 2021 Jan 27;11(1):2326. doi: 10.1038/s41598-021-81649-y.
The role of pyrite (FeS) in the process of water treatment using metallic iron (Fe) was investigated. FeS was used as a pH-shifting agent while methylene blue (MB) and methyl orange (MO) were used as an indicator of reactivity and model contaminant, respectively. The effect of the final pH value on the extent of MB discoloration was characterized using 5 g L of a Fe specimen. pH variation was achieved by adding 0 to 30 g L of FeS. Quiescent batch experiments with Fe/FeS/sand systems (sand loading: 25 g L) and 20 mL of MB were performed for 41 days. Final pH values varied from 3.3 to 7.0. Results demonstrated that MB discoloration is only quantitative when the final pH value was larger than 4.5 and that adsorption and co-precipitation are the fundamental mechanisms of decontamination in Fe/HO systems. Such mechanisms are consistent with the effects of the pH value on the decontamination process.
研究了黄铁矿（FeS）在使用金属铁（Fe）进行水处理过程中的作用。FeS 被用作 pH 值调节剂，而亚甲基蓝（MB）和甲基橙（MO）分别被用作反应性指示剂和模型污染物。使用 5 g L 的 Fe 样品来表征最终 pH 值对 MB 褪色程度的影响。通过添加 0 至 30 g L 的 FeS 来实现 pH 值的变化。在 Fe/FeS/砂系统（砂负荷：25 g L）和 20 mL MB 的静态批量实验中进行了 41 天。最终 pH 值从 3.3 变化到 7.0。结果表明，只有当最终 pH 值大于 4.5 时，MB 褪色才是定量的，并且吸附和共沉淀是 Fe/HO 系统中去污的基本机制。这些机制与 pH 值对去污过程的影响一致。
