The existing technologies to control Hg emissions from coal-fired power plants can be improved to achieve the centralized control of Hg0 emissions, which continue to pose a risk of Hg exposure to human populations. In this work, MoSx@γ-Fe2O3, formed by the sulfuration of phosphomolybdic acid (HPMo)-grafted γ-Fe2O3, was developed as a magnetic and regenerable sorbent to recover gaseous Hg0 from coal-fired flue gas as a cobenefit to the use of wet electrostatic precipitators. The thermal stability of γ-Fe2O3 was notably enhanced by HPMo grafting; thus, the magnetization of MoSx@γ-Fe2O3 hardly decreased during the application. The kinetic analysis indicates that the chemical adsorption of gaseous Hg0 was mainly dependent on the amounts of surface S22- and surface adsorption sites. Although the amount of S22- on sulfurated γ-Fe2O3 decreased after HPMo grafting, the amount of surface adsorption sites significantly increased due to the formation of a layered MoSx structure on the surface. Therefore, the ability of sulfurated γ-Fe2O3 to capture Hg0 was improved considerably after HPMo grafting. Furthermore, low concentrations of gaseous Hg0 in coal-fired flue gas can be gradually enriched by at least 1000 times by MoSx@γ-Fe2O3, which facilitates the recovery and centralized control of gaseous Hg0 in flue gas.

中文翻译：

---

硫代γ-Fe2O3上磷钼酸接枝显着提高燃煤烟气中气态元素汞的回收率：性能和机理。

可以改进控制燃煤电厂汞排放的现有技术，以实现对汞排放的集中控制，而汞排放继续给人类带来汞暴露的风险。在这项工作中，通过将磷钼酸（HPMo）接枝的γ-Fe2O3硫化而形成的MoSx @γ-Fe2O3被开发为一种磁性可再生吸附剂，可从燃煤烟气中回收气态Hg0，作为使用的好处。湿式静电除尘器。HPMo接枝显着提高了γ-Fe2O3的热稳定性。因此，在使用过程中，MoSx @γ-Fe2O3的磁化几乎不会降低。动力学分析表明，气态Hg0的化学吸附主要取决于表面S22-和表面吸附位点的数量。尽管HPMo接枝后硫化γ-Fe2O3上的S22-含量降低，但由于在表面形成了一层MoSx结构，表面吸附位点的数量明显增加。因此，HPMo接枝后，硫化γ-Fe2O3捕获Hg0的能力大大提高。此外，MoSx @γ-Fe2O3可将燃煤烟气中的低浓度气态Hg0逐渐富集至少1000倍，这有利于烟气中气态Hg0的回收和集中控制。