School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
Environ Sci Technol. 2023 Jul 25;57(29):10882-10890. doi: 10.1021/acs.est.3c03411. Epub 2023 Jul 12.
Gaseous elemental mercury (Hg) extraction from industrial flue gases is undergoing intense research due to its unique properties. Selective adsorption that renders Hg to HgO or HgS over metal oxide- or sulfide-based sorbents is a promising method, yet the sorbents are easily poisoned by sulfur dioxide (SO) and HO vapor. The Se-Cl intermediate derived from SeO and HCl driven by SO has been demonstrated to stabilize Hg. Thus, a surface-induced method was put forward when using γ-AlO supported selenite-chloride (SeO-Cl, named Se-Cl) for mercury deposition. Results confirmed that under 3000 ppm SO and 4% HO, Se-2Cl exhibited the highest induced adsorption performance at 160 °C and higher humidity can accelerate the induction process. Driven by SO under the wet interface, the in situ generated active Se has high affinity toward Hg, and the introduction of Cl enabled the fast-trapping and stabilization of Hg due to its intercalation in the HgSe product. Additionally, the long-time scale-up experiment showed a gradient color change of the Se-2Cl-induced surface, which maintained almost 100% Hg removal efficiency over 180 h with a normalized adsorption capacity of 157.26 mg/g. This surface-induced method has the potential for practical application and offers a guideline for reversing the negative effect of SO on gaseous pollutant removal.
气态元素汞（Hg）因其独特的性质，正在从工业烟道气中进行提取的深入研究。选择性吸附将 Hg 转化为 HgO 或 HgS 是一种很有前途的方法，但吸附剂很容易被二氧化硫（SO）和 HO 蒸气中毒。SO 驱动下的 SeO 和 HCl 产生的 Se-Cl 中间体已被证明可以稳定 Hg。因此，在使用γ-AlO 负载的亚硒酸盐-氯化物（SeO-Cl，命名为 Se-Cl）进行汞沉积时，提出了一种表面诱导方法。结果证实，在 3000 ppm SO 和 4% HO 下，Se-2Cl 在 160°C 时表现出最高的诱导吸附性能，较高的湿度可以加速诱导过程。在湿界面下 SO 的驱动下，原位生成的活性 Se 对 Hg 具有高亲和力，而 Cl 的引入由于其在 HgSe 产物中的插层作用，实现了 Hg 的快速捕获和稳定。此外，长时间的放大实验显示了 Se-2Cl 诱导表面的梯度颜色变化，在 180 小时内保持了近 100%的 Hg 去除效率，归一化吸附容量为 157.26 mg/g。这种表面诱导方法具有实际应用的潜力，并为克服 SO 对气态污染物去除的负面影响提供了指导。
