School of Energy and Environmental Engineering, University of Science and Technology Beijing, , Beijing, 100083, China.
State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing, 100083, China.
Environ Sci Pollut Res Int. 2024 Apr;31(20):29656-29668. doi: 10.1007/s11356-024-32995-7. Epub 2024 Apr 8.
The substantial amount of mercury emissions from coal-fired flue gas causes severe environmental contamination. With the Minamata Convention now officially in force, it is critical to strengthen mercury pollution control. Existing activated carbon injection technologies suffer from poor desulfurization performance and risk secondary-release risks. Therefore, considering the potential industrial application of adsorbents, we selected cost-effective and readily available activated coke (AC) as the carrier in this study. Four metal selenides-copper, iron, manganese, and tin-were loaded onto the AC to overcome the application problems of existing technologies. After 120 min of adsorption, the CuSe/AC exhibited the highest efficiency in removing Hg, surpassing 80% according to the experimental findings. In addition, the optimal adsorption temperature window was 30-120 °C, the maximum adsorption rate was 2.9 × 10 mg·g·h, and the effectiveness of CuSe/AC in capturing Hg only dropped by 5.2% in the sulfur-containing atmosphere. The physicochemical characterization results indicated that the AC surface had a uniform loading of CuSe with a nanosheet structure resembling polygon and that the Cu-to-Se atomic ratio was close to 1:1. Finally, two possible Hg reaction pathways on CuSe/AC were proposed. Moreover, it was elucidated that the highly selective binding of Hg with ligand-unsaturated Se was the key factor in achieving high adsorption efficiency and sulfur resistance in the selenium-functionalized AC adsorbent. This finding offers substantial theoretical support for the industrial application of this adsorbent.
燃煤烟气中大量的汞排放会导致严重的环境污染。随着《水俣公约》的正式生效，加强汞污染控制至关重要。现有的活性炭喷射技术存在脱硫性能差和二次释放风险的问题。因此，考虑到吸附剂具有潜在的工业应用价值，我们选择了具有成本效益且易于获得的活性炭（AC）作为载体。本研究将四种金属硒化物——铜、铁、锰和锡——负载到 AC 上，以克服现有技术的应用问题。经过 120 分钟的吸附，CuSe/AC 对 Hg 的去除效率最高，达到 80%以上。此外，最佳吸附温度窗口为 30-120°C，最大吸附速率为 2.9×10mg·g·h，CuSe/AC 在含硫气氛中的捕获 Hg 效率仅下降 5.2%。物理化学特性表明，AC 表面均匀负载有纳米片结构的 CuSe，类似于多边形，Cu 与 Se 的原子比接近 1:1。最后，提出了两种可能的 Hg 在 CuSe/AC 上的反应途径。此外，还阐明了 Hg 与配位不饱和 Se 的高选择性结合是实现高吸附效率和抗硫性能的关键因素，这为该吸附剂的工业应用提供了重要的理论支持。
