Effect of a Mechanochemical Process on the Stability of Mercury in Simulated Fly Ash. Part 1. Ball Milling
Effect of a Mechanochemical Process on the Stability of Mercury in Simulated Fly Ash. Part 1. Ball Milling
复制标题
DOI：
10.1021/acs.iecr.1c03783
复制
发表时间：
2021-10
影响因子：
4.2
通讯作者：
Xinze Geng;Weimeng Zhao;Qiang Zhou;Y. Duan;Tianfang Huang;Xiaoshuo Liu
中科院分区：
文献类型：
--
作者：
Xinze Geng;Weimeng Zhao;Qiang Zhou;Y. Duan;Tianfang Huang;Xiaoshuo Liu
机械化学是一种新型的汞稳定方法，在汞稳定领域具有广阔的应用前景。本文制备了模拟汞吸附饱和粉煤灰（SFA），并利用全向行星球磨机进行了机械化学稳定化（MC）。通过汞毒性浸出试验，探讨了球磨时间、球磨速度、球粒度、球/SFA质量比等不同MC稳定化工艺对SFA汞稳定化的影响。根据不同MC稳定化前后SFA的理化性质，探讨了其汞稳定化机理。结果表明，不同MC稳定条件对SFA汞稳定性的影响趋势不同。SFA的最佳MC稳定化工艺为：球磨时间为30 min，球磨速度为400 rpm，球尺寸为5 mm，球/SFA质量比为10/1。适当的MC工艺有利于汞在SFA中的稳定，因为MC工艺可以粉碎SFA颗粒，破坏其晶格结构，使其孔隙结构更加发达，产生更多的表面活性位点，有利于提高汞在SFA中的扩散率和吸附能力。然而，不当的MC工艺会导致SFA的团聚，降低其活性位点，破坏其孔隙结构，不利于汞的稳定，甚至导致二次释放。然而，尽管通过适当的MC稳定工艺可以提高SFA中汞的稳定性，但稳定性能仍然不足。
As a novel method, mechanochemistry has great potential in the field of mercury stabilization. In this paper, simulated mercury adsorption saturated fly ash (SFA) was prepared, and an omnidirectional planetary ball mill was used for mechanochemical (MC) stabilization. The effect of different MC stabilization processes such as ball milling time, ball milling speed, ball size, and the mass ratio of the ball/SFA on the mercury stabilization of SFA was explored by the mercury toxicity leaching experiment. Based on the physicochemical properties of SFA before and after different MC stabilization, the mercury stabilization mechanism was discussed. The results show that the influence trends of different MC stabilization conditions on the mercury stability of SFA are different. The optimum MC stabilization process of SFA is as follows: the ball milling time is 30 min, the ball milling speed is 400 rpm, the ball size is 5 mm, and the mass ratio of the ball/SFA is 10/1. An appropriate MC process is beneficial for the stabilization of mercury in SFA because it crushes SFA particles and destroys the lattice structure, making its pore structure more developed and more surface active sites generated, which is conducive to increasing the diffusivity and adsorption ability of Hg in SFA. However, an improper MC process induces agglomeration, reduces the active sites of SFA, and destroys its pore structure, which is not conducive to the stabilization of mercury and even leads to secondary release. Nevertheless, although the mercury stability in SFA can be improved by an appropriate MC stabilization process, the stabilization performance is still insufficient.