Li Qianfeng, Yang Shiying, Wu Sui, Fan Danyang
Key Laboratory of Marine Environment and Ecology, Ministry of Education, Qingdao, 266100, China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
Key Laboratory of Marine Environment and Ecology, Ministry of Education, Qingdao, 266100, China; Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering (MEGE), Qingdao, 266100, China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
Chemosphere. 2022 Jul;298:134280. doi: 10.1016/j.chemosphere.2022.134280. Epub 2022 Mar 10.
Recently, mechanical ball milling (BM), a simple and green powder processing method, has been successfully applied to improve the performance of zero-valent metals (ZVMs) for efficient water treatment. However, until now BM is still regarded as a "black box" in which the processes of the solid-state reaction during activation remain unclear. In this paper, firstly, FeSO·7HO crystal was used to activate and modify inert microscale zero-valent aluminum (mZVAl) by BM to synthesize Al-Fe (oxide) composite that showed superior reactivity in reductive removal of various contaminants and excellent reusability, which may be mainly ascribed to the newly formed iron oxide layer on mZVAl by mechanochemical reaction. At the same time, the formation of iron oxides on mZVAl was closely related to BM parameters. Further kinematic analysis revealed that the occurrence of mechanochemical reaction depended on the impact energy and input energy, which BM speed and BM time were two main factors determining reaction extent on the premise that the precursors were full dose. Moreover, kinetic fitting uncovered the solid-state reaction mechanism between mZVAl and FeSO·7HO conformed to three-dimensional diffusion and phase boundary reaction models. This study ponders deeply upon the mechanochemical process and solid reaction mechanism during the preparation of Al-Fe (oxide) composite, which deepens comprehensions of material synthesis procedures by BM and promotes applications of ZVM-based composite in polluted water or wastewater treatment.
最近，机械球磨（BM）作为一种简单且绿色的粉末加工方法，已成功应用于提高零价金属（ZVMs）在高效水处理中的性能。然而，到目前为止，BM仍被视为一个“黑匣子”，其中活化过程中的固态反应过程尚不清楚。本文首先采用FeSO·7H₂O晶体通过BM对惰性微米级零价铝（mZVAl）进行活化和改性，合成了Al-Fe（氧化物）复合材料，该复合材料在还原去除各种污染物方面表现出优异的反应活性和出色的可重复使用性，这可能主要归因于通过机械化学反应在mZVAl上新形成的铁氧化物层。同时，mZVAl上铁氧化物的形成与BM参数密切相关。进一步的动力学分析表明，机械化学反应的发生取决于冲击能量和输入能量，在反应物剂量充足的前提下，BM速度和BM时间是决定反应程度的两个主要因素。此外，动力学拟合发现mZVAl与FeSO·7H₂O之间的固态反应机理符合三维扩散和相边界反应模型。本研究深入思考了Al-Fe（氧化物）复合材料制备过程中的机械化学过程和固相反应机理，加深了对BM材料合成过程的理解，并促进了基于ZVM的复合材料在污染水或废水处理中的应用。
