The mechanism of microwave -induced mineral transformation and stabilization of arsenic in realgar tailings using ferrous sulfate
The mechanism of microwave -induced mineral transformation and stabilization of arsenic in realgar tailings using ferrous sulfate
复制标题
微波诱导硫酸亚铁矿物转化及稳定雄黄尾矿中砷的机理
DOI：
10.1016/j.cej.2020.124732
复制
发表时间：
2020
影响因子：
15.1
通讯作者：
Crittenden John C.
中科院分区：
文献类型：
--
作者：
Zhao Zezhou;Zhang He;Wang Xin;Yao Dengke;Hou Huijie;Shi Yao;Chen Jing;Wang Linling;Ma Miao;Liu Jing;Crittenden John C.
The mechanism of MW irradiation for the enhancement of the long-term stability of arsenic (As) in FeSO4-treated realgar tailings was studied. The efficiency of As stabilization reached 99.5% in the MW-FeSO4-air system, 1.35–fold of that in the FeSO4-air system (71.8%). The increased As stability in realgar tailings was attributed to the enhanced transformation of more stable Fe–As minerals (e.g. symplesite) from unstable Ca/S–As minerals (pharmacolite and realgar). The oxidation of realgar was accelerated by reactive oxygen species (ROS) through the activation of molecular oxygen with FeIIof FeSO4due to the MW athermal effect in the MW-FeSO4-air system. H+ions from realgar oxidation and FeSO4hydrolysis facilitated the dissolution of pharmacolite. The released As was captured by the formed ferric oxyhydroxide. “Hot spots” on FeSO4in MW field initiated the microstructural evolution to Fe–As crystalline minerals due to the MW thermal effect. The introduction of FeSO4and oxygen promoted the generation of ROS and “hot spots” in MW field, which contributed to the transformation from Ca/S–As minerals to Fe–As crystalline minerals and was of great significance for the long-term stability of As in realgar tailings.
