Summary: | 碩士 === 國立成功大學 === 地球科學系 === 106 === The acid mine drainage (AMD) is a severe environmental problem in mining areas, e.g., Chin-Kua-Shih, northern Taiwan, because of its high acidity as well as abundant toxic elements, and sulfate contents. Nonetheless, rare earth elements (REEs), popular raw materials for modern industries, are found enriched in AMD. In this study, we provided two remediation methods to neutralize the water acidity and recover the REEs from the Chin-Kua-Shih AMD system. For one hand, laboratory precipitation experiments using fluidized bed reactor had successfully reduced the heavy metals and REEs concentration of AMD waters by adsorption processes; Meanwhile, the inserted carbonate neutralized the water pH from 2.8 to 5.1. On the other hand, laboratory batch adsorption experiments showed that BT9M (α-FeOOH-εMnO2), a by-product of FBR-fenton, could adsorb the REEs and toxic metals from the AMD waters. The adsorption isotherm model of cerium on BT9M fits well with the Freundlich isotherm model. The Freundlich constant, n 〈 1, and zeta potential of εMnO2 indicated that BT9M performed unfavorable adsorption in acidic solutions. Overall, this study has demonstrated reliable remediation and REEs recovery approaches for the AMD waters, that aims for developments in the future remediation projects.
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