Use of Coal Mining Waste for the Removal of Acidity and Metal Ions Al (III), Fe (III) and Mn (II) in Acid Mine Drainage

摘要

The coal industry may generate acid mine drainage (AMD) and mining wastes, which may adversely affect the quality of the environment. In this study we propose the use of this waste in the removal of acidity and metal ions, as well as in the reduction of the toxicity of AMD. A physico-chemical analysis of the waste shows the presence of mainly SiO_2, A1_2O_3 and Fe_2O_3, and a superficial area of 4.316 m~2 g~(-1). The treatment of AMD with the waste resulted in an increase in pH from 2.6 to 7.8 and removed 100% of the Al (Ⅲ), 100% of the Fe (Ⅲ) and 89% of the Mn (Ⅱ). We also observed that the high toxicity of the AMD towards Daphnia magna (LC_(50) = 3.68%) and Artemia sp. (LC_(50) = 4.97%) was completely eliminated after treatment with the waste. The data obtained allow us to propose that the waste can be used in the treatment of AMD, providing an economic use for the waste.