文獻名： Ultrasound-assisted leaching of rare earths from the weathered crust elution-deposited ore using magnesium sulfate without ammonia-nitrogen pollution
作者： Shaohua Yina, Jiannan Peia, Feng Jianga, Shiwei Lia, Jinhui Penga, Libo Zhanga, Shaohua Jua, Chandrasekar Srinivasakannanb
aFaculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650093, China
bChemical Engineering Program, The Petroleum Institute, Abu Dhabi, P.O. Box 253, United Arab Emirates
摘要：The in situ leaching process of China's unique ion-adsorption rare earth ores has caused severe environmental damages due to the use of (NH4)2SO4 solution. This study reports that magnesium sulfate (MgSO4) as a leaching agent would replace (NH4)2SO4 by ultrasonically assisted leaching to deal with the ammonia-nitrogen pollution problem and enhance leaching process. At leaching conditions of 3 wt% MgSO4 concentration, 3:1 L/S ratio and 30 min, the total rare earth leaching efficiency reaches 75.5%. Ultrasound-assisted leaching experiments show that the leaching efficiency of rare earths is substantially increased by introducing ultrasound, and nearly completely leached out after two stage leaching process. Thus, ultrasonic-assisted leaching process with MgSO4 is not only effective but also environmentally friendly, and beneficial to leach rare earths at laboratory scale.
