ORAL

SESSION: Non-ferrousWedAM-R1	Barrios International Symposium on Sustainable Non-ferrous Smelting and Hydro/Electrochemical Processing (5th Intl. Symp. on Sustainable Non-ferrous Smelting and Hydro/Electrochemical Processing)
Wed Oct, 25 2017	Room: Condesa II
Session Chairs: Christoph Sagadin; Mateus Lanna Borges de Moraes; Session Monitor: TBA

11:00: [Non-ferrousWedAM01]
Recovery of Rare Earth Elements from Acid Mine Drainage
Elaine Felipe¹ ; Gabriel Silva¹ ; Bruna Vidigal¹ ; Ana Claudia Ladeira¹ ; ¹Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, Brazil;
Paper Id: 198 [Abstract]

The recovery of rare earth elements (REEs) from acid mine drainage by cationic resins was investigated using batch experiments. The experiments were carried out with laboratory solution and with acid mine water enriched with REEs. The experimental conditions were: pH 1.3, 2.5 and 3.4, temperature 25±1⁰C, and the exchange resins were Dowex 50WX8 and Purolite C160. For the laboratory solution, it was observed that for all the REE, except cerium, the adsorption was > 85%. For the spiked acid water, the best results were obtained at pH 1.3 and the adsorption capacity of the resins for the REEs in mmol.g-1 are: Dowex 50WX8 (La=0.074, Y=0.067, Ce=0.079, Pr=0.077, Nd=0.077, Eu=0.070, Dy=0.070, Sm=0.074); Purolite C160 (La=0.074, Y=0.059, Ce=0.080, Pr=0.077, Nd=0.076, Eu=0.070, Dy=0.066, Sm=0.074). The highest adsorption was obtained for La, around 89% for both resins. The resins also adsorbed other elements from the spiked acid water, such as Mn, Ca, Mg, Zn and Al. The resins adsorbed less than 10 to 12% of these elements, considered as impurities. The total loading capacity of the resins is 0.668 mmol g-1 for Dowex 50WX8 and 0.643 mmol g-1 for Purolite C160. However, the results showed that the resins have similar adsorption capacity for the REE.

SESSION: Non-ferrousWedAM-R1	Barrios International Symposium on Sustainable Non-ferrous Smelting and Hydro/Electrochemical Processing (5th Intl. Symp. on Sustainable Non-ferrous Smelting and Hydro/Electrochemical Processing)
Wed Oct, 25 2017	Room: Condesa II
Session Chairs: Christoph Sagadin; Mateus Lanna Borges de Moraes; Session Monitor: TBA

11:30: [Non-ferrousWedAM02]
Recovery of Rare Earth Elements by Co-precipitation with Iron, Aluminum and Manganese (Hydr)oxides from Acid Mine Drainage
Mateus Lanna Borges De Moraes¹ ; Ana Flavia Marinho Saraiva² ; Ana Claudia Ladeira² ; ¹Comission Nacional de Energia Nuclear, Belo Horizonte, Brazil; ²Centro de Desenvolvimento da Tecnologia Nuclear, Belo Horizonte, Brazil;
Paper Id: 302 [Abstract]

In the actual global chain of high-tech products, such as smartphones or communication satellites, specific wavelength lasers, catalyzers, etc., rare earth elements (REE) are important raw materials. In 2015, the global estimated production was 124 kt, and China alone produced 105 kt. Although the production and demand for REE are well established, there is a worldwide effort to find new resources and technologies due to the high demand foreseen for these elements in the near future. Acid Mine Drainage (AMD) can be a secondary resource of REE, since it is a natural and continuous leaching process of rocks or waste piles. For example, in The Osamu Utsumi mine (Minas Gerais-Brazil) the AMD waters contain around 130 mg L-1 of total REE - the light ones being the majority. Considering a flow rate of 150 to 300 m3 h-1, it is expected to recover up to 468 to 936 kg of REE per day, what is quite considerable. In AMD waters, iron and manganese (hydr)oxides are ubiquitous minerals and their importance on the retention and transportation of U, REE and other metals is well known. Previous studies showed that some REE can be immobilized by iron (hydr)oxides in acid solutions, with posterior selective extraction. This study aims at concentrating the REE present in AMD waters by co-precipitating it with synthetic Fe, Al and Mn (hydr)oxides. AMD was simulated using a laboratory solution with pH = 2.6, sulfate content of 2 g L-1 and total REE content of ~130 mg L-1. Different amounts of FeCl3, Al2(SO4)3 and MnSO4 0.5 mol L-1 were added to the laboratory solution in order to reach distinct Fe:Al:Mn:REE molar ratios. The pH was adjusted to 6±0.3 using KOH 2 mol L-1. Results showed that for some experimental conditions, the effectiveness of the removal of REE were above than 90 %. It was obtained an amorphous solid phase with ~17% of REE oxides using a molar ratio of 16:0:4:1, with 98% of removal effectiveness. Further studies will focus on the increase of REE content in the solid phase, followed by the leaching of these elements with acid and saline solutions, aiming to obtain a REE concentrate.