Knowledge Agora

Title	Remediation of acid mine drainage and immobilization of rare earth elements: Comparison between natural and residual alkaline materials
ID_Doc	15675
Authors	Kotte-Hewa, DJ; Durce, D; Salah, S; Cánovas, CR; Smolders, E
Title	Remediation of acid mine drainage and immobilization of rare earth elements: Comparison between natural and residual alkaline materials
Year	2023
Published
Abstract	Acid mine drainage (AMD) is a well-known source of toxic trace metals in freshwaters. Traditional passive treatment systems rely on AMD neutralization with limestone and removal of most common toxic transition metals such as Cu and Zn with little attention to rare earth elements (REE). Alkaline waste materials now receive increasing attention as low cost AMD treatment alternatives in the circular economy. This study was set up to identify the efficiency of alkaline waste materials remediating AMD and scavenging REE in addition to other toxic trace elements. An AMD sample was collected from a lixiviate coming from pyrite heaps in the Iberian Pyrite Belt (pH = 1.8, 30 mu M & sum;REY). The sample was treated with either blast furnace slag (BFS) generated during smelting of iron ore in a blast furnace or biomass ashes (BA) derived from combustion of biomass, thereby using analytical grade CaCO3, and NaOH as reference products. The batch alkalinization experiments were conducted by adding each alkaline material at an amount to obtain an equal pH to approximate to 6.5. The required amounts of the products were NaOH < CaCO399%) and the remaining REE concentrations in the solutions were clearly lower than values for Cu and Zn. The Zn and Cu removals were not consistently high enough (except with NaOH) to meet environmental limits in the discharge waters. The largest efficiency for REE removals was obtained with CaCO3. Indirect evidence here suggests that gypsum is a better host for the trivalent REE than Fe(III) minerals in the precipitates. The ionic radii of trivalent REE are more similar to Ca2+ than to Fe3+, explaining the better potential of gypsum as REE host. This study showed also the potential of BFS as alkaline agent for the remediation of AMD in terms of its higher alkalinity generation potential as compared to BA, thus making BA less promising than BFS.
PDF	https://doi.org/10.1016/j.apgeochem.2023.105800

Similar Articles

ID	Score	Article
12823		Hermassi, M; Granados, M; Valderrama, C; Ayora, C; Cortina, JL Recovery of rare earth elements from acidic mine waters: An unknown secondary resource(2022)
16760		Akinwekomi, V; Maree, JP; Masindi, V; Zvinowanda, C; Osman, MS; Foteinis, S; Mpenyana-Monyatsi, L; Chatzisymeon, E Beneficiation of acid mine drainage (AMD): A viable option for the synthesis of goethite, hematite, magnetite, and gypsum - Gearing towards a circular economy concept(2020)
26798		Bonnail, E; Vera, S; Blasco, J; Conradi, M; DelValls, TA Metal Pollution and Mining in the Iberian Pyrite Belt: New Remediation Technologies to Improve the Ecosystem Services of the River Basins(2023)Water, 15, 7
13431		Lima, AT; Ottosen, L Recovering rare earth elements from contaminated soils: Critical overview of current remediation technologies(2021)
16538		Ghani, J; Toller, S; Dinelli, E; Funari, V Impact and recoverability of metals from waste: a case study on bottom ash from municipal solid waste incineration plants(2023)
28997		Masindi, V; Foteinis, S; Renforth, P; Ndiritu, J; Maree, JP; Tekere, M; Chatzisymeon, E Challenges and avenues for acid mine drainage treatment, beneficiation, and valorisation in circular economy: A review(2022)
15181		Gómez-Arias, A; Yesares, L; Caraballo, MA; Maleke, M; Vermeulen, D; Nieto, JM; van Heerden, E; Castillo, J Environmental and geochemical characterization of alkaline mine wastes from Phalaborwa (Palabora) Complex, South Africa(2021)
16060		Helser, J; Perumal, P; Cappuyns, V Valorizing (cleaned) sulfidic mine waste as a resource for construction materials(2022)
5535		Masindi, V; Mbhele, R; Foteinis, S Sustainable Co-Management of Acid Mine Drainage with Struvite Synthesis Effluent: Pragmatic Synergies in Circular Economy(2023)Environments, 10, 4
24551		Sarker, SK; Pownceby, M; Yadav, S; Bruckard, W; Haque, N; Singh, N; Pramanik, BK Selective removal of Fe impurities in the recovery of rare earth elements from carbonatite tailings using chemical routes(2024)