Phys.org September 24, 2024 Iron oxide-apatite (IOA) deposits have substantial rare earth elements potential, but their rare earth element (REE) enrichment mechanisms remain uncertain. An international team of researchers (Australia, China) used novel layered piston-cylinder experiments to address these questions. Seventeen magmatic FeP–Si immiscibility experiments, across 800–1150 °C, and at 0.4 and 0.8 GPa, reproduced many natural textural and geochemical features of IOA deposits. Magmatic-hydrothermal fluid bubbles and iron oxide-bubble pairs also formed. The results strongly supported FeP–Si immiscibility as a controlling factor in IOA deposits, although not mutually exclusive with other models. Light REE partition into FeP liquids, preferentially […]
Category Archives: Rare earth elements
DARPA Seeks Input on Novel Methods to Separate, Purify Rare Earth Elements
DARPA News July 12, 2023 Rare Earth Elements (REEs) comprise 17 elements, including scandium, yttrium, and the lanthanide series. REE extraction, separation, and purification from a complex feedstock can be environmentally degrading, energy inefficient, and difficult to permit in the United States. DARPA is sponsoring a hybrid workshop, to be held on Tuesday, July 25, 2023 to provide an overview and facilitate technical discussion regarding the Separation and Purification of Rare Earth Elements (SPREE) Advanced Research Concept (ARC) opportunity. The SPREE ARC opportunity is soliciting ideas to explore the following question: How can we purify Department of Defense (DoD)-relevant REEs […]
A dozen exotic bacteria are found to passively collect rare earth elements from wastewater
Phys.org February 28, 2023 Biosorption of metal ions by phototrophic microorganisms is regarded as a sustainable and alternative method for bioremediation and metal recovery. Researchers in Germany optimized the conditions of rare earth elements (REE) uptake by the cyanobacterial biomass and characterized the most important chemical mechanisms for binding them. They found the highest absorption capacity of lanthanum, cerium, neodymium, and terbium by 12 strains of cyanobacteria in laboratory culture. Biosorption depended strongly on acidity: it was highest at a pH of between five and six and decreased steadily in more acid solutions. They could adsorb amounts of REEs corresponding […]
Critical materials: Researchers eye huge supply of rare-earth elements from mining waste
Science Daily March 14, 2019 Large amounts of REEs (Rare-Earth Elements) exist in phosphogypsum (PG), a waste product from producing phosphoric acid, used in the production of fertilizers and other products, from phosphate rock. To extract REEs from PG waste a team of researchers in the US (Rutgers University, Idaho National Laboratory, industry, UC Davis, Lawrence Livermore National Laboratory) doped synthetic phosphogypsum with six rare-earth elements — yttrium, cerium, neodymium, samarium, europium and ytterbium. They found that a mixture of chemicals produced by the bacterium Gluconobacter oxydans was efficient in recovering REEs by bioleaching. Bioleaching is less harmful to the […]