Recycling Lepidolite from Tantalum–Niobium Mine Tailings by a Combined Magnetic–Flotation Process Using a Novel Gemini Surfactant: From Tailings Dams to the “Bling” Raw Material of Lithium

Abstract

On January 25, 2019, the tailings dam at Vale's Coŕrego do Feijao mine (Brumadinho, Minas Gerais, Brazil) ruptured, releasing about 12 million cubic meters of tailings, killing over 240 people and posing a considerable and ongoing environmental hazard. Thus, the recovery of valuable minerals from tailings can contribute to a sustainable disposal of this hazardous residue, saving human lives and protecting the environment. The tailings of a tantalum−niobium mine usually contain a considerable amount of lepidolite resource. Nonetheless, the method of sustainably acquiring the lepidolite resource from tailings of a tantalum−niobium mine at lowtemperature environments has always been needed. In this study, we synthesize a new amine-based gemini surfactant, butanediyl-α,ω-bis-(dimethyldodecylammonium bromide) (BDB). It is introduced as a collector in the flotation of lepidolite from the tantalum−niobium mine tailings for the first time at low temperatures. We compare its capability to collect lepidolite with the monomeric surfactant 1-dodecylamine (DA). In bench-scale flotation experiments, the Li 2 O recovery of lepidolite concentrate with 80 g/t BDB was 10.96% and 31.85% higher than that with 160 g/t DA at 298 and 275 K, respectively, which indicated that BDB is a better collector for lepidolite than DA. BDB is a novel and superior collector for disposing of lepidolite tailings ponds.

Research Progress with Scheelite Flotation Reagents: A Review

“…Of note, DDAC is a Gemini-type surfactant that has stronger adsorption on the target mineral surface, more activity and foaming power, a lower Krafft point, and improved foaming performance compared to traditional surfactants containing a single hydrophobic chain and a single polar group. Huang et al found that the novel Geminitype collector butanediyl-α,ω-bis(dimethyldodecylammonium bromide) (BBD) displayed a stronger low-temperature flotation performance than DDA [80]. Ni et al synthesized a new Gemini-type surfactant, hexane-1,6-didodecyldimethylammonium bromide (HDDA), which achieved selective separation of scheelite and calcite in pure mineral experiments without any inhibitors.…”

Prospective Environmental Assessment of Reprocessing and Valorization Alternatives for Sulfidic Copper Tailings

“…For example, one study uses desulfurization flotation techniques to separate sulfur-rich streams (Broadhurst et al, 2015) and generate by-products while simultaneously decreasing acid mine drainage potential. Another study relies on a combined magneticflotation, which can further improve technical performances and extract metals (Huang et al, 2020), and reduce the need for primary mining. If metal contents are high (< 0.5%-wt in copper tailings), other researchers encourage leaching or other separation techniques to maximize metal recoveries (X.…”

Bipyridine-Containing Polysulfide Materials for Broad-Spectrum Removal of Heavy Metals from Water

“…Mining is one of the major causes of metal contamination in water. Advances in the reverse floatation of mine tailings have been shown to alleviate soil and water pollution. − Mercury is the most toxic element among the heavy metals, and the remediation of mercury-contaminated water and soil is very important. − Other heavy-metal pollutants such as zinc, copper, lead, cadmium, chromium, and nickel, commonly found in the wastewater of electroplating, steel smelting, and paint manufacturing industries, are also threats to the environment and health. − Gallium and indium compounds are extensively used in semiconductors. Moreover, the waste generated from gallium and indium compounds from the semiconductor industries is becoming a significant environmental issue due to the increasing demand for these products across the globe. , Methods to remove heavy metals from wastewater include chemical precipitation, ion exchange, adsorption, reverse osmosis, electrodialysis, and ultrafiltration. ,, Adsorption is one of the most effective methods to remove heavy metals since the process is relatively straightforward, low in cost, and highly efficient, whereas other removal techniques may have problems such as the generation of a large amount of sludge and costly disposal.…”