Ion-adsorbed rare earth minerals have rare earth ions adsorbed on the surfaces of clay minerals such as kaolinite and have high contents of medium and heavy rare earth elements. They are important resources supporting the development of high-tech industries. In this study, the CASTEP module in Materials Studio was used to study the adsorption of the rare earth ion Y(III) on the interface of (Al-OH)-H₂O and (Si-O)-H₂O with density functional theory. The monitoring and calculation of the chemical bond of the adsorption structure showed that Y(III) on the (Al-OH)-H₂O interface has a bond with O32, O34, and water molecules in the interface. In the (Si-O)-H₂O interface, Y(III) interacts with O3, O4, and O10 to form new chemical bonds. The Mulliken population and density of states analysis showed that Y(III) bonds with surface oxygen atoms and water molecules in the kaolinite-H₂O interface, and finally adsorbs on the surface of kaolinite in the form of metal ion hydrate.

Montmorillonite is a major mineral present in ion-adsorption rare earth ores, and the microscopic adsorption states of rare earth ions on its surface are of a great significance for the efficient exploitation of ion-adsorption rare earth ores. In this article, density functional theory calculations were used to investigate the adsorption mechanisms and bonding characteristics of hydrated Pr, Mg and NH₄ ions on the (001) surface of montmorillonite. Pr³⁺ exhibited a directed tendency geometry with Pr(H₂O)₁₀³⁺, which was adsorbed onto montmorillonite by hydrogen bonding with an adsorption energy of −1182 kJ/mol, and one coordinated H₂O ligand was separated from the first hydration layer of Pr. Both hydrated Mg and NH₄ ions were adsorbed onto the montmorillonite surface through hydrogen bonds, and the adsorption energies were −206 and −188 kJ/mol, respectively, indicating that the adsorption stability of the hydrated Mg ion was slightly higher than that of the hydrated NH₄ ion, but both were lower than that of hydrated Pr (−1182 kJ/mol). Hence, higher concentrations of Mg and NH₄ ions than rare earth ions would be necessary in the leaching process of ion-adsorption rare earth ores. Additionally, desorption experiments revealed that the recovery of Pr³⁺ by Mg²⁺ with a concentration of 38 mmol/L is 80%, while it is only 65% with the same concentration of NH₄⁺, and the concentrations of Mg²⁺ and NH₄⁺ were much higher than that of Pr³⁺ in lixivium, which is consistent with the DFT calculations.

Separation of chalcopyrite from molybdenite is currently mainly carried out by flotation, but this process is costly because of the extensive use of inhibitors. This study briefly describes a 7.0T/100CGC low-temperature superconducting magnetic separator and discusses its separation principle as well as the effect of magnetic induction on chalcopyrite separation from molybdenite. A molybdenum (Mo) concentrate assaying 6.00% copper (Cu) and 19.01% Mo was magnetically sorted using a diamond-shaped steel rod medium mesh at a feed concentration of 20% and a pulp flow rate of 5 L/min from a Cu-Mo flotation concentrate with 88% of particles smaller than 23 μm using the separator. A Mo concentrate assaying 0.46% Cu and 16.28% Mo was finally obtained with a roughing (1.3 T)-cleaning (5 T) superconducting magnetic separation process. Similarly, the superconducting magnetic separator was performed to separate a Cu-Mo bulk flotation concentrate, and produced Cu concentrate assaying 19.64% Cu and 0.03% Mo from the bulk concentrate assaying 18.52% Cu and 0.39% Mo with a particle size of less than 0.074 mm. At a magnetic induction of 7 T, a pulp concentration of 20% and a feed velocity of 5 L/min, the grade and recovery of Cu in the magnetic product were 19.64% and 81.59%, respectively, whereas the grade and recovery of Mo in the non-magnetic product were 1.52% and 90.07%, respectively. Superconducting magnetic separation has potential applications for removing Cu from Mo concentrates, and separating Cu and Mo from Cu-Mo bulk flotation concentrates.

A significant quantity of tailings is produced during the development of different metal mines in China. In particular, fine-grained tailings pose challenges to the sustainable development of the mining industry. This study examines the utilization of finely ground tungsten tailings as a replacement for natural aggregates in self-leveling mortar (SLM). The study examined the impact of the aggregate-cement ratio, cement mix ratio, and varying substitution levels of different grain sizes of tungsten tailings on the flow properties, mechanical properties, and dimensional change rate of SLM. Additionally, the role of tungsten tailings in SLM was analyzed using XRD, FTIR, and SEM methods. The findings demonstrated that the utilization of sulphoaluminate cement (SAC) had a notable impact on improving the initial strength of the SLM. Additionally, a high aggregate-cement ratio negatively affected the fluidity of the SLM. The doping of tungsten tailings improved the grading relationship of the SLM. Substituting tungsten tailings of 38–75 μm grain size for natural aggregates in the preparation of SLM did not have a negative impact on its performance. In fact, substituting 60% tungsten tailings had a positive effect on the 28-day mechanical properties of the SLM. The compressive and flexural strengths of the SLM after 28 days were 26.53 MPa and 9.06 MPa, respectively, which were enhanced by 18.81% and 26% compared to the control group (C0). According to the environmental leaching test, SLM can effectively fix the heavy metal ions in tungsten tailings, and the leaching concentration of heavy metals is significantly reduced after long-term curing. The doping of finely fragmented tungsten tailings accelerated the process of hydration, resulting in the creation of hydrocalcium zeolite crystals in the latter phases of hydration. Furthermore, an increase in tailings substitution resulted in the production of a greater amount of hydration products, specifically C-S-H gels.

A polyamine special ion exchange resin was used to adsorb Mo from ammonium tungstate solutions. The effects of adsorption time, S²⁻ concentration, adsorption temperature, CO₃²⁻ concentration, mass ratio of WO₃ to Mo, and Mo concentration on the Mo and WO₃ adsorption capacities were investigated. Energy dispersive spectrometer plane scans were used to study the distributions of Mo, W, S, and Na on the loaded polyamine special ion exchange resin and the desorbed polyamine special ion exchange resin. The results showed that the polyamine special ion exchange resin performed well during adsorption and desorption. Under the optimum conditions for the static adsorption experiments, the adsorption capacities for Mo and WO₃ were 99.29 mg/mL and 31.97 mg/mL, respectively, and the desorption rates for Mo and WO₃ were 99.35% and 99.43%, respectively. Adsorption and desorption of molybdenum and tungsten on the polyamine special ion exchange resin were investigated by dynamic adsorption experiments with an ammonium tungstate solution containing 125.0 g/L WO₃, 12.50 g/L Mo, 15.65 g/L S²⁻, and 0 g/L CO₃²⁻. The adsorption capacities for Mo and WO₃ were 53.48 mg/mL and 9.79 mg/mL, and the adsorption rates for Mo and WO₃ were 99.05% and 1.81%, respectively. The loaded polyamine special resin was desorbed with a 45 g/L sodium hydroxide solution, and the dynamic desorption rates for Mo and WO₃ were 99.02% and 99.29%, respectively.