In this work, selective flotation separation of microfine apatite and chlorite was achieved by using sodium oleate (NaOL) as a collector with a low dosage of acidified sodium silicate (ASS) as a depressant. The optimum ratio of sodium silicate to sulfuric acid for ASS was 5:3, and a good separation effect was also achieved in the mixed ore system. Compared to the deionized water system, the ions of Na⁺, Ca²⁺ and Mg²⁺ in seawater adsorbed on the surfaces of apatite and chlorite, which made the zeta potential of the two minerals shift positively. This presented a challenge to the selection of reagents for mineral separation. The addition of ASS changed the pH value of the pulp from weak alkalinity caused by seawater to weak acidity, which allowed the metal ions adsorbed on the mineral surface to desorb. Meanwhile, ASS can selectively adsorb on the desorbed chlorite surface in the form of Si(OH)₄, which hindered the action of NaOL, leading to the depression of chlorite. NaOL adsorbed well on the desorbed surface of apatite and increased the apatite particle size from 27 μm to 229 μm, with a hydrophobic agglomeration effect, thus enhancing the flotation of microfine apatite.

The processing of low-grade, lead-containing practical ores requires fine grinding to liberate galena and enhance flotation recovery. The ball mill is still one of the most common approaches used in industry for fine grinding. This study investigated the effect of the grinding parameters in a ball mill on the fine grinding product of galena and on flotation performance. The grinding product had a particle size below 30 μm, which was classified into +25 μm, −25 + 10 μm, and −10 μm fractions. Grinding experiments showed that modifications to the grinding concentration, media proportion, and filling ratio exerted significant effects on the yields of the +25 μm and −10 μm fractions. Flotation experiments showed that the yield of −10 μm particles negatively affected the flotation performance of galena. Discrete element method simulation results revealed that an increase in the motion velocity of the media group enhanced attrition effects during fine grinding, promoting the generation of −10 μm particles. The higher yield of −10 μm particles facilitated a smaller contact angle and smaller agglomerate size, resulting in lower recovery. To optimize the particle size distribution and improve fine-grained galena flotation recovery, it is essential to reduce the attrition of the grinding media on the mineral.

Owing to differences in the luminous intensity and peak wavelength of each mini-LED, mura has become a key constraint in display applications. To solve this problem, an advanced demura technology of hybrid chip sorting with the advantages of high efficiency and low cost is proposed, and the mini-LED arrays by using the standard and hybrid chip-sorting methods were fabricated. Then, the visualization and evaluation of the aggregation effect of these mini-LED arrays were achieved through simulations. The measured electroluminescence intensity distribution and wavelength distribution both indicate the excellent display effect of mini-LED arrays by using the hybrid chip sorting technique, which provides a reference for replacing the traditional highly complex and high-cost demura technology based on integrated circuit (IC) regulation.

High-intensity conditioning (HIC) is a common pretreatment process for enhancing the flotation of fine-grained minerals. This study introduces fractal theory into the structural design of pulp conditioning impellers. A fractal blade with multi-scale fractal edge features was proposed, and its separation performance was evaluated in a fine-grained malachite (−20 μm) and quartz flotation system. Computational fluid dynamics simulation revealed that the fractal blade altered the energy dissipation pattern. Compared with conventional rectangular blades, it induced stronger fluid compression and collision effects in localized regions. These hydrodynamic changes improved the suspension homogeneity and dispersion efficiency of fine-grained malachite. Furthermore, the fractal blade reduced the scale of turbulent vortices while increasing local turbulent kinetic energy and shear rates. This optimized turbulent flow field effectively reduced mass-transfer resistance and promoted interfacial interactions between flotation reagents and mineral particles. Adsorption experiments and optical microscopy indicated that after conditioning at 1500 rpm for 3 min, the fractal blade increased sodium oleate adsorption on malachite compared to the conventional blade. This enhanced adsorption promoted the aggregation of fine-grained malachite, increasing its aggregate size by 15.52%, while no significant aggregation was observed for quartz particles. Consequently, the single mineral flotation recovery of fine-grained malachite increased by 4.13%. For artificial mixed minerals, the copper concentrate grade and recovery were improved by 2.28% and 1.04%, respectively. This study provides a theoretical basis for equipment optimization and structural innovation design in HIC processes.

Imidazole-based ionic liquids hold immense potential in the field of mineral flotation due to their tunable properties. In this study, three imidazole-based ionic liquids with varying carbon chain lengths (OMB, DMB, and HMB) were selected as collectors for quartz flotation to systematically investigate the microscopic mechanisms by which carbon chain length influences the agglomeration and flotation behavior of quartz. Flotation tests and online particle-bubble monitoring (PBM) results indicate that the elongation of the collector’s carbon chain significantly enhances its collecting ability and reduces the required reagent dosage. To achieve the complete recovery of quartz in a neutral system, a dosage of 35 mg/L is required for OMB, whereas HMB requires only 8 mg/L. As the carbon chain lengthens, the optimal pH range for highly efficient flotation shifts from alkaline to neutral-acidic. Interfacial measurements and mechanistic analyses (Zeta potential and FTIR spectroscopy) confirm that the imidazole ring of the collector physically adsorbs onto the quartz surface through the synergistic action of electrostatic forces and hydrogen bonding, thereby inducing the hydrophobic agglomeration of particles. Notably, in a strongly alkaline system (pH = 11), the long-chain HMB promotes the formation of oversized quartz agglomerates. This leads to a depletion of free reagents in the liquid phase and destabilizes the bubble liquid film, ultimately triggering a sharp decline in recovery. Density functional theory (DFT) calculations further corroborate the structure–activity relationship at the molecular level: the extension of the carbon chain increases the highest occupied molecular orbital (HOMO) energy and electron-donating ability. The adsorption energy of HMB on the quartz (001) surface reached −350.2 kJ/mol, exhibiting the strongest solid–liquid interfacial affinity. This study elucidates the competitive mechanism of carbon chain length in regulating electrostatic adsorption, hydrophobic agglomeration, and froth stability, providing a solid theoretical foundation for the molecular design of novel green flotation reagents for quartz.