The recovery of valuable components from waste ternary lithium batteries and the regeneration of electrode materials were systematically studied. The recovery of valuable components such as Ni, Co, Mn and Li was carried out by using the route of acid leaching—impurity removal—co-precipitation—high temperature solid phase synthesis. The effects of H₂SO₄ concentration and H₂O₂ adding dosage on acid leaching were investigated. The pH of the leaching solution was adjusted by NaOH to remove Fe²⁺ and Al³⁺ impurities, and then the cathode material precursor of ternary lithium battery was synthesized and the active material of the precursor was regenerated, and the electrochemical properties of the regenerated cathode material were discussed. The results show that the leaching rates of Ni²⁺, Co²⁺, Mn²⁺ and Li⁺are 99.7%, 99.1%, 97.2% and 99.5%, respectively, using 0.3 mol/L H₂SO₄ and 8%H₂O₂ as acid leaching agents. Under the condition of pH=4.5~6.5, it can completely precipitate and remove impurities such as Fe²⁺ and Al³⁺, and Ni²⁺, Co²⁺ and Mn²⁺ can be completely precipitated to obtain precursors as the pH rises to 10.0. The cathode material can be regenerated by adding lithium source. The electrochemical performance test results show that at 1 C current density, the specific capacity of ternary lithium battery can reach 143.7 mAh/g for 1 discharge cycle. The performance is stable after 100 cycles, and the CV curve has obvious redox peaks, and the cyclic discharge performance is good at different rates.

Leaching solution with a mass concentration of 256.1 mg/L was obtained by using aqua regia to recover the gold from the CPU, and the gold in the acid leaching solution was recovered by solvent extraction. The effects of extractant type, concentration, extraction time, extraction phase ratio and extraction temperature on the gold extraction were investigated. The results show that with 80% dibutylcarbitol as the extraction agent, the gold extraction rate can reach 99.86% under the condition of V_O∶V_A=1∶4 and room temperature for 10 min. The sponge gold product can be obtained by stripping with oxalic acid. The recovery effect is good. The method has a certain popularization value in the comprehensive recovery of gold-containing electronic solid waste such as CPU.

The perchlorinated zinc ash contains zinc metal, a small amount of heavy metals and harmful elements chlorine. In order to reduce the chlorine content in the perchlorinated zinc ash, the removal effect of water washing and ammonia washing on the impurities in the perchlorinated zinc ash was compared and studied. The influence of ammonia concentration, liquid volume to solid mass ratio and washing temperature on the precipitation rate of zinc in the ammonia washing process was investigated by single factor test, and the optimal ammonia washing conditions were determined by orthogonal test. The results show that the removal rates of Cl, Na and K are more than 99% and the precipitation rate of Zn is 98.7% under the conditions of ammonia concentration of 0.05%, liquid volume to solid mass ratio of 6 mg/1 L and reaction temperature of 30 ℃.

Electrolysis of Manganese using Ionic liquid choline chloride as additive instead of selenium dioxide, under simulated industrial electrolytic conditions was studied. The electrolytic products were characterized by SEM and XRD, and the electrochemical mechanism of the cathode was analyzed by cyclic voltammetry(CV) and cathode polarization curve(LSV). The results show that the electrolytic product with ionic liquid choline chloride as additive has smooth, dense surface, and has a metallic luster. The addition of choline chloride can promote manganese deposition and inhibit hydrogen evolution. Under simulated industrial electrolysis conditions, the current efficiency is up to 68.1%.

The efficient removal of fluoride from zinc smelting waste acid by complex extraction using P204 as the extractant was investigated. The effects of concentration of fluorine and aluminum in aqueous phase, pH, extraction temperature and time on the extraction rate of fluorine and aluminum were examined, The resource utilization of aluminum fluoride was also discussed. The results show that under P204 concentration of 1 mol/L, Al³⁺ concentration in aqueous phase of 0.1 mol/L, F^- concentration of less than 0.025 mol/L, pH=3.0~3.5, extaction time of 8 min and room temperature, the extraction rate of fluorine can reach 96.18%. Using 1.0 mol/L sulfuric acid solution to strip of the fluorine-aluminum-loaded organic phase, the stripping rates for F^- and Al³⁺ are 81.88% and 39.39%, respectively. Cryolite can be obtained by precipitation of stripping solution, and the synthesis of cryolite is more favorable under the condition of pH=4.

The extraction performance of gallium in sulfuric acid solution with new alkyl hydroxamic acid DX201 and P204 was studied. The effects of extraction and stripping conditions on gallium extraction performance were investigated. The extraction and stripping isotherms were drawn. The results show that the single-stage extraction rate of gallium is 97.52% under the conditions of V_O/V_A=1/1, extraction temperature of 25 ℃ and extraction time of 15 min in sulfate solution with mass concentration of sulfuric acid of 20 g/L sulfate solution and organic phase composition of 10%DX201+15%P204+75%260^#solvent oil. Using 2.5 mol/L dilute sulfuric acid solution to strip gallium from supported organic phase, the single stage stripping rate of gallium is 94.21% under the conditions of V_O/V_A=2/1, stripping temperature of 25 ℃ and stripping time of 2 min. The extraction rate of gallium in 3-stage countercurrent extraction is 99.64%, and the extraction performance is stable.

In order to comprehensively recover the valuable components from decommitted high-nickel ternary lithium batteries,lithium was selectively extracted by sulphation roasting and water leaching, and the water leaching residue was then processed by aging leaching,impurity removal and coprecipitation to prepare nickel-cobalt-manganese hydroxide. The results show that the optimum conditions of sulfation roasting are n(H₂SO₄)∶n(Li)=1.4∶1, roasting temperature of 600 ℃, roasting time of 1 h, and the water leaching rate of Li, Mn can reach 94.36%, 11.03%, respectively, Ni and Co hardly leaching. Under the conditions of acid-ore ratio of 1.74, curing temperature of 120 ℃, curing time of 120 min and liquid volume to solid mass ratio of 7.5 mL/1 g, the aqueous leaching slag is cured and acid leaching. The leaching rates of Li, Ni, Co, Mn, Cu, Fe and Al are 97.86%, 89.16%, 95.09%, 100%, 63.6%, 99.71% and 56.76%, respectively. Under the optimum conditions of pH=3.38, precipitation temperature of 60 ℃ and precipitation time of 60 min, the precipitation rates of Fe, Al and Cu in the solution can reach 100%, 98.07% and 82.51%, respectively. Nickel cobalt manganese hydroxide can be formed by co-precipitation after pH adjustment. Under the optimal conditions of pH=9.44, co-precipitation temperature of 55 ℃ and co-precipitation time of 120 min, the precipitation rates of Ni, Co and Mn can reach 99.6%, 100% and 98.72%, respectively.

An economic benefit optimization model for hydrometallurgical equipment control was established, and an optimization algorithm based on Double Deep Deterministic Q-Network (DDQN) model is introduced. At the same time, Residual Network is combined with residual network. ResNet's deep learning capability to realize the detection and early warning of abnormal equipment operation status. The simulation results show that the intelligent control algorithm can not only greatly improve the operating efficiency of hydrometallurgical equipment, but also enhance the stability and reliability of the system and improve the economic benefit of enterprises.

In order to improve the electrochemical performance of stannous sulfide(SnS) anode material for lithium batteries, SNSS/DA precursor was prepared by one-step hydrothermal method with niobium cation and selenium anion doped SnS, and then SNSS/C composite was prepared by heat treatment. The effects of carbon nanolayer and co-doping mechanism on the conductivity and battery cycle stability of SNSS/C composite were investigated. The results show that SNSS/C composites have good coating morphology and carbon coating structure, and the thickness of carbon nanolayer is 10~30 nm. By doping two elements, Nb and Se, the crystal volume can be increased, so that lithium ions can obtain a broader channel in the process of embedding/deembedding, and further enhance the conductivity of the material and the diffusion efficiency of lithium ions. The electrochemical performance of SNSS/C material is excellent, the specific discharge capacity of the first cycle is 814.6 mAh/g, and the Coulomb efficiency is 96.3%.

In order to develop a high efficiency, environmental protection, low energy consumption of heavy metal Cr (Ⅵ) adsorbent magnetic biochar (MBC) was obtained by co-precipitation reaction in a mixture of FeSO₄·7H₂O and FeCl₃·6H₂O with alkali modified biochar as the substrate. polyethyleneimine(PEI) was then used as an amination agent and glutaraldehyde was as a cross-linking agent to produce PEI-functionalized magnetic biochar composites(PEI/MBC) for Cr(Ⅵ) removal, PEI/MBC was characterized by SEM,XRD and FT-IR. The effects of solution pH, adsorbent dosage and competitive ions on the adsorption properties for Cr(Ⅵ) were investigated,the results show that the highest adsorption amount of 105.94 mg/g is achieved under the conditions of initial Cr(Ⅵ) concentration of 50 mg/L, an adsorbent dosage of 0.2 g/L, temperature of 30 ℃ and pH=2. The adsorption was affected by the changes of competitive anions and temperature, the quasi-second-order kinetic equation can well reflect the adsorption behavior of Cr(Ⅵ) on PEI/MBC, and the isothermal adsorption data is consistent with the Freundlich isothermal adsorption model, the adsorption of Cr(Ⅵ) is a spontaneous endothermic process, with ΔG<0, ΔS=144.82 J/(mol·K) and ΔH=39.84 kJ/mol.