In order to develop Xiangshan uranium-rare earth associated ore economically and effectively, a novel strain of Microbacterium sp. 6-1 with specific uranium recognition capability was utilized to conduct the bioleaching experiment on Xiangshan uranium-rare earth associated ore. The results show that a novel strain of Microbacterium sp. 6-1 can be directionally attached to the surface of uranium-containing minerals and efficiently leach uranium elements and associated rare earth resources. Around 81% uranium and 62% rare earth elements can be leached from the uranium-rare earth associated ore within 30 d, with a further enrichment of heavy rare earth elements in the leachate. The research results have important reference significance for the comprehensive development of uranium-rare earth associated mineral resources.

Magnetic mesoporous carbon(MMC) and hydroxyapatite(HAP) composite materials with different mass ratios were prepared by co-precipitation method(MMC@HAP-x x=1, 4, and 6), and used for the removal of radioactive U(Ⅵ) in aqueous solution. The structure, functional groups and surface potential of the MMC, HAP and MMC@HAP-x were characterized by XRD, FT-IR, Zeta. The kinetics, thermodynamics, and the mechanism of MMC@HAP-x adsorption of U(Ⅳ) by the aforementioned materials were systematically studied. The results show that the optimal pH of MMC@HAP-x for U(Ⅵ) is 4.0, and the time required to reach adsorption equilibrium is less than 10 min. The theoretical saturated adsorption capacity of MMC@HAP-6 is 1 164.62 mg/g, and the adsorption process is a spontaneous chemisorption process. The fixation of U(Ⅵ) in MMC@HAP-x is due to the interaction between HAP and $\mathrm{UO}_{2}^{2+}$ to form Ca(UO₂)₂(PO₄)₂·3H₂O. MMC@HAP-6 is a fast uranium adsorbent with the potential to be used for the removal of uranium from radioactive wastewater.

Taking the fluorine-containing wastewater generated by a tungsten smelting enterprise as the research object, aiming at the problem that the defiuorination effect of the existing process can not meet the requirements of the national comprehensive sewage discharge standard, three processes of calcium chloride precipitation method, calcium chloride aluminum salt coagulation precipitation method and ion exchange refsin defluorination method were compared and studied. The results show that it is difficult to ensure the standard discharge of wastewater by using calcium chloride precipitation method alone. Both calcium chloride aluminum salt coagulation precipitation method and resin defluorination method can reduce F^-mass concentration in wastewater from 58.45 mg/L to below 10 mg/L and the discharge standard can be achieved. In contrast, the resin has the best fluoride removal effect and the defluorination rate of 99.64%. It can be used in combination with chemical precipitation as a combination of deep defluoriation process.

In the process of cobalt extraction from Congo (Kinshasa) copper-cobalt polymetallic symbiotic ore, active magnesium oxide was selected to precipitate cobalt in cobalt containing solution and to prepare crude cobalt hydroxide. The kinetics of hydroxide precipitation in solution was discussed. The effects of particle size of magnesium oxide, the amount and method of adding magnesium oxide, reaction time and temperature on precipitation of iron, cobalt and manganese were investigated. The results show that the impurity iron in the simulated cobalt solution can be quickly removed by adding 30% hydrogen peroxide. Active magnesium oxide with particle size less than 45 μm is added to the simulated cobalt containing solution according to the addition amount of 0.68/1 and multiple additions by reaction at room temperature for 6 h, and the obtained primary precipitation can meet the requirements of industry standards for gradeⅠ and secondary precipitation can meet the requirements of gradeⅢ. The process has the advantages of low cost and high practicability, and can effectively improve the efficiency of magnesium oxide cobalt deposition.

The electric submersible pump (ESP) is the main equipment for the in-situ leaching uranium industry in China, effectively increasing the production of leaching fluid. However, few studies on the internal flow field subject to rotating-stationary-parts interactions are available in literature. With the internal structure of impeller-guide vane as the research object, CFD method was applied to carry out unsteady analysis on the flow characteristics of the medium, and the variation mechanism of pressure pulsation inside the impeller and the outlet section of the impeller was studied. Moreover, the transient flow field data were used to analyze the pressure flow field in the section of the impeller through the action mode decomposition (DMD) and pressure flow field reconstruction. The periodic variation mechanism of pressure pulsation caused by static and dynamic interference and the influence of distance between static and dynamic components on the intensity of static and dynamic interference are revealed. The results indicate that the frequency values of the blades are basically consistent with those of the Fast Fourier Transform (FFT). These findings offer valuable theoretical underpinnings for mitigating undesirable pump vibrations induced by pressure pulsations, optimizing ESP hydraulic component parameters, and ultimately improving system efficiency.

Aiming at leaching solution of indium residue produced by zinc hydrometallurgy, rotating disk extraction tower was used to separate indium and iron from the solution. The extraction effects of indium and iron ions in the solution, the extraction sequence of metal ions, the separation effect and emulsification of light and heavy phases was studied. The influences of the rotating disk rotating speed, feed flow rate, concentration of P204, solution acidity, reaction temperature and the phase ratio on separation effects were examined. The results show that under the optimal conditions of reaction temperature of 25 ℃, heavy phase volume flow rate of 7.8 L/h, P204 concentration of 20%, rotating disk rotating speed of 360 r/min, initial acidity of 60 g/L, V_O/V_A phase ratio of 1/1, the extraction rate of indium can reach 75%, the extraction rate of impurity element iron is less than 5%. The light and heavy phases are basically completely separated, and there is no emulsification. The result of extraction isotherms shows that complete extraction of indium can be achieved by three-stage countercurrent extraction under the condition of V_O/V_A phase ratio of 1/1. The loaded organic phase is pre-washed with dilute sulfuric acid, and then stripping with 5 mol/L hydrochloric acid under the condition of V_O/V_A=1/1. And the extraction rate of indium is more than 98%. After the replacement treatment, the stripping solution can be directly returned to zinc hydrometallurgy, the organic phase can be recycled after scrubbing.

The harmless treatment and resource utilization of spent cathode carbon from the overhaul slag of aluminum electrolytic cells is the bottleneck for achieving green and sustainable development in the electrolytic aluminum industry. The migration patterns of toxic components and toxic elements in spent cathode carbon for aluminum electrolysis are introduced. The technical principle, research status, advantages and disadvantages of high temperature fire method, liquid-phase leaching method and collaborative treatment method are summarized, and the future development trend is prospected.

The mineral composition and valence state composition of vanadium clinker in vanadium slag and salt-free roasting stage at different temperature nodes were studied by photoelectron spectroscopy and mineral analyzer. The results show that the contents of vanadium spinel, ferroolivine and calciferite decrease with the increase of roasting temperature, while the contents of iron oxide, ferrotitanite and manganese vanadate increase with the increase of roasting temperature. With the increase of roasting temperature, the oxidation of vanadium slag from V³⁺ to V⁴⁺ is gradually transformed into the internal oxidation of V³⁺ to V⁴⁺ and V⁴⁺ to V⁵⁺. The valence state of vanadium in vanadium spinel is V³⁺ and the valence state of vanadium in oxidation state is V⁴⁺. The mineral analysis results of vanadium slag and clinker are in good agreement with the valence analysis results of vanadium element.

Aiming at the difficulty of extracting and separating of high purity single rare earth elements or compounds, a new emulsion liquid film was constructed and used for the extraction and separation of Re(Ⅲ) (La³⁺, Ce³⁺, Pr³⁺, Nd³⁺). The types and concentrations of mobile carriers and surfactants, and the internal water phase in liquid film system were determined by single factor experiment. The results show that the optimal composition of the emulsion liquid membrane system is 6%D2EHPA, 5%T154, 3 mol/L HCl solution, phase ratio R_oi=1.5. The emulsion film constructed in this system has stable phase and excellent extraction effect, and can realize efficient separation of Re(Ⅲ).

A gold grade prediction model was proposed by combining improved cloud models with improved RBF neural networks. Qualitative information was quantified using DS evidence theory and cloud models, and then quantum particle swarm optimization algorithm and RBF neural network were used to predict the gold grade in ores. The results indicate that the mean square error of this model is 0.009 2, the maximum error is 0.016 1, and the correlation coefficient is 0.940 2, the model can better preserve the qualitative information characteristics, the prediction effect of gold grade is good.