A chemical-microorganism synergistically driven microbial combination and leaching method of uranium and polymetallic resources

Abstract

The present application relates to a kind of chemical-microorganism synergistic driving uranium and multi-metal resource leaching microbial combination and leaching method.A kind of microbial combination for uranium and multi-metal resource leaching, including acid-producing-complexing microorganism, surfactant producing bacteria, specific uranium recognition bacteria and redox regulation microorganism, its volume ratio is (1-10):(1-5):(1-10):(1-10).A kind of uranium and multi-metal resource leaching method, utilizes chemical oxidation and above-mentioned microbial combination and cooperatively drives uranium and multi-metal resource leaching.The present application is combined by low-dose chemical oxidation trigger system and multifunctional microbial combination leaching system, constructs an efficient chemical-microorganism synergistic oxidation leaching regulation system, and is suitable for solving complex, difficult to handle co-associated uranium ore in multiple metal occurrence state, mineral interface reaction is slow, difficult to cooperatively dissolve technical bottleneck.

Description

Technical Field

[0001] This invention belongs to the field of comprehensive utilization technology of mineral resources, and in particular relates to a chemical-microbial synergistic driven method for the microbial combination and leaching of uranium and polymetallic resources. Background Technology

[0002] With the continuous development of the nuclear energy industry, the demand for uranium resources is constantly increasing. High-grade uranium ore is gradually decreasing, making low-grade ore and complex associated minerals important resource sources. Traditional hydrometallurgical processes for uranium ore typically employ chemical processes such as acid or alkaline leaching, supplemented by oxidants to convert tetravalent uranium to hexavalent uranium. Although these technologies are mature, they generally suffer from high acid or alkaline consumption, large oxidant usage, highly corrosive leaching systems, and complex tailings treatment, especially prominent in the development of low-grade uranium ore or uranium-polymetallic associated mineral resources. Furthermore, the use of high-strength chemical reagents may increase environmental remediation costs and have potential impacts on the ecological environment of mining areas.

[0003] In recent years, microbial leaching technology has gradually become an important supplementary means of mineral resource development. Some microorganisms can produce metabolic products such as organic acids, metal complexing agents, and surfactants through their metabolic activities, thereby promoting the destruction of mineral crystal structures, enhancing the surface reactivity of minerals, and promoting the dissolution and migration of metal ions. Therefore, microbial leaching is considered a green metallurgical technology with potential for environmental friendliness and resource utilization efficiency. However, existing bioleaching systems still face several technical bottlenecks in practical applications. First, the oxidation capacity of microbial systems is usually relatively limited. Most heterotrophic or neutral-environment microorganisms cannot directly oxidize U(IV) and need to rely on iron oxidation cycles or other indirect oxidation processes, resulting in a long induction period in the uranium ore leaching process, thus affecting the overall leaching efficiency. Second, in uranium-multimetal coexistence systems, high concentrations of metal ions often inhibit microbial metabolism. Associated metal ions such as copper, nickel, cobalt, and rare earth elements may interfere with the microbial cell membrane structure or enzyme activity, thereby reducing the microbial growth rate and metabolic activity, further affecting the stable operation of the leaching system. In addition, the regulation of redox conditions in microbial systems is also quite complex. The redox environment generated by microbial metabolism is often affected by multiple factors such as dissolved oxygen, electron donors, metabolic byproducts, and mineral surface reactions. It is difficult to maintain the optimal redox potential range that is conducive to uranium oxidation and dissolution for a long time, thus limiting the continuous improvement of leaching efficiency.

[0004] Chemical-biological synergistic leaching appears to be a feasible solution to the aforementioned contradictions. However, conventional chemical reagents are highly toxic, and oxidants easily cause oxidative damage to microbial cells, leading to microbial inactivation and making it difficult to form a stable synergistic effect with the bioleaching system. Currently, chemical-biological synergistic leaching processes have not yet been established in uranium ore leaching.

[0005] Therefore, in the process of uranium-polymetallic resource development, how to construct a synergistic leaching system that can take into account both chemical oxidation efficiency and microbial metabolic stability, and achieve efficient oxidation and leaching of uranium and associated metals in minerals while maintaining microbial activity, has become an important technical problem that urgently needs to be solved in the field of green development of uranium resources and biometallurgy. Summary of the Invention

[0006] In view of this, the present invention provides a chemical-microbial synergistic-driven microbial combination and leaching method for uranium and polymetallic resources. By constructing a low-dose chemical oxidation triggering system and a multifunctional microbial combination system, a stable chemical-biological coupling reaction environment is formed at the mineral interface, thereby significantly improving the leaching efficiency of uranium and its associated metal resources.

[0007] This invention provides a microbial ensemble for uranium and polymetallic resource leaching, comprising acid-producing-complexing microorganisms, surfactant-producing bacteria, specific uranium-recognizing bacteria, and redox-regulating microorganisms. The volume ratio of the acid-producing-complexing microorganisms, the surfactant-producing bacteria, the specific uranium-recognizing bacteria, and the redox-regulating microorganisms is (1-10):(1-5):(1-10):(1-10), with a lower limit of 1 for each value, preferably 3:2:5:5.

[0008] Preferably, the acid-producing complexing microorganism is one or more of the following: *Arthrobacter*, *Amycosis*, *Cladosporium*, *Morchella*, *Penicillium*, *Syntrophus*, *Pandora*, and *Massezia*.

[0009] Preferably, the surfactant-producing bacteria are one or more of the following: Trichomonas vaginalis, Agrobacterium, Sphingosine monocytogenes, Oligotrophoblastus, Rifonsonia, and Mycobacterium.

[0010] Preferably, the specific uranium-recognizing bacterium is BrickRed Microbacterium XS6-1.

[0011] Preferably, the redox-regulating microorganism is one or more of the following: Thiobacillus, Leptospira, Fertilobacterium, Acidobacterium, and Bacillus sulfide.

[0012] The present invention also provides a leaching method for uranium and polymetallic resources, which utilizes chemical oxidation and any of the above-mentioned microbial combinations to synergistically drive the leaching of uranium and polymetallic resources.

[0013] Preferably, the leaching method includes the following steps: Step 1: Crush the ore containing uranium and associated metals to a particle size of 0.5-10 mm; Step 2: Chemically oxidize the ore for 0.5-4 hours; Step 3: Add the bacterial solution containing the microbial combination to the reaction system. First, add the acid-producing-complexing microorganisms and mix them evenly with the ore. After reacting for 1-4 hours, add the surfactant-producing bacteria. After reacting for another 0.5-3 hours, add the specific uranium recognition bacteria and the redox-regulating microorganisms. The volume ratio of the acid-producing-complexing microorganisms, the surfactant-producing bacteria, the specific uranium recognition bacteria, and the redox-regulating microorganisms is (1-10):(1-5):(1-10):(1-10), and the lower limit of each value is 1. Step 4: Maintain the pH of the system at 1.0-8.0 and the temperature at 10-60℃ to carry out the leaching reaction, with a cycle of 2-10 days.

[0014] Preferably, the chemical oxidation process includes the addition of an oxidant and a stabilizer. The oxidant includes one or more of hydrogen peroxide, percarbonate, and persulfate, preferably hydrogen peroxide. The stabilizer includes one or more of organic acids, organic acid salts, aminocarboxylic acids, aminocarboxylic acids, phosphonic acids, phosphonates, phosphoric acid, phosphates, polyphosphoric acid, polyphosphates, humic acid, humates, fulvic acid, and fulvicates.

[0015] Preferably, the total concentration of the oxidant is 0.0001%-0.01% of the mass of the ore, more preferably 0.001%; ​​the total concentration of the stabilizer is 0.000005%-0.005% of the mass of the ore, more preferably 0.0002%.

[0016] The beneficial effects of this invention include: This invention achieves highly efficient synergistic leaching of uranium and associated metals through a sequential synergistic process of "low-dose stabilization-Fenton-like pre-triggering - oxidant decay - directional attachment of specific uranium-recognizing bacteria - continuous metabolic amplification of multifunctional microbial communities". The low-dose oxidant-stabilizer system rapidly activates the mineral surface and increases Eh in the early stages of leaching, but before microbial inoculation, the oxidant (e.g., H2O2) decays to a level that does not significantly inhibit cell activity. Subsequently, acid-producing-complexing microorganisms and surfactant-producing bacteria respectively enhance lattice erosion and interfacial mass transfer. Specific uranium-recognizing bacteria specifically accumulate on the uranium mineral surface, preferentially promoting directional uranium mineral leaching. Redox-regulated microorganisms maintain Fe... 2+ / Fe 3+ Cyclic and local Eh window. The above process creates an irreplaceable synergistic relationship between the rapid triggering effect of chemical oxidation and the continuous, targeted, low-load leaching effect of microorganisms.

[0017] This invention combines a low-dose chemical oxidation triggering system with a multifunctional microbial leaching system to construct a highly efficient chemical-microbial synergistic redox regulation system. This system is suitable for addressing the technical bottlenecks of diverse metal occurrence states, slow mineral interface reactions, and difficulties in synergistic leaching in complex associated uranium deposits. Compared to single chemical leaching, single biological leaching, or simple chemical-biological leaching superposition methods, this invention achieves rapid activation of the mineral interface, metal valence state transformation, and subsequent continuous leaching through the rapid triggering effect of low-dose chemical oxidation combined with the continuous action of microorganisms.

[0018] The combined leaching system of the present invention includes a low-dose chemical oxidation triggering system and a multifunctional microbial combined leaching system.

[0019] The low-dose chemical oxidation triggering system is used to rapidly increase the redox potential (Eh) of the system in the early stage of leaching, promoting the initial transformation of U(IV) on the mineral surface to U(VI) and other low-valence metals to high-valence soluble forms, and gently oxidizing and destroying the mineral surface structure, thereby creating favorable conditions for subsequent microbial attachment, metabolism, and continuous leaching. The oxidation triggering system includes an oxidant (using hydrogen peroxide H₂O₂ as an example) and a stabilizer (using citric acid as an example). A trace amount of exogenous citric acid stabilizer acidifies and complexes the mineral structure iron, which reacts with solid-phase U(IV) to generate chelated Fe. 2+ In the presence of trace amounts of H₂O₂, a mild Fenton-like reaction system is formed, generating reactive oxygen species (such as hydroxyl radicals •OH) with strong oxidizing capabilities. Under controlled conditions, these reactive oxygen species can cause oxidative damage to the mineral surface and crystal structure, thereby promoting the loosening of the mineral structure and accelerating the dissolution process of uranium and its associated metals. Simultaneously, Fe… 2+ It is oxidized to form Fe in a Fenton-like reaction. 3+ As an indirect oxidant, it participates in the electron transfer reaction at the mineral interface, through Fe 2+ / Fe 3+ The cycle further promotes the oxidative release of uranium and associated metals in the mineral lattice. This process effectively increases the redox potential of the solution in the early stages of the system. Within 0.5-4 hours of oxidation treatment, the system Eh significantly increases to 300-650 mV, effectively promoting the initial conversion of U(IV) to U(VI) and enhancing the kinetics of mineral structure destruction and metal dissolution, thus providing a favorable reaction environment for subsequent bioleaching. The stabilizer complexes Fe... 2+ / Fe 3+ Inhibits iron ion hydrolysis and precipitation, maintains Fe 2+ / Fe 3+This process enhances the sustained activation capacity of the low-dose Fenton-like system at the uranium-polymetallic mineral interface. Furthermore, the stabilizer can delay the non-selective decomposition of H2O2 in the slurry system, allowing the low-dose H2O2 to maintain its oxidizing capacity during the pre-oxidation stage.

[0020] In multifunctional microbial leaching systems, acid-producing and complexing microorganisms secrete organic acids (oxalic acid, citric acid, gluconic acid, succinic acid, malic acid, etc.), metal complexing ligands, extracellular enzymes, and extracellular polymers to promote mineral lattice loosening, interfacial erosion, and the complexation and release of metal ions. Surfactant-producing bacteria secrete surfactants (rhamnolipids, trehaloses, sophorol, etc.) and other metabolites that improve ore wettability and interfacial mass transfer conditions, reducing interfacial tension, increasing leaching agent penetration, and enhancing ore-solution contact efficiency. Uranium recognition-preferred leaching microorganisms, specifically *Microbacterium rubrum* XS6-1, specifically recognize and preferentially attach to the surface or surrounding areas of uranium minerals, promoting directional oxidation and continuous leaching of uranium minerals and associated minerals. Redox-regulating microorganisms participate in Fe... 2+ / Fe 3+ Cyclic processes, interfacial electron transfer, and local redox environment regulation specifically refer to the reduction of U(IV) to generate Fe. 2+ Partially oxidized to Fe 3+ (Another part of Fe) 2+ Fe can be implemented through the Fenton class. 2+ / Fe 3+ (Circulation) to maintain the system in a reaction state that is conducive to the release of uranium and associated metals.

[0021] The co-leaching method of this invention is based on the mechanism of chemical oxidation triggering and microbial synergistic leaching. A low-dose, mild oxidant is introduced as a synergistic oxidation trigger source into a multifunctional microbial combined leaching system. By regulating the redox potential (Eh) and pH, the synergistic enhancement of the chemical oxidation process and the microbial metabolic process is achieved. Its technical effects are as follows: 1. Significantly improves oxidation rate: By introducing a low dose of mild oxidant, the system Eh is rapidly increased. Within 0.5-4 hours of oxidation treatment, the system Eh is significantly increased to 300-650mV, accelerating the initial transformation of U(IV) to U(VI) on the mineral surface and promoting the transformation of other associated metals from relatively stable forms to leaching forms, thereby significantly improving the early oxidation reaction rate of the system.

[0022] 2. Enhanced mineral interface activation: The chemical oxidation triggering system can produce a mild oxidative damage effect on the surface structure of minerals in the early stage of leaching, promoting the loosening of mineral lattice, exposure of active sites and unsealing of metal-bearing phases; at the same time, the organic acids, complexing agents and surfactants produced by microbial metabolism further enhance the interface erosion and mass transfer efficiency, thus forming a synergistic strengthening effect of chemical oxidation and bioleaching interface.

[0023] 3. Shorten the leaching cycle: Chemical oxidation triggering can effectively shorten the problem of slow start-up and long induction period of traditional pure biological leaching system, reducing the conventional uranium-polymetallic ore biological leaching cycle from more than 30 days to less than 10 days.

[0024] 4. Reduced Chemical Reagent Usage: This invention employs a low-dose, mildly triggered oxidation strategy. Compared to traditional strong oxidizing chemical leaching systems, it can improve leaching efficiency while reducing the amount of oxidants and strong acids used, thereby lowering reagent costs and environmental risks. Oxidant usage is reduced by more than 90% compared to conventional chemical leaching, and acid consumption is reduced by 100%. Only trace amounts of stabilizers are added during the chemical oxidation process, saving on iron salt input and improving the continuous activation ability of the uranium-polymetallic mineral interface.

[0025] 5. Improved tailings quality: Compared with the traditional strong acid-strong oxidant process, this invention achieves target metal leaching through low-dose chemical oxidation and the synergistic effect of microorganisms, which helps to reduce the acidity and salt load of the system and reduce the pressure of tailings post-treatment.

[0026] 6. Enhanced system stability and controllability: Through the synergistic effect of acid-producing-complexing microorganisms, surfactant-producing bacteria, specific uranium recognition bacteria, and redox-regulating microorganisms, the reaction process is more stable and controllable compared to single-strain leaching systems, and has good potential for process scale-up.

[0027] 7. Improve the efficiency of multi-metal synergistic leaching: This invention can not only promote the oxidative leaching of uranium, but also facilitate the synchronous release and synergistic leaching of associated metals such as copper, cobalt, molybdenum, vanadium, nickel, zinc, lead, germanium, tellurium, selenium, and rare earth elements, thereby improving the comprehensive recovery efficiency of complex associated resources.

[0028] 8. Applicable to the development of complex ores and low-grade resources: This invention can improve the release efficiency of target metals in complex ores, difficult-to-leach ores and low-grade resources, and expand the application scope of chemical-microbial synergistic leaching technology in the development of complex strategic mineral resources. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 The leaching kinetics (rates) of U-Mo polymetallic ores are shown. Left: uranium leaching kinetics; Right: molybdenum leaching kinetics.

[0031] Figure 2 This image shows the distribution of *Microbacterium rubrum* XS6-1 on different mineral particle surfaces and its elemental scanning electron microscopy (SEM) images. A: Secondary electron imaging of *Microbacterium rubrum* XS6-1 specifically adsorbed on the surface of uranium minerals; B: Backscattered image corresponding to image A; C: Elemental scanning electron microscopy (Si); D: Elemental scanning electron microscopy (U). Detailed Implementation

[0032] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Unless otherwise specified, the experimental materials used in the following embodiments can be obtained commercially.

[0033] Existing technologies for uranium ore chemical leaching, pure biological leaching, and simple chemical-biological superimposed leaching have some shortcomings, mainly including the following aspects: (1) The problem of high cost and heavy environmental burden of strong acid-strong oxidant system: Traditional chemical leaching relies on high concentration of acid (10-100kg H2SO4 / t ore, mass ratio 1%-10%) and strong oxidant (1-5kg H2O2 / t ore, mass ratio 0.1%-0.5%), resulting in high acid consumption, serious equipment corrosion, high tail liquid salinity, increased post-treatment difficulty, and high environmental treatment cost.

[0034] (2) Problems of insufficient oxidation capacity and long induction period of pure biological leaching: Microorganisms have limited direct oxidation capacity for U(IV), slow electron transfer rate, and the system often has a long induction period, resulting in a long overall leaching cycle (>30 days, some reports>120 days), which limits the efficiency of industrial application.

[0035] (3) Problem of low synergistic leaching efficiency in complex multimetal systems: In associated minerals such as U-Mo, U-Cu, U-Co, and U-REE, the redox potential, complexation behavior, and leaching conditions of different metals vary greatly, and it is difficult to achieve efficient synergistic leaching of multiple metals in the same system using a single technology.

[0036] (4) Problems of passivation and limited mass transfer at the ore interface: Calcium / iron salt precipitation layer, passivation layer or biofilm residue layer are easily formed on the ore surface, which hinders the leaching agent from penetrating into the deep mineral layer, resulting in a significant decrease in the reaction rate in the later stage.

[0037] This invention proposes a microbial ensemble for uranium and polymetallic resource leaching, comprising acid-producing-complexing microorganisms, surfactant-producing bacteria, specific uranium-recognizing bacteria, and redox-regulating microorganisms. The mass ratio of the acid-producing-complexing microorganisms, surfactant-producing bacteria, specific uranium-recognizing bacteria, and redox-regulating microorganisms is (1-10):(1-5):(1-10):(1-10), with a lower limit of 1 for each value, preferably 3:2:5:5.

[0038] The above-mentioned multifunctional microbial leaching system is composed of microorganisms with different metabolic functions. Different types of microorganisms form a synergistic metabolic network at the mineral interface, and promote the continuous leaching of uranium and its associated metal resources through multiple functions such as mineral interface modification, interface mass transfer enhancement, metal recognition and oxidation, and redox regulation.

[0039] Acid-producing and complexing microorganisms can alter the physicochemical properties of mineral surfaces through metabolism, thereby promoting mineral structure destruction and increasing metal release efficiency. Their mechanisms include, but are not limited to: (a) Organic acid secretion: Microbial metabolism produces low-molecular-weight organic acids such as oxalic acid, citric acid, gluconic acid, and succinic acid, thereby lowering the local pH and promoting mineral lattice structure destruction. (b) Metal complexation and dissolution: Microbial metabolites can complex with U(VI) and Cu... 2+ Co 2+ Ni 2+ (c) Mineral lattice erosion: Extracellular enzymes and metabolites secreted by microorganisms can alter the surface structure of minerals, causing microcracks in the mineral lattice and increasing the reaction interface area. (d) Bioweathering: Microorganisms alter the microenvironment of the mineral interface through metabolic activities, promoting long-term dissolution and structural loosening of minerals. Furthermore, the biofilm formed by the acid-producing-complexing microorganisms selected in this invention is rich in polysaccharides, effectively buffering environmental toxicity under extreme conditions such as strong acid, strong alkali, and heavy metal contamination, constructing a microenvironment conducive to the survival and leaching of subsequent functional microorganisms. Because they play a leading regulatory role in the system, acid-producing-complexing microorganisms should be preferentially added after low-dose chemical oxidation triggering to create suitable leaching conditions.

[0040] Surfactant-producing bacteria can improve the interfacial mass transfer conditions between ore particles and leachate, enhancing the diffusion capacity of the leachate in mineral pores. Their mechanisms of action include, but are not limited to: (a) Biosurfactant action: Microbial metabolism produces rhamnose lipids, trehalose lipids, or other biosurfactant substances, reducing the interfacial tension of the mineral. (b) Extracellular polymeric action: Microorganisms produce extracellular polysaccharides or proteins, forming a stable microbial membrane structure and improving the wettability of mineral particles. (c) Mineral pore permeation: Microbial metabolites can improve the permeability of the leachate in mineral fissures. (d) Mineral surface deposit stripping: Microbial metabolic activities can destroy the deposit or passivation layer formed on the mineral surface, thereby continuously exposing new reaction interfaces. Furthermore, the biofilm of the surfactant-producing bacteria selected in this invention has a high enrichment of type C cytochromes, low intracellular resistance, and strong extracellular electron uptake capacity, thus more effectively promoting the diffusion of U(IV) and Fe. 2+ This process also involves the oxidation of sulfides and improves bioleaching efficiency. Furthermore, these microorganisms can synergistically interact with subsequent specific uranium-recognizing bacteria to further enhance the system's leaching capacity.

[0041] Uranium-specific recognition bacteria can form a stable adhesion layer on mineral surfaces and selectively recognize specific metal minerals, thereby improving metal leaching efficiency. Their mechanisms of action include: (a) mineral-directed adhesion: these microorganisms preferentially adhere to uranium mineral surfaces to form a microbial adhesion layer. (b) local metabolic enhancement: forming highly metabolically active zones on mineral surfaces, increasing the reaction rate at the mineral interface. (c) uranium mineral recognition: achieving targeted mineral enrichment through specific interactions between cell surface functional groups and uranium minerals. (d) uranium oxidation promotion: promoting the conversion of U(IV) to U(VI) through metabolic activity, thus increasing the leaching rate.

[0042] Redox-regulating microorganisms maintain stable redox conditions in leaching systems and participate in metal cycling and electron transfer processes. Their mechanisms include promoting electron exchange at the mineral interface through extracellular electron transfer, participating in the redox cycles of metal ions such as U and Fe, thereby maintaining a stable system Eh (300-650 mV). For example, Fe generated by the reduction of U(IV) 2+ Partially oxidized to Fe 3+ (Another part of Fe) 2+ Fe can be implemented through the Fenton class. 2+ / Fe 3+ (Circulation) to maintain the system in a reaction state that is conducive to the release of uranium and associated metals.

[0043] This invention also proposes a leaching method for uranium and polymetallic resources, utilizing low-dose chemical oxidation and the aforementioned microbial combination to synergistically drive the leaching of uranium and polymetallic resources. This method is applicable to the green extraction of complex associated ores such as uranium-molybdenum, uranium-copper, uranium-cobalt, and uranium-rare earth elements, as well as low-grade ores and tailings resources. The synergistic leaching system constructed in this method includes a low-dose chemical oxidation triggering system and a multifunctional microbial combination leaching system.

[0044] The leaching method specifically includes the following steps: Step 1: Crush the ore containing uranium and associated metals to a particle size of 0.5-10 mm. The associated metals are one or more of molybdenum, vanadium, copper, cobalt, zinc, lead, nickel, germanium, tellurium, selenium, or rare earth elements, such as complex associated minerals like U-Mo, U-Cu, U-Co, and U-REE.

[0045] Step 2: Add oxidant and stabilizer, and chemically oxidize the ore for 0.5-4 hours. The oxidant can be one or more of hydrogen peroxide, percarbonate, and persulfate, preferably hydrogen peroxide; the stabilizer includes one or more of organic acids (salts), aminocarboxylic acids (salts), phosphonic acids (salts), phosphoric acid (salts), polyphosphonic acid (salts), humic acid (salts), and fulvic acid (salts), preferably one or more of citric acid, oxalic acid, humic acid, EDTA, and NTA.

[0046] The oxidation triggering system includes an oxidant (preferably H2O2) and a stabilizer (preferably citric acid). By controlling the concentrations of both at low doses, a mild and controllable oxidation environment is formed in the initial stage of the reaction. The total concentration of the oxidant added is 0.0001%-0.01% of the ore mass, preferably 0.001%; ​​the total concentration of the stabilizer added is 0.000005%-0.005% of the ore mass, preferably 0.0002%. The low-dose chemical oxidation triggering system is used to rapidly increase the system's redox potential (Eh) in the initial stage of leaching. Within 0.5-4 hours of oxidation treatment, the system's Eh significantly increases to 300-650 mV, promoting the initial transformation of U(IV) to U(VI) and other low-valence metals to soluble forms on the mineral surface, and mildly oxidizing and destroying the mineral surface structure, thereby creating favorable conditions for subsequent microbial attachment, growth, and continuous leaching.

[0047] In a preferred embodiment, the oxidation-triggered system forms the following cyclic reaction: Fe(III) + citric acid → citric acid-Fe 3+ (Complexation and dissolution) Citric acid-Fe 3+ + U(IV) → Citric acid-Fe 2+ + U(VI) (redox), In the presence of trace amounts of H2O2, a mild Fenton-like reaction system can be formed: Citric acid-Fe 2+ + H2O2→ Citric acid-Fe 3+ + •OH + OH - .

[0048] The generated reactive oxygen species participate in mineral structure destruction under controlled conditions, but due to the low dosage of oxidant, excessive free radical accumulation is avoided, thus preventing significant toxicity to microorganisms. The stabilizer works by complexing Fe... 2+ / Fe 3+ Inhibiting iron ion hydrolysis and precipitation and delaying the non-selective decomposition of H2O2 in the slurry system, maintaining Fe 2+ / Fe 3+ The continuous oxidation capacity of circulating and low-dose H2O2 enhances the sustained activation effect of the Fenton-like system on the uranium-polymetallic mineral interface.

[0049] Step 3: Add a bacterial solution containing a microbial combination to the reaction system. First, add acid-producing and complexing microorganisms and mix them evenly with the ore. After reacting for 1-4 hours, add surfactant-producing microorganisms. After reacting for another 0.5-3 hours, add specific uranium recognition microorganisms and redox-regulating microorganisms. The volume ratio of acid-producing and complexing microorganisms, surfactant-producing microorganisms, specific uranium recognition microorganisms and redox-regulating microorganisms is (1-10):(1-5):(1-10):(1-10), with the lower limit of each value being 1, preferably 3:2:5:5.

[0050] After the formation of a mild oxidizing environment, the multifunctional microbial system enters a metabolically active state: (1) acid-producing and complexing microorganisms secrete organic acids such as oxalic acid, citric acid, gluconic acid, succinic acid, and malic acid, which lower the local pH and promote the loosening of the mineral lattice structure; (2) organic acids, complexing ligands and related metabolites affect U(VI) and Cu 2+ Co 2+ MoO4 2- (2) Rare earth ions form complexes, which improve their solubility stability; (3) Surfactant-producing bacteria produce surface-active substances, which improve the penetration ability of leaching agents into ore pores and microcracks; (4) Specific uranium-recognizing bacteria preferentially attach to the surface or surrounding area of ​​uranium minerals, promote the continuous conversion of U(IV) to U(VI) and promote the synchronous leaching of associated metals; (5) Redox-regulated microorganisms enhance the activity of electron transport chain under moderate oxidation environment and accelerate redox cycle.

[0051] By using low-dose chemical oxidation triggering in steps 2 and 3 and the synergistic effect of multifunctional microorganisms, this invention can achieve continuous destruction of mineral structures and release of metal oxidation while maintaining microbial activity, thereby improving the leaching efficiency and system stability of uranium and its associated metal resources.

[0052] Step 4: Maintain the pH of the system at 1.0-8.0 and the temperature at 10-60℃ to carry out the leaching reaction, with a cycle of 2-10 days.

[0053] During the reaction, a three-layered microenvironment is formed on the surface of the mineral particles: the first layer (inner layer) is a microbial attachment layer (forming a biofilm); the second layer is an organic acid and complexing agent enrichment layer; and the third layer (outer layer) is a locally high-Eh oxidation layer. This structure helps to improve electron transfer efficiency; shorten the diffusion path; enhance the reaction rate on the mineral surface; and achieve directional leaching rather than disordered dissolution.

[0054] Efficient and synergistic leaching of multi-metal resources is achieved through various pathways, including chemical oxidation triggering, mineral interface modification, complexation stabilization, enhanced interfacial mass transfer, microbial targeted attachment oxidation, and Fe cycle regulation. Specifically, uranium is preferentially leached in the U(VI) complex state; transition metals such as copper, cobalt, and nickel are released simultaneously under acidic complexation conditions; molybdenum and rare earth elements enter the solution as anionic complexes; and the metals are leached synergistically, rather than in the stepwise processing of traditional processes.

[0055] This invention establishes a multi-level synergistic oxidation mechanism of "low-dose chemical triggering + multifunctional microbial metabolic amplification + Fe cycle maintenance," the essence of which lies in achieving a balance between reaction rate enhancement and ecological safety by constructing a controllable redox window without relying on strong oxidants. This synergistic mechanism is beneficial for improving reaction initiation efficiency, shortening the leaching cycle, promoting the synergistic release of multiple metals, and reducing chemical reagent load.

[0056] Example 1 In this embodiment, the acid-producing complexing microorganism is Cladosporium buddingum ( Cladosporium cladosporioides CICC 41760 was purchased from the China Industrial Microbial Culture Collection Center; the surfactant-producing bacterium was *Rifonsella rivastigmoides*. Leifsonia sp. CICC 25134 was purchased from the China Industrial Microbial Culture Collection Center; the specific uranium-recognizing bacterium was Brick Red Microbacterium XS6-1 ( Microbacterium testaceum XS6-1 CGMCC 28318 is deposited at the China General Microbiological Culture Collection Center; the redox-regulating microorganism is *Thiobacillus acidophilus* (CGMCC 28318). Acidithiobacillus ferrooxidans (ATCC 23270) was purchased from the American Center for Type Culture Collection.

[0057] 1. Material preparation: Select 1 kg of granite-type uranium ore containing 0.15% U and 0.08% Mo, crush it to a particle size of 4 mm, and prepare a 1 L suspension.

[0058] 2. Set up an experimental group and add 0.001% H2O2 (i.e., 10 mg / L) and 0.0002% citric acid (i.e., 2 mg / L) to the slurry system to chemically oxidize the ore for 1 hour.

[0059] Add a bacterial solution containing a microbial composite to the reaction system, starting with Cladosporium buddingii (Bacillus). C. cladosporioides Mix the mixture thoroughly with the ore, and after reacting for 2 hours, add Rifonsonia (Bacterium rivanum). Leifsonia After reacting for another hour, add brick-red microbacterium XS6-1 and acidophilic ferrous thiobacillus (sp.). A. ferrooxidans The four bacterial strains were mixed in a ratio of 3:2:5:5, with an initial density of 10 per strain. 7 -10 8 CFU / mL.

[0060] Control group 1-A: Only equal amounts of H2O2 and citric acid were added to the slurry system, without inoculating any microorganisms.

[0061] Control group 1-B: No H2O2 and citric acid were added, but only a multifunctional microbial combination was inoculated, with the same microbial composition as the experimental group.

[0062] 3. Operation: The initial pH was set to 5.0, the temperature was kept constant at 30°C, and the reaction was continued for 7 days. The concentrations of uranium and molybdenum in the leachate of different groups were dynamically monitored during the leaching process to evaluate the effects of different treatment methods on the leaching efficiency and leaching rate of U-Mo polymetallic ore. The results are as follows: Figure 1 As shown.

[0063] Conclusion and Analysis: In this embodiment, the experimental group comprehensively outperformed the control group in U-Mo leaching rate, demonstrating superior uranium-polymetallic ore leaching capability. The above results indicate that the pure chemical oxidation system, under low-dose H2O2 and citric acid conditions, can only produce limited mineral interface activation, making it difficult to support the continuous and efficient release of uranium and molybdenum; while the pure biological system has a certain continuous leaching capability, its start-up is slow, and the initial leaching rate is insufficient. The combined uranium and molybdenum leaching kinetics results show that the experimental group exhibited a significant time-series synergistic enhancement effect.

[0064] The final leaching degree of U-Mo polymetallic ore is shown in Table 1.

[0065] Table 1

[0066] Conclusion and Analysis: The synergistic leaching system of "low-dose chemical oxidation triggering + multifunctional microbial combination" described in this invention significantly improves the leaching efficiency of uranium and molybdenum in granite-type uranium-molybdenum polymetallic ores. In the experimental group, the uranium leaching rate reached 91.3%, and the molybdenum leaching rate reached 89.1%, significantly higher than that of the pure chemical oxidation leaching control group 1-A and the pure biological combination leaching control group 1-B.

[0067] Specifically, under the same pH, temperature, and reaction cycle conditions, control group 1-A, treated only with low-dose H2O2 and citric acid, showed uranium and molybdenum leaching rates of only 24.2% and 15.7%, respectively. This indicates that the low-dose chemical system, when used alone, mainly plays a mild role in mineral interface activation and is insufficient to achieve full release of uranium and molybdenum. Control group 1-B, inoculated only with a multifunctional microbial combination, achieved uranium and molybdenum leaching rates of 37.4% and 23.8%, respectively. This shows that while relying solely on microbial metabolism can promote mineral dissolution through acid production, complexation, secretion of surfactants, and redox regulation, it still suffers from limitations such as slow initiation, insufficient interface activation, and insufficient oxidation kinetics within a short 7-day cycle.

[0068] From the perspective of synergistic effects, the uranium leaching rate in the experimental group was approximately 3.77 times that of group 1-A and 2.44 times that of group 1-B, respectively; the molybdenum leaching rate in the experimental group was approximately 5.68 times that of group 1-A and 3.74 times that of group 1-B, respectively. These results indicate that the present invention achieves a significant synergistic enhancement effect between short-term chemical triggering and continuous action by multifunctional microorganisms. Especially under the conditions of an initial pH of 5.0 and a reaction cycle of only 7 days, the experimental group achieved approximately 90% efficient leaching of uranium and molybdenum, demonstrating that this method can effectively shorten the induction period of bioleaching and improve the leaching rate and resource release degree of complex uranium-molybdenum polymetallic ores.

[0069] Example 2 This embodiment uses hard-rock U-Cu-Co polymetallic ore as the research object and conducts a 10-day leaching experiment. In this embodiment, the acid-producing complexing microorganism is *Paecilomyces wanensis* (…). Paecilomyces variotii CCTCC AF2019001 was purchased from the China Center for Type Culture Collection; the surfactant-producing bacterium was *Oligotrophomonas rhizophila* (CCTCC AF2019001). Stenotrophomonas rhizophila ATCC BAA-473 was purchased from the American Center for Type Culture Collection; the specific uranium-recognizing bacterium was Brick Red Microbacterium XS6-1 ( Microbacterium testaceum XS6-1 CGMCC 28318 is deposited at the China General Microbiological Culture Collection Center; the redox-regulating microorganism is Leptospira ironophila ( Leptospirillum ferriphilum DSM 14647 was purchased from the German Microbial Culture Collection Center.

[0070] 1. Material preparation: Select 1 kg of hard rock uranium ore containing 0.17% U, 0.16% Cu and 0.11% Co, crush it to a particle size of 4 mm, and prepare 1 L of suspension.

[0071] 2. Set up an experimental group and add 0.0005% H2O2 (i.e., 5 mg / L) and 0.001% citric acid (i.e., 10 mg / L) to the slurry system to chemically oxidize the ore for 3 hours.

[0072] Add a bacterial solution containing a microbial assemblage to the reaction system, starting with *Paecilomyces wannii* (…). P. variotii After mixing evenly with the ore and reacting for 1 hour, add *Oligotrophomonas rhizophilus* (…). S. rhizophila After reacting for another 0.5 hours, add brick-red microbacterium XS6-1 and iron-loving leptospira ( L. ferriphilum The four strains were mixed in a ratio of 1:1:1:1, with an initial density of 10 per strain. 7 -10 8 CFU / mL.

[0073] Control group 2-A: Only equal amounts of H2O2 and citric acid were added to the slurry system, without inoculating any microorganisms.

[0074] Control group 2-B: No H2O2 and citric acid were added, but only a multifunctional microbial combination was inoculated, with the same microbial composition as the experimental group.

[0075] 3. Operating conditions: The initial pH of each group was set to 8.0, the temperature was kept constant at 50℃, and the reaction was continued for 10 days. The slurry was kept uniformly mixed during the reaction. After the reaction, the concentrations of uranium, copper, and cobalt in the leaching solution were measured, and the leaching rate of each target metal was calculated. The results are shown in Table 2.

[0076] Table 2

[0077] Conclusion and Analysis: After replacing the acid-producing-complexing microorganisms, surfactant-producing bacteria, and redox-regulating microorganisms in Example 1 with similar functional microorganisms, the "low-dose chemical oxidation triggering + multifunctional microbial combination" system described in this invention can still achieve efficient synergistic leaching of uranium, copper, and cobalt in U-Cu-Co polymetallic ores. The leaching rates of uranium, copper, and cobalt in the experimental group reached 92.7%, 87.4%, and 84.6%, respectively, which were significantly higher than those in the control group. This indicates that the technical effect of this invention does not depend on a single strain other than the specific uranium-recognizing microbacterium XS6-1, but mainly on the metabolic specialization, sequential inoculation, and interfacial synergistic effects among the various functional microorganisms.

[0078] Specifically, control group 2-A underwent chemical oxidation treatment using only low-dose H2O2 and citric acid, resulting in uranium, copper, and cobalt leaching rates of 24.6%, 15.1%, and 18.2%, respectively. This indicates that while the low-dose chemical oxidation system alone can produce some initial activation on the mineral surface, it lacks sustained acid production, complexation, mass transfer enhancement, and redox regulation, making it difficult to achieve sufficient release of multiple metals. Control group 2-B was inoculated only with a multifunctional microbial combination, achieving uranium, copper, and cobalt leaching rates of 57.9%, 40.5%, and 35.8%, respectively. Even without low-dose chemical oxidation triggering, the purely biological system still exhibited problems such as slow initiation, insufficient initial activation of the mineral surface, and insufficient oxidation kinetics.

[0079] In contrast, the experimental group, after low-dose H2O2-citric acid pre-oxidation treatment followed by inoculation with a multifunctional microbial ensemble, showed significantly increased uranium, copper, and cobalt leaching rates. This result indicates that the low-dose chemical oxidation stage can rapidly enhance the reactivity of the mineral interface in the early stages of the reaction, promoting initial oxidation, structural loosening, and exposure of active sites in uranium and associated metal-bearing phases. Subsequently, *Paecilomyces wanensis* promotes mineral lattice erosion and metal complex release through the secretion of organic acids and complexing metabolites; *Oligotrophomonas rhizophila* improves ore wettability and interfacial mass transfer conditions by producing surfactants and extracellular polymers; *Microbacterium rubrum* XS6-1 promotes preferential uranium release through preferential attachment to uranium minerals and directional interfacial interactions; and *Leptospira ferrophila* participates in Fe... 2+ / Fe 3+ Cyclic and local redox regulation leads to a continuous synergistic leaching process of "chemical triggering-biological amplification-redox maintenance".

[0080] In terms of synergistic effects, the uranium leaching rate in the experimental group was approximately 3.77 times and 1.60 times that of the control groups 2-A and 2-B, respectively; the copper leaching rate was approximately 5.79 times and 2.16 times that of the control groups 2-A and 2-B, respectively; and the cobalt leaching rate was approximately 4.64 times and 2.36 times that of the control groups 2-A and 2-B, respectively. These results further demonstrate that the present invention establishes a stable synergistic enhancement effect among low-dose chemical oxidation triggering, sequential inoculation of functional microorganisms, directional action of specific uranium-recognizing bacteria, and the continuous maintenance of the Fe cycle by redox-regulated microorganisms.

[0081] In summary, this embodiment demonstrates that the microbial assemblies described in this invention possess a certain degree of functional equivalence and adaptability. As long as the selected microorganisms possess functions such as acid-producing complexation, surfactant generation, specific uranium recognition, and redox regulation, and are combined according to the chemical oxidation conditions, inoculation ratio, and inoculation sequence specified in this invention, efficient synergistic leaching can be achieved in different types of hard-rock uranium-polymetallic ores. This result further illustrates that this invention has a wide range of strain compatibility and good applicability to different ore types.

[0082] Example 3: Specific adsorption experiment of uranium minerals by the brick-red microbacterium XS6-1 Uranium minerals, quartz, feldspar, pyrite, and molybdenite particles were selected, with a particle size controlled to be 75-150 μm. Brick-red microbacterium XS6-1 was cultured to the logarithmic growth phase, washed with PBS and resuspended, and the OD was adjusted. 600 Up to 0.5.

[0083] Uranium minerals were mixed with quartz, feldspar, pyrite, and molybdenite in a mass ratio of 1:20:10:10:5. A suspension of brick-red Microbeobacterium XS6-1 was added and incubated for 12 hours. The distribution of microorganisms on the surface of different mineral particles was then observed using SEM-EDS. Figure 2 As shown.

[0084] Conclusions and Analysis: In mixed mineral systems where uranium minerals coexist with quartz, feldspar, pyrite, and molybdenite, the brick-red microbacterium XS6-1 did not exhibit uniform distribution on the surfaces of various minerals, but rather displayed a clear selective enrichment characteristic. Secondary electron imaging results showed that the short rod-shaped brick-red microbacterium XS6-1 mainly adhered to local particle surfaces; backscattered imaging further indicated a good spatial correspondence between the aforementioned bacterial enrichment areas and high atomic number element enrichment areas. Combined with EDS elemental surface scanning results, it was found that Si was widely distributed in the field of view, representing the background distribution of silicate gangue minerals such as quartz and feldspar; while U showed a clear local enrichment characteristic and highly overlapped with the attachment sites of microbacterium XS6-1, indicating that the bacteria preferentially adsorbed onto the surfaces of uranium-containing mineral particles, rather than extensively adhering to the surfaces of silicate gangue minerals.

[0085] These results demonstrate that *Bretschneidera sinensis* XS6-1 possesses specific recognition and preferential attachment capabilities for uranium minerals. Under conditions of coexistence with multiple associated minerals, XS6-1 can selectively interact with the uranium mineral interface through cell surface functional groups, charge interactions, extracellular polymers, and metabolites, leading to bacterial enrichment in the uranium-rich region. This characteristic enhances the interfacial contact efficiency between the microorganism and the target uranium mineral, promoting the subsequent local enrichment of organic acids, siderophores, extracellular polymers, and redox-active substances on the uranium mineral surface, thereby enhancing the uranium mineral surface activation and uranium release processes.

[0086] Therefore, this embodiment demonstrates that in complex uranium-polymetallic mineral systems, the brick-red microbacterium XS6-1 can preferentially colonize the surface of uranium-bearing minerals, exhibiting clear uranium-mineral-specific adsorption characteristics. This specific adsorption behavior provides direct morphological and elemental distribution evidence for the directional action of the "uranium-recognizing microbacterium" on uranium minerals, improving uranium leaching selectivity and reducing ineffective effects on gangue minerals in this invention.

[0087] Experiment 1 Comparative Examples 1 to 4 are set up as shown in Table 3, and the remaining experimental steps are the same as in Example 1.

[0088] Table 3

[0089] After the chemical oxidation stage, the compound microbial culture was added according to the inoculation sequence described in Example 1, that is, Cladosporium buddingii (Cladosporium buddingii) was added first. C. cladosporioides After reacting for 2 hours, Rifonsears ( ) were added Leifsonia After reacting for another hour, add brick-red microbacteria (sp.), M. testaceum XS6-1 and Acidophilus ferrooxidans ( A. ferrooxidans The operating conditions were the same as in Example 1. After the reaction was completed, the leachate was taken, the concentrations of uranium and molybdenum were measured, and the uranium and molybdenum leaching rates were calculated, as shown in Table 4.

[0090] Table 4

[0091] Conclusion Analysis: The parameters of the chemical oxidation process have a significant impact on the synergistic leaching effect of uranium-molybdenum polymetallic ores. Under the preferred conditions of this invention, the uranium leaching rate in Example 1 reached 91.3%, and the molybdenum leaching rate reached 89.1%, which is significantly higher than the control group that deviated from the preferred parameters or lacked key components. This indicates that there is a clear synergistic effect window between low-dose oxidant, stabilizer, and appropriate chemical oxidation time.

[0092] From the perspective of chemical oxidation time, the oxidation time of Comparative Example 1 was too short, with uranium and molybdenum leaching rates of 57.6% and 51.3%, respectively. This result indicates that a short treatment time of 0.1 h is insufficient to fully activate the mineral surface; the mineral lattice loosening, exposure of active sites, and initial oxidation transformation are all inadequate, thus failing to effectively exert the "chemical triggering" effect. In Comparative Example 2, after extending the oxidation time to 8 h, the uranium and molybdenum leaching rates were 65.4% and 55.7%, respectively, higher than Comparative Example 1 but still significantly lower than Example 1. This shows that extending the oxidation time can enhance the oxidation activation of the mineral surface to some extent, but a longer chemical oxidation time is not necessarily better. Excessive oxidation treatment may lead to over-oxidation of the mineral surface, iron precipitation coverage, or passivation of local reaction interfaces, thus making it difficult to achieve the highly efficient chemical-biological time-series synergistic effect shown in Example 1.

[0093] Comparative Example 3, with only H2O2 added and no citric acid stabilizer, showed uranium and molybdenum leaching rates of 53.2% and 47.9%, respectively, significantly lower than Example 1. This demonstrates the crucial role of stabilizers in the sustained action of low-dose oxidation systems. While adding H2O2 alone can produce some initial oxidation, the lack of stabilizers hinders the effective oxidation of Fe. 2+ / Fe 3+Due to the complexation stability and inhibition of non-selective decomposition of H2O2, oxidation in the system is difficult to sustain and a stable chemo-biological synergistic interface cannot be formed. In Comparative Example 4, only citric acid was added without H2O2, and the uranium and molybdenum leaching rates were 41.5% and 28.6%, respectively, which were the lowest levels among the control groups. In particular, the molybdenum leaching rate decreased significantly, indicating that relying solely on organic acid complexation and weak acid hydrolysis is insufficient to achieve rapid oxidative conversion of U(IV) and is also insufficient to significantly promote the simultaneous release of molybdenum.

[0094] In summary, this experiment demonstrates that the key to the chemical oxidation stage lies not in simply increasing the amount of oxidant or stabilizer, nor in arbitrarily extending the oxidation time, but in controlling the amount of oxidant, the amount of stabilizer, their relative ratio, and the chemical oxidation time within appropriate ranges. Only under the preferred conditions of this invention represented in Example 1 can a low dose of H2O2 provide a moderate oxidation triggering effect, and citric acid can maintain Fe... 2+ / Fe 3+ By circulating and delaying the ineffective decomposition of the oxidant, and with a chemical oxidation time of 1 hour, the activation of the mineral interface and the maintenance of microbial activity can be simultaneously achieved, thus forming a synergistic leaching process of "low-dose chemical oxidation triggering - mineral interface activation - continuous metabolic amplification by composite microorganisms". When deviating from this parameter window, the system either has insufficient oxidation triggering, insufficient or excessive stabilizer regulation, or increased oxidative stress or intensified interface passivation, all of which will lead to a significant decrease in uranium and molybdenum leaching rates. Therefore, this experiment further demonstrates the necessity and rationality of limiting the parameter range of the chemical oxidation process in this invention.

[0095] Experiment 2 Comparative Examples 5 to 17 are set up as shown in Table 5, and the remaining experimental steps are the same as in Example 1.

[0096] Table 5

[0097] After the low-dose chemical oxidation treatment of each group was completed, bioleaching was carried out according to the microbial composition, inoculation ratio, inoculation order and inter-microbial interaction time listed in Table 5. The operating conditions were the same as in Example 1. After the reaction was completed, the leachate was taken, the uranium and molybdenum concentrations were measured, and the uranium and molybdenum leaching rates were calculated, as shown in Table 6.

[0098] Table 6

[0099] Conclusion Analysis: Table 6 shows that, under the same low-dose chemical oxidation conditions, the bioleaching process parameters have a significant impact on the synergistic leaching effect of uranium-molybdenum polymetallic ores. Example 1, using the preferred conditions of this invention—namely, a complete combination of four types of functional microorganisms, an inoculum volume ratio of 3:2:5:5, an appropriate inoculum concentration, and a phased sequential inoculum method—achieved uranium and molybdenum leaching rates of 91.3% and 89.1%, respectively, significantly higher than the groups with deviations from these bioprocess parameters. This result indicates that the efficient leaching effect of this invention not only stems from low-dose chemical oxidation triggering but also depends on the complete composition, balanced proportions, and sequential synergy among the multifunctional microorganisms.

[0100] From the perspective of microbial composition, the uranium and molybdenum leaching rates were significantly lower than in Example 1 after Comparative Examples 5-8 lacked one type of functional microorganism. Specifically, Comparative Example 5, lacking acid-producing-complexing microorganisms, saw its uranium and molybdenum leaching rates drop to 62.5% and 59.7%, respectively. This indicates that without the initial organic acid secretion, mineral lattice erosion, and metal complexation release, the mineral interface is difficult to be fully modified, hindering the subsequent effective function of the functional bacteria. Comparative Example 6, lacking surfactant-producing bacteria, had uranium and molybdenum leaching rates of 70.4% and 61.9%, respectively. This suggests that without interfacial wetting, pore penetration, and mass transfer enhancement, the effective contact between ore particles, leachate, and microorganisms is limited, particularly hindering the continuous release of molybdenum. Comparative Example 7, lacking the specific uranium recognition bacterium XS6-1, saw uranium and molybdenum leaching rates decrease to 55.8% and 52.6%, respectively, indicating that XS6-1 plays a crucial role in the directional recognition, preferential attachment, and interface-enhanced leaching of uranium minerals. While the system retained its acid production, interfacial mass transfer, and redox regulation functions without this bacterium, the directional leaching ability of uranium minerals was significantly weakened. Comparative Example 8, lacking redox-regulating microorganisms, saw uranium and molybdenum leaching rates of 60.7% and 49.8%, respectively, with a particularly significant decrease in molybdenum leaching rate, indicating that Fe... 2+ / Fe 3+ Cyclic maintenance and local Eh regulation play important roles in the synergistic release of uranium and molybdenum. The above results indicate that the four types of functional microorganisms perform different functions, including mineral interface modification, mass transfer enhancement, uranium-directed recognition, and redox maintenance; the absence of any one type will disrupt the complete synergistic chain.

[0101] From the perspective of inoculation ratio, although Comparative Examples 9-12 all retained four types of functional microorganisms, the leaching effect was still lower than that of Example 1 because the proportion of one type of functional bacteria deviated from the appropriate range. Comparative Example 9 had an excessively high proportion of acid-producing-complexing microorganisms, with uranium and molybdenum leaching rates of 79.6% and 70.2%, respectively, which were relatively higher than other deviation groups, but still significantly lower than Example 1. This indicates that enhancing acid production and complexation functions can promote metal release to some extent, but an excessively high proportion of acid-producing bacteria cannot replace the synergistic effect of specific uranium recognition and redox regulation. Excessive metabolites may also cause local environmental imbalance or enhanced interfacial coverage. Comparative Example 10 had an excessively high proportion of surfactant-producing bacteria, with uranium and molybdenum leaching rates of 70.3% and 62.5%, respectively. This indicates that excessive surfactants or extracellular polymers do not necessarily continuously improve the leaching effect; instead, they may lead to biofilm coverage, unstable interfacial mass transfer structures, or enhanced competition among functional bacteria. Comparative Example 11 showed an excessively low proportion of the specific uranium recognition bacterium XS6-1, resulting in uranium and molybdenum leaching rates of 50.9% and 54.1%, respectively. The decrease in uranium leaching rate was particularly significant, indicating that XS6-1 is the core functional bacterium for achieving directional attachment and preferential leaching of uranium minerals, and its insufficient proportion directly weakens the selective release of uranium. Comparative Example 12 showed an excessively low proportion of redox-regulating microorganisms, resulting in uranium and molybdenum leaching rates of 58.4% and 51.5%, respectively. This indicates that when the proportion of redox-regulating microorganisms is insufficient, the Fe cycle and local Eh maintenance capacity decrease, making it difficult to sustain subsequent oxidation drive after low-dose chemical oxidation triggering, thus limiting the release of both uranium and molybdenum. As seen in Comparative Examples 9-12, a reasonable proportion of the four types of functional bacteria needs to be maintained; arbitrarily increasing or decreasing any one type of bacteria does not necessarily lead to efficient leaching.

[0102] Regarding the inoculation sequence, Comparative Examples 13-15 all deviated from the preferred inoculation method of this invention, resulting in lower uranium and molybdenum leaching rates compared to Example 1. In Comparative Example 13, the specific uranium recognition bacterium XS6-1 was inoculated earlier, resulting in uranium and molybdenum leaching rates of 64.2% and 58.3%, respectively. This indicates that before the acid-producing-complexing microorganisms and surfactant-producing bacteria complete the mineral interface modification, XS6-1 cannot form a stable and efficient directional attachment layer for uranium minerals, and its specific recognition and interface strengthening effects cannot be fully utilized. In Comparative Example 14, redox-regulating microorganisms were inoculated earlier, resulting in uranium and molybdenum leaching rates of 67.5% and 56.9%, respectively. This suggests that if the Fe cycle and Eh regulation processes occur earlier than the mineral interface acidification, complexation, and mass transfer modification processes, they are prone to being out of sync with the subsequent mineral dissolution process, leading to the redox regulation effect not being effectively converted into sustained leaching capacity. In Comparative Example 15, four types of microorganisms were inoculated simultaneously. The uranium and molybdenum leaching rates were 71.6% and 63.7%, respectively. Although these rates were higher than those of Comparative Examples 13 and 14, they were still lower than those of Example 1. This indicates that simultaneous inoculation can create a certain synergistic effect among multiple microorganisms. However, the lack of a clear lead interface modification stage makes it easy for competitive attachment and overlapping metabolic processes between different functional bacteria to occur, making it difficult to achieve the synergistic effect of optimal inoculation timing.

[0103] From the perspective of inter-bacterial interaction time, the interaction time of Comparative Example 16 was too short, with uranium and molybdenum leaching rates of 62.3% and 55.2%, respectively. This result indicates that when the interaction time of acid-complexing microorganisms and surfactant-producing bacteria is insufficient, mineral surface acidification, complexation, wetting, and mass transfer modification are not fully established, resulting in a lack of suitable colonization and reaction interfaces for subsequent XS6-1 and redox-regulated microorganisms. In Comparative Example 17, the interaction time was too long, with uranium and molybdenum leaching rates of 76.4% and 63.5%, respectively, higher than Comparative Example 16 but still lower than Example 1. This suggests that extending the interaction time of the lead bacteria can enhance some mineral interface modification and initial metal release, but cannot further improve to the optimal conditions. Excessive lead interaction may lead to local acidification, excessive accumulation of organic metabolites, or enhanced biofilm coverage, while delaying the entry of XS6-1 and redox-regulated microorganisms into the optimal reaction window, thereby weakening the overall temporal synergistic efficiency.

[0104] In summary, this experiment demonstrates that, under consistent low-dose chemical oxidation triggering conditions, the microbial composition, inoculation ratio, total inoculation concentration, inoculation sequence, and inter-microbial interaction time during the bioleaching stage are all key parameters affecting the efficient synergistic leaching of uranium and molybdenum. The preferred embodiment of this invention is not a simple mixture of multiple microorganisms, but rather a continuous synergistic process constructed through the complete combination, reasonable proportion, and phased introduction of four types of functional microorganisms: "acid-producing complexation leader modification - interface mass transfer enhancement - XS6-1 directional recognition and attachment - redox regulation and maintenance." The absence of any one type of key functional microorganism, or deviations in the inoculation ratio, total inoculation amount, inoculation sequence, or interaction time from the appropriate range, will lead to varying degrees of decrease in uranium and molybdenum leaching rates. Therefore, this experiment further proves the necessity and rationality of limiting the microbial composition and bioleaching process parameters in this invention.

[0105] The above are merely preferred embodiments of the present invention. Although the present invention has been described in detail above with general descriptions, specific embodiments, and experiments, some modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A microbial assemblages for leaching uranium and polymetallic resources, characterized in that, It includes acid-producing complexing microorganisms, surfactant-producing bacteria, specific uranium-recognizing bacteria and redox-regulating microorganisms, wherein the volume ratio of the acid-producing complexing microorganisms, the surfactant-producing bacteria, the specific uranium-recognizing bacteria and the redox-regulating microorganisms is (1-10):(1-5):(1-10):(1-10).

2. The microbial assemblages according to claim 1, characterized in that, The acid-producing-complexing microorganisms are one or more of the following: *Arthrobacter*, *Amycosis*, *Cladosporium*, *Morchella*, *Penicillium*, *Streptococcus*, *Pandora*, and *Massezia*.

3. The microbial assemblages according to claim 1, characterized in that, The surfactant-producing bacteria are one or more of the following: Trichomonas vaginalis, Agrobacterium, Sphingosine monocytogenes, Oligotrophoblastus, Rifsonella, and Mycobacterium.

4. The microbial assemblages according to claim 1, characterized in that, The specific uranium-recognizing bacterium is BrickRed Microbacterium XS6-1.

5. The microbial assemblages according to claim 1, characterized in that, The redox-regulating microorganisms are one or more of the following: Thiobacillus, Leptospira, Fertilizer, Acid Microbes, and Bacillus sulfide.

6. A leaching method for uranium and polymetallic resources, characterized in that, The leaching of uranium and polymetallic resources is driven synergistically by chemical oxidation and the microbial combination described in any one of claims 1-5.

7. The leaching method according to claim 6, characterized in that, Includes the following steps: Step 1: Crush the ore containing uranium and associated metals to a particle size of 0.5-10 mm; Step 2: Perform chemical oxidation treatment on the ore for 0.5-4 hours; Step 3: Add the bacterial solution containing the microbial combination to the reaction system. First, add the acid-producing-complexing microorganisms and mix them evenly with the ore. After reacting for 1-4 hours, add the surfactant-producing bacteria. After reacting for another 0.5-3 hours, add the specific uranium recognition bacteria and the redox-regulating microorganisms. The volume ratio of the acid-producing-complexing microorganisms, the surfactant-producing bacteria, the specific uranium recognition bacteria, and the redox-regulating microorganisms is (1-10):(1-5):(1-10):(1-10). Step 4: Maintain the pH of the system at 1.0-8.0 and the temperature at 10-60℃ to carry out the leaching reaction, with a cycle of 2-10 days.

8. The leaching method according to claim 7, characterized in that, The chemical oxidation process includes the addition of an oxidant and a stabilizer. The oxidant includes one or more of hydrogen peroxide, percarbonate, and persulfate. The stabilizer includes one or more of organic acids, organic acid salts, aminocarboxylic acids, aminocarboxylic acids, phosphonic acids, phosphonates, phosphoric acid, phosphates, polyphosphoric acid, polyphosphates, humic acid, humates, fulvic acid, and fulvicates.

9. The leaching method according to claim 8, characterized in that, The total concentration of the oxidant is 0.0001%-0.01% of the mass of the ore; the total concentration of the stabilizer is 0.000005%-0.005% of the mass of the ore.

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