Method and device for leaching argillaceous sandstone uranium ore based on recyclable activating material

Abstract

The invention discloses an argillaceous sandstone uranium ore leaching method and device based on a recyclable activation material, and relates to the technical field of uranium ore resource development. The preparation method of the recyclable activated material comprises the following steps: adding WS2 and Fe3O4 into an aqueous solution, uniformly stirring, adding a boron-containing compound, a fluorine-containing precursor aqueous solution and a nitrogen-oxygen-containing compound, uniformly stirring, heating, stirring for reaction, filtering, washing and drying to obtain a precursor; and calcining the precursor in a protective atmosphere to obtain F / O co-doped h-BN / WS2 / Fe3O4 which is used as a recoverable activation material. The obtained recoverable activated material has good catalytic performance, can be widely applied to preparation of a catalyst for leaching uranium from argillaceous sandstone uranium ore, and can generate strong turbulence, secondary circulation and near-wall shear force for high-viscosity ore pulp and efficiently excite the catalytic activity of a piezoelectric material in cooperation with the device provided by the invention.

Description

Technical Field

[0001] This invention relates to the field of uranium resource development technology, and more specifically, to a method and apparatus for leaching uranium ore from mudstone sandstone based on recyclable activated materials. Background Technology

[0002] Uranium, as an important nuclear energy resource, requires efficient and green extraction technologies for its production, which are crucial for ensuring national energy security. Muddy sandstone uranium deposits are one of the main types of uranium deposits, but their ores are rich in clay minerals. The presence of these minerals poses a serious challenge to traditional leaching processes: on the one hand, clay minerals have a strong adsorption and encapsulation effect on uranium, making it difficult for some uranium (especially uranium in the tetravalent state (U(IV))) to effectively contact the leaching agent; on the other hand, clay minerals themselves easily swell, disperse, and even dissolve when exposed to water, severely clogging ore pores and greatly hindering the flow and diffusion of the leaching solution, resulting in poor permeability and low leaching rates during heap leaching.

[0003] To address the challenges of leaching uranium ore from argillaceous sandstone, strong oxidants (such as potassium permanganate and chlorates) or strong acid / base conditions are used to oxidize insoluble U(IV) to readily soluble U(VI), thereby improving leaching efficiency. However, these methods suffer from drawbacks such as high chemical reagent consumption, high cost, potential secondary pollution, equipment corrosion, and poor adaptability to complex ore bodies, resulting in poor environmental friendliness and economic viability. Hydrogen peroxide (H₂O₂), as a relatively clean oxidant, produces hydroxyl radicals with extremely strong oxidizing power, which can be used to oxidize U(IV). However, H₂O₂ decomposes slowly under natural conditions, requiring external energy (such as ultraviolet light, heat, etc.) or catalysts for activation. This is difficult and energy-intensive to implement in complex slurry systems, limiting its widespread application.

[0004] In recent years, piezoelectric catalysis, as an emerging field that utilizes mechanical energy to drive chemical reactions, has provided a new approach for generating reactive oxygen species under mild conditions. This technology utilizes the polarization of piezoelectric materials under mechanical stress to generate a built-in electric field, thereby driving electron-hole separation to activate molecular oxygen or H2O2 to generate free radicals. However, applying piezoelectric catalysis to uranium leaching still faces many challenges: First, materials with efficient piezoelectric response capabilities under weak mechanical forces (such as fluid shear forces) need to be developed; second, reaction devices that can efficiently and centrally convert the mechanical energy of uranium-bearing slurry flow into stress acting on piezoelectric materials need to be designed; finally, the entire system needs to be specifically optimized for the high viscosity and complex composition of argillaceous sandstone slurries.

[0005] In view of this, the present invention is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a method and apparatus for leaching uranium ore from argillaceous sandstone based on recyclable activated materials. This invention can efficiently oxidize and dissociate U(IV) adsorbed and encapsulated by clay minerals, while avoiding the use of large amounts of highly corrosive chemical reagents and strong acid environments, thus achieving efficient, economical and environmentally friendly leaching of uranium ore from argillaceous sandstone.

[0007] This invention is implemented as follows: In a first aspect, the present invention provides a method for preparing a recyclable activated material, comprising: S1. Add WS2 and Fe3O4 to an aqueous solution, stir until homogeneous, then add a boron-containing compound, a fluorine-containing precursor aqueous solution, and a nitrogen-oxygen-containing compound, and stir to obtain a homogeneous suspension. S2. The homogeneous suspension is heated and stirred to react, then filtered, washed, and dried to obtain F / O co-doped solution. h -BN / WS2 / Fe3O4 precursor; S3, F / O co-doping h The -BN / WS2 / Fe3O4 precursor was calcined under a protective atmosphere to obtain F / O co-doped material. h -BN / WS2 / Fe3O4, as a recyclable activation material.

[0008] In an optional embodiment, based on a volume of 50 mL of the aqueous solution, the amount of WS2 added is 0.5~1.5 g; And / or, the amount of Fe3O4 added is 0.1~1.0g; And / or, the amount of the boron-containing compound added is 0.01~1.0g; And / or, the amount of the fluorine-containing precursor aqueous solution added is 0.01~1mL, and the concentration of the fluorine-containing precursor aqueous solution is 0.01-0.05mol / L; And / or, the amount of the nitrogen-containing compound added is 0.1~10g.

[0009] In an optional embodiment, the boron-containing compound includes boric acid; And / or, the aqueous solution of the fluorinated precursor includes at least one of ammonium fluoride and sodium fluoride; And / or, the nitrogen-containing compounds include urea.

[0010] In an optional embodiment, the temperature of the stirring reaction is 60~95℃ and the time is 4~12 h; And / or, the calcination temperature is 600~1200℃, and the time is 3~10 h.

[0011] In a second aspect, the present invention provides a recyclable activation material, which is prepared by using the preparation method of the recyclable activation material described in any one of the above embodiments.

[0012] In a third aspect, the present invention provides a method for leaching argillaceous sandstone uranium ore based on a recyclable activation material, which includes placing the recyclable activation material described in the above embodiments in an argillaceous sandstone uranium ore pulp, adding a H2O2 solution to obtain a mixed solution, placing the mixed solution in a spiral catalytic reaction device, and after multiple catalytic cycle reactions, performing solid-liquid separation to obtain a leaching solution and leaching residues; wherein, the spiral catalytic reaction device is provided with a spiral tube, and the inner wall of the spiral tube is provided with protrusions and thread grooves, and both the protrusions and the thread grooves are multiple and arranged alternately.

[0013] In an optional embodiment, the diameter of the spiral tube is 2-3 cm, the height of the protrusion is 0.3-0.5 cm, and the depth of the thread groove is 0.4-0.6 cm; and / or, the axial distance between any two adjacent protrusions is 8-12 cm; and / or, the pitch of the thread groove is 8-12 cm.

[0014] In an optional embodiment, the protrusion includes a first side wall and a second side wall forming a "V" shape, the top ends of the first side wall and the second side wall are connected to form the tip of the protrusion, the bottom end of the first side wall is connected to the inner wall of the spiral tube, the bottom end of the second side wall is connected to the inner wall of the spiral tube, and the bottom ends of the first side wall and the second side wall are spaced apart; the included angle between the first side wall and the second side wall is 100-150°.

[0015] In an optional embodiment, the solid-liquid ratio of the recyclable activation material, the argillaceous sandstone uranium ore pulp and the H2O2 solution is 120-180 mg: 100 mL: 1.2-1.8 mL, wherein, the concentration of the argillaceous sandstone uranium ore pulp is 8-12 g / L, and the concentration of the H2O2 solution is 0.4-0.6 mol / L.

[0016] In a fourth aspect, the present invention provides a device for implementing the method for leaching argillaceous sandstone uranium ore based on a recyclable activation material described in any one of the above embodiments, which includes a spiral catalytic reaction device; the spiral catalytic reaction device is provided with a spiral tube, and the inner wall of the spiral tube is provided with protrusions and thread grooves, and both the protrusions and the thread grooves are multiple and arranged alternately.

[0017] The present invention has the following beneficial effects: The preparation method of the recyclable activation material provided by the present invention, through co-doping of F and O elements h-BN significantly disrupts h The lattice symmetry of -BN greatly enhances the piezoelectric response of the material under weak mechanical forces, thereby efficiently activating H2O2 to generate reactive oxygen free radicals. These free radicals can penetrate deep into the pores and surface of clay minerals, efficiently oxidizing adsorbed and encapsulated U(IV) to soluble U(VI), achieving "chemical dissociation" at the source. WS2 and Fe3O4 serve as supports; Fe3O4 imparts magnetic recyclability to the material, allowing for magnetic recovery after subsequent leaching, reducing catalyst usage costs. WS2 can also react with... h -BN forms heterojunctions, effectively promoting the separation of piezoelectric charges and further synergistically improving catalytic oxidation efficiency. The prepared recyclable activated material has good catalytic performance and can be widely used in the preparation of catalysts for uranium leaching from argillaceous sandstone uranium ore. Correspondingly, the leaching method for argillaceous sandstone uranium ore based on recyclable activated materials provided by this invention uses the above-mentioned recyclable activated material as a catalyst, and is also equipped with a spiral catalytic reaction device. This spiral catalytic reaction device, through the setting of alternating protrusions and spiral grooves, can generate strong turbulence, secondary circulation and near-wall shear force for high-viscosity slurries, prolong the collision probability and reaction time between slurry and catalyst, and improve the diffusion efficiency of hydroxyl radicals. This design cleverly concentrates the mechanical energy of slurry flow into continuous and strong stress, efficiently stimulating the catalytic activity of piezoelectric materials, alleviating the adsorption and encapsulation effect of clay minerals on uranium, and effectively preventing blockage caused by clay minerals, ensuring the adaptability of the process in complex ore bodies. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of the spiral catalytic reaction device provided by the present invention; Figure 2 A schematic diagram of the internal structure of the threaded tube of the spiral catalytic reaction device provided by the present invention in the axial direction; Figure 3 A schematic cross-sectional view of the threaded tube of the spiral catalytic reaction device provided by the present invention; Figure 4 The recyclable activated material (F / O co-doped) prepared in Example 1 of this invention h A transmission electron microscope (TEM) schematic diagram of -BN / WS2 / Fe3O4.

[0020] Icons: 100-Spiral catalytic reactor; 110-Spiral tube; 111-Protrusion; 112-Threaded groove; 113-First sidewall; 114-Second sidewall; 115-Inlet; 116-Outlet. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0022] This invention provides a method for preparing a recyclable activated material, comprising: S1. Add WS2 and Fe3O4 to an aqueous solution, stir until homogeneous, then add a boron-containing compound, a fluorine-containing precursor aqueous solution, and a nitrogen-oxygen-containing compound, and stir to obtain a homogeneous suspension. S2. The homogeneous suspension is heated and stirred to react, then filtered, washed, and dried to obtain F / O co-doped material. h -BN / WS2 / Fe3O4 precursor; S3, F / O co-doping h The -BN / WS2 / Fe3O4 precursor was calcined under a protective atmosphere to obtain F / O co-doped material. h -BN / WS2 / Fe3O4, as a recyclable activation material.

[0023] The recyclable activating material provided by this invention is mainly used in conjunction with H2O2 solution to achieve activated leaching of argillaceous sandstone uranium ore. In this invention, a wet chemical method is used, with boron-containing compounds as the boron source, nitrogen-oxygen-containing compounds as the oxygen and nitrogen sources, and an aqueous solution of a fluorine-containing precursor as the fluorine source. By mixing these materials, uniform dispersion of each raw material is achieved, constructing a stable mixed system. Subsequently, the reaction is heated, and through stirring under mild conditions, in-situ generation of h-BN and preliminary F / O co-doping are achieved. h The composite molding of -BN / WS2 / Fe3O4 yields a structurally stable precursor. Subsequent filtration and washing steps remove unreacted boron-containing compounds, fluorine-containing precursors, and decomposition products of nitrogen- and oxygen-containing compounds, preventing residual impurities from affecting the uranium leaching performance of the final material. Drying removes free water and water of crystallization, stabilizing the precursor structure and laying the foundation for structural optimization during subsequent calcination. Combined with inert atmosphere calcination, this achieves a perfected crystal structure, stable solid solution of doped atoms, and strengthened interfacial bonding, enabling in-situ growth of F / O co-doped material on the surfaces of WS2 and Fe3O4. h -BN nanosheets are ultimately used to form F / O co-doped structures with highly efficient uranium leaching performance. h-BN / WS2 / Fe3O4.

[0024] The recyclable activated material provided by this invention is co-doped with F and O elements. h -BN significantly disrupts h The lattice symmetry of -BN greatly enhances the piezoelectric response of the material under weak mechanical forces, thereby efficiently activating H2O2 to generate reactive oxygen free radicals. These free radicals can penetrate deep into the pores and surface of clay minerals, efficiently oxidizing adsorbed and encapsulated U(IV) to soluble U(VI), achieving "chemical dissociation" at the source. WS2 and Fe3O4 serve as supports; Fe3O4 imparts magnetic recyclability to the material, allowing for magnetic recovery after subsequent leaching, reducing catalyst usage costs. WS2 can also react with... h -BN forms a heterojunction, which effectively promotes the separation of piezoelectric charges and further synergistically improves the catalytic oxidation efficiency.

[0025] Based on an aqueous solution volume of 50 mL, the addition amounts of WS2 are 0.5–1.5 g; Fe3O4 is 0.1–1.0 g; boron-containing compounds are 0.01–1.0 g; fluorine-containing precursor aqueous solution is 0.01–1 mL; and nitrogen- and oxygen-containing compounds are 0.1–10 g.

[0026] Among them, boron-containing compounds include boric acid; the concentration of the aqueous solution of the fluorine-containing precursor is 0.01-0.05 mol / L; the aqueous solution of the fluorine-containing precursor includes, but is not limited to, aqueous solutions of ammonium fluoride or sodium fluoride. Nitrogen- and oxygen-containing compounds include urea.

[0027] After the above components are mixed evenly, the mixture is heated and stirred during the reaction. The temperature of the stirring reaction is 60-95℃, and the time is 4-12 h. Heating allows the boron and nitrogen in the above components to react and form a boron nitride precursor, which then forms F / O co-doping during the subsequent calcination process. h -BN / WS2 / Fe3O4. Calcination can be carried out in a tubular furnace or other conventional calcination equipment at a temperature of 600~1200℃ for 3~10 h.

[0028] The recyclable activated material prepared by the above method exhibits excellent catalytic performance and is magnetic, allowing for magnetic recovery and reducing catalyst usage costs. This material system eliminates the need for large quantities of highly corrosive chemical oxidants, thus achieving a greener uranium leaching process. This recyclable activated material can be widely used in the preparation of catalysts for uranium leaching from argillaceous sandstone uranium ore.

[0029] Specifically, this invention provides a method for leaching uranium ore from argillaceous sandstone based on recyclable activated materials, comprising: S1. Place the above recyclable activation material in the argillaceous sandstone uranium ore pulp, and add H2O2 solution to obtain a mixed solution.

[0030] The solid-liquid ratio of the recyclable activation material, argillaceous sandstone uranium ore pulp and H2O2 solution is 120 - 180 mg: 100 mL: 1.2 - 1.8 mL. Among them, the concentration of the argillaceous sandstone uranium ore pulp is 8 - 12 g / L, and the concentration of the H2O2 solution is 0.4 - 0.6 mol / L.

[0031] S2. Place the mixed solution in the spiral catalytic reaction device 100 (please refer to Figure 1 ), after multiple catalytic cycle reactions, perform solid-liquid separation to obtain a leaching solution and leaching residue.

[0032] Please refer to Figure 2 and Figure 3 , the spiral catalytic reaction device 100 is provided with a spiral tube 110. The two ends of the spiral tube 110 are respectively provided with a feed inlet 115 and a discharge outlet 116. The inner wall of the spiral tube 110 is provided with protrusions 111 and thread grooves 112. Both the protrusions 111 and the thread grooves 112 are multiple and arranged alternately.

[0033] Among them, the diameter of the spiral tube 110 is 2 - 3 cm, the height of the protrusion 111 is 0.3 - 0.5 cm, and the depth of the thread groove 112 is 0.4 - 0.6 cm; the axial distance between any two adjacent protrusions 111 is 8 - 12 cm; the pitch of the thread groove 112 is 8 - 12 cm.

[0034] The protrusion 111 in the present invention is a "V"-shaped protrusion 111. Specifically, the protrusion 111 includes a first side wall 113 and a second side wall 114 that form a "V" shape. The top ends of the first side wall 113 and the second side wall 114 are connected to form the tip of the protrusion 111. The bottom end of the first side wall 113 is connected to the inner wall of the spiral tube 110, and the bottom end of the second side wall 114 is connected to the inner wall of the spiral tube 110. The bottom ends of the first side wall 113 and the second side wall 114 are spaced apart; the included angle between the first side wall 113 and the second side wall 114 is 100 - 150°.

[0035] In this invention, by defining the structure of the spiral catalytic reactor 100, when the high-viscosity slurry flows axially along the spiral tube 110, it first contacts the alternating "V"-shaped protrusions 111. Since the first sidewall 113 and the second sidewall 114 of the protrusions 111 form an angle of 100-150° and are spaced apart at their bottom ends, the slurry flow is split into two streams by the tips of the protrusions 111, flowing along the sidewalls towards the inner wall of the spiral tube 110 (splitting effect). Simultaneously, the height of the protrusions 111 is 0.3-0.5 cm (accounting for 10%-16.7% of the diameter of the spiral tube 110). This size matches the boundary layer thickness of the high-viscosity slurry, effectively penetrating the boundary layer, breaking the laminar flow state of the slurry, and forming local eddies (turbulence effect). In addition, the axial distance between any two adjacent protrusions 111 is 8-12cm (consistent with the pitch of the threaded groove 112), ensuring that when the eddy current generated by the previous protrusion 111 has not decayed, the next protrusion 111 continues to apply disturbance, so that the turbulence state is continuously strengthened.

[0036] The spiral grooves 112 on the inner wall of the spiral tube 110 have a depth of 0.4-0.6 cm (accounting for 13.3%-20% of the diameter of the spiral tube 110) and a pitch of 8-12 cm. Their spiral structure causes the slurry to flow axially while simultaneously undergoing circumferential rotational motion (spiral guiding effect). This rotational motion, combined with the radial vortices generated by the herringbone-shaped protrusions 111, forms a three-dimensional flow field, further disrupting the continuity of the slurry flow and transforming the high-viscosity slurry from "laminar-transitional flow" to "strong turbulence." Simultaneously, the depth of the spiral grooves 112 is greater than the height of the protrusions 111, forming an alternating "convex-concave" wall structure. This creates a velocity gradient between the slurry flow velocity within the grooves and at the protrusions 111 (slower velocity within the grooves, faster velocity at the protrusions 111), further intensifying the turbulence.

[0037] The spiral guidance of the threaded groove 112 generates circumferential velocity in the slurry, while the diversion effect of the herringbone-shaped protrusion 111 creates a radial velocity difference in the slurry (lower velocity near the pipe wall and higher velocity at the pipe center), forming a three-dimensional velocity gradient of axial-circumferential-radial. According to fluid mechanics principles, the velocity gradient induces shear flow in the fluid, thereby inducing secondary circulation (i.e., additional circulating flow outside the main flow direction). For example, after the slurry is diverted on both sides of the protrusion 111, part of it flows along the pipe wall to the groove, and the other part flows along the pipe center. The two form a circulating backflow at the junction of the groove and the protrusion 111, achieving internal mixing and disturbance of the slurry.

[0038] The protrusions 111 and the threaded grooves 112 on the inner wall of the spiral tube 110 form an alternating "peak-valley" structure. During the flow of the slurry, the sidewalls of the protrusions 111 and the sidewalls of the grooves exert a direct shearing effect on the slurry. Since the height of the protrusions 111 (0.3-0.5 cm) and the depth of the grooves (0.4-0.6 cm) match the viscosity characteristics of the high-viscosity slurry, the shearing effect can directly act on the particle agglomerates (especially clay mineral agglomerates) inside the slurry, breaking the adsorption forces between particles. At the same time, the secondary circulation allows the slurry to continuously scour the tube wall, avoiding the concentration of shearing effect in a fixed area and forming a uniformly distributed near-wall shear force field.

[0039] This application utilizes the synergistic design of protrusions 111 and threaded grooves 112 to concentrate the mechanical energy (kinetic energy and pressure energy) of the slurry flow into turbulent pulsating stress, shear stress, and circulating impact stress. These stresses continuously act on the piezoelectric material mixed in the slurry, causing the piezoelectric material to undergo continuous mechanical deformation, thereby stimulating its piezoelectric effect (charge separation) and significantly enhancing its catalytic activity.

[0040] Intense turbulence and secondary circulation prevent clay mineral particles in the slurry from being stably adsorbed onto the surface of uranium ions (fluid disturbance disrupts adsorption equilibrium); near-wall shear forces directly strip the uranium ions already adsorbed on the surface of the clay minerals, or break the clay minerals' encapsulation structure of uranium, allowing the uranium ions to be fully exposed within the effective range of the recyclable activation material, thus improving uranium leaching efficiency. Furthermore, intense turbulence and secondary circulation also prevent the stable deposition of clay mineral aggregates. The spiral guiding effect of the threaded groove 112 causes the slurry to rotate and flow along the pipe wall, creating a "self-cleaning" effect. The alternating structure of the protrusions 111 and grooves ensures that there is no smooth deposition surface on the pipe wall, further inhibiting the deposition and clogging of clay minerals, ensuring the adaptability of the process in complex ore bodies (high clay content, high viscosity slurry).

[0041] Therefore, the leaching method for uranium ore from argillaceous sandstone based on recyclable activated materials provided by this invention uses the aforementioned recyclable activated materials as catalysts, and is also equipped with a spiral catalytic reactor 100. This spiral catalytic reactor 100, through the arrangement of alternating protrusions 111 and threaded grooves 112, can generate strong turbulence, secondary circulation, and near-wall shear forces for high-viscosity slurries. This design cleverly concentrates the mechanical energy of the slurry flow into continuous and intense stress, efficiently stimulating the catalytic activity of the piezoelectric material, alleviating the adsorption and encapsulation effects of clay minerals on uranium, and effectively preventing blockage caused by clay minerals, ensuring the adaptability of the process in complex ore bodies.

[0042] Furthermore, the present invention provides an apparatus for implementing the above-mentioned leaching method for uranium ore from mudstone sandstone based on recyclable activated materials, which includes a spiral catalytic reaction apparatus 100; the specific structure of the spiral catalytic reaction apparatus 100 can be found in the above description and will not be repeated here.

[0043] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0044] Example 1 This embodiment provides a recyclable activation material (F / O co-doped) h A method for preparing (-BN / WS2 / Fe3O4), the method comprising: (1) Add 1.0 g WS2 and 0.5 g natural Fe3O4 to 50 mL of aqueous solution, stir for 30 min, then add 0.5 g boric acid, 0.3 mL 0.01 mol / L fluorine precursor aqueous solution and 5.5 g urea, and stir to obtain a homogeneous suspension; (2) The suspension was stirred at 60°C for 4 h, filtered, washed and dried to obtain F / O co-doped solution. h -BN / WS2 precursor; (3) F / O co-doping h The -BN / WS2 / Fe3O4 precursor was placed in a tube furnace and calcined at 800℃ for 4 hours in an argon atmosphere to obtain F / O co-doped material. h -BN / WS2 / Fe3O4 uranium leaching material.

[0045] like Figure 4 As shown, the recyclable activated material (F / O co-doped) prepared in Example 1 of this invention h Microstructure diagram of BN / WS2 / Fe3O4. As shown in the figure, WS2 and... h Both -BN exhibit a plate-like structure with close contact between them, which also facilitates efficient electron transfer. Fe3O4 nanoparticles are uniformly dispersed on the surface of the recyclable activated material.

[0046] This embodiment also provides a method for leaching uranium ore from argillaceous sandstone based on recyclable activated materials, which includes: The test ore was taken from a muddy sandstone uranium deposit in Inner Mongolia (uranium grade of 0.04%). It has fine grains and is associated with a large amount of illite, kaolinite, calcite and potassium feldspar.

[0047] 150 mg of the above-mentioned recyclable activated material was placed in 100 mL of argillaceous sandstone uranium ore slurry with a concentration of 10 g / L and a pH of 3. Then, 1.5 mL of H2O2 solution with a concentration of 0.5 mol / L was added to the suspension. The homogeneous suspension was placed in a spiral catalytic reaction device 100. After five cycles of piezoelectric catalytic experiment, solid-liquid separation was achieved by magnetic recovery treatment. The leaching residue was digested by digestion method. Then, the uranium content in the digestion solution was detected by ICP-OES. The calculation results showed that the uranium content in the leaching residue was 0.004%.

[0048] Among them, the spiral catalytic reaction device 100 is provided with a spiral tube 110. The diameter of the spiral tube 110 is 2.5 cm. The inner wall of the spiral tube 110 is provided with protrusions 111 and thread grooves 112. Both the protrusions 111 and the thread grooves 112 are multiple and arranged alternately. The height of the protrusions 111 is 0.4 cm, and the depth of the thread grooves 112 is 0.5 cm. The axial pitch of the protrusions 111 is 10 cm, and the pitch of the thread grooves 112 is 10 cm. In this embodiment, the protrusions 111 include a first side wall 113 and a second side wall 114 that form a "V" shape. The top ends of the first side wall 113 and the second side wall 114 are connected to form the tip of the protrusion 111. The bottom end of the first side wall 113 is connected to the inner wall of the spiral tube 110, and the bottom end of the second side wall 114 is connected to the inner wall of the spiral tube 110. The bottom ends of the first side wall 113 and the second side wall 114 are spaced apart; the included angle between the first side wall 113 and the second side wall 114 is 120°.

[0049] Example 2 This embodiment provides a preparation method of a recyclable activation material (F / O co-doped h -BN / WS2 / Fe3O4), and this method includes: (1) Add 1.0 g of WS2 and 0.5 g of natural Fe3O4 into 50 mL of aqueous solution. After stirring for 30 min, add 1.0 g of boric acid, 0.3 mL of 0.01 mol / L fluorine-containing precursor aqueous solution, and 8 g of urea, and stir to obtain a homogeneous suspension; (2) Place the suspension at 80 °C and continuously stir and react for 4 h, filter, wash, and dry to obtain the F / O co-doped h -BN / WS2 precursor; (3) Place the F / O co-doped h -BN / WS2 / Fe3O4 precursor in a tubular furnace and calcine it at 1000 °C for 4 h in an argon atmosphere to obtain the F / O co-doped h -BN / WS2 / Fe3O4 uranium leaching material.

[0050] The method for leaching argillaceous sandstone uranium ore based on the recyclable activation material provided in this embodiment is basically the same as that in Example 1, except that in this embodiment, the F / O co-doped h -BN / WS2 / Fe3O4 uranium leaching material prepared in Example 2 is used as the recyclable activation material for leaching uranium. The results of the above argillaceous sandstone uranium ore leaching experiment show that the uranium element content in the leaching residue is 0.002%.

[0051] Example 3 This embodiment provides a recyclable activation material (F / O co-dopedh A method for preparing (-BN / WS2 / Fe3O4), the method comprising: (1) Add 0.5 g WS2 and 0.1 g natural Fe3O4 to 50 mL of aqueous solution, stir for 30 min, then add 0.01 g boric acid, 0.01 mL 0.01 mol / L fluorine precursor aqueous solution and 0.1 g urea, and stir to obtain a homogeneous suspension; (2) The suspension was placed at 60℃ and stirred continuously for 12 h. After filtration, washing and drying, F / O co-doping was obtained. h -BN / WS2 precursor; (3) F / O co-doping h The -BN / WS2 / Fe3O4 precursor was placed in a tube furnace and calcined at 600℃ for 10 h in an argon atmosphere to obtain F / O co-doped material. h -BN / WS2 / Fe3O4 uranium leaching material.

[0052] The leaching method for uranium ore from argillaceous sandstone based on recyclable activated materials provided in this embodiment is basically the same as that in Example 1, except that this embodiment uses the F / O co-doped material prepared in Example 3. h -BN / WS2 / Fe3O4 uranium leaching material is used as a recyclable activator for leaching uranium. The results of the above leaching experiments on argillaceous sandstone uranium ore show that the uranium content in the leaching residue is 0.005%.

[0053] Example 4 This embodiment provides a recyclable activation material (F / O co-doped) h A method for preparing (-BN / WS2 / Fe3O4), the method comprising: (1) Add 1.5 g WS2 and 1.0 g natural Fe3O4 to 50 mL of aqueous solution, stir for 30 min, then add 1.0 g boric acid, 1 mL 0.05 mol / L fluorine precursor aqueous solution and 10 g urea, and stir to obtain a homogeneous suspension; (2) The suspension was stirred continuously at 95°C for 4 h, then filtered, washed, and dried to obtain F / O co-doped solution. h -BN / WS2 precursor; (3) F / O co-doping h The -BN / WS2 / Fe3O4 precursor was placed in a tube furnace and calcined at 1200℃ for 3 hours in an argon atmosphere to obtain F / O co-doped material. h -BN / WS2 / Fe3O4 uranium leaching material.

[0054] The method for leaching argillaceous sandstone uranium ore based on recyclable activated materials provided in this embodiment is basically the same as that in Embodiment 1, except that in this embodiment, the F / O co-doped h -BN / WS2 / Fe3O4 uranium leaching material is used as the recyclable activated material for leaching uranium. The results of the above argillaceous sandstone uranium ore leaching experiment show that the uranium element content in the leaching residue is 0.004%.

[0055] Embodiment 5 This embodiment is basically the same as Embodiment 1, except that in this embodiment, the spiral catalytic reaction device 100 is provided with a spiral tube 110. The diameter of the spiral tube 110 is 2 cm. The inner wall of the spiral tube 110 is provided with protrusions 111 and thread grooves 112. Both the protrusions 111 and the thread grooves 112 are multiple and arranged alternately. The height of the protrusions 111 is 0.3 cm, and the depth of the thread grooves 112 is 0.4 cm. The axial pitch of the protrusions 111 is 8 cm, and the pitch of the thread grooves 112 is 8 cm. In this embodiment, the protrusions 111 include a first side wall 113 and a second side wall 114 that form a "human" shape. The top ends of the first side wall 113 and the second side wall 114 are connected to form the tip of the protrusion 111. The bottom end of the first side wall 113 is connected to the inner wall of the spiral tube 110, and the bottom end of the second side wall 114 is connected to the inner wall of the spiral tube 110. The bottom ends of the first side wall 113 and the second side wall 114 are spaced apart; the included angle between the first side wall 113 and the second side wall 114 is 100°.

[0056] The results of the above argillaceous sandstone uranium ore leaching experiment show that the uranium element content in the leaching residue is 0.006%.

[0057] Embodiment 6 This embodiment is basically the same as Embodiment 1, except that in this embodiment, the spiral catalytic reaction device 100 is provided with a spiral tube 110. The diameter of the spiral tube 110 is 3 cm. The inner wall of the spiral tube 110 is provided with protrusions 111 and thread grooves 112. Both the protrusions 111 and the thread grooves 112 are multiple and arranged alternately. The height of the protrusions 111 is 0.5 cm, and the depth of the thread grooves 112 is 0.6 cm. The axial pitch of the protrusions 111 is 12 cm, and the pitch of the thread grooves 112 is 12 cm. In this embodiment, the protrusions 111 include a first side wall 113 and a second side wall 114 that form a "human" shape. The top ends of the first side wall 113 and the second side wall 114 are connected to form the tip of the protrusion 111. The bottom end of the first side wall 113 is connected to the inner wall of the spiral tube 110, and the bottom end of the second side wall 114 is connected to the inner wall of the spiral tube 110. The bottom ends of the first side wall 113 and the second side wall 114 are spaced apart; the included angle between the first side wall 113 and the second side wall 114 is 150°.

[0058] The results of the above leaching experiments on uranium ore in argillaceous sandstone show that the uranium content in the leaching residue is 0.004%.

[0059] Comparative Example 1 This comparative example is basically the same as Example 1, except that in this comparative example, sodium fluoride aqueous solution is not added in step (1) when preparing the recyclable activated material, and urea is adjusted to ammonia water. The product obtained is h -BN / WS2 / Fe3O4.

[0060] The above h -BN / WS2 / Fe3O4 was used as a recyclable activating material to leach uranium from argillaceous sandstone uranium ore according to the method in Example 1. The results showed that the uranium content in the leaching residue was 0.019%.

[0061] Comparative Example 2 This comparative example is basically the same as Example 1, except that in the preparation of the recyclable activated material, urea is replaced with ammonia in step (1), and the product obtained is F-doped. h -BN / WS2 / Fe3O4.

[0062] The above F doping h -BN / WS2 / Fe3O4 was used as a recyclable activating material to leach uranium from argillaceous sandstone uranium ore according to the method in Example 1. The results showed that the uranium content in the leaching residue was 0.011%.

[0063] Comparative Example 3 This comparative example is basically the same as Example 1, except that in this comparative example, sodium fluoride aqueous solution is not added in step (1) when preparing the recyclable activated material, and the product obtained is O-doped. h -BN / WS2 / Fe3O4.

[0064] The above O doping h -BN / WS2 / Fe3O4 was used as a recyclable activating material to leach uranium from argillaceous sandstone uranium ore according to the method in Example 1. The results showed that the uranium content in the leaching residue was 0.008%.

[0065] As can be seen from the data of Example 1 and Comparative Examples 1-3 above, the effect of doping with only F or O is lower than that of Example 1. However, omitting both F and O doping will result in a significantly lower effect than that of Example 1. Furthermore, the uranium leaching content of the leaching residue is significantly greater than the increase in Comparative Examples 1 and 2 compared to Example 1, proving that F doping and O doping have a synergistic effect.

[0066] Comparative Example 4 This comparative example is basically the same as Example 1, except that WS2 is not added in step (1) when preparing the recyclable activated material, and the product obtained is F / O co-doped. h -BN / Fe3O4.

[0067] The above F / O co-doping h -BN / Fe3O4 was used as a recyclable activating material to leach uranium from argillaceous sandstone uranium ore according to the method in Example 1. The results showed that the uranium content in the leaching residue was 0.010%.

[0068] The data from Comparative Example 4 shows that omitting WS2 causes the system to be unable to communicate with... h -BN forms a heterojunction, which reduces the catalytic oxidation efficiency and significantly increases the uranium content in the leaching residue compared to Example 1.

[0069] Comparative Example 5 This comparative example is basically the same as Example 1, except that in the uranium leaching experiment, the spiral catalytic reaction device 100 used only has a threaded tube, and the threaded tube does not have a herringbone protrusion 111 and a threaded groove 112. The results show that the uranium content in the leaching residue is 0.15%.

[0070] Comparative Example 6 This comparative example is basically the same as Example 1, except that the spiral catalytic reaction device 100 used in the uranium leaching experiment has a threaded tube. The threaded tube is only provided with a herringbone-shaped protrusion 111 and no threaded groove 112. The results show that the uranium content in the leaching residue is 0.11%.

[0071] Comparative Example 7 This comparative example is basically the same as Example 1, except that the spiral catalytic reaction device 100 used in the uranium leaching experiment has a threaded tube, and only the threaded groove 112 is provided in the threaded tube, without the "human" shaped protrusion 111. The results show that the uranium content in the leaching residue is 0.009%.

[0072] The data from Comparative Examples 5-7 show that the placement of the "human" shaped protrusion 111 and the threaded groove 112 has a synergistic effect on the uranium content in the leaching residue.

[0073] Comparative Example 8 This comparative example is essentially the same as Example 1, except that the spiral catalytic reactor 100 used in the uranium leaching experiment has a threaded tube with annular protrusions and annular grooves inside. The height of the annular protrusions is 0.4 cm, and the depth of the annular grooves is 0.5 cm. The axial spacing between the annular protrusions and the annular grooves is 10 cm. Multiple annular protrusions and annular grooves are arranged alternately. The results show that the uranium content in the leaching residue is 0.012%.

[0074] As can be seen from the data of Comparative Example 8, even though protrusions and grooves are provided inside the threaded pipe, the protrusions in this comparative example are annular protrusions rather than herringbone protrusions. This results in a significantly lower effect on turbulence, secondary circulation, and near-wall shear force generated by high-viscosity slurry compared to Example 1. Consequently, the uranium content in the leaching residue in this comparative example is significantly increased compared to Example 1.

[0075] In summary, the method for preparing recyclable activated materials provided by this invention utilizes the co-doping of F and O elements. h -BN significantly disrupts h The lattice symmetry of -BN greatly enhances the piezoelectric response of the material under weak mechanical forces, thereby efficiently activating H2O2 to generate reactive oxygen free radicals. These free radicals can penetrate deep into the pores and surface of clay minerals, efficiently oxidizing adsorbed and encapsulated U(IV) to soluble U(VI), achieving "chemical dissociation" at the source. WS2 and Fe3O4 serve as supports; Fe3O4 imparts magnetic recyclability to the material, allowing for magnetic recovery after subsequent leaching, reducing catalyst usage costs. WS2 can also react with... h -BN forms heterojunctions, effectively promoting the separation of piezoelectric charges and further synergistically improving catalytic oxidation efficiency. The prepared recyclable activated material has good catalytic performance and can be widely used in the preparation of catalysts for uranium leaching from argillaceous sandstone uranium ore. Correspondingly, the leaching method for argillaceous sandstone uranium ore based on recyclable activated material provided by this invention uses the above-mentioned recyclable activated material as a catalyst, and is also equipped with a spiral catalytic reaction device 100. This spiral catalytic reaction device 100, by setting alternating protrusions 111 and threaded grooves 112, can generate strong turbulence, secondary circulation, and near-wall shear force for high-viscosity slurries. This design cleverly concentrates the mechanical energy of the slurry flow into continuous and strong stress, efficiently stimulating the catalytic activity of the piezoelectric material, alleviating the adsorption and encapsulation effect of clay minerals on uranium, and effectively preventing blockage caused by clay minerals, ensuring the adaptability of the process in complex ore bodies.

[0076] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a recyclable activated material, characterized in that, It includes: S1. Add WS2 and Fe3O4 into an aqueous solution. After stirring evenly, add a boron-containing compound, an aqueous solution of a fluorine precursor, and a nitrogen-oxygen-containing compound, and obtain a homogeneous suspension through stirring; S2. The homogeneous suspension is heated and stirred to react, then filtered, washed, and dried to obtain F / O co-doped solution. h -BN / WS2 / Fe3O4 precursor; S3, The F / O co-doping is performed. h The -BN / WS2 / Fe3O4 precursor was calcined under a protective atmosphere to obtain F / O co-doped material. h -BN / WS2 / Fe3O4, as a recyclable activation material.

2. The method for preparing recyclable activated materials according to claim 1, characterized in that, Based on the volume of the aqueous solution being 50 mL, the addition amount of the WS2 is 0.5 - 1.5 g; And / or, the addition amount of the Fe3O4 is 0.1 - 1.0 g; And / or, the addition amount of the boron-containing compound is 0.01 - 1.0 g; And / or, the addition amount of the aqueous solution of the fluorine precursor is 0.01 - 1 mL, and the concentration of the aqueous solution of the fluorine precursor is 0.01 - 0.05 mol / L; And / or, the addition amount of the nitrogen-oxygen-containing compound is 0.1 - 10 g.

3. The method for preparing recyclable activated materials according to claim 1, characterized in that, The boron-containing compound includes boric acid; And / or, the aqueous solution of the fluorine precursor includes at least one of ammonium fluoride and sodium fluoride; And / or, the nitrogen-oxygen-containing compound includes urea.

4. The method for preparing recyclable activated materials according to claim 1, characterized in that, The temperature of the stirring reaction is 60 - 95 °C, and the time is 4 - 12 h; And / or, the temperature of the calcination is 600 - 1200 °C, and the time is 3 - 10 h.

5. A recyclable activated material, characterized in that, It is prepared by using the preparation method of the recyclable activation material described in any one of claims 1 - 4.

6. A leaching method for uranium ore from argillaceous sandstone based on recyclable activated materials, characterized in that, It includes placing the recyclable activation material described in claim 5 into a pelitic sandstone uranium ore pulp, adding a H2O2 solution to obtain a mixture, placing the mixture into a spiral catalytic reaction device, and after multiple catalytic cycle reactions, performing solid-liquid separation to obtain a leaching solution and a leaching residue; wherein, the spiral catalytic reaction device is provided with a spiral tube, and the inner wall of the spiral tube is provided with protrusions and thread grooves, and both the protrusions and the thread grooves are multiple and arranged alternately.

7. The leaching method for uranium ore from argillaceous sandstone based on recyclable activated materials according to claim 6, characterized in that, The diameter of the spiral tube is 2 - 3 cm, the height of the protrusions is 0.3 - 0.5 cm, and the depth of the thread grooves is 0.4 - 0.6 cm; And / or, the axial distance between the protrusions is 8 - 12 cm; And / or, the pitch of the thread grooves is 8 - 12 cm.

8. The leaching method for uranium ore from argillaceous sandstone based on recyclable activated materials according to claim 6, characterized in that, The protrusions include a first side wall and a second side wall forming a "V" shape. The top ends of the first side wall and the second side wall are connected to form the tip of the protrusion. The bottom end of the first side wall is connected to the inner wall of the spiral tube, and the bottom end of the second side wall is connected to the inner wall of the spiral tube. The bottom ends of the first side wall and the second side wall are spaced apart; the included angle between the first side wall and the second side wall is 100 - 150°.

9. The leaching method for uranium ore from argillaceous sandstone based on recyclable activated materials according to claim 6, characterized in that, The solid-liquid ratio of the recyclable activation material, the pelitic sandstone uranium ore pulp, and the H2O2 solution is 120 - 180 mg:100 mL:1.2 - 1.8 mL. Among them, the concentration of the pelitic sandstone uranium ore pulp is 8 - 12 g / L, and the concentration of the H2O2 solution is 0.4 - 10. An apparatus for implementing the leaching method for uranium ore from argillaceous sandstone based on recyclable activated materials as described in any one of claims 6-9, characterized in that, ​

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