Method for separating and recovering uranium and molybdenum in complex uranium-molybdenum ore

Abstract

This application provides a comprehensive recovery method for complex uranium-molybdenum ores. The method includes: radioactive beneficiation of the complex uranium-molybdenum ores to obtain radioactive and non-radioactive ores; first flotation of the radioactive ores to obtain first sulfide and oxide ores; second flotation of the non-radioactive ores to obtain second sulfide ores; and conversion leaching and extraction of the oxide ores, as well as the first and / or second sulfide ores, to obtain uranium and molybdenum products. A first mother liquor generated during the molybdenum product preparation process is returned to a third leaching step of the oxide ores; and a second mother liquor generated during the uranium product preparation process is returned to a uranium extraction step. By using radioactive beneficiation, flotation, conversion leaching, and extraction, the method solves the problems of high residual acidity in the conversion leaching solutions of the first sulfide, oxide, and second sulfide ores, making extraction and recovery difficult and establishing separation points challenging.

Description

Technical Field

[0001] This application relates to the field of uranium-molybdenum recovery technology, and in particular to a method for separating and recovering uranium-molybdenum from complex uranium-molybdenum mines. Background Technology

[0002] Uranium and molybdenum are important resources. Due to their similar chemical properties, they often occur together. Their separation is challenging because of these similarities. Currently, the separation method for uranium oxide-type uranium-molybdenum ores involves crushing and grinding the ore, followed by sulfuric acid leaching. The leachate is then extracted with amine extractants, typically in steps. The organic phases supporting molybdenum and molybdenum are back-extracted to obtain a back-extract, which is then separately precipitated to prepare uranium and molybdenum products. Molybdenum sulfide concentrates are mostly pyrometallurgically processed, while uranium is primarily recovered using hydrometallurgical processes.

[0003] Existing methods for separating and recovering uranium and molybdenum are mainly designed for single minerals. For complex ores containing two or more elements such as uranium and molybdenum, current processing methods generate large amounts of waste acid, and the extraction and recovery of molybdenum and uranium are also quite difficult under high acidity conditions.

[0004] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of protection of this application. Summary of the Invention

[0005] This application provides a comprehensive recovery method for complex uranium-molybdenum ores to solve or alleviate one or more of the technical problems mentioned above.

[0006] This application provides a method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores. The method includes: radioactive beneficiation of the complex uranium-molybdenum ores to obtain radioactive and non-radioactive ores; first flotation of the radioactive ores to obtain first sulfide and oxide ores; second flotation of the non-radioactive ores to obtain second sulfide ores; conversion leaching and extraction of the oxide ores, as well as the first and / or second sulfide ores, to obtain uranium and molybdenum products. Specifically, a first mother liquor generated during the molybdenum product preparation process is returned to a third leaching step of the oxide ores; a second mother liquor generated during the uranium product preparation process is returned to a uranium extraction step; and a first leachate generated during the conversion leaching of the first sulfide ores and / or a second leachate generated during the conversion leaching of the second sulfide ores are used as a third leachate for conversion leaching of the oxide ores.

[0007] The method for separating and recovering uranium and molybdenum in complex uranium-molybdenum ores according to embodiments of this application achieves the recovery of molybdenum and uranium in complex molybdenum-uranium ores containing oxide and sulfide ores, and obtains molybdenum and uranium products. By employing conversion leaching and extraction, the method solves the problems of high residual acidity in the conversion leaching solutions of the first sulfide ore, oxide ore, and second sulfide ore, which hinders extraction and recovery, and identifies separation points. Attached Figure Description

[0008] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0009] Figure 1 These are schematic diagrams of the process for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to some embodiments; Figure 2 These are schematic diagrams of the mineral processing and blending processes in some embodiments; Figure 3 These are schematic diagrams of the conversion leaching process in some embodiments; Figure 4 These are schematic diagrams of the extraction process in some embodiments. Detailed Implementation

[0010] The embodiments of this application are described in detail below. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0011] It should be noted that the terms "first," "second," etc., used in this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0012] In this application, when numerical intervals (i.e., numerical ranges) are involved, unless otherwise specified, the distribution of selectable numerical values ​​within the numerical interval is considered continuous, and includes the two endpoints of the numerical interval (i.e., the minimum and maximum values), as well as every numerical value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that numerical interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints, which is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical ranges disclosed in this application should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. The term "numerical interval" can be broadly included to include percentage intervals, ratio intervals, proportion intervals, etc.

[0013] This application provides a method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores. (Reference) Figure 1 The method includes: (1) performing radioactive beneficiation on complex uranium-molybdenum ore to obtain radioactive and non-radioactive ore; (2) performing a first flotation on the radioactive ore to obtain a first sulfide ore and an oxide ore; (3) performing a second flotation on the non-radioactive ore to obtain a second sulfide ore; and (4) performing conversion leaching and extraction on the oxide ore, as well as on the first sulfide ore and / or the second sulfide ore, to obtain uranium products and molybdenum products, wherein a first mother liquor generated during the preparation of the molybdenum products is returned to a third leaching step of the oxide ore; a second mother liquor generated during the preparation of the uranium products is returned to a uranium extraction step; and a first leaching solution generated during the conversion leaching of the first sulfide ore and / or a second leaching solution generated during the conversion leaching of the second sulfide ore are used as a third leaching solution for conversion leaching of the oxide ore.

[0014] The method for separating and recovering uranium and molybdenum in complex uranium-molybdenum ores according to embodiments of this application achieves the recovery of molybdenum and uranium in complex molybdenum-uranium ores containing oxide and sulfide ores, and obtains molybdenum and uranium products. By employing conversion leaching and extraction, the method solves the problems of high residual acidity in the conversion leaching solutions of the first sulfide ore, oxide ore, and second sulfide ore, which hinders extraction and recovery, and identifies separation points.

[0015] According to an embodiment of this application, the conversion leaching includes: performing a first leaching on the first sulfide ore to obtain a first leachate and a first molybdenum-containing slag; performing a second leaching on the second sulfide ore to obtain a second leachate and a second molybdenum-containing slag; performing a third leaching on the oxide ore to obtain a third leachate and leaching residue, the third leachate comprising the first leachate, acid, and optionally a second leachate; separating molybdenum and uranium from the third leachate to obtain uranium products and a molybdenum organic phase; purifying the first molybdenum-containing slag and the second molybdenum-containing slag to obtain ammonium molybdate and a first mother liquor, wherein the first mother liquor is returned to the third leachate for the raw materials of the separation, and the molybdenum extract is returned to the purification treatment to extract molybdenum from the molybdenum extract.

[0016] According to an embodiment of this application, performing a first flotation on the radioactive ore to obtain a first sulfide ore and an oxide ore includes: performing a first flotation on the radioactive ore to obtain a first sulfide ore and an intermediate oxide ore, and performing a first blending treatment on the intermediate oxide ore to obtain an oxide ore.

[0017] According to an embodiment of this application, after the second flotation and before obtaining the second sulfide ore, the method further includes: performing a second blending treatment on the product obtained from the second flotation.

[0018] According to the embodiments of this application, refer to Figures 2-4 A method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores includes: radioactive beneficiation of the complex uranium-molybdenum ores to obtain radioactive and non-radioactive ores; first flotation of the radioactive ores to obtain first sulfide ores and intermediate oxide ores; first blending of the intermediate oxide ores to obtain oxide ores; second flotation and second blending of the non-radioactive ores to obtain second sulfide ores; first leaching of the first sulfide ores to obtain first leachate and first molybdenum-bearing slag; and second leaching of the second sulfide ores to obtain... A second leaching solution and a second molybdenum-containing slag are applied; the oxidized ore is then subjected to a third leaching to obtain a third leaching solution and leaching residue. The third leaching solution comprises the first leaching solution, the second leaching solution, and acid. Molybdenum and uranium are separated from the third leaching solution to obtain uranium products and a molybdenum organic phase. The first and second molybdenum-containing slags are purified to obtain ammonium molybdate and a first mother liquor, wherein the first mother liquor is returned to the third leaching solution as raw material for the separation, and the molybdenum extract is returned to the purification treatment to extract molybdenum from the molybdenum extract. This achieves the recovery of uranium and molybdenum from complex uranium-molybdenum ores, solving the problem of high residual acid in sulfide ore conversion leaching solutions, which makes extraction, recovery, and separation difficult.

[0019] Specifically, through radioactive beneficiation, first flotation, second flotation, first blending, and second blending, complex uranium-molybdenum ores are separated into primary sulfide ores, secondary sulfide ores, and oxide ores. Radioactive beneficiation can pre-select uranium-free ores. Blending can process not only ores from our own mines but also flexibly process purchased oxide ores or molybdenum sulfide concentrates. When the market changes, the blending ratio can be adjusted to maintain production stability and economic efficiency, enhancing the process's resilience. Pressure leaching of primary and secondary sulfide ores produces leachates (first and second leachates), which are used as leaching agents for oxide ores. This not only saves on oxidant leaching costs but also reduces the expenses for treating the first and second leachates. The first mother liquor generated during the treatment of the first and second molybdenum-containing slags is returned to the extraction system as raw material, reducing emissions during the extraction and separation of molybdenum and uranium, thus improving uranium recovery and reducing pollution.

[0020] According to embodiments of this application, complex uranium-molybdenum ore is subjected to radioactive beneficiation to obtain radioactive and non-radioactive ore. In this step, the complex uranium-molybdenum ore comprises oxide and sulfide ores. Radioactive beneficiation of the complex uranium-molybdenum ore separates the uranium-bearing ore. By using radioactive beneficiation ore or blending, the uranium-bearing and non-uranium-bearing ore are recovered separately, improving the uranium recovery rate.

[0021] In some embodiments, the radioactive beneficiation involves breaking down complex uranium-molybdenum ore and then entering a radioactive beneficiation area equipped with radioactive sensors to detect the radioactivity of the broken ore, thereby differentiating uranium-bearing grades and achieving radioactive beneficiation.

[0022] Furthermore, the radioactive beneficiation boundary condition is that the radioactivity meets the range of 0.1 bq / g to 10 bq / g. Radioactivity refers to the number of atomic nuclei that decay from a radioactive source per unit time. Higher radioactivity indicates higher radiation intensity. This application sets the radioactive beneficiation boundary condition to 0.1 bq / g to 10 bq / g, which allows for the selection of uranium-bearing ores with extremely low grades, maximizing the recovery of uranium resources, and controlling the cost of subsequent processing to avoid the phenomenon where the cost of extracting uranium exceeds the cost of the uranium product itself.

[0023] According to an embodiment of this application, a radioactive ore is subjected to a first flotation to obtain a first sulfide ore (ore S1) and an intermediate oxide ore, and the intermediate oxide ore is subjected to a first blending treatment to obtain an oxide ore (ore O).

[0024] In some embodiments, the first flotation involves adding a first flotation reagent in a neutral or weakly alkaline environment to float the first sulfide ore, thereby distinguishing it from intermediate oxide ore. Prior to the first flotation, the radioactive ore needs to be ground to control its particle size to -150 mesh to -350 mesh, preferably -200 mesh.

[0025] Furthermore, the first flotation stage employs fatty acid collectors such as sodium oleate and oxidized paraffin soap to collect molybdenum oxide minerals and partially oxidized molybdenum sulfide minerals, achieving mixed flotation of oxygen and sulfur minerals and thus ensuring the overall recovery rate of the entire flotation process. The proportion of molybdenum sulfide in the intermediate oxidized ore obtained after the first flotation stage is ≤20%.

[0026] In some embodiments, the ore used in the first blending process is uranium ore or uranium-molybdenum ore, wherein the uranium grade is not less than 0.03%, the molybdenum grade is not less than 0.1%, and the ore must be an oxidizing ore with a molybdenum sulfide content not exceeding 20%. Thus, the first blending process causes the intermediate oxidizing ore to form an oxidizing ore.

[0027] According to an embodiment of this application, the non-radioactive ore is subjected to a second flotation and a second blending process to obtain a second sulfide ore (ore S2).

[0028] In some embodiments, the second flotation involves adding a second flotation reagent in a neutral or weakly alkaline environment to float the first sulfide ore to distinguish it from the second sulfide ore. Prior to the second flotation, the non-radioactive ore is ground to a particle size of (-150) mesh to (-350) mesh, preferably -200 mesh.

[0029] Furthermore, the second flotation process includes roughing and cleaning. First, fatty acid collectors such as sodium oleate and oxidized paraffin soap are used to collect molybdenum oxide minerals and partially oxidized molybdenum sulfide minerals, achieving mixed flotation of oxygen and sulfur minerals and thus ensuring the overall recovery rate of the entire flotation process. Second, hydrocarbon oils and xanthate-based sulfide mineral collectors are used to preferentially float sulfide minerals with better crystal structures and higher floatability in complex ores, yielding higher-grade concentrates.

[0030] The tailings from the second flotation stage can be either sent to the first flotation stage or disposed of directly, depending on economic considerations. Generally, it is recommended to send the finely treated tailings to the first flotation stage.

[0031] In some embodiments, the ore used in the second blending process is molybdenum sulfide ore with a molybdenum grade of not less than 20% and a molybdenum oxide content of not more than 20%. After blending, the radioactivity of the second sulfide ore is 0.1 Bq / g to 5 Bq / g.

[0032] According to an embodiment of this application, the first sulfide ore is subjected to a first leaching to obtain a first leachate and a first molybdenum-containing slag. In this step, the first leaching of the first sulfide ore is pressure leaching, which yields the first molybdenum-containing slag and the first leachate, thus achieving preliminary treatment of the first sulfide ore.

[0033] In some embodiments, the first leaching is carried out under pressure, wherein the oxygen pressure P and the air partial pressure P0 are... 1、 The relationship between the water vapor pressure P2 and the working pressure P0 of the pressurized vessel is P + P2 + P1 ≦ P0, where P0 = 0.5 MPa ~ 5 MPa. Therefore, by maximizing the oxygen partial pressure within the equipment's safety limits, the efficient conversion of molybdenum sulfide is ensured; molybdenum enters the solid phase and uranium enters the liquid phase, simplifying subsequent separation processes.

[0034] Furthermore, In some embodiments, the temperature of the first leaching is 120°C-200°C, such as 120°C, 130°C, 140°C, 150°C, 180°C, 200°C, etc.

[0035] In some embodiments, the liquid-to-solid ratio of the first leaching is 1 / 5 to 1 / 15, such as 1 / 5, 1 / 7, 1 / 9, 1 / 10, 1 / 15, etc.

[0036] In some embodiments, the acidity of the first leachate is 80 g / L-200 g / L, such as 80 g / L, 100 g / L, 120 g / L, 150 g / L, 180 g / L, or 200 g / L. After pressurized oxygen conversion, the sulfur in the second sulfide ore is oxidized to sulfuric acid, which enters the liquid phase L1 with an acidity as high as 80 g / L-200 g / L. This high-acid solution is directly used as a leaching agent to treat the oxidized ore, replacing the need for purchased fresh sulfur in traditional processes.

[0037] In some embodiments, the molybdenum content in the first molybdenum-containing slag is 20wt%-50wt%. Lower molybdenum content results in more residue after ammonia dissolution during subsequent recovery, increasing the filtration load. A molybdenum content of 20wt% to 50wt% keeps the slag volume within an acceptable range.

[0038] According to an embodiment of this application, the second sulfide ore is subjected to a second leaching to obtain a second leachate and a second molybdenum-containing slag. In this step, the second leaching of the second sulfide ore is performed under pressure, which yields a second molybdenum-containing slag and a second leachate, thus achieving preliminary treatment of the second sulfide ore.

[0039] In some embodiments, the second leaching is carried out under pressure, wherein the oxygen pressure P and the air partial pressure P0 are respectively... 1、The relationship between the water vapor pressure P2 and the working pressure P0 of the pressurized vessel is P + P2 + P1 ≦ P0, where P0 = 0.5 MPa ~ 5 MPa. Therefore, by maximizing the oxygen partial pressure within the equipment's safety limits, the efficient conversion of molybdenum sulfide is ensured; molybdenum enters the solid phase and uranium enters the liquid phase, simplifying subsequent separation processes.

[0040] In some embodiments, the temperature of the second leaching is 120°C-200°C, such as 120°C, 130°C, 140°C, 150°C, 180°C, 200°C, etc.

[0041] In some embodiments, the liquid-to-solid ratio of the second leaching is 1 / 5 to 1 / 15, such as 1 / 5, 1 / 7, 1 / 9, 1 / 10, 1 / 15, etc.

[0042] In some embodiments, the acidity of the second leachate is 80 g / L-200 g / L, such as 80 g / L, 100 g / L, 120 g / L, 150 g / L, 180 g / L, or 200 g / L. After pressurized oxygen conversion, the sulfur in the second sulfide ore is oxidized to sulfuric acid and enters the liquid phase L1, with an acidity as high as 80-200 g / L. This high-acid solution is directly used as a leaching agent to treat the oxidized ore, replacing the need for purchased fresh sulfur in traditional processes.

[0043] In some embodiments, the molybdenum content in the second molybdenum-containing slag is 20wt%-50wt%. Lower molybdenum content results in more residue after ammonia dissolution during subsequent recovery, increasing the filtration load. A molybdenum content of 20wt% to 50wt% keeps the slag volume within an acceptable range.

[0044] According to an embodiment of this application, the oxidized ore undergoes a third leaching to obtain a third leaching solution and leaching residue. The third leaching solution comprises the first leaching solution, the second leaching solution, and an acid. In this step, the leaching agent for the oxidized ore is the first and second leaching solutions, which reduces the utilization of leaching solutions and allows for their efficient use. The obtained third leaching solution is used for subsequent uranium and molybdenum extraction.

[0045] In some embodiments, the acidity of the third leachate is 20 g / L-60 g / L. The lower limit of the acidity of the third leachate (20 g / L) has entered the suitable range for molybdenum extraction. It can be used directly or after slight adjustment for molybdenum extraction without the need to add a large amount of acid or alkali for pH adjustment, thus saving reagent consumption. The amine extractant (N235) can achieve an extraction rate of more than 95% for molybdenum at an acidity of 20 g / L-40 g / L.

[0046] Understandably, processing molybdenum oxide and sulfide ores separately improves molybdenum recovery and process adaptability. The primary sulfide, secondary sulfide, and oxide ores are comprehensively utilized; the sulfur in the primary and secondary sulfide ores is converted into sulfuric acid for oxidizing the ores. This reduces both sulfuric acid consumption and sulfur dioxide emissions into the air.

[0047] According to an embodiment of this application, the third leachate is used to separate molybdenum and uranium to obtain uranium products and a molybdenum organic phase.

[0048] In some embodiments, the separation includes the following steps: mixing the third leachate, the first mother liquor, and the first conditioning agent to obtain an extract; adding a second conditioning agent to the extract, followed by molybdenum extraction and washing to obtain a molybdenum organic phase and a molybdenum raffinate; adding a third conditioning agent to the molybdenum raffinate to form a uranium extraction stock solution, and performing uranium extraction on the uranium extraction stock solution to obtain a uranium extract and a uranium raffinate; performing uranium back-extraction on the uranium extract to obtain a uranium precipitate and a regenerated uranium extractant, wherein the regenerated uranium extractant (extractant 2) is returned to the uranium extraction; and performing a first solid-liquid separation on the uranium precipitate to obtain a uranium product and a second mother liquor, wherein the second mother liquor is returned to the uranium extraction stock solution as a raw material for the uranium extraction.

[0049] By controlling the acidity of the third leaching solution, uranium and molybdenum are separated. The closed-loop circulation system returns the first mother liquor to the extract and the second mother liquor to the uranium extraction solution, achieving the most complete recovery of valuable elements, with only one discharge outlet for the uranium extraction residue. Molybdenum enters the subsequent ammonium molybdate preparation in the form of an organic phase, while uranium is used as the final product in the form of sodium diuranate / ammonium diuranate.

[0050] In some embodiments, the molybdenum organic phase undergoes molybdenum back-extraction to obtain a molybdenum back-extraction solution and a regenerated molybdenum extractant (extractant 1), which is then returned to the molybdenum extraction. The molybdenum extractant is recycled during both the molybdenum extraction and back-extraction processes, significantly reducing reagent costs. The molybdenum back-extraction solution enters the product, and the first mother liquor formed by the molybdenum precipitation is returned to the extract, forming a closed loop, improving recovery and reducing pollution.

[0051] Furthermore, ammonia was selected as the molybdenum extractant, as ammonia has a better extraction effect on molybdenum.

[0052] Furthermore, the uranium extractant includes an extractant, a diluent, and a phase modifier. The extractant includes N235, the diluent includes sulfonated kerosene, and the phase modifier includes at least one of octanol, mixed alcohols, TBP, etc.

[0053] In some embodiments, the redox potential of the extract is E4, and the acidity is CH4, wherein E4 is 300-600 mV, and CH4 is 20 g / L-40 g / L. The acidity ensures that molybdenum is [MoO2(SO4)2]².- The presence of molybdenum in its complexed anionic form, coupled with the potential ensuring its hexavalent oxidation state, places molybdenum in a state most readily extractable by N235. Acidity is selected within the non-optimal extraction range for uranium (the optimal acidity for uranium is 10-30 g / L), while the potential ensures uranium exists as U(VI) but is not extracted, achieving a separation effect where molybdenum is preferentially extracted while uranium remains in the aqueous phase.

[0054] In some embodiments, the acidity of the uranium extraction solution is 10 g / L-30 g / L.

[0055] In some embodiments, after the first solid-liquid separation and before obtaining the uranium product, the first solid-liquid separation product is dried.

[0056] According to an embodiment of this application, the first molybdenum-containing slag and the second molybdenum-containing slag are purified to obtain ammonium molybdate and a first mother liquor.

[0057] In some embodiments, the purification process includes: using an alkaline solution to react a first molybdenum-containing slag and a second molybdenum-containing slag solution to obtain a solution; performing impurity removal and a second solid-liquid separation on the solution to obtain ammonium molybdate and a first mother liquor; wherein the molybdenum back-extraction solution is returned to the solution as the raw material for impurity removal. The purification process of the first and second molybdenum-containing slags achieves a total molybdenum recovery rate greater than 95%; the return of the molybdenum back-extraction solution to the solution simplifies the process, reduces emissions, and improves molybdenum recovery efficiency.

[0058] In some embodiments, after the second solid-liquid separation and before obtaining ammonium molybdate, the method further includes drying the second solid-liquid separation product.

[0059] Understandably, uranium-free molybdenum and uranium-containing molybdenum are processed separately and then collected to obtain ammonium molybdate. The intermediate products, the first and second molybdenum-containing slags, are marketable, ensuring the flexibility of the process.

[0060] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. It should be understood that these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0061] Example 1 A complex uranium-molybdenum ore contains molybdenum sulfide, molybdenum oxide, and uranium. The uranium grades in the raw ore are 0.24%, 0.03%, and 0.037%, respectively. 6040 kt of the raw ore underwent radioactive beneficiation, with a cutoff grade of C0 = 0.5 Bq / g, yielding 17% radioactive ore and decontaminated ore (non-radioactive ore). These were then ground, flotated, and blended separately, resulting in radioactive oxide ore O, radioactive sulfide concentrate S1, and non-radioactive sulfide concentrate S2. Ore O has uranium and molybdenum grades of 0.1% and 0.2%, respectively; S1 has uranium and molybdenum grades of 0.5% and 35%, respectively; and S2 has a molybdenum grade of 48%. A total of 1000 kt of ore O (containing 1 kt of uranium and 2 kt of molybdenum) and 100 kt of ore S1 (containing 0.5 kt of uranium and 35 kt of molybdenum) were extracted. Several tons of ore S2 were sold to a pyrometallurgical plant.

[0062] Ore S1 was subjected to pressurized oxygen conversion. Water, residual sulfuric acid, and ore S1 were added to a pressurized reactor at a liquid-to-solid ratio of 10 / 1 and a temperature of 180°C. Oxygen was added and stirred, and the oxygen pressure was adjusted to control the total pressure (working pressure of the pressurized reactor) at 1.8 MPa to 2.0 MPa. After the reaction, the solid and liquid were discharged and solid-liquid separation was performed to obtain the first leachate (L1) (containing 157 g / L sulfuric acid, 0.5 g / L uranium, and 7 g / L molybdenum) and molybdenum oxide M1 (the first molybdenum-containing slag).

[0063] M1 is dissolved in ammonia water, filtered to remove residue, and the resulting solution L10 is combined with the molybdenum back-extraction solution L9. A purification reagent is added, followed by sulfuric acid to adjust the acidity and precipitate. Solid-liquid separation yields the first mother liquor L11 and ammonium molybdate product M3.

[0064] Oxide-type uranium-molybdenum ore O was leached with conversion solution L1 and 50% water added, maintaining a liquid-to-solid ratio of 1.5 L / kg. After solid-liquid separation, the leachate was obtained. The third leachate, L3, contained 36 g / L sulfuric acid, 6 g / L molybdenum, and 1 g / L uranium. L3 was mixed with L11, and the wash water was combined. The mixture was then adjusted with hydrogen peroxide to obtain L4 (extract), with a potential of 500 mV and an acidity of 28 g / L. Multi-stage countercurrent extraction was performed using 7.5 vol% N235-mixed alcohol-kerosene as the extractant. The loaded organic phase was washed in the tank, and the molybdenum organic phase was back-extracted with ammonia water to obtain molybdenum back-extract L9.

[0065] The molybdenum extraction residue L5 and the second mother liquor L8 were combined and adjusted. The acidity of the extraction solution was 20 g / L. Eight-stage countercurrent extraction was performed using 7.5 vol% N235-mixed alcohol-kerosene as the extractant. Sodium carbonate was used for uranium back-extraction. Sodium diuranate was prepared by adding caustic soda to the uranium back-extraction solution and filtering to obtain the second mother liquor L8 and uranium product U1.

[0066] Example 2 A complex uranium-molybdenum ore contains molybdenum sulfide, molybdenum oxide, and uranium, with grades of 0.24%, 0.03%, and 0.037% respectively in the raw ore. 6040 kt of the raw ore underwent radioactive beneficiation, with a cutoff grade of C0 = 0.5 Bq / g, yielding 17% radioactive ore. The radioactive ore and deregulated ore (non-radioactive ore) were then further processed by grinding and flotation. This yielded a radioactive oxide type ore O', a radioactive sulfide type concentrate S1, and a non-radioactive sulfide concentrate S2'. O' contained 0.1% and 0.2% uranium and molybdenum, respectively; S1 contained 0.5% and 35% uranium and molybdenum, respectively; and S2' contained 48% molybdenum. Concentrate S1 totaled 30 kt (containing 0.03 kt uranium and 10.5 kt molybdenum), yielding 1000 kt of O' (containing 1 kt uranium and 2 kt molybdenum). S2' totaled 10 kt. 5000t of tailings (molybdenum grade 0.01%, uranium grade 0.004%) were disposed of. The molybdenum recovery rate in the second beneficiation process was 90.6%, the total molybdenum recovery rate was 97%, and the total uranium recovery rate was 91%.

[0067] The ore with radioactivity ≤1 Bq / g and a grade similar to that of O' was purchased for blending and production. A total of 2000 kt of O' was obtained (containing 2 kt of uranium and 4 kt of molybdenum).

[0068] Molybdenum concentrate with radioactivity ≤1 Bq / g and a grade similar to S2' was purchased for blending and production. A total of 50 kt of S2 was obtained.

[0069] A total of 100 kt of S1 and S2 were obtained. Ore O totaled 1000 kt, with uranium and molybdenum grades of 0.1% and 0.1% respectively (containing 1 kt of uranium and 1 kt of molybdenum). S2 contained 50 kt of ore with a molybdenum grade of 40% (containing 20 kt of molybdenum).

[0070] Pressurized oxygen conversion was carried out on ores S1 and S2. Water, residual sulfuric acid, and ore S2 were added to the pressurized reactor at a liquid-to-solid ratio of 10 / 1, at a temperature of 200℃. Oxygen was added and stirred, and the oxygen pressure was adjusted to control the total pressure (working pressure of the pressurized reactor) at 1.8MPa~2.0MPa. After the reaction, the solid and liquid were discharged and separated to obtain a second leaching solution L2 (containing 180g / L sulfuric acid and 7g / L molybdenum) and molybdenum oxide M2 ​​(second molybdenum-containing slag). Molybdenum oxide M2 ​​was sold. The obtained M1 was subjected to alkali dissolution for further production.

[0071] Oxide-type uranium-molybdenum ore O was leached with conversion solution L2 and supplemented with liquid to maintain a liquid-to-solid ratio of 2 L / kg. After solid-liquid separation, the leachate was obtained. The third leachate L3 contained 38 g / L sulfuric acid, 4 g / L molybdenum, and 0.5 g / L uranium. The third leachate L3 was mixed with L11, and the wash water was combined. The mixture was then adjusted with hydrogen peroxide and calcium hydroxide to obtain L4 (extract), with a potential of 500 mV and an acidity of 28 g / L. Multi-stage countercurrent extraction was performed using 10 vol% N235-mixed alcohol-kerosene as the extractant. The loaded organic phase was washed in the tank, and the molybdenum organic phase was back-extracted with ammonia water to obtain molybdenum back-extract L9.

[0072] The molybdenum back-extraction solutions L9 were combined, and a purification reagent was added, followed by the addition of sulfuric acid to adjust the acidity and precipitate. Solid-liquid separation was performed to obtain the first mother liquor L11 and the ammonium molybdate product M3.

[0073] The residual water from the molybdenum extraction, L5, was combined and adjusted with the uranium mother liquor, L8. The acidity of the extraction solution was 20 g / L. Multi-stage countercurrent extraction was performed using 7.5% N235-mixed alcohol-kerosene as the extractant. Sodium carbonate was used for back-extraction. Sodium diuranate was prepared by adding caustic soda to the back-extraction solution. After filtration, mother liquor L8 and uranium product U1 were obtained.

[0074] Example 3 A complex uranium-molybdenum ore contains molybdenum sulfide, molybdenum oxide, and uranium, with grades of 0.12%, 0.005%, and 0.012%, respectively. 21,053 kt of the raw ore underwent radioactive beneficiation, with a cutoff grade of C0 = 1 Bq / g, yielding 4.7% radioactive ore. Radioactive and deregulated (non-radioactive) ores were then obtained, followed by grinding, flotation, and blending. This yielded radioactive oxide ore O, radioactive sulfide concentrate S1, and non-radioactive sulfide concentrate S2'. Ore O contained 0.1% uranium and 0.1% molybdenum, S1 contained 1.5% uranium and 20% molybdenum, and S2 contained 48% molybdenum. A total of 1000 kt of ore O (containing 1 kt of uranium and 1 kt of molybdenum) and 4 kt of concentrate S1 (containing 0.06 kt of uranium and 0.8 kt of molybdenum) were obtained, and 50 kt of S2' were sold to a pyrometallurgical plant. 20,000 tons of tailings (0.01% molybdenum, 0.002% uranium) were disposed of. The molybdenum recovery rate of beneficiation 2 was 92.3%, the total molybdenum recovery rate was 92.4%, and the total uranium recovery rate was 83%. A total of 4 kt of ore S1 was produced (containing 3.015 kt of molybdenum and 0.2 kt of uranium).

[0075] The S1 ore was subjected to pressurized oxygen conversion. Water, residual sulfuric acid, and S1 ore were added to the pressurized reactor at a liquid-to-solid ratio of 5:1 and a temperature of 150℃. Oxygen was added and stirred, and the oxygen pressure was adjusted to control the total pressure (working pressure of the pressurized reactor) at 1.8 MPa to 2.0 MPa. After the reaction, the solid and liquid were discharged and solid-liquid separation was performed to obtain the first leaching solution L1 (containing 175 g / L sulfuric acid, 3 g / L uranium, and 7 g / L molybdenum) and molybdenum oxide M1 (the first molybdenum-containing slag).

[0076] M1 is dissolved in ammonia water, filtered to remove residue, and the resulting solution L10 is combined with the molybdenum back-extraction solution L9. A purification reagent is added, followed by sulfuric acid to adjust the acidity and precipitate. Solid-liquid separation yields the first mother liquor L11 and ammonium molybdate product M3.

[0077] Oxide-type uranium-molybdenum ore O was leached with conversion solution L1 and supplemented with liquid to maintain a solid-liquid ratio of 2.5 L / kg. After solid-liquid separation, the leachate was obtained. The third leachate L3 contained sulfuric acid with a concentration of 48 g / L, molybdenum 3.9 g / L, and uranium 1.9 g / L. L3 was mixed with L11, and the wash water was combined. The mixture was then adjusted with hydrogen peroxide and calcium hydroxide to obtain L4 (extract), with a potential of 500 mV and an acidity of 28 g / L. Multi-stage countercurrent extraction was performed using 5 vol% N235-mixed alcohol-kerosene as the extractant. The loaded organic phase was washed in the tank, and the molybdenum organic phase was back-extracted with ammonia to obtain back-extract L9.

[0078] The molybdenum extraction residue L5 and the second mother liquor L8 were combined and adjusted. The acidity of the extraction solution was 20 g / L. Multi-stage countercurrent extraction was performed using 5% N235-mixed alcohol-kerosene as the extractant. Ammonium sulfate was used for back-extraction. Ammonia was added to the back-extraction solution to prepare ammonium diuranate. After filtration, L8 and uranium product U1 were obtained.

[0079] Example 4 A complex uranium-molybdenum ore underwent radioactive beneficiation with a cutoff grade of C0 = 6 Bq / g. This yielded radioactive ore and decontaminated ore (non-radioactive ore), which were then processed through grinding, flotation, and blending. The resulting ore was an oxide-type ore (O) and a sulfide-type concentrate (S1). O contained 0.2% uranium and 0.2% molybdenum, while S1 contained 0.2% uranium and 30% molybdenum. The total yield of O was 1000 kt (containing 2 kt of uranium and 2 kt of molybdenum), and the total yield of S1 was 100 kt (containing 0.2 kt of uranium and 30 kt of molybdenum).

[0080] Ore S1 was subjected to pressurized oxygen conversion. Water, residual sulfuric acid, and ore S1 were added to a pressurized reactor at a liquid-to-solid ratio of 5:1. The temperature was 150℃, oxygen was added and stirred, and the oxygen pressure was adjusted to control the total pressure (working pressure of the pressurized reactor) at 1.8MPa~2.0MPa. After the reaction, the solid and liquid were discharged and solid-liquid separation was performed to obtain the first leachate L1 (containing 177g / L sulfuric acid, 0.26g / L uranium, and 7g / L molybdenum) and molybdenum oxide M1.

[0081] M1 is dissolved in ammonia water, filtered to remove residue, and the resulting solution L10 is combined with the molybdenum back-extraction solution L9. A purification reagent is added, followed by sulfuric acid to adjust the acidity and precipitate. Solid-liquid separation yields mother liquor L11 and ammonium molybdate product M3.

[0082] Oxide-type uranium-molybdenum ore O was leached with conversion solution L1 and supplemented with liquid to maintain a solid-liquid ratio of 3 L / kg. The mixture was stirred and leached. After solid-liquid separation, a leachate L3 was obtained, containing 40 g / L sulfuric acid, 3.6 g / L molybdenum, and 0.78 g / L uranium. L3 was mixed with L11, and the wash water was combined. The mixture was then adjusted with hydrogen peroxide and calcium hydroxide to obtain L4, with a potential of 500 mV and an acidity of 28 g / L. Multi-stage countercurrent extraction was performed using 5% N235-mixed alcohol-kerosene as the extractant. The loaded organic phase was washed in the tank, and the molybdenum organic phase was back-extracted with ammonia water to obtain back-extract L9.

[0083] The residual water from the molybdenum extraction, L5, was combined and adjusted with the mother liquor of uranium, L8. The acidity of the extraction solution was 20 g / L. Multi-stage countercurrent extraction was performed using 5% N235-mixed alcohol-kerosene as the extractant. Ammonium sulfate was used for back-extraction. Ammonia was added to the back-extraction solution to prepare ammonium diuranate. After filtration, mother liquor L8 and uranium product U1 were obtained.

[0084] It should also be noted that the terms "some embodiments," "other embodiments," and "embodiments" used in this application refer to specific features, structures, or characteristics described in connection with those embodiments, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0085] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0086] It should also be noted that the above are merely preferred embodiments of this application and do not limit the scope of protection of this application. Any equivalent structural or procedural transformations made based on the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of protection of this application.

Claims

1. A method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores, characterized in that, Includes the following steps: Radioactive beneficiation is used to process complex uranium-molybdenum ores to obtain radioactive and non-radioactive minerals. The radioactive ore is subjected to a first flotation to obtain a first sulfide ore and an oxide ore; The non-radioactive ore is subjected to a second flotation to obtain a second sulfide ore. The oxide ore, as well as the first sulfide ore and / or the second sulfide ore, are subjected to conversion leaching and extraction to obtain uranium and molybdenum products. Specifically, the first mother liquor generated during the preparation of the molybdenum product is returned to the third leaching process of the oxide ore; the second mother liquor generated during the preparation of the uranium product is returned to the uranium extraction process; the first leaching solution generated during the first sulfide ore conversion leaching process and / or the second leaching solution generated during the second sulfide ore conversion leaching process are used as the third leaching solution for conversion leaching of the oxide ore.

2. The method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to claim 1, characterized in that, The conversion leaching includes: The first sulfide ore is subjected to a first leaching to obtain a first leachate and a first molybdenum-containing slag; optionally, the second sulfide ore is subjected to a second leaching to obtain a second leachate and a second molybdenum-containing slag. The oxidized ore is subjected to a third leaching to obtain a third leaching solution and leaching residue, the third leaching solution comprising the first leaching solution, acid, and optionally a second leaching solution; The third leachate is then subjected to separation of molybdenum and uranium to obtain uranium products and a molybdenum organic phase. The first molybdenum-containing slag and / or the second molybdenum-containing slag are purified to obtain ammonium molybdate and a first mother liquor, wherein the first mother liquor is returned to the third leachate for use as raw material in the separation.

3. The method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to claim 2, characterized in that, The first flotation of the radioactive ore to obtain a first sulfide ore and an oxide ore includes: performing a first flotation of the radioactive ore to obtain a first sulfide ore and an intermediate oxide ore, and performing a first blending treatment on the intermediate oxide ore to obtain an oxide ore; The process includes, after the second flotation and before obtaining the second sulfide ore, a second blending treatment of the product obtained from the second flotation.

4. The method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to claim 3, characterized in that, The radioactive mineral processing boundary condition is that the radioactivity activity meets the requirement of 0.1 bq / g-10 bq / g; The first flotation is carried out in a neutral or weakly alkaline environment by adding a first flotation reagent to make the first sulfide ore float to the surface, so as to distinguish the first sulfide ore from the intermediate oxide ore. The conditions for the second flotation include adding a second flotation reagent to the second sulfide ore in a neutral or weakly alkaline environment to cause the second sulfide ore to float. The ore used for the first blending process is uranium ore or uranium-molybdenum ore, with a uranium grade of not less than 0.03% and a molybdenum grade of not less than 0.1%, and the ore must be an oxidizing ore, with molybdenum sulfide accounting for no more than 20%; The second blending ore is molybdenum sulfide ore with a molybdenum grade of not less than 20% and a molybdenum oxide content of not more than 20%. The radioactivity of the second sulfide ore after blending is 0.1 Bq / g to 5 Bq / g.

5. The method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to claim 2, characterized in that, The first leaching and the second leaching each independently satisfy at least one of the following conditions: Oxygen pressure P, air partial pressure P 1、 The relationship between water vapor pressure P2 and pressure vessel working pressure P0 is P + P2 + P1 ≦ P0, P0 = 0.5 MPa ~ 5 MPa; The temperature range is 120℃-200℃; Liquid-to-solid ratio: 1 / 5-1 / 15.

6. The method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to claim 2, characterized in that, The acidity of the first leachate and the second leachate are independently 80 g / L-200 g / L; The acidity of the third leachate is 20 g / L-60 g / L; The molybdenum content in the first molybdenum-containing slag is 20wt%-50wt%; The molybdenum content in the second molybdenum-containing slag is 20wt%-60wt%.

7. The method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to claim 2, characterized in that, The separation includes the following steps: The third leachate, the first mother liquor, and the first conditioning agent are mixed to obtain an extract; After adding a second conditioning agent to the extract, molybdenum extraction and washing are performed to obtain a molybdenum organic phase and a molybdenum raffinate. A third conditioning agent is added to the molybdenum raffinate to form a uranium raffinate stock solution, and the uranium raffinate stock solution is subjected to uranium extraction to obtain uranium extract and uranium raffinate stock solution. The uranium extract is subjected to uranium back-extraction to obtain uranium precipitate and regenerated uranium extractant, wherein the regenerated uranium extractant is returned to the uranium extract; The uranium precipitate is subjected to a first solid-liquid separation to obtain a uranium product and a second mother liquor. The second mother liquor is returned to the uranium extraction stock solution as the raw material for the uranium extraction.

8. The method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to claim 7, characterized in that, The molybdenum organic phase was subjected to molybdenum back-extraction to obtain a molybdenum back-extraction solution and a regenerated molybdenum extractant. The regenerated molybdenum extractant is returned to the molybdenum extraction process.

9. The method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to claim 8, characterized in that, The purification process includes the following steps: The first and second molybdenum-containing slag solutions were dissolved using an alkaline solution to obtain a solution. The solution is subjected to impurity removal and a second solid-liquid separation to obtain ammonium molybdate and a first mother liquor; The molybdenum back-extraction solution is returned to the dissolving solution as the raw material for impurity removal.

10. The method for separating and recovering uranium and molybdenum from complex uranium-molybdenum ores according to claim 7, characterized in that, The acidity of the uranium extraction solution is 10 g / L-30 g / L; The uranium extractant includes an extractant, a diluent, and a phase modifier. The extractant includes N235, the diluent includes sulfonated kerosene, and the phase modifier includes at least one of octanol, mixed alcohols, TBP, etc. The extract has an oxidation-reduction potential of E4 and an acidity of CH4, wherein E4 is 300-600mV and CH4 is 20g / L-40g / L.

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