A process for in-situ leaching of a sandstone type scandium ore

Abstract

The present application belongs to the field of hydrometallurgy, and discloses a sandstone type scandium ore in-situ leaching mining process method, wherein a scandium leaching reagent is injected into a sandstone type scandium ore layer through a liquid injection well, a scandium-containing leaching reagent is pumped out through a liquid pumping well, the scandium-containing solution is subjected to a filtering process, then the scandium-containing solution is subjected to a column adsorption process by taking a functional ion exchange resin as an adsorbent; then the obtained scandium-loaded saturated resin is subjected to elution by a desorption agent, the desorption volume is 1-5 BV, the elution liquid after passing through the column is collected, then oxalic acid is added, and scandium oxide products are obtained through precipitation and calcination. The process method has the advantages of simple operation, green environmental protection, and easy large-scale production, the product purity is as high as 99.9%, and the process method has good industrial application value.

Description

Technical Field

[0001] This invention belongs to the field of hydrometallurgy, and particularly relates to a process for in-situ leaching mining of sandstone scandium ore. Background Technology

[0002] Scandium and its compounds have a wide range of applications due to their unique properties. Metallic scandium has a high melting point, low specific gravity, and is strong, making it suitable for use as aerospace materials, rockets, and aircraft structural materials. In electronics, replacing some of the iron oxide in ferrites with scandium oxide can improve coercivity, thereby enhancing the performance of computer memory components. Scandium can also be used as an activator for oxide cathodes in electron cathode tubes, significantly increasing thermionic emission and extending the cathode life of electron tubes. In the metallurgical industry, scandium is commonly used as an additive in alloys to improve their strength, hardness, and heat resistance. In nuclear technology applications, scandium alloys are ideal high-temperature structural materials due to their good thermal stability. However, scandium is a associated rare element, and there are almost no independent deposits of it in nature. Although the abundance of scandium in the Earth's crust is not very low (approximately 0.0005–0.0006%), its distribution is not concentrated, making the separation and extraction of scandium from ores with complex compositions very difficult. As a result, global scandium production has remained low and its price has been high, limiting its applications.

[0003] The key to scandium extraction lies in solving the cost problem, which in turn depends on improving the scandium extraction methods. Currently, the main processes for scandium extraction and recovery are leaching and extraction, with extraction methods including solvent extraction, precipitation, ion exchange, and liquid membrane extraction. Domestic and international research indicates that the main leaching agents are hydrochloric acid, sulfuric acid, and nitric acid, with hydrochloric acid or sulfuric acid leaching being the most common method. However, hydrochloric acid or sulfuric acid leaching brings significant environmental problems, and conventional extraction methods also have various drawbacks. Therefore, exploring a leaching process for sandstone-type scandium deposits is particularly important. Summary of the Invention

[0004] This invention addresses the significant environmental problems caused by hydrochloric acid or sulfuric acid leaching, as well as the various drawbacks of conventional extraction methods, including the difficulty in preparing high-purity scandium oxide. This invention aims to provide a process for in-situ leaching mining of sandstone-type scandium ore.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A method for in-situ leaching mining of sandstone scandium ore includes the following steps:

[0007] (1) Leaching: Scandium leaching reagent is injected into sandstone-type scandium ore layer through injection well, and then scandium-containing leaching reagent is extracted through pumping well;

[0008] (2) Pretreatment: Filter the scandium-containing leaching reagent from step (1);

[0009] (3) Adsorption: Using scandium-oriented adsorption resin as adsorbent, the scandium-containing leaching reagent filtered in step (2) is adsorbed through a packed column.

[0010] (4) Desorption: The scandium-loaded saturated resin obtained in step (3) is then rinsed with a scandium desorbent, and the eluent after passing through the column is collected.

[0011] (5) Obtaining the product: Oxalic acid is then added, and after precipitation and calcination, scandium oxide is obtained. The purity of the product is as high as 99.9% or more.

[0012] Furthermore, the leaching reagent in step (1) is [R3NH][HSO4], where R3N is any one of TOA, TiOA, and N235, and the concentration of [R3NH][HSO4] is 5-15%, and the amount used is 5-10 times the scandium content of the sandstone scandium ore layer.

[0013] Furthermore, the scandium-directed adsorption resin described in step (3) is a functional ion exchange resin.

[0014] Furthermore, the particle size of the scandium-directed adsorption resin in step (3) is determined according to the mass transfer rate, and is preferably 0.4-0.9 mm.

[0015] Furthermore, the adsorption flow rate in step (3) is determined based on the adsorption rate of scandium, and is preferably 3-5 BV / h.

[0016] Furthermore, the diameter-to-height ratio of the packing column in step (3) is determined based on the mass transfer rate and the adsorption rate of scandium, and is preferably 1:5-10.

[0017] Furthermore, the rinsing flow rate in step (4) is determined based on the mass transfer rate and the scandium desorption rate, and is preferably 2-4 BV / h.

[0018] Furthermore, the operating temperatures for step (3) adsorption and step (4) desorption are determined based on the adsorption and desorption rates of scandium, and the preferred operating temperatures for both adsorption and rinsing are 5-45℃.

[0019] Furthermore, the scandium desorbent in step (4) is hydrochloric acid or sulfuric acid, with a concentration of 3-10% and a dosage of 1-5 BV.

[0020] Furthermore, the specific steps for obtaining the product described in step (5) are as follows:

[0021] Add oxalic acid to the scandium-containing eluent and adjust the pH to about 3.5 to generate scandium oxalate. After calcining at 600-700 degrees Celsius for 2-4 hours, white scandium oxide powder can be obtained.

[0022] The advantages of this invention compared to the prior art are:

[0023] This invention addresses the significant environmental problems caused by hydrochloric acid or sulfuric acid leaching, as well as the various drawbacks of conventional extraction methods, including the difficulty in producing high-purity scandium oxide. This invention provides a sandstone-type scandium ore in-situ leaching mining process. This process is simple to operate, environmentally friendly, and easy for large-scale production, producing a product with a purity of up to 99.9%, making it highly valuable for industrial applications. Detailed Implementation

[0024] The following specific embodiments further illustrate the content of the present invention, but should not be construed as limiting the present invention. Any modifications or substitutions made to the methods, steps, or conditions of the present invention without departing from the spirit and substance of the present invention should be covered within the scope of the claims of the present invention. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can all be obtained commercially.

[0025] Example 1: Preparation of Scandium Directional Adsorption Resin

[0026] At room temperature, 12 parts of 1-methylimidazole and 15 parts of bromobutane were refluxed under sealed conditions for 24 hours. After the reaction was completed, 12 parts of ammonium perrylate solution were added, and the mixture was refluxed for 2 hours. The mixture was washed three times with deionized water. The washed product was then rotary evaporated under vacuum for 3 hours to obtain a rhenium ionic liquid. Then, 30 parts of the rhenium ionic liquid and 30 parts of secondary carbon amine N1923 were added to a three-necked flask as the active component. The temperature was raised to 70°C, and 30 parts of styrene and 0.1 parts of benzoyl peroxide were added as chain initiators. The ultrasonic device was turned on, and the mixture was suspended and copolymerized in the three-necked flask at 70°C. After the particle size of the suspended matter reached 1-5 nm, 9 parts of carboxymethyl chitosan were added for ultrasonic suspension copolymerization. 8 parts of dichloromethane were added to the beads obtained after the reaction for swelling reaction. The temperature was raised to 90°C, and 10 parts of concentrated sulfuric acid were added dropwise. The mixture was then subjected to sulfonation under ultrasonication to obtain a scandium directional adsorption resin.

[0027] Example 2: In-situ leaching mining process for sandstone scandium ore

[0028] (1) Leaching: 5% of scandium leaching reagent [N235H][HSO4] is injected into the sandstone scandium ore layer through the injection well. The amount used is 10 times the scandium content of the sandstone scandium ore layer. Then the scandium-containing leaching reagent is extracted through the pumping well.

[0029] (2) Pretreatment: The scandium-containing solution is filtered;

[0030] (3) Adsorption: Scandium-containing solutions were subjected to column adsorption using a directional adsorption resin with a particle size of 0.4 mm. The adsorption flow rate was 3 BV / h and the diameter-to-height ratio of the packing column was 1:5.

[0031] (4) Desorption: The obtained scandium-loaded saturated resin is then eluted with a desorbent, which is 3% sulfuric acid, with a desorption volume of 5 BV and an operating temperature of 20°C. The eluent after passing through the column is collected.

[0032] (5) Obtaining the product: Add oxalic acid to the scandium-containing leaching solution and adjust the pH to about 3.5 to generate scandium oxalate. After calcining at 700 degrees for 2 hours, white scandium oxide powder can be obtained with a purity of over 99.9%.

[0033] Example 3: In-situ leaching mining process for sandstone scandium ore

[0034] (1) Leaching: 15% scandium leaching reagent [TOAH][HSO4] is injected into the sandstone scandium ore layer through the injection well. The amount used is 5 times the scandium content of the sandstone scandium ore layer. Then the scandium-containing leaching reagent is extracted through the pumping well.

[0035] (2) Pretreatment: The scandium-containing solution is filtered;

[0036] (3) Adsorption: Scandium-containing solutions were subjected to column adsorption using a directional adsorption resin with a particle size of 0.5 mm. The adsorption flow rate was 4 BV / h, the diameter-to-height ratio of the packing column was 1:8, and the operating temperature was 20℃.

[0037] (4) Desorption: The obtained scandium-loaded saturated resin is then eluted with a desorbent, which is 3% hydrochloric acid. The desorption volume is 4 BV, the operating temperature is 20℃, and the eluent after passing through the column is collected.

[0038] (5) Obtaining the product: Add oxalic acid to the scandium-containing eluent and adjust the pH to about 3.5 to generate scandium oxalate. After calcining at 600 degrees Celsius for 4 hours, white scandium oxide powder can be obtained. The purity of the product is as high as 99.9% or more.

[0039] Example 4: In-situ leaching mining process for sandstone scandium ore

[0040] (1) Leaching: 10% scandium leaching reagent [TiOAH][HSO4] is injected into the sandstone scandium ore layer through the injection well. The amount used is 8 times the scandium content of the sandstone scandium ore layer. Then the scandium-containing leaching reagent is extracted through the pumping well.

[0041] (2) Pretreatment: The scandium-containing solution is filtered;

[0042] (3) Adsorption: Scandium-containing solutions were subjected to column adsorption using a directional adsorption resin with a particle size of 0.9 mm. The adsorption flow rate was 5 BV / h, the diameter-to-height ratio of the packing column was 1:10, and the operating temperature was 30℃.

[0043] (4) Desorption: The obtained scandium-loaded saturated resin is then eluted with a desorbent, which is 5% hydrochloric acid. The desorption volume is 4 BV, the operating temperature is 30℃, and the eluent after passing through the column is collected.

[0044] (5) Obtaining the product: Add oxalic acid to the scandium-containing leaching solution and adjust the pH to about 3.5 to generate scandium oxalate. After calcining at 650 degrees for 3 hours, white scandium oxide powder can be obtained with a purity of over 99.9%.

[0045] The embodiments described above are merely preferred embodiments of the present invention, and not all feasible embodiments of the present invention. Any obvious modifications made by those skilled in the art without departing from the principles and spirit of the present invention should be considered to be included within the scope of protection of the claims of the present invention.

Claims

1. A method for in-situ leaching mining of sandstone scandium ore, characterized in that, Includes the following steps: (1) Leaching: The scandium leaching reagent is injected into the sandstone scandium ore layer through the injection well, and then the scandium-containing leaching reagent is extracted through the pumping well; the leaching reagent is [R3NH][HSO4], R3N is any one of TOA, TiOA, N235, the concentration of [R3NH][HSO4] is 5-15%, and the amount used is 5-10 times the scandium content of the sandstone scandium ore layer; (2) Pretreatment: The scandium-containing leaching reagent from step (1) is filtered; (3) Adsorption: Using scandium-oriented adsorption resin as adsorbent, the scandium-containing leaching reagent filtered in step (2) is adsorbed through a packed column; (4) Desorption: The scandium-loaded saturated resin obtained in step (3) is then rinsed with a scandium desorbent, and the eluent after passing through the column is collected. (5) Obtaining the product: Oxalic acid is then added, and after precipitation and calcination, scandium oxide is obtained.

2. The in-situ leaching mining process for sandstone-type scandium ore as described in claim 1, characterized in that, The scandium-directed adsorption resin mentioned in step (3) is a functional ion exchange resin.

3. The in-situ leaching mining process for sandstone-type scandium ore as described in claim 1, characterized in that, The particle size of the scandium directional adsorption resin in step (3) is determined according to the mass transfer rate and is 0.4-0.9 mm.

4. The in-situ leaching mining process for sandstone-type scandium ore as described in claim 1, characterized in that, The flow rate of the leaching reagent during the adsorption process described in step (3) is determined based on the adsorption rate of scandium and is 3-5 BV / h.

5. The in-situ leaching mining process for sandstone-type scandium ore as described in claim 1, characterized in that, The diameter-to-height ratio of the packing column in step (3) is determined based on the mass transfer rate and the adsorption rate of scandium, and is 1:5-10.

6. The in-situ leaching mining process for sandstone-type scandium ore as described in claim 1, characterized in that, The rinsing flow rate in step (4) is determined based on the mass transfer rate and the scandium desorption rate, and is 2-4 BV / h.

7. The in-situ leaching mining process for sandstone-type scandium ore as described in claim 1, characterized in that, The operating temperatures for step (3) adsorption and step (4) desorption are determined based on the adsorption and desorption rates of scandium. The operating temperatures for both adsorption and rinsing are 5-45 ℃.

8. The in-situ leaching mining process for sandstone-type scandium ore as described in claim 1, characterized in that, The scandium desorbent in step (4) is hydrochloric acid or sulfuric acid, with a concentration of 3-10% and a dosage of 1-5 BV.

9. The in-situ leaching mining process for sandstone-type scandium ore as described in claim 1, characterized in that, The specific steps for obtaining the product in step (5) are as follows: add oxalic acid to the scandium-containing leaching solution, adjust the pH to 3.5 to generate scandium oxalate, and calcine it at 600-700 degrees for 2-4 hours to obtain white scandium oxide powder.