Method for co-processing rubidium ore by sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals

Abstract

The invention provides a method for treating rubidium ore through cooperation of sulfuric acid and hydrochloric acid and comprehensively utilizing valuable metals, and belongs to the technical field of rare metal extraction. The ground rubidium ore is subjected to ore phase activation with hydrochloric acid, impurity calcium in the rubidium ore is synchronously removed, and activated slag and activated liquid are obtained; decalcifying the activating solution by using sulfuric acid, and recycling the obtained regenerated hydrochloric acid; curing and roasting the activated slag by using concentrated sulfuric acid to obtain cured slag; performing water leaching on the cured slag to obtain silicon slag and water leaching liquid; separating rubidium from the water extract through controllable cooling crystallization to obtain a rubidium-containing enriched product and a crystallization residual liquid, and sequentially dissolving, extracting and reversely extracting the rubidium-containing enriched product to obtain rubidium salt; performing freezing crystallization on residual crystallization liquid to obtain potassium alum, and returning crystallization mother liquor to serve as leaching water. According to the method, rubidium and potassium products with high economic value are produced, a large number of components of aluminum and silicon are productized, comprehensive utilization of resources is achieved, and the method has the advantages of being short in technological process and easy and convenient to operate.

Description

Technical Field

[0001] The present invention belongs to the technical field of rare metal extraction, and particularly relates to a method for synergistically treating rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals. Background Art

[0002] Rubidium is a soft, silver-white low-melting-point active light metal with excellent optoelectronic properties, electrical conductivity, thermal conductivity, and strong chemical activity. Rubidium compounds and alloys are important materials for manufacturing photocells, photomultiplier tubes, and atomic clocks, and are also essential materials for infrared technology.

[0003] Although rubidium ore resources are relatively abundant and rubidium has a wide range of uses, the production and consumption of rubidium are both low. On the one hand, currently, the processes for extracting rubidium from minerals include roasting method, acid method, autoclaving method, etc., but the processes are complicated and the technical difficulty is high, resulting in low production and high price of rubidium, and the high price leads to low consumption demand. On the other hand, most of the rubidium extraction processes do not consider the comprehensive recovery of its associated components (such as potassium, aluminum, silicon, etc.), resulting in low resource comprehensive utilization efficiency and few profit points. In order to effectively develop and utilize rubidium ore, scientific research workers have carried out a large number of related studies and obtained a lot of valuable experience.

[0004] Chinese Patent CN202311098525.9 discloses a method for extracting rubidium from low-sodium carnallite and a method for comprehensive utilization of low-sodium carnallite. By treating low-sodium carnallite through a cold decomposition method to obtain solid KCl and high-magnesium mother liquor, and then using an organic solvent for washing, impurity removal, and extraction, an RbCl solution can be obtained. Chinese Patent CN202311071617.8 discloses a method for extracting and separating rubidium and cesium from roasted rubidium mica ore. By roasting with a specially added auxiliary agent and a composite chlorinating agent, leaching the roasted ore with dilute sulfuric acid, and using a composite extraction system to simultaneously extract rubidium and cesium and then back-extracting to separate rubidium and cesium.

[0005] Through the above methods, rubidium can be extracted to a certain extent, but the recovery of other elements has not been studied. Therefore, comprehensively treating rubidium ore is of great significance for improving the comprehensive utilization efficiency of resources. Summary of the Invention

[0006] The method for comprehensively extracting valuable metals from rubidium ore provided by the present invention can realize the comprehensive extraction of valuable metals in the ore on the basis of lower production costs under the synergistic treatment of sulfuric acid / hydrochloric acid, can make full use of the ore raw materials, and increase economic benefits.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for synergistically treating rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals, comprising the following steps:

[0009] Step S1: Grind the rubidium ore;

[0010] Step S2: Use hydrochloric acid to activate the mineral phase of the ground rubidium ore and simultaneously remove the impurity calcium therein to obtain activated slag and activated liquid;

[0011] Step S3: Use sulfuric acid to remove calcium from the activated liquid, and recycle the regenerated hydrochloric acid obtained to Step S2 for utilization;

[0012] Step S4: Use concentrated sulfuric acid to cure and roast the activated slag to obtain cured slag;

[0013] Step S5: Leach the cured slag with water to obtain silica slag and leaching solution. The silica slag is separated by gravity separation to obtain tantalum and niobium concentrates and silica-rich slag. The silica-rich slag can be reused to prepare products such as glass, silicon fertilizer, and white carbon black;

[0014] Step S6: Separate rubidium from the leaching solution in Step S5 by controlled cooling crystallization to obtain rubidium-rich concentrate and crystallization residue liquid. The rubidium-rich concentrate is successively dissolved, extracted, and back-extracted to obtain rubidium salt;

[0015] Step S7: Potassium alum is obtained from the crystallization residue liquid in Step S6 by freeze crystallization, and the crystallization mother liquor can be returned to Step S5 as leaching water.

[0016] Further, in Step S1, the rubidium ore is ground to a particle size of ≤ 74 μm.

[0017] Further, in Step S2, the concentration of hydrochloric acid is 0.1 - 3 mol / L, the activation temperature is 20 - 100 °C, the activation time is 10 - 120 min, and the liquid-solid ratio of the activation liquid is 1:1 - 10:1 mL / g. The reaction is: 2HCl + CaCO3 = Ca 2+ + 2Cl - + H2O + CO2. Since the sulfate radical in sulfuric acid will combine with calcium ions to form a precipitate, and the cost of nitric acid and the subsequent recovery cost are higher, hydrochloric acid activation is used in the present invention. The main components of the activated slag are mica and silicon dioxide, and the main ions in the activated liquid are Ca 2+ .

[0018] Further, in Step S3, the temperature of the calcium removal reaction is room temperature, the stirring speed is 100 - 400 rpm, the reaction time is 30 - 120 min, and the amount of sulfuric acid used is 1 - 3 times the theoretical amount. The reaction formula is: H2SO4 + Ca 2+ = CaSO4 + 2H + . Since the liquid phase contains H + and Cl - , it can be recycled to Step S2 as hydrochloric acid for utilization. The mass concentration of the sulfuric acid ≥ 70%.

[0019] Further, in step S4, the aging roasting temperature is 150 - 310 °C, the roasting time is 1 - 7 h, and the dosage of H2SO4 is 0.5 - 2 times the chemical reaction equivalent. The reaction formula is: 10H + +(K, Rb)Al3Si3O 10 (OH)2=(K + , Rb + )+3Al 3+ +3SiO2+6H2O. The concentrated sulfuric acid is sulfuric acid with a concentration ≥ 70wt%. During actual operation, concentrated sulfuric acid is added to the activated slag, and after stirring evenly, it is directly heated to the set temperature. The role of aging roasting is to convert some metal elements in the activated slag, such as potassium, rubidium, and aluminum, into leachable ions. If the aging temperature is too low, the ion leaching rate will be low; if the temperature is too high, sulfuric acid will decompose.

[0020] Further, in step S5, the water leaching temperature is 20 - 100 °C, the water leaching time is 10 - 180 min, and the liquid-solid ratio of the leaching solution is 1:1 - 10:1 mL / g. The water leaching solution mainly contains potassium sulfate, rubidium sulfate, aluminum sulfate, etc.; the main component of the silicon slag is silicon dioxide.

[0021] Further, in step S6, the crystallization temperature is 20 - 70 °C. The main component of the rubidium-rich product is rubidium alum, and the rubidium concentration in the mother liquor is 0.01 - 0.1 g / L. The reaction formula is: Rb + +Al 3+ +2SO4 2- +12H2O=RbAl(SO4)2·12H2O.

[0022] Further, in step S7, the crystallization temperature is -20 - 10 °C. The reaction formula is: K + +Al 3+ +2SO4 2- +12H2O=KAl(SO4)2·12H2O.

[0023] The beneficial effects brought by the technical solution provided by the present invention at least include:

[0024] This method makes full use of the valuable components in the rubidium ore. When using this new process route for extracting rubidium from the ore, under the synergistic action of sulfuric acid / hydrochloric acid, first activate the rubidium ore phase and simultaneously remove the impurity calcium therein. The silicon content in the leaching residue after aging is high. After separating niobium and tantalum by gravity separation, products such as glass, silicon fertilizer, and white carbon black can be refined from the leaching residue. The sulfuric acid aging leaching solution separates rubidium by controlled cooling crystallization to obtain a rubidium-enriched product. This process can reduce the difficulty of subsequent extraction and separation of rubidium and improve the extraction efficiency, while reducing the loss of the extractant. The crystallization mother liquor obtains potassium alum through low-temperature crystallization, and the crystallization mother liquor can be returned to the leaching process, which has good economic and environmental benefits. The process flow is simple, the equipment investment is low, and the operation is convenient. Moreover, the wastewater generated in the process can be returned to the process for reuse, and no waste residue is generated. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0026] Figure 1 It is a process flow chart for comprehensively extracting valuable metals from rubidium ore of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] To make the technical problems, technical solutions, and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the drawings and specific embodiments.

[0028] Example 1

[0029] (1) Mix the rubidium ore (Rb 0.13%, Ca 1.92%, Si 31.81%, Al 8.0%, K 3.7%, all the above are mass percentages, and the same source of rubidium ore is used in other examples) with 1 mol / L hydrochloric acid solution, the liquid-solid ratio is 5:1 mL / g, activate at 80 °C for 1 h, and the calcium removal rate is 97.2%.

[0030] (2) Add sulfuric acid to the activated solution filtered in step (1), the reaction temperature is room temperature, the amount of sulfuric acid used is 1 times the theoretical amount, the stirring speed is 200 rpm, the reaction time is 60 min, the hydrochloric acid recovery rate is 86.45%, and the calcium recovery rate is 95.2%.

[0031] (3) Add concentrated sulfuric acid to the activated residue filtered in step (1), the amount of sulfuric acid is 1.6 times the theoretical acid amount, and react at 250 °C for 6 h. The mass concentration of sulfuric acid used in steps (2) and (3) ≥70%.

[0032] (4) Leach the matured slag in step (3) with water at a liquid-solid ratio of 5:1 mL / g and leach for 1.5 h at a temperature of 80 °C. The rubidium extraction rate is 84.2% and the purity of silicon dioxide is 96.1%.

[0033] (5) Crystallize the leachate in step (4) at low temperature. The crystallization temperature is 50 °C, the rubidium concentration in the mother liquor is 0.05 g / L, the crystallization rate of rubidium alum is 86%. After dissolution / extraction / back-extraction, rubidium salt with a purity of 98.7% is obtained.

[0034] (6) Freeze-crystallize the crystallization residue liquid in step (5) at a crystallization temperature of 0 °C. The crystallization rate of potassium alum is 98%. After roasting / dissolving the alum, the aluminum recovery rate is 88.2% and the potassium recovery rate is 86.3%.

[0035] Example 2

[0036] (1) Mix the rubidium ore with 1 mol / L hydrochloric acid solution at a liquid-solid ratio of 5:1 mL / g and activate for 1.5 h at a temperature of 80 °C. The calcium removal rate is 98.4%.

[0037] (2) Add sulfuric acid to the activated liquid filtered in step (1). The amount of sulfuric acid used is 1.5 times the theoretical amount. The reaction temperature is room temperature, the stirring speed is 300 rpm, and the reaction time is 90 min. The hydrochloric acid recovery rate is 94.89% and the calcium recovery rate is 96.2%.

[0038] (3) Add concentrated sulfuric acid to the activated slag filtered in step (1). The amount of sulfuric acid is the theoretical acid amount and react at 290 °C for 5 h. The mass concentration of sulfuric acid used in steps (2) and (3) ≥ 70%.

[0039] (4) Leach the matured slag in step (3) with water at a liquid-solid ratio of 5:1 mL / g and leach for 1.5 h at a temperature of 80 °C. The rubidium extraction rate is 87.6% and the purity of silicon dioxide is 97.6%.

[0040] (5) Crystallize the leachate in step (4) at low temperature. The crystallization temperature is 45 °C, the rubidium concentration in the mother liquor is 0.08 g / L, the crystallization rate of rubidium alum is 82%. After dissolution / extraction / back-extraction, rubidium salt with a purity of 98.3% is obtained.

[0041] (6) Freeze-crystallize the crystallization residue liquid in step (5) at a temperature of -10 °C. The crystallization rate of potassium alum is 99.1%. After roasting / dissolving the alum, the aluminum recovery rate is 85.2% and the potassium recovery rate is 87.5%.

[0042] Example 3

[0043] (1) Mix the rubidium ore with 1 mol / L hydrochloric acid solution at a liquid-solid ratio of 3:1 mL / g, and activate it at 80 °C for 2.5 h. The calcium removal rate is 99.5%.

[0044] (2) Add sulfuric acid to the activated solution filtered in step (1). The amount of sulfuric acid used is 2.5 times the theoretical amount. The reaction temperature is room temperature, the stirring speed is 400 rpm, and the reaction time is 120 min. The hydrochloric acid recovery rate is 97.52%, and the calcium recovery rate is 96.8%.

[0045] (3) Add concentrated sulfuric acid to the activated slag filtered in step (1). The amount of sulfuric acid is the theoretical acid amount, and react at 270 °C for 6 h. The mass concentration of sulfuric acid used in steps (2) and (3) is ≥70%.

[0046] (4) Leach the ripened slag in step (3) with water at a liquid-solid ratio of 5:1 mL / g, and leach at 90 °C for 1.5 h. The rubidium extraction rate is 86.2%, and the purity of silicon dioxide is 96.3%.

[0047] (5) Crystallize the leachate in step (4) at low temperature. The crystallization temperature is 50 °C, the rubidium concentration in the mother liquor is 0.01 g / L, the crystallization rate of rubidium alum is 89.3%, and then through dissolution / extraction / extraction, rubidium salt with a purity of 89.12% is obtained.

[0048] (6) Freeze-crystallize the crystallization residue liquid in step (5) at -5 °C. The crystallization rate of potassium alum is 96.8%. After roasting / dissolving the alum, the aluminum recovery rate is 82.1%, and the potassium recovery rate is 89.5%.

[0049] Example 4

[0050] (1) Mix the rubidium ore with 2 mol / L hydrochloric acid solution at a liquid-solid ratio of 3:1 mL / g, and activate it at 100 °C for 1 h. The calcium removal rate is 95.2%.

[0051] (2) Add sulfuric acid to the activated solution filtered in step (1). The amount of sulfuric acid used is 2 times the theoretical amount. The reaction temperature is room temperature, the stirring speed is 300 rpm, and the reaction time is 120 min. The hydrochloric acid recovery rate is 95.56%, and the calcium recovery rate is 95.9%.

[0052] (3) Add concentrated sulfuric acid to the activated slag filtered in step (1). The amount of sulfuric acid is the theoretical acid amount, and react at 250 °C for 7 h. The mass concentration of sulfuric acid used in steps (2) and (3) is ≥70%.

[0053] (4) Leach the ripened slag in step (3) with water at a liquid-solid ratio of 3:1 mL / g and leach for 2 h at a temperature of 80 °C. The rubidium extraction rate is 79.2%, and the purity of silicon dioxide is 94.3%.

[0054] (5) Crystallize the leachate in step (4) at low temperature. The crystallization temperature is 35 °C, the rubidium concentration in the mother liquor is 0.03 g / L, the crystallization rate of rubidium alum is 82.8%. Then, through dissolution / extraction / back-extraction, rubidium salt with a purity of 97.2% is obtained.

[0055] (6) Freeze-crystallize the crystallization mother liquor in step (5) at a crystallization temperature of 0 °C. The crystallization rate of potassium alum is 99.4%. After roasting / dissolving the alum, the aluminum recovery rate is 86.2%, and the potassium recovery rate is 87.8%.

[0056] Comparative Example 1

[0057] (1) Mix the rubidium ore with 1 mol / L nitric acid solution at a liquid-solid ratio of 5:1 mL / g and activate for 1 h at a temperature of 80 °C. The calcium removal rate is 84.21%.

[0058] (2) Add sulfuric acid to the activated liquid filtered in step (1). The amount of sulfuric acid used is 2 times the theoretical amount. The reaction temperature is room temperature, the stirring speed is 300 rpm, and the reaction time is 120 min. The hydrochloric acid recovery rate is 96.53%, and the calcium recovery rate is 97.25%.

[0059] (3) Add concentrated sulfuric acid to the activated slag filtered in step (1). The amount of sulfuric acid is the theoretical acid amount, and react at 250 °C for 7 h. The mass concentration of sulfuric acid used in steps (2) and (3) ≥70%.

[0060] (4) Leach the ripened slag in step (3) with water at a liquid-solid ratio of 3:1 mL / g and leach for 2 h at a temperature of 80 °C. The rubidium extraction rate is 80.51%, and the purity of silicon dioxide is 93.46%.

[0061] (5) Crystallize the leachate in step (4) at low temperature. The crystallization temperature is 35 °C, the rubidium concentration in the mother liquor is 0.03 g / L, the crystallization rate of rubidium alum is 80.52%. Then, through dissolution / extraction / back-extraction, rubidium salt with a purity of 98.63% is obtained.

[0062] (6) Freeze-crystallize the crystallization mother liquor in step (5) at a crystallization temperature of 0 °C. The crystallization rate of potassium alum is 99.3%. After roasting / dissolving the alum, the aluminum recovery rate is 84.29%, and the potassium recovery rate is 89.76%. Comparative Example 1 uses nitric acid activation, and other steps are basically the same as in Example 4. The purity of rubidium salt and the recovery rates of aluminum and potassium are not very different from those in Example 4. However, compared with using hydrochloric acid, when using nitric acid, the cost of purifying 1 kg of rubidium salt increases by 70,000 yuan. Therefore, hydrochloric acid activation is used in the present invention.

[0063] Comparative Example 2

[0064] (1) Mix the rubidium ore with 1.5 mol / L hydrochloric acid solution, with a liquid-solid ratio of 4:1 mL / g, activate it at a temperature of 100 °C for 1 h, and the calcium removal rate is 94.89%.

[0065] (2) Add sulfuric acid to the activated solution filtered in step (1). The amount of sulfuric acid used is 2 times the theoretical amount. The reaction temperature is room temperature, the stirring speed is 300 rpm, the reaction time is 120 min, the hydrochloric acid recovery rate is 97.21%, and the calcium recovery rate is 93.54%.

[0066] (3) Add concentrated sulfuric acid to the activated slag filtered in step (1). The amount of sulfuric acid is the theoretical acid amount, and react at 350 °C for 7 h. The mass concentration of sulfuric acid used in steps (2) and (3) ≥ 70%.

[0067] (4) Leach the ripened slag in step (3) with water, with a liquid-solid ratio of 5:1 mL / g, leach at a temperature of 80 °C for 2 h, the rubidium extraction rate is 40.52%, and the purity of silicon dioxide is 83.48%.

[0068] (5) Crystallize the leachate in step (4) at low temperature. The crystallization temperature is 35 °C, the rubidium concentration in the mother liquor is 0.01 g / L, the crystallization rate of rubidium alum is 81.54%, and then through dissolution / extraction / back-extraction, rubidium salt with a purity of 95.62% is obtained.

[0069] (6) Freeze-crystallize the crystallization residual liquid in step (5). The crystallization temperature is 0 °C, and the crystallization rate of potassium alum is 99.23%. After the alum is calcined / dissolved, the aluminum recovery rate is 62.54%, and the potassium recovery rate is 49.62%. In Comparative Example 2, the temperature during the activation roasting with concentrated sulfuric acid is too high, and the other steps are basically the same as in Example 4. Due to the too high temperature, part of the sulfuric acid decomposes. The purity of the rubidium salt is not much different from that in Example 4, but the aluminum and potassium recovery rates are significantly reduced.

[0070] As described above, it is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claimed rights.

Claims

1. A method for co - treating rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals, characterized in that, It includes the following steps: Step S1: Grind the rubidium ore; Step S2: Use hydrochloric acid to activate the mineral phase of the ground rubidium ore and simultaneously remove the impurity calcium therein to obtain activated slag and activated liquid; Step S3: Use sulfuric acid to remove calcium from the activated liquid, and recycle the obtained regenerated hydrochloric acid to Step S2 for utilization; Step S4: Use concentrated sulfuric acid to cure and roast the activated slag to obtain cured slag; Step S5: Leach the cured slag with water to obtain silicon slag and leaching solution; Step S6: Crystallize and separate rubidium from the leaching solution in Step S5 by controlled cooling to obtain rubidium-rich concentrate and crystallization mother liquor. The rubidium-rich concentrate is successively dissolved, extracted and back-extracted to obtain rubidium salt; Step S7: Potassium alum is obtained by freezing crystallization of the crystallization mother liquor in Step S6, and the crystallization mother liquor can be returned to Step S5 as leaching water.

2. The method for co-processing rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals according to claim 1, characterized in that, In Step S1, the rubidium ore is ground to a particle size of ≤74 μm.

3. The method for co-processing rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals according to claim 1, wherein In Step S2, the concentration of hydrochloric acid is 0.1 - 3 mol / L, the activation temperature is 20 - 100 °C, the activation time is 10 - 120 min, and the liquid-solid ratio of the activation liquid is 1:1 - 10:1 mL / g.

4. The method for co-processing rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals according to claim 1, characterized in that, In Step S3, the calcium removal reaction temperature is room temperature, the stirring speed is 100 - 400 rpm, the reaction time is 30 - 120 min, and the amount of sulfuric acid used is 1 - 3 times the theoretical amount.

5. The method for co-processing rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals according to claim 1, characterized in that, In Step S4, the curing and roasting temperature is 150 - 310 °C, the roasting time is 1 - 7 h, the amount of H2SO4 used is 0.5 - 2 times the chemical reaction equivalent, and the concentrated sulfuric acid is sulfuric acid with a concentration of ≥70wt%.

6. The method for co-processing rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals according to claim 1, wherein In Step S5, the water leaching temperature is 20 - 100 °C, the water leaching time is 10 - 180 min, and the leaching liquid-solid ratio is 1:1 - 10:1 mL / g.

7. The method for co - treating rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals according to claim 1, wherein In Step S6, the crystallization temperature is 20 - 70 °C, and the rubidium concentration in the mother liquor is 0.01 - 0.1 g / L.

8. The method for co-processing rubidium ore with sulfuric acid / hydrochloric acid and comprehensively utilizing valuable metals according to claim 1, characterized in that, In Step S7, the crystallization temperature is -20 - 10 °C.

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