A method for preventing organic phase dissolution loss in rare earth extraction process

Abstract

The present application provides a method for preventing the dissolution loss of an organic phase in a rare earth extraction process, comprising the following steps: (1) dissolving an extractant in a predetermined diluent to obtain an organic extraction solution; (2) mixing the organic extraction solution in step (1) with an inorganic alkali solution to obtain a saponified organic phase; (3) stirring and mixing the diluted organic solution of anhydrous sorbitan fatty acid ester with the organic extraction solution prepared in step (1) or the saponified organic phase prepared in step (2) or the regenerated organic phase obtained in step 5) to obtain a blended organic phase; (4) mixing and extracting the blended organic phase prepared in step (3) with a rare earth ion solution, allowing the mixture to stand for phase separation, and obtaining a raffinate and a rare earth ion-loaded organic phase; (5) mixing the rare earth ion-loaded organic phase obtained in step (4) with a hydrochloric acid solution for back extraction to obtain a rare earth-rich aqueous solution and a regenerated organic phase. The present application can control the oil content in the raffinate to below 10 mg / L, and the rare earth extraction rate can be as high as 99.8%.

Description

Technical Field

[0001] The invention belongs to the technical field of solvent extraction and separation, in particular to a method for preventing organic phase dissolution loss in a rare earth extraction process. Background Art

[0002] Solvent extraction is an important chemical separation technology with advantages such as high selectivity, good separation effect, easy operation and strong applicability. It is widely used in the fields of petroleum, chemical industry, pharmaceuticals, metallurgy, environmental protection, bioengineering and new material preparation. Traditional solvent extraction methods have organic phase dissolution losses during rare earth extraction. Especially when emulsification or the third phase occurs, the organic phase solvent loss is extremely serious. The price of organic phase is generally expensive. The dissolution of organic phase during extraction not only wastes resources, but also produces a large amount of oily wastewater. If it is not treated, it will cause serious ecological pollution. Therefore, how to completely prevent the dissolution loss of organic phase during rare earth extraction from the source has become a bottleneck problem restricting the development of the industry.

[0003] In the prior art, CN200910094470 discloses a method for eliminating the emulsification of amine and phosphorus organic reagent extraction. This method involves adding a metal cleaning agent with the trade name CSP-925, CSQ-926, or GEA-746 to the aqueous phase in an amount of 0.1 to 1 g / L. This method does not produce emulsification, allowing smooth production. CN89104730 discloses a method for eliminating the emulsification of yttrium concentrate acid solution extraction. This method involves adding sodium sulfide to the aqueous solution, using sodium sulfide as a precipitant to remove aluminum, iron, and heavy metal impurities from the aqueous solution, and then adding barium chloride for precipitation. This process method can thoroughly remove aluminum, iron, and heavy metal impurities and is suitable for the pretreatment of various yttrium concentrates. The purified feed liquid can meet the requirements of the extraction feed liquid. No emulsification occurs during the extraction and separation of yttrium, saving raw material consumption and improving the recovery rate of rare earths. CN201510518925 discloses a coal chemical wastewater extraction and emulsification control agent, its preparation method, and use. The method first adds a cationic polymer and a nonionic polymer to water in proportion, then adds C3-C7 ketones and an inorganic salt and stirs to obtain an additive. The additive provided by the present invention is designed based on the characteristics of the emulsified intermediate layer of coking wastewater, and can assist the demulsifier in achieving rapid demulsification of the emulsified intermediate layer, thereby recovering the lost extractant. However, the above-mentioned disclosed technologies all add reagents to the aqueous phase. Although this can effectively prevent emulsification, it cannot control the dissolution of the organic phase and also causes secondary water pollution.

[0004] In view of this, this application is hereby filed. Summary of the Invention

[0005] In order to solve one of the above technical defects, a method for preventing the dissolution loss of the organic phase in the rare earth extraction process is provided in an embodiment of the present application.

[0006] According to a first aspect of an embodiment of the present application, a method for preventing organic phase dissolution loss during a rare earth extraction process is provided, comprising:

[0007] (1) dissolving the extractant in a predetermined diluent to obtain an organic extraction solution;

[0008] (2) mixing the organic extraction solution in step (1) with an inorganic alkali solution to obtain a saponified organic phase;

[0009] (3) stirring and mixing the diluted organic solution of sorbitan fatty acid ester with the organic extraction solution prepared in step (1), the saponified organic phase prepared in step (2), or the regenerated organic phase obtained in step 5) to obtain a blended organic phase;

[0010] (4) extracting the blended organic phase prepared in step (3) with the rare earth ion solution, allowing the mixture to stand for phase separation to obtain a raffinate and an organic phase loaded with rare earth ions;

[0011] (5) The rare earth ion-loaded organic phase obtained in step (4) is mixed with a hydrochloric acid solution and stripped to obtain a rare earth-rich aqueous solution and a regenerated organic phase.

[0012] Preferably, step (2) comprises dissolving an inorganic alkali solution in water to obtain an inorganic alkali aqueous solution; then adding the solution dropwise to the organic extraction solution prepared in step (1) for saponification; and the dropping rate of the inorganic alkali aqueous solution is 0.05 to 20.0 mL / min.

[0013] Preferably, the concentration of the inorganic alkali aqueous solution is 1.0 to 12.0 mol / L;

[0014] The concentration of the hydrochloric acid solution in step 5) is 1.0 to 12.0 mol / L.

[0015] Preferably, the extractant is an acidic extractant, an amine extractant or a synergistic extraction system; the acidic extractant is one or a combination of two or more of P507, P204, C272, and cyclohexane acid;

[0016] The amine extractant is one or a combination of N235, N236, and N1923;

[0017] The synergistic extraction system is one or a combination of P507-TBP, P204-TBP, C272-TBP, P507-N235, P507-P204, P507-C272, P507-N263, P204-N263, P204-N235, C272-N263, C272-N235, P507-N1923, P204-N1923, and C272-N1923.

[0018] Preferably, the inorganic alkali solution is sodium hydroxide, potassium hydroxide or ammonia water.

[0019] Preferably, before step (3), the method further comprises:

[0020] The sorbitan fatty acid ester is diluted in an organic solvent to obtain a diluted sorbitan fatty acid ester organic solution.

[0021] Preferably, the amount of the sorbitan fatty acid ester added is 0% to 15% of the mass of the extractant in the organic solution;

[0022] The concentration of sorbitan fatty acid ester in the sorbitan fatty acid ester organic solution is 0 to 250 g / L;

[0023] The stirring speed during the stirring and mixing in the step (3) is 0 to 200 rpm.

[0024] Preferably, during extraction, the stirring speed is 50 to 300 rpm, and the volume ratio of the organic phase to the rare earth ion-containing solution is 50:1 to 1:0.5.

[0025] Preferably, in step (3), the pH value of the rare earth ion solution is 2-4; the total concentration of the rare earth ion solution is 0-2 g / L; and the temperature of the rare earth ion solution is 5-40°C.

[0026] Preferably, the preset diluent is an aliphatic hydrocarbon or aromatic hydrocarbon diluent having a boiling point above 200° C. under normal pressure.

[0027] Beneficial effects of this application:

[0028] 1. The present invention provides a method for preventing the dissolution loss of the organic phase during the rare earth extraction process. This method can effectively prevent the dissolution loss of the organic phase during the extraction and separation of rare earths without affecting the extraction efficiency, avoid the loss of expensive extractants, greatly improve resource utilization, and save costs.

[0029] 2. The present invention provides a method for preventing the dissolution loss of the organic phase during the rare earth extraction process. This method can effectively prevent the dissolution loss of the organic phase during the extraction and separation of rare earths, reduce the generation of oily wastewater, not only save costs but also protect the ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0031] Figure 1 Different organic phases at 1800-1100cm -1Infrared spectra over a range of wavelengths. DETAILED DESCRIPTION

[0032] In order to make the technical solutions and advantages of the embodiments of the present application more clearly understood, the exemplary embodiments of the present application are further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, and are not an exhaustive list of all the embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other unless they conflict.

[0033] Example 1:

[0034] (1) dissolving the acidic extractant P507 in kerosene to obtain a 1.5 mol / L P507 kerosene solution;

[0035] (2) adding a 10 mol / L sodium hydroxide solution to a 1.5 mol / L LP507 kerosene solution at a rate of 10.0 mL / min to saponify the obtained saponified organic phase, the degree of saponification of which was 12%;

[0036] (3) Add a kerosene solution of Span 80 having a concentration of 100 g / L to the obtained saponified organic phase, preferably at a stirring speed of 100 rpm, to obtain a blended organic phase in which the content of Span 80 is 10%.

[0037] (4) The resulting blended organic phase was mixed with a rare earth ion-containing solution for extraction, and the mixture was allowed to stand for phase separation to obtain a raffinate and a rare earth ion-loaded organic phase. The rare earth ion concentration in the aqueous solution was 200 mg / L, the pH value of the aqueous solution was 3, the temperature of the aqueous solution was 20°C, the stirring speed was 200 rpm, and the volume ratio of the blended organic phase to the rare earth-containing aqueous solution used for extraction was 1:2. The oil content in the raffinate was determined to be 5 mg / L, and the rare earth extraction yield was 99.8%.

[0038] (5) The rare earth ion-loaded organic phase is mixed with a 6 mol / L hydrochloric acid solution for stripping to obtain a rare earth-rich aqueous solution and a regenerated organic phase.

[0039] The regenerated organic phase was reused five times according to the above steps. The oil contents of the raffinate were 3 mg / L, 3.5 mg / L, 4 mg / L, 4.6 mg / L, and 4.8 mg / L, respectively; and the extraction rates were 99.8%, 99.6%, 99.5%, 99.3%, 99.4%, and 99.6%, respectively.

[0040] Example 2:

[0041] (1) dissolving the acidic extractant P507 in kerosene to obtain a 1.0 mol / L P507 kerosene solution;

[0042] (2) adding a 9 mol / L sodium hydroxide solution to a 1.0 mol / L LP507 kerosene solution at a rate of 15.0 mL / min to saponify the obtained saponified organic phase, the degree of saponification of which was 10%;

[0043] (3) Add a Span80 kerosene solution with a concentration of 80 g / L of Span80 to the obtained saponified organic phase, preferably with a stirring speed of 120 rpm, to obtain a blended organic phase in which the content of Span80 is 6%.

[0044] (4) The resulting blended organic phase was mixed with a rare earth ion-containing solution for extraction, and the mixture was allowed to stand for phase separation to obtain a raffinate and a rare earth ion-loaded organic phase. The rare earth ion concentration in the aqueous solution was 800 mg / L, the pH value of the aqueous solution was 2, the temperature of the aqueous solution was 30°C, the stirring speed was 150 rpm, and the volume ratio of the blended organic phase to the rare earth-containing aqueous solution used for extraction was 1:2. The oil content in the raffinate was determined to be 6 mg / L, and the rare earth extraction yield was 99.3%.

[0045] (5) The rare earth ion-loaded organic phase is mixed with a 5 mol / L hydrochloric acid solution for stripping to obtain a rare earth-rich aqueous solution and a regenerated organic phase.

[0046] The regenerated organic phase was reused five times according to the above steps. The oil contents of the raffinate were 5 mg / L, 6.5 mg / L, 5 mg / L, 5.6 mg / L, and 5.8 mg / L, respectively; and the extraction rates were 99.5%, 99.6%, 99.3%, 99.4%, 99.2%, and 99.9%, respectively.

[0047] Example 3:

[0048] (1) dissolving the acidic extractant P507 in kerosene to obtain a 0.5 mol / L P507 kerosene solution;

[0049] (2) A sodium hydroxide solution with a concentration of 6 mol / L was added dropwise to a 0.5 mol / L LP507 kerosene solution at a rate of 20.0 mL / min to perform saponification, and the obtained saponified organic phase had a saponification degree of 6%.

[0050] (3) Add a kerosene solution of Span 80 having a concentration of 50 g / L to the obtained saponified organic phase, preferably with a stirring speed of 180 rpm, to obtain a blended organic phase in which the content of Span 80 is 3%.

[0051] (4) The resulting blended organic phase was mixed with a rare earth ion-containing solution for extraction, and the mixture was allowed to stand for phase separation to obtain a raffinate and a rare earth ion-loaded organic phase. The rare earth ion concentration in the aqueous solution was 1200 mg / L, the pH value of the aqueous solution was 2, the temperature of the aqueous solution was 25°C, the stirring speed was 130 rpm, and the volume ratio of the blended organic phase to the rare earth-containing aqueous solution used for extraction was 5:1. The oil content in the raffinate was determined to be 8 mg / L, and the rare earth extraction yield was 98.3%.

[0052] (5) The rare earth ion-loaded organic phase is mixed with a hydrochloric acid solution having a concentration of 7 mol / L for stripping to obtain a rare earth-rich aqueous solution and a regenerated organic phase.

[0053] The regenerated organic phase was reused five times according to the above steps. The oil contents of the raffinate were 7 mg / L, 7.5 mg / L, 7 mg / L, 5.6 mg / L, and 7.8 mg / L, respectively; and the extraction rates were 98.9%, 99.0%, 99.1%, 99.1%, 99.2%, and 99.9%, respectively.

[0054] Example 4:

[0055] (1) dissolving the acidic extractant P507 in kerosene to obtain a 0.2 mol / L P507 kerosene solution;

[0056] (2) A sodium hydroxide solution with a concentration of 6 mol / L was added dropwise to a 0.2 mol / L LP507 kerosene solution at a rate of 20.0 mL / min to perform saponification, and the obtained saponified organic phase had a saponification degree of 3%.

[0057] (3) Add a kerosene solution of Span 80 having a concentration of 30 g / L to the obtained saponified organic phase, preferably at a stirring speed of 180 rpm, to obtain a blended organic phase in which the content of Span 80 is 2%.

[0058] (4) The resulting blended organic phase was mixed with a rare earth ion-containing solution for extraction, and the mixture was allowed to stand for phase separation to obtain a raffinate and a rare earth ion-loaded organic phase. The rare earth ion concentration in the aqueous solution was 100 mg / L, the pH value of the aqueous solution was 3, the temperature of the aqueous solution was 15°C, the stirring speed was 150 rpm, and the volume ratio of the blended organic phase to the rare earth-containing aqueous solution used for extraction was 10:1. The oil content in the raffinate was determined to be 5 mg / L, and the rare earth extraction yield was 99.3%.

[0059] (5) The rare earth ion-loaded organic phase is mixed with a 4 mol / L hydrochloric acid solution for stripping to obtain a rare earth-rich aqueous solution and a regenerated organic phase.

[0060] The regenerated organic phase was reused five times according to the above steps. The oil contents of the raffinate were 5 mg / L, 5.5 mg / L, 4.8 mg / L, 5.6 mg / L, and 5.7 mg / L, respectively; and the extraction rates were 99.9%, 99.8%, 99.8%, 99.8%, 99.4%, and 99.9%, respectively.

[0061] Example 5:

[0062] (1) dissolving the amine extractant N1923 in kerosene, wherein the volume ratio of N1923 to kerosene is 1:4;

[0063] (2) A 30 g / L Span 80 kerosene solution was added to the obtained N1923 kerosene solution, preferably at a stirring speed of 180 rpm, to obtain a blended organic phase in which the Span 80 content was 1.5%.

[0064] (3) The resulting blended organic phase was mixed with a rare earth ion-containing solution for extraction, and the mixture was allowed to stand for phase separation to obtain a raffinate and a rare earth ion-loaded organic phase. The rare earth ion concentration in the aqueous solution was 100 mg / L, the pH value of the aqueous solution was 4, the temperature of the aqueous solution was 20°C, the stirring speed was 150 rpm, and the volume ratio of the blended organic phase to the rare earth-containing aqueous solution used for extraction was 2:1. The oil content in the raffinate was determined to be 3 mg / L, and the rare earth extraction yield was 99.3%.

[0065] (4) The organic phase loaded with rare earth ions is stripped with 5 mol / L 60% (NH4Cl) + 40% (HCl) as a stripping agent to obtain a rare earth-rich aqueous solution and a regenerated organic phase.

[0066] The regenerated organic phase was reused five times according to the above steps. The oil contents of the raffinate were 3 mg / L, 3.5 mg / L, 3.8 mg / L, 3.6 mg / L, and 3.7 mg / L, respectively; and the extraction rates were 99.5%, 99.6%, 99.8%, 99.8%, 99.5%, and 99.3%, respectively.

[0067] Example 6:

[0068] (1) The extractants P507 and N235 were dissolved in kerosene to form a synergistic extraction system. The concentration of P507 in the synergistic extraction system was 1.5 mol / L, and the concentration of N235 was 0.3 mol / L.

[0069] (2) Adding a 25 g / L Span 80 kerosene solution to the obtained synergistic extraction system, preferably at a stirring speed of 180 rpm, to obtain a blended organic phase, wherein the content of Span 80 is 1% by weight of the extractant in the synergistic extraction system.

[0070] (3) The resulting blended organic phase was mixed with a rare earth ion-containing solution for extraction, and the mixture was allowed to stand for phase separation to obtain a raffinate and a rare earth ion-loaded organic phase. The rare earth ion concentration in the aqueous solution was 80 mg / L, the pH value of the aqueous solution was 4, the temperature of the aqueous solution was 150°C, the stirring speed was 150 rpm, and the volume ratio of the blended organic phase to the rare earth-containing aqueous solution used for extraction was 2:1. The oil content in the raffinate was determined to be 4.5 mg / L, and the rare earth extraction yield was 99.5%.

[0071] (4) The rare earth ion-loaded organic phase is mixed with 3 mol / L hydrochloric acid for back extraction to obtain a rare earth-rich aqueous solution and a regenerated organic phase.

[0072] The regenerated organic phase was reused five times according to the above steps. The oil contents of the raffinate were 4 mg / L, 4.5 mg / L, 4.8 mg / L, 4.6 mg / L, and 4.7 mg / L, respectively. The extraction rates were 99.1%, 99.3%, 99.4%, 99.4%, 99.1%, and 99.2%, respectively.

[0073] Using the methods described in Examples 1-6, it was found that the oil content of the raffinate was consistently below 10 mg / L, while the extraction rate was as high as 99.8%. The method provided herein for preventing organic phase dissolution loss during rare earth extraction can effectively prevent organic phase dissolution loss during rare earth extraction; in other words, this method can effectively improve resource utilization, save costs, and prevent ecological pollution. Furthermore, this method has no effect on the rare earth extraction rate.

[0074] Comparative Example 1: No Span80 added

[0075] (1) dissolving the acidic extractant P507 in kerosene to obtain a 0.5 mol / L P507 kerosene solution;

[0076] (2) A sodium hydroxide solution with a concentration of 6 mol / L was added dropwise to a 0.5 mol / L LP507 kerosene solution at a rate of 20.0 mL / min to perform saponification, and the obtained saponified organic phase had a saponification degree of 6%.

[0077] (3) The saponified organic phase was mixed with a rare earth ion-containing solution for extraction, and the mixture was allowed to stand for phase separation to obtain a raffinate and a rare earth ion-loaded organic phase. The rare earth ion concentration in the aqueous solution was 1200 mg / L, the pH value of the aqueous solution was 2, the temperature of the aqueous solution was 25°C, the stirring speed was 130 rpm, and the volume ratio of the saponified organic phase to the rare earth-containing aqueous solution used for extraction was 5:1. The oil content in the raffinate was determined to be 65 mg / L, and the rare earth extraction yield was 98.2%.

[0078] (4) The rare earth ion-loaded organic phase is mixed with a hydrochloric acid solution having a concentration of 7 mol / L for stripping to obtain a rare earth-rich aqueous solution and a regenerated organic phase.

[0079] The regenerated organic phase was reused five times according to the above steps. The oil contents of the raffinate were 63 mg / L, 65 mg / L, 67 mg / L, 58 mg / L, and 60 mg / L, respectively; and the extraction rates were 98.4%, 99.1%, 99.0%, 99.3%, 99.2%, and 99.5%, respectively.

[0080] Comparative Example 1 is a method without the addition of Span 80. By comparing Comparative Example 1 with the Example, it was found that the oil content of the raffinate in the comparative example was 63 mg / L, 65 mg / L, 67 mg / L, 58 mg / L, and 60 mg / L, respectively; this shows that Span 80 plays an important role in preventing the dissolution loss of the organic phase during the rare earth extraction process.

[0081] Comparative Example 2: The amount of Span80 added is 20% of the extractant

[0082] (1) dissolving the acidic extractant P507 in kerosene to obtain a 0.2 mol / L P507 kerosene solution;

[0083] (2) A sodium hydroxide solution with a concentration of 6 mol / L was added dropwise to a 0.2 mol / L LP507 kerosene solution at a rate of 20.0 mL / min to perform saponification, and the obtained saponified organic phase had a saponification degree of 3%.

[0084] (3) Add a kerosene solution of Span 80 having a concentration of 30 g / L to the obtained saponified organic phase, preferably at a stirring speed of 180 rpm, to obtain a blended organic phase in which the content of Span 80 is 20%.

[0085] (4) The resulting blended organic phase was mixed with a rare earth ion-containing solution for extraction, and the mixture was allowed to stand for phase separation to obtain a raffinate and a rare earth ion-loaded organic phase. The rare earth ion concentration in the aqueous solution was 100 mg / L, the pH value of the aqueous solution was 3, the temperature of the aqueous solution was 15°C, the stirring speed was 150 rpm, and the volume ratio of the blended organic phase to the rare earth-containing aqueous solution used for extraction was 10:1. The oil content in the raffinate was determined to be 90 mg / L, and the rare earth extraction yield was 80.5%.

[0086] (5) The rare earth ion-loaded organic phase is mixed with a 4 mol / L hydrochloric acid solution for stripping to obtain a rare earth-rich aqueous solution and a regenerated organic phase.

[0087] The regenerated organic phase was reused five times according to the above steps. The oil contents of the raffinate were 95 mg / L, 100 mg / L, 90 mg / L, 86 mg / L, and 91 mg / L, respectively; and the extraction rates were 79.9%, 82.8%, 81.8%, 80.8%, 79.4%, and 79.9%, respectively.

[0088] Comparative Example 2 is a method in which the addition amount of Span 80 is 20% of the mass of the extractant. By comparing Comparative Example 2 with the example, it is found that the oil content of the raffinate in Comparative Example 2 is 95 mg / L, 100 mg / L, 90 mg / L, 86 mg / L, and 91 mg / L, respectively; this shows that the addition amount of Span 80 plays an important role in preventing the dissolution loss of the organic phase during the rare earth extraction process.

[0089] Fourier transform infrared spectroscopy was used to characterize the different organic phases. Figure 1 As shown, different organic phases are at 1800-1100 cm -1 Infrared spectra within a wavelength range

[0090] In the figure, a is a 1 mol / L P507-kerosene solution, b is a 1.0 mol P507-kerosene solution with a saponification degree of 5%, and c is a 1.0 mol / L P507-kerosene solution containing 6% span 80 and a saponification degree of 5%.

[0091] pass Figure 1 It can be found in the spectrum at 1742cm -1 A peak appears at , and this peak is only present in the organic phase after Span 80 addition. This peak is likely due to the C=O stretching vibration formed by the binding of Span 80 and P507. The addition of Span 80 further alters the association state of the organic phase, partially strengthening the bond energy and stabilizing the structure, preventing the dissolution of the P507 molecules.

[0092] Based on the above, the present application provides a method for preventing the dissolution loss of the organic phase during the rare earth extraction process through the mutual coordination and synergistic effect of the formula and method.

[0093] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0094] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0095] In this application, unless otherwise expressly specified or defined, the terms "installed," "connected," "connected," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or mutual communication; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0096] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0097] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A method for preventing organic phase dissolution loss during rare earth extraction, characterized in that: include: (1) dissolving the extractant in a predetermined diluent to obtain an organic extraction solution; (2) mixing the organic extraction solution in step (1) with an inorganic alkali solution to obtain a saponified organic phase; (3) stirring and mixing the diluted organic solution of anhydrous sorbitan fatty acid ester with the organic extraction solution prepared in step (1) or the saponified organic phase prepared in step (2) or the regenerated organic phase obtained in step (5) to obtain a blended organic phase; (4) extracting the blended organic phase prepared in step (3) with the rare earth ion solution, allowing the mixture to stand for phase separation to obtain a raffinate and an organic phase loaded with rare earth ions; (5) The rare earth ion-loaded organic phase obtained in step (4) is mixed with a hydrochloric acid solution and stripped to obtain a rare earth-rich aqueous solution and a regenerated organic phase: Before step (3), the following steps are also included: diluting the sorbitan fatty acid ester into an organic solvent to obtain a diluted organic solution of the sorbitan fatty acid ester; The added amount of the sorbitan fatty acid ester is 1% to 15% of the mass of the extractant in the organic extraction solution.

2. The method for preventing organic phase dissolution loss in a rare earth extraction process according to claim 1, wherein: Step (2) specifically comprises dissolving an inorganic alkali solution in water to obtain an inorganic alkali aqueous solution; and then dripping the solution into the organic extraction solution prepared in step (1) for saponification; the dripping speed of the inorganic alkali aqueous solution is 0.05 to 20.0 mL / min.

3. The method for preventing organic phase dissolution loss in a rare earth extraction process according to claim 2, wherein: The concentration of the inorganic alkali aqueous solution is 1.0 to 12.0 mol / L; The concentration of the hydrochloric acid solution in step (5) is 1.0 to 12.0 mol / L.

4. The method for preventing organic phase dissolution loss in a rare earth extraction process according to claim 1, wherein: The extractant is an acidic extractant, an amine extractant or a synergistic extraction system; The acidic extractant is one or a combination of two or more of P507, P204, C272, and cyclohexane acid; The amine extractant is one or a combination of N235, N236, and N1923; The synergistic extraction system is one or a combination of P507-TBP, P204-TBP, C272-TBP, P507-N235, P507-P204, P507-C272, P507-N263, P204-N263, P204-N235, C272-N263, and C272-N235.

5. The method for preventing organic phase dissolution loss in a rare earth extraction process according to claim 1, wherein: The inorganic alkali solution is sodium hydroxide, potassium hydroxide or ammonia water.

6. The method for preventing organic phase dissolution loss in a rare earth extraction process according to claim 1, wherein: The concentration of sorbitan fatty acid ester in the diluted organic solution of sorbitan fatty acid ester is 25 to 250 g / L; The stirring speed during the stirring and mixing in step (3) is 100 to 200 rpm.

7. The method for preventing organic phase dissolution loss in a rare earth extraction process according to claim 1, wherein: During extraction, the stirring speed is 50-300 rpm, and the volume ratio of the organic phase to the rare earth ion-containing solution is 50:1-1:0.

5.

8. The method for preventing organic phase dissolution loss in a rare earth extraction process according to claim 7, wherein: In the step (3), the pH value of the rare earth ion solution is 2 to 4; and the total concentration of the rare earth ion solution is 0.08 to 2 g / L.

9. The method for preventing organic phase dissolution loss in a rare earth extraction process according to claim 1, wherein: The preset diluent is an aliphatic hydrocarbon or aromatic hydrocarbon diluent having a boiling point above 200° C. under normal pressure.

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