阅读说明：本技术 一种硫酸铯和硫酸铷的制备方法 (preparation method of cesium sulfate and rubidium sulfate ) 是由 席文龙 周慧瑶 彭平 于 2019-10-10 设计创作，主要内容包括：本发明涉及矿物提取技术领域,具体涉及一种硫酸铯和硫酸铷的制备方法。本发明对传统的铷铯提取方法进行改进,先从沉锂废渣中以特定配比的t-BAMBP和260#号溶剂油为萃取溶液,采用多级萃取技术萃取铯,并获得硫酸铯纯品,产品纯度高达99.9％以上；然后从铯提取的萃余液中采用特定配比的t-BAMBP和正己烷为萃取溶液,能对铷和钾进行分离,获得高纯度的硫酸铷,纯度达到99.9％以上。制备过程涉及的有机溶剂种类少,利于废液处理和回收套用。(The invention relates to the technical field of mineral extraction, and particularly relates to a preparation method of cesium sulfate and rubidium sulfate. The invention improves the traditional rubidium and cesium extraction method, firstly, t-BAMBP and No. 260 solvent oil with specific proportion are taken as extraction solution from lithium precipitation waste residue, a multistage extraction technology is adopted to extract cesium, and a pure cesium sulfate product is obtained, wherein the purity of the product is as high as more than 99.9%; and then, the raffinate extracted from cesium adopts t-BAMBP and n-hexane in a specific ratio as an extraction solution, and rubidium and potassium can be separated to obtain high-purity rubidium sulfate, wherein the purity is over 99.9%. The preparation process involves few kinds of organic solvents, and is beneficial to waste liquid treatment and recycling.)

1. A preparation method of cesium sulfate and rubidium sulfate is characterized by comprising the following steps:

(1) Pretreatment: adding 3-5 times of water by mass into the lithium precipitation waste residue f, heating at 70-85 ℃ until the lithium precipitation waste residue f is completely dissolved, cooling to room temperature, filtering, and adjusting the pH of the filtrate to 8-11 by using 0.8-1 mol/L NaOH to obtain a mixed solution g;

(2) separating cesium and rubidium by taking t-BAMBP as an extracting agent and 260# solvent oil as a diluent to extract cesium in the mixed solution g, wherein the volume ratio of t-BAMBP to 260# is 1 (3-5), the ratio of organic phase to aqueous phase flow is (4-6): 1, the contact time is 5min to 10min, the extraction stage number is 8-10, the washing solution is deionized water, the ratio of organic phase to aqueous phase flow is (5-7): 3, the washing stage number is 8-10, performing back extraction by using 25 wt% -35 wt% of sulfuric acid, the ratio of organic phase to aqueous phase flow is 1 (4-6), the contact time is 5min to 10min, the back extraction stage number is 2-4, and the back extraction solution is subjected to evaporation and crystallization and is calcined at 500-550 ℃ for 2 h-2.5 h to obtain Cs ₂ SO ₄;

(3) separating rubidium from potassium, namely taking the residual phase after cesium extraction as a rubidium extraction raw material liquid, taking t-BAMBP as an extracting agent, taking n-hexane as a diluent, extracting the cesium with the t-BAMBP and the n-hexane in a volume ratio of 1 (5-6), wherein the extraction flow ratio of an organic phase to an aqueous phase is 1 (2-4), the contact time is 5min to 10min, the extraction stage number is 6-8, washing liquid is deionized water, the flow ratio of the organic phase to the aqueous phase is (3-5): 1, the stage number is 7-9, performing back extraction on rubidium by adopting 25 wt% -35 wt% of sulfuric acid, the flow ratio of the organic phase to the aqueous phase is (10-12): 1, the contact time is 5min to 10min, the back extraction stage number is 2-3, evaporating and crystallizing the back extraction liquid, and calcining the back extraction liquid at 500-550 ℃ for 2 h-2.5 h to obtain an Rb ₂.

2. The method for preparing cesium sulfate and rubidium sulfate according to claim 1, wherein the step (1) of preparing lithium precipitation waste residue f comprises the following steps:

a. grinding and activating: taking coarsely crushed lepidolite, controlling the particle size below 80 meshes, adding water with the mass 2-3.5 times of that of the lepidolite into the lepidolite to prepare slurry, adding polyethylene glycol accounting for 2.5-5% of the weight of the slurry into the slurry after the slurry is prepared, and then carrying out wet superfine grinding on the materials for 8-10 hours to obtain a fine grinding material a;

b. ultrasonic acidification leaching: adding a sulfuric acid solution into the fine grinding material a, uniformly mixing the fine grinding material and the sulfuric acid solution according to the mass ratio of 1 (3-5), leaching under the condition of ultrasonic waves, setting the ultrasonic power at 100-150W, the ultrasonic frequency at 20-28 KHz, the temperature at 70-100 ℃, and the leaching time at 10-15 min, filtering and collecting a leaching solution b;

c. alkalization and impurity removal: adding NaOH solution into the leaching solution b, adjusting the pH value of the solution to 10-12, then adding a small amount of activated carbon into the solution, stirring and reacting for 10-30 min to remove impurities, and filtering after the reaction is finished to obtain impurity-removed solution c;

d. Neutralizing and concentrating, namely adding concentrated H ₂ SO ₄ into the impurity-removed solution c, adjusting the pH value of the solution to 6-7, evaporating and concentrating the solution to 45-55% of the volume of the original solution, and naturally cooling to room temperature to obtain a concentrated solution d;

e. secondary impurity removal: and (4) freezing the concentrated solution d to-10 ℃ to precipitate sodium, potassium, rubidium and cesium alum, and filtering and separating to obtain a mother solution e and lithium precipitation waste residue f.

3. the method for preparing cesium sulfate and rubidium sulfate as claimed in claim 2, wherein the concentration of sulfuric acid in step b is 35 wt% to 55 wt%.

4. the method for preparing cesium sulfate and rubidium sulfate as claimed in claim 2, wherein the concentration of NaOH solution in step c is 15 wt% -25 wt%.

5. The method for preparing cesium sulfate and rubidium sulfate as claimed in claim 2, wherein the amount of the activated carbon added in step c is 0.2-0.8% of the solution mass.

Technical Field

The invention relates to the technical field of mineral extraction, and particularly relates to a preparation method of cesium sulfate and rubidium sulfate.

background

Rubidium and cesium play an important role in a variety of high and new technical fields such as aerospace, atomic energy, biology, energy and the like due to their unique properties, and the application and development of rubidium and cesium are receiving more and more extensive attention, and the extraction, separation and industrial production of rubidium and cesium also become hot spots of research of people.

Rubidium and cesium are generally associated with other minerals and often coexist with a plurality of metal elements such as lithium and potassium. Lepidolite contains rich elements such as lithium, potassium, rubidium, cesium and the like. When the lepidolite is treated by sulfuric acid, a mixed alum byproduct containing rubidium, cesium and potassium can be obtained, lithium extraction of lithium salt is often ignored by lithium manufacturers taking the lepidolite as a raw material in China, and the obtained rubidium and cesium byproduct is often sold at a low base price, so that resource waste is caused.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a preparation method of cesium sulfate and rubidium sulfate, which adopts t-BAMBP, No. 260 solvent oil, t-BAMBP and n-hexane in a specific ratio as extraction solutions, and can better separate rubidium, cesium and potassium in the solutions; high-purity rubidium sulfate and cesium sulfate are obtained, the preparation process is simple, the related organic solvents are few in types, and waste liquid treatment and recycling are facilitated.

The preparation method of cesium sulfate and rubidium sulfate comprises the following steps:

(1) Pretreatment: adding 3-5 times of water by mass into the lithium precipitation waste residue f, heating at 70-85 ℃ until the lithium precipitation waste residue is completely dissolved, cooling to room temperature, filtering, and adjusting the pH of the filtrate to 8-11 by using 0.8-1 mol/L NaOH to obtain a mixed solution g;

(2) Separating cesium and rubidium by taking t-BAMBP as an extracting agent and 260# solvent oil as a diluent to extract cesium in the mixed solution g, wherein the volume ratio of t-BAMBP to 260# is 1 (3-5), the ratio of organic phase to aqueous phase flow is (4-6): 1, the contact time is 5min to 10min, the extraction stage number is 8-10, the washing solution is deionized water, the ratio of organic phase to aqueous phase flow is (5-7): 3, the washing stage number is 8-10, performing back extraction by using 25 wt% -35 wt% of sulfuric acid, the ratio of organic phase to aqueous phase flow is 1 (4-6), the contact time is 5min to 10min, the back extraction stage number is 2-4, and the back extraction solution is subjected to evaporation and crystallization and is calcined at 500-550 ℃ for 2 h-2.5 h to obtain Cs ₂ SO ₄;

(3) Separating rubidium from potassium, namely taking the residual phase after cesium extraction as a rubidium extraction raw material liquid, taking t-BAMBP as an extracting agent, taking n-hexane as a diluent, extracting the cesium with the t-BAMBP and the n-hexane in a volume ratio of 1 (5-6), wherein the extraction flow ratio of an organic phase to an aqueous phase is 1 (2-4), the contact time is 5min to 10min, the extraction stage number is 6-8, washing liquid is deionized water, the flow ratio of the organic phase to the aqueous phase is (3-5): 1, the stage number is 7-9, performing back extraction on rubidium by adopting 25 wt% -35 wt% of sulfuric acid, the flow ratio of the organic phase to the aqueous phase is (10-12): 1, the contact time is 5min to 10min, the back extraction stage number is 2-3, evaporating and crystallizing the back extraction liquid, and calcining the back extraction liquid at 500-550 ℃ for 2 h-2.5 h to obtain an Rb ₂.

Preferably, the preparation of the lithium precipitating waste residue f comprises the following steps:

a. grinding and activating: taking coarsely crushed lepidolite, controlling the particle size below 80 meshes, adding water with the mass 2-3.5 times of that of the lepidolite into the lepidolite to prepare slurry, adding polyethylene glycol accounting for 2.5-5% of the weight of the slurry into the slurry after the slurry is prepared, and then carrying out wet superfine grinding on the materials for 8-10 hours to obtain a fine grinding material a;

b. Ultrasonic acidification leaching: adding a sulfuric acid solution into the fine grinding material a, uniformly mixing the fine grinding material and the sulfuric acid solution according to the mass ratio of 1 (3-5), leaching under the condition of ultrasonic waves, setting the ultrasonic power at 100-150W, the ultrasonic frequency at 20-28 KHz, the temperature at 70-100 ℃, and the leaching time at 10-15 min, filtering and collecting a leaching solution b;

c. Alkalization and impurity removal: adding NaOH solution into the leaching solution b, adjusting the pH value of the solution to 10-12, then adding a small amount of activated carbon into the solution, stirring and reacting for 10-30 min to remove impurities, and filtering after the reaction is finished to obtain impurity-removed solution c;

d. neutralizing and concentrating, namely adding concentrated H ₂ SO ₄ into the impurity-removed solution c, adjusting the pH value of the solution to 6-7, evaporating and concentrating the solution to 45-55% of the volume of the original solution, and naturally cooling to room temperature to obtain a concentrated solution d;

e. secondary impurity removal: freezing the concentrated solution d to-10 ℃ to precipitate sodium, potassium, rubidium and cesium alum, and filtering and separating to obtain a mother solution e and precipitated lithium waste residue f; (ii) a

Preferably, the concentration of the sulfuric acid in the step (2) is 35 to 55 weight percent.

Preferably, the concentration of the NaOH solution in the step (3) is 15 wt% to 25 wt%.

Preferably, the adding amount of the activated carbon in the step (3) is 0.2-0.8 per mill of the mass of the solution.

Compared with the prior art, the invention has the advantages that:

1. the invention improves the traditional rubidium and cesium extraction method, firstly, t-BAMBP and No. 260 solvent oil with specific proportion are taken as extraction solution from lithium precipitation waste residue, a multistage extraction technology is adopted to extract cesium, and a pure cesium sulfate product is obtained, wherein the purity of the product is as high as more than 99.9%; and then, the raffinate extracted from cesium adopts t-BAMBP and n-hexane in a specific ratio as an extraction solution, and rubidium and potassium can be separated to obtain high-purity rubidium sulfate, wherein the purity is over 99.9%. The preparation process involves few kinds of organic solvents, and is beneficial to waste liquid treatment and recycling.

2. the invention also provides a preparation process of the lithium extraction waste residue, and the wet grinding is carried out on the lepidolite by adding the ethylene glycol into the lepidolite and the applicant finds that the lepidolite can be promoted to be modified by long-time grinding, so that the high-temperature calcining process in the prior art is avoided, a large amount of energy can be saved, and the environment is protected; the ground fine materials are leached by sulfuric acid assisted by ultrasound, so that the acidification leaching time is shortened, and the materials are sufficiently acidified. By adding the activated carbon into the leachate, the activated carbon has strong adsorption capacity, and can be added as an adsorbent to adsorb gas impurities generated by reaction and not absorbed, so that the emission of harmful gases is reduced.

Detailed Description

the invention discloses a process method for preparing cesium sulfate and rubidium sulfate, and a person skilled in the art can use the contents to reference the text and appropriately improve process parameters to realize the process. It is expressly intended that all such similar substitutes and modifications which would be obvious to one skilled in the art are deemed to be included in the invention. While the methods and applications of this invention have been described in terms of preferred embodiments, it will be apparent to those of ordinary skill in the art that variations and modifications in the methods and applications described herein, as well as other suitable variations and combinations, may be made to implement and use the techniques of this invention without departing from the spirit and scope of the invention.

Unless otherwise specified, the raw materials and auxiliary materials according to the present invention are all commercially available products and are commercially available.

The invention adopts tantalum niobium tailings lepidolite in Yichun Jiangxi, and the physicochemical properties of the lepidolite are as follows: the appearance is white; has glass luster or pearl luster; scaly, relative density of 2.8-2.9. The main components of the chemical composition in the lithium cloud are as follows:

Li2O

K2O

Na2O

Al2O3

SiO2

Fe2O3

Rb2O

Cs2O

F

4.1％

8.2％

0.9％

23.2％

53.7％

0.2％

1.3％

0.24％

4.1％