阅读说明：本技术 一种氟铝酸铷铯铝钎剂及其制备方法 (Rubidium and cesium fluoroaluminate aluminum soldering flux and preparation method thereof ) 是由 彭秋华 左青松 陈凯 于 2021-09-03 设计创作，主要内容包括：本发明公开了一种氟铝酸铷铯铝钎剂的制备方法,用从锂云母中提取的钾铷铯混合矾,通过加石灰将钾铷铯混合矾转化为钾铷铯的硫酸盐溶液,再经过萃取,将硫酸盐溶液中的铷和铯一并萃取出来,去除了其中的钾和其它杂质,通过二氧化碳反萃,得到铷铯的碳酸盐溶液,通过浓缩结晶得到铷铯混合碳酸盐,将铷铯混合碳酸盐与分析纯氢氧化铝以一定配比加入反应釜,加水或母液搅匀,逐步加入氢氟酸,控制合适的反应温度,得到氟铝酸铷铯结晶,通过离心分离,烘干,粉碎,得到符合要求的氟铝酸铷铯产品。本发明以钾铷铯混合矾为原料,采用萃取剂共萃铷铯从而将其中的钾和其它杂质去除,得到比较纯的铷铯混合碳酸盐；直接与氢氧化铝和氢氟酸反应获得氟铝酸铷铯。(The invention discloses a preparation method of a rubidium-cesium fluoroaluminate aluminum soldering flux, which comprises the steps of mixing potassium, rubidium and cesium extracted from lepidolite with alum, adding lime to convert the potassium, rubidium and cesium mixed alum into a sulfate solution of potassium, rubidium and cesium, extracting to extract rubidium and cesium in the sulfate solution together, removing potassium and other impurities, performing back extraction by carbon dioxide to obtain a rubidium-cesium carbonate solution, performing concentration and crystallization to obtain a rubidium-cesium mixed carbonate, adding the rubidium-cesium mixed carbonate and analytically pure aluminum hydroxide into a reaction kettle according to a certain ratio, adding water or mother liquor to stir uniformly, adding hydrofluoric acid step by step, controlling a proper reaction temperature to obtain a rubidium-cesium fluoroaluminate crystal, performing centrifugal separation, drying and crushing to obtain a rubidium-cesium fluoroaluminate product meeting the requirements. According to the invention, the mixed vanadium of potassium, rubidium and cesium is used as a raw material, and an extracting agent is adopted to co-extract rubidium and cesium so as to remove potassium and other impurities in the mixed vanadium, rubidium and cesium, so that relatively pure mixed rubidium and cesium carbonate is obtained; directly reacting with aluminum hydroxide and hydrofluoric acid to obtain rubidium and cesium fluoroaluminate.)

1. A rubidium and cesium fluoroaluminate brazing flux is characterized by comprising 45-50% Rb, 9-10% Cs, 10-13% Al, 27-35F, less than 0.01% Li, less than 0.01% K, less than 0.05% Na, less than 0.01% Ca, less than 0.005% Ba, and the balance of oxygen and other impurities.

2. A method for preparing rubidium-caesium fluoroaluminate aluminum brazing flux comprises the steps of mixing potassium, rubidium and caesium with vanadium extracted from lepidolite, adding lime to convert the potassium, rubidium and caesium mixed vanadium into potassium, rubidium and caesium sulfate solution, extracting to extract rubidium and caesium in the sulfate solution together, removing potassium and other impurities, performing carbon dioxide back extraction to obtain rubidium-caesium carbonate solution, performing concentration crystallization to obtain rubidium-caesium mixed carbonate, adding the rubidium-caesium mixed carbonate and analytically pure aluminum hydroxide into a reaction kettle in a certain ratio, adding water or mother liquor to stir uniformly, adding hydrofluoric acid step by step, controlling a proper reaction temperature, obtaining rubidium-caesium fluoroaluminate crystals, performing centrifugal separation, drying and crushing to obtain a rubidium-caesium fluoroaluminate product meeting requirements.

3. The method of claim 2, wherein the steps of preparing said rubidium-cesium aluminum flux fluoroaluminate include:

(1) potassium, rubidium and cesium mixed alum conversion: reacting potassium, rubidium and cesium mixed alum with lime to convert the mixed alum into a sulfate solution of potassium, rubidium and cesium;

(2) liquid-solid separation: carrying out filter pressing on the converted materials, washing residues with pure water, using the washing liquid for conversion reaction, and carrying out filter pressing to obtain a pure carbonate solution of potassium, rubidium and cesium;

(3) and (3) performing co-extraction of rubidium and cesium: co-extracting the sulfate solution of potassium, rubidium and cesium by using an extracting agent, and performing back extraction by using carbon dioxide to obtain a carbonate solution of rubidium and cesium;

(4) concentration and crystallization: concentrating and crystallizing the solution to obtain mixed carbonate solid of rubidium and cesium;

(5) synthesis of rubidium and cesium fluoroaluminates: adding rubidium and cesium mixed carbonate and analytically pure aluminum hydroxide into a reaction kettle according to a proper proportion, adding pure water or mother liquor, and uniformly stirring;

(6) and (3) gradually adding hydrofluoric acid into the reaction kettle, and continuing stirring until a qualified rubidium-cesium fluoroaluminate product is generated after the reaction reaches the end point.

4. The method of claim 3, wherein in step (1), the ratio of potassium, rubidium and cesium mixed alum to lime is determined to be 1: 0.4, the reaction temperature is 80-90 ℃, and the reaction time is 1 hour.

5. The method of claim 3, wherein in step (3), the removal rate of potassium in the strip solution after co-extraction is greater than 99.9%.

6. The method of claim 3, wherein in step (5), the ratio of rubidium and cesium mixed carbonate to analytically pure aluminum hydroxide is 1: (0.50-0.60).

7. The method of claim 3, wherein in step (6), the final pH of the hydrofluoric acid is controlled to be 6-8, and the hydrofluoric acid is added to reach the final pH.

8. The method of claim 3, wherein in step (6), the acid addition time is controlled within 2 hours, and the reaction time is continued for 2-3 hours after the acid addition.

9. The method of claim 3, wherein in step (6), the reaction temperature is controlled to be 80 ℃ to 90 ℃.

10. The method of claim 3, wherein in step (6), the resultant mixture is cooled to 40 ℃ -45 ℃.

Technical Field

The invention relates to the technical field of brazing materials, in particular to a rubidium and cesium fluoroaluminate aluminum brazing flux and a preparation method thereof.

Background

Aluminum brazing is one of the important methods for connecting aluminum and aluminum alloy and aluminum and copper alloy, and compared with fusion welding, the method has the advantages of small workpiece deformation, high dimensional precision and the like, so that the method is increasingly widely applied to the fields of aerospace, automobiles, high-speed trains, ship engineering and the like. The technology of aluminum and aluminum alloy and aluminum and copper alloy brazing has been rapidly developed in recent years, and new brazing filler metals, new brazing fluxes, new brazing process methods and new brazing equipment are continuously appeared. The brazing of aluminum refers to high-temperature aluminum brazing within the temperature range of 500-630 ℃, medium-temperature aluminum brazing at the temperature of 300-500 ℃ and low-temperature aluminum brazing below 300 ℃.

The flux plays the following roles in the brazing process: oxides on the surfaces of the brazing metal and the brazing filler metal are removed, and necessary conditions are created for the spreading of the liquid brazing filler metal on the surfaces of the brazing metal; covering the surfaces of the brazing metal and the brazing filler metal with a liquid thin layer to isolate the harmful effect of oxygen in the air on the brazing metal and the brazing filler metal; has the function of interfacial activity and improves the wetting of the liquid solder to the surface of the brazing metal. Thus, the role of the flux is of considerable importance during brazing.

The brazing flux plays the role of a film remover, a wetting agent and a covering agent in the brazing process, so that the aluminum brazing flux is one of the most important elements in the aluminum brazing process, and the development of the aluminum brazing technology is closely connected with the development of the aluminum brazing flux. Aluminum brazing flux can be classified into two major types, corrosive brazing flux and non-corrosive brazing flux, according to whether the aluminum brazing flux is corrosive or not. The corrosive aluminum soldering flux mainly refers to the traditional alkali metal and alkaline earth metal chloride soldering flux, such as aluminum soldering powder consisting of lithium chloride, sodium chloride and potassium chloride. The non-corrosive aluminum brazing flux mainly refers to fluoride (fluoride and fluoroaluminate) brazing flux, and the fluoride brazing flux is a non-corrosive and insoluble aluminum brazing flux which is rapidly developed in the later 70 th of the 20 th century. The noncorrosive aluminum brazing flux has been developed into different products of several generations and has better and better performance, for example, the first invented noncorrosive brazing flux which has a wider application is (KF-A1F 3) brazing flux, the melting temperature of the brazing flux is 558 ℃, although the brazing flux has certain advantages compared with the prior aluminum brazing flux, the use range is limited due to the fact that the melting point is still higher, the biggest defect is that the operation temperature reaches 600 ℃, and most half of aluminum alloy at the temperature cannot be used due to the fact that the overburning temperature is lower than 600 ℃, so that the brazing flux can only be used for welding of a part of aluminum alloy. The fluoroaluminate brazing flux is most applied to the existing non-corrosive brazing flux of aluminum and aluminum alloy, and is composed of potassium fluoroaluminate, rubidium fluoroaluminate or cesium fluoroaluminate independently or composed of potassium fluoroaluminate, rubidium fluoroaluminate and cesium in different proportions, so that the aluminum brazing flux has the characteristics of no corrosion, no need of cleaning residues after welding and the like. For example, the melting point of cesium fluoroaluminate is about 430 ℃, so that the cesium fluoroaluminate welding flux has a good welding effect on aluminum and aluminum alloy and also has a good welding effect on aluminum and copper alloy. However, since cesium is scarce in resources and needs to be imported from abroad, it is expensive and difficult to stably supply it for a long period of time.

The Yichun 414 mine in Jiangxi of China is rich in rubidium and also contains cesium, and the lepidolite concentrate containing 3% of lithium in the 414 mine is taken as an example, wherein the rubidium content is more than 1%, and the cesium content is lower and is about 0.2%. According to earlier mining conclusions, the optical 414 mine has 30 million tons of rubidium resources and 6 million tons of cesium resources. Also, the much more profitable lepidolite ore that is being mined also contains rubidium and cesium, and these lepidolite ores are currently being mined in large quantities for extracting lithium, while the rubidium and cesium resources that are more scarce and more valuable than lithium are essentially not utilized, and are wasted in vain.

The applicant has disclosed in the CN104625484A patent a new rubidium-cesium brazing flux, whose composition is, in terms of moles, in a molar ratio: 0.12 to 0.5 mol of rubidium fluoride, 0.12 to 0.5 mol of cesium fluoride, 0.001 to 0.2 mol of alumina, 0.001 to 0.02 mol of lithium fluoride, 0.0001 to 0.02 mol of gallium oxide, and the balance of aluminum fluoride. However, this rubidium-cesium brazing flux uses rubidium, cesium, and lithium fluorides and aluminum and gallium oxides as synthesis components, and although the melting point is lower than some other aluminum brazing fluxes and the wet spreading performance is improved, this rubidium-cesium brazing flux has the disadvantage of having a high melting point and a high cost. The invention changes the formula and the production process, so that the rubidium and cesium fluoroaluminate aluminum brazing flux has the advantages of lower melting point, lower cost and better use effect.

Disclosure of Invention

The invention provides a preparation method of a rubidium-cesium fluoroaluminate aluminum brazing flux and a rubidium-cesium fluoroaluminate aluminum brazing flux, in order to fully utilize domestic rubidium-cesium resources which can be stably supplied for a long time, particularly rubidium resources, adapt to the requirements of most aluminum alloy brazing, reduce production cost and obtain excellent brazing flux medium-temperature welding performance, although the melting point of the rubidium-cesium fluoroaluminate brazing flux is higher than that of cesium fluoroaluminate, the melting point of the rubidium-cesium-aluminum flux is lower than that of the rubidium-cesium-fluoroaluminate brazing flux formed by the joint reaction of rubidium-cesium fluoride, lithium fluoride and aluminum-gallium oxide.

The invention is realized by the following technical scheme. A rubidium and cesium fluoroaluminate brazing flux comprises 45-50% Rb, 9-10% Cs, 10-13% Al, 27-35F, less than 0.005% Li, less than 0.005% K, less than 0.05% Na, less than 0.01% Ca, less than 0.005% Ba, and the balance of O (oxygen) and other impurities.

A method for preparing rubidium-caesium fluoroaluminate aluminum brazing flux comprises the steps of mixing potassium, rubidium and caesium with vanadium extracted from lepidolite, adding lime to convert the potassium, rubidium and caesium mixed vanadium into potassium, rubidium and caesium sulfate solution, extracting to extract rubidium and caesium in the sulfate solution together, removing potassium and other impurities, performing carbon dioxide back extraction to obtain rubidium-caesium carbonate solution, performing concentration crystallization to obtain rubidium-caesium mixed carbonate, adding the rubidium-caesium mixed carbonate and analytically pure aluminum hydroxide into a reaction kettle in a certain ratio, adding water or mother liquor to stir uniformly, adding hydrofluoric acid step by step, controlling a proper reaction temperature, obtaining rubidium-caesium fluoroaluminate crystals, performing centrifugal separation, drying and crushing to obtain a rubidium-caesium fluoroaluminate product meeting requirements.

A preparation method of rubidium and cesium fluoroaluminate aluminum soldering flux comprises the following steps:

(7) potassium, rubidium and cesium mixed alum conversion: reacting potassium, rubidium and cesium mixed alum with lime to convert the mixed alum into a sulfate solution of potassium, rubidium and cesium;

(8) liquid-solid separation: carrying out filter pressing on the converted materials, washing residues with pure water, using the washing liquid for conversion reaction, and carrying out filter pressing to obtain a pure carbonate solution of potassium, rubidium and cesium;

(9) and (3) performing co-extraction of rubidium and cesium: co-extracting the sulfate solution of potassium, rubidium and cesium by using an extracting agent, and performing back extraction by using carbon dioxide to obtain a carbonate solution of rubidium and cesium;

(10) concentration and crystallization: concentrating and crystallizing the solution to obtain mixed carbonate solid of rubidium and cesium;

(11) synthesis of rubidium and cesium fluoroaluminates: adding rubidium and cesium mixed carbonate and analytically pure aluminum hydroxide into a reaction kettle according to a proper proportion, adding pure water or mother liquor, and uniformly stirring;

(12) and (3) gradually adding hydrofluoric acid into the reaction kettle, and continuing stirring until a qualified rubidium-cesium fluoroaluminate product is generated after the reaction reaches the end point.

More preferably, the rubidium/cesium fluoroaluminate product obtained in the step (6) is subjected to centrifugal separation, drying and pulverization.

Further preferably, in the step (1), the adding ratio of the potassium, rubidium and cesium mixed alum to lime is determined to be 1: 0.4, the reaction temperature is 80-90 ℃, and the reaction time is 1 hour.

Further preferably, in the step (3), the removal rate of potassium in the strip liquor after the co-extraction is more than 99.9%.

More preferably, in step (5), the mixing ratio of rubidium/cesium mixed carbonate to analytically pure aluminum hydroxide is 1: (0.50-0.60).

Further preferably, in the step (6), the end point pH value of the hydrofluoric acid is controlled to be 6-8, and the addition amount of the hydrofluoric acid is controlled to reach the end point pH.

Further preferably, in the step (6), the acid adding time is controlled within 2 hours, and the continuous reaction time after the acid is added is 2-3 hours.

Further preferably, in the step (6), the reaction temperature is controlled to 80 to 90 ℃.

Further preferably, in the step (6), the material after the reaction is completed is cooled to 40 ℃ to 45 ℃.

Further preferably, the centrifugal separation: carrying out centrifugal separation on the materials to obtain a wet product; and (4) separating the obtained mother liquor, and returning the mother liquor to the step (6) for batching.

Further preferably, the drying process is as follows: and drying the wet product by using an oven, wherein the drying temperature is controlled to be 200-220 ℃, and the drying time is controlled to be constant temperature for 2-3 hours.

Further preferably, the crushing process is as follows: crushing the dried product by using an ultrafine crusher to obtain a powdery product with required granularity, packaging, and warehousing after passing inspection; after pulverizingProduct particle size D₅₀The melting temperature of the product is controlled to be 465-485 ℃.

The invention has the following effects: rubidium and cesium resources, particularly rubidium resources, in lepidolite are fully utilized; taking mixed potassium, rubidium and cesium alum as a raw material, and co-extracting rubidium and cesium by adopting a special extracting agent so as to remove potassium and other impurities in the mixed rubidium and cesium to obtain relatively pure mixed rubidium and cesium carbonate; the rubidium-cesium fluoroaluminate product with a lower melting point is obtained through formula optimization, is suitable for brazing most of aluminum alloys and has a good effect, and the production cost of the rubidium-cesium fluoroaluminate is reduced and is lower than that of a traditional rubidium-cesium brazing flux.

Drawings

FIG. 1 is a process flow diagram of the present invention.

Detailed Description

A method for preparing rubidium and cesium fluoroaluminate aluminum brazing flux, which is characterized in that potassium, rubidium and cesium extracted from lepidolite are mixed with alum, wherein the main components of the alum are as follows:

component (A)	KAl(SO4)2·12H2O	RbAl(SO4)2·12H2O	CsAl(SO4)2·12H2O
				Content (%)	82.50～～78.20	15.22～～18.26	2.14～～2.56

The potassium, rubidium and cesium mixed alum is converted into a potassium, rubidium and cesium sulfate solution by adding lime, and the contents of potassium, rubidium and cesium in the converted sulfate solution are as follows:

component (A)	K	Rb	Cs
				Content (g/l)	20～～24.5	8～～10	1.6～～2.0

Extracting, namely extracting rubidium and cesium together to remove potassium and other impurities, performing carbon dioxide back extraction to obtain a rubidium-cesium carbonate solution, and performing concentration and crystallization to obtain a rubidium-cesium mixed carbonate, wherein the composition of the obtained rubidium-cesium mixed carbonate is as follows:

component (A)	Rb	Cs	K	Na	Ca	Mg	Fe
								Content (%)	62.78	12.45	0.002	0.0006	0.0003	0.0001	0.0001

Adding the rubidium-cesium mixed carbonate and analytically pure aluminum hydroxide into a reaction kettle according to a certain proportion, adding water or mother liquor, stirring uniformly, gradually adding hydrofluoric acid, controlling a proper reaction temperature, obtaining rubidium-cesium fluoroaluminate crystals, and obtaining the rubidium-cesium fluoroaluminate products meeting the requirements through centrifugal separation, drying and crushing. The composition of the obtained rubidium-caesium fluoroaluminate product is as follows:

the reaction principle of the invention is as follows: under heating, the mixed vanadium of potassium, rubidium and cesium is converted into a sulfate solution of potassium, rubidium and cesium by lime, and the reaction formula is as follows:

2(K、Rb、Cs)Al(SO₄)₂·12H₂O+3CaO+H₂O→(K、Rb、Cs)₂SO₄+2Al(OH)₃+3CaSO₄

carrying out co-extraction by using a special extractant, separating rubidium and cesium from potassium and other impurities to obtain relatively pure rubidium and cesium mixed carbonate, wherein the reaction formula is as follows:

extraction (Rb, Cs)₂SO₄+4ROH→H⁺+(Rb、Cs)OR·(ROH)₃

Wherein ROH represents a special extractant.

Back extraction 2(Rb, Cs) OR (ROH)₃+CO₂+H₂O→(Rb、Cs)₂CO₃+4ROH

Synthesizing a rubidium and cesium fluoroaluminate aluminum brazing flux product in a reactor kettle with a stirrer, wherein the reaction formula is as follows:

(Rb、Cs)₂CO₃+Al(OH)₃+HF→(Rb、Cs)_mAlF_4+n

in the above reaction formula, m represents 1, 2 or 3, and n represents 0, 1 or 2.

A preparation method of rubidium and cesium fluoroaluminate aluminum soldering flux comprises the following steps:

(1) potassium, rubidium and cesium mixed alum conversion: reacting potassium, rubidium and cesium mixed alum with lime to convert the mixed alum into a sulfate solution of potassium, rubidium and cesium; determining the adding proportion of the potassium, rubidium and cesium mixed alum to lime to be 1: 0.4, the reaction temperature is 80 to 90 ℃, and the reaction time is 1 hour.

(2) Liquid-solid separation: carrying out filter pressing on the converted materials, washing residues with pure water, using the washing liquid for conversion reaction, and carrying out filter pressing to obtain a pure carbonate solution of potassium, rubidium and cesium;

(3) and (3) performing co-extraction of rubidium and cesium: co-extracting the sulfate solution of potassium, rubidium and cesium by using an extracting agent, and performing back extraction by using carbon dioxide to obtain a carbonate solution of rubidium and cesium; in the back extraction solution after the co-extraction, the removal rate of potassium is more than 99.9 percent;

(4) concentration and crystallization: concentrating and crystallizing the solution to obtain mixed carbonate solid of rubidium and cesium;

(5) synthesis of rubidium and cesium fluoroaluminates: adding rubidium and cesium mixed carbonate and analytically pure aluminum hydroxide into a reaction kettle according to a proper ratio, wherein the ratio of the rubidium and cesium mixed carbonate to the analytically pure aluminum hydroxide is 1: (0.50-0.60), adding pure water or mother liquor, and uniformly stirring;

(6) gradually adding hydrofluoric acid into a reaction kettle, controlling the end point pH value of hydrofluoric acid to be 6-8, controlling the adding amount of the hydrofluoric acid to be based on reaching the end point pH, controlling the acid adding time to be within 2 hours, continuing to react for 2-3 hours after the acid is added, controlling the reaction temperature to be 80-90 ℃, and continuing to stir until a qualified rubidium-cesium fluoroaluminate product is generated after the reaction reaches the end point; the material after the reaction is finished needs to be cooled to 40 ℃ to 45 ℃.

(7) Centrifugal separation: carrying out centrifugal separation on the materials to obtain a wet product; and (5) separating the obtained mother liquor, and returning the mother liquor to the step (5) for recycling for batching.

(8) Drying: drying the wet product by using an oven; the drying temperature is controlled to be 200-220 ℃, and the drying time is controlled to be constant temperature for 2-3 hours.

(9) Crushing: and (4) crushing the dried product by using an ultrafine crusher to obtain a powdery product with the required granularity, packaging, and warehousing after the product is qualified. Particle size D of the pulverized product₅₀The melting temperature of the product is controlled to be 465-485 ℃.

Example 1

(1) Adding a potassium, rubidium and cesium mixed alum raw material into a reaction kettle containing washing liquor, heating to 90 ℃, and then mixing the potassium, rubidium and cesium mixed alum with lime according to a ratio of 1: lime is added according to the proportion of 0.4, the reaction temperature is controlled at 85 ℃, and the reaction lasts for 1 hour.

(2) And (2) carrying out filter pressing on the material reacted in the step (1) by using a filter press, blowing the material for 5 minutes by using compressed air after the filter pressing is finished to obtain a sulfate solution containing potassium, rubidium and cesium, washing the slag in the filter press by using pure water, and feeding the washing solution into a washing solution tank.

(3) Performing rubidium-cesium co-extraction on the potassium-rubidium-cesium sulfate solution obtained in the step (2) by using an extracting agent, and performing back extraction by using carbon dioxide to obtain a rubidium-cesium mixed carbonate solution.

(4) And (4) concentrating and crystallizing the rubidium-cesium mixed carbonate solution obtained in the step (3), and then cooling and separating to obtain a rubidium-cesium mixed carbonate crystal.

(5) Mixing rubidium-cesium mixed carbonate crystals obtained in the step (4) with analytically pure aluminum hydroxide according to a ratio of 1: 196.25 kg of the mother liquor with the proportion of 0.57 is added into a reaction kettle with the volume of two cubic meters and containing 300 liters of the mother liquor, the mixture is stirred evenly and then heated to more than 50 ℃.

(6) Gradually adding 50% hydrofluoric acid into the reaction kettle in the step (5), controlling the adding speed to ensure that the reaction temperature in the kettle is less than 90 ℃, stopping adding the hydrofluoric acid until the pH value of the materials in the kettle is 6.5, and continuously stirring and reacting for 2.5 hours.

(7) And (5) cooling the materials in the reaction kettle to 40 ℃ in the step (6), performing centrifugal separation on the materials to obtain a wet rubidium and cesium fluoroaluminate product, and returning the mother liquor obtained by separation to the step (5) for recycling and batching.

(8) And (4) putting the wet product obtained in the step (7) into a baking oven, and drying at the constant temperature of 220 ℃ for 3 hours to obtain a dry product of rubidium and cesium fluoroaluminate.

(9) Adding the dry product of rubidium and cesium fluoroaluminates obtained in the step (8) into a grinder for grinding to obtain a particle size D₅₀Powder product of 10.2um, sampled for analysis, the analysis results are as follows:

example 2

(1) Adding a potassium, rubidium and cesium mixed alum raw material into a reaction kettle containing washing liquor, heating to 90 ℃, and then mixing the potassium, rubidium and cesium mixed alum with lime according to a ratio of 1: lime is added according to the proportion of 0.4, the reaction temperature is controlled at 85 ℃, and the reaction lasts for 1 hour.

(2) And (2) carrying out filter pressing on the material reacted in the step (1) by using a filter press, blowing the material for 5 minutes by using compressed air after the filter pressing is finished to obtain a sulfate solution containing potassium, rubidium and cesium, washing the slag in the filter press by using pure water, and feeding the washing solution into a washing solution tank.

(3) Performing rubidium-cesium co-extraction on the potassium-rubidium-cesium sulfate solution obtained in the step (2) by using a special extracting agent, and performing back extraction by using carbon dioxide to obtain a rubidium-cesium mixed carbonate solution.

(4) And (4) concentrating and crystallizing the rubidium-cesium mixed carbonate solution obtained in the step (3), and then cooling and separating to obtain a rubidium-cesium mixed carbonate crystal.

(5) Mixing rubidium-cesium mixed carbonate crystals obtained in the step (4) with analytically pure aluminum hydroxide according to a ratio of 1: 193.75 kg of the mother liquor with the proportion of 0.55 is added into a reaction kettle with the volume of two cubic meters and containing 300 liters of the mother liquor, the mixture is stirred evenly and then heated to more than 50 ℃.

(6) Gradually adding 50% hydrofluoric acid into the reaction kettle in the step (5), controlling the adding speed to ensure that the reaction temperature in the kettle is less than 90 ℃, stopping adding the hydrofluoric acid until the pH value of the materials in the kettle is 6.5, and continuously stirring and reacting for 3 hours.

(7) And (5) cooling the materials in the reaction kettle to 40 ℃ in the step (6), performing centrifugal separation on the materials to obtain a wet rubidium and cesium fluoroaluminate product, and returning the mother liquor obtained by separation to the step (5) for recycling and batching.

(8) And (4) putting the wet product obtained in the step (7) into a baking oven, and drying at the constant temperature of 220 ℃ for 3 hours to obtain a dry product of rubidium and cesium fluoroaluminate.

(9) Adding the dry product of rubidium and cesium fluoroaluminates obtained in the step (8) into a grinder for grinding to obtain a particle size D₅₀Powder product of 10.31um, sampled and analyzed, the analysis results are as follows:

example 3

(1) Adding a potassium, rubidium and cesium mixed alum raw material into a reaction kettle containing washing liquor, heating to 90 ℃, then adding lime, controlling the reaction temperature at 85-90 ℃, and reacting for 1 hour.

(2) And (2) carrying out filter pressing on the material reacted in the step (1) by using a filter press, blowing the material for 5 minutes by using compressed air after the filter pressing is finished to obtain a sulfate solution containing potassium, rubidium and cesium, washing the slag in the filter press by using pure water, and feeding the washing solution into a washing solution tank.

(3) Performing rubidium-cesium co-extraction on the potassium-rubidium-cesium sulfate solution obtained in the step (2) by using an extracting agent, and performing back extraction by using carbon dioxide to obtain a rubidium-cesium mixed carbonate solution.

(4) And (4) concentrating and crystallizing the rubidium-cesium mixed carbonate solution obtained in the step (3), and then cooling and separating to obtain a rubidium-cesium mixed carbonate crystal.

(5) Mixing rubidium-cesium mixed carbonate crystals obtained in the step (4) with analytically pure aluminum hydroxide according to a ratio of 1: 193.75 kg of the mother liquor with the proportion of 0.55 is added into a reaction kettle with the volume of two cubic meters and containing 300 liters of the mother liquor, the mixture is stirred evenly and then heated to more than 50 ℃.

(6) Gradually adding 50% hydrofluoric acid into the reaction kettle in the step (5), controlling the adding speed to ensure that the reaction temperature in the kettle is less than 90 ℃, stopping adding the hydrofluoric acid until the pH value of the materials in the kettle is 7, and continuously stirring and reacting for 3 hours.

(7) And (5) cooling the materials in the reaction kettle to 42 ℃ in the step (6), performing centrifugal separation on the materials to obtain a wet rubidium and cesium fluoroaluminate product, and returning the mother liquor obtained by separation to the step (5) for recycling and batching.

(8) And (4) putting the wet product obtained in the step (7) into a baking oven, and drying at the constant temperature of 220 ℃ for 3 hours to obtain a dry product of rubidium and cesium fluoroaluminate.

(9) Adding the dry product of rubidium and cesium fluoroaluminates obtained in the step (8) into a grinder for grinding to obtain a particle size D₅₀Powder product of 10.33um, sampled for analysis, the analysis results are as follows:

example 4

(1) Adding the potassium, rubidium and cesium mixed alum raw material into a reaction kettle containing washing liquor, heating to 90 ℃, then adding lime, controlling the reaction temperature to be 85-90 ℃, and reacting for 1 hour.

(2) And (2) carrying out filter pressing on the material reacted in the step (1) by using a filter press, blowing the material for 5 minutes by using compressed air after the filter pressing is finished to obtain a sulfate solution containing potassium, rubidium and cesium, washing the slag in the filter press by using pure water, and feeding the washing solution into a washing solution tank.

(3) Performing rubidium-cesium co-extraction on the potassium-rubidium-cesium sulfate solution obtained in the step (2) by using a special extracting agent, and performing back extraction by using carbon dioxide to obtain a rubidium-cesium mixed carbonate solution.

(4) And (4) concentrating and crystallizing the rubidium-cesium mixed carbonate solution obtained in the step (3), and then cooling and separating to obtain a rubidium-cesium mixed carbonate crystal.

(5) Mixing rubidium-cesium mixed carbonate crystals obtained in the step (4) with analytically pure aluminum hydroxide according to a ratio of 1: 191.25 kg of the mother liquor of 300 liters are added into a reaction kettle with the volume of two cubic meters and the mother liquor of 0.53, evenly stirred and heated to more than 50 ℃.

(6) Gradually adding 50% hydrofluoric acid into the reaction kettle in the step (5), controlling the adding speed to ensure that the reaction temperature in the kettle is less than 90 ℃, stopping adding the hydrofluoric acid until the pH value of the materials in the kettle is 7.5, and continuously stirring and reacting for 3 hours.

(7) And (5) cooling the materials in the reaction kettle to 40 ℃ in the step (6), performing centrifugal separation on the materials to obtain a wet rubidium and cesium fluoroaluminate product, and returning the mother liquor obtained by separation to the step (5) for recycling and batching.

(8) And (4) putting the wet product obtained in the step (7) into a baking oven, and drying at the constant temperature of 220 ℃ for 3 hours to obtain a dry product of rubidium and cesium fluoroaluminate.

(9) Adding the dry product of rubidium and cesium fluoroaluminates obtained in the step (8) into a grinder for grinding to obtain a particle size D₅₀Powder product of 10.54um, sampled and analyzed, the analysis result is as follows:

the effectiveness of the rubidium and cesium fluoroaluminate products obtained in the four embodiments on trial use of aluminum brazing is as follows:

example numbering	Example 1	Example 2	Example 3	Example 4
					Trial effect	Good effect	Good taste	Good taste	Good effect