WO2017080245A1

WO2017080245A1 - Method for preparing high-purity strontium hydroxide by using strontium slag

Info

Publication number: WO2017080245A1
Application number: PCT/CN2016/089851
Authority: WO
Inventors: 金建华; 俞青芬; 李磊; 刘明地; 姜小萍
Original assignee: 严利容
Priority date: 2015-11-10
Filing date: 2016-07-13
Publication date: 2017-05-18
Also published as: CN105293554A; CN105293554B

Abstract

A method for preparing high-purity strontium hydroxide by using strontium slag. The method comprises the steps of: (1) grinding the strontium slag; (2) dissolving the ground strontium slag into water and adding a mixed solution of sulfuric acid and hydrochloric acid, and performing filtering to obtain a liquid-state first solution; (3) adding a sodium hydroxide solution into the first solution, performing filtering and separation of the sediment after the heating, so as to obtain a liquid-state second solution; (4) adding the sodium hydroxide solution into the second solution, performing heating to 40ºC to 70ºC and then maintaining a constant temperature for 0.5-2 h, performing filtering and separation of the sediment, so as to obtain the strontium chloride solution; (5) adding deionized water into the strontium chloride solution to dilute the strontium chloride solution and then adding sodium hydroxide solution to perform alkali decomposition, and filtering the precipitated crystals to obtain coarse strontium hydroxide crystals; and (6) recrystalizing the coarse strontium hydroxide crystals, so as to obtain high-purity strontium hydroxide crystals. In the method, tailing resources are utilized, the strontium ore utilization rate is improved, and the environmental pollution caused by tailings is reduced.

Description

Method for preparing high-purity barium hydroxide by using slag

Technical field

The invention belongs to the technical field of chemical industry, and in particular relates to a method for preparing high-purity barium hydroxide by using slag.

Background technique

Barium carbonate is an important chemical raw material. It is widely used in color picture tube glass bulbs, cathode ray tubes, electronic ceramics, and magnetic materials because of its strong absorption of X-ray and γ-ray functions and other unique physical and chemical properties. The manufacture of industrial materials such as materials, fuels, paints, etc. involves electronics, chemicals, military, building materials, non-ferrous metals, aerospace, light industry, medicine, food and many other industries. With the rapid development of electronic components, magnetic materials and ceramic materials at home and abroad, the quality of strontium carbonate products is also higher. In the past, research on strontium carbonate has focused on how to make production efficient, high purity and so on. .

The proven celestite deposit in the Dafengshan area of the Qaidam Basin in Qinghai has a reserve of more than 20 million tons of barium sulfate, making it the largest antimony deposit in the world. In the prior art, industrial grade barium carbonate is mainly prepared by a process of high temperature calcination-carbon reduction-water leaching of celestite, and 2.5 tons of waste slag (tailing) is produced for each ton of industrial grade barium carbonate produced. If these waste residues are not used, it will cause waste of resources and cause pollution to the environment. Therefore, it is of great significance to study the process of preparing barium hydroxide by using barium residue.

Summary of the invention

In view of the above, the present invention provides a method for preparing high-purity barium hydroxide by using slag, which is mainly prepared by using waste slag produced by using celestite by reduction method to prepare industrial grade lanthanum carbonate, by removing impurities therein. The high purity barium hydroxide is obtained, and the purity of barium hydroxide is above the analytical grade level.

In order to achieve the above object, the present invention adopts the following technical solutions:

A method for preparing high-purity barium hydroxide by using slag, comprising the steps of: (1) grinding a slag; wherein the cerium in the slag has a weight percentage of 20% to 26%, and the cerium exists in a form comprising carbonic acid One or more of cerium, barium sulfate, barium hydroxide, barium silicate and barium aluminate; the impurities in the barium mainly include one or more of calcium, barium, magnesium, aluminum and silicon a carbonate or an oxide; (2) dissolving the ground slag after being ground in water to form a slurry, and adding a mixed solution of sulfuric acid and hydrochloric acid to the slurry to adjust the dissolution The pH of the liquid is 0-0.2, and then heated to 80-100 ° C, and the temperature is 0.5-2 h, and the precipitate is separated by filtration to obtain a first solution in a liquid state; (3) a sodium hydroxide solution is added to the first solution. Adjusting the pH of the first solution to 7 to 9.5, then heating to 50 to 75 ° C and then maintaining the temperature for 0.5 to 2 hours, and then separating the precipitate by filtration to obtain a second liquid solution; (4) to the second Adding a sodium hydroxide solution to the solution, adjusting the pH of the second solution to 10-12, and then heating to 40-70 ° C, then maintaining the temperature for 0.5-2 h, and then separating the precipitate by filtration, and the obtained solution is a ruthenium chloride solution; (5), diluting the cerium chloride solution with deionized water, adding a sodium hydroxide solution for alkali precipitation, filtering the precipitated crystals to obtain a crude cerium hydroxide crystal; (6), the crude The cerium hydroxide crystals are recrystallized to obtain high purity cerium hydroxide crystals.

Further, in the step (2), the slurry is mixed with water at a mass ratio of 1:1 to 3 to form the slurry.

Further, in the step (2), the mixed solution of sulfuric acid and hydrochloric acid is added, the concentration of sulfuric acid is 0.5% to 1%, and the concentration of hydrochloric acid is 15% to 20%.

Further, in the step (2), the solution is heated to 85 to 90 ° C, and then the temperature is kept for 1 to 1.5 hours.

Further, in the steps (3) and (4), the solution is heated to 50 to 60 ° C, and then thermostated for 1 to 1.5 hours.

Further, in the steps (3) and (4), the sodium hydroxide solution is added in a mass percentage of 15% to 20%.

Further, in the step (5), the mass percentage concentration of the sodium hydroxide solution added is 20% to 30%.

Further, the step (6) specifically comprises: first dissolving the crude barium hydroxide crystals with deionized water, the deionized water added is 3 to 3.5 times the weight of the crude barium hydroxide crystal; and then heating After boiling for 25 to 30 minutes, it was filtered, and finally the filtrate was cooled to obtain high-purity barium hydroxide crystals.

Further, the filtrate was placed in ice water and cooled in a water bath.

Further, the slag is a slag produced by preparing industrial grade lanthanum carbonate by a process of high temperature calcination-carbon reduction-water leaching of lapis lazuli.

The method for preparing high-purity barium hydroxide by using the slag residue provided by the embodiment of the invention uses the slag residue as a raw material to prepare cerium hydroxide having a purity higher than the analytical grade. The method utilizes tailings resources, improves the utilization rate of the antimony ore, and reduces the environmental pollution of the tailings; the method has the advantages of short process, simple equipment and low cost, and is suitable for large-scale industrial production.

DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a process flow diagram of a method for preparing high-purity barium hydroxide using bismuth slag provided by the present invention.

2 is an XRD chart of barium hydroxide prepared in Example 1 of the present invention.

Fig. 3 is an XRD chart of barium hydroxide prepared in Example 2 of the present invention.

4 is an XRD chart of barium hydroxide prepared in Example 3 of the present invention.

detailed description

The invention will now be further described by way of examples with reference to the accompanying drawings.

Referring to FIG. 1, the method for preparing high-purity barium hydroxide using the slag residue provided by the present invention comprises the steps of:

S101, grinding slag. Wherein, the slag is a slag produced by preparing industrial grade lanthanum carbonate by a process of high temperature calcination-carbon reduction-water leaching of lapis lazuli. Specifically, the weight percentage of cerium in the slag is 20% to 26%, and the present form of cerium includes one or more of cerium carbonate, barium sulfate, barium hydroxide, barium silicate and barium aluminate. The impurities in the slag mainly include carbonates or oxides of one or more of calcium, barium, magnesium, aluminum and silicon, and some compounds of iron, lead and nickel.

S102. Dissolving the ground slag after grinding into water to form a slurry, adding a mixed solution of sulfuric acid and hydrochloric acid to the slurry, and separating the precipitate by filtration to obtain a liquid first solution. Specifically, first, the slag and water are mixed at a mass ratio of 1:1 to 3 to form a slurry, and a mixed solution of sulfuric acid and hydrochloric acid is added to the slurry to adjust the pH of the solution to 0 to 0.2. Then, the mixed solution is heated to 80 to 100 ° C (this temperature is more suitably 85 to 90 ° C) and then the temperature is 0.5 to 2 h (this time is more suitably 1.5 to 2 h); finally, cooling, filtering, separating the precipitate , a liquid first solution is obtained. In this step, mainly separating and removing insoluble impurities and converting Ba ²⁺ into barium sulfate precipitation removal; wherein, in the mixed solution of sulfuric acid and hydrochloric acid added, the concentration of sulfuric acid is 0.5% to 1%, hydrochloric acid The mass concentration is 15% to 20%. The mixed acid solution should be such that the amount of sulfuric acid can completely remove Ba ²⁺ , preferably in excess. The amount of sulfuric acid selected here is 105% to 110% of the theoretical calculation. .

S103, adding a sodium hydroxide solution to the first solution, adjusting the pH of the first solution to 7 to 9.5, and separating the precipitate by filtration to obtain a liquid second solution. Specifically, firstly adding a sodium hydroxide solution having a mass percentage of 15% to 20%, stirring well, and adjusting the pH of the mixed solution to a range of 7 to 9.5, and then heating the mixed solution to 50 to 75 ° C. After that (this temperature is more suitable is 70-75 ° C), the temperature is 0.5 to 2 h (this time is more suitable is 1 to 1.5 h); the precipitate is separated by filtration to obtain a cerium chloride solution. In this step, impurities of elements such as Al ³⁺ , Fe ³⁺ , and Pb ²⁺ are mainly separated.

S104, adding a sodium hydroxide solution to the second solution, adjusting the pH of the second solution to 10-12, and separating the precipitate by filtration, and the obtained solution is a barium chloride solution. Specifically, firstly adding a sodium hydroxide solution having a mass percentage of 15% to 20%, stirring well, and adjusting the pH of the mixed solution to a range of 10 to 12; then heating the mixed solution to 40 to 70 ° C (This temperature is more suitable is 65 ~ 70 ° C) and the temperature is 0.5 ~ 2h (this time is more suitable is 1 ~ 1.5h); finally, the precipitate is separated by filtration to obtain a cerium chloride solution. In this step, the Ca ²⁺ , Mg ²⁺ and Ni ²⁺ plasmas are mainly converted into hydroxide precipitates for removal.

S105, diluting the cerium chloride solution with deionized water, adding a sodium hydroxide solution for alkali precipitation, and filtering the precipitated crystal to obtain a crude cerium hydroxide crystal. Specifically, the concentration of the sodium hydroxide solution added is 20% to 30%, and the amount added is 105% to 110% of the theoretical calculation amount.

S106, recrystallizing the crude barium hydroxide crystals to obtain high-purity barium hydroxide crystals. Specifically, the crude barium hydroxide crystals are first dissolved in deionized water, and the deionized water added is 3 to 3.5 times the weight of the crude barium hydroxide crystals; then heated to boiling and held for 25 to 30 minutes. After filtration, the filtrate was finally cooled to obtain high purity cesium hydroxide crystals.

As a preferred solution, in step S106, the filtrate is placed in an ice water bath to cool, and the yield of the product can be increased by about 15%.

According to the above method, cerium hydroxide having a purity of at least the analytical grade level can be prepared by using slag as a raw material. The method utilizes tailings resources, improves the utilization rate of the antimony ore, and reduces the environmental pollution of the tailings.

Example 1

First, the slag is ground. The smaller the particle size, the better.

2. Mixing the ground slag and water in a ratio of 1:1 by mass to form a slurry, adding a mixed solution of sulfuric acid and hydrochloric acid to the slurry, wherein the mass percentage of sulfuric acid is 0.5% to 1%, and hydrochloric acid The mass percentage concentration is 15% to 20%, the pH of the control solution is 0 to 0.2, and the temperature is adjusted to 1 hour after heating to 85 ° C, and then the precipitate is separated by filtration to obtain a liquid first solution.

3. Adding a 15% sodium hydroxide solution to the first solution, adjusting the pH of the first solution to 7, heating to 70 ° C, and then thermostating for 1 h, and then separating the precipitate by filtration to obtain a liquid second solution.

4. Adding a sodium hydroxide solution having a mass concentration of 15% to the second solution, adjusting the pH of the second solution to 10, heating to 60 ° C, thermostating for 1 h, and then separating the precipitate by filtration to obtain a solution. It is a barium chloride solution.

5. After diluting the cerium chloride solution with deionized water, adding sodium hydroxide solution for alkali precipitation, the concentration of the added sodium hydroxide solution is 30%, and the amount added is 105% to 110% of the theoretical calculation amount. The precipitated crystals were filtered to obtain crude barium hydroxide crystals.

6. The crude barium hydroxide crystals are recrystallized to obtain high purity barium hydroxide crystals. Specifically, the crude barium hydroxide crystals are first dissolved in deionized water, and the deionized water added is three times the weight of the crude barium hydroxide crystals; then heated to boiling and held for 25 minutes, filtered, and finally The filtrate was naturally cooled to obtain high purity barium hydroxide crystals.

The crystal obtained in the sixth step is subjected to XRD diffraction analysis to obtain the XRD pattern of FIG. 2, as shown in FIG. 2, the crystal diffraction peak prepared by the present example and the standard map of cesium hydroxide (JCPDS card no. 00-027-1438) ) Consistent, no peaks appear, belonging to the tetragonal system. After the detection, the obtained barium hydroxide crystal is barium hydroxide octahydrate (Sr(OH) ₂ ·8H ₂ O), and its purity is above the analytical grade.

Example 2

First, the slag is ground. The smaller the particle size, the better.

2. The ground slag and water are mixed according to a mass ratio of 1:2 to form a slurry, and a mixed solution of sulfuric acid and hydrochloric acid is added to the slurry, wherein the mass percentage of sulfuric acid is 0.5% to 1%, and hydrochloric acid is used. The mass percentage concentration is 15% to 20%, the pH of the control solution is 0 to 0.2, and after heating to 90 ° C, the temperature is kept for 2 hours, and then the precipitate is separated by filtration to obtain a liquid first solution.

3. Adding 18% sodium hydroxide solution to the first solution, adjusting the pH of the first solution to 8, heating to 50 ° C and then thermostating for 2 h, and then separating the precipitate by filtration to obtain a liquid second solution.

4. Adding a sodium hydroxide solution having a mass concentration of 18% to the second solution, adjusting the pH of the second solution to 11, heating to 50 ° C, and then thermostating for 2 h, and then separating the precipitate by filtration to obtain a solution. It is a barium chloride solution.

5. After diluting the cerium chloride solution with deionized water, adding sodium hydroxide solution for alkali precipitation, the concentration of the added sodium hydroxide solution is 20%, and the amount added is 105% to 110% of the theoretical calculation amount. The precipitated crystals were filtered to obtain crude barium hydroxide crystals.

6. The crude barium hydroxide crystals are recrystallized to obtain high purity barium hydroxide crystals. Specifically, the crude barium hydroxide crystals are first dissolved in deionized water, and the deionized water added is 3.5 times the weight of the crude barium hydroxide crystals; then heated to boiling and kept for 30 minutes, filtered, and finally The filtrate was placed in ice water and cooled to about 5 ° C in a water bath to obtain high-purity barium hydroxide crystals. This embodiment adopts Cooling with an ice water water bath increased the yield of the product by about 15% compared to the natural cooling used in Example 1.

The crystal obtained in the sixth step is subjected to XRD diffraction analysis to obtain an XRD pattern of FIG. 3, as shown in FIG. 3, the crystal diffraction peak prepared by the present example and the standard map of barium hydroxide (JCPDS card no. 00-027-1438) ) Consistent, no peaks appear, belonging to the tetragonal system. After the detection, the obtained barium hydroxide crystal is barium hydroxide octahydrate (Sr(OH) ₂ ·8H ₂ O), and its purity is above the analytical grade.

Example 3

First, grinding the slag. The smaller the particle size, the better.

2. Mixing the ground slag and water in a ratio of 1:3 to form a slurry, adding a mixed solution of sulfuric acid and hydrochloric acid to the slurry, wherein the mass percentage of sulfuric acid is 0.5% to 1%, and the quality of hydrochloric acid The percentage concentration is 15% to 20%, the pH of the control solution is 0 to 0.2, and then the mixed solution is heated to 100 ° C and then kept at a constant temperature for 1.5 h; finally, the precipitate is cooled, filtered, and a liquid first solution is obtained.

3. Adding 20% sodium hydroxide solution to the first solution, adjusting the pH of the first solution to 9.5, heating to 60 ° C, and maintaining the temperature for 0.5 h, and then separating the precipitate by filtration to obtain a liquid second solution.

4. Adding a 20% by mass sodium hydroxide solution to the second solution, fully stirring and adjusting the pH of the mixed solution to 12; then heating the mixed solution to 70 ° C for 2 h; finally filtering and separating the precipitate to obtain Barium chloride solution.

5. Dilute the cerium chloride solution with deionized water, and then add sodium hydroxide solution for alkali precipitation. The concentration of the added sodium hydroxide solution is 25%, and the amount added is 105% to 110 of the theoretical calculation amount. %, the precipitated crystals were filtered to obtain crude barium hydroxide crystals.

6. The crude barium hydroxide crystals are recrystallized to obtain high purity barium hydroxide crystals. Specifically, the crude barium hydroxide crystals are first dissolved in deionized water, and the deionized water added is 3.2 times the weight of the crude barium hydroxide crystals; then heated to boiling and kept for 30 minutes, filtered, and finally The filtrate was placed in ice water and cooled to 10 ° C or lower to obtain high-purity barium hydroxide crystals. This embodiment uses an ice water water bath to cool, and the product yield can be increased by about 15% compared to the natural cooling in Example 1.

The crystal obtained in the step 5 was subjected to XRD diffraction analysis to obtain an XRD pattern of FIG. 4, as shown in FIG. 4, the crystal diffraction peak prepared by the present example and the standard map of barium hydroxide (JCPDS card no. 00-027-1438) Consistent, no peaks appear, belonging to the orthorhombic system. After the detection, the obtained barium hydroxide crystal is barium hydroxide octahydrate (Sr(OH) ₂ ·8H ₂ O), and its purity is above the analytical grade.

In summary, the method for preparing high-purity barium hydroxide by using the slag residue provided by the embodiment of the invention is prepared by using slag as raw material to obtain cerium hydroxide having a purity higher than the analytical grade. The method utilizes tailings resources, improves the utilization rate of the antimony ore, and reduces the environmental pollution of the tailings; the method has the advantages of short process, simple equipment and low cost, and is suitable for large-scale industrial production.

The above description is only a specific embodiment of the present application, and it should be noted that those skilled in the art can also make several improvements and retouchings without departing from the principles of the present application. It should be considered as the scope of protection of this application.

Claims

A method for preparing high-purity barium hydroxide by using slag, wherein the method comprises the steps of:

(1) grinding the slag; wherein, the cerium slag has a weight percentage of 20% to 26%, and the cerium exists in the form of cerium carbonate, barium sulfate, barium hydroxide, barium silicate and aluminate. One or more of the crucibles; the impurities in the antimony slag mainly include carbonates or oxides of one or more elements of calcium, barium, magnesium, aluminum and silicon;

(2) dissolving the ground slag after being ground in water to form a slurry, adding a mixed solution of sulfuric acid and hydrochloric acid to the slurry, adjusting the pH of the solution to 0 to 0.2, and then heating to 80 to 100 ° C and then maintaining a constant temperature of 0.5. ~ 2h, the precipitate is separated by filtration to obtain a liquid first solution;

(3) adding a sodium hydroxide solution to the first solution, adjusting the pH of the first solution to 7 to 9.5, then heating to 50 to 75 ° C, and then maintaining the temperature for 0.5 to 2 hours, and then separating and separating the precipitate by filtration. Obtaining a second liquid solution;

(4) adding a sodium hydroxide solution to the second solution, adjusting the pH of the second solution to 10 to 12, then heating to 40 to 70 ° C, and then maintaining the temperature for 0.5 to 2 hours, and then separating and separating the precipitate by filtration. The resulting solution is a barium chloride solution;

(5), diluting the cerium chloride solution with deionized water, adding a sodium hydroxide solution for alkali precipitation, and filtering the precipitated crystals to obtain a crude cerium hydroxide crystal;

(6) The crude barium hydroxide crystals are recrystallized to obtain high-purity barium hydroxide crystals.
The method for producing high-purity barium hydroxide by using slag according to claim 1, wherein in the step (2), the slag is mixed with water at a mass ratio of 1:1 to 3 to form the slurry.
The method for preparing high-purity barium hydroxide by using slag according to claim 1, wherein in the mixed solution of sulfuric acid and hydrochloric acid added in step (2), the mass concentration of sulfuric acid is 0.5% to 1%, and the mass of hydrochloric acid The percentage concentration is 15% to 20%.
The method for preparing high-purity barium hydroxide by using slag according to claim 1, wherein in the step (2), the solution is heated to 85 to 90 ° C, and then the temperature is kept for 1 to 1.5 hours.
The method for preparing high-purity barium hydroxide by using slag according to claim 1, wherein in the steps (3) and (4), the solution is heated to 50 to 60 ° C, and then thermostated for 1 to 1.5 hours.
The method for preparing high-purity barium hydroxide by using slag according to claim 1, wherein the step In (3) and (4), the mass percentage concentration of the sodium hydroxide solution to be added is 15% to 20%.
The method for preparing high-purity barium hydroxide by using slag according to claim 1, wherein in the step (5), the sodium hydroxide solution is added in a mass percentage of 20% to 30%.
The method for preparing high-purity barium hydroxide by using slag according to claim 1, wherein the step (6) specifically comprises: first dissolving the crude barium hydroxide crystals with deionized water, and the added deionized water is coarse. The weight of the prepared barium hydroxide crystals is 3 to 3.5 times; then, it is heated to boiling and kept for 25 to 30 minutes, and then filtered, and finally the filtrate is cooled to obtain high-purity barium hydroxide crystals.
The method for producing high-purity barium hydroxide by using slag according to claim 8, wherein the filtrate is placed in ice water and cooled in a water bath.
The method for preparing high-purity barium hydroxide by using slag according to claim 1, wherein the slag is a slag produced by preparing industrial grade lanthanum carbonate by a process of high temperature calcination-carbon reduction-water leaching of lapis lazuli.