A method for removing calcium and producing cerium fluoride from fluorite-containing bastnaesite

Abstract

The application discloses a method for removing calcium and producing cerium fluoride from fluorite-containing fluorocarbon cerite, which comprises the following steps: (1) grinding and sampling fluorite-containing fluorocarbon cerite after flotation, and sieving to obtain a mineral powder; (2) dissolving cerium dioxide to obtain a high-cerium nitrate solution; (3) using the high-cerium nitrate solution as a bottom water, slurry is prepared by using the mineral powder, nitric acid solution is added for stirring and reaction, flocculation and clarification are carried out, and then undissolved and floated minerals and a clear and transparent solution are obtained; the undissolved and floated minerals are filtered, washed and dried for later use; (4) the clear and transparent solution is added into ammonia water to precipitate a crude cerium fluoride product, the pH of the solution is adjusted to 1.0, stirring and reaction are carried out, the crude cerium fluoride product is washed and then calcined to obtain a cerium fluoride product. The method uses the high-cerium nitrate solution and the nitric acid solution to dissolve and float the minerals, and then the floated minerals without fluorite and the cerium fluoride product are obtained; and no reagent such as sodium hydroxide is used, so that the processing difficulty and cost of each section are reduced, and the utilization rate of fluorine sources is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the fluorine carbon cerium mineralization selection calcium removal technical field, specifically relates to a kind of from fluorite fluorine carbon cerium mineral in the production of cerium fluoride and production of calcium removal in fluorite fluorine carbon cerium mineral. BACKGROUND

[0002] Sichuan Mianling rare earth deposit is mainly fluorine carbon cerium mineral, and its inclusions size is fine, and the inclusions relationship with other minerals is complex.Fluorite, barite, gangue, strontium barium sulfate mineral and other associated minerals have high content, and the ore is seriously mudified, which causes the long mineral processing process.For the distribution of the mineral and the properties of multiple associated ores, the single or combined beneficiation process of flotation, magnetic separation and gravity separation is used to improve the rare earth grade of fluorine carbon cerium concentrate, and the removal rate of non-rare earth impurities such as desliming, fluorite, barite and iron ore is investigated.The fluorite in the fluorine carbon cerium ore is difficult to remove by beneficiation method because of its fine inclusions size and similar specific gravity with rare earth.

[0003] After the above series of beneficiation processes of Sichuan fluorine carbon cerium ore, part of the fluorite-containing flotation ore is obtained, and the rare earth grade of the flotation ore is 55%-62% and the fluorite content is 8%-14% after analysis and detection.The conventional process method for treating the flotation ore is: oxidation roasting-(hydrochloric acid+ sodium hydroxide) mixed leaching method, and fluorite is also dissolved in the solution by hydrochloric acid without special process treatment of fluorite.Because the main component of fluorite is calcium fluoride, the use of conventional oxidation roasting-(hydrochloric acid+ sodium hydroxide) mixed leaching method to treat the flotation ore greatly increases the processing difficulty of each section, including the consumption of sodium hydroxide, scaling, daily processing capacity and the product quality of lanthanum oxide will be affected to different degrees.Calcium element in fluorite is dissolved in the solution by hydrochloric acid, and is separated together with rare earth elements, and because calcium element is a difficult extraction component compared with rare earth elements, calcium is enriched in lanthanum solution.The use of ammonium carbonate or sodium carbonate to precipitate lanthanum reduces the efficiency of precipitation, and the impurity calcium in lanthanum oxide product is greatly increased, which seriously affects the product quality.In addition, the fluorine element in fluorite greatly increases the consumption of sodium hydroxide and industrial water in the wet metallurgy process.

[0004] The fluorite content in the mixed rare earth ore of Baotou Baiyunebo fluorine carbon cerium and monazite is also about 12%, and the method for treating fluorite in this ore type is to use hydrochloric acid to remove calcium under the condition of long time and high acidity, which does not effectively recover and utilize fluorine, causing waste of fluorine resources.For the fluorine carbon cerium flotation ore with high fluorite content, the present application provides a method for removing calcium from fluorite-containing fluorine carbon cerium mineral and producing cerium fluoride by using high cerium nitrate. SUMMARY

[0005] In order to solve the above technical problems, the purpose of the present application is to provide a method for removing calcium and producing cerium fluoride from fluorite-containing fluorocarbon cerium ore, which utilizes high cerium nitrate solution and nitric acid solution to dissolve and float the ore, obtains the target cerium fluoride product without fluorite, does not use reagents such as sodium hydroxide, reduces the processing difficulty and cost of each section, and improves the utilization rate of fluorine resources.

[0006] The technical scheme for solving the above technical problems is as follows: a method for removing calcium and producing cerium fluoride from fluorite-containing fluorocarbon cerium ore is provided, which comprises the following steps:

[0007] (1) The fluorite-containing fluorocarbon cerium ore is floated and ground for sampling, and then sieved through a 400-mesh screen to obtain ore powder;

[0008] (2) The cerium dioxide is dissolved with 65-68wt% nitric acid solution to obtain high cerium nitrate solution;

[0009] (3) The ore powder obtained in step (1) is used for slurry preparation with the high cerium nitrate solution obtained in step (2) as the bottom water, and then 65-68wt% nitric acid solution is added for stirring and reaction at 85-90°C for 5-6h, so that the residual acidity is 1.2-1.5mol / L, and flocculation and clarification are performed to obtain unsolved and floated ore and clear and transparent solution, and the unsolved and floated ore is filtered, washed and dried for later use;

[0010] (4) The clear and transparent solution obtained in step (3) is added with ammonia water under stirring at 55-60°C, and cerium fluoride crude product is precipitated in the solution, the solution pH is finally adjusted to 1.0, and stirring and reaction are continued for 10-20min, then the cerium fluoride crude product is washed and calcined at 500°C for 1h to obtain cerium fluoride product.

[0011] Further, in step (1), the fluorocarbon cerium ore containing fluorite has a rare earth content of 55-62wt% and a fluorite content of 8-14wt%.

[0012] Further, in step (2), the mass-volume ratio of cerium oxide to nitric acid solution is 80-100g:160-200mL.

[0013] Further, in step (3), the mass-volume ratio of ore powder to nitric acid solution is 400g:100-120mL.

[0014] Further, in step (3), 0.1-0.3wt% polyacrylamide solution is added for flocculation and clarification.

[0015] Further, in step (3), 67wt% nitric acid solution is added for stirring and reaction at 88°C for 5.5h.

[0016] Further, in step (4), the concentration of ammonia water is 10-30vt%.

[0017] The present application has the following advantages:

[0018] 1. The present application uses cerium nitrate to remove calcium and fluorine in fluorite carbonatite, and the fluorite component is treated first and does not enter the subsequent oxidation roasting and wet metallurgy process, so that the sodium hydroxide and industrial water are greatly reduced, the precipitation efficiency of lanthanum liquid after extraction separation is significantly improved, and the non-rare earth impurity calcium in lanthanum oxide product is significantly reduced.

[0019] 2. The present application uses low-value cerium oxide to obtain high-value cerium fluoride product, and efficiently recovers fluorine resources in fluorite; the tetravalent cerium forms a complex ion with fluorine ions at high acidity, and the complex ion is hydrolyzed and precipitated to form cerium fluoride as the acidity decreases; and the calcium element in fluorite exists in the solution in the form of calcium nitrate. DETAILED DESCRIPTION

[0020] The principles and characteristics of the present application are described below, and the examples are only used to explain the present application and are not used to limit the scope of the present application. If the specific conditions are not specified in the examples, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased on the market.

[0021] Example 1

[0022] A method for removing calcium and producing cerium fluoride from fluorite carbonatite containing fluorite, comprising the following steps:

[0023] (1) The fluorite carbonatite containing fluorite is floated and ground for sample preparation, and the ore powder is obtained by passing through a 400-mesh screen. The rare earth grade of the fluorite carbonatite containing fluorite is 58wt%, and the fluorite content is 14wt%;

[0024] (2) 100g of cerium dioxide is added to 200mL of clean water, and then 200mL of 68wt% nitric acid solution is slowly added to dissolve, to obtain a cerium nitrate solution;

[0025] (3) The cerium nitrate solution obtained in step (2) is used as the bottom water, and 400g of the ore powder obtained in step (1) is used for slurry preparation, and then 110mL of 68wt% nitric acid solution is added to react at 90℃ for 6h, so that the residual acidity is 1.3mol / L, and the flotation minerals that are not dissolved are flocculated and clarified, 320g of which is obtained, the fluorite calcium fluoride content is 0.6%, and it enters the subsequent oxidation roasting process, and the clear transparent solution is used;

[0026] (4) The clear and transparent solution obtained in step (3) is slowly added to ammonia water under stirring at 55°C, and cerium fluoride crude product is precipitated from the solution. The solution pH is finally adjusted to 1.0, and the stirring reaction is continued for 20 min. The cerium fluoride crude product is washed and calcined at 500°C for 1 h to obtain 116 g of cerium fluoride product.

[0027] Example 2

[0028] A method for removing calcium and producing cerium fluoride from fluorite-containing bastnaesite, comprising the following steps:

[0029] (1) The fluorite-containing bastnaesite is ground and sampled after flotation, and the obtained ore powder is passed through a 400-mesh screen. The fluorite-containing bastnaesite has a rare earth content of 62 wt% and a fluorite content of 12 wt%;

[0030] (2) 90 g of cerium dioxide is added to 200 mL of water, and then 180 mL of 67 wt% nitric acid solution is slowly added to dissolve and obtain a high cerium nitrate solution;

[0031] (3) The high cerium nitrate solution obtained in step (2) is used as the base water, and 400 g of the ore powder obtained in step (1) is used for slurry adjustment. Then, 110 mL of 67 wt% nitric acid solution is added for stirring reaction at 88°C for 5.5 h, so that the residual acidity is 1.5 mol / L. The solution is flocculated and clarified to obtain 337 g of unsolved flotation minerals, and the fluorite calcium fluoride content is 0.4%. The clear and transparent solution is used for subsequent oxidation roasting process.

[0032] (4) The clear and transparent solution obtained in step (3) is slowly added to ammonia water under stirring at 60°C, and cerium fluoride crude product is precipitated from the solution. The solution pH is finally adjusted to 1.0, and the stirring reaction is continued for 15 min. The cerium fluoride crude product is washed and calcined at 500°C for 1 h to obtain 110 g of cerium fluoride product.

[0033] Example 3

[0034] A method for removing calcium and producing cerium fluoride from fluorite-containing bastnaesite, comprising the following steps:

[0035] (1) The fluorite-containing bastnaesite is ground and sampled after flotation, and the obtained ore powder is passed through a 400-mesh screen. The fluorite-containing bastnaesite has a rare earth content of 62 wt% and a fluorite content of 9.4 wt%;

[0036] (2) 80 g of cerium dioxide is added to 200 mL of water, and then 200 mL of 65 wt% nitric acid solution is slowly added to dissolve and obtain a high cerium nitrate solution;

[0037] (3) using the cerium nitrate solution obtained in step (2) as a base water, 400 g of the ore powder obtained in step (1) is used for slurry preparation, then 110 mL of 65 wt% nitric acid solution is added, and the reaction is stirred at 88°C for 5 h, so that the residual acidity is 1.53 mol / L, flocculation and clarification are performed, 348 g of un-dissolved and un-flushed minerals are obtained, the fluorite and calcium fluoride content is 0.3%, and the subsequent oxidation roasting process is entered, and the clear and transparent solution is used for later use;

[0038] (4) the clear and transparent solution obtained in step (3) is slowly added to ammonia water under the condition of stirring at 60°C, the cerium fluoride crude product is precipitated in the solution, the solution pH is finally adjusted to 1.0, the stirring reaction is continuously performed for 20 min, and then the cerium fluoride crude product is washed and calcined at 500°C for 1 h, so that 110 g of the cerium fluoride product is obtained.

[0039] The element content in the cerium fluoride products obtained in examples 1-3 is detected, and the results are shown in Table 1.

[0040] Table 1: Chemical composition of cerium fluoride and Ca dissolution rate (unit: %)

[0041]

[0042] As shown in Table 1, the cerium nitrate and nitric acid solution are used for calcium removal from the high fluorite flotation ore, the calcium washing rate is more than 96%, and the produced cerium fluoride product meets the standard; the low fluorite flotation ore is subjected to oxidation roasting, and the calcium content in the mixed rare earth solution obtained by hydrochloric acid + sodium hydroxide wet dissolution is significantly reduced. And this method can remove the non-rare earth impurity calcium in advance, and recycle the fluorine resource, so that the cost and difficulty of the subsequent production process are reduced.

[0043] The above only describes the preferred embodiments of the present application, and is not used to limit the present application, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for the production of cerium fluoride by flotation from fluorite-containing bastnaesite, with calcium removal, characterized in that, The method comprises the following steps: (1) grinding and sampling fluorcarbonate cerium ore containing fluorite, passing through a 400-mesh screen to obtain ore powder, the fluorcarbonate cerium ore containing fluorite having a rare earth grade of 55-62 wt% and a fluorite content of 8-14 wt%; (2) dissolving cerium dioxide with a 65-68 wt% nitric acid solution to obtain a high cerium nitrate solution, the mass-volume ratio of the cerium dioxide and the nitric acid solution being 80-100 g: 160-200 mL; (3) using the high cerium nitrate solution obtained in step (2) as a bottom water, slurry is prepared with the ore powder obtained in step (1), then 65-68 wt% nitric acid solution is added, and stirring reaction is carried out at a temperature of 85-90 °C for 5-6 h, so that the residual acidity of the reaction is 1.2-1.5 mol / L, flocculation and clarification are carried out, and undissolved flotation minerals and clear transparent solution are obtained, the undissolved flotation minerals are filtered, washed and dried, and are ready for use; (4) under the condition of stirring at 55-60 °C, ammonia water is added to the clear transparent solution obtained in step (3), and cerium fluoride crude product is precipitated from the solution, the solution pH is finally adjusted to 1.0, stirring reaction is continued for 10-20 min, the cerium fluoride crude product is washed, and is calcined at a temperature of 500 °C for 1 h to obtain cerium fluoride product.

2. The method for beneficiating calcium from fluorite fluorcarbonatocerite and producing cerium fluoride according to claim 1, characterized in that, In step (3), the mass-volume ratio of the ore powder and the nitric acid solution is 400 g: 100-120 mL.

3. The method for beneficiating bastnaesite containing fluorite and producing cerium fluoride, as claimed in claim 1, wherein, In step (3), 0.1-0.3 wt% polyacrylamide solution is added for flocculation and clarification.

4. The method of claim 1, wherein the method is characterized by, In step (3), 67 wt% nitric acid solution is added, and stirring reaction is carried out at a temperature of 88 °C for 5.5 h.

5. The method of claim 1, wherein the method is characterized by, In step (4), the concentration of ammonia water is 10-30 wt%.

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