阅读说明：本技术 一种湿法冶炼氟碳钙铈矿的方法 (Method for smelting bastnaesite by wet process ) 是由 许思玉 张�荣 朱光荣 冯新瑞 于 2021-06-29 设计创作，主要内容包括：本发明公开了一种湿法冶炼氟碳钙铈矿的方法,属于氟碳铈矿的冶炼分离技术领域。解决了现有技术中氟碳钙铈矿中的碱土金属难以通过选矿方法除去的问题。本发明包括以下步骤：1、将含碱土金属的氟碳钙铈矿氧化焙烧至半融状态,得到氧化矿物；2、将氧化矿物缓慢加入到装有盐酸的烧杯中进行搅拌反应；3、反应完成后向体系中加入聚丙烯酰胺进行絮凝沉淀,然后固液分离,得到氯化稀土溶液和未能溶于盐酸的氟碳铈矿残渣；4、将氯化稀土溶液升温到80-90℃,缓慢加入30％的氨水进行回调PH值除杂,得到清亮透明的氯化稀土料液。本发明使氟与碱土金属在高温条件下发生固化反应,从而将碱土金属去除,然后通过选择性一步浸出使稀土收率提高到96％以上。(The invention discloses a method for smelting bastnaesite by a wet method, belonging to the technical field of smelting separation of bastnaesite. Solves the problem that the alkaline earth metal in the bastnaesite is difficult to remove by the mineral separation method in the prior art. The invention comprises the following steps: 1. oxidizing and roasting the bastnaesite containing the alkaline-earth metal to a semi-molten state to obtain an oxidized mineral; 2. slowly adding the oxidized minerals into a beaker filled with hydrochloric acid to carry out stirring reaction; 3. adding polyacrylamide into the system after the reaction is finished for flocculation and precipitation, and then carrying out solid-liquid separation to obtain a rare earth chloride solution and bastnaesite residues which cannot be dissolved in hydrochloric acid; 4. heating the rare earth chloride solution to 80-90 ℃, slowly adding 30% ammonia water to adjust the pH value back for impurity removal, and obtaining clear and transparent rare earth chloride feed liquid. The invention makes fluorine and alkaline earth metal generate solidification reaction under high temperature condition, thereby removing the alkaline earth metal, and then the rare earth yield is improved to more than 96% through selective one-step leaching.)

1. A method for smelting bastnaesite by a wet method is characterized by comprising the following steps:

step 1: placing the bastnaesite containing the alkaline-earth metal in a muffle furnace for oxidizing roasting to a semi-molten state to obtain an oxidized mineral;

step 2: slowly adding the oxidized minerals into a beaker filled with hydrochloric acid to carry out stirring reaction;

and step 3: after the reaction in the step 2 is finished, adding polyacrylamide into the system for flocculation and precipitation, and then carrying out solid-liquid separation to obtain a rare earth chloride solution and bastnaesite residues which cannot be dissolved in hydrochloric acid;

and 4, step 4: heating the rare earth chloride solution to 80-90 ℃, slowly adding 30% ammonia water to adjust the pH value back for impurity removal, and obtaining clear and transparent rare earth chloride feed liquid.

2. The method for hydrometallurgical production of bastnaesite as claimed in claim 1, wherein the temperature in the muffle furnace in step 1 is 900-1100 ℃, and the calcination time is 3-5 h.

3. The method for hydrometallurgical processing of bastnaesite according to claim 1, wherein the concentration of hydrochloric acid in step 2 is 25% to 32%.

4. The method as claimed in claim 1, wherein the reaction temperature in step 2 is not higher than 30 ℃, the residual acidity of the reaction is 2-3mol/L, the rare earth concentration in the feed liquid is 220-280g/L, and the reaction time is 8-12 h.

5. The method for hydrometallurgical production of bastnaesite according to claim 1, wherein the PH adjusted back in step 4 is 4.5.

6. The method for hydrometallurgical processing of bastnaesite according to claim 1, further comprising the step of 5: and (4) washing and drying the bastnaesite residue obtained in the step (4).

Technical Field

The invention belongs to the technical field of bastnaesite smelting separation, and particularly relates to a method for smelting bastnaesite by a wet method.

Background

Bastnaesite is one of the most widely distributed rare earth minerals, and is commonly produced in rare metal carbonate-alkaline miscellaneous rocks, granite and granite pegmatite; calcite-quartz veins associated with granite syenite; bastnaesite, which is a surface-producing cause, is found in alkaline rock weathering shells and clays. Bastnaesite can be symbiotic with bastnaesite to form single bastnaesite type rare earth ore, and often symbiotic or concomitant with rare earth minerals such as monazite, niobium minerals, iron minerals, and the like.

The bastnaesite is associated with barite, fluorite, limestone and the like, and single flotation-separation or flotation-gravity separation-flotation combined flow is adopted to obtain the bastnaesite concentrate, the rare earth grade in the concentrate is between 55 and 65 percent, the lower the rare earth grade, the higher the impurities such as non-rare earth impurity alkaline earth metal and the like are, the calcium content can reach 10 to 15 percent, the strontium content can reach 4.0 to 6.0 percent, the barium content can reach 3.0 to 5.0 percent, and the alkaline earth metal in the associated bastnaesite is difficult to remove by a mineral separation method.

Disclosure of Invention

Aiming at the problem that alkaline earth metals in bastnaesite are difficult to remove by a beneficiation method in the prior art, the invention provides a method for smelting bastnaesite by a wet method, which aims to: .

The technical scheme adopted by the invention is as follows:

a method for hydrometallurgical smelting of bastnaesite comprises the following steps:

step 1: placing the bastnaesite containing the alkaline-earth metal in a muffle furnace for oxidizing roasting to a semi-molten state to obtain an oxidized mineral;

step 2: slowly adding the oxidized minerals into a beaker filled with hydrochloric acid to carry out stirring reaction;

and step 3: after the reaction in the step 2 is finished, adding polyacrylamide into the system for flocculation and precipitation, and then carrying out solid-liquid separation to obtain a rare earth chloride solution and bastnaesite residues which cannot be dissolved in hydrochloric acid;

and 4, step 4: heating the rare earth chloride solution to 80-90 ℃, slowly adding 30% ammonia water to adjust the pH value back for impurity removal, and obtaining clear and transparent rare earth chloride feed liquid.

Preferably, the temperature in the muffle furnace in the step 1 is 900-.

Preferably, the concentration of hydrochloric acid in step 2 is 25% to 30%.

Preferably, the reaction temperature in the step 2 is not higher than 30 ℃, the residual acidity of the reaction is 2-3mol/L, the rare earth concentration in the feed liquid is 220-280g/L, and the reaction time is 8-12 h.

Preferably, the pH value after the adjustment in step 4 is 4.5.

Preferably, the method further comprises the step 5: and (4) washing and drying the bastnaesite residue obtained in the step (4).

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

1. the method carries out oxidation burning on the bastnaesite to a semi-molten state under the high-temperature condition, and fluorine and elements such as alkaline earth metal and the like carry out a curing reaction in the oxidation burning process to obtain a substance which is difficult to dissolve in dilute hydrochloric acid, so that the alkaline earth metal can be removed in a selective leaching way.

2. In the process of hydrochloric acid wet dissolution, technological conditions such as temperature, acidity and time are strictly controlled to carry out selective one-step leaching, so that fluorine and alkaline earth metal are not dissolved, only rare earth oxide and a small amount of non-rare earth impurities are leached, alkaline substance ammonia water is added into the solution obtained by reaction, the pH value is adjusted back to 4.5, ferric ions and aluminum ions in the solution are removed, clear and transparent rare earth chloride solution is obtained, the rare earth chloride solution enters the next step for extraction and separation, and is separated into single rare earth chloride solution, and the rare earth yield reaches over 96%.

3. The fluorine carbon calcium cerium slag can be washed, dried and sold, so that the economic benefit is improved.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the attached tables in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments. Thus, the following detailed description of the embodiments of the present application, as presented in the accompanying tables, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present application without making any creative effort, shall fall within the protection scope of the present application.

Example 1:

firstly, 1000g of bastnaesite raw ore is taken for standby, and the components of the bastnaesite raw ore are analyzed and detected.

Detecting items	REO	CaO	SrO	BaO	F
						Results (%)	56.3％	10.86	3.46	4.28	5.69

Secondly, adjusting the temperature of the muffle furnace to 900 ℃, and placing 1000g of the hamartite raw bastnaesite ore into the muffle furnace for oxidizing roasting for 5 hours. After the completion of calcination, the calcined product was weighed with a balance to obtain 863 g.

And thirdly, measuring 1400ml of 32% hydrochloric acid by using a measuring cylinder, adding the hydrochloric acid into a 2000ml beaker, and weighing 600g of the high-temperature oxidation roasted mineral for later use by using a balance.

And fourthly, slowly adding 600g of the weighed oxidized minerals into a 2000ml beaker filled with the hydrochloric acid for stirring reaction, controlling the reaction temperature to be not higher than 30 ℃, controlling the reaction time to be 12 hours, and detecting that the residual acidity is 2.89 mol/L and the rare earth concentration of the feed liquid is 236.5g/L after the reaction is finished.

Fifthly, adding polyacrylamide into the system after the reaction is finished, and performing solid-liquid separation after flocculation and clarification to obtain a rare earth chloride solution and bastnaesite residue which cannot be dissolved in hydrochloric acid. 180.89g is obtained after the bastnaesite residue is washed and dried, the rare earth grade in the bastnaesite residue is measured to be 6.89%, and the rare earth leaching rate is calculated to be 96.79% through data analysis.

Sixthly, heating the obtained rare earth chloride solution to 85 ℃, slowly adding 264ml of 30% ammonia water, adjusting the pH value back to 4.5, removing ferric ions and aluminum ions in the solution, removing impurities, and then feeding clear and transparent rare earth feed liquid into the next step to serve as an extraction separation raw material of a single rare earth product.

Example 2

Firstly, 1000g of bastnaesite raw ore is taken for standby, and the components of the bastnaesite raw ore are analyzed and detected.

Detecting items	REO	CaO	SrO	BaO	F
						Results (%)	65.6％	6.67	2.23	2.38	6.67

Secondly, adjusting the temperature of the muffle furnace to 1000 ℃, and placing 1000g of the hamartite raw bastnaesite ore into the muffle furnace for oxidizing roasting for 4.5 hours. After completion of calcination, the calcined product was weighed with a balance to obtain 836 g.

And thirdly, measuring 1600ml of 25% hydrochloric acid by using a measuring cylinder respectively, adding the hydrochloric acid into a 2000ml beaker, and weighing 600g of the high-temperature oxidation-roasted mineral for later use by using a balance.

And fourthly, slowly adding 600g of the weighed oxidized minerals into a 2000ml beaker filled with the hydrochloric acid for stirring reaction, controlling the reaction temperature to be not higher than 30 ℃, controlling the reaction time to be 8 hours, and detecting that the residual acidity is 2.21 mol/L and the concentration of the rare earth feed liquid is 273.6g/L after the reaction is finished.

Fifthly, adding polyacrylamide into the system after the reaction is finished, and performing solid-liquid separation after flocculation and clarification to obtain a rare earth chloride solution and bastnaesite residue which cannot be dissolved in hydrochloric acid. 146.32g is obtained after the bastnaesite residue is washed and dried, the rare earth grade in the bastnaesite residue is measured to be 9.32%, and the rare earth leaching rate is 97.11% through data analysis and calculation.

Sixthly, heating the rare earth chloride solution to 88 ℃, slowly adding 213ml of 30% ammonia water, adjusting the pH value back to 4.5, removing ferric ions and aluminum ions, removing impurities, and then feeding clear and transparent rare earth feed liquid into the next process to be used as an extraction separation raw material of a single rare earth product.

Example three:

firstly, 1000g of bastnaesite raw ore is taken for standby, and is analyzed and detected.

Detecting items	REO	CaO	SrO	BaO	F
						Results (%)	62.6％	8.35	2.96	3.06	6.09

Secondly, adjusting the temperature of the muffle furnace to 1000 ℃, and placing 1000g of the hamartite raw bastnaesite ore into the muffle furnace for oxidizing roasting for 4 hours. After completion of the calcination, the calcined product was weighed with a balance to obtain 849 g.

And thirdly, measuring 1500ml of 30% hydrochloric acid by using a measuring cylinder respectively, adding the hydrochloric acid into a 2000ml beaker, and weighing 600g of the mineral subjected to high-temperature oxidation burning for later use by using a balance.

And fourthly, slowly adding 600g of the weighed oxidized minerals into a 2000ml beaker filled with the hydrochloric acid for stirring reaction, controlling the reaction temperature to be not higher than 30 ℃, controlling the reaction time to be 10.5h, and detecting that the residual acidity is 2.85 mol/L and the concentration of the rare earth feed liquid is 258.96g/L after the reaction is finished.

Fifthly, adding polyacrylamide into the system after the reaction is finished, flocculating and clarifying, and carrying out solid-liquid separation to obtain a rare earth chloride solution and bastnaesite residue which cannot be dissolved in hydrochloric acid. 153.68g of bastnaesite residues are obtained after washing and drying, the rare earth grade is 7.02 percent, and the rare earth leaching rate is 97.56 percent through data analysis calculation.

Sixthly, heating the obtained rare earth chloride solution to 90 ℃, slowly adding 246ml of 30% ammonia water, adjusting the pH value to 4.5, removing ferric ions and aluminum ions, and feeding clear and transparent rare earth feed liquid obtained after impurity removal into the next process to be used as an extraction separation raw material of a single rare earth product.

And (4) conclusion: oxidizing and burning over 6 percent of bastnaesite containing alkaline earth metal for 3-5h at the temperature of 900-1100 ℃ to a semi-molten state, wherein the fluorocarbon is firstly oxidized and decomposed into rare earth oxide, rare earth oxyfluoride and rare earth fluoride, and then the fluorine gradually reacts with the alkaline earth metal along with the rise of the temperature to be solidified, so as to obtain a substance which is difficult to dissolve in dilute hydrochloric acid. The product of the oxidation ignition is leached by a hydrochloric acid wet method, the reaction temperature is strictly controlled not to exceed 30 ℃, the reaction residual acidity is 2-3mol/L, the reaction time is 8-12h, the rare earth concentration in the material liquid is 280g/L and other process conditions are adopted for selective one-step leaching, then solid-liquid separation is carried out, alkaline substance ammonia water is added into the material liquid obtained by the reaction, the PH is adjusted to 4.5, impurity removal is carried out, mixed material liquid for extraction separation is obtained, the slag is washed by water and dried, and then the residue is sold, and the rare earth yield reaches more than 96%.

The above-mentioned embodiments only express the specific embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present application. It should be noted that, for those skilled in the art, without departing from the technical idea of the present application, several changes and modifications can be made, which are all within the protection scope of the present application.