阅读说明：本技术 从钠还原钽铌金属废料中分解浸出钽铌的方法 (Method for decomposing and leaching tantalum and niobium from sodium-reduced tantalum-niobium metal waste ) 是由 樊红波 黄水根 胡松 彭小婧 于 2020-07-15 设计创作，主要内容包括：本发明是提供一种从钠还原钽铌金属废料中分解浸出钽铌的方法,是以钠还原钽铌金属废料为原料,包括如下方法步骤混酸处理,催化处理,保温浸出,得到钽铌浸出料。该方法能够有效解决钠还原钽铌金属废料在分解浸出时,因为废料中含有钠元素,与分解液中氟钽酸或氟铌酸反应生成氟钽酸钠或氟铌酸钠沉淀,造成钽铌流失,影响废料中钽铌元素分解浸出率。具有方法简单有效和经济效益明显的特点。(The invention provides a method for decomposing and leaching tantalum and niobium from sodium-reduced tantalum-niobium metal waste, which takes the sodium-reduced tantalum-niobium metal waste as a raw material and comprises the following steps of mixed acid treatment, catalytic treatment and heat preservation leaching to obtain tantalum-niobium leaching material. The method can effectively solve the problem that when the sodium-reduced tantalum-niobium metal waste is decomposed and leached, because the waste contains sodium elements, the waste reacts with the fluorotantalic acid or the fluoroniobate acid in the decomposition liquid to generate sodium fluorotantalate or sodium fluoroniobate precipitate, so that the loss of tantalum-niobium is caused, and the decomposition leaching rate of the tantalum-niobium elements in the waste is influenced. Has the characteristics of simple and effective method and obvious economic benefit.)

1. A method for decomposing and leaching tantalum and niobium from sodium reduced tantalum-niobium metal waste materials is to use the sodium reduced tantalum-niobium metal waste materials as raw materials, and comprises the following steps:

1) mixed acid treatment, namely adding an acid solution into the sodium reduced tantalum-niobium metal waste by taking the sodium reduced tantalum-niobium metal waste as a raw material, fully stirring and mixing to carry out mixed acid treatment to obtain a mixed acid solution of the sodium reduced tantalum-niobium metal waste;

2) performing catalytic treatment, namely adding a catalyst into the mixed acid solution of the sodium-reduced tantalum-niobium metal waste in the previous step, and performing catalytic decomposition leaching treatment under the conditions of heating and heat preservation to obtain a catalytic decomposition leaching mixture solution;

3) and (3) carrying out heat preservation leaching, namely carrying out decomposition leaching treatment on the catalytic decomposition leaching mixture solution in the step 2) for 6-12 hours under the corresponding temperature condition to obtain a tantalum-niobium leaching material.

2. The method as claimed in claim 1, wherein the mass contents of the metal elements in the sodium-reduced tantalum-niobium scrap in step 1) are 40-50 Wt% of niobium pentoxide, 45-52 Wt% of tantalum pentoxide and 4-7 Wt% of sodium; controlling the mass ratio of the sodium-reduced tantalum-niobium metal waste material to the acid solution to be 1: 3-4.5.

3. The method as claimed in claim 1, wherein the acid solution in step 1) is a mixture of hydrofluoric acid and concentrated sulfuric acid, and the volume ratio of the mixture of hydrofluoric acid and concentrated sulfuric acid is controlled to be 3-5: 1; the treatment time of the mixed acid is controlled to be 20-35 hours.

4. The method for the decomposition leaching of tantalum-niobium from sodium-reduced tantalum-niobium scrap material as claimed in claim 1, wherein said catalyst of step 2) is a silica-containing chemical; controlling the adding amount of the catalyst to be 0.5-5 Wt% of the mixed acid solution amount of the sodium-reduced tantalum-niobium metal waste; the heating and heat preservation temperature is 95-105 ℃.

5. The method for decomposing and leaching tantalum and niobium from sodium-reduced tantalum-niobium metal scrap according to claim 1, wherein the temperature of the soaking leaching in the step 3) is 80-95 ℃.

6. The method as claimed in claim 3, wherein said hydrofluoric acid is 50-55 Wt% and said concentrated sulfuric acid is 92.5-98 Wt%.

7. The method as claimed in claim 1 or 4, wherein the catalyst is silica-containing chemical substance selected from quartz sand, and the silica content of the quartz sand is controlled to be 50-100% by mass.

8. The method as claimed in claim 1 or 4, wherein the catalyst is silica-containing chemical substance and the modulus of water glass is controlled to be 2.5-3.5.

The technical field is as follows:

the invention relates to the field of metal smelting, namely tantalum-niobium hydrometallurgy, in particular to a method for decomposing and leaching tantalum-niobium from sodium-reduced tantalum-niobium metal waste.

Background art:

tantalum and niobium belong to rare precious metals, and have the characteristics of high melting point, good corrosion resistance and cold processing performance, so the tantalum and niobium are widely applied to the fields of metallurgical industry, electronic industry, atomic energy, superconducting technology, space navigation and the like, and particularly the tantalum and niobium are indispensable to be removed in national defense and advanced high and new technology departments. With the continuous rise of the demand of China on strategic metals such as tantalum and niobium, the supply of tantalum and niobium resources is greatly challenged.

China is the world with the largest tantalum-niobium hydrometallurgy scale, and the demand of tantalum-niobium raw materials is huge. Although the reserves of tantalum and niobium in China respectively account for more than 10% of the reserves of the total tantalum and niobium in the world, the reserves are abundant, but the tantalum and niobium ores in China have low grade, scattered distribution and associated polymetallic substances, such as the content of tantalum pentoxide and niobium pentoxide is only 0.003-0.02%. The recycling of tantalum and niobium resources is particularly important in China. The sodium reduction tantalum-niobium metal waste is waste generated in the process of preparing tantalum-niobium metal by sodium reduction, and leftover materials contain partial sodium elements. When the waste is decomposed and leached, sodium in the waste reacts with the fluotantalic acid or the fluoniobate acid in the decomposition liquid to generate sodium fluotantalate or sodium fluoniobate precipitate, and the sodium fluotantalate or the sodium fluoniobate precipitate enters decomposition slag to cause loss, so that the decomposition and leaching rate of the tantalum-niobium element in the waste is influenced.

For example, Chinese patent publication No. CN 103160684A discloses a method for extracting tantalum and niobium by decomposing tantalum-niobium ore with low alkali, which comprises roasting and decomposing tantalum-niobium ore by using a small amount of sodium hydroxide as a fusing agent to convert tantalum and niobium into sodium metatantalate and sodium metaniobate. And then leaching tantalum and niobium in the roasted product by using dilute hydrofluoric acid at a lower temperature under the condition of adding a transformation agent to obtain ore pulp containing the fluorine tantalic acid and the fluorine niobate acid. However, the method takes tantalum-niobium ore as raw material to extract and separate tantalum and niobium. Instead of recovering tantalum and niobium by using the metal scrap of sodium-reduced tantalum and niobium as a raw material.

Therefore, how to provide a method for decomposing and leaching tantalum and niobium from sodium-reduced tantalum-niobium metal waste, which takes the sodium-reduced tantalum-niobium metal waste as a raw material; the technical problems that the decomposition leaching rate of the tantalum-niobium element in the waste material is influenced and the like because sodium element in the waste material reacts with the fluorotantalic acid or the fluoroniobate acid in the decomposition liquid to generate sodium fluorotantalate or sodium fluoroniobate precipitate which enters the decomposition slag to cause loss when the sodium element is decomposed and leached are solved.

The invention content is as follows:

the invention discloses a method for decomposing and leaching tantalum and niobium from sodium reduced tantalum-niobium metal waste, which takes the sodium reduced tantalum-niobium metal waste as a raw material and comprises the following steps of mixed acid treatment, catalytic treatment and heat preservation leaching to obtain tantalum-niobium leaching material. The method can effectively solve the problem that when the sodium-reduced tantalum-niobium metal waste is decomposed and leached, because the waste contains sodium elements, the waste reacts with the fluorotantalic acid or the fluoroniobate acid in the decomposition liquid to generate sodium fluorotantalate or sodium fluoroniobate precipitate, so that the loss of tantalum-niobium is caused, and the decomposition leaching rate of the tantalum-niobium elements in the waste is influenced. Has the characteristics of simple and effective method and obvious economic benefit.

The invention discloses a method for decomposing and leaching tantalum and niobium from sodium reduced tantalum-niobium metal waste, which takes the sodium reduced tantalum-niobium metal waste as a raw material and comprises the following steps:

1) mixed acid treatment, namely adding an acid solution into the sodium reduced tantalum-niobium metal waste by taking the sodium reduced tantalum-niobium metal waste as a raw material, fully stirring and mixing to carry out mixed acid treatment to obtain a mixed acid solution of the sodium reduced tantalum-niobium metal waste;

2) performing catalytic treatment, namely adding a catalyst into the mixed acid solution of the sodium-reduced tantalum-niobium metal waste in the previous step, and performing catalytic decomposition leaching treatment under the conditions of heating and heat preservation to obtain a catalytic decomposition leaching mixture solution;

3) and (3) carrying out heat preservation leaching, namely carrying out decomposition leaching treatment on the catalytic decomposition leaching mixture solution in the step 2) for 6-12 hours under the corresponding temperature condition to obtain a tantalum-niobium leaching material.

The method for decomposing and leaching tantalum and niobium from sodium-reduced tantalum-niobium metal waste comprises the following steps of 1) enabling the mass content of all metal elements in the sodium-reduced tantalum-niobium metal waste to be 40-50 Wt% of niobium pentoxide, 45-52 Wt% of tantalum pentoxide and 4-7 Wt% of sodium; controlling the mass ratio of the sodium-reduced tantalum-niobium metal waste material to the acid solution to be 1: 3-4.5.

The method for decomposing and leaching tantalum and niobium from sodium-reduced tantalum-niobium metal waste material is characterized in that in the step 1), the acid solution is a mixture of hydrofluoric acid and concentrated sulfuric acid, and the volume ratio of the mixture of the hydrofluoric acid and the concentrated sulfuric acid is controlled to be 3-5: 1; the treatment time of the mixed acid is controlled to be 20-35 hours.

Preferably, the catalyst of step 2) is a silica-containing chemical; controlling the adding amount of the catalyst to be 0.5-5 Wt% of the mixed acid solution amount of the sodium-reduced tantalum-niobium metal waste; the heating and heat preservation temperature is 95-105 ℃.

Further, the temperature of the heat preservation leaching in the step 3) is 80-95 ℃.

Preferably, the concentration of the hydrofluoric acid is 50-55 Wt%, and the mass concentration of the concentrated sulfuric acid is 92.5-98 Wt%.

Preferably, the catalyst is quartz sand containing silicon dioxide chemical substance, and the mass content of silicon dioxide in the quartz sand is controlled to be 50-100%

Furthermore, the catalyst is silicon dioxide-containing chemical substance which is water glass, and the modulus of the water glass is controlled to be 2.5-3.5.

The invention discloses a method for decomposing and leaching tantalum and niobium from sodium-reduced tantalum-niobium metal waste, wherein the decomposition leaching rate is calculated by adopting the following method: (tantalum or niobium content in titanium tantalum ore powder-residual tantalum or niobium content after ore powder leaching is completed) ÷ tantalum or niobium content in titanium tantalum ore powder is multiplied by 100%; the tantalum or niobium content in the titanium-tantalum ore powder refers to the tantalum or niobium content in the raw material of tantalum-niobium metal waste reduced by sodium, and the same is applied below.

The invention discloses a method for decomposing and leaching tantalum and niobium from sodium-reduced tantalum-niobium metal waste, which has the beneficial effects that:

the method comprises the steps of adding sodium-reduced tantalum-niobium metal waste into mixed acid of hydrofluoric acid and sulfuric acid, and adding a certain amount of corresponding decomposition leaching catalyst which mainly comprises silicon dioxide with the silicon dioxide content of about 65% after the addition is finished; the sodium fluosilicate precipitate can be generated by reaction with hydrofluoric acid and sodium, so that sodium in the waste is removed, the influence of the sodium on the decomposition and leaching of the tantalum-niobium element is avoided, and the decomposition and leaching of the tantalum-niobium element in the sodium reduction tantalum-niobium metal waste can be completed by heat preservation decomposition and leaching for more than 8 hours. In conclusion, the method can solve the problem of influence of sodium in the sodium-reduced tantalum-niobium metal waste on the decomposition leaching rate of the tantalum-niobium element, improves the decomposition leaching rate of the tantalum-niobium element, and has the characteristics of simplicity, effectiveness and obvious economic benefit. Through detection, the decomposition leaching rate of niobium pentoxide in the sodium-reduced tantalum-niobium metal waste is over 99.5%, the decomposition leaching rate of tantalum pentoxide is over 98.9%, the decomposition leaching rate is ideal, and most of tantalum and niobium elements in the waste can be decomposed and leached.

The specific implementation mode is as follows:

the invention discloses a method for decomposing and leaching tantalum and niobium from sodium reduced tantalum-niobium metal waste, which takes the sodium reduced tantalum-niobium metal waste as a raw material and comprises the following steps:

1) mixed acid treatment, namely adding an acid solution into sodium reduced tantalum-niobium metal waste by taking the sodium reduced tantalum-niobium metal waste as a raw material, fully stirring and mixing to perform mixed acid treatment, wherein the mass content of each metal element in the sodium reduced tantalum-niobium metal waste is that the content of niobium pentoxide is 40-50 Wt%, the content of tantalum pentoxide is 45-52 Wt%, and the content of sodium is 4-7 Wt%; controlling the mass ratio of the sodium-reduced tantalum-niobium metal waste material to the acid solution to be 1: 3-4.5; the acid solution is a mixture of hydrofluoric acid and concentrated sulfuric acid, and the volume ratio of the mixture of the hydrofluoric acid and the concentrated sulfuric acid is controlled to be 3-5: 1; controlling the treatment time of the mixed acid to be 20-35 hours; the concentration of the hydrofluoric acid is 50-55 Wt%, and the mass concentration of the concentrated sulfuric acid is 92.5-98 Wt%; obtaining mixed acid solution of sodium-reduced tantalum-niobium metal waste;

2) performing catalytic treatment, namely adding a catalyst into the mixed acid solution of the sodium-reduced tantalum-niobium metal waste in the previous step, wherein the catalyst is a chemical substance containing silicon dioxide; controlling the adding amount of the catalyst to be 0.5-5 Wt% of the mixed acid solution amount of the sodium-reduced tantalum-niobium metal waste; under the condition of heating and heat preservation, the heating and heat preservation temperature is 95-105 ℃. Carrying out catalytic decomposition leaching treatment to obtain a catalytic decomposition leaching mixture solution;

3) and (3) carrying out heat preservation leaching, namely decomposing and leaching the catalytic decomposition leaching mixture solution in the step 2) for 6-12 hours at the temperature of 80-95 ℃ to obtain a tantalum-niobium leaching material.

Preferably, the catalyst is silica-containing chemical substance which is quartz sand, and the mass content of silica in the quartz sand is controlled to be 50-100%; preferably, the catalyst can also be a silicon dioxide-containing chemical substance which is water glass, and the modulus of the water glass is controlled to be 2.5-3.5.

By utilizing the method, through measurement and calculation, the decomposition leaching rate of niobium pentoxide in the sodium-reduced tantalum-niobium metal waste can reach 99.5%, the decomposition leaching rate of tantalum pentoxide can reach 98.9%, the decomposition leaching rate is ideal, and most of tantalum-niobium elements in the waste can be decomposed and leached.