阅读说明：本技术 一种从辉锑矿中制备锑酸钠的方法 (Method for preparing sodium antimonate from stibnite ) 是由 谢刚 俞小花 杨帆 沈庆峰 李永刚 史淯升 田林 杨妮 任玖阳 于 2020-05-20 设计创作，主要内容包括：本发明属于冶金技术领域,具体涉及一种从辉锑矿中制备锑酸钠的方法。本发明提供的从辉锑矿中制备锑酸钠的方法,包括以下步骤：提供辉锑矿粉料；利用混合液对所述辉锑矿粉料进行浸出,固液分离后得到浸出液；所述混合液包括硫化钠、氢氧化钠和水,所述浸出液包括Na-3SbS-3；将所述浸出液与碱混合,在氧化性气氛下进行沉锑反应,得到锑酸钠。实验结果表明,采用本发明提供的方法,锑的浸出率达到96.31～99.56％,沉锑率达到95.87～99.32％,三价锑含量仅0.05～0.18％,白度达到85～96％。(The invention belongs to the technical field of metallurgy, and particularly relates to a method for preparing sodium antimonate from stibnite. The invention provides a method for preparing sodium antimonate from stibnite, which comprises the following steps: providing stibnite powder; leaching the stibnite powder by using a mixed solution, and performing solid-liquid separation to obtain a leaching solution; the mixed liquor comprises sodium sulfide, sodium hydroxide and water, and the leaching liquor comprises Na 3 SbS 3 (ii) a And mixing the leaching solution with alkali, and carrying out antimony precipitation reaction in an oxidizing atmosphere to obtain the sodium antimonate. Experimental results show that by adopting the method provided by the invention, the leaching rate of antimony reaches 96.31-99.56%, the antimony precipitation rate reaches 95.87-99.32%, the content of trivalent antimony is only 0.05-0.18%, and the whiteness reaches 85-96%.)

1. A method for preparing sodium antimonate from stibnite is characterized by comprising the following steps:

providing stibnite powder;

leaching the stibnite powder by using a mixed solution, and performing solid-liquid separation to obtain a leaching solution; the mixed liquor comprises sodium sulfide, sodium hydroxide and water, and the leaching liquor comprises Na₃SbS₃；

And mixing the leaching solution with alkali, and carrying out antimony precipitation reaction in an oxidizing atmosphere to obtain the sodium antimonate.

2. The method of claim 1, wherein the particle size of the stibnite dust is 0.6mm or less.

3. The method according to claim 1, wherein the concentration of sodium sulfide in the mixed solution is 80-120 g/L, and the concentration of sodium hydroxide is 20-50 g/L; the solid-liquid ratio of leaching is 1: (2-4).

4. The method according to claim 1 or 3, wherein the leaching temperature is 50-90 ℃ and the leaching time is 30-45 min.

5. The method of claim 1, wherein the base is sodium hydroxide.

6. A process according to claim 3, wherein the molar ratio of alkali to leach liquor is (1.4 to 1.8): 1.

7. the method according to claim 1, wherein the temperature of the antimony precipitation reaction is 120-150 ℃ and the time is 2-4 h; the environmental pressure of the antimony precipitation reaction is 0.6-1.4 MPa.

8. The method of claim 1, wherein the gas providing the oxidizing atmosphere is one or more of oxygen, disulfur trioxide, and ozone.

Technical Field

The invention belongs to the technical field of metallurgy, and particularly relates to a method for preparing sodium antimonate from stibnite.

Background

In the hydrometallurgy of antimony, the antimony in single antimony sulfide ores (e.g., stibnite) or multi-metal complex antimony sulfide ores (e.g., tetrahedrite) is treated with Na, usually under alkaline sodium sulfide system conditions₃SbS₃The form of the gangue enters a leaching solution to selectively separate gangue and other valuable metals (such as copper, lead, gold and the like); for the leaching solution of antimony sulfide ore, metal antimony can be prepared by electrodeposition, but the method has the defects of high power consumption and large alkali fog; or the antimony can be directly oxidized and precipitated from the leaching solution to prepare the sodium antimonate. At present, the preparation method of sodium antimonate mainly comprises the research of synthesizing sodium antimonate by a hydrogen peroxide oxidation method (Zhang Yongwar, Liujin shield, Zhang Xiangping, Wanyazhen, one-step method [ J]Henan chemical, 1998 (02): 22-23+26), intensified jet oxidation (datongming, jiangdejian, et al. intensified jet oxidation for sodium antimonate. CN1117024A.1996.12) and air oxidation catalyst-adding method (Tangjian force. air oxidation for antimony precipitation of sodium thioantimonate solution [ D)]In Hunan province: university of central and south; zhongnan university of industry, 1999), but these methods have the disadvantages of high cost or too long oxidation process, and the above methods do not easily ensure the oxide concentration, and easily cause the problems of long oxidation time and incomplete antimony separation due to high content of trivalent antimony in the product.

Disclosure of Invention

In view of the above, the present invention aims to provide a method for preparing sodium antimonate from stibnite, which has the characteristics of short oxidation time, low cost and complete separation of antimony.

In order to achieve the purpose of the invention, the invention provides the following technical scheme:

the invention provides a method for preparing sodium antimonate from stibnite, which comprises the following steps:

providing stibnite powder;

leaching the stibnite powder by using a mixed solution, and performing solid-liquid separation to obtain a leaching solution; the mixed liquor comprises sodium sulfide, sodium hydroxide and water, and the leaching liquor comprises Na₃SbS₃；

And mixing the leaching solution with alkali, and carrying out antimony precipitation reaction in an oxidizing atmosphere to obtain the sodium antimonate.

Preferably, the particle size of the stibnite powder is less than or equal to 0.6 mm.

Preferably, the concentration of sodium sulfide in the mixed solution is 80-120 g/L, and the concentration of sodium hydroxide is 20-50 g/L; the solid-liquid ratio of leaching is 1: (2-4).

Preferably, the leaching temperature is 50-90 ℃, and the leaching time is 30-45 min.

Preferably, the solute of the alkaline solution is sodium hydroxide.

Preferably, the molar ratio of the alkali to the leaching solution is (1.4-1.8): 1.

preferably, the temperature of the antimony precipitation reaction is 120-150 ℃, and the time is 2-4 h; the environmental pressure of the antimony precipitation reaction is 0.6-1.4 MPa.

Preferably, the gas providing the oxidizing atmosphere is one or more of oxygen, disulfide trioxide and ozone.

The invention provides a method for preparing sodium antimonate from stibnite, which comprises the following steps: providing stibnite powder; leaching the stibnite powder by using a mixed solution, and performing solid-liquid separation to obtain a leaching solution; the mixed liquor comprises sodium sulfide, sodium hydroxide and water, and the leaching liquor comprises Na₃SbS₃(ii) a And mixing the leaching solution with an alkaline solution, and carrying out antimony precipitation reaction in an oxidizing atmosphere to obtain the sodium antimonate. In the invention, the antimony precipitation reaction is carried out under the condition of oxidizing atmosphere, so that the antimony precipitation reaction occurs on the interface of the leaching solution and the oxidizing gas; meanwhile, the oxidizing atmosphere gas is used for increasing the environmental pressure of antimony precipitation reaction, and the principle of dynamics shows that the oxygen potential in the reaction system can be improved by increasing the introducing pressure of the oxidizing atmosphere gas, the pressure difference of the gas-liquid phase surface of the reaction system is improved, and the oxidizing atmosphere is acceleratedThe diffusion rate of the gas is beneficial to shortening the oxidation time and improving the oxidation efficiency, so that the method provided by the invention can greatly shorten the antimony precipitation time compared with the common oxidation method in the prior art; meanwhile, the antimony precipitation reaction is carried out under the condition of oxidizing atmosphere, so that Sb in the leaching solution can be enabled to be³⁺Sufficiently oxidized to Sb in a relatively short time⁵⁺And due to Sb³⁺Is soluble, and Sb⁵⁺Is insoluble, thereby greatly reducing Sb in a solution system³⁺The Sb is effectively separated from other impurity ions in the solution, and the Sb carried in the precipitate can be effectively separated³⁺The control is in a lower range, which is beneficial to improving the resource recovery rate of Sb and obtaining a better-grade sodium antimonate product.

Experimental results show that by adopting the method provided by the invention, the leaching rate of antimony reaches 96.31-99.56%, the antimony precipitation rate reaches 95.87-99.32%, the mass content of trivalent antimony is only 0.05-0.18%, and the whiteness reaches 85-96%.

Detailed Description

The invention provides a method for preparing sodium antimonate from stibnite, which comprises the following steps:

providing stibnite powder;

leaching the stibnite powder by using a mixed solution, and performing solid-liquid separation to obtain a leaching solution; the mixed liquor comprises sodium sulfide, sodium hydroxide and water, and the leaching liquor comprises Na₃SbS₃；

And mixing the leaching solution with alkali, and carrying out antimony precipitation reaction in an oxidizing atmosphere to obtain the sodium antimonate.

In the present invention, unless otherwise specified, commercially available products well known to those skilled in the art are used for each component in the method.

The invention provides stibnite powder.

In the invention, the particle size of the stibnite powder is preferably less than or equal to 0.6mm, and more preferably 0.18-0.6 mm. The source of the stibnite is not particularly limited in the present invention, and may be any source known to those skilled in the art. In the present invention, the stibnite dust is preferably commercially available or obtained by processing stibnite ore. In the present invention, the processing of the stibnite ore is preferably performed by sequentially subjecting the stibnite ore to mechanical crushing and ball milling. In the present invention, the mechanical crushing is preferably jaw crushing. The jaw crushing method of the present invention is not particularly limited, and jaw crushing known to those skilled in the art may be used. The ball milling is not particularly limited in the present invention, so that the particle size of the powder of stibnite can satisfy the above particle size range. In the present invention, the chemical composition of the stibnite preferably comprises Sb 10-40 wt.%, S7-35 wt.% and the balance impurities; the present invention is not particularly limited with respect to the kind of the impurities, and the impurities of stibnite known in the art are used as the standard.

After providing stibnite powder, leaching the stibnite powder by using a mixed solution, and performing solid-liquid separation to obtain a leachate; the mixed liquid comprises sodium sulfide, sodium hydroxide and water.

In the invention, the concentration of sodium sulfide in the mixed solution is preferably 80-120 g/L, more preferably 85-115 g/L; the concentration of the sodium hydroxide in the mixed solution is preferably 20-50 g/L, and more preferably 25-45 g/L. In the present invention, the solid-to-liquid ratio of the leaching is preferably 1: (2-4), more preferably 1: (2.5-3.5). In the invention, the sodium hydroxide can inhibit the hydrolysis of sodium sulfide, and is beneficial to improving the effective amount of sodium sulfide capable of participating in the reaction in a leaching system.

In the invention, the leaching temperature is preferably 50-90 ℃, and more preferably 55-85 ℃; the time is preferably 30 to 45min, and more preferably 35 to 40 min.

In the present invention, the leaching is preferably performed under stirring. The stirring rate is not particularly limited in the present invention, and a stirring rate known to those skilled in the art may be used.

In the present invention, the leaching is reacted: sb₂S₃+3Na₂S＝2Na₃SbS₃。

In the present invention, the leachate includes Na₃SbS₃。

The invention has no special characteristics on the solid-liquid separationThe method is very limited, and the solid-liquid separation operation well known to the skilled person can be adopted. After leaching, carrying out solid-liquid separation to obtain solid slag and a leaching solution; the leaching solution contains Na₃SbS₃。

After the leaching solution is obtained, the leaching solution is mixed with alkali, and antimony precipitation reaction is carried out in an oxidizing atmosphere to obtain the sodium antimonate.

In the present invention, the base is preferably sodium hydroxide. In the invention, the molar ratio of the alkali to the leaching solution is preferably (1.4-1.8): 1, more preferably (1.5 to 1.7): 1. in the present invention, the base is preferably provided in the form of a solid or a solution. In the invention, when the alkali is provided in the form of a solution, the concentration of the alkali solution formed by the alkali is preferably 250-350 g/L, and more preferably 280-320 g/L. In the invention, the volume ratio of the leaching solution to the alkaline solution is preferably (10-20): 1, more preferably (12-15): 1.

in the present invention, the gas providing the oxidizing atmosphere is preferably one or more of oxygen, disulfide trioxide and ozone. In the present invention, the oxidizing atmosphere is preferably provided by introducing an oxidizing gas into the leach solution.

In the invention, the temperature of the antimony precipitation reaction is preferably 120-150 ℃, and more preferably 125-145 ℃; the time is preferably 2 to 4 hours, and more preferably 2.5 to 3.5 hours. In the invention, the environmental pressure of the antimony precipitation reaction is preferably 0.6-1.4 MPa, and more preferably 0.8-1.2 MPa. In the present invention, the ambient pressure of the antimony precipitation reaction is preferably provided by the introduction pressure of an oxidizing atmosphere gas. In the present invention, the apparatus for the antimony precipitation reaction is preferably an autoclave.

In the invention, Na is generated in the antimony precipitation reaction₃SbS₃Is oxidized into Na under the condition of alkaline and oxidizing atmosphere₂S₂O₃. Taking an oxidizing atmosphere gas as an example of oxygen, the following reaction occurs:

2Na₃SbS₃(aq)+7O₂(g)+2NaOH(aq)+5H₂O＝2NaSb(OH)₆(S)+3Na₂S₂O₃(aq)。

after the antimony precipitation reaction, the invention preferably further comprises solid-liquid separation, and the obtained solid is the sodium antimonate. The solid-liquid separation is not particularly limited in the present invention, and a solid-liquid separation known to those skilled in the art may be employed.

To further illustrate the present invention, the following examples are provided to describe in detail a method for preparing sodium antimonate from stibnite according to the present invention, but they should not be construed as limiting the scope of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The reagents used in the examples are all commercially available.

Example 1

The chemical composition of stibnite comprises: SiO 2₂63.77 wt.%, Sb 19.82 wt.%, S12.15 wt.%, fe2.73wt.%, Al 0.71 wt.%, and As 0.39 wt.%.

Crushing stibnite ores, and ball-milling until the granularity is 0.18mm to obtain stibnite powder;

preparing a mixed solution, wherein the concentration of sodium sulfide in the mixed solution is 80g/L, and the concentration of sodium hydroxide is 40 g/L; according to the solid-liquid ratio of 1: 4, leaching 100g of the stibnite powder for 30min at 50 ℃ by using the mixed solution, and carrying out solid-liquid separation to obtain the Na-containing material₃SbS₃The leachate of (2);

mixing 600mL of the leaching solution with 12.5g of sodium hydroxide in an autoclave, carrying out antimony precipitation reaction at the temperature of 120 ℃ for 3 hours in an oxidizing atmosphere with the oxygen pressure of 0.8MPa, and carrying out solid-liquid separation to obtain the sodium antimonate.

Example 2

The chemical composition of stibnite comprises: SiO 2₂52.81 wt.%, Sb 26.84 wt.%, S9.86 wt.%, fe2.11wt.%, Al 1.71 wt.%, and As 0.88 wt.%.

Crushing stibnite ores, and ball-milling until the granularity is 0.18mm to obtain stibnite powder;

preparing a mixed solution, wherein the concentration of sodium sulfide in the mixed solution is 100g/L, and the concentration of sodium hydroxide is 30 g/L; according to the solid-liquid ratio of 1: 4, leaching 100g of the stibnite powder for 15min at 70 ℃ by using the mixed solution, and carrying out solid-liquid separation to obtain the Na-containing material₃SbS₃The leachate of (2);

mixing 600mL of the leaching solution with 22.0g of sodium hydroxide in an autoclave, carrying out antimony precipitation reaction at 150 ℃ for 4 hours in an oxidizing atmosphere with the oxygen pressure of 1MPa, and carrying out solid-liquid separation to obtain the sodium antimonate.

Example 3

The chemical composition of stibnite comprises: SiO 2₂68.58 wt.%, Sb 15.56 wt.%, S11.96 wt.%, fe4.98wt.%, Al 0.52 wt.% and As 0.28 wt.%.

Crushing stibnite ores, and ball-milling until the granularity is 0.18mm to obtain stibnite powder;

preparing a mixed solution, wherein the concentration of sodium sulfide in the mixed solution is 120g/L, and the concentration of sodium hydroxide is 40 g/L; according to the solid-liquid ratio of 1: 4, leaching 100g of the stibnite powder for 30min at 80 ℃ by using the mixed solution, and carrying out solid-liquid separation to obtain the Na-containing material₃SbS₃The leachate of (2);

mixing 600mL of the leaching solution with 40mL of 280g/L sodium hydroxide in an autoclave, carrying out antimony precipitation reaction at 140 ℃ for 2.5h in an oxidizing atmosphere with the oxygen pressure of 1.2MPa, and carrying out solid-liquid separation to obtain the sodium antimonate.

Example 4

The chemical composition of stibnite comprises: SiO 2₂40.77 wt.%, Sb 35.66 wt.%, S17.12 wt.%, Fe 3.75 wt.%, Al 0.84 wt.% and As 0.53 wt.%.

Crushing stibnite ores, and ball-milling until the granularity is 0.18mm to obtain stibnite powder;

preparing a mixed solution, wherein the concentration of sodium sulfide in the mixed solution is 120g/L, and the concentration of sodium hydroxide is 20 g/L; according to the solid-liquid ratio of 1: 5, leaching 100g of the stibnite powder for 45min at 90 ℃ by using the mixed solution, and carrying out solid-liquid separationAfter separation, Na is obtained₃SbS₃The leachate of (2);

mixing 600mL of the leaching solution with 27.0g of sodium hydroxide in an autoclave, carrying out antimony precipitation reaction at 150 ℃ for 4 hours in an oxidizing atmosphere with the oxygen pressure of 1MPa, and carrying out solid-liquid separation to obtain the sodium antimonate.

Carrying out component detection on the sodium antimonate product obtained by the reaction of the leaching solution and the antimony precipitation in the embodiment 1-4 by using an atomic absorption spectrometer, an atomic emission spectrometer, an X fluorescence spectrometer and an X-ray diffractometer, and carrying out whiteness test on the obtained sodium antimonate product by using a whiteness meter; the test results obtained are shown in Table 1.

TABLE 1 leachate and antimony precipitation reaction product composition test results

	Example 1	Example 2	Example 3	Example 4
					Extract rate/%)	96.31	97.22	98.78	99.56
Antimony deposition rate/%)	95.87	98.45	98.84	99.32
					Yield of sodium antimonate/g	23.31	34.78	24.91	25.78
Antimony content/% of sodium antimonate	48.68	51.33	49.8	53.4
					Content of trivalent antimony in sodium antimonate/%)	0.13	0.18	0.09	0.05
Whiteness/%	94	96	85	93

As can be seen from Table 1, by adopting the method provided by the invention, the leaching rate of antimony reaches 96.31-99.56%, the antimony precipitation rate reaches 95.87-99.32%, the content of trivalent antimony is only 0.05-0.18%, and Sb carried in the precipitate is Sb³⁺The Sb content is controlled in a lower range, and the sodium antimonate product has higher Sb resource recovery rate and higher quality; the whiteness reaches 85-96%, and the whiteness is high, which indicates that the obtained sodium antimonate product has excellent quality.

In conclusion, the method combines a sodium sulfide and sodium hydroxide system, realizes selective leaching of antimony and thorough separation of antimony, and prepares the sodium antimonate product by performing oxygen pressure antimony precipitation on the leaching solution, so that the method is low in cost, environment-friendly, suitable for industrialization and high in industrial application and economic value.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.