Desiliconization method of celestite ore

Abstract

The invention belongs to the technical field of ore processing treatment, and particularly relates to a celestite ore deep desilicication method which comprises the following steps: S1, ore grinding operation: grinding celestite ore, and sieving to obtain celestite powder; s2, desiliconization operation: adding a hydrochloric acid solution and ammonium fluoride into the celestite powder, and carrying out desiliconization, first filtering, first washing and first drying to obtain desiliconized celestite powder; s3, alkali washing operation: adding a sodium hydroxide solution into the desiliconized celestite powder, and carrying out alkali washing, second filtering, second washing and second drying to obtain alkali-washed celestite powder; and S4, pickling operation: adding a sulfuric acid solution into the alkali-washed celestite powder, and carrying out pickling, third filtering, third washing and third drying to obtain refined celestite powder. According to the deep desilicication method for the celestite ore, silicon can be effectively removed under the condition that the low loss rate of strontium is ensured only through the low reaction temperature.

Description

Technical Field

[0001] The present application belongs to the technical field of ore processing and treatment, and specifically relates to a deep desiliconization method for celestite ore. Background Art

[0002] The main component of celestine ore is strontium sulfate, which is one of the important mineral resources. It has been widely used in electronics, medicine, military industry and optics. However, with the continuous mining of celestine ore, the hybridization of gangue has become more and more serious, and the grade of celestine has been seriously affected. After being treated by flotation or reverse flotation, celestine still contains some impurities, mainly including carbonates, metal oxides, silicon dioxide and other silicon-based compounds; among them, silicon-containing impurities account for a large proportion and are not easy to remove. Although the silicon content in celestine concentrates from different origins fluctuates slightly, it is still relatively high and even accounts for the largest proportion. The existing pretreatment process can effectively treat carbonates and metal oxides in celestine ore, but it is not effective in removing silicon dioxide and other silicon compounds. At present, the conventional desiliconization method in the strontium salt industry is flotation or reverse flotation. This method is suitable for celestine ore with a high silicon content, and the grade of the treated concentrate is about 80% to 90%, of which silicon dioxide and other silicon-based compounds account for about 3% to 5%.

[0003] In the crude strontium carbonate prepared by a single double decomposition using the existing process, silicon compounds remain in the form of acid-insoluble substances, and it is necessary to dissolve in acid and then double decompose again to obtain high-purity strontium carbonate. The double decomposition to prepare strontium carbonate has high requirements on the purity of the raw material celestite.

[0004] Therefore, a new method for desiliconization of celestite ore is needed to achieve effective desiliconization of celestite ore with a simple and convenient process flow. Summary of the invention

[0005] The problem that the present application aims to solve is to provide a method for desiliconization of celestite ore, which only requires a relatively low reaction temperature to achieve effective removal of silicon while ensuring a low loss rate of strontium.

[0006] In order to solve the above problems, this application adopts the following technical solutions:

[0007] The present application provides a desiliconization method for celestite ore, comprising the following steps:

[0008] S1. Grinding operation: grinding the celestite ore and sieving it to obtain celestite powder;

[0009] S2, desiliconization operation: adding hydrochloric acid solution and ammonium fluoride to the celestite powder, performing desiliconization, first filtering, first washing and first drying to obtain desiliconized celestite powder;

[0010] S3, alkali washing operation: adding sodium hydroxide solution to the desiliconized celestite powder, performing alkali washing, second filtration, second washing and second drying to obtain alkali washed celestite powder;

[0011] S4, acid washing operation: adding sulfuric acid solution to the alkali-washed celestite powder, performing acid washing, third filtration, third washing and third drying to obtain refined celestite powder.

[0012] Furthermore, the particle size of the celestite powder is 40 to 75 μm.

[0013] Furthermore, the concentration of the hydrochloric acid solution is 15-22 wt%.

[0014] Furthermore, the concentration of the sodium hydroxide solution is 20-30wt%.

[0015] Furthermore, the concentration of the sulfuric acid solution is 35-45wt%.

[0016] Furthermore, the solid-to-liquid ratio (g / mL / mL / mL) of the celestite powder, the hydrochloric acid solution, the sodium hydroxide solution and the sulfuric acid solution is 1:(1.5-2.5):(0.8-1.4):(2-3).

[0017] Furthermore, the weight ratio of the celestite powder to the ammonium fluoride is 1:(0.20-0.6).

[0018] Furthermore, the desiliconization temperature is 70 to 80° C., and the desiliconization time is 50 to 60 minutes.

[0019] Furthermore, the temperature of the alkali washing is 60-75° C., and the time of the alkali washing is 50-60 minutes.

[0020] Furthermore, the pickling temperature is 60-75° C., and the pickling time is 50-60 min.

[0021] This application has the following beneficial effects:

[0022] (1) The desiliconization method of celestite ore provided in the present application has a desiliconization rate higher than 97.5%, which can effectively remove the silicon element in the celestite ore and ensure low loss of effective components during the desiliconization process, with a strontium loss rate below 1.7%.

[0023] (2) The desiliconization method of celestite ore provided in the present application has simple steps, involves readily available raw materials, does not require high-temperature roasting, has a short reaction time, can reduce the preparation cost and preparation time of high-purity strontium carbonate, and is suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1The present invention is a schematic flow diagram of a desiliconization method for celestite ore. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0026] Example 1

[0027] Three celestite ores from a mine in Sichuan were randomly selected as samples, and the silicon and strontium content in the samples were analyzed by XRF. The analysis results are shown in Table 1. XRF detection process: 500g of three samples were taken respectively, ground and passed through a 200-mesh sieve, the powder under the sieve was collected, and the tablets were placed in the detection room of the detection equipment (Japan Rigaku ZSX PrimusIII+ X-ray fluorescence spectrometer), and the detection tube voltage was set to 50KV and the tube current was set to 60mA. After the detection was completed, the samples were recovered. The element content detection in the subsequent embodiments is the same.

[0028] Table 1

[0029]

[0030] Example 2

[0031] Prepare refined lapis lazuli powder by following the steps below:

[0032] S1, grinding operation: select the celestine ore of sample 1 in Example 1, grind it and pass it through a 400-mesh sieve, collect the powder in the sieve and pass it through a 200-mesh sieve, collect the sieved powder, and obtain celestine powder with a particle size of 40 to 75 μm;

[0033] S2, desiliconization operation: after adding 20 mL of 15 wt% hydrochloric acid to 10 g of the celestine powder, add 6 g of ammonium fluoride solid and stir until dissolved, desiliconize at 80° C. for 60 min, filter, wash three times with deionized water and dry to obtain desiliconized celestine powder;

[0034] S3, alkali washing operation: adding 10 mL of a 20 wt% sodium hydroxide solution to the desiliconized celestite powder, alkali washing at 60° C. for 50 min, filtering, washing three times with deionized water and drying to obtain an alkali-washed celestite powder;

[0035] S4, pickling operation: add 30 mL of 45 wt% sulfuric acid solution to the alkali-washed celestite powder, carry out pickling at 60° C. for 50 min, filter, wash three times with deionized water and dry to obtain 9.71 g of refined celestite powder.

[0036] Example 3

[0037] Prepare refined lapis lazuli powder by following the steps below:

[0038] S1, grinding operation: select the celestine ore of sample 2 in Example 1, grind it and pass it through a 400-mesh sieve, collect the powder in the sieve and pass it through a 200-mesh sieve, collect the sieved powder, and obtain celestine powder with a particle size of 40 to 75 μm;

[0039] S2, desiliconization operation: after adding 25mL of 22wt% hydrochloric acid to 10g of the celestine powder, add 2g of ammonium fluoride solid and stir until dissolved, desiliconize at 70°C for 50min, filter, wash three times with deionized water and dry to obtain desiliconized celestine powder;

[0040] S3, alkali washing operation: adding 8 mL of a 30 wt% sodium hydroxide solution to the desiliconized celestite powder, alkali washing at 60° C. for 55 min, filtering, washing three times with deionized water and drying to obtain an alkali-washed celestite powder;

[0041] S4, pickling operation: add 20 mL of 35 wt % sulfuric acid solution to the alkali-washed celestite powder, perform pickling at 75° C. for 55 min, filter, wash three times with deionized water and dry to obtain 9.82 g of refined celestite powder.

[0042] Example 4

[0043] Prepare refined lapis lazuli powder by following the steps below:

[0044] S1, grinding operation: select the celestine ore of sample 3 in Example 1, grind it and pass it through a 400-mesh sieve, collect the powder in the sieve and pass it through a 200-mesh sieve, collect the sieved powder, and obtain celestine powder with a particle size of 40 to 75 μm;

[0045] S2, desiliconization operation: after adding 45mL of 18.5wt% hydrochloric acid to 30g of the celestine powder, add 12g of ammonium fluoride solid and stir until dissolved, desiliconize at 80°C for 55min, filter, wash three times with deionized water and dry to obtain desiliconized celestine powder;

[0046] S3, alkali washing operation: adding 42 mL of a 25 wt% sodium hydroxide solution to the desiliconized celestite powder, alkali washing was performed at 75° C. for 60 min, and then filtering, washing three times with deionized water, and drying to obtain an alkali-washed celestite powder;

[0047] S4, pickling operation: add 80 mL of 40 wt % sulfuric acid solution to the alkali-washed celestite powder, perform pickling at 60° C. for 60 min, filter, wash three times with deionized water and dry to obtain 28.97 g of refined celestite powder.

[0048] Comparative Example 1

[0049] Prepare refined lapis lazuli powder by following the steps below:

[0050] S1, grinding operation: grinding the celestite ore of sample 1 in Example 1, passing through a 400-mesh sieve, collecting the powder in the sieve and passing through a 200-mesh sieve, collecting the sieved powder, and obtaining celestite powder with a particle size of 40 to 75 μm;

[0051] S2, desiliconization operation: after adding 20 mL of 15 wt% hydrochloric acid to 10 g of the celestine powder, add 6 g of ammonium fluoride solid and stir until dissolved, desiliconize at 80° C. for 60 min, filter, wash three times with deionized water and dry to obtain desiliconized celestine powder;

[0052] S3, alkali washing operation: adding 10 mL of a 20 wt% sodium hydroxide solution to the desiliconized celestite powder, alkali washing at 60° C. for 50 min, filtering, washing three times with deionized water and drying to obtain an alkali-washed celestite powder;

[0053] S4, acid washing operation: add 30 mL of 15 wt% sulfuric acid solution to the alkali-washed celestite powder, keep it at 60° C. for 50 min, then filter it, wash it three times with deionized water and dry it to obtain 9.87 g of refined celestite powder.

[0054] Comparative Example 2

[0055] Prepare refined lapis lazuli powder by following the steps below:

[0056] S1, grinding operation: grinding the celestite ore of sample 1 in Example 1, passing through a 400-mesh sieve, collecting the powder in the sieve and passing through a 200-mesh sieve, collecting the sieved powder, and obtaining celestite powder with a particle size of 40 to 75 μm;

[0057] S2, desiliconization operation: after adding 20 mL of 15 wt% hydrochloric acid to 10 g of the celestine powder, add 6 g of ammonium fluoride solid and stir until dissolved, desiliconize at 80° C. for 60 min, filter, wash three times with deionized water and dry to obtain desiliconized celestine powder;

[0058] S3, alkali washing operation: adding 10 mL of 6 wt% sodium hydroxide solution to the desiliconized celestite powder, alkali washing at 60° C. for 50 min, filtering, washing three times with deionized water and drying to obtain alkali-washed celestite powder;

[0059] S4, pickling operation: add 30 mL of 45 wt% sulfuric acid solution to the alkali-washed celestite powder, perform pickling at 60° C. for 50 min, filter, wash three times with deionized water and dry to obtain 9.74 g of refined celestite powder.

[0060] Comparative Example 3

[0061] Prepare refined lapis lazuli powder by following the steps below:

[0062] S1, grinding operation: grinding the celestite ore of sample 1 in Example 1, passing through a 400-mesh sieve, collecting the powder in the sieve and passing through a 200-mesh sieve, collecting the sieved powder, and obtaining celestite powder with a particle size of 40 to 75 μm;

[0063] S2, desiliconization operation: after adding 20 mL of 15 wt% hydrochloric acid to 10 g of the celestine powder, add 6 g of ammonium fluoride solid and stir until dissolved, desiliconize at 80° C. for 60 min, filter, wash three times with deionized water and dry to obtain desiliconized celestine powder;

[0064] S3, alkali washing operation: add 20 mL of 24 wt% ammonia solution to the desiliconized celestite powder, perform alkali washing at 60° C. for 50 min, filter, wash three times with deionized water and dry to obtain alkali washed celestite powder;

[0065] S4, pickling operation: add 30 mL of 45 wt% sulfuric acid solution to the alkali-washed celestite powder, perform pickling at 60° C. for 50 min, filter, wash three times with deionized water and dry to obtain 9.72 g of refined celestite powder.

[0066] Comparative Example 4

[0067] Prepare refined lapis lazuli powder by following the steps below:

[0068] S1, grinding operation: grinding the celestite ore of sample 1 in Example 1, passing through a 400-mesh sieve, collecting the powder in the sieve and passing through a 200-mesh sieve, collecting the sieved powder, and obtaining celestite powder with a particle size of 40 to 75 μm;

[0069] S2, desiliconization operation: after adding 20 mL of 15 wt% hydrochloric acid to 10 g of the celestine powder, add 6 g of ammonium fluoride solid and stir until dissolved, desiliconize at 80° C. for 60 min, filter, wash three times with deionized water and dry to obtain desiliconized celestine powder;

[0070] S3, alkali washing operation: adding 10 mL of a 20 wt% sodium hydroxide solution to the desiliconized celestite powder, alkali washing at 60° C. for 50 min, filtering, washing three times with deionized water and drying to obtain an alkali-washed celestite powder;

[0071] S4, acid washing operation: add 30 mL of 36 wt% hydrochloric acid solution to the alkali-washed celestite powder, keep it at 60° C. for 50 min, then filter it, wash it three times with deionized water and dry it to obtain 7.18 g of refined celestite powder.

[0072] Experimental Example 1 Verification of silicon removal effect

[0073] The refined celestite powder obtained in Examples 2 to 4 and Comparative Examples 1 to 4 was analyzed by the XRF detection method described in Example 1 to obtain the final silicon content and the final strontium content, and the desiliconization rate and the strontium loss rate were calculated. Then, 5 g of the refined celestite powder obtained in Examples 2 to 4 or Comparative Examples 1 to 4 was weighed to prepare strontium carbonate, 4.3 g of ammonium carbonate solid (excess ammonium carbonate) was added, and 15 mL of deionized water was added. The mixture was reacted at 75° C. for 120 min, and then filtered. The mixture was washed three times with hot water and dried to obtain strontium carbonate powder. The strontium carbonate content was detected by referring to the detection method in "HG / T 4508-2013 High-purity Strontium Carbonate", and the conversion rate when preparing strontium carbonate was calculated.

[0074] Desiliconization rate (%) = (m 原料 ×Wt 硅原料 -m 精制粉末 ×Wt 硅精制粉末 ) / m 原料 ×Wt 硅原料

[0075] Strontium loss rate (%) = (m 原料 ×Wt SrO原料 -m 精制粉末 ×Wt SrO精制粉末 ) / m 原料 ×Wt SrO原料

[0076] Carbonation conversion rate: =m 实际碳酸锶 / m 理论碳酸锶 (m 理论碳酸锶 It can be calculated from the chemical reaction formula SrSO4+CO2-3=SrCO3+SO2-4. )

[0077] Table 2

[0078]

[0079] The results show that the desiliconization method of celestite ore provided in this application can achieve a desiliconization rate of more than 97.5%, and can control the strontium loss rate below 1.7% during desiliconization, and can effectively control the residual fluorine element, and can ensure that the desiliconized celestite has a conversion rate of more than 90% in the subsequent preparation of strontium carbonate. It is a celestite desiliconization method with great industrial value.

[0080] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A method for desiliconization of celestite ore, characterized in that: The following steps are involved: S1. Grinding operation: grinding the celestite ore and sieving it to obtain celestite powder; S2, desiliconization operation: adding hydrochloric acid solution and ammonium fluoride to the celestite powder, performing desiliconization, first filtering, first washing and first drying to obtain desiliconized celestite powder; S3, alkali washing operation: adding sodium hydroxide solution to the desiliconized celestite powder, performing alkali washing, second filtration, second washing and second drying to obtain alkali washed celestite powder; S4, acid washing operation: adding sulfuric acid solution to the alkali-washed celestite powder, performing acid washing, third filtration, third washing and third drying to obtain refined celestite powder.

2. The desiliconization method according to claim 1, characterized in that: The particle size of the celestite powder is 40 to 75 μm.

3. The desiliconization method according to claim 1, characterized in that: The concentration of the hydrochloric acid solution is 15-22 wt %.

4. The desiliconization method according to claim 1, characterized in that: The concentration of the sodium hydroxide solution is 20-30 wt %.

5. The desiliconization method according to claim 1, characterized in that: The concentration of the sulfuric acid solution is 35-45 wt %.

6. The desiliconization method according to claim 1, characterized in that: The solid-to-liquid ratio (g / mL / mL / mL) of the celestite powder, the hydrochloric acid solution, the sodium hydroxide solution and the sulfuric acid solution is 1:(1.5-2.5):(0.8-1.4):(2-3).

7. The desiliconization method according to claim 1, characterized in that: The weight ratio of the celestite powder to the ammonium fluoride is 1:(0.20-0.6).

8. The desiliconization method according to claim 1, characterized in that: The desiliconization temperature is 70-80° C., and the desiliconization time is 50-60 minutes.

9. The desiliconization method according to claim 1, characterized in that: The temperature of the alkali washing is 60-75° C., and the time of the alkali washing is 50-60 minutes.

10. The desiliconization method according to claim 1, characterized in that: The pickling temperature is 60-75° C., and the pickling time is 50-60 min.

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