Novel low-grade bauxite desilicication method

Abstract

The invention provides a novel low-grade bauxite desiliconization method which comprises the following steps: adding isometric raw ore pulp into a plurality of beakers for full reaction to obtain a first reaction solution; adding barium hydroxide solids with different masses into the first reaction solution, setting different reaction temperatures and reaction time, and filtering after reaction to obtain silicide-containing powder precipitate and a second reaction solution; introducing carbon dioxide gas into the obtained second reaction solution, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; and adding a 30% hydrochloric acid solution into the filtered third reaction solution, carrying out acid dissolution, and diluting to obtain pre-desiliconized bauxite slurry. According to the novel low-grade bauxite desilicication method, the aluminum-silicon ratio of the bauxite is increased, the aluminum-silicon ratio of the bauxite slurry prepared through the method is high, the loss of the aluminum element content is extremely small, and the quality of a subsequently obtained product can be greatly improved.

Description

Technical Field

[0001] The invention relates to the field of metallurgy, and in particular to a novel method for desiliconizing low-grade bauxite. Background Art

[0002] Bauxite is the main raw material for the production of primary aluminum. The essence of the entire production chain of the aluminum industry is to achieve the entire process of conversion from mining - bauxite - alumina - electrolytic aluminum - primary aluminum products to deep aluminum processing according to the needs of the product terminal. Bauxite resources play a decisive role in the construction and development of the aluminum industry. Figure 1 As shown, Guangxi is rich in bauxite resources, has good resource endowment, and has good geological conditions for bauxite mineralization. It is one of the four provinces with the largest bauxite reserves in the country and occupies an important position in the country. According to the results of mineral resource surveys, as of the end of 2021, the total amount of bauxite resources in Guangxi has been identified to be approximately 855 million tons, accounting for more than 25% of the country's bauxite resources, of which more than 90% are accumulation-type bauxite and less than 10% are sedimentary bauxite. Summary of the invention

[0003] The purpose of the present invention is to provide a novel method for desiliconizing low-grade bauxite, thereby improving its aluminum-silicon ratio. The bauxite slurry prepared by the present invention has a high aluminum-silicon ratio and very little loss of aluminum content, which can greatly improve the quality of subsequent products.

[0004] To achieve the above object, the present invention provides a novel low-grade bauxite desiliconization method, comprising the following steps: S1. Add equal volumes of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding different masses of barium hydroxide solid to the first reaction solution, setting different reaction temperatures and reaction times, and filtering after the reaction to obtain a silicide-containing powder precipitate and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to obtain the pre-desiliconized bauxite slurry.

[0005] Preferably, the ratio of raw ore slurry to solid barium hydroxide is 100 mL / 2-3 g.

[0006] Preferably, in S2, the reaction time is 30-50 min and the reaction temperature is 25-90°C.

[0007] Preferably, in S3, the carbon dioxide gas is introduced for 30-40 minutes.

[0008] Preferably, in S3, the drying temperature is 60-70°C and the drying time is 30-40 minutes.

[0009] Preferably, in S4, the ratio of 30% hydrochloric acid solution to raw ore pulp is 1:2 Preferably, in S4, the dilution ratio is 2:1.

[0010] Therefore, the present invention adopts the above-mentioned novel low-grade bauxite desiliconization method, and its technical effects are as follows: (1) By adding barium hydroxide to low-grade bauxite slurry, the silicon element in the original slurry is converted into barium silicate, and then filtered to remove the silicon element, obtaining a slurry solution with extremely low silicon content and less aluminum loss. The addition of barium hydroxide significantly increases the aluminum-silicon ratio of the bauxite slurry, reduces the loss of aluminum in the desiliconization process, and allows it to be used for subsequent aluminum metal refining.

[0011] (2) The preparation process of the present invention is simple and efficient, and the price of barium hydroxide is relatively low, which can reduce production costs, improve production efficiency, and easily realize industrial production. It has great application prospects in the field of bauxite slurry refining. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a line chart of desiliconization rate. DETAILED DESCRIPTION

[0013] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0014] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0015] Example 1 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 2 g of solid barium hydroxide to the first reaction solution, keeping the mixture at room temperature for 30 min, and filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0016] Example 2 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 2 g of solid barium hydroxide to the first reaction solution, keeping the mixture at room temperature for 40 min, and filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0017] Example 3 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 2 g of solid barium hydroxide to the first reaction solution, keeping the mixture at room temperature for 50 min, and filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0018] Example 4 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 3 g of solid barium hydroxide to the first reaction solution, keeping the mixture at room temperature for 30 min, and filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0019] Example 5 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 3 g of solid barium hydroxide to the first reaction solution, keeping the mixture at room temperature for 40 min, and filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0020] Example 6 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 3 g of solid barium hydroxide to the first reaction solution, keeping the mixture at room temperature for 50 min, and filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0021] Example 7 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 3 g of solid barium hydroxide to the first reaction solution, keeping the mixture at room temperature for 30 min, filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0022] Example 8 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 3 g of solid barium hydroxide to the first reaction solution, keeping the temperature at 50° C. for 30 min, filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0023] Example 9 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 3 g of solid barium hydroxide to the first reaction solution, keeping the temperature at 60° C. for 30 min, filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0024] Example 10 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 3 g of solid barium hydroxide to the first reaction solution, keeping the temperature at 70° C. for 30 min, filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0025] Embodiment 11 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 3 g of solid barium hydroxide to the first reaction solution, keeping the temperature at 80° C. for 30 min, filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0026] Example 12 A novel method for desiliconizing low-grade bauxite comprises the following steps: S1. Add 100 mL of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding 3 g of solid barium hydroxide to the first reaction solution, keeping the temperature at 90° C. for 30 min, filtering after the reaction to obtain a powder precipitate containing silicide and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2 for 30 minutes, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 50 mL of 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to 250 mL to obtain a pre-desiliconized bauxite slurry.

[0027] Measurement results The solid powder obtained after evaporation of 100 mL of the original ore pulp was 99.65 g. The mass fraction of SiO2 in the original ore pulp and the content of SiO2 in the solution after each acid dissolution were obtained by semi-quantitative analysis. The results are shown in Table 1 and Figure 1 shown.

[0028] Desiliconization rate calculated based on mass The mass of SiO2 in the original slurry: 99.65×10.29%=10.253g The mass of SiO2 in Example 1: 1.321×0.25=0.33025g The mass of SiO2 in Example 2: 1.281×0.25=0.32025g The mass of SiO2 in Example 3: 1.177×0.25=0.29425g The mass of SiO2 in Example 4: 1.148×0.25=0.28700g The mass of SiO2 in Example 5: 1.223×0.25=0.30575g The mass of SiO2 in Example 6: 1.010×0.25=0.25250g The mass of SiO2 in Example 7: 1.252×0.25=0.31300g The mass of SiO2 in Example 8: 1.350×0.25=0.33750g The mass of SiO2 in Example 9: 1.384×0.25=0.34600g The mass of SiO2 in Example 10: 1.269×0.25=0.31725g The mass of SiO2 in Example 11: 1.459×0.25=0.36475 g The mass of SiO2 in Example 12: 1.471×0.25=0.36775 The desiliconization rate is obtained: Example 1 Desiliconization rate: (10.253-0.33025) / 10.253×100%=96.77% Example 2 Desiliconization rate: (10.253-0.32025) / 10.253×100%=96.87% Example 3 Desiliconization rate: (10.253-0.29425) / 10.253×100%=97.13% Example 4 Desiliconization rate: (10.253-0.28700) / 10.253×100%=97.30% Example 5 Desiliconization rate: (10.253-0.30575) / 10.253×100%=97.02% Example 6 Desiliconization rate: (10.253-0.25250) / 10.253×100%=97.53% Example 7 Desiliconization rate: (10.253-0.31300) / 10.253×100%=96.94% Example 8 Desiliconization rate: (10.253-0.33750) / 10.253×100%=96.70% Example 9 Desiliconization rate: (10.253-0.34600) / 10.253×100%=96.62% Example 10 Desiliconization rate: (10.253-0.31725) / 10.253×100%=96.91% Example 11 Desiliconization rate: (10.253-0.36475) / 10.253×100%=96.44% Example 12 Desiliconization rate: (10.253-0.36775) / 10.253×100%=96.41% Table 1 Semi-quantitative analysis results:

[0029] Therefore, the present invention adopts the above-mentioned new method for desiliconizing low-grade bauxite to improve its aluminum-silicon ratio. The bauxite slurry prepared by the present invention has a high aluminum-silicon ratio and very little loss of aluminum content, which can greatly improve the quality of subsequent products.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A novel low-grade bauxite desiliconization method, characterized in that: The steps include: S1. Add equal volumes of raw ore slurry into multiple beakers for full reaction to obtain a first reaction solution; S2, adding different masses of barium hydroxide solid to the first reaction solution, setting different reaction temperatures and reaction times, and filtering after the reaction to obtain a silicide-containing powder precipitate and a second reaction solution; S3, passing carbon dioxide gas into the second reaction solution obtained in step S2, filtering and drying to obtain aluminum hydroxide powder and a third reaction solution; S4. Add 30% hydrochloric acid solution to the third reaction solution filtered in step S3, dissolve it in acid, and dilute it to obtain the pre-desiliconized bauxite slurry.

2. A novel low-grade bauxite desiliconization method according to claim 1, characterized in that: The ratio of the raw ore slurry to the solid barium hydroxide is 100 mL / 2-3 g.

3. A novel low-grade bauxite desiliconization method according to claim 1, characterized in that: In S2, the reaction time is 30-50 min, and the reaction temperature is 25-90°C.

4. A novel low-grade bauxite desiliconization method according to claim 1, characterized in that: In S3, the carbon dioxide gas is introduced for 30-40 minutes.

5. A novel low-grade bauxite desiliconization method according to claim 1, characterized in that: In S3, the drying temperature is 60-70°C and the drying time is 30-40 minutes.

6. A novel low-grade bauxite desiliconization method according to claim 1, characterized in that: In S4, the ratio of 30% hydrochloric acid solution to raw ore pulp is 1:

2.

7. A novel low-grade bauxite desiliconization method according to claim 1, characterized in that: In S4, the dilution ratio was 2:1.

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