Method for separating lithium and silicon from lithium-containing porcelain clay ore

Abstract

The invention discloses a method for separating lithium and silicon from lithium-containing china clay ore, and belongs to the technical field of inorganic separation and extraction.The method comprises the steps that the lithium-containing china clay ore is roasted and soaked in water to obtain a lithium-containing solution, separated filter residues are subjected to acid leaching to obtain the lithium-containing solution and a silicon-containing solid, and then the lithium-containing solid and the silicon-containing solid are separated; the method provided by the invention realizes graded extraction and separation, one-time roasting and two-time leaching of main elements lithium and silicon in the lithium-containing porcelain clay ore, improves the leaching rate of lithium, has the advantages of large treatment capacity and simple process, can realize effective separation and extraction of lithium and silicon as leaching residues are silicon-containing solids, has the advantages of low cost, easy operation and high efficiency, and is suitable for industrial production. The comprehensive utilization value of the lithium-containing porcelain clay ore is improved, and the method has remarkable economic benefits.

Description

Technical Field

[0001] The invention relates to a method for separating lithium and silicon from lithium-containing porcelain clay ore, belonging to the technical field of inorganic separation and extraction. Background Art

[0002] With the promotion of new energy vehicles, the demand for lithium has increased year by year. Lithium resources are facing the problem of sustainable supply. The development and utilization of lithium resources has become a research hotspot and industry focus at this stage.

[0003] At present, the world's natural lithium resources mainly include salt lake brine, hard rock minerals and clay minerals. At present, the lithium resources that are mined more are salt lake brine and lithium-containing minerals. The mainstream raw materials for lithium extraction in my country are spodumene, lepidolite and clay lithium ore, but in the future, it is inevitable that the lithium grade will be reduced and the resources will be exhausted. It is very important to develop low-grade lithium ore extraction technology.

[0004] Lithium kaolin is a lithium-containing ore, but its chemical composition and organizational structure are very different from spodumene and clay lithium ore. Compared with spodumene, lithium kaolin has a lower lithium content, with a Li2O content of 1.2-2.0%, and a more complex organizational structure. The extraction of lithium kaolin is still difficult and requires a specific process solution.

[0005] ZL201811090605.9 discloses a method for directly extracting lithium from lithium porcelain stone ore by roasting-water leaching. The roasting auxiliary materials used in this method are potassium sulfate, calcium sulfate or calcium carbonate, but the recovery rate of lithium is between 85-90%. ZL202111213385.6 discloses a method for extracting lithium from lithium porcelain stone raw materials. This method adopts the method of roasting-acid leaching. The auxiliary materials used in the roasting process are potassium sulfate, calcium sulfate or calcium carbonate, but this method produces a large amount of calcium silicon waste residue, which is difficult to handle. CN117425740A discloses a method for extracting lithium aluminum from red mud in cooperation with lithium porcelain stone. The recovery rate of lithium in this method can reach 98.7%, but it needs to be roasted twice, and the roasting temperature is high. Therefore, it is necessary to find an efficient, simple, and short-range lithium extraction method to ensure the low cost and stable supply of lithium. Summary of the invention

[0006] In view of this, the present invention provides a method for separating lithium and silicon from lithium-containing china clay ore, by roasting and leaching the lithium-containing china clay ore to obtain a lithium-containing solution, and then acid-leaching the separated filter residue to obtain a lithium-containing solution and a silicon-containing solid, thereby achieving effective separation of lithium and silicon in the lithium-containing china clay ore.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A method for separating lithium and silicon from lithium-containing china clay ore, comprising the following steps:

[0009] S1, crushing the lithium-containing china clay ore and mixing it with sodium hydroxide to obtain a mixture;

[0010] S2, roasting the mixed material to obtain a roasted material;

[0011] S3, mixing the roasted material with water for leaching, and performing solid-liquid separation after the leaching is completed to obtain a first filtrate and a filter residue;

[0012] S4, acid leaching the filter residue, and after the acid leaching, solid-liquid separation is performed to obtain a second filtrate and silicon-containing solids, and the first filtrate and the second filtrate are combined to obtain a lithium-containing solution.

[0013] On the basis of the above technical solution, the present invention further defines the solution as follows:

[0014] Furthermore, the particle size of the crushed material in step S1 is 40-200 mesh.

[0015] Furthermore, the mass ratio of the lithium-containing china clay ore to the sodium hydroxide is 4:1-1:4.

[0016] Furthermore, in step S2, the calcination temperature is 300-1500° C. and the calcination time is 10-240 min.

[0017] Furthermore, in step S3, the temperature of the water mixed leaching is 20-95° C., and the time is greater than 5 minutes.

[0018] Further, the leaching is carried out under stirring conditions.

[0019] Furthermore, in step S4, the acid leaching is carried out with sulfuric acid, and the concentration of the sulfuric acid is 0.5-2.0 mol / L.

[0020] Furthermore, in step S4, the acid leaching temperature is 20-95° C. and the time is greater than 5 minutes.

[0021] Furthermore, the acid leaching is carried out under stirring conditions.

[0022] The beneficial effects of the present invention are:

[0023] The method of the present invention realizes the graded extraction and separation of lithium and silicon, the main elements in lithium-containing porcelain clay ore, and performs roasting once and leaching twice, thereby improving the leaching rate of lithium, having a large processing capacity and a simple process. The leached residue is a silicon-containing solid, which can realize the effective separation and extraction of lithium and silicon. The method has the advantages of low cost, easy operation and high efficiency, thereby improving the comprehensive utilization value of lithium-containing porcelain clay ore and having significant economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Example 1

[0027] A method for separating lithium and silicon from lithium-containing china clay ore, comprising the following steps:

[0028] S1: crushing and screening the lithium-containing china clay ore to obtain 100-mesh lithium-containing china clay ore powder;

[0029] S2: mixing the lithium-containing china clay ore and sodium hydroxide in a mass ratio of 10:5 to obtain a mixture;

[0030] S3: calcining the mixed material at 400° C. to obtain a calcined material;

[0031] S4: leaching the roasted material in water, adding 100 g of pure water, the leaching temperature is 85° C., the leaching time is 15 minutes, and the first filtrate and filter residue are obtained;

[0032] S5: acid leaching the filter residue, adding 100 g of 1.5 mol / L sulfuric acid, leaching temperature 85° C., leaching time 15 minutes, obtaining a second filtrate and silicon-containing solids, combining the first filtrate and the second filtrate to obtain a lithium-containing solution, measuring the lithium content, and calculating the lithium recovery rate to be 73.96%.

[0033] Example 2

[0034] A method for separating lithium and silicon from lithium-containing china clay ore, comprising the following steps:

[0035] S1: crushing and screening the lithium-containing china clay ore to obtain 100-mesh lithium-containing china clay ore powder;

[0036] S2: mixing the lithium-containing china clay ore and sodium hydroxide in a mass ratio of 10:10 to obtain a mixture;

[0037] S3: calcining the mixed material at 700° C. to obtain a calcined material;

[0038] S4: leaching the roasted material in water, adding 100 g of pure water, the leaching temperature is 85° C., the leaching time is 15 minutes, and the first filtrate and filter residue are obtained;

[0039] S5: acid leaching the filter residue, adding 100 g of 1.5 mol / L sulfuric acid, leaching temperature 85° C., leaching time 15 minutes, obtaining a second filtrate and silicon-containing solids, combining the first filtrate and the second filtrate to obtain a lithium-containing solution, measuring the lithium content, and calculating the lithium recovery rate to be 74.15%.

[0040] Example 3

[0041] A method for separating lithium and silicon from lithium-containing china clay ore, comprising the following steps:

[0042] S1: crushing and screening the lithium-containing china clay ore to obtain 100-mesh lithium-containing china clay ore powder;

[0043] S2: mixing the lithium-containing china clay ore and sodium hydroxide in a mass ratio of 10:11 to obtain a mixture;

[0044] S3: calcining the mixed material at 800° C. to obtain a calcined material;

[0045] S4: leaching the roasted material in water, adding 100 g of pure water, the leaching temperature is 85° C., the leaching time is 15 minutes, and the first filtrate and filter residue are obtained;

[0046] S5: acid leaching the filter residue, adding 100g 1.5mol / L sulfuric acid, leaching temperature 85°C, leaching time 15 minutes, obtaining a second filtrate and silicon-containing solids, combining the first filtrate and the second filtrate to obtain a lithium-containing solution, measuring the lithium content, and calculating the lithium recovery rate to be 91.97%.

Claims

1. A method for separating lithium and silicon from lithium-containing china clay ore, characterized in that: Here are the steps: S1, crushing the lithium-containing china clay ore and mixing it with sodium hydroxide to obtain a mixture; S2, roasting the mixed material to obtain a roasted material; S3, mixing the roasted material with water for leaching, and performing solid-liquid separation after the leaching is completed to obtain a first filtrate and a filter residue; S4, acid leaching the filter residue, and after the acid leaching, solid-liquid separation is performed to obtain a second filtrate and silicon-containing solids, and the first filtrate and the second filtrate are combined to obtain a lithium-containing solution.

2. The method for separating lithium and silicon from lithium-containing china clay ore according to claim 1, characterized in that: The particle size of the crushed material in step S1 is 40-200 mesh.

3. The method for separating lithium and silicon from lithium-containing china clay ore according to claim 1 or 2, characterized in that: The mass ratio of the lithium-containing china clay ore to the sodium hydroxide is 4:1-1:

4.

4. The method for separating lithium and silicon from lithium-containing china clay ore according to claim 1, characterized in that: The calcination temperature in step S2 is 300-1500° C. and the calcination time is 10-240 min.

5. The method for separating lithium and silicon from lithium-containing china clay ore according to claim 1, characterized in that: In step S3, the temperature of the water mixed leaching is 20-95° C., and the time is greater than 5 minutes.

6. The method for separating lithium and silicon from lithium-containing china clay ore according to claim 5, characterized in that: The leaching is carried out under stirring conditions.

7. The method for separating lithium and silicon from lithium-containing china clay ore according to claim 1, characterized in that: The acid leaching in step S4 is carried out with sulfuric acid, and the concentration of the sulfuric acid is 0.5-2.0 mol / L.

8. The method for separating lithium and silicon from lithium-containing china clay ore according to claim 1, characterized in that: The acid leaching temperature in step S4 is 20-95° C. and the time is greater than 5 minutes.

9. The method for separating lithium and silicon from lithium-containing china clay ore according to claim 8, characterized in that: The acid leaching is carried out under stirring conditions.

Images