A lithium adsorbent, its preparation method and use

Abstract

The application belongs to the field of adsorbents, and particularly relates to a lithium adsorbent and a preparation method and application thereof. The preparation method of the lithium adsorbent comprises lithium extraction residue treatment, titanium-rich material treatment, silicon powder treatment, adsorbent precursor preparation and adsorbent conversion preparation. In the adsorbent precursor preparation, the lithium adsorbent with excellent adsorption performance is obtained by adopting a specific concentration of hydrochloric acid aqueous solution and a specific volume ratio of filtrate 2 to silicon powder dilute turbidity liquid.

Description

Technical Field

[0001] This invention relates to the field of adsorbents, specifically to a lithium adsorbent, its preparation method, and its application. Background Technology

[0002] Acid leaching residue from clay-type lithium ore is the solid waste remaining after the leaching process. It typically contains large amounts of elements such as silicon and aluminum, existing in the form of oxides, such as silicon dioxide and aluminum oxide. It may also contain incompletely leached lithium, as well as compounds of other associated elements, such as iron, magnesium, calcium, potassium, and sodium.

[0003] The acid leaching residue from clay-type lithium mines is produced in large quantities. If it is dumped haphazardly, it will occupy a significant amount of land resources, leading to a waste of land resources. Harmful substances in the acid leaching residue may seep into the soil, altering its physical and chemical properties, reducing soil fertility, and affecting vegetation growth.

[0004] Existing technologies for the treatment and utilization of acid leaching residue from clay-type lithium ore mainly include comprehensive recycling to recover products such as lithium carbonate and alumina from the residue, and the preparation of building materials. However, these methods suffer from problems such as complex operation, high cost, environmental unfriendliness, and low utilization rate, and cannot fully utilize the components in the acid leaching residue of clay-type lithium ore.

[0005] Lithium adsorbents are materials that selectively adsorb lithium ions. Their working principle is mainly based on mechanisms such as ion exchange, physical adsorption, or chemical adsorption. For example, some adsorbents have specific functional groups on their surface, which can undergo ion exchange reactions with lithium ions in solution. When a lithium-containing solution (such as brine from salt lakes or leaching solutions from clay-type lithium ore) comes into contact with the adsorbent, lithium ions exchange with exchangeable ions on the adsorbent, thus being adsorbed onto the adsorbent and achieving the separation of lithium from other impurity ions.

[0006] Chinese patent application CN118594466A discloses a method for preparing a manganese-based lithium ion sieve adsorbent. It uses refined lithium slag, a high-valent manganese source, and waste molasses as raw materials, and obtains Li after microwave heating reaction and calcination. 1.6 Mn 1.6 O4 adsorbent. This patent uses manganese metal, which is highly toxic.

[0007] Chinese patent application CN118026251A discloses a silicon-doped titanium-based lithium-ion sieve, its preparation method, and its application. The method involves grinding and calcining metatitanic acid and metasilicic acid, mixing them with a lithium source in water to form a slurry, drying, and then sintering to obtain a precursor. This precursor is then activated with hydrochloric acid to obtain the titanium-based lithium-ion sieve. This patent requires two high-temperature calcinations, resulting in high energy consumption and a high titanium dissolution rate.

[0008] Therefore, there is still an urgent need for a method for treating acid slag from clay-type lithium ore and a method for preparing lithium adsorbents that has advantages such as being environmentally friendly, safe, efficient, energy-saving, low-dissolution rate, and low-cost. Summary of the Invention Invention Overview

[0010] To address the aforementioned technical problems, this invention provides a lithium adsorbent, its preparation method, and its application. On one hand, this invention uses acid leaching residue from clay-type lithium ore to prepare the lithium adsorbent, enabling high-value utilization of the residue and reducing environmental pollution, which is beneficial for industrial development. Furthermore, the preparation method of the lithium adsorbent provided by this invention is simple to operate, highly safe, environmentally friendly, energy-efficient, and cost-effective. Moreover, the lithium adsorbent provided by this invention exhibits high saturated Li adsorption capacity, high Li elution rate, and low adsorbent solubility loss, demonstrating excellent performance. On the other hand, this invention has conducted extensive investigations into the various process steps and parameters of the preparation method, ultimately finding that using a dilute silica powder solution with a silica powder content of 0.05wt%-0.40wt% in step (3) and a hydrochloric acid aqueous solution concentration of 15wt%-20wt% in step (4) to prepare the lithium adsorbent results in a significantly higher saturated Li adsorption capacity and lower adsorbent solubility loss, achieving unexpected technical effects. Invention Details

[0012] To address the aforementioned technical problems, the present invention provides the following technical solutions.

[0013] In a first aspect, the present invention provides a method for preparing a lithium adsorbent.

[0014] A method for preparing a lithium adsorbent, comprising:

[0015] (1) Lithium slag treatment: The acid slag of clay-type lithium ore is separated by sorting to obtain mud and titanium-rich material. The mud is dried to obtain silicon powder.

[0016] (2) Titanium-rich material treatment: The titanium-rich material obtained in step (1) is dried, ground, and then mixed with sulfuric acid solution. Water is added or heated to carry out acid hydrolysis reaction, and solid-liquid separation is performed to obtain filtrate 1 and filter residue 1. Water is added to filtrate 1 and heated to carry out hydrolysis, and solid A is precipitated to obtain metatitanic acid. After drying, TiO2 is obtained. The obtained TiO2 is mixed with sodium hydroxide aqueous solution to carry out hydrothermal reaction, and solid B is precipitated to obtain sodium titanate (Na2TiO3). After washing with water, drying, and grinding, sodium titanate powder is obtained.

[0017] (3) Silicon powder treatment: Mix the silicon powder obtained in step (1) with water to obtain a dilute silicon powder solution;

[0018] (4) Preparation of adsorbent precursor: The sodium titanate powder obtained in step (2) is mixed with hydrochloric acid aqueous solution, and the solid and liquid are separated to obtain filtrate 2; filtrate 2 is mixed with the silicon powder dilute liquid obtained in step (3), and heated for hydrolysis to obtain adsorbent precursor TiO2-SiO2.

[0019] (5) Preparation of adsorbent conversion: The adsorbent precursor TiO2-SiO2 obtained in step (4) is mixed with lithium carbonate and calcined to obtain Li2TiO3-SiO2. Then it is mixed with hydrochloric acid aqueous solution, and solid-liquid separation is performed to obtain a solid. The solid is washed and dried to obtain the lithium adsorbent.

[0020] In some embodiments, the mass ratio of the titanium-rich material to the sulfuric acid solution in step (2) is 1:1.4-1:2. In some embodiments, the mass ratio of the titanium-rich material to the sulfuric acid solution in step (2) is 1:1.6-1:1.8. In some embodiments, the mass ratio of the titanium-rich material to the sulfuric acid solution in step (2) is 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, or 1:2.

[0021] In some embodiments, the sulfuric acid solution in step (2) is an aqueous sulfuric acid solution of 80 wt% or higher. In some embodiments, the sulfuric acid solution in step (2) is an aqueous sulfuric acid solution of 80 wt% to 98.3 wt%. In some embodiments, the sulfuric acid solution in step (2) is an aqueous sulfuric acid solution of 80 wt% to 90 wt%. In some embodiments, the sulfuric acid solution in step (2) is an aqueous sulfuric acid solution of 80 wt%, 85 wt%, 90 wt%, 95 wt%, or 98.3 wt%.

[0022] In some embodiments, the sulfuric acid solution in step (2) is an aqueous solution of sulfuric acid of 80wt% to 90wt% (e.g., 80wt%, 85wt%, 90wt%), and the acidolysis reaction is carried out under heating conditions.

[0023] In some embodiments, the sulfuric acid solution in step (2) is 80 wt% or more or 80 wt% to 98.3 wt% (e.g., 80 wt%, 85 wt%, 90 wt%, 95 wt%, or 98.3 wt%), and the acidolysis reaction is carried out under heat after adding water and releasing heat.

[0024] In some embodiments, the sulfuric acid solution in step (2) is 80 wt% or more or 80 wt% to 98.3 wt%, and the acidolysis reaction is carried out after adding water and releasing heat and keeping warm; the mass ratio of water to sulfuric acid solution in the acidolysis reaction is 1:6 to 1:8 (e.g., 1:6, 1:7 or 1:8).

[0025] In some embodiments, the reaction temperature of the acidolysis reaction in step (2) is above 200°C. In some preferred embodiments, the reaction temperature of the acidolysis reaction in step (2) is above 240°C or above 250°C. In some embodiments, the reaction temperature of the acidolysis reaction in step (2) is 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 280°C, 290°C, or 300°C.

[0026] In some embodiments, the reaction time of the acidolysis reaction in step (2) is 1 hour or more. In some embodiments, the reaction time of the acidolysis reaction in step (2) is 1.5 hours or more. In some embodiments, the reaction time of the acidolysis reaction in step (2) is 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours, or 4 hours.

[0027] In some embodiments, the concentration of the hydrochloric acid aqueous solution in step (4) is 15 wt% to 20 wt%. In some embodiments, the concentration of the hydrochloric acid aqueous solution in step (4) is 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, or 20 wt%.

[0028] In some embodiments, in step (4), each 1g of sodium titanate powder is mixed with 20ml to 30ml of hydrochloric acid aqueous solution. In some embodiments, in step (4), each 1g of sodium titanate powder is mixed with 20ml, 21ml, 22ml, 23ml, 24ml, 25ml, 26ml, 27ml, 28ml, 29ml, or 30ml of hydrochloric acid aqueous solution.

[0029] In some embodiments, the clay-type lithium ore contains titanium.

[0030] In some embodiments, the titanium content in the clay-type lithium ore is 1 wt% to 5 wt%. In some embodiments, the titanium content in the clay-type lithium ore is 1 wt%, 2 wt%, 3 wt%, 4 wt%, or 5 wt%.

[0031] In some embodiments, the volume ratio of filtrate 2 in step (4) to the dilute silicon powder solution obtained in step (3) is 1:30 to 1:70. In some embodiments, the volume ratio of filtrate 2 in step (4) to the dilute silicon powder solution obtained in step (3) is 1:30, 1:35, 1:40, 1:45, 1:50, 1:55, 1:60, 1:65, or 1:70. In some preferred embodiments, the volume ratio of filtrate 2 in step (4) to the dilute silicon powder solution obtained in step (3) is 1:50.

[0032] In some embodiments, the silicon powder content in the dilute silicon powder solution is 0.05 wt% to 0.40 wt%. In some embodiments, the silicon powder content in the dilute silicon powder solution is 0.05 wt%, 0.10 wt%, 0.15 wt%, 0.20 wt%, 0.25 wt%, 0.30 wt%, 0.35 wt%, or 0.40 wt%.

[0033] In some embodiments, the method for preparing the acid leaching residue of the clay-type lithium ore includes acid leaching the clay-type lithium ore with concentrated sulfuric acid, followed by water leaching, and then solid-liquid separation to obtain the acid leaching residue of the clay-type lithium ore.

[0034] In some embodiments, the clay-type lithium ore is crushed before being acidified with sulfuric acid.

[0035] In some embodiments, the concentrated sulfuric acid is an aqueous solution of sulfuric acid with a concentration of 85 wt% to 90 wt%.

[0036] In some embodiments, the concentrated sulfuric acid acidolysis temperature in the method for preparing the acidolysis residue of clay-type lithium ore is 200℃~250℃. In some embodiments, the concentrated sulfuric acid acidolysis temperature in the method for preparing the acidolysis residue of clay-type lithium ore is 200℃, 210℃, 220℃, 230℃, 240℃ or 250℃.

[0037] In some embodiments, the mass ratio of clay-type lithium ore to concentrated sulfuric acid during acid hydrolysis is 1:1.4 to 1:2. In some embodiments, the mass ratio of clay-type lithium ore to concentrated sulfuric acid during acid hydrolysis is 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, or 1:2.

[0038] In some embodiments, the concentrated sulfuric acid acidolysis time in the method for preparing the acidolysis residue of clay-type lithium ore is 60 min to 360 min. In some embodiments, the concentrated sulfuric acid acidolysis time in the method for preparing the acidolysis residue of clay-type lithium ore is 60 min, 70 min, 80 min, 85 min, 90 min, 95 min, 100 min, 120 min, 150 min, 200 min, 240 min, 250 min, 300 min, or 360 min.

[0039] In some embodiments, the leaching temperature during the water leaching operation is 80°C to 90°C. In some embodiments, the leaching temperature during the water leaching operation is 80°C, 85°C, or 90°C.

[0040] In some embodiments, during the water leaching operation, the mass ratio of the clay-type lithium ore to water is 1:2 to 1:4. In some embodiments, during the water leaching operation, the mass ratio of the clay-type lithium ore to water is 1:2, 1:3, or 1:4.

[0041] In some embodiments, during the water leaching operation, the leaching time after adding water is 1 hour to 4 hours. In some embodiments, during the water leaching operation, the leaching time after adding water is 1 hour, 2 hours, 3 hours, or 4 hours.

[0042] In some embodiments, the separation includes flotation separation or gravity separation.

[0043] In some embodiments, the flotation separation includes slurrying the acid leaching residue of clay-type lithium ore with water, adjusting the pH, and then mixing it with titanium dioxide collector, gangue inhibitor, auxiliary reagents and frother, followed by flotation and separation.

[0044] In some embodiments, the titanium dioxide collector comprises at least one of benzylarsonic acid and sodium hydroxamate.

[0045] In some embodiments, the gangue inhibitor includes at least one of carboxymethyl cellulose, sodium fluorosilicate, aluminum sulfate, and starch.

[0046] In some embodiments, the adjuvant agent includes a pH adjuster and an activator.

[0047] In some embodiments, the pH adjuster includes sodium carbonate.

[0048] In some embodiments, the activator includes lead acetate.

[0049] In some embodiments, the foaming agent includes at least one selected from pine oil, methyl isobutyl alcohol, polyethylene glycol ether foaming agents, and fatty acid ethyl ester foaming agents. In some preferred embodiments, the foaming agent is pine oil.

[0050] In some embodiments, the flotation separation includes roughing and cleaning, wherein the roughing uses carboxymethyl cellulose and sodium fluorosilicate as gangue inhibitors, and the cleaning uses aluminum sulfate and starch as gangue inhibitors.

[0051] In some embodiments, the coarse selection is performed once or twice.

[0052] In some embodiments, the selection is performed once or twice.

[0053] In some embodiments, the roughing process includes: a first roughing process: the acid slurry of clay-type lithium ore is slurried with water to adjust the pH, and then mixed with titanium dioxide collector, gangue inhibitor, activator and frother, and floated to obtain frothy concentrate 1 and precipitate 1, wherein precipitate 1 is roughing mud.

[0054] In some embodiments, the roughing further includes a second roughing: the precipitate 1 is slurried with water to adjust the pH, and then mixed with titanium dioxide collector, gangue inhibitor, activator and frother, and floated to obtain frothy concentrate 2 and precipitate 2, wherein the precipitate 2 is the roughing mud.

[0055] In some embodiments, the refining includes: a first refining: adjusting the froth concentrate obtained from the roughing process with water, wherein the froth concentrate obtained from the roughing process is froth concentrate 1 and / or froth concentrate 2; adjusting the pH, and then mixing it with titanium dioxide collector, gangue inhibitor and activator, and flotation to obtain froth concentrate 3 and precipitate 3, wherein the precipitate 3 is the refined mud.

[0056] In some embodiments, the refining further includes a second refining: the foam concentrate 3 is mixed with water and floated to obtain foam concentrate 4 and precipitate 4, wherein the precipitate 3 and precipitate 4 are refined mud.

[0057] In some embodiments, the rough mud obtained from the roughing process and the refined mud obtained from the cleaning process are combined to obtain the mud.

[0058] In some embodiments, the foam concentrate 3 or foam concentrate 4 is the titanium-rich material.

[0059] In some embodiments, the concentration of the clay-type acid hydrolysis residue after water slurry conditioning in the first roughing stage is 20 wt% to 30 wt%. In some embodiments, the concentration of the clay-type acid hydrolysis residue after water slurry conditioning in the first roughing stage is 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, or 30 wt%.

[0060] In some embodiments, during the first roughing process, 550g to 750g of titanium dioxide collector is added to every ton of acid leaching residue from clay-type lithium ore. In other embodiments, during the first roughing process, 550g, 600g, 650g, 700g, or 750g of titanium dioxide collector is added to every ton of acid leaching residue from clay-type lithium ore.

[0061] In some embodiments, during the first roughing process, 850g to 1050g of gangue inhibitor is added to each ton of acid leaching residue from clay-type lithium ore. In some embodiments, during the first roughing process, 850g, 900g, 950g, 1000g, or 1050g of gangue inhibitor is added to each ton of acid leaching residue from clay-type lithium ore.

[0062] In some embodiments, during the first roughing process, 300g to 400g of activator is added to each ton of acid leaching residue from clay-type lithium ore. In other embodiments, during the first roughing process, 300g, 350g, or 400g of activator is added to each ton of acid leaching residue from clay-type lithium ore.

[0063] In some embodiments, during the first coarse selection, 30g of foaming agent is added for every ton of acid leaching residue from clay-type lithium ore.

[0064] In some embodiments, during the first coarse selection, the pH adjustment is to a pH of 8 to 8.5. In some embodiments, during the first coarse selection, the pH adjustment is to a pH of 8, 8.1, 8.2, 8.3, 8.4, or 8.5.

[0065] In some embodiments, the concentration of precipitate 1 after water conditioning in the second roughing process is 20 wt% to 30 wt%. In some embodiments, the concentration of precipitate 1 after water conditioning in the second roughing process is 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, or 30 wt%.

[0066] In some embodiments, during the second coarse selection, 275g to 375g of titanium dioxide collector is added per ton of precipitate 1. In some embodiments, during the second coarse selection, 275g, 280g, 285g, 290g, 295g, 300g, 305g, 310g, 315g, 320g, 325g, 330g, 335g, 340g, 345g, 350g, 355g, 360g, 365g, 370g, or 375g of titanium dioxide collector is added per ton of precipitate 1.

[0067] In some embodiments, during the second coarse selection, 425g to 525g of gangue inhibitor is added per ton of precipitate 1. In some embodiments, during the second coarse selection, 425g, 430g, 440g, 450g, 460g, 470g, 480g, 490g, 500g, 510g, 520g, or 525g of gangue inhibitor is added per ton of precipitate 1.

[0068] In some embodiments, during the second coarse selection, 150g to 200g of activator is added for every 1 ton of precipitate.

[0069] In some embodiments, during the second coarse selection, 10g-20g of foaming agent is added for every 1 ton of precipitate 1. In some embodiments, during the second coarse selection, 15g of foaming agent is added for every 1 ton of precipitate 1.

[0070] In some embodiments, during the second coarse selection, the pH adjustment is to adjust the pH to 8 to 8.5. In some embodiments, during the second coarse selection, the pH adjustment is to adjust the pH to 8, 8.1, 8.2, 8.3, 8.4, or 8.5.

[0071] In some embodiments, the total concentration of the froth concentrate obtained from the roughing process in the first cleaning step, after being slurried with water, is 20 wt% to 30 wt%. In some embodiments, the total concentration of the froth concentrate obtained from the roughing process in the first cleaning step, after being slurried with water, is 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, or 30 wt%.

[0072] In some embodiments, during the first fine-tuning process, 60g-80g of titanium dioxide collector is added per ton of the frothy concentrate obtained from the roughing process. In some embodiments, during the first fine-tuning process, 70g of titanium dioxide collector is added per ton of the frothy concentrate obtained from the roughing process.

[0073] In some embodiments, during the first fine-tuning process, 100g-300g of gangue inhibitor is added for every 1 ton of frothy concentrate obtained from the roughing process. In some embodiments, during the first fine-tuning process, 200g of gangue inhibitor is added for every 1 ton of frothy concentrate obtained from the roughing process.

[0074] In some embodiments, during the first fine-tuning process, 20g-40g of activator is added to every 1 ton of frothy concentrate obtained from the roughing process. In some embodiments, during the first fine-tuning process, 30g of activator is added to every 1 ton of frothy concentrate obtained from the roughing process.

[0075] In some embodiments, during the first fine-tuning process, the mass ratio of the froth concentrate obtained from the roughing process to water is 20:80 to 30:70. In some embodiments, the mass ratio of the froth concentrate obtained from the roughing process to water during the first fine-tuning process is 20:80, 21:79, 22:78, 23:77, 24:76, 25:75, 26:74, 27:73, 28:72, 29:71, or 30:70.

[0076] In some embodiments, during the first selection, the pH adjustment is to adjust the pH to 8 to 8.5. In some embodiments, during the first selection, the pH adjustment is to adjust the pH to 8, 8.1, 8.2, 8.3, 8.4, or 8.5.

[0077] In some embodiments, the concentration of foam concentrate 3 after mixing with water in the second purification process is 20 wt% to 30 wt%. In some embodiments, the concentration of foam concentrate 3 after mixing with water in the second purification process is 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, or 30 wt%.

[0078] In some embodiments, the gangue inhibitors in the first or second coarse selection are carboxymethyl cellulose and sodium fluorosilicate.

[0079] In some embodiments, the gangue inhibitor in the first or second roughing is carboxymethyl cellulose and sodium fluorosilicate in a mass ratio of 1:3 to 3:3. In some embodiments, the gangue inhibitor in the first or second roughing is carboxymethyl cellulose and sodium fluorosilicate in a mass ratio of 2:3.

[0080] In some embodiments, the titanium dioxide collectors used in the first roughing, second roughing, or first fine selection are benzylarsine and sodium hydroxamate.

[0081] In some embodiments, the mass ratio of benzylarsine and sodium hydroxamate in the titanium dioxide collectors obtained from the first roughing, second roughing, or first cleaning is independently selected from 1:2 to 1:4. In some embodiments, the mass ratio of benzylarsine and sodium hydroxamate in the titanium dioxide collectors obtained from the first roughing, second roughing, or first cleaning is independently selected from 1:2, 2:5, 1:3, or 1:4.

[0082] In some embodiments, the first selected gangue inhibitors are aluminum sulfate and starch.

[0083] In some embodiments, the first selected gangue inhibitor is aluminum sulfate and starch in a mass ratio of 2:1 to 1:2. In some embodiments, the selected gangue inhibitor is aluminum sulfate and starch in a mass ratio of 1:1.

[0084] In some embodiments, the pH adjustment for the first coarse selection, the second coarse selection, or the first fine selection is achieved using sodium carbonate.

[0085] In some embodiments, the titanium-rich material in step (2) is ground to a particle size D90 of 38 micrometers to 75 micrometers.

[0086] In some embodiments, the silicon powder in step (3) is ground to a particle size of less than or equal to 38 micrometers before being mixed with water.

[0087] In some embodiments, the precipitation of solid A in step (2) includes heating to precipitate solid A, or adding seed crystals after adding water to the filtrate 1 and heating to perform hydrolysis, thereby precipitating solid A.

[0088] In some embodiments, in step (2), the mass ratio of filtrate 1 to water in the operation of adding water to filtrate 1 and heating for hydrolysis is 1:3-1:5. In some embodiments, in step (2), the mass ratio of filtrate 1 to water in the operation of adding water to filtrate 1 and heating for hydrolysis is 1:4.

[0089] In some embodiments, the temperature at which the filtrate 1 is added to water and heated for hydrolysis in step (2) is 80-90°C. In some embodiments, the temperature at which the filtrate 1 is added to water and heated for hydrolysis in step (2) is 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C, or 90°C. In some embodiments, the temperature at which the filtrate 1 is added to water and heated for hydrolysis in step (2) is 90°C.

[0090] In some embodiments, the hydrolysis time for adding water and heating the filtrate 1 in step (2) is 1h-5h. In some embodiments, the hydrolysis time for adding water and heating the filtrate 1 in step (2) is 1h, 2h, 3h, 4h or 5h.

[0091] In some embodiments, the concentration of the sodium hydroxide aqueous solution in step (2) is 10 mol / L to 15 mol / L. In some embodiments, the concentration of the sodium hydroxide aqueous solution in step (2) is 10 mol / L, 11 mol / L, 12 mol / L, 13 mol / L, 14 mol / L, or 15 mol / L.

[0092] In some embodiments, in step (2), 80 ml to 120 ml of sodium hydroxide aqueous solution is added for every 1 g of TiO2 powder. In some embodiments, 80 ml, 85 ml, 90 ml, 95 ml, 100 ml, 105 ml, 110 ml, 115 ml, or 120 ml of sodium hydroxide aqueous solution is added for every 1 g of TiO2 powder in step (2).

[0093] In some embodiments, the temperature of the hydrothermal reaction in step (2) is 180–220°C. In some embodiments, the temperature of the hydrothermal reaction in step (2) is 180°C, 190°C, 200°C, 210°C, or 220°C.

[0094] In some embodiments, the hydrothermal reaction time in step (2) is 24h to 30h. In some embodiments, the hydrothermal reaction time in step (2) is 24h, 25h, 26h, 27h, 28h, 29h, or 30h.

[0095] In some embodiments, the heating temperature in step (4) is 90°C to 95°C. In some embodiments, the heating temperature in step (4) is 90°C, 91°C, 92°C, 93°C, 94°C, or 95°C.

[0096] In some embodiments, the heating and hydrolysis time in step (4) is 3 to 4 hours.

[0097] In some embodiments, in step (5), the adsorbent precursor TiO2-SiO2 and lithium carbonate are fed in a lithium:titanium molar ratio of 2:1 to 2.5:1. In some embodiments, in step (5), the adsorbent precursor TiO2-SiO2 and lithium carbonate are fed in a lithium:titanium molar ratio of 2:1, 2.1:1, 2.2:1, 2.3:1, 2.4:1, or 2.5:1.

[0098] In some embodiments, the roasting temperature in step (5) is 600°C to 700°C. In some embodiments, the roasting temperature in step (5) is 600°C, 650°C, or 700°C.

[0099] In some embodiments, the roasting time in step (5) is 4h to 6h. In some embodiments, the roasting time in step (5) is 4h, 4.5h, 5h, 5.5h or 6h.

[0100] In some embodiments, the concentration of the hydrochloric acid aqueous solution in step (5) is 1 wt% to 2 wt%.

[0101] In some embodiments, the seed crystal is titanium dioxide or its hydrate.

[0102] In some embodiments, the mass ratio of titanium in the seed crystal to titanium in the filtrate 1 is 1:20 to 1:25. In some embodiments, the mass ratio of titanium in the seed crystal to titanium in the filtrate 1 is 1:20, 1:21, 1:22, 1:23, 1:24, or 1:25.

[0103] In some embodiments, the heating for the precipitation of solid A is heating to 90°C to 95°C. In some embodiments, the heating for the precipitation of solid A is heating to 90°C, 91°C, 92°C, 93°C, 94°C, or 95°C.

[0104] In a second aspect, the present invention provides a lithium adsorbent prepared by the preparation method described in the first aspect.

[0105] A lithium adsorbent prepared by the preparation method described in the first aspect.

[0106] Thirdly, the present invention provides an application of the lithium adsorbent prepared by the preparation method described in the first aspect or the lithium adsorbent described in the second aspect.

[0107] The application of a lithium adsorbent prepared by the preparation method of the first aspect or the lithium adsorbent of the second aspect in the adsorption of lithium in salt lake brine.

[0108] Beneficial effects

[0109] Compared with the prior art, the technical solution of the present invention has the following beneficial technical effects:

[0110] (1) This invention uses acid leaching residue from clay-type lithium ore to prepare lithium adsorbent, thereby making high-value use of the residue and reducing environmental pollution, which is conducive to industrial development.

[0111] (2) The method for preparing lithium adsorbent provided by the present invention is simple to operate, safe, environmentally friendly, energy-efficient and low-cost.

[0112] (3) The lithium adsorbent provided by the present invention has high saturated Li adsorption capacity, high Li elution rate, and low adsorbent loss, and has excellent performance.

[0113] (4) Compared with other contents of silicon powder in the silicon powder dilute liquid in step (3) (such as 0.5wt% or 0.03wt%), the lithium adsorbent obtained by using the silicon powder content (0.05wt%-0.40wt%) in the silicon powder dilute liquid provided by the present invention has a significantly higher saturated Li adsorption capacity and has unexpected technical effects.

[0114] (5) Compared with other concentrations of hydrochloric acid aqueous solution in step (4) (such as 10wt% or 25wt%), the lithium adsorbent obtained by using the concentration of hydrochloric acid aqueous solution in step (4) provided by the present invention (15wt%-20wt%) has a significantly higher saturated Li adsorption capacity and lower adsorbent loss, which has unexpected technical effects.

[0115] Terminology Explanation

[0116] In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0117] The term “room temperature” refers to ambient temperature, which is between approximately 10°C and approximately 30°C, or approximately 20°C and approximately 30°C, or approximately 25°C.

[0118] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0119] In the following content, all figures disclosed herein, whether or not they use words such as "approximately" or "about," are approximate values. The value of each figure may vary by 1%, 2%, 5%, 7%, 8%, 10%, 15%, or 20%, etc. Whenever a figure with a value of N is disclosed, any figure with a value of N+ / -1%, N+ / -2%, N+ / -3%, N+ / -5%, N+ / -7%, N+ / -8%, N+ / -10%, N+ / -15%, or N+ / -20% will be explicitly disclosed, where "+ / -" indicates addition or subtraction. Detailed Implementation

[0120] To enable those skilled in the art to better understand the technical solutions of the present invention, some non-limiting embodiments are further disclosed below to provide a more detailed description of the present invention.

[0121] The reagents or consumables used in this invention can be purchased from the market or prepared by the methods described in this invention.

[0122] Unless otherwise stated, the methods for preparing acid leaching residue, titanium-rich material, and silicon powder used in the embodiments or comparative examples of the present invention are as follows:

[0123] I. Preparation of acid leaching residue from clay-type lithium ore:

[0124] Clay-type lithium ore with a titanium content of 1wt%-5wt% is mixed with 90wt% (or 85wt%-90wt%) of sulfuric acid aqueous solution at a mass ratio of clay-type lithium ore: sulfuric acid aqueous solution of 1:1.6. The mixture is reacted at 250℃ for 90 min, and the solid and liquid are separated to obtain acid leaching residue of clay-type lithium ore.

[0125] Table 1 is a multi-element analysis table of acid leaching residues of clay-type lithium ore used in the following examples and comparative examples.

[0126] Table 1: Multi-element analysis of acid leaching residue from clay-type lithium ore

[0127] element Li Al K Na content / % 0.012 0.77 0.068 0.024 element Fe Ti Mg Ca content / % 0.05 1.885 0.028 0.005

[0128] II. Preparation of Titanium-Rich Materials and Silicon Powder

[0129] The acid leaching residue from clay-type lithium ore undergoes two roughing and two cleaning processes to obtain titanium-rich material and silicon powder; the specific operation is as follows:

[0130] First roughing: The acid leaching residue of clay-type lithium ore is mixed with water to obtain a slurry, wherein the concentration of acid leaching residue of clay-type lithium ore in the slurry is 20wt%-30wt%; the pH is adjusted to 8.5 with sodium carbonate to obtain slurry 1. Titanium dioxide collector (benzylarsonic acid and sodium hydroxamic acid), gangue inhibitor (carboxymethyl cellulose and sodium fluorosilicate), activator (lead acetate), and frother (pine oil) are added before flotation to obtain frothy concentrate 1 and precipitate 1; wherein, in the first roughing, 200g benzylarsonic acid, 500g sodium hydroxamic acid, 400g carboxymethyl cellulose, 600g sodium fluorosilicate, 300g lead acetate and 30g pine oil are added for every ton of acid leaching residue of clay-type lithium ore.

[0131] Second roughing: Precipitator 1 is slurry prepared with water, containing 20wt%-30wt% precipitate 1. The pH is adjusted to 8.5 with sodium carbonate, followed by the addition of titanium dioxide collectors (benzylarsonic acid and sodium hydroxamic acid), gangue inhibitors (carboxymethyl cellulose and sodium fluorosilicate), activator lead acetate, and frother (pine oil). Flotation is then performed to obtain frothy concentrate 2 and precipitate 2. In the second roughing, 100g benzylarsonic acid, 250g sodium hydroxamic acid, 200g carboxymethyl cellulose, 300g sodium fluorosilicate, 150g lead acetate, and 15g pine oil are added per ton of precipitate 1.

[0132] First Refinement: Foam concentrate 1 and foam concentrate 2 are mixed with water to obtain a slurry, the total concentration of foam concentrate 1 and foam concentrate 2 in the slurry being 20wt%-30wt%. The pH is adjusted to 8.5 with sodium carbonate, and then titanium dioxide collectors (benzylarsonic acid and sodium hydroxamate), gangue inhibitors (aluminum sulfate and starch), and activator (lead acetate) are added. Flotation is then performed to obtain foam concentrate 3 and precipitate 3. In the first refinement, for every ton of total mass of foam concentrate 1 and foam concentrate 2, 20g of benzylarsonic acid, 50g of sodium hydroxamate, 100g of aluminum sulfate, 100g of starch, and 30g of lead acetate are added.

[0133] Second fine selection: Water is added to the frothy concentrate 3 to prepare a slurry, wherein the concentration of concentrate 3 in the slurry is 20wt%-30wt%; flotation is performed to obtain frothy concentrate 4 and precipitate 4.

[0134] The precipitates 2, 3, and 4 are combined, dried, and used as silicon powder; foam concentrate 4 is used as titanium-rich material.

[0135] Example 1: Preparation of lithium adsorbent

[0136] (1) The acid slag from clay-type lithium ore is subjected to two roughing and two cleaning processes to obtain titanium-rich material and silicon powder;

[0137] (2) The titanium-rich material was dried and ball-milled to a particle size of less than or equal to 75 micrometers (passing through 200 mesh), and then mixed with 85wt% sulfuric acid aqueous solution. The mass ratio of the titanium-rich material to the sulfuric acid aqueous solution was 1:1.6. The mixture was subjected to acid hydrolysis at 250℃ for 30 min, and then kept warm for 1 h. After acid hydrolysis, solid and liquid were separated to obtain filtrate 1. The obtained filtrate 1 was mixed with water at a mass ratio of filtrate 1:water = 1:4 and then heated at 90℃ for 1 h to precipitate solid A, which yielded metatitanic acid (hydrated titanium dioxide). The metatitanic acid was dried at 200℃ for 4 h to obtain titanium dioxide powder. Titanium dioxide powder and 10mol / L sodium hydroxide aqueous solution were mixed at a ratio of 100 ml of 10mol / L sodium hydroxide aqueous solution for every 1 g of titanium dioxide powder, and then subjected to hydrothermal reaction at 200℃ for 24 h to precipitate solid B, which yielded sodium titanate. The obtained sodium titanate was washed with water, dried, and ground to obtain sodium titanate powder.

[0138] (3) The silicon powder obtained in step (1) is dried and then ground to 38 micrometers or less, and then mixed with water to obtain a silicon powder dilute liquid, wherein the silicon powder content in the silicon powder dilute liquid is 0.25 wt%.

[0139] (4) Mix sodium titanate powder with 20wt% hydrochloric acid aqueous solution (each 1g sodium titanate powder is mixed with 20mL of 20wt% hydrochloric acid aqueous solution), filter to obtain filtrate 2, mix filtrate 2 with the silicon powder dilute liquid obtained in step (3) to obtain mixture 4, wherein the volume ratio of filtrate 2 to dilute liquid is 1:50, and the precursor material is obtained by heating mixture 4 to 95°C and hydrolyzing for 4h.

[0140] (5) The precursor material and lithium carbonate are mixed at a molar ratio of Li:Ti = 2:1, and then calcined at 600°C for 4 hours to convert it into Li2TiO3-SiO2. The lithium is eluted with 2wt% hydrochloric acid aqueous solution to obtain the adsorbent. Solid-liquid separation is performed to obtain a solid. The obtained solid is washed and dried to obtain the lithium adsorbent.

[0141] Example 2: Preparation of lithium adsorbent

[0142] The preparation was carried out according to the method of Example 1, with the following difference:

[0143] The concentration of the sulfuric acid aqueous solution in step (2) is 80 wt%; the concentration of the sodium hydroxide aqueous solution is 12 mol / L; the ratio of titanium dioxide powder to 12 mol / L sodium hydroxide aqueous solution is 80 ml of 12 mol / L sodium hydroxide aqueous solution for every 1 g of titanium dioxide powder; the reaction temperature of the reaction after mixing the titanium dioxide powder and the sodium hydroxide aqueous solution is 180℃, and the reaction time is 28 h.

[0144] The silicon powder content in the silicon powder dilute solution in step (3) is 0.40 wt%.

[0145] The concentration of the hydrochloric acid aqueous solution in step (4) is 16 wt%.

[0146] The calcination temperature in step (5) is 650°C, and the concentration of the hydrochloric acid aqueous solution in step (5) is 1 wt%.

[0147] The remaining reagents, procedures, and dosages are the same as in Example 1.

[0148] Example 3: Preparation of lithium adsorbent

[0149] The preparation was carried out according to the method of Example 1, with the following difference:

[0150] The concentration of the sulfuric acid aqueous solution in step (2) is 98 wt%; the mass ratio of the titanium-rich material to the sulfuric acid aqueous solution is 1:1.7; the concentration of the sodium hydroxide aqueous solution is 15 mol / L, and the ratio of titanium dioxide powder to 15 mol / L sodium hydroxide aqueous solution is 90 ml of 15 mol / L sodium hydroxide aqueous solution for every 1 g of titanium dioxide powder; the reaction temperature of the reaction after mixing the titanium dioxide powder and the sodium hydroxide aqueous solution is 190℃, and the reaction time is 26 h.

[0151] The silicon powder content in the dilute silicon powder solution in step (3) is 0.15 wt%; the concentration of the hydrochloric acid aqueous solution in step (4) is 15 wt%.

[0152] The concentration of the hydrochloric acid aqueous solution in step (5) is 1 wt%.

[0153] The remaining reagents, procedures, and dosages are the same as in Example 1.

[0154] Example 4: Preparation of lithium adsorbent

[0155] The preparation was carried out according to the method of Example 1, with the following difference:

[0156] In step (2), the mass ratio of the titanium-rich material to the sulfuric acid aqueous solution is 1:1.7; the concentration of the sodium hydroxide aqueous solution is 13 mol / L, and the ratio of titanium dioxide powder to 13 mol / L sodium hydroxide aqueous solution is 110 ml of 13 mol / L sodium hydroxide aqueous solution for every 1 g of titanium dioxide powder; the reaction temperature of the reaction after mixing the titanium dioxide powder and the sodium hydroxide aqueous solution is 180℃, and the reaction time is 30 h.

[0157] The silicon powder content in the dilute silicon powder solution in step (3) is 0.20 wt%.

[0158] The concentration of the hydrochloric acid aqueous solution in step (4) is 18 wt%; the concentration of the hydrochloric acid aqueous solution in step (5) is 1 wt%.

[0159] The roasting temperature in step (5) is 700℃;

[0160] The remaining reagents, procedures, and dosages are the same as in Example 1.

[0161] Example 5: Preparation of lithium adsorbent

[0162] The preparation was carried out according to the method of Example 1, with the following difference:

[0163] The concentration of the sulfuric acid aqueous solution in step (2) is 90 wt%; the ratio of titanium dioxide powder to 10 mol / L sodium hydroxide aqueous solution is 120 ml of 10 mol / L sodium hydroxide aqueous solution for every 1 g of titanium dioxide powder; the reaction temperature of the reaction after mixing the titanium dioxide powder and the sodium hydroxide aqueous solution is 180 °C and the reaction time is 25 h.

[0164] The concentration of the hydrochloric acid aqueous solution in step (4) is 15 wt%.

[0165] The roasting temperature in step (5) is 680℃;

[0166] The remaining reagents, procedures, and dosages are the same as in Example 1.

[0167] Example 6: Preparation of lithium adsorbent

[0168] The preparation was carried out according to the method of Example 1, with the following difference:

[0169] The concentration of the sulfuric acid aqueous solution in step (2) is 95 wt%; the concentration of the sodium hydroxide aqueous solution is 15 mol / L; the reaction temperature of the reaction after mixing the titanium dioxide powder and the sodium hydroxide aqueous solution is 220℃, and the reaction time is 26 h.

[0170] The silicon powder content in the silicon powder dilute solution in step (3) is 0.05 wt%.

[0171] The concentration of the hydrochloric acid aqueous solution in step (4) is 18 wt%.

[0172] The roasting temperature in step (5) is 680℃;

[0173] The remaining reagents, procedures, and dosages are the same as in Example 1.

[0174] Example 7: Preparation of lithium adsorbent

[0175] The preparation was carried out according to the method of Example 1, with the following difference:

[0176] The concentration of the sulfuric acid aqueous solution in step (2) is 80 wt%; the mass ratio of the titanium-rich material to the sulfuric acid aqueous solution is 1:1.8; the concentration of the sodium hydroxide aqueous solution is 13 mol / L; the ratio of titanium dioxide powder to 13 mol / L sodium hydroxide aqueous solution is 90 ml of 13 mol / L sodium hydroxide aqueous solution for every 1 g of titanium dioxide powder; the reaction temperature of the reaction after mixing the titanium dioxide powder and the sodium hydroxide aqueous solution is 210℃, and the reaction time is 27 h.

[0177] The silicon powder content in the silicon powder dilute solution in step (3) is 0.35 wt%.

[0178] The concentration of the hydrochloric acid aqueous solution in step (4) is 18 wt%.

[0179] The roasting temperature in step (5) is 620℃;

[0180] The remaining reagents, procedures, and dosages are the same as in Example 1.

[0181] Example 8: Preparation of lithium adsorbent

[0182] The preparation was carried out according to the method of Example 1, with the following difference:

[0183] The concentration of the sulfuric acid aqueous solution in step (2) is 80 wt%; the mass ratio of the titanium-rich material to the sulfuric acid aqueous solution is 1:1.8; the concentration of the sodium hydroxide aqueous solution is 15 mol / L; the ratio of titanium dioxide powder to 16 mol / L sodium hydroxide aqueous solution is 80 ml of 16 mol / L sodium hydroxide aqueous solution per 1 g of titanium dioxide powder; the reaction time of the reaction after mixing the titanium dioxide powder and the sodium hydroxide aqueous solution is 26 h.

[0184] The silicon powder content in the silicon powder dilute solution in step (3) is 0.25 wt%.

[0185] The calcination temperature in step (5) is 650°C, and the concentration of the hydrochloric acid aqueous solution in step (5) is 1 wt%.

[0186] The remaining reagents, procedures, and dosages are the same as in Example 1.

[0187] Example 1: Investigation of silicon powder content in dilute silicon powder solution

[0188] Referring to the operation of Example 1, the silicon powder content in the silicon powder dilute liquid in step (3) is adjusted to the volume ratio in Table 2.

[0189] Table 2: Investigation of silicon powder content in dilute silicon powder solution

[0190] Examples / Comparative Examples Silicon powder content in dilute silicon powder solution Comparative Example 1 0.5wt% Comparative Example 2 0.03wt%

[0191] Example 2: Concentration of hydrochloric acid aqueous solution in step (4)

[0192] Following the procedure in Example 1, the concentration of the hydrochloric acid aqueous solution in step (4) was adjusted to the concentration shown in Table 3.

[0193] Table 3: Concentration of hydrochloric acid aqueous solution in step (4)

[0194] Examples / Comparative Examples Step (4) Concentration of hydrochloric acid aqueous solution Comparative Example 3 25wt% Comparative Example 4 10wt%

[0195] Experimental Example 1: Study on the Adsorption Performance of Lithium Adsorbent

[0196] 1. Procedure: Take the lithium adsorbents obtained in the above examples or comparative examples and test their lithium adsorption capacity.

[0197] S1. Weigh 10g of the prepared lithium adsorbent and put it into 500mL of a solution with a lithium ion concentration of 100mg / L, a magnesium ion concentration of 10g / L, and a pH of 9. Stir at 200rpm for 3h to adsorb.

[0198] S2. After adsorption is complete, the adsorbent and solution are separated by filtration, and the filtrate is sent for analysis of lithium ion concentration.

[0199] S3. After rinsing the lithium adsorbent twice with 100 mL of deionized water, add 500 mL of 1% (wt%) dilute hydrochloric acid and stir at 200 rpm for 3 hours to decompose the adsorbent. Filter to separate the adsorbent and filtrate. Send the filtrate for analysis of lithium ion concentration. Dry the adsorbent and weigh it.

[0200] Steps S4 and S1-S3 are the adsorption and desorption process. After repeating steps S1-S3 20 times, the adsorbent loss is calculated.

[0201] 2. Calculation method

[0202] (1) The method for calculating the adsorption capacity of lithium is as follows:

[0203] q=(ρ0-ρ)V / m

[0204] In the formula: q represents the amount of Li adsorbent adsorbed per gram of lithium adsorbent. + The amount; ρ0 is Li + The initial concentration of Li; ρ represents the concentration of Li at different times. + The concentration of is V; the volume of the solution is V; and the mass of the adsorbent is m.

[0205] (2) Calculation method for lithium adsorbent solubility loss:

[0206] δ=(m0-m) / m0

[0207] In the formula: m0 is the initial mass of lithium adsorbent; m is the mass of adsorbent after desorption and drying.

[0208] 3. Results: See Table 4.

[0209] Table 4: Adsorption performance of lithium adsorbent

[0210]

[0211] Conclusion: As shown in Table 4:

[0212] (1) The lithium adsorbent provided by the present invention has high saturated Li adsorption capacity, high Li elution rate, and low adsorbent loss, and has excellent performance.

[0213] (2) Compared with other contents of silicon powder in the silicon powder dilute liquid in step (3) (such as 0.5 wt% (Comparative Example 1) or 0.03 wt% (Comparative Example 2)), the lithium adsorbent obtained by using the silicon powder content in the silicon powder dilute liquid provided by the present invention (0.05 wt%-0.40 wt% (Examples 1-Examples 8)) has a significantly higher saturated Li adsorption capacity, which has unexpected technical effects.

[0214] (3) Compared with other concentrations of hydrochloric acid aqueous solution in step (4) (such as 10wt% (Comparative Example 3) and 25wt% (Comparative Example 4)), the lithium adsorbent obtained by using the concentration of hydrochloric acid aqueous solution in step (4) provided by the present invention (15wt%-20wt% (Examples 1-Examples 8)) has a significantly higher saturated Li adsorption capacity and lower adsorbent loss, and has unexpected technical effects.

[0215] The method of this invention has been described through preferred embodiments. Those skilled in the art will readily be able to modify or appropriately alter and combine the methods and applications described herein within the scope, spirit, and context of this invention to implement and apply the technology of this invention. Those skilled in the art can refer to the content herein to appropriately improve process parameters. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included within the scope of this invention.

Claims

1. A method for preparing a lithium adsorbent, characterized in that, include: (1) Lithium slag treatment: The acid slag of clay-type lithium ore is separated by sorting to obtain mud and titanium-rich material. The mud is dried to obtain silicon powder. (2) Titanium-rich material treatment: The titanium-rich material obtained in step (1) is dried, ground, and then mixed with sulfuric acid solution. Water is added or heated to carry out acid hydrolysis reaction, and solid-liquid separation is carried out to obtain filtrate 1 and filter residue 1. Water is added to filtrate 1 and heated to carry out hydrolysis, and solid A is precipitated to obtain metatitanic acid. After drying, TiO2 is obtained. The obtained TiO2 is mixed with sodium hydroxide aqueous solution to carry out hydrothermal reaction, and solid B is precipitated to obtain sodium titanate. After washing with water, drying, and grinding, sodium titanate powder is obtained. (3) Silicon powder treatment: Mix the silicon powder obtained in step (1) with water to obtain a dilute silicon powder solution; (4) Preparation of adsorbent precursor: The sodium titanate powder obtained in step (2) is mixed with hydrochloric acid aqueous solution, and the solid and liquid are separated to obtain filtrate 2; filtrate 2 is mixed with the silicon powder dilute liquid obtained in step (3), and heated for hydrolysis to obtain adsorbent precursor TiO2-SiO2. (5) Preparation of adsorbent conversion: The adsorbent precursor TiO2-SiO2 obtained in step (4) is mixed with lithium carbonate and calcined to obtain Li2TiO3-SiO2. Then it is mixed with hydrochloric acid aqueous solution, and solid-liquid separation is performed to obtain a solid. The solid is washed and dried to obtain the lithium adsorbent.

2. According to the preparation method of claim 1, the mass ratio of the titanium-rich material to the sulfuric acid solution in step (2) is 1:1.4-1:2 or 1:1.6-1:1.8; and / or The sulfuric acid solution in step (2) is an aqueous solution of sulfuric acid with a concentration of 80 wt% or higher, an aqueous solution of sulfuric acid with a concentration of 80 wt% to 98.3 wt%, or an aqueous solution of sulfuric acid with a concentration of 80 wt% to 90 wt%; and / or The sulfuric acid solution in step (2) is an 80wt%–90wt% aqueous sulfuric acid solution, and the acidolysis reaction is carried out under heating conditions; and / or In step (2), the sulfuric acid solution is 80 wt% or higher, or 80 wt% to 98.3 wt%, and the acidolysis reaction is carried out under heat after the addition of water and subsequent exothermic reaction; and / or In step (2), the sulfuric acid solution is 80 wt% or more, or 80 wt% to 98.3 wt%; the acidolysis reaction is carried out after adding water and releasing heat, and then maintaining the temperature; the mass ratio of water to sulfuric acid solution in the acidolysis reaction is 1:6 to 1:8; and / or The acidolysis reaction in step (2) is carried out at a temperature of 200°C or higher, preferably 240°C or higher or 250°C or higher; and / or The acidolysis reaction in step (2) takes more than 1 hour, or more than 1.5 hours; and / or The concentration of the hydrochloric acid aqueous solution in step (4) is 15wt% to 20wt%; and / or In step (4), each 1g of sodium titanate powder is mixed with 20-30ml or 20ml of hydrochloric acid aqueous solution.

3. The preparation method according to any one of claims 1 to 2, wherein the clay-type lithium ore contains titanium; and / or The titanium content in the clay-type lithium ore is 1 wt% to 5 wt%, or 2 wt%; and / or In step (4), the volume ratio of filtrate 2 to the dilute silica powder solution obtained in step (3) is 1:30 to 1:70 or 1:50; and / or The silicon powder content in the dilute silicon powder solution is 0.05wt% to 0.40wt%.

4. The preparation method according to any one of claims 1 to 3, wherein the preparation method of the acid hydrolysis residue of the clay-type lithium ore includes acid hydrolysis of the clay-type lithium ore with concentrated sulfuric acid, followed by leaching with water and solid-liquid separation to obtain the acid hydrolysis residue of the clay-type lithium ore; Optionally, the clay-type lithium ore is crushed before sulfuric acid acidolysis; and / or Optionally, the concentrated sulfuric acid is an 85wt% to 90wt% aqueous solution of sulfuric acid; and / or Optionally, the concentrated sulfuric acid acidolysis temperature in the method for preparing the acidolysis residue of the clay-type lithium ore is 200℃~250℃; and / or Optionally, during acid hydrolysis, the mass ratio of the clay-type lithium ore to concentrated sulfuric acid is 1:1.4 to 1:2; and / or Optionally, the concentrated sulfuric acid acidolysis time in the method for preparing the acidolysis residue of the clay-type lithium ore is 60 min to 360 min; and / or Optionally, in the water leaching operation, the leaching temperature is 80–90°C; and / or Optionally, in the water leaching operation, the mass ratio of the clay-type lithium ore to water is 1:2 to 1:4; and / or Optionally, in the water leaching operation, the leaching time after adding water is 1 hour to 4 hours.

5. The preparation method according to any one of claims 1 to 4, wherein the separation comprises flotation separation or gravity separation; and / or The flotation separation includes slurrying the acid leaching residue of clay-type lithium ore with water, adjusting the pH, and then mixing it with titanium dioxide collector, gangue inhibitor, auxiliary reagents and frother, followed by flotation and separation. Optionally, the titanium dioxide collector comprises at least one of benzylarsonic acid and sodium hydroxamate; and / or optionally, the gangue inhibitor comprises at least one of carboxymethyl cellulose, sodium fluorosilicate, aluminum sulfate, and starch; and / or Optionally, the auxiliary agents include pH adjusters and activators; and / or Optionally, the pH adjuster includes sodium carbonate; and / or Optionally, the activator includes lead acetate; and / or Optionally, the foaming agent includes at least one of pine oil, methyl isobutyl alcohol, polyethylene glycol ether foaming agents, and fatty acid ethyl ester foaming agents, preferably pine oil; and / or Optionally, the flotation separation includes roughing and cleaning, wherein the roughing uses carboxymethyl cellulose and sodium fluorosilicate as gangue inhibitors, and the cleaning uses aluminum sulfate and starch as gangue inhibitors; and / or optionally, the roughing is performed once or twice; and / or Optionally, the selection is performed once or twice; and / or Optionally, the roughing process includes: a first roughing process: the acid leaching residue of clay-type lithium ore is slurried with water to adjust the pH, then mixed with titanium dioxide collector, gangue inhibitor, activator and frother, and floated to obtain frothy concentrate 1 and precipitate 1, wherein precipitate 1 is the roughing mud; and / or Optionally, the roughing further includes a second roughing: precipitate 1 is slurried with water to adjust the pH, then mixed with titanium dioxide collector, gangue inhibitor, activator, and frother, and floated to obtain frothy concentrate 2 and precipitate 2, wherein precipitate 2 is the roughing mud; and / or Optionally, the refining process includes: a first refining step: adjusting the froth concentrate obtained from the roughing process with water, wherein the froth concentrate obtained from the roughing process is froth concentrate 1 and / or froth concentrate 2; adjusting the pH, and then mixing with titanium dioxide collector, gangue inhibitor, and activator, followed by flotation to obtain froth concentrate 3 and precipitate 3, wherein precipitate 3 is the refining mud; and / or Optionally, the refining further includes a second refining process: mixing the froth concentrate 3 with water, flotation to obtain froth concentrate 4 and precipitate 4, wherein precipitate 3 and precipitate 4 are refining slurry; and / or Optionally, the roughing mud obtained from the roughing process and the cleaning mud obtained from the cleaning process are combined to obtain the mud; and / or Optionally, the foam concentrate 3 or foam concentrate 4 is the titanium-rich material; and / or Optionally, the clay-type acid hydrolysis residue in the first roughing stage, after being slurried with water, has a clay-type acid hydrolysis residue concentration of 20 wt% to 30 wt%; and / or Optionally, in the first roughing process, 550g to 750g of titanium dioxide collector is added to every ton of acid leaching residue from clay-type lithium ore; and / or Optionally, in the first roughing process, 850g to 1050g of gangue inhibitor is added to each ton of acid leaching residue from clay-type lithium ore; and / or Optionally, in the first roughing process, 300g to 400g of activator is added to each ton of acid leaching residue from clay-type lithium ore; and / or Optionally, in the first roughing process, 30g of frother is added for every ton of acid leaching residue from clay-type lithium ore; and / or Optionally, in the first coarse selection, the pH adjustment is to adjust the pH to 8-8.5; and / or Optionally, in the second roughing process, the concentration of precipitate 1 after water conditioning is 20 wt% to 30 wt%; and / or Optionally, in the second coarse selection, 275g to 375g of titanium dioxide collector is added for every 1 ton of precipitate; and / or Optionally, in the second coarse selection, 425g to 525g of gangue inhibitor is added for every 1 ton of precipitate; and / or Optionally, in the second coarse selection, 150g to 200g of activator is added for every 1 ton of precipitate; and / or Optionally, in the second coarse selection, 10g-20g or 15g of foaming agent is added for every 1 ton of precipitate; and / or Optionally, in the second coarse selection, the pH adjustment is to adjust the pH to 8-8.5; and / or Optionally, the total concentration of the froth concentrate obtained from the roughing in the first cleaning process, after being adjusted with water, is 20 wt% to 30 wt%; and / or Optionally, in the first fine-tuning process, 60g-80g or 70g of titanium dioxide collector is added to each ton of frothy concentrate obtained from the roughing process; and / or Optionally, in the first fine-tuning process, 100g-300g or 200g of gangue inhibitor is added to every ton of frothy concentrate obtained from the roughing process; and / or Optionally, in the first fine-tuning process, 20g-40g or 30g of activator is added to each ton of frothy concentrate obtained from the roughing process; and / or Optionally, in the first fine treatment, the mass ratio of the frothy concentrate obtained from the roughing process to water is 20:80 to 30:70; and / or Optionally, in the first selection, the pH adjustment is to adjust the pH to 8-8.5; and / or Optionally, in the second refining process, the concentration of foam concentrate 3 after mixing with water is 20 wt% to 30 wt%; and / or Optionally, the gangue inhibitor in the first or second roughing process is carboxymethyl cellulose and sodium fluorosilicate; and / or Optionally, the gangue inhibitor in the first or second roughing process is carboxymethyl cellulose and sodium fluorosilicate in a mass ratio of 1:3 to 3:3 or 2:3; and / or Optionally, the titanium dioxide collector used in the first roughing, second roughing, or first cleaning is benzylarsine and sodium hydroxamic acid; and / or Optionally, the mass ratio of benzylarsonic acid and sodium hydroxamic acid in the titanium dioxide collectors obtained from the first roughing, second roughing, or first cleaning is independently selected from 1:2 to 1:4, or 1:2 or 2:5; and / or Optionally, the first selected gangue inhibitor is aluminum sulfate and starch; and / or Optionally, the first selected gangue inhibitor is aluminum sulfate and starch in a mass ratio of 2:1 to 1:2 or 1:1; and / or Optionally, the pH adjustment for the first coarse selection, the second coarse selection, or the first fine selection is performed using sodium carbonate.

6. The preparation method according to any one of claims 1 to 5, wherein the titanium-rich material in step (2) is ground to a particle size D90 of 38 micrometers to 75 micrometers; and / or The silicon powder in step (3) is ground to a particle size of less than or equal to 38 micrometers before being mixed with water.

7. The preparation method according to any one of claims 1 to 6, wherein the precipitation of solid A in step (2) includes precipitating solid A by heating, or adding seed crystals to the filtrate 1 after adding water and heating for hydrolysis to precipitate solid A; and / or In step (2), the operation of adding water to filtrate 1 and heating it for hydrolysis is performed in a mass ratio of filtrate 1 to water of 1:3-1:5 or 1:4; and / or In step (2), the temperature at which filtrate 1 is added to water and heated for hydrolysis is 80-90℃ or 90℃; and / or In step (2), the hydrolysis time for adding water and heating the filtrate 1 is 1 hour to 5 hours or 1 hour; and / or The concentration of the sodium hydroxide aqueous solution in step (2) is 10 mol / L to 15 mol / L or 10 mol / L; and / or In step (2), 80 ml to 120 ml of sodium hydroxide aqueous solution is added for every 1 g of TiO2 powder; and / or The temperature of the hydrothermal reaction in step (2) is 180℃~220℃, or 200℃; and / or The hydrothermal reaction time in step (2) is 24h to 30h; and / or The temperature for heating and hydrolysis in step (4) is 90℃~95℃; and / or The heating and hydrolysis time in step (4) is 3-4 hours; and / or In step (5), the adsorbent precursor TiO2-SiO2 and lithium carbonate are fed in a lithium:titanium molar ratio of 2:1 to 2.5:1; and / or The roasting temperature in step (5) is 600℃~700℃, or 600℃; and / or The roasting time in step (5) is 4h to 6h, or 4h; and / or The concentration of the hydrochloric acid aqueous solution in step (5) is 1 wt% to 2 wt%.

8. The preparation method according to claim 7, wherein the seed crystal is titanium dioxide or its hydrate; and / or The mass ratio of titanium in the seed crystal to titanium in filtrate 1 is 1:20 to 1:25; and / or The heating process for the precipitation of solid A involves heating to 90°C to 95°C.

9. A lithium adsorbent prepared by the preparation method according to any one of claims 1 to 8.

10. The application of the lithium adsorbent prepared by the preparation method according to any one of claims 1 to 8 or the lithium adsorbent according to claim 9 in the adsorption of lithium in salt lake brine.

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