A method for preparing a self-excited vanadium-based lithium-ion sieve

Abstract

This invention discloses a method for preparing a self-excited vanadium-based lithium-ion sieve. A vanadium source and a lithium source are mixed and calcined to prepare a vanadium-based composite A with lithium-ion channels. Composite A is then calcined again with an active agent to prepare a vanadium-based lithium-ion sieve precursor. Finally, the vanadium-based lithium-ion sieve precursor is fully reacted with a delithiating agent. After the reaction is complete, the mixture is washed, centrifuged, and dried to obtain a vanadium-based lithium-ion sieve with good selective lithium-ion adsorption capacity. This adsorbent lithium extraction process can directly utilize natural kinetic energy for self-excited lithium extraction in lithium-containing brine, without the need for additional industrial power. Therefore, this lithium extraction process is low-carbon and environmentally friendly, significantly reducing lithium extraction costs and offering significant economic benefits. It is of great significance for the development of difficult-to-mine salt lake lithium resources at high altitudes with poor industrial infrastructure.

Description

Technical Field

[0001] This invention belongs to the field of lithium extraction technology from salt lakes or underground lithium-containing brine, specifically relating to a method for preparing a self-excited vanadium-based lithium ion sieve. Background Technology

[0002] Lithium, as one of the most promising new energy resources of the 21st century, enjoys the high reputation of "white oil" and "energy star." Since its discovery by a Swedish chemist in the 19th century, when usable lithium resources were first isolated, it has been widely used in various familiar fields. With the advent of the new energy era, lithium is not only used as a thickener in lubricating grease products, but is also widely used in the battery field. Lithium batteries have significant advantages over other types of batteries, such as high capacity and long cycle life.

[0003] The main methods for lithium extraction from salt lake brine are: precipitation, membrane separation, extraction, electrochemical methods, calcination, and adsorption. Currently, precipitation, calcination, and adsorption are used in industrial production, but these methods all have certain problems when applied to lithium extraction from salt lakes in China. Among them, the calcination method involves first spray-drying the concentrated brine, then calcining the mixed salt powder at high temperature to convert MgCl2 into MgO, and finally leaching LiCl with water. This method is energy-intensive and costly, and has been gradually replaced by new technologies. Precipitation is suitable for salt lakes with low magnesium-to-lithium ratios. Membrane separation can be used for lithium extraction from salt lakes with high magnesium-to-lithium ratios, but it suffers from problems such as membrane clogging or damage and high cost of imported membrane materials. Extraction has high selectivity for lithium, but the use of large amounts of extractant causes equipment corrosion and environmental pollution. Electrochemical methods are environmentally friendly and efficient, but their mechanisms are not yet fully understood. Adsorption methods have advantages such as strong adaptability, simple process flow, and high selectivity, making them easy to industrialize. However, the main industrial applications currently use aluminum-based adsorbents, which have low adsorption capacity and can only be used for lithium extraction from old brine.

[0004] Given the limited availability of existing brine resources, developing lithium extraction technology from raw brine is of significant practical importance. This invention develops a self-excited vanadium-based lithium-ion sieve with kinetic energy response capability. Adding this sieve to raw brine in salt lakes allows for highly selective lithium extraction using natural kinetic energy. The process is simple, requires no external energy supply, is low-cost, and environmentally friendly. It is of great significance for accelerating lithium extraction from salt lake brine, alleviating the slow development of new energy sources, and overcoming development bottlenecks. Summary of the Invention

[0005] This invention provides a method for preparing a self-excited vanadium-based lithium-ion sieve. The process first uses a vanadium source and a lithium source to synthesize a vanadium-based composite A. Then, the composite A is calcined and combined with an active additive to obtain a vanadium-based lithium-ion sieve precursor. Finally, the vanadium-based lithium-ion sieve precursor is mixed and reacted with a delithiation agent. After delithiation is completed, a vanadium-based lithium-ion sieve with high selectivity for lithium ions is obtained. This lithium-ion sieve has been successfully applied to lithium extraction from salt lake brine.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A novel wave energy lithium extraction process using a self-excited vanadium-based lithium-ion sieve includes the following steps: I. Vanadium source and lithium source are mixed, ground and sieved, and then calcined to prepare vanadium-based composite A with lithium ion channels.

[0007] II. Prepare a vanadium-based lithium-ion sieve precursor by calcining composite A with an active additive.

[0008] III. Thoroughly mix and react the vanadium-based lithium-ion sieve precursor with a delithiation agent. The resulting solid after washing, centrifugation, and drying is the vanadium-based lithium-ion sieve.

[0009] IV. The prepared vanadium-based lithium ion sieve is uniformly dispersed in lithium-containing brine, which can achieve self-excited selective adsorption of lithium ions.

[0010] V. The vanadium-based lithium-ion sieve that has completed adsorption in step IV is delithiated in step III and recycled for reuse.

[0011] In the self-excited vanadium-based lithium-ion sieve preparation method described above, preferably, the vanadium source particle size used in step I is 200-800 mesh.

[0012] In the self-excited vanadium-based lithium-ion sieve preparation method described above, preferably, the mass ratio of vanadium source to lithium source used in step I is 1:(0.5-3).

[0013] In the above-described method for preparing a self-excited vanadium-based lithium-ion sieve, preferably, the vanadium source used in step I is one or a mixture of two or more of vanadium monoxide, vanadium dioxide, vanadium pentoxide, vanadium carbonate, vanadium oxalate, vanadium sulfate, ammonium vanadate, vanadium hydroxide, ammonium metavanadate, vanadium oxysulfate, vanadium oxalate, vanadium tetrachloride, and vanadium oxychloride.

[0014] In the self-excited vanadium-based lithium-ion sieve preparation method described above, preferably, the lithium source used in step I is one or a mixture of two or more of lithium carbonate, lithium nitrate, lithium chloride, lithium sulfate, lithium silicate, lithium phosphate, lithium acetate, lithium oxalate, or lithium hydroxide.

[0015] In the method for preparing a self-excited vanadium-based lithium-ion sieve as described above, preferably, in step I, the calcination temperature is 400–800°C and the calcination time is 2.5–8 hours.

[0016] In the above-described method for preparing a self-excited vanadium-based lithium-ion sieve, preferably, the active agent in step II is one or a mixture of two or more of barium titanate, niobium tantalate, potassium niobate, sodium bismuth titanate, lithium gallate, lithium germanate, titanium germanate, bismuth borate, and zinc oxide.

[0017] In the above-described method for preparing a self-excited vanadium-based lithium-ion sieve, preferably, the mass ratio of complex A to active additive in step II is 1:(0.5-5).

[0018] In the above-described method for preparing a self-excited vanadium-based lithium-ion sieve, preferably, in step II, the calcination temperature is 300–500°C and the calcination time is 1–8 h.

[0019] In the above-described method for preparing a self-excited vanadium-based lithium-ion sieve, preferably, the delithiation agent used in step III is one or a mixture of two or more of sodium persulfate, potassium persulfate, oxalic acid, citric acid, hydrogen peroxide, nitric acid, sodium hypochlorite, hydrochloric acid, sulfuric acid, and acetic acid.

[0020] In the self-excited vanadium-based lithium ion sieve preparation method described above, the vanadium-based lithium ion sieve that adsorbs lithium ions in step IV can be delithiated in step III and recycled. Attached Figure Description

[0021] Figure 1 This is a simplified process flow diagram of the present invention.

[0022] Figure 2 XRD pattern of vanadium-based lithium-ion sieve provided in Embodiment 1 of the present invention. Detailed Implementation

[0023] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the invention. Example

[0024] In Example 1, the vanadium source used was vanadium pentoxide with a particle size between 200 and 300 mesh. It was calcined with lithium phosphate (particle size between 200 and 300 mesh) at a mass ratio of 1:2 in a tube furnace at 600°C for 2 hours to obtain a vanadium-based composite with lithium-ion channels. Then, this composite was calcined with barium titanate at a mass ratio of 1:3 in a tube furnace at 300°C for 4 hours to obtain a vanadium-based lithium-ion sieve precursor. Finally, the vanadium-based lithium-ion sieve precursor was mixed with sodium persulfate and reacted. After the reaction was complete, the solid was washed multiple times with deionized water. This step aimed to thoroughly remove the Li+ adhering to the vanadium-based lithium-ion sieve. + Then the desorption of Li will be completed.+ The vanadium-based lithium ion sieve was then placed in the raw brine of Yiliping Salt Lake in Qinghai. After 7 days in the brine, the vanadium-based lithium ion sieve could adsorb up to 9.5 mg / g of lithium ions.

[0025] The chemical composition of the original brine of Yiliping Salt Lake is shown in Table 1.

[0026]

[0027] Table 1. Chemical composition of raw brine in Yiliping Salt Lake (g / L) Example

[0028] In Example 2, vanadium hydrogen phosphate and lithium carbonate were thoroughly ground and mixed at a mass ratio of 1:1. The mixture was then calcined in a tube furnace at 400°C for 6 hours under an argon atmosphere to obtain a vanadium-based composite with lithium-ion channels. This composite was then calcined with sodium bismuth titanate at a mass ratio of 1:1 in a tube furnace at 500°C for 4 hours to obtain a vanadium-based lithium-ion sieve precursor. This precursor was then reacted with hydrogen peroxide solution, centrifuged, and dried to obtain a vanadium-based lithium-ion sieve. Finally, the desorbed Li... + The vanadium-based lithium ion sieve was then placed into the original brine of the Xitaijinaier Salt Lake.

[0029] The chemical composition of the brine in the Xitaijinaier Salt Lake in the Qaidam Basin of Qinghai Province is shown in Table 2. The vanadium-based lithium-ion sieve showed an adsorption capacity of up to 9 mg / g of lithium in the salt lake after 5 days.

[0030] Table 2 Chemical composition of raw brine in Xitaijinaier Salt Lake (g / L)

[0031] Example 3 Example 3: Vanadium dihydrogen phosphate and lithium hydroxide were uniformly dispersed in anhydrous ethanol solution at a mass ratio of 1:1 and thoroughly mixed. The mixture was then calcined in a tube furnace at 500°C for 5 hours in the absence of oxygen to obtain a vanadium-based composite with lithium-ion channels. This composite was then calcined with zinc oxide in a tube furnace at a mass ratio of 1:2 at 300°C for 6 hours in the absence of oxygen to obtain a vanadium-based lithium-ion sieve precursor. This vanadium-based lithium-ion sieve precursor was reacted with potassium persulfate solution. After the reaction was completed, the precursor was centrifuged and dried to obtain a vanadium-based lithium-ion sieve. The desorbed Li... + The vanadium-based lithium ion sieve was then placed into the original brine of the salt lake.

[0032] The salt lake involved in this embodiment is the Dongtaijinaier Salt Lake in the Qaidam Basin of Qinghai Province, and its brine chemical composition is shown in Table 3. The vanadium-based lithium ion sieve can adsorb up to 10.2 mg / g of lithium in this salt lake after 10 days.

[0033] Table 3 Chemical composition of raw brine in Dongtai Jinaier Salt Lake (g / L)

[0034] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for preparing a self-excited vanadium-based lithium-ion sieve, characterized in that, The method includes the following steps: I. A vanadium-based composite A with lithium-ion channels is prepared by mixing vanadium source and lithium source, grinding and sieving, and then calcining. The calcination temperature is 300-900℃ and the calcination time is 0.5h-24h. II. A vanadium-based lithium-ion sieve precursor is prepared by calcining composite A with an active additive, wherein the calcination temperature is 200–600℃ and the calcination time is 0.5 h–12 h. The active additive is one or a mixture of two or more of the following: barium titanate, niobium tantalate, potassium niobate, sodium bismuth titanate, lead titanate, lead zirconate titanate, lithium gallium oxide, lithium germanate, titanium germanate, lead barium lithium titanate, bismuth borate, zirconium oxide, and zinc oxide. III. Thoroughly mix and react the vanadium-based lithium-ion sieve precursor with a delithiation agent. The solid obtained after washing, centrifugation, and drying is the vanadium-based lithium-ion sieve. IV. The prepared vanadium-based lithium ion sieve is uniformly dispersed in lithium-containing brine to achieve self-excited selective adsorption of lithium ions; V. The vanadium-based lithium-ion sieve that has completed adsorption in step IV is delithiated in step III and recycled for reuse.

2. The method for preparing a self-excited vanadium-based lithium-ion sieve according to claim 1, characterized in that, The vanadium source used in step I has a particle size of 100-1000 mesh.

3. The method for preparing a self-excited vanadium-based lithium-ion sieve according to claim 1, characterized in that, The mass ratio of vanadium source to lithium source used in step I is 1:(0.5-5).

4. The method for preparing a self-excited vanadium-based lithium-ion sieve according to claim 1, characterized in that, The vanadium source used in step I is one or a mixture of two or more of the following: vanadium monoxide, vanadium dioxide, vanadium trioxide, vanadium pentoxide, vanadium heptaoxide, vanadium carbonate, vanadium oxalate, vanadium phosphate, vanadium sulfate, ammonium vanadate, sodium vanadate, bismuth vanadate, zinc vanadate, vanadium hydroxide, ammonium metavanadate, sodium metavanadate, potassium metavanadate, sodium orthovanadate, ammonium orthovanadate, potassium orthovanadate, vanadium oxysulfate, vanadium oxalate, vanadium tetrachloride, and vanadium oxytrichlorochloride.

5. The method for preparing a self-excited vanadium-based lithium-ion sieve according to claim 1, characterized in that, The lithium source used in step I is one or a mixture of two or more of the following: lithium carbonate, lithium bicarbonate, lithium nitrate, lithium chloride, lithium sulfate, lithium silicate, lithium phosphate, lithium acetate, lithium oxalate, or lithium hydroxide.

6. The method for preparing a self-excited vanadium-based lithium-ion sieve according to claim 1, characterized in that, In step II, the mass ratio of complex A to active adjuvant is 1:(0.3-8).

7. The method for preparing a self-excited vanadium-based lithium-ion sieve according to claim 1, characterized in that, The delithiation agent used in step III is one or a mixture of two or more of the following: sodium persulfate, potassium persulfate, calcium persulfate, magnesium persulfate, citric acid, oxalic acid, hydrogen peroxide, nitric acid, sodium hypochlorite, potassium hypochlorite, calcium hypochlorite, hydrochloric acid, sulfuric acid, acetic acid, or a combination of two or more of the above.

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