Patent Application
20230212714
This application is based on and claims priority to and benefits of Chinese Patent Application No. 202111682549.X, filed on Dec. 31, 2021. The entire content of the above-referenced application is incorporated herein by reference.
The present disclosure relates to the technical field of lithium extraction process from brine or seawater, and specifically, to a lithium extraction apparatus and a lithium extraction method.
Lithium plays an important role in the electronic, metallurgy, chemical, medicine and other fields. Lithium in nature mainly exists in lithium ores, salt lake brine, seawater and geothermal water. The lithium content in salt lake brine is the highest, accounting for 66% of the world's lithium reserves and more than 80% of the basic lithium reserve.
Existing lithium extraction methods from brine include precipitation, calcination-leaching, solvent extraction, membrane separation, and adsorption. Adsorption has the advantages of simple process, environmental protection and so on. However, there are many problems in the existing adsorption method, such as too much production equipment, a complex process, a low utilization rate of adsorbent, a high production cost and a low lithium extraction rate, which reduce the resource utilization and are not conducive to the development of the new energy industry.
To solve the above problems, the present disclosure provides a lithium extraction apparatus, which greatly improves the utilization of adsorbent through layered reactions, thereby increasing the extraction rate of lithium. The apparatus is simple, and has a high degree of automation, and a low production cost, which are beneficial to its use in the extraction of lithium from brine.
In a first aspect, the present disclosure provides a lithium extraction apparatus, which includes a frame and a transmission mesh belt installed on the frame. The transmission mesh belt includes water permeable holes, and is configured to carry an adsorbent. The frame includes an adsorption zone and a desorption zone along a traveling direction of the transmission mesh belt. A brine spraying device is disposed above the transmission mesh belt in the adsorption zone. A desorbing liquid spraying device is disposed above the transmission mesh belt in the desorption zone. A lithium extract collecting device is disposed below the transmission mesh belt in the desorption zone.
The transmission mesh belt in the adsorption zone is folded into a multi-layer structure in the vertical direction, an input end of the transmission mesh belt in the adsorption zone is far away from the brine spraying device, and an output end of the transmission mesh belt in the adsorption zone is close to the brine spraying device; and/or
the transmission mesh belt in the desorption zone is folded into a multi-layer structure in the vertical direction, an input end of the transmission mesh belt in the desorption zone is far away from the desorbing liquid spraying device, and an output end of the transmission mesh belt in the desorption zone is close to the desorbing liquid spraying device.
In some embodiments of the present disclosure, in the adsorption zone, a layer number of the multi-layer structure is 2 to 8.
In some embodiments of the present disclosure, in the desorption zone, a layer number of the multi-layer structure is 2 to 8.
In some embodiments of the present disclosure, the transmission mesh belt includes a baffle mechanism that turns the flow of the liquid therein, and the baffle mechanism includes an internal space for accommodating the adsorbent.
In some embodiments of the present disclosure, the lithium extraction apparatus further includes a water permeable filter detachably connected to a surface of the transmission mesh belt.
In some embodiments of the present disclosure, the brine spraying device includes a nozzle, including a sprinkling nozzle and a jet nozzle.
In some embodiments of the present disclosure, the desorbing liquid spraying device includes a nozzle, including a sprinkling nozzle and a jet nozzle.
In some embodiments of the present disclosure, a brine collecting device is disposed below the transmission mesh belt in the adsorption zone.
In some embodiments of the present disclosure, the frame includes a rinsing zone along the traveling direction of the transmission mesh belt, where the rinsing zone is located between the adsorption zone and the desorption zone, and a rinsing liquid spraying device is disposed above the transmission mesh belt in the rinsing zone.
In some embodiments of the present disclosure, a rinsing liquid collecting device is disposed below the transmission mesh belt in the rinsing zone.
In some embodiments of the present disclosure, the frame includes a regeneration zone, where an input end of the transmission mesh belt in the regeneration zone corresponds to the output end of the transmission mesh belt in the desorption zone, an output end of the transmission mesh belt in the regeneration zone corresponds to the input end of the transmission mesh belt in the adsorption zone, and a regeneration liquid spraying device is disposed above the transmission mesh belt in the regeneration zone.
In some embodiments of the present disclosure, a regeneration liquid collecting device is disposed below the transmission mesh belt in the regeneration zone.
The lithium extraction apparatus provided in the first aspect of the present disclosure can effectively improve the adsorption and/or desorption efficiency of an adsorbent through layered reactions, thus reducing the lithium extraction time. Moreover, the apparatus is simple, with small floor space, and has a high degree of automation, which facilitates the wide scope of use.
In a second aspect, the present disclosure provides a lithium extraction method, using the lithium extraction apparatus as described in the first aspect. The method includes moving the transmission mesh belt to contact the adsorbent with brine in the adsorption zone to obtain a lithium containing adsorbent; and to contact the lithium containing adsorbent with a desorbing liquid in the desorption zone to obtain a lithium extract.
In some embodiments of the present disclosure, a weight of lithium ions adsorbed by per gram of the adsorbent per hour is greater than or equal to 9 mg.
In some embodiments of the present disclosure, a weight of lithium ions desorbed from per gram of the lithium containing adsorbent per hour is greater than or equal to 9 mg.
In some embodiments of the present disclosure, the adsorbent includes one or more of a manganese-based lithium ion sieve and a titanium-based lithium ion sieve.
In some embodiments of the present disclosure, an average particle size of the adsorbent is 200 μm to 1 mm.
In some embodiments of the present disclosure, the desorbing liquid includes an inorganic acid solution.
In some embodiments of the present disclosure, the desorbing liquid further includes potassium ferrate.
In some embodiments of the present disclosure, the desorbing liquid further includes a hypochlorite.
In some embodiments of the present disclosure, the desorbing liquid includes a hypochlorite, potassium ferrate, and an inorganic acid, where a concentration of potassium ferrate is 1 g/L to 10 g/L, a concentration of the hypochlorite is 1 g/L to 10 g/L, and a concentration of the inorganic acid is 3 g/L to 20 g/L.
transmission mesh belt 1, water permeable filter 11, baffle mechanism 12, frame 2, adsorption zone 21, brine spraying device 211, brine collecting device 212, desorption zone 22, desorbing liquid spraying device 221, lithium extract collecting device 222, rinsing zone 23, rinsing liquid spraying device 231, rinsing liquid collecting device 232, regeneration zone 24, regeneration liquid spraying device 241, and regeneration liquid collecting device 242.
The technical solutions in embodiments of the present disclosure are clearly and completely described below with reference to the accompanying drawings in the embodiments of the present disclosure. Apparently, the embodiments to be described are merely some rather than all of the embodiments of the present disclosure. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.
At present, to ensure that the adsorbent is fully contacted with the brine, a column separation method or stirring method is often used in the existing process of extracting lithium by adsorption. The column separation method is to feed the brine into an adsorption column filled with an adsorbent, and then rinse and desorb the adsorption column. The stirring method is to stir the brine and the adsorbent together, then filter out the adsorbent, and rinse and desorb the adsorbent. The above methods require many pieces of equipment, and have a complex process, a high production cost, a low utilization of the adsorbent, limited extraction of lithium in brine, and an excessive resource consumption being not conducive to the development of the industry. Therefore, the present disclosure provides a lithium extraction apparatus, in which a transmission mesh belt is designed to have a multi-layer structure to enable the repeated use of the adsorbent, thereby improving the utilization rate of the adsorbent and the extraction rate of lithium, and greatly reducing the cost of the product. The present disclosure promotes the development of the lithium extraction process in the industry.
In some embodiments of the present disclosure, a brine collecting device 212 is provided below the transmission mesh belt in the adsorption zone 21. The brine collecting device is used to collect the post-adsorption liquid flowing out of the transmission mesh belt in the adsorption zone, where the collected post-adsorption liquid can be returned to the brine collecting device for secondary extraction or recovery of other materials, to enhance the resource utilization. In some embodiments of the present disclosure, an output end of the transmission mesh belt in the desorption zone corresponds to the input end of the transmission mesh belt in adsorption zone. Lithium ions in the lithium containing adsorbent can be removed in the desorption zone, and the lithium containing adsorbent can be used to adsorb lithium ions again, that is, the lithium containing adsorbent is regenerated into an adsorbent. The regenerated adsorbent can move together with the transmission mesh belt to the adsorption zone of the lithium extraction apparatus, to realize the recycled use.
In the present disclosure, for the purpose of improving the utilization of adsorbent to allow the adsorbent to fully adsorb the lithium ions in the brine or the desorbing liquid to fully elute the lithium ions in the lithium containing adsorbent, the transmission mesh belt in the lithium extraction apparatus is provided with a multi-layer structure. In some embodiments, the transmission mesh belt in the adsorption zone is folded into a multi-layer structure in the vertical direction.
For the adsorbent, an input end of the first adsorption layer is the input end of the transmission mesh belt in the adsorption zone, and an output end of the third adsorption layer is the output end of the transmission mesh belt in the adsorption zone. It can be understood that a small number of lithium ions are adsorbed by the adsorbent in the first adsorption layer, and a large number of lithium ions are adsorbed by the adsorbent in the third adsorption layer. Therefore, the adsorbent in the first adsorption layer has a high adsorption capacity for lithium ions, the adsorption capacity of the adsorbent in the second adsorption layer is smaller than that of the adsorbent in the first adsorption layer, and the adsorption capacity of the adsorbent in the third adsorption layer is smaller than that of the adsorbent in the second adsorption layer. Since the adsorption capacity of the adsorbent gradually decreases from the first adsorption layer to the third adsorption layer, the adsorption efficiency of the adsorbent from the first adsorption layer to the third adsorption layer becomes lower for the same concentration of brine. Therefore, to maintain a high adsorption efficiency, the concentration of brine needs to be increased.
For the brine, the brine first flows to the transmission mesh belt in the adsorption zone closest to the brine spraying device, that is, the third adsorption layer. After the adsorbent in the third adsorption layer adsorbs lithium ions in brine, the concentration of lithium ions in brine is reduced. The brine in the third adsorption layer flows downward under the action of gravity, and flows out from the water permeable holes of the transmission mesh belt and to the second adsorption layer. After the brine is adsorbed by the adsorbent in the second adsorption layer, the concentration of lithium ions is reduced again. Then the brine flows to the first adsorption layer. After the brine is adsorbed in the first adsorption layer, lithium in the brine is extracted mostly, and the remaining post-adsorption liquid flows out from the first adsorption layer and into the brine collecting device. It can be understood that during the lithium extraction process, the concentration of brine in the third adsorption layer is greater than the concentration of brine in the second adsorption layer, which is greater than the concentration of brine in the first adsorption layer.
During the operation of the lithium extraction apparatus, the adsorbent in the first adsorption layer has a high adsorption capacity, and the brine adsorbed by the adsorbent in the first adsorption layer has a low lithium ion concentration that has been absorbed by the preceding two adsorption layers, so the adsorbent can fully extract lithium ions in brine, thus greatly reducing the concentration of lithium ions in the post-adsorption liquid. The adsorbent in the first adsorption layer will move to the second adsorption layer with the movement of the transmission mesh belt. The concentration of brine in the second adsorption layer is higher than that in the first adsorption layer, so the adsorbent can continue to adsorb lithium ions. After adsorbing lithium ions in the brine, the adsorbent in the second adsorption layer further moves to the third adsorption layer with the transmission mesh belt and adsorbs the brine in the third adsorption layer. After the adsorption by the adsorbent in the third adsorption layer is completed, it moves away from the adsorption zone with the movement of the transmission mesh belt.
As can be seen, in the lithium extraction apparatus of the present disclosure, the transmission mesh belt in the adsorption zone is arranged to have a multi-layer structure, to achieve the multiple adsorptions by the adsorbent, thereby greatly improving the utilization rate of the adsorbent, and allowing the adsorbent to absorb as much lithium ions in the brine as possible. Thus, the extraction rate of lithium in the brine is improved.
In some embodiments of the present disclosure, a layer number of the multi-layer structure of the transmission mesh belt in the adsorption zone is 2 to 8. In the adsorption zone, the multi-layer structure includes, but not limited to, 2, 3, 4, 5, 6, 7 or 8 layers. A schematic structural diagram of a transmission mesh belt with a 2-layer structure in the adsorption zone is shown in
In some embodiments of the present disclosure, the distance between layers in the adsorption zone is from 0.05 m to 0.3 m. When the distance between layers of the multi-layer mesh belt is configured within the range of 0.05 m to 0.3 m, the flow rate of brine between layers is moderate to facilitate the brine to penetrate into the adsorbent evenly, and the apparatus can also operate efficiently.
In an embodiment of the present disclosure, a lithium containing adsorbent is obtained after the adsorbent adsorbs lithium ions in the adsorption zone, and then the lithium containing adsorbent moves to the desorption zone with the transmission mesh belt, where the desorbing liquid is brought into contact with the lithium containing adsorbent to elute off lithium ions in the lithium containing adsorbent. The lithium ions enter the desorbing liquid, to obtain a lithium extract. The lithium extract then flows into the lithium extract collecting device through the water permeable holes of the transmission mesh belt. To improve the desorption efficiency of the lithium containing adsorbent in the desorption zone, in some embodiments of the present disclosure, the transmission mesh belt in the desorption zone is vertically folded into a multi-layer structure.
For the lithium containing adsorbent, an input end of the first desorption layer is the input end of the transmission mesh belt in the desorption zone, and an output end of the third desorption layer is the output end of the transmission mesh belt in the desorption zone. It can be understood that a large number of lithium ions are adsorbed by the lithium containing adsorbent in the first desorption layer; and a small number of lithium ions are adsorbed by the lithium containing adsorbent in third desorption layer, so the lithium ions in the lithium containing adsorbent in the first desorption layer are easy to be eluted off, and the lithium containing adsorbent has a high desorption capacity. The desorption capacity of the lithium containing adsorbent in the second desorption layer is smaller than that of the lithium containing adsorbent in the first desorption layer, and the desorption capacity of the lithium containing adsorbent in the third desorption layer is smaller than that of the lithium containing adsorbent in the second desorption layer. Since the desorption capacity of the lithium containing adsorbent gradually decreases from the first desorption layer to the third desorption layer, the desorption efficiency of the lithium containing adsorbent from the first desorption layer to the third desorption layer becomes lower for the same concentration of desorbing liquid. Therefore, to maintain a high desorption efficiency, the concentration of the desorbing liquid needs to be increased.
For the desorbing liquid, the desorbing liquid first flows to the transmission mesh belt closest to the desorbing liquid spraying device in the desorption zone, that is, the third desorption layer. After the lithium ions in the lithium containing adsorbent is displaced under the action of the desorbing liquid in the third desorption layer, the concentration of hydrogen ions in the desorbing liquid decreases, and the concentration of lithium ions increases. The desorbing liquid in the third desorption layer flows downward under the action of gravity, and flows out from the water permeable holes of the transmission mesh belt and to the second desorption layer. After the desorbing liquid interacts with the lithium containing adsorbent in the second desorption layer, the concentration of hydrogen ions in the desorbing liquid further decreases, and the concentration of lithium ions increases again. Then, the desorbing liquid flows to the first desorption layer, and the lithium containing adsorbent in the first desorption layer is desorbed under the action of the desorbing liquid. After the desorption by the desorbing liquid in first desorption layer is completed, a lithium extract is obtained. The lithium extract then flows into the lithium extract collecting device through the water permeable holes of the transmission mesh belt. It can be understood that during the lithium extraction process, the hydrogen ion concentration in the desorbing liquid in the third desorption layer is greater than the hydrogen ion concentration in the desorbing liquid in the second desorption layer, which is greater than the hydrogen ion concentration in the desorbing liquid in the first desorption layer.
During the operation of the lithium extraction apparatus, due to the high lithium content in the lithium containing adsorbent in the first desorption layer, the lithium ions can be easily eluted off. The desorbing liquid in the first desorption layer has passed through the previous two desorption zones, so the concentration of hydrogen ions in the desorbing liquid is low. The desorbing liquid can preliminarily extract the lithium ions in the lithium containing adsorbent. The lithium containing adsorbent in the first desorption layer moves to the second desorption layer with the movement of the transmission mesh belt. The concentration of hydrogen ions in the desorbing liquid in the second desorption layer is higher than that in the first desorption layer, so the lithium ions in the lithium containing adsorbent are further displaced, and the desorption capacity of the lithium containing adsorbent decreases. The lithium containing adsorbent in the second desorption layer then moves to the third desorption layer with the movement of the transmission mesh belt. The lithium containing adsorbent in the third desorption layer has a lowest desorption capacity; however, the desorbing liquid in the third desorption layer has a larger hydrogen ion concentration. The desorbing liquid has a strong capacity to displace lithium ions in the lithium containing adsorbent, thereby greatly reducing the remaining lithium in the lithium containing adsorbent, and achieving the sufficient extraction of lithium. After the desorption of the lithium containing adsorbent in the third desorption layer is completed, the regeneration is accomplished, that is, the lithium containing adsorbent is regenerated into an adsorbent. The regenerated adsorbent moves away from the desorption zone with the movement of the transmission mesh belt.
As can be seen, in the lithium extraction apparatus of the present disclosure, the transmission mesh belt in the desorption zone is arranged to have a multi-layer structure, to achieve the multiple desorption of the lithium containing adsorbent, thereby greatly improving the utilization of the desorbing liquid and the adsorbent and eluting the lithium ions in the lithium containing adsorbent off into the desorbing liquid as much as possible. In this way, the lithium ions in the lithium containing adsorbent is fully extracted, and the lithium ion concentration in the lithium extract is increased. Moreover, the structure can also reduce the amounts of the desorbing liquid and the adsorbent, decrease the desorption time, and lower the manufacturing cost.
In some embodiments of the present disclosure, the transmission mesh belt in the desorption zone is vertically folded into a multi-layer structure, and a layer number of the multi-layer structure in the desorption zone is 2 to 8. In the desorption zone, the multi-layer structure includes, but not limited to, 2, 3, 4, 5, 6, 7 or 8 layers. When the number of layers of the transmission mesh belt in the desorption zone is configured within the above range, the efficiency of desorbing lithium ions from the lithium containing adsorbent in the desorption zone is high, the apparatus can operate with low energy consumption and a high efficiency, and the production cost of the apparatus is low. In some embodiments of the present disclosure, the multi-layer structure of the transmission mesh belt in the desorption zone includes 3 to 6 layers. It is to be noted that in the present disclosure, the transmission mesh belt in the desorption zone refers to the transmission mesh belt located between the desorbing liquid spraying device and the lithium extract collecting device.
In some embodiments of the present disclosure, the distance between layers in the desorption zone is from 0.05 m to 0.3 m. When the distance between layers of the multi-layer mesh belt in the desorption zone is configured within the range of 0.05 m to 0.3 m, the flow rate of the desorbing liquid between layers is moderate, to facilitate the desorbing liquid to penetrate into the lithium containing adsorbent evenly, and the apparatus can also operate efficiently.
In some embodiments of the present disclosure, the transmission mesh belt in the adsorption zone is folded into a multi-layer structure in the vertical direction, where an input end of the transmission mesh belt in the adsorption zone is far away from the brine spraying device, and an output end of the transmission mesh belt in the adsorption zone is close the brine spraying device; and the transmission mesh belt in the desorption zone is vertically folded into a multi-layer structure, where an input end of the transmission mesh belt in the desorption zone is far away from the desorbing liquid spraying device, and an output end of the transmission mesh belt in the desorption zone is close to the desorbing liquid spraying device.
In some embodiments of the present disclosure, the frame is also provided with a rinsing zone along the traveling direction of the transmission mesh belt, where the rinsing zone is located between the adsorption zone and desorption zone, and a rinsing liquid spraying device is provided above the transmission mesh belt in the rinsing zone. In some embodiments of the present disclosure, a rinsing liquid collecting device is provided below the transmission mesh belt in the rinsing zone. In some embodiments of the present disclosure, the rising liquid includes water. During the operation of the lithium extraction apparatus, the adsorbent is in contact with the brine, and some impurities in the brine will also adhere to the adsorbent surface. The arrangement of the rinsing zone can remove the impurities in the absorbent before lithium in the lithium containing adsorbent is extracted, so that the impurity content in the lithium extract obtained in the subsequent desorption process is reduced.
In some embodiments of the present disclosure, the rinsing zone includes multiple rinsing sections arranged in sequence along the traveling direction of the transmission mesh belt. A rinsing liquid spraying device is arranged above the transmission mesh belt in each rising section, and a rinsing liquid collecting device is provided below the transmission mesh belt in each rising section. In adjacent rising sections, a rinsing liquid collecting device located in a downstream rinsing section is communicated with a rinsing liquid spraying device located in an upstream rinsing section. That is, the rising liquid used in the upstream rinsing section is a liquid recovered after rinsing in the downstream rinsing section. In some embodiments, the rinsing zone includes a first rinsing section, a second rinsing section and a third rinsing section arranged in sequence along the traveling direction of the transmission mesh belt. The third rinsing section is close to the desorption zone, where water is used as a rising liquid in the third rinsing section, a first washing effluent is collected by the rinsing liquid collecting device in the third rinsing section, and the first washing effluent flows to the rinsing liquid spraying device in the second rinsing section. The first washing effluent is used as a rising liquid in the second rinsing section, a second washing effluent is collected by the rinsing liquid collecting device in the second rinsing section, and the second washing effluent flows to the rinsing liquid spraying device in the first rinsing section. The second washing effluent is used as a rising liquid in the first rinsing section. With such a gradient design, along the traveling direction of the transmission mesh belt, the lithium containing adsorbent is brought into contact with the rinsing liquids with less and less impurity content, and the washing effect is becoming better and better, so as to effectively remove the impurities in the lithium containing adsorbent, and save water.
In some embodiments of the present disclosure, the working area further includes a regeneration zone, where an input end of the transmission mesh belt in the regeneration zone corresponds to the output end of the transmission mesh belt in the desorption zone, an output end of the transmission mesh belt in the regeneration zone corresponds to the input end of the transmission mesh belt in the adsorption zone, and a regeneration liquid spraying device is provided above the transmission mesh belt in the regeneration zone. The lithium containing adsorbent is brought into contact with the desorbing liquid in the desorption zone, and the lithium ions in the lithium containing adsorbent is replaced by the hydrogen ions in the desorbing liquid, to achieve the lithium extraction. The lithium containing adsorbent can be used to adsorb lithium ions after removing the lithium ions, that is, the lithium containing adsorbent is regenerated into an adsorbent. After the regenerated adsorbent moves away from the desorption zone with the transmission mesh belt, there will be more hydrogen ions left in the regenerated adsorbent. A too high acidity of the regenerated adsorbent may affect the adsorption effect of the regenerated adsorbent for brine, which is not conducive to the reuse of the adsorbent. In the present disclosure, the hydrogen ions in the regenerated adsorbent can be diluted or neutralized by setting the regeneration zone at the output end of the desorption zone, which contributes to the regeneration of the adsorbent, and ensures that the regenerated adsorbent can be effectively used by fully absorbing lithium ions. In some embodiments of the present disclosure, a regeneration liquid collecting device is further provided below the transmission mesh belt in the regeneration zone. In some embodiments of the present disclosure, the regeneration liquid includes at least one of water or a basic solution.
In some embodiments of the present disclosure, the regeneration zone is provided after the desorption zone, that is, the regeneration zone is located at the side of the desorption zone away from the adsorption zone.
In some embodiments of the present disclosure, the lithium extraction apparatus further includes a water permeable filter detachably fixed to a surface of the transmission mesh belt. The water permeable filter is used to fix the adsorbent to the surface of the transmission mesh belt. In some embodiments, the water permeable filter is covered on the upper and lower surfaces of the transmission mesh belt, and the adsorbent is filled in the water permeable filter. In some embodiments, the water permeable filter is of a mesh bag structure, the adsorbent is accommodated in the water permeable filter, and then the water permeable filter is fixed to the surface of the transmission mesh belt.
In some embodiments of the present disclosure, the transmission mesh belt is provided with a baffle mechanism that can turn the flow of the liquid therein, and the baffle mechanism is provided with an internal space for accommodating the adsorbent.
In the lithium extraction apparatus provided in the present disclosure, the transmission mesh belt in the adsorption zone and/or the desorption zone is designed to have a multi-layer structure, the efficiency of the adsorbent adsorbing lithium ions and/or the lithium containing adsorbent desorbing lithium ions is greatly improved, thereby shortening the time of the lithium extraction process. The apparatus is simple in structure, with small floor space, which facilitates the wide scope of the use.
The present disclosure provides a lithium extraction method using a lithium extraction apparatus of the present disclosure. The method includes:
moving the transmission mesh belt, to contact the adsorbent with brine in the adsorption zone to obtain a lithium containing adsorbent, and then to contact the lithium containing adsorbent with a desorbing liquid in the desorption zone to obtain a lithium extract.
In some embodiments of the present disclosure, the weight of lithium ions adsorbed by per gram of the adsorbent per hour is greater than or equal to 9 mg. That is, the rate of the adsorbent adsorbing lithium ions is greater than or equal to 9 mg/g/h. The rate of the adsorbent adsorbing lithium ions can be, but not limited to, 9 mg/g/h, 12 mg/g/h, 15 mg/g/h, 20 mg/g/h, 30 mg/g/h, or 50 mg/g/h. With increasing rate of the adsorbent adsorbing lithium ions, the time for the adsorbent to adsorb lithium ions from the brine is reduced, more brine can be processed per unit time, the greater amount of lithium extracted is achieved, and more conducive to the improvement of the production efficiency. In some embodiments of the present disclosure, the weight of lithium ions desorbed from per gram of the lithium containing adsorbent per hour is greater than or equal to 9 mg. That is, the rate of the lithium containing adsorbent desorbing lithium ions is greater than or equal to 9 mg/g/h. The rate of the lithium containing adsorbent desorbing lithium ions can be, but not limited to, 9 mg/g/h, 12 mg/g/h, 15 mg/g/h, 20 mg/g/h, 30 mg/g/h, or 50 mg/g/h. With increasing rate of the lithium containing adsorbent desorbing lithium ions, the time for desorbing lithium ions from the lithium containing adsorbent is reduced, more lithium extract can be obtained per unit time, the greater amount of lithium extracted is achieved, and more conducive to the improvement of the production efficiency.
In some embodiments of the present disclosure, the adsorbent includes one or more of a manganese-based lithium ion sieve and a titanium-based lithium ion sieve. The manganese-based lithium ion sieve and titanium-based lithium ion sieve have high adsorption and desorption rates, and short adsorption and desorption time, thus shortening the production time. In some embodiments of the present disclosure, the adsorbent includes a metatitanate-type lithium ion sieve adsorbent. In some embodiments of the present disclosure, the adsorbent includes a spinel-type manganese oxide. The spinel-type manganese oxide has a good selectivity for lithium ions, thus reducing the content of impurities in the lithium extract, and improving the extraction rate of lithium.
In an embodiment of the present disclosure, the desorbing liquid includes an acid solution, which may be an organic acid solution, or an inorganic acid solution. In some embodiments of the present disclosure, the desorbing liquid includes an inorganic acid, including one or more of sulfuric acid, hydrochloric acid, and nitric acid. In some embodiments of the present disclosure, the concentration of the inorganic acid in the desorbing liquid is 3 g/L-20 g/L. The concentration of the inorganic acid in the desorbing liquid can be, but not limited to, 3 g/L, 5 g/L, 8 g/L, 10 g/L, 13 g/L, 15 g/L, or 20 g/L.
In some embodiments of the present disclosure, the adsorbent includes a manganese-based lithium ion sieve, and the desorbing liquid includes an acid solution and potassium ferrate. Potassium ferrate has a strong oxidizability, and can inhibit the disproportionation reaction of tetravalent manganese ions in the manganese-based lithium ion sieve, thus reducing the dissolution loss of manganese, and improving the cycle performance and service life of the adsorbent. In some embodiments of the present disclosure, the concentration of potassium ferrate in the desorbing liquid is 1 g/L-10 g/L. The concentration of potassium ferrate in the desorbing liquid can be, but not limited to, 1 g/L, 3 g/L, 5 g/L, 7 g/L, or 10 g/L. In some embodiments of the present disclosure, the adsorbent includes a manganese-based lithium ion sieve, and the desorbing liquid includes an acid solution and a hypochlorite. The dissolution loss of the manganese-based lithium ion sieve can also be reduced by adding a hypochlorite to the desorbing liquid. In some embodiments of the present disclosure, the concentration of the hypochlorite in the desorbing liquid is 1 g/L-10 g/L. The concentration of the hypochlorite in the desorbing liquid can be, but not limited to, 1 g/L, 3 g/L, 5 g/L, 7 g/L, or 10 g/L. In some embodiments of the present disclosure, the adsorbent includes a manganese-based lithium ion sieve, and the desorbing liquid includes an acid solution, a hypochlorite and potassium ferrate. In some embodiments of the present disclosure, after one round of adsorption and desorption of the adsorbent is completed in the lithium extraction apparatus, the dissolution loss of the adsorbent is less than 0.05%. During the lithium extraction process, potassium ferrate in the desorbing liquid may enter the lithium extract, the iron impurities produced by potassium ferrate can be removed by adjusting the pH of the lithium extract to precipitate iron ions into ferric hydroxide, so they will not affect the subsequent lithium extraction process.
The embodiments of the present disclosure are further described below in combination with examples.
A lithium extraction process using a lithium extraction apparatus having a structure as shown in
Example 2 differs from Example 1 in that the lithium extraction apparatus has a different structure. The structure of the lithium extraction apparatus used in Example 2 is shown in
Example 3 differs from Example 1 in that the lithium extraction apparatus has a different structure. The structure of the lithium extraction apparatus used in Example 3 is shown in
Example 4 differs from Example 1 in that the ingredients in the desorbing liquid are different. The concentration of each component in the desorbing liquid in Example 4 includes: 7 g/L of sulfuric acid, and 5 g/L of sodium hypochlorite.
Comparative Example 1 differs from Example 1 in that the lithium extraction apparatus has a different structure. The adsorption zone and desorption zone of the lithium extraction apparatus in Comparative Example 1 both have a single-layer structure. The structure of the lithium extraction apparatus used in Comparative Example 1 is shown in
To verify the effect of the lithium extraction apparatus and lithium extraction process of the present disclosure, effect examples are provided in the present disclosure. In the effect examples, brine with the following ingredients is used. The composition of the brine is shown in Table 1.
Lithium is extracted from the brine according to the following process.
The brine spraying device is opened, and a lithium containing adsorbent is obtained after the brine is adsorbed by the adsorbent. The lithium containing adsorbent is rinsed with water in the rinsing zone, and then fed to the desorption zone, where lithium ions in the lithium containing adsorbent is eluted off by the desorbing liquid, to obtain a lithium extract.
The contents of lithium and manganese in the lithium extraction solution are determined. The test results are shown in Table 2.
It can be seen from Table 2 that the transmission mesh belt in the adsorption zone and desorption zone of the lithium extraction apparatus in Example 1 both have a multi-layer structure, and the content of lithium in the obtained lithium extract is greater than that in the lithium extracts obtained in Example 2 and Example 3. The transmission mesh belt in the adsorption zone of the lithium extraction apparatus in Example 2 has a multi-layer structure, the transmission mesh belt in the desorption zone has a single-layer structure, and the content of lithium in the lithium extract is greater than that in the lithium extract in Comparative Example 1. The transmission mesh belt in the desorption zone of the lithium extraction apparatus in Example 3 has a multi-layer structure, the transmission mesh belt in the adsorption zone has a single-layer structure, and the content of lithium in the lithium extract is greater than that in the lithium extract in Comparative Example 1. It can be seen that the lithium extraction apparatus provided in the present disclosure can effectively improve the extraction rate of lithium in brine.
As can be seen from Example 4 and Example 1, an appropriate amount of potassium ferrate is added in the desorbing liquid to reduce the dissolution loss of the manganese adsorbent, thereby improving the cycle performance and service life of the adsorbent, reducing the number of replacements of the adsorbent, simplifying the process, and realizing highly automatic lithium extraction.
The foregoing embodiments only describe an implementation of the present disclosure, which are described specifically and in detail, and therefore shall not be construed as a limitation to the patent scope of the present disclosure. It is to be noted that, a person of ordinary skill in the art may further make variations and improvements without departing from the ideas of the present disclosure, and the variations and improvements shall fall within the protection scope of the present disclosure. Therefore, the patent protection scope of the present disclosure is subject to the protection scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202111682549.X | Dec 2021 | CN | national |
