A chemical immersion discharge method for waste sodium ion batteries

Abstract

The invention discloses a chemical immersion discharge method for waste sodium ion batteries, and belongs to the technical field of battery recycling. The specific preparation method comprises: adding a metal salt and an additive into a solvent to obtain a discharge solution, and then placing the waste sodium ion battery in the discharge solution and standing for discharge treatment; the metal salt is at least one of sodium chloride, ferrous sulfate and ferric sulfate; the additive is cinnamamide salt; and the solvent is water. The invention has a good discharge effect and discharge efficiency for waste sodium ion batteries, which is not only helpful for relatively thorough discharge, but also can significantly shorten the discharge time and achieve efficient discharge.

Description

Technical Field

[0001] The invention belongs to the technical field of battery recycling, and in particular relates to a chemical immersion discharge method for waste sodium ion batteries. Background Art

[0002] Waste sodium ion batteries need to be discharged before processing to eliminate residual voltage and avoid safety problems. At present, there are two major types of discharge methods for waste sodium ion batteries, physical discharge method and chemical discharge method. Patent CN106816663A adopts a physical discharge method, mixing waste batteries with conductive powder and then discharging them statically. This method can make the conductive powder fully contact with the positive and negative electrodes of the waste batteries, and effectively discharge the waste batteries, but the high cost is not suitable for large-scale use. At the same time, it is easy to release a large amount of heat energy due to battery short circuit during the discharge process, causing the temperature to rise sharply and causing safety accidents. Patent CN106558739A adopts a chemical discharge method, placing the lithium ion battery in a sodium chloride solution with a mass concentration of 5-10% for immersion for 48h discharge. This method is simple to operate, but the discharge time required is long and the discharge is incomplete. At the same time, the high concentration of chloride ions in the chloride salt system is easy to corrode the battery and equipment, and hydrogen and chlorine will be generated during the immersion discharge process to produce danger. Therefore, the existing discharge method of waste sodium ion batteries needs to be further improved. Summary of the invention

[0003] The object of the present invention is to provide a chemical immersion discharge method for waste sodium ion batteries, so as to solve the problems of high cost, long discharge time and unsafety of the discharge method for waste sodium ion batteries.

[0004] In order to solve the above technical problems, the present invention specifically provides the following technical solutions: The invention discloses a discharge solution for chemical immersion discharge of waste sodium ion batteries, comprising a metal salt, an additive and a solvent; the additive is cinnamamide salt and ferulic acid 4-O-sulfate disodium salt, and the cinnamamide salt is prepared by reacting 2-phenylethylamine, cinnamoyl chloride and citric acid. The use of cinnamamide salt and ferulic acid 4-O-sulfate disodium salt can provide a chemically mild environment for the discharge solution, and can promote the progress of the anode process and the cathode process, thereby achieving a better discharge effect and discharge efficiency.

[0005] Preferably, the metal salt includes at least one of sodium chloride, ferrous sulfate and ferric sulfate.

[0006] Preferably, the solvent is water.

[0007] The invention discloses a chemical immersion discharge method for waste sodium ion batteries, comprising: The metal salt and the additive are added into the solvent to obtain the discharge solution, and then the waste sodium ion battery is placed in the discharge solution and allowed to stand for discharge treatment.

[0008] Preferably, the metal salt includes at least one of sodium chloride, ferrous sulfate and ferric sulfate, and the amount of the metal salt added to the solvent is 0.5-1.5 mol / L.

[0009] Preferably, the additives are cinnamamide salt and ferulic acid 4-O-sulfate disodium salt, and the amount of the additives added to the solvent is 0.3-2 g / L.

[0010] Preferably, the solvent is water.

[0011] Preferably, the initial residual voltage value of the waste sodium ion battery is 3.6-3.65V.

[0012] Preferably, the standing temperature for the discharge treatment is 25-35°C.

[0013] Preferably, the standing time for the discharge treatment is 16-24 hours.

[0014] The present invention also discloses a method for preparing cinnamamide salt, which specifically comprises: First, 2-phenylethylamine is mixed with ethyl acetate, and then cinnamoyl chloride solution is added dropwise at 0-10°C for 2-3.5 hours. After the reaction, sodium hydroxide solution is added dropwise, and the organic phase is separated, dried, filtered, and rotary evaporated, and then recrystallized from isopropanol to obtain a cinnamamide intermediate. Methanol and citric acid are added to the intermediate product, and the reaction is carried out at 25°C for 2 hours. After the reaction is completed, rotary evaporated and dried to obtain cinnamamide salt.

[0015] Preferably, the usage ratio of 2-phenylethylamine to ethyl acetate is 1 g:8-12 ml.

[0016] Preferably, the cinnamoyl chloride solution consists of cinnamoyl chloride and ethyl acetate, and the usage ratio of cinnamoyl chloride to ethyl acetate is 1 g: 1.5-2.2 ml.

[0017] Preferably, the mass ratio of cinnamoyl chloride to 2-phenylethylamine is 1:0.4-0.9. Preferably, the sodium hydroxide solution consists of sodium hydroxide and water, and the dosage ratio of sodium hydroxide to water is 1g:3.5-5ml.

[0018] Preferably, the mass ratio of the amount of sodium hydroxide solution used to the amount of cinnamoyl chloride used is 1:0.5-1.2.

[0019] Preferably, the usage ratio of citric acid to methanol is 1 g: 8-15 ml.

[0020] Preferably, the mass ratio of the amount of citric acid used to the amount of the intermediate product used is 1:0.8-1.4.

[0021] More preferably, in the chemical immersion discharge method for waste sodium ion batteries, L-glutamine malate can be added on the basis of using cinnamamide salt and ferulic acid 4-O-sulfate disodium salt. The coordinated use of L-glutamine malate and cinnamamide salt makes the entire discharge solution system more gentle and stable, achieves stable discharge, and further improves the discharge effect and discharge efficiency of waste sodium ion batteries.

[0022] Preferably, the amount of L-glutamine malate added to the solvent is 0.3-0.75 g / L.

[0023] Compared with the prior art, the present invention has the following beneficial effects: The present invention proposes a chemical immersion discharge method for waste sodium ion batteries, wherein a metal salt and an additive are added to a solvent to obtain a discharge solution, and then the waste sodium ion batteries are placed in the discharge solution and allowed to stand for discharge treatment; the metal salt is at least one of sodium chloride, ferrous sulfate and ferric sulfate; the additive is cinnamamide salt; and the solvent is water. The present invention has a good discharge effect and discharge efficiency for waste sodium ion batteries, which is not only helpful for relatively thorough discharge, but also can significantly shorten the discharge time and achieve efficient discharge. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0025] Figure 1 This is the infrared characterization image of the cinnamamide intermediate; Figure 2 This is the graph of the voltage changing with time during the discharge process. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The following first describes the concepts involved in the present application in conjunction with the accompanying drawings. It should be noted that the following description of each concept is only to make the content of the present application easier to understand, and does not limit the scope of protection of the present application; at the same time, the embodiments and features in the embodiments of the present application can be combined with each other in the absence of conflict. The present application will be described in detail with reference to the accompanying drawings and in conjunction with the embodiments.

[0028] Embodiment 1: Chemical immersion discharge method for waste sodium ion batteries: sodium chloride is added to water to obtain a discharge solution, and then the waste sodium ion battery is placed in the discharge solution and left to stand at 26°C for 20 hours for discharge treatment. The amount of sodium chloride added to the water is 1 mol / L, and the initial voltage residual value of the waste sodium ion battery is 3.6V.

[0029] Embodiment 2: Chemical immersion discharge method for waste sodium ion batteries: Add ferrous sulfate to water to obtain a discharge solution, then place the waste sodium ion battery in the discharge solution and let it stand at 26°C for 20 hours for discharge treatment. The amount of ferrous sulfate added to the water is 1 mol / L, and the initial voltage residual value of the waste sodium ion battery is 3.6V.

[0030] Embodiment 3: Chemical immersion discharge method for waste sodium ion batteries: Add ferrous sulfate and ferric sulfate to water to obtain a discharge solution, then place the waste sodium ion battery in the discharge solution and let it stand at 26°C for 20 hours for discharge treatment. The amount of ferrous sulfate added to the water is 1 mol / L, the amount of ferric sulfate added to the water is 1 mol / L, and the initial voltage residual value of the waste sodium ion battery is 3.6V.

[0031] Embodiment 4: Preparation of cinnamamide salt: 2-phenylethylamine was mixed with ethyl acetate, cinnamoyl chloride solution was added dropwise at 4°C, and the reaction was continued for 2.5 hours. After the reaction was completed, sodium hydroxide solution was added dropwise, and the organic phase was separated, dried, filtered, and rotary evaporated, and then recrystallized from isopropanol to obtain the cinnamamide intermediate. Methanol and citric acid were added to the intermediate product, and the reaction was carried out at 25°C for 2 hours. After the reaction was completed, the cinnamamide salt was obtained by rotary evaporation and drying. The dosage ratio of 2-phenylethylamine to ethyl acetate is 1g:10ml, the cinnamoyl chloride solution consists of cinnamoyl chloride and ethyl acetate, the dosage ratio of cinnamoyl chloride to ethyl acetate is 1g:1.81ml, and the mass ratio of cinnamoyl chloride to 2-phenylethylamine is 1:0.61. The sodium hydroxide solution consists of sodium hydroxide and water, the dosage ratio of sodium hydroxide to water is 1g:4ml, and the mass ratio of sodium hydroxide solution to cinnamoyl chloride is 1:0.83. The dosage ratio of citric acid to methanol is 1g:12ml, and the mass ratio of citric acid to the intermediate product is 1:1.

[0032] Chemical immersion discharge method for waste sodium ion batteries: sodium chloride, cinnamamide salt and ferulic acid 4-O-sulfate disodium salt are added to water to obtain a discharge solution, and then the waste sodium ion battery is placed in the discharge solution and left to stand at 26°C for 20 hours for discharge treatment. The amount of sodium chloride added to the water is 1 mol / L, the amount of cinnamamide salt added to the water is 0.8 g / L, the amount of ferulic acid 4-O-sulfate disodium salt added to the water is 0.35 g / L, and the initial voltage residual value of the waste sodium ion battery is 3.6V.

[0033] Embodiment 5: The preparation of cinnamamide salt is the same as in Example 4.

[0034] Chemical immersion discharge method for waste sodium ion batteries: The chemical immersion discharge method for waste sodium ion batteries in this embodiment is compared with that in Example 4, except that the amount of cinnamamide salt added to water is 1 g / L, and other conditions and parameters are the same as in Example 4.

[0035] Embodiment 6: The preparation of cinnamamide salt is the same as in Example 4.

[0036] Chemical immersion discharge method for waste sodium ion batteries: The chemical immersion discharge method for waste sodium ion batteries in this embodiment is compared with that in Example 4, except that the amount of ferulic acid 4-O-sulfate disodium salt added to water is 0.45 g / L, and other conditions and parameters are the same as in Example 4.

[0037] Embodiment 7: The preparation of cinnamamide salt is the same as in Example 4.

[0038] Chemical immersion discharge method for waste sodium ion batteries: sodium chloride, cinnamamide salt, ferulic acid 4-O-sulfate disodium salt and L-glutamine malate are added to water to obtain a discharge solution, and then the waste sodium ion battery is placed in the discharge solution and left to stand at 26°C for 20 hours for discharge treatment. The amount of sodium chloride added to the water is 1 mol / L, the amount of cinnamamide salt added to the water is 0.8 g / L, the amount of ferulic acid 4-O-sulfate disodium salt added to the water is 0.35 g / L, the amount of L-glutamine malate added to the water is 0.4 g / L, and the initial voltage residual value of the waste sodium ion battery is 3.6V.

[0039] Embodiment 8: The preparation of cinnamamide salt is the same as in Example 4.

[0040] Chemical immersion discharge method for waste sodium ion batteries: The chemical immersion discharge method for waste sodium ion batteries in this embodiment is compared with that in Example 7, except that the amount of L-glutamine malate added to water is 0.6 g / L, and other conditions and parameters are the same as in Example 7.

[0041] Comparative Example 1: Chemical immersion discharge method for waste sodium-ion batteries: Place the waste sodium-ion batteries in water and let them stand for 20 hours for discharge treatment.

[0042] Comparative Example 2: The preparation of cinnamamide salt is the same as in Example 4.

[0043] Chemical immersion discharge method for waste sodium ion batteries: The chemical immersion discharge method for waste sodium ion batteries in this embodiment is different from that in Example 4 in that cinnamamide salt is not used, and other conditions and parameters are the same as in Example 4.

[0044] Comparative Example 3: Chemical immersion discharge method for waste sodium ion batteries: The chemical immersion discharge method for waste sodium ion batteries in this embodiment is compared with that in Example 4, except that ferulic acid 4-O-disodium sulfate is not used, and other conditions and parameters are the same as in Example 4.

[0045] Experimental Example 1: The cinnamamide intermediate product was characterized by infrared spectroscopy analysis of the cinnamamide intermediate product in Example 4, with a scanning range of 500-4000 cm-1. Figure 1 As shown, 3375cm -1 is the characteristic absorption peak of NH, 2800-3000cm -1 It is the characteristic absorption peak of -CH2, 1650cm -1 It is the characteristic absorption peak of C=O, 1609cm -1 It is the characteristic absorption peak of C=C, 650-750cm-1 It is the characteristic absorption peak of benzene ring CH.

[0046] Experimental Example 2: The chemical immersion discharge process of the waste sodium ion batteries of Comparative Example 1 and Examples 1-3 was monitored, and the voltage was recorded once every hour. The results are as follows: Figure 2 As shown, Comparative Example 1 of the present invention shows that the voltage of the waste sodium ion battery in water drops very slowly, which may be due to the large resistance of water and poor conductivity, which makes it impossible for the battery to discharge quickly; Example 1 shows that the voltage of the waste sodium ion battery has a downward trend in the first 5 hours, and then the voltage drop rate decreases; Example 2 shows that the voltage of the waste sodium ion battery can drop quickly to 1.39V in the first 12 hours. Example 3 shows that the voltage of the waste sodium ion battery can drop quickly to 0.88V in the first 8 hours, and the voltage drop rate is fast; Example 3 is compared with Examples 1-2 and Comparative Example 1, indicating that the joint use of ferrous sulfate and ferric sulfate can improve the discharge effect of the waste sodium ion battery.

[0047] Experimental Example 3: The voltage of the waste sodium ion batteries treated by the chemical immersion discharge method of the waste sodium ion batteries of Examples 1-7 and Comparative Examples 1-3 was measured.

[0048] Table 1 Voltage measurement results

[0049] The results are shown in Table 1. Compared with Example 1, Example 2 of the present invention shows that compared with sodium chloride, the discharge solution prepared by ferrous sulfate has a lower voltage after treating the waste sodium ion battery, that is, the discharge effect is better; Compared with Example 2, Example 3 shows that the discharge solution prepared by ferrous sulfate and ferrous sulfate has a better discharge effect on waste sodium ion batteries than the discharge solution prepared by adding only ferrous sulfate; Compared with Example 1, Example 4 shows that the use of cinnamamide salt and ferulic acid 4-O-disodium sulfate can improve the discharge effect of the prepared discharge solution on waste sodium ion batteries; Compared with Example 4, Example 5 shows that the increase in the use amount of cinnamamide salt within a certain range can improve the discharge effect of the prepared discharge solution on waste sodium ion batteries; Compared with Example 4, Example 6 shows that the increase in the use amount of ferulic acid 4-O-disodium sulfate within a certain range can also improve the discharge effect of the prepared discharge solution on waste sodium ion batteries. To improve the discharge effect of the prepared discharge solution on the waste sodium ion batteries; Example 7 is compared with Example 6, indicating that on the basis of using cinnamamide salt and ferulic acid 4-O-disodium sulfate, using L-glutamine malate can further improve the discharge effect of the prepared discharge solution on the waste sodium ion batteries; Example 7 is compared with Example 6, indicating that the increase in the usage of L-glutamine malate within a certain range can improve the discharge effect of the prepared discharge solution on the waste sodium ion batteries; Comparative Example 1 is compared with Example 1, indicating that compared with water, the discharge solution prepared using sodium chloride has a better discharge effect on the waste sodium ion batteries; Comparative Examples 1 and 2 are compared with Example 4, indicating that cinnamamide salt and ferulic acid 4-O-disodium sulfate need to be used together, and the discharge solution prepared by using any one of them alone has no obvious effect on improving the discharge effect of the waste sodium ion batteries.

[0050] Experimental Example 4: Determination of discharge efficiency: The chemical immersion discharge process of the waste sodium ion batteries of Comparative Example 1 and Examples 1-3 was monitored, the voltage was recorded once every hour, and the time required for the voltage value to drop below 2V was measured.

[0051] Table 1 The time required for the voltage value to drop to 2V

[0052] The results are shown in Table 2. Compared with Example 1, Example 2 of the present invention shows that compared with sodium chloride, the time required for the discharge solution prepared by ferrous sulfate to reduce the voltage value of the waste sodium ion battery to below 2V is less than that of Example 1, that is, the discharge efficiency is better; Compared with Example 2, Example 3 shows that the discharge solution prepared by ferrous sulfate and ferrous sulfate has better discharge efficiency than the discharge solution prepared by adding only ferrous sulfate; Compared with Example 1, Example 4 shows that the use of cinnamamide salt and ferulic acid 4-O-disodium sulfate can improve the discharge efficiency of the prepared discharge solution; Compared with Example 4, Example 5 shows that the increase in the use amount of cinnamamide salt within a certain range can improve the discharge efficiency of the prepared discharge solution; Compared with Example 4, Example 6 shows that the use of ferulic acid 4-O-disodium sulfate can improve the discharge efficiency of the prepared discharge solution. Increasing the usage within a certain range can also improve the discharge efficiency of the prepared discharge solution; compared with Example 6, Example 7 shows that on the basis of using cinnamamide salt and ferulic acid 4-O-disodium sulfate, the use of L-glutamine malate can further improve the discharge efficiency of the prepared discharge solution; compared with Example 6, Example 7 shows that increasing the usage of L-glutamine malate within a certain range can improve the discharge efficiency of the prepared discharge solution; compared with Example 1, Comparative Example 1 shows that the discharge efficiency of the discharge solution prepared using sodium chloride is better than that of water; compared with Example 4, Comparative Examples 1 and 2 show that cinnamamide salt and ferulic acid 4-O-disodium sulfate need to be used together, and the discharge solution prepared by using any one of them alone has no obvious effect on improving the discharge efficiency.

[0053] The embodiments and / or implementation methods described above are only used to illustrate the preferred embodiments and / or implementation methods for realizing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any form. Any technical personnel in this field may make slight changes or modifications to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as technologies or embodiments that are essentially the same as the present invention.

[0054] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and its core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concept and technical solution of the invention to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A discharge solution for chemical immersion discharge of waste sodium ion batteries, comprising a metal salt, an additive and a solvent; the additive is cinnamamide salt and ferulic acid 4-O-sulfate disodium salt, and the cinnamamide salt is prepared by reacting 2-phenylethylamine, cinnamoyl chloride and citric acid.

2. A discharge solution for chemical immersion discharge of waste sodium ion batteries according to claim 1, characterized in that: The metal salt includes at least one of sodium chloride, ferrous sulfate and ferric sulfate.

3. A discharge solution for chemical immersion discharge of waste sodium ion batteries according to claim 1, characterized in that: The solvent is water.

4. A method for chemical immersion discharge of waste sodium ion batteries, comprising: The metal salt and the additive are added into the solvent to obtain the discharge solution, and then the waste sodium ion battery is placed in the discharge solution and allowed to stand for discharge treatment.

5. A method for chemically immersing and discharging waste sodium ion batteries according to claim 4, characterized in that: The metal salt includes at least one of sodium chloride, ferrous sulfate and ferric sulfate, and the amount of the metal salt added to the solvent is 0.5-1.5 mol / L.

6. A method for chemically immersing and discharging waste sodium ion batteries according to claim 4, characterized in that: The additives are cinnamamide salt and ferulic acid 4-O-sulfate disodium salt, and the amount of the additives added to the solvent is 0.3-2 g / L.

7. A method for chemically immersing and discharging waste sodium ion batteries according to claim 4, characterized in that: The solvent is water.

8. A method for chemical immersion discharge of waste sodium ion batteries according to claim 4, characterized in that: The initial residual voltage value of the waste sodium ion battery is 3.6-3.65V.

9. A method for chemical immersion discharge of waste sodium ion batteries according to claim 4, characterized in that: The static temperature for the static discharge treatment is 25-35°C.

10. A method for chemical immersion discharge of waste sodium ion batteries according to claim 4, characterized in that: The standing time for the discharge treatment is 16-24 hours.

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