A high power negative electrode focus method formed by low temperature oxidation

Abstract

The application discloses a high-power negative electrode coke method formed by low-temperature oxidation, and belongs to the technical field of needle coke preparation, and is characterized in that the high-power negative electrode coke method comprises the following steps: pretreatment of catalytic oil slurry, catalytic crosslinking reaction, coking reaction and mesophase growth reaction; the beneficial effects of the application are that the addition of a catalytic crosslinking agent and an acidic catalyst into extracted oil can effectively promote the preliminary crosslinking of the extracted oil, is conducive to the formation of part of irregular planar structures in the extracted oil, and meanwhile, the mesophase molecules generated by the catalytic crosslinking agent and the acidic catalyst at low temperature can further develop into small flake structures in the later coking process.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of needle coke preparation, and more particularly relates to a high-power negative electrode coke formed by low-temperature oxidation. BACKGROUND

[0002] As a new type of carbon material, needle coke has the characteristics of high capacity, good stability and adjustable structure, and is a high-quality raw material for producing high-performance negative electrode materials. The performance of needle coke determines the properties of the negative electrode material.

[0003] The capacity per unit volume is the most important indicator of needle coke for negative electrodes, and is of great significance. There are many production processes for negative electrodes, which can generally be divided into grinding, shaping, coating and granulation, carbonization, graphitization and other processes. Each process can be adjusted and improved according to the needs of the negative electrode. The rate performance can be improved by adding a portion of high-rate petroleum coke, but the addition of petroleum coke will inevitably reduce the overall density of the negative electrode, affecting the overall capacity performance of the battery.

[0004] The growth degree of the mesophase in the needle coke generally determines the capacity and rate properties of the entire needle coke. Adjusting the structure of the needle coke can take into account the kinetic performance on the basis of maintaining the capacity, and the coke has a moderate hardness, a high yield in the shaping stage, and can be used alone as a power battery coke. SUMMARY

[0005] To solve the above problems and overcome the shortcomings of the prior art, the application provides a high-power negative electrode coke formed by low-temperature oxidation, which can effectively solve the problems of capacity and rate properties of needle coke, and take into account the kinetic performance.

[0006] The specific technical scheme for solving the above technical problems is that the high-power negative electrode coke formed by low-temperature oxidation comprises:

[0007] (1) Pretreatment of catalytic oil slurry;

[0008] The catalytic oil slurry is fed into a vacuum device, and after cutting off the light components and heavy components by vacuum distillation, the extracted oil is obtained by entering an extraction device;

[0009] (2) Catalytic crosslinking reaction:

[0010] The obtained extracted oil is added to a catalytic crosslinking agent and an acidic catalyst, and low-temperature crosslinking is carried out in an air atmosphere, the crosslinking temperature is 100-300 DEG C, and the crosslinking time is 10-200 min;

[0011] (3) Coking reaction

[0012] The crosslinked extraction oil is added to a coking raw material tank after being filtered by sedimentation, the heating furnace is heated to 460-520 DEG C, the coking raw material oil is fed in, and the circulating oil is fed in, the circulating ratio (1:1-1:2), and the pressure is 0.5-1 MPa.

[0013] Further, the pre-treatment distillation range section condition of the catalytic oil slurry is <560 DEG C, after cutting out light components and heavy components by vacuum distillation, the extraction oil is obtained by entering an extraction device, and the aromatic content of the extraction oil is 50%-90%.

[0014] Further, the catalytic crosslinking agent is AlCl3, and the acidic catalyst is a sulfonic acid catalyst.

[0015] Further, the addition amount of the AlCl3 and the sulfonic acid catalyst is 0.01-1% of the mass of the extraction oil.

[0016] Further, the coking reaction further comprises an intermediate phase growth reaction.

[0017] The intermediate phase growth reaction: after 8 hours of coking reaction, the heating furnace temperature is gradually increased at 2 DEG C / h to 500 DEG C-540 DEG C, and the circulating ratio is reduced to 0.5:1-1:1 at 0.1 / h.

[0018] Further, the circulating oil is a coke tower distillate oil of the coking raw material oil at 0.1 MPa and 430 DEG C, and is light wax oil.

[0019] The beneficial effects of the present application are:

[0020] The needle coke produced by the production process has a 5C rate charging lithium removal capacity of 345.15 Ah / g, which is much higher than the previous 333.95 mAh / g.

[0021] (1) The addition of the catalytic crosslinking agent and the acidic catalyst to the extraction oil can effectively promote the preliminary crosslinking of the extraction oil, and is conducive to the formation of part of the irregular planar structure in the extraction oil, and the intermediate phase molecules generated by the catalytic crosslinking agent and the acidic catalyst at low temperature will further develop into small plate structures in the later coking process.

[0022] (2) The filtered catalytic crosslinking agent can be reused, thereby reducing the cost; the acidic catalyst is changed into a gas state in the crosslinking process and can be recycled and reused.

[0023] (3) The coking raw material oil is fed in at a relatively low temperature, which can effectively protect the heating furnace tube, prevent the furnace tube from coking, and further maintain the smoothness of the raw material oil entering the needle coke channel and the service life of the heating furnace.

[0024] (4) Gradual heating during the feeding process can ensure the uniform heating of coke in the coke tower. At the same time, the high temperature in the later stage is conducive to the further development of the meso phase and is more conducive to the increase of needle coke capacity. Attached image description:

[0025] Appendix Figure 1 This is a diagram showing the optical performance of the needle focal plane in Embodiment 3 of the present invention;

[0026] Appendix Figure 2 This is a diagram showing the optical performance of the needle focal plane in Embodiment 4 of the present invention;

[0027] Appendix Figure 3 This is a diagram showing the optical performance of the needle focal plane in Comparative Example 1 of the present invention;

[0028] Appendix Figure 4 This is a diagram showing the optical performance of the needle-shaped focal plane in Comparative Example 2 of the present invention;

[0029] Appendix Figure 5 This is a diagram showing the optical performance of the needle-shaped focal plane in Comparative Example 3 of the present invention;

[0030] Appendix Figure 6 This is a diagram showing the optical performance of the needle-shaped focal plane in Comparative Example 4 of the present invention;

[0031] Appendix Figure 7 This is a comparative example 5 of the optical performance diagram of the needle focal plane of the present invention;

[0032] Appendix Figure 8 This is a comparative example 5' of the optical performance of the needle focal plane of the present invention;

[0033] Appendix Figure 9 This is a diagram showing the optical performance of the needle-shaped focal plane in Comparative Example 6 of the present invention;

[0034] Appendix Figure 10 This is a diagram showing the optical performance of the needle-shaped focal plane in Comparative Example 7 of the present invention; Detailed implementation method:

[0035] Specific details in the description of this invention are merely to provide a thorough understanding of the embodiments thereof; however, those skilled in the art should understand that the implementation of this invention is not limited to these details. Furthermore, well-known structures and functions have not been described or shown in detail to avoid obscuring the key points of the embodiments of this invention. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0036] Specific embodiments of the present invention:

[0037] For better understanding of the present application, it is worth emphasizing that the effects of the examples have no substantial difference with various embodiments within the scope of the present application, including respective reagents and content ratio of reagents, which can all achieve the effects described in the present application and solve the above problems, and other combinations are not listed here.

[0038] The specific technical solution of the present application to solve the above technical problems is:

[0039] Example 1:

[0040] The high-power negative electrode coke method formed by low-temperature oxidation comprises:

[0041] (1) Pretreatment of catalytic oil slurry;

[0042] The catalytic oil slurry enters the vacuum device, and after cutting out the light component and the heavy component by vacuum distillation, it enters the extraction device to obtain extracted oil;

[0043] Further, the distillation section condition of the pretreatment of the catalytic oil slurry is <560℃, and after cutting out the light component and the heavy component by vacuum distillation, the extracted oil is obtained by entering the extraction device, and the aromatic content of the extracted oil is 50%-90%.

[0044] (2) Catalytic crosslinking reaction:

[0045] The obtained extracted oil is added with a catalytic crosslinking agent and an acidic catalyst, and low-temperature crosslinking is carried out in an air atmosphere, the crosslinking temperature is 300℃, and the crosslinking time is 200min;

[0046] Further, the catalytic crosslinking agent is AlCl3; and the acidic catalyst is a sulfonic acid catalyst.

[0047] Further, the addition amount of AlCl3 and the sulfonic acid catalyst is 1% of the mass of the extracted oil.

[0048] (3) Coking reaction

[0049] After the crosslinked extracted oil is settled and filtered, it is added into a coking raw material tank, the heating furnace is heated to 520℃, the coking raw material oil is fed in, and the circulating oil is also fed in, the circulation ratio is 1:2, and the pressure is 1MPa.

[0050] Further, the circulating oil is the coke tower distillate oil of the coking raw material oil at 0.1MPa and 430℃, which is light wax oil.

[0051] (4) Mesophase growth reaction:

[0052] The mesophase growth reaction: after 8 hours of coking reaction feeding, the heating furnace temperature is gradually increased at 2℃ / h to 540℃, and at the same time, the circulation ratio is reduced to 1:1 at 0.1 / h.

[0053] (5) stripping reaction:

[0054] After 24 hours of coking, the feeding is stopped, the stripping temperature is raised to 560℃ at a rate of 30℃ / h, and the stripping is performed for 8 hours, then the coking and decoking are started;

[0055] Example 2:

[0056] The high-power negative electrode coke formed by low-temperature oxidation comprises:

[0057] (1) pretreatment of catalytic oil slurry;

[0058] The catalytic oil slurry is fed into a vacuum device, and after light components and heavy components are cut out by vacuum distillation, extracted oil is obtained by entering an extraction device;

[0059] Further, the distillation range condition of the pretreatment of the catalytic oil slurry is <560℃, and after the light components and the heavy components are cut out by vacuum distillation, the extracted oil is obtained by entering the extraction device, and the aromatic content of the extracted oil is 50%-90%.

[0060] (2) catalytic crosslinking reaction:

[0061] The obtained extracted oil is added with a catalytic crosslinking agent and an acidic catalyst, and low-temperature crosslinking is performed in an air atmosphere, the crosslinking temperature is 100℃, and the crosslinking time is 10 min;

[0062] Further, the catalytic crosslinking agent is AlCl3, and the acidic catalyst is a sulfonic acid catalyst.

[0063] Further, the addition amount of the AlCl3 and the sulfonic acid catalyst is 0.01% of the mass of the extracted oil.

[0064] (3) coking reaction

[0065] After the crosslinked extracted oil is settled and filtered, it is added into a coking raw material tank, a heating furnace is heated to 460℃, coking raw material oil is fed in, and circulating oil is also fed in, the circulation ratio is 1:1, and the pressure is 0.5 MPa.

[0066] Further, the circulating oil is coke tower distillate oil of the coking raw material oil at 0.1 MPa and 430℃, which is light wax oil.

[0067] (4) mesophase growth reaction:

[0068] The mesophase growth reaction: after the coking reaction is fed in for 8 hours, the heating furnace temperature is gradually raised at a rate of 2℃ / h to 500℃, and at the same time, the circulation ratio is reduced to 0.5:1 at a rate of 0.1 / h.

[0069] (5) stripping reaction:

[0070] After 24 hours of coke formation, the feed is stopped, the stripping temperature is raised to 520℃ at a rate of 30℃ / h, and stripping is carried out for 8 hours, after which the stripping is stopped and the coke is cooled and removed;

[0071] Example 3:

[0072] The high-power negative electrode coke method formed by low-temperature oxidation comprises:

[0073] (1) Pretreatment of catalytic oil slurry;

[0074] The catalytic oil slurry is fed into a vacuum device, and after cutting out light components and heavy components by vacuum distillation, extracted oil is obtained by entering an extraction device;

[0075] Further, the distillation range conditions of the catalytic oil slurry pretreatment are <560℃, and after cutting out light components and heavy components by vacuum distillation, extracted oil is obtained by entering an extraction device, and the aromatic content of the extracted oil is up to 70%.

[0076] (2) Catalytic crosslinking reaction:

[0077] The obtained extracted oil is added with a catalytic crosslinking agent and an acidic catalyst, and low-temperature crosslinking is carried out in an air atmosphere, the crosslinking temperature is 200℃, and the crosslinking time is 100min;

[0078] Further, the catalytic crosslinking agent is AlCl3, and the acidic catalyst is a sulfonic acid catalyst.

[0079] Further, the addition amount of AlCl3 and the sulfonic acid catalyst is 0.05% of the mass of the extracted oil.

[0080] (3) Coking reaction

[0081] After the crosslinked extracted oil is settled and filtered, it is added to a coking raw material tank, the heating furnace is heated to 480℃, coking raw oil is fed in, and circulating oil is also fed in, the circulation ratio is 1:1.5, and the pressure is 0.75MPa.

[0082] Further, the circulating oil is coke tower distillate oil of coking raw oil at 0.1MPa and 430℃, which is light wax oil.

[0083] (4) Mesophase growth reaction:

[0084] The mesophase growth reaction: after 8 hours of coking reaction feed, the heating furnace temperature is gradually raised at a rate of 2℃ / h to 520℃, and at the same time, the circulation ratio is reduced to 0.75:1 at a rate of 0.1 / h.

[0085] (5) Stripping reaction:

[0086] After 24 hours of coke formation, the feed is stopped, the stripping temperature is raised to 520℃ at a rate of 30℃ / h, and stripping is carried out for 8 hours, after which the stripping is stopped and the coke is cooled and removed.

[0087] In order to more intuitively show the process advantages of the present application, the high-power negative electrode coke formed by low-temperature oxidation and the method of equivalent replacement of the same process are compared,

[0088] Comparative Example 1:

[0089] The preparation method is the same as that of the examples, except that no catalytic crosslinking agent is added in the catalytic crosslinking reaction in the preparation process of the comparative example;

[0090] Comparative Example 2:

[0091] The preparation method is the same as that of Example 3, except that no acidic catalyst is added in the catalytic crosslinking reaction in the preparation process of the comparative example;

[0092] Comparative Example 3:

[0093] The preparation method is the same as that of Example 3, except that no catalytic crosslinking agent and no acidic catalyst are added in the catalytic crosslinking reaction in the preparation process of the comparative example;

[0094] Comparative Example 4:

[0095] The preparation method is the same as that of Example 3, except that high-temperature crosslinking is used in the catalytic crosslinking reaction in the preparation process of the comparative example, with the condition being to control the reaction temperature to 300-400°C for crosslinking;

[0096] Comparative Example 5:

[0097] The preparation method is the same as that of Comparative Example 4, except that high-temperature constant-temperature coke formation is used in the intermediate phase growth reaction in the preparation process of the comparative example, with the condition being to control the reaction temperature to 480-510°C for constant-temperature coke formation;

[0098] Comparative Example 5':

[0099] The preparation method is the same as that of Example 3, except that high-temperature constant-temperature coke formation is used in the intermediate phase growth reaction in the preparation process of the comparative example, with the condition being to control the reaction temperature to 480-510°C for constant-temperature coke formation;

[0100] Table 1: Effect of different processes on the performance of needle coke

[0101]

[0102] According to the data analysis of Table 1:

[0103] (1) Compared with Examples 3 and Comparative Examples 1-3:

[0104] The delithiation capacities of Comparative Examples 1-3, 341.71 mAh / g, 342.25 mAh / g and 338.57 mAh / g, are much lower than that of the embodiment, 345.15 mAh / g, because in the catalytic cross-linking reaction process step, no catalytic cross-linking agent and / or acidic catalyst is added, which results in that the material cannot undergo cross-linking reaction during the catalytic cross-linking reaction. The acidic catalyst is used to accelerate the progress of the reaction. Since the catalytic cross-linking reaction time is relatively short, the acidic catalyst can to some extent promote the cross-linking degree within a certain time, thereby improving the final 5C rate charging delithiation capacity.

[0105] (2) Compared with Comparative Example 4, Example 3 has:

[0106] Although Comparative Example 4 uses a catalytic cross-linking agent and an acidic catalyst, the cross-linking reaction process using the catalytic cross-linking agent and the acidic catalyst adopts “high-temperature cross-linking”, which is to control the reaction temperature to 300-400°C for cross-linking. This will lead to over-cross-linking reaction. The specific principle is that, at a temperature of 300-400°C for cross-linking, the coking feedstock reacts too fast due to the high temperature, and the cross-linking reaction is excessive. When entering the coke tower, the feedstock with cross-linked structure rapidly forms coke without the process of intermediate phase development, thereby forming a small particle inlaid structure with low delithiation capacity.

[0107] After repeated experiments, it is found that, on the basis of Comparative Example 3, i.e., without using a catalytic cross-linking agent and an acidic catalyst, and then using high-temperature treatment, coking will occur in the furnace tube, and the reaction cannot proceed.

[0108] (3) Compared with Comparative Example 5, Comparative Example 4 has:

[0109] The delithiation capacities of Comparative Examples 4 and 5 are not much different, which is due to “high-temperature cross-linking”. When entering the coke tower, coke is rapidly formed without the process of intermediate phase development, thereby forming an inlaid structure coke. Once this structure is formed, the structure cannot grow and develop even after the intermediate phase growth reaction under the gradient temperature rising, and a needle-shaped coke structure beneficial to delithiation capacity is not formed.

[0110] (4) Compared with Comparative Example 5’, Example 3 has:

[0111] The difference lies in that, in the preparation process of the present comparative example, the intermediate phase growth reaction adopts high-temperature constant-temperature coking, and the delithiation capacity is reduced. This is because the gradient temperature rising is beneficial to the growth of the intermediate phase, and under this condition, a needle-shaped coke structure with large pieces and inlaid structure is produced, so the delithiation capacity is higher.

[0112] As another preferred embodiment of the present application, the present application also adopts an intermediate solidification reaction, and the technical effect achieved is that the circulating oil is stopped after feeding, which helps the further formation of the mesophase structure, and at the same time, makes up the skeleton defects caused by the overflow of small molecules of the needle coke, so as to further condense, and help the further increase of the true density of the needle coke, and at the same time, make it have a more uniform mesophase structure.

[0113] Specifically,

[0114] (1) Pretreatment of the FCC slurry;

[0115] The FCC slurry is fed into a vacuum device, and after the light components and heavy components are cut out by vacuum distillation, the extracted oil is obtained by entering an extraction device;

[0116] Further, the distillation section condition of the pretreatment of the FCC slurry is <560℃, and after the light components and heavy components are cut out by vacuum distillation, the extracted oil is obtained by entering an extraction device, and the aromatic content of the extracted oil is 50%-90%.

[0117] (2) Catalytic crosslinking reaction:

[0118] The obtained extracted oil is added with a catalytic crosslinking agent and an acidic catalyst, and low-temperature crosslinking is carried out in an air atmosphere, the crosslinking temperature is 100-300℃, and the crosslinking time is 10-200min;

[0119] Further, the catalytic crosslinking agent is AlCl3, and the acidic catalyst is a sulfonic acid catalyst.

[0120] Further, the addition amount of the AlCl3 and the sulfonic acid catalyst is 0.01%-1% of the mass of the extracted oil.

[0121] (3) Coking reaction

[0122] After the crosslinked extracted oil is settled and filtered, it is added into a coking raw material tank, the heating furnace is heated to 460-520℃, the coking raw oil is fed in, and at the same time, the circulating oil is fed in, the circulation ratio is 1:1-1:2, and the pressure is 0.5-1MPa.

[0123] Further, the circulating oil is the coking tower distillate oil of the coking raw oil at 0.1MPa and 430℃, which is light wax oil.

[0124] (4) Mesophase growth reaction:

[0125] The mesophase growth reaction is that the heating furnace temperature is gradually increased to 500-540℃ at 2℃ / h after 8 hours of coking reaction feeding, and at the same time, the circulation ratio is reduced to 0.5:1-1:1 at 0.1 / h.

[0126] (5) Intermediate solidification reaction;

[0127] After 24 hours of coke formation, the feeding is stopped, the temperature and the cycle oil feeding are maintained for 4 hours, after 4 hours the cycle oil is stopped, the stripping temperature is increased to 520-560℃, the stripping is performed for 16 hours, the stripping is stopped, the coke cooling and removal are started;

[0128] In order to more intuitively show the process advantages of the present application, the high-power negative electrode coke formed by the low-temperature oxidation method of the present application is combined with the intermediate solidification reaction, and the same process is used for equivalent replacement comparison,

[0129] Comparative Example 6:

[0130] The preparation method is the same as that of Example 4, except that no catalytic crosslinking agent and acidic catalyst are added during the preparation process of the present comparative example;

[0131] Comparative Example 7:

[0132] The preparation method is the same as that of Comparative Example 4, except that high-temperature crosslinking is used in the preparation process of the present comparative example, and the reaction temperature is controlled at 480-520℃ constant temperature;

[0133] Table 2: Comparison data of the influence of intermediate solidification reaction on the performance of needle coke

[0134]

[0135] According to the data analysis in Table 2, it can be seen that:

[0136] Comparative Example 4 and Example 3: The needle coke has a lithium extraction capacity of 348.59 mAh / g at 5C rate, which may be due to the effect of intermediate solidification reaction. The principle is that the intermediate solidification reaction is used: after stopping the feeding, the cycle oil is fed, which realizes the technical effect that after stopping the feeding, the cycle oil is fed, which helps the further formation of the intermediate phase structure, at the same time, it makes up for the skeleton defects of the needle coke due to the overflow of small molecules, thereby further condensing, which is beneficial to the further improvement of the true density of the needle coke, at the same time, it makes the intermediate phase structure more uniform, and finally some defect structures existing in the coking process are further developed, and on this basis, a large piece of needle coke structure with embedded structure is formed;

[0137] However, the lithium extraction capacity difference between Comparative Example 3 and Comparative Example 6 is not large, and the lithium extraction capacity difference between Comparative Example 4 and Comparative Example 7 is also not large, so whether the intermediate solidification reaction is used or not, the lithium extraction capacity difference of the above comparative examples is not large,

[0138] This may be due to the fact that no catalytic crosslinking agent and acidic catalyst are added in Comparative Example 3 and Comparative Example 6, and high-temperature crosslinking of Comparative Example 4 and Comparative Example 7, which leads to the failure of crosslinking reaction, and the catalytic crosslinking agent and acidic catalyst and low-temperature crosslinking reaction can effectively promote the preliminary crosslinking of the extracted oil, which is beneficial to the formation of part of the irregular planar structure in the extracted oil, and the intermediate phase molecules generated by the catalytic crosslinking agent and acidic catalyst at low temperature will further develop and grow into a sheet shape in the later coking process, with a certain mosaic structure, and the crosslinking reaction cannot be carried out, resulting in the generation of large mosaic structure, even if the intermediate solidification reaction is used later, the structure cannot be regenerated and restored, finally leading to the failure to form the needle-shaped coke structure with large mosaic structure of the present application,

[0139] The needle-shaped coke structure with large mosaic structure improves the capacity of the needle-shaped coke and improves the kinetic performance, and it is found that the compaction density of the negative electrode sheet prepared by the process is improved compared with before.

[0140] It is worth emphasizing that: according to the consensus of the negative electrode industry, the negative electrode quality is improved by 3 milliampere hours in the negative electrode field, and the negative electrode is improved by 15 milliampere hours compared with the previous conventional method, which greatly improves the rate performance of the negative electrode.

[0141] In summary:

[0142] The needle-shaped coke produced by the production process has a 5C rate charging lithium extraction capacity of 348.59 mAh / g, which is much higher than the previous 333.95 mAh / g.

[0143] The present application (1) adding a catalytic crosslinking agent and an acidic catalyst to the extracted oil can effectively promote the preliminary crosslinking of the extracted oil, which is beneficial to the formation of part of the irregular planar structure in the extracted oil, and the intermediate phase molecules generated by the catalytic crosslinking agent and acidic catalyst at low temperature will further develop into small sheet structure in the later coking process;

[0144] (2) The filtered catalytic crosslinking agent can be reused, reducing the cost; the acidic catalyst is changed into a gaseous state during the crosslinking process and can be recycled and reused.

[0145] (3) The catalytic crosslinking reaction in the coking raw material oil at a lower temperature can effectively protect the furnace tube of the heating furnace and prevent the furnace tube from coking, thereby further maintaining the flow of the raw material oil into the needle-shaped coke channel and the service life of the heating furnace.

[0146] (4) The gradient temperature rise during the feeding process can ensure the uniformity of the heating of the coke in the coke tower, and the high temperature in the later stage is beneficial to the development of the intermediate phase of the needle coke, which is more beneficial to the improvement of the capacity of the needle-shaped coke;

[0147] (5) The process can further develop into small piece structure based on the late stage coking process of the intermediate phase molecules generated by the catalytic crosslinking agent and acidic catalyst at low temperature, combined with the growth reaction of the intermediate phase and the intermediate curing reaction to form the needle coke structure with large piece and mosaic structure, which can improve the capacity and kinetic performance of the needle coke, and the compaction density of the negative electrode sheet prepared by the process is also improved.

Claims

1. A high-energy negative electrode coke process formed by low-temperature oxidation, characterized by The high-power negative electrode coking method comprises: (1) pretreatment of catalytic oil slurry; The catalytic oil slurry is introduced into a vacuum device, light components and heavy components are cut off by vacuum distillation, and then the extracted oil is obtained by extraction; (2) catalytic crosslinking reaction: The obtained extracted oil is added with a catalytic crosslinking agent and an acidic catalyst, and low-temperature crosslinking is carried out in an air atmosphere, the crosslinking temperature is 100-300℃, and the crosslinking time is 10-200 min; the catalytic crosslinking agent is AlCl3; the acidic catalyst is a sulfonic acid catalyst, and the addition amount of the AlCl3 and the sulfonic acid catalyst is 0.01-1% of the mass of the extracted oil; (3) coking reaction After the crosslinked extracted oil is settled and filtered, it is added into a coking raw material tank, a heating furnace is heated to 460-520℃, coking raw oil is fed, circulating oil is fed at the same time, and the pressure is 0.5-1 MPa; (4) mesophase growth reaction; The mesophase growth reaction: after the coking reaction is fed for 8 hours, the heating furnace temperature is gradually increased, and is increased to 500-540℃ at a rate of 2℃ / h, and at the same time, the circulation ratio is changed from 1:2 to 1:1 or from 1:1 to 0.5:1 or from 1:1.5 to 0.75:

1.

2. The high-energy negative pole focus method formed by low-temperature oxidation according to claim 1, characterized in that The distillation range section condition of the pretreatment of the catalytic oil slurry is <560℃, light components and heavy components are cut off by vacuum distillation after the extracted oil is obtained by extraction, and the aromatic content of the extracted oil is 50%-90%.

3. The high-energy negative pole focus method formed by low-temperature oxidation according to claim 1 or 2, characterized in that The circulating oil is coking raw oil at 0.1 MPa and 430℃, which is coking tower distillate oil, and is light wax oil.

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