Petroleum-based coated asphalt as well as preparation method and application thereof

Abstract

The invention provides petroleum-based coated asphalt and a preparation method and application thereof, and belongs to the technical field of coated asphalts.The preparation method comprises the steps that raw material ethylene tar and an extraction agent are evenly mixed at a constant temperature and then extracted, and extract liquor is taken to obtain aromatic hydrocarbon-rich oil; the method comprises the following steps: carrying out reduced pressure distillation on aromatic hydrocarbon-rich oil, extracting a solvent and light components in the aromatic hydrocarbon-rich oil to obtain ethylene tar asphalt, and feeding the ethylene tar asphalt into a reaction kettle to carry out oxidation reaction to obtain coated asphalt. The method is simple in process flow, continuous in operation and high in controllability, and the prepared coated asphalt is high in softening point and coking value, low in quinoline insoluble content and ash content and excellent in performance by optimizing the process.

Description

Technical Field

[0001] The present invention relates to the technical field of coated asphalt, and in particular to a petroleum-based coated asphalt and a preparation method and application thereof. Background Art

[0002] Ethylene tar is a byproduct of hydrocarbon cracking to produce ethylene. Its primary components are aromatic compounds, characterized by short side chains, a high carbon-to-hydrogen ratio, low ash content, and low heavy metal content. my country produces a large amount of ethylene tar, but currently, most of it is used as fuel for boilers and cracking furnaces, with a smaller portion used as needle coke and carbon black. This wastes a valuable resource, necessitating further processing and utilization.

[0003] Currently, the mainstream raw material for producing coated asphalt on the market is mostly coal tar, which is environmentally unfriendly. Coal tar has high ash content and high levels of quinoline insolubles, which seriously affect the performance of the coated asphalt. However, there are very few studies and reports on petroleum-based coated asphalt.

[0004] Coated asphalt has a wide range of applications. In addition to being used as anode materials for lithium batteries, it can also be used as a raw material for the production of high-value-added asphalt-based carbon materials. Mesophase carbon microbeads, activated carbon, and carbon fibers can be produced using coated asphalt as a raw material. High-performance products can be used in military, medical, new energy, and aerospace industries. Currently, the negative electrode material of commercial lithium batteries is mainly graphite, but graphite has poor compatibility with electrolytes and is prone to irreversible decomposition in organic solvents, which causes the graphite layer to expand and contract, or even peel off, thereby reducing cycle efficiency and negatively affecting electrode performance. Coated asphalt, as a surface modification agent for graphite materials, obtains an amorphous carbon coating after carbonization, which modifies defects such as pores, grooves, and cracks in the graphite, thereby improving the electrochemical reversible capacity and cycle performance of the material.

[0005] In the production of graphite negative electrode materials, the coated asphalt currently used still has defects such as low asphalt softening point, low coking value, high quinoline insoluble matter content, high ash content and low yield. Summary of the Invention

[0006] The present invention uses ethylene tar as raw material, and prepares a type of petroleum-based coated asphalt through extraction, vacuum distillation and oxidation to solve the problems of high ash content and high quinoline insoluble matter content in coal tar, and produces a coated asphalt product with high softening point, high coking value and low quinoline insoluble matter content, thereby further improving the electrochemical performance of the negative electrode material.

[0007] One of the purposes of the present invention is to provide a method for preparing petroleum-based coated asphalt.

[0008] The second purpose of the present invention is to provide a petroleum-based coated asphalt obtained by the preparation method.

[0009] The third object of the present invention is to provide an application of the petroleum-based coated asphalt in the preparation of lithium battery negative electrode materials.

[0010] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are adopted:

[0011] In a first aspect, the present invention provides a method for preparing petroleum-based coated asphalt, comprising the following steps:

[0012] S1, mixing the raw material ethylene tar with an extractant to extract and obtain an upper aromatic oil-rich extract;

[0013] S2. subjecting the aromatics-rich oil extract to vacuum distillation to remove the solvent and light components therein to obtain ethylene tar pitch;

[0014] S3. Oxidizing the ethylene tar pitch to obtain petroleum-based coated asphalt.

[0015] The following is a detailed description of each step:

[0016] S1:

[0017] The extractant may be any extractant known in the art that can be used to extract aromatic hydrocarbons, preferably N-methyl-2-pyrrolidone or the like.

[0018] In some embodiments, the mass ratio of ethylene tar to extractant is 1:(0.8-1.5), for example 1:1, 1:1.2, 1:1.4, but not limited thereto. If the content of the extractant is too low, the extraction effect is poor, and if the content is too high, it will affect the effect of the vacuum distillation process and reduce the efficiency.

[0019] In some embodiments, the extraction conditions are as follows:

[0020] The extraction temperature is 50-65°C, and / or

[0021] The stirring speed during extraction is 100-300 r / min, and / or

[0022] The stirring time is 30 to 60 minutes. After stirring, let it stand at a constant temperature (e.g., 24 hours).

[0023] By extracting under these conditions, the aromatic components in the ethylene tar are enriched. The high aromatic content is conducive to the generation of polycyclic aromatic hydrocarbons during the oxidation process, thereby significantly increasing the softening point of the coated asphalt.

[0024] S2:

[0025] The aromatics-rich oil is subjected to vacuum distillation to extract the solvent and light components in the aromatics-rich oil to obtain ethylene tar pitch.

[0026] In some embodiments, the conditions of the reduced pressure distillation are as follows:

[0027] The distillation temperature is 220-280°C, and / or

[0028] Heating rate 4-6℃ / min, and / or

[0029] The stirring speed during distillation is 100-600 r / min, and / or

[0030] The vacuum degree is 2~10Pa.

[0031] By distilling under these conditions, the solvent and light components are removed. If vacuum distillation is not performed, there will be more light components in the ethylene tar pitch, which will lead to severe coking during the oxidation process and an increase in quinoline insolubles, affecting the properties of the product.

[0032] S3:

[0033] The ethylene tar pitch is then fed into a reactor for oxidation reaction to obtain coated asphalt.

[0034] In some embodiments, the oxidation reaction is carried out in the presence of air under the following conditions:

[0035] The reaction temperature is 280-380°C, and / or

[0036] Heating rate 4-6℃ / min, and / or

[0037] The reaction time is 1 to 10 hours, and / or

[0038] The stirring speed during the reaction is 100-600 r / min, and / or

[0039] Air flow rate is 1~10m 3 / h.

[0040] By carrying out oxidation under these conditions, the softening point and coking value of ethylene tar pitch are greatly improved.

[0041] The method of the present invention uses low-priced and readily available raw materials, has a simple process flow, is a continuous operation, and has high controllability. The prepared coated asphalt has a high softening point and coking value, low quinoline insoluble matter and ash content, and excellent performance.

[0042] In a second aspect, the present invention provides a petroleum-based coated asphalt prepared by the above-mentioned preparation method;

[0043] The petroleum-based coated asphalt has the following characteristics:

[0044] The softening point is not less than 270°C; the quinoline insoluble matter is less than 0.1%; the coking value is not less than 65%; and the ash content is less than 0.2%.

[0045] In a third aspect, the present invention provides an application of petroleum-based coated asphalt in the preparation of lithium battery negative electrode materials. Preferably, the lithium battery negative electrode material is a graphite material (natural graphite, artificial graphite), a silicon-based material, etc.

[0046] Lithium battery negative electrode materials can be further used in power batteries, energy storage batteries, new energy vehicles and other fields.

[0047] Beneficial effects

[0048] (1) The petroleum-based coated asphalt prepared by the present invention through the improvement of process steps and parameters has the characteristics of low quinoline insoluble matter content and low ash content, and its softening point is higher than 270°C. It can be used to prepare lithium battery negative electrode materials and as a raw material for the production of high-performance carbon materials, and has a high cost performance; when used to prepare lithium battery negative electrode materials, it can change the appearance structure of the graphite material and change the rate performance of the graphite negative electrode material; it can be used to produce mesophase carbon microspheres and high-performance carbon materials, etc., which can be used in military, medical and aerospace fields, and has a wide range of applications.

[0049] (2) The preparation method of the petroleum-based coated asphalt provided by the present invention is simple, has a short process, and has obvious long-term economic benefits.

[0050] The present invention has been described in detail above, but the above embodiments are merely illustrative in nature and are not intended to limit the present invention. In addition, the present invention is not limited by any theory described in the above prior art or invention summary or the following examples. DETAILED DESCRIPTION

[0051] The present invention will be further described below with reference to the examples. It should be noted that the following examples are provided for illustrative purposes only and do not constitute a limitation on the scope of protection claimed in the present invention.

[0052] Unless otherwise specified, the raw materials, reagents, methods, etc. used in the examples are conventional raw materials, reagents, and methods in the art.

[0053] Ethylene tar is the raw material of carbon black.

[0054] Example 1

[0055] Take 500g of ethylene tar and 500g of N-methyl-2-pyrrolidone and mix them evenly. The temperature is controlled at 50℃, and the temperature is stirred for 30min at a stirring rate of 100r / min. After standing at a constant temperature for 24h, the upper extract is added to a vacuum distillation apparatus. The vacuum degree is controlled at 5Pa, the heating rate is 6℃ / min, the temperature is controlled at 250℃, and the stirring speed is 250r / min. After removing the solvent and light components, ethylene tar pitch is obtained. The ethylene tar pitch is sent to the reactor for oxidation reaction. The temperature is controlled at 280℃, the heating rate is 5℃ / min, the stirring speed is 300r / min, the temperature is maintained for 10h, and the air flow is set to 8m 3 / h, after the reaction is completed, the temperature is lowered to room temperature to obtain coated asphalt.

[0056] Example 2

[0057] Take 500g of ethylene tar and 550g of N-methyl-2-pyrrolidone and mix them evenly. The temperature is controlled at 55℃, and the mixture is stirred at a constant temperature for 40min at a stirring rate of 150r / min. After standing at a constant temperature for 24h, the upper extract is added to a vacuum distillation apparatus. The vacuum degree is controlled at 10Pa, the heating rate is 4℃ / min, the temperature is controlled at 230℃, and the stirring speed is 400r / min. After removing the solvent and light components, ethylene tar pitch is obtained. The ethylene tar pitch is sent to the reactor for oxidation reaction. The temperature is controlled at 330℃, the heating rate is 5℃ / min, the stirring speed is 400r / min, the constant temperature is maintained for 7h, and the air flow is set to 3m 3 / h, after the reaction is completed, the temperature is lowered to room temperature to obtain coated asphalt.

[0058] Example 3

[0059] Take 500g of ethylene tar and 600g of N-methyl-2-pyrrolidone and mix them evenly. The temperature is controlled at 60℃, and the temperature is stirred for 50min at a stirring rate of 150r / min. After standing at a constant temperature for 24h, the upper extract is added to a vacuum distillation apparatus. The vacuum degree is controlled at 5Pa, the heating rate is 6℃ / min, the temperature is controlled at 280℃, and the stirring speed is 500r / min. After removing the solvent and light components, ethylene tar pitch is obtained. The ethylene tar pitch is sent to the reactor for oxidation reaction. The temperature is controlled at 340℃, the heating rate is 5℃ / min, the stirring speed is 200r / min, the temperature is maintained for 10h, and the air flow is set to 5m 3 / h, after the reaction is completed, the temperature is lowered to room temperature to obtain coated asphalt.

[0060] Example 4

[0061] Take 500g of ethylene tar and 400g of N-methyl-2-pyrrolidone and mix them evenly. The temperature is controlled at 65℃, and the temperature is stirred for 60min at a stirring rate of 300r / min. After standing at a constant temperature for 24h, the upper extract is added to a vacuum distillation apparatus. The vacuum degree is controlled at 2Pa, the heating rate is 5℃ / min, the temperature is controlled at 260℃, and the stirring speed is 600r / min. After removing the solvent and light components, ethylene tar pitch is obtained. The ethylene tar pitch is sent to the reactor for oxidation reaction. The temperature is controlled at 350℃, the heating rate is 5℃ / min, the stirring speed is 600r / min, and the temperature is maintained for 10h. The air flow is set to 6m 3 / h, after the reaction is completed, the temperature is lowered to room temperature to obtain coated asphalt.

[0062] Example 5

[0063] Take 500g of ethylene tar and 750g of N-methyl-2-pyrrolidone and mix them evenly. The temperature is controlled at 55℃, and the temperature is stirred for 45min at a stirring rate of 200r / min. After standing at a constant temperature for 24h, the upper extract is added to a vacuum distillation apparatus. The vacuum degree is controlled at 5Pa, the heating rate is 5℃ / min, the temperature is controlled at 240℃, and the stirring speed is 400r / min. After removing the solvent and light components, ethylene tar pitch is obtained. The ethylene tar pitch is sent to the reactor for oxidation reaction. The temperature is controlled at 370℃, the heating rate is 6℃ / min, the stirring speed is 300r / min, the temperature is maintained for 1h, and the air flow is set to 8m 3 / h, after the reaction is completed, the temperature is lowered to room temperature to obtain coated asphalt.

[0064] Example 6

[0065] Take 500g of ethylene tar and 600g of N-methyl-2-pyrrolidone and mix them evenly. The temperature is controlled at 65℃, and the mixture is stirred at a constant temperature for 60min at a stirring rate of 200r / min. After standing at a constant temperature for 24h, the upper extract is added to a vacuum distillation apparatus. The vacuum degree is controlled at 2Pa, the heating rate is 4℃ / min, the temperature is controlled at 280℃, and the stirring speed is 500r / min. After removing the solvent and light components, ethylene tar pitch is obtained. The ethylene tar pitch is sent to the reactor for oxidation reaction. The temperature is controlled at 350℃, the heating rate is 5℃ / min, the stirring speed is 350r / min, the constant temperature is maintained for 7h, and the air flow is set to 10m 3 / h, after the reaction is completed, the temperature is lowered to room temperature to obtain coated asphalt.

[0066] Example 7

[0067] Take 450g of ethylene tar and 600g of N-methyl-2-pyrrolidone and mix them evenly. The temperature is controlled at 65℃, and the temperature is stirred for 60min at a stirring rate of 250r / min. After standing at a constant temperature for 24h, the upper extract is added to a vacuum distillation apparatus. The vacuum degree is controlled at 2Pa, the heating rate is 4℃ / min, the temperature is controlled at 280℃, and the stirring speed is 500r / min. After removing the solvent and light components, ethylene tar pitch is obtained. The ethylene tar pitch is sent to the reactor for oxidation reaction. The temperature is controlled at 380℃, the heating rate is 5℃ / min, the stirring speed is 400r / min, the constant temperature is maintained for 7h, and the air flow is set to 10m 3 / h, after the reaction is completed, the temperature is lowered to room temperature to obtain coated asphalt.

[0068] Comparative Example 1

[0069] Take 500g of ethylene tar and 600g of N-methyl-2-pyrrolidone and mix them evenly. The temperature is controlled at 65℃, and the stirring speed is 200r / min. After standing at the constant temperature for 24h, the upper extract is taken and sent to the reactor for oxidation reaction. The temperature is controlled at 350℃, the heating rate is 5℃ / min, the stirring speed is 350r / min, and the constant temperature is maintained for 7h. The air flow is set to 10m 3 / h, after the reaction is completed, the temperature is lowered to room temperature to obtain coated asphalt.

[0070] Comparative Example 2

[0071] Take 500g of ethylene tar and add it to the vacuum distillation apparatus. The vacuum degree is controlled at 2Pa, the heating rate is 4℃ / min, the temperature is controlled at 280℃, and the stirring speed is 500r / min. After removing the light components, ethylene tar pitch is obtained. The ethylene tar pitch is sent to the reactor for oxidation reaction. The temperature is controlled at 350℃, the heating rate is 5℃ / min, the stirring speed is 350r / min, and the constant temperature is maintained for 7h. The air flow is set to 10m 3 / h, after the reaction is completed, the temperature is lowered to room temperature to obtain coated asphalt.

[0072] Test Trial

[0073] Test standard:

[0074] Asphalt softening point: GB / T 4507-2014;

[0075] Coking value: GB / T 8727-2008;

[0076] Quinoline insoluble matter: GB / T 2293-2019;

[0077] Ash content: SH / T 0422-2000.

[0078] The parameters of the coated asphalt of the embodiment and comparative example are shown in Table 1.

[0079] Table 1

[0080] sample Asphalt softening point / ℃ Coking value / % Quinoline insoluble matter / % Ash / % Example 1 270.1 68.3 0.049 0.12 Example 2 273.4 69.3 0.073 0.12 Example 3 271.9 68.5 0.056 0.12 Example 4 274.1 69.4 0.079 0.12 Example 5 275.2 69.5 0.088 0.12 Example 6 276.3 69.9 0.094 0.12 Example 7 278.1 70.4 0.095 0.12 Comparative Example 1 240.2 63.9 28.3 0.12 Comparative Example 2 253.6 67.2 13.1 0.12

[0081] The above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features thereof may be replaced with equivalents, without departing from the spirit and substance of the claims of the present invention; and such modifications or replacements remain within the scope of the claims of the present invention.

Claims

1. A method for preparing petroleum-based coated asphalt, characterized in that: The following steps are involved: S1, mixing the raw material ethylene tar with an extractant for extraction to obtain an upper aromatic oil-rich extract; S2, subjecting the aromatics-rich oil extract to vacuum distillation to remove the solvent and light components therein to obtain ethylene tar pitch; S3. The ethylene tar pitch is subjected to oxidation reaction to obtain a petroleum-based coated asphalt.

2. The preparation method according to claim 1, characterized in that: The extractant in step S1 is N-methyl-2-pyrrolidone.

3. The preparation method according to claim 1, characterized in that: In step S1, the mass ratio of ethylene tar to extractant is 1:(0.8-1.5).

4. The preparation method according to claim 1, characterized in that: The conditions for extraction in step S1 are as follows: The extraction temperature is 50-65°C, and / or The stirring speed during extraction is 100-300 r / min, and / or The stirring time is 30 to 60 minutes, and then the mixture is allowed to stand at a constant temperature.

5. The preparation method according to claim 1, characterized in that: The conditions of step S2 vacuum distillation are as follows: The distillation temperature is 220-280°C, and / or Heating rate 4~6℃ / min, and / or The stirring speed during distillation is 100-600 r / min, and / or The vacuum degree is 2~10Pa.

6. The preparation method according to claim 1, characterized in that: The oxidation reaction in step S3 is carried out in the presence of air under the following conditions: The reaction temperature is 280-380°C, and / or Heating rate 4~6℃ / min, and / or The reaction time is 1 to 10 hours, and / or The stirring speed during the reaction is 100 to 600 r / min, and / or Air flow rate: 1~10m 3 / h.

7. A petroleum-based coated asphalt, characterized in that: Prepared by the preparation method according to any one of claims 1 to 6; the petroleum-based coated asphalt has the following characteristics: The softening point is not less than 270°C; the quinoline insoluble matter is less than 0.1%; the coking value is not less than 65%; and the ash content is less than 0.2%.

8. Use of the petroleum-based coated asphalt according to claim 7 in preparing negative electrode materials for lithium batteries.

9. The use according to claim 8, characterized in that: The negative electrode material of the lithium battery is natural graphite, artificial graphite or silicon-based material.

10. The use according to claim 9, characterized in that: The lithium battery negative electrode material is used in power batteries, energy storage batteries or new energy vehicles.