A method for removing sodium ions from coal tar

Abstract

The application provides a method for removing sodium ions in coal tar, which comprises the following steps: heating high-temperature coal tar with a sodium ion content of less than or equal to 140 mg / kg to 70-80 DEG C, adding a sodium ion adsorbent, fully stirring the coal tar, then diluting the coal tar after the sodium ions are removed by using soft water, wherein the volume ratio of water to coal tar is not less than 0.5, and after dilution, the sodium ion adsorbent after absorbing sodium ions is removed by filtration; finally, the coal tar dilution liquid after the dilution treatment is subjected to oil-water separation and pressure dewatering treatment, so that the sodium ion content in the coal tar is less than or equal to 40 mg / kg, wherein the sodium ion adsorbent comprises a carbonized phenol formaldehyde resin matrix and a sulfonated polysulfone layer. + The sulfonated polysulfone surface contains a large number of sulfonic acid groups, the sulfonic acid groups are strong water-soluble strong acid groups, and the sulfonic acid groups can be adsorbed with alkali metal ions Na + The reaction occurs to form a sodium sulfonate group, and the adsorption of sodium ions is realized.

Description

Technical Field

[0001] This invention relates to the field of coal tar metal salt ion removal technology, and in particular to a method for removing sodium ions from coal tar. Background Technology

[0002] Carbon-based pitch is obtained by modifying coal tar pitch and is mainly used to prepare mesophase carbon microspheres. Due to their relatively high chemical and thermal stability, mesophase carbon microspheres are widely used in lithium battery anode materials.

[0003] Carbon-based asphalt is a modified version of traditional asphalt. The main factor affecting the quality of carbon-based asphalt is the sodium ion content. The raw material for the industrial production of high-quality carbon-based asphalt is high-temperature coal tar, which contains less than 4% water and 52%-55% asphalt.

[0004] The moisture in high-temperature coal tar contains some metal ions, Na. + Its presence has a significant impact on the quality of asphalt; the higher the moisture content, the greater the ash content of the asphalt. Therefore, to reduce ash content, it is necessary to reduce the Na content in the raw coal tar. + The content of Na in coal tar + When the content is ≤40mg / kg, the Na content in asphalt can be ensured. + Content ≤90mg / kg.

[0005] Patent publication CN113956899A discloses a method for removing impurities from coal tar. The method involves filtering the coal tar through a membrane to remove heavy asphaltene from medium- and low-temperature coal tar, resulting in filtered coal tar. The filtered coal tar is then mixed with a demetallizing agent using a stirring device, causing the metal complexes and organic chlorine compounds in the filtered coal tar to be converted into inorganic salts, obtaining a first mixture. Water is then added to the first mixture, and the mixture is stirred again to transfer the converted inorganic salts from the coal tar to the aqueous phase, obtaining a second mixture. The second mixture is then subjected to a horizontal screw centrifuge for three-phase separation of solids, water, and oil, yielding a solid phase, an aqueous phase, and an oil phase. The oil phase is then filtered through a multi-stage filter to remove residual solid impurities, and finally subjected to centrifugal flash evaporation to remove residual water, thus obtaining the impurity-removed coal tar. This method, which uses a demetallizing agent to separate impurities and centrifugal flash evaporation to remove water, carries the risk of introducing other impurities. Summary of the Invention

[0006] In view of the above problems, this application provides a method for removing sodium ions from coal tar, which can effectively remove sodium ions from coal tar, specifically as follows:

[0007] A method for removing sodium ions from coal tar includes:

[0008] Sodium ion removal: High-temperature coal tar with a sodium ion content ≤140mg / kg is heated to 70℃.

[0009] ~80℃, and add sodium ion adsorbent, stir the coal tar thoroughly, so that the sodium ion adsorbent adsorbs sodium ions in the coal tar;

[0010] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water. After dilution, the sodium ion adsorbent is filtered out.

[0011] Dehydration treatment: The diluted coal tar solution is subjected to oil-water separation and pressurized dehydration treatment to ensure that the sodium ion content in the coal tar is ≤40mg / kg;

[0012] The sodium ion adsorbent comprises: a carbonized phenolic resin matrix, and a sulfonated polysulfone layer on the outer layer of the carbonized phenolic resin matrix, wherein the particle size of the carbonized phenolic resin matrix is ​​≤1 cm, and the mass ratio of the carbonized phenolic resin matrix to the sulfonated polysulfone is 1:0.3 to 0.4.

[0013] In this invention, carbonized phenolic resin has the characteristics of high strength and low density, and carbonized phenolic resin has good compatibility with polymers, so it can be used as a carrier matrix for sulfonated polysulfone.

[0014] The surface of sulfonated polysulfone contains a large number of sulfonic acid groups. Sulfonic acid groups are strongly water-soluble and strongly acidic groups, and they can react with alkali metal ions such as Na+. + The reaction forms sodium sulfonate groups, which adsorb sodium ions.

[0015] Furthermore, the preparation method of the above-mentioned sodium ion adsorbent includes:

[0016] Prepare a sulfonated polysulfone solution with a mass concentration of 5% to 8%;

[0017] After fully dispersing the carbonized phenolic resin matrix in the prepared sulfonated polysulfone solution, removing the excess sulfonated polysulfone solution, and then drying the carbonized phenolic resin coated with sulfonated polysulfone, a carbonized phenolic resin-based sulfonated polysulfone sodium ion adsorbent is obtained.

[0018] Furthermore, the degree of sulfonation of the sulfonated polysulfone is not less than 5%.

[0019] Optionally, the solvent for the sulfonated polysulfone solution is at least one of DMF and DMSO.

[0020] Furthermore, the amount of sodium ion adsorbent added is not less than 0.5% of the total mass of the coal tar dilution solution.

[0021] Furthermore, in the dilution process, the softened water is distilled water or purified water.

[0022] Furthermore, in the dilution process, the volume ratio of water to coal tar is not less than 0.5.

[0023] Furthermore, in the dehydration process, the dehydration pressure of the pressurized dehydration process is not less than 0.2 MPa.

[0024] The beneficial effects of this invention are as follows:

[0025] 1. In this invention, the high strength and low density of carbonized phenolic resin are utilized, and the carbonized phenolic resin has good compatibility with polymers, so it can be used as a carrier matrix for sulfonated polysulfone.

[0026] 2. The surface of sulfonated polysulfone contains a large number of sulfonic acid groups. Sulfonic acid groups are strongly water-soluble and strongly acidic groups. These sulfonic acid groups can react with alkali metal ions such as Na+. + The reaction forms sodium sulfonate groups, which achieve efficient adsorption of sodium ions, thereby realizing the adsorption and removal of sodium ions from coal tar. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] This invention provides a method for removing sodium ions from coal tar, comprising:

[0029] Sodium ion removal: High-temperature coal tar with a sodium ion content ≤140mg / kg is heated to 70℃.

[0030] The coal tar is heated to ~80℃, and sodium ion adsorbent is added. The coal tar is stirred thoroughly so that the sodium ion adsorbent adsorbs sodium ions in the coal tar. The amount of sodium ion adsorbent added shall not be less than 0.5% of the total mass of the coal tar dilution.

[0031] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water, and the volume ratio of water to coal tar is not less than 0.5. After dilution treatment, the sodium ion adsorbent after adsorbing sodium ions is filtered out.

[0032] Dehydration treatment: The diluted coal tar liquid is subjected to oil-water separation and pressure dehydration treatment to ensure that the sodium ion content in the coal tar is ≤40mg / kg, and the dehydration pressure is not less than 0.2MPa.

[0033] The sodium ion adsorbent comprises: a carbonized phenolic resin matrix, and a sulfonated polysulfone layer on the outer layer of the carbonized phenolic resin matrix, wherein the particle size of the carbonized phenolic resin matrix is ​​≤1 cm, and the mass ratio of the carbonized phenolic resin matrix to the sulfonated polysulfone is 1:0.3 to 0.4.

[0034] The sodium ion adsorbent comprises: a carbonized phenolic resin matrix, and a sulfonated polysulfone layer on the outer layer of the carbonized phenolic resin matrix. It should be noted that although the mass ratio of the carbonized phenolic resin matrix to the sulfonated polysulfone cannot be accurately controlled, after the carbonized phenolic resin matrix with a particle size ≤1cm is fully dispersed, the mass ratio of the carbonized phenolic resin matrix to the sulfonated polysulfone is in the range of 1:0.3 to 0.4.

[0035] The preparation method of the above-mentioned sodium ion adsorbent includes:

[0036] Prepare a sulfonated polysulfone solution with a mass concentration of 5% to 8%, wherein the degree of sulfonation of the sulfonated polysulfone is not less than 5%, and the solvent of the sulfonated polysulfone solution is at least one of DMF and DMSO.

[0037] After fully dispersing the carbonized phenolic resin matrix in the prepared sulfonated polysulfone solution, removing the excess sulfonated polysulfone solution, and then drying the carbonized phenolic resin coated with sulfonated polysulfone, a carbonized phenolic resin-based sulfonated polysulfone sodium ion adsorbent is obtained.

[0038] The present invention will be illustrated below through specific embodiments.

[0039] Example 1.1

[0040] The preparation method of sodium ion adsorbent is as follows:

[0041] Five parts of sulfonated polysulfone with a sulfonation degree of 20% were dissolved in 95 parts of DMF solution to obtain a sulfonated polysulfone solution with a mass concentration of 5%.

[0042] Carbonized phenolic resin matrix particles with a particle size of 1 cm were placed in a sulfonated polysulfone solution with a mass concentration of 5% obtained in the above steps and dispersed for 3 minutes. After removing the excess sulfonated polysulfone solution, carbonized phenolic resin coated with sulfonated polysulfone was obtained.

[0043] The carbonized phenolic resin coated with sulfonated polysulfone was dried to obtain a carbonized phenolic resin-based sulfonated polysulfone sodium ion adsorbent.

[0044] Example 1.2

[0045] The preparation method of sodium ion adsorbent is as follows:

[0046] Eight parts of sulfonated polysulfone with a sulfonation degree of 5% were dissolved in 92 parts of DMF solution to obtain a sulfonated polysulfone solution with a mass concentration of 8%.

[0047] Carbonized phenolic resin matrix particles with a particle size of 0.6 cm were placed in a sulfonated polysulfone solution with a mass concentration of 8% obtained in the above steps and dispersed for 4 minutes. After removing the excess sulfonated polysulfone solution, carbonized phenolic resin coated with sulfonated polysulfone was obtained.

[0048] The carbonized phenolic resin coated with sulfonated polysulfone was dried to obtain a carbonized phenolic resin-based sulfonated polysulfone sodium ion adsorbent.

[0049] Example 1.3

[0050] The preparation method of sodium ion adsorbent is as follows:

[0051] Seven parts of sulfonated polysulfone with a sulfonation degree of 10% were dissolved in 93 parts of DMSO solution to obtain a sulfonated polysulfone solution with a mass concentration of 7%.

[0052] Carbonized phenolic resin matrix particles with a particle size of 0.6 cm were placed in a sulfonated polysulfone solution with a mass concentration of 7% obtained in the above steps and dispersed for 3 minutes. After removing the excess sulfonated polysulfone solution, carbonized phenolic resin coated with sulfonated polysulfone was obtained.

[0053] The carbonized phenolic resin coated with sulfonated polysulfone was dried to obtain a carbonized phenolic resin-based sulfonated polysulfone sodium ion adsorbent.

[0054] Example 2.1

[0055] A method for removing sodium ions from coal tar, using the sodium ion adsorbent obtained in Example 1.1, comprising:

[0056] Sodium ion removal: High-temperature coal tar with a sodium ion content of 137 mg / kg was heated to 70℃~80℃, and the sodium ion adsorbent obtained in Example 1.1 was added. The amount of sodium ion adsorbent added was 0.5% of the total mass of coal tar. The coal tar was stirred thoroughly for 5 minutes to allow the sodium ion adsorbent to adsorb sodium ions in the coal tar.

[0057] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water at a volume ratio of 0.5 to 0.5. After dilution, the sodium ion adsorbent is filtered out.

[0058] Dehydration treatment: The diluted coal tar solution was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 27 mg / kg in the coal tar. The dehydration pressure was 0.2 MPa and the dehydration time was 5 min.

[0059] Example 2.2

[0060] A method for removing sodium ions from coal tar, using the sodium ion adsorbent obtained in Example 1.1, comprising:

[0061] Sodium ion removal: High-temperature coal tar with a sodium ion content of 135 mg / kg was heated to 70℃~80℃, and the sodium ion adsorbent obtained in Example 1.1 was added. The amount of sodium ion adsorbent added was 1.0% of the total mass of coal tar. The coal tar was stirred thoroughly for 5 minutes to allow the sodium ion adsorbent to adsorb sodium ions in the coal tar.

[0062] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water at a volume ratio of 0.6 to 0.6. After dilution, the sodium ion adsorbent is filtered out.

[0063] Dehydration treatment: The diluted coal tar liquid was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 16 mg / kg in the coal tar. The dehydration pressure was 0.2 MPa and the dehydration time was 5 min.

[0064] Example 2.3

[0065] A method for removing sodium ions from coal tar, using the sodium ion adsorbent obtained in Example 1.1, comprising:

[0066] Sodium ion removal: High-temperature coal tar with a sodium ion content of 135 mg / kg was heated to 70℃~80℃, and the sodium ion adsorbent obtained in Example 1.1 was added. The amount of sodium ion adsorbent added was 1.3% of the total mass of coal tar. The coal tar was stirred thoroughly for 4 minutes to allow the sodium ion adsorbent to adsorb sodium ions in the coal tar.

[0067] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water at a volume ratio of 0.7 to 0.7. After dilution, the sodium ion adsorbent is filtered out.

[0068] Dehydration treatment: The diluted coal tar liquid was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 15 mg / kg in the coal tar. The dehydration pressure was 0.25 MPa and the dehydration time was 4 min.

[0069] Example 2.4

[0070] A method for removing sodium ions from coal tar, using the sodium ion adsorbent obtained in Example 1.2, comprising:

[0071] Sodium ion removal: High-temperature coal tar with a sodium ion content of 139 mg / kg was heated to 70℃~80℃, and the sodium ion adsorbent obtained in Example 1.2 was added. The amount of sodium ion adsorbent added was 0.5% of the total mass of coal tar. The coal tar was stirred thoroughly for 6 minutes to allow the sodium ion adsorbent to adsorb sodium ions in the coal tar.

[0072] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water at a volume ratio of 0.5 to 0.5. After dilution, the sodium ion adsorbent is filtered out.

[0073] Dehydration treatment: The diluted coal tar liquid was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 39 mg / kg in the coal tar. The dehydration pressure was 0.2 MPa and the dehydration time was 5 min.

[0074] Example 2.5

[0075] A method for removing sodium ions from coal tar, using the sodium ion adsorbent obtained in Example 1.2, comprising:

[0076] Sodium ion removal: High-temperature coal tar with a sodium ion content of 137 mg / kg was heated to 70℃~80℃, and the sodium ion adsorbent obtained in Example 1.2 was added. The amount of sodium ion adsorbent added was 1.0% of the total mass of coal tar. The coal tar was stirred thoroughly for 6 minutes to allow the sodium ion adsorbent to adsorb sodium ions in the coal tar.

[0077] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water at a volume ratio of 0.6 to 0.6. After dilution, the sodium ion adsorbent is filtered out.

[0078] Dehydration treatment: The diluted coal tar liquid was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 35 mg / kg in the coal tar. The dehydration pressure was 0.2 MPa and the dehydration time was 5 min.

[0079] Example 2.6

[0080] A method for removing sodium ions from coal tar, using the sodium ion adsorbent obtained in Example 1.2, comprising:

[0081] Sodium ion removal: High-temperature coal tar with a sodium ion content of 136 mg / kg was heated to 70℃~80℃, and the sodium ion adsorbent obtained in Example 1.2 was added. The amount of sodium ion adsorbent added was 1.3% of the total mass of coal tar. The coal tar was stirred thoroughly for 4 minutes to allow the sodium ion adsorbent to adsorb sodium ions in the coal tar.

[0082] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water at a volume ratio of 0.7 to 0.7. After dilution, the sodium ion adsorbent is filtered out.

[0083] Dehydration treatment: The diluted coal tar solution was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 33 mg / kg in the coal tar. The dehydration pressure was 0.25 MPa and the dehydration time was 4 min.

[0084] Example 2.7

[0085] A method for removing sodium ions from coal tar, using the sodium ion adsorbent obtained in Example 1.3, comprising:

[0086] Sodium ion removal: High-temperature coal tar with a sodium ion content of 137 mg / kg was heated to 70℃~80℃, and the sodium ion adsorbent obtained in Example 1.3 was added. The amount of sodium ion adsorbent added was 0.5% of the total mass of coal tar. The coal tar was stirred thoroughly for 6 minutes to allow the sodium ion adsorbent to adsorb sodium ions in the coal tar.

[0087] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water at a volume ratio of 0.5 to 0.5. After dilution, the sodium ion adsorbent is filtered out.

[0088] Dehydration treatment: The diluted coal tar solution was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 36 mg / kg in the coal tar. The dehydration pressure was 0.2 MPa and the dehydration time was 5 min.

[0089] Example 2.8

[0090] A method for removing sodium ions from coal tar, using the sodium ion adsorbent obtained in Example 1.3, comprising:

[0091] Sodium ion removal: High-temperature coal tar with a sodium ion content of 136 mg / kg was heated to 70℃~80℃, and the sodium ion adsorbent obtained in Example 1.3 was added. The amount of sodium ion adsorbent added was 1.0% of the total mass of coal tar. The coal tar was stirred thoroughly for 5 minutes to allow the sodium ion adsorbent to adsorb sodium ions in the coal tar.

[0092] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water at a volume ratio of 0.5 to 0.5. After dilution, the sodium ion adsorbent is filtered out.

[0093] Dehydration treatment: The diluted coal tar solution was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 23 mg / kg in the coal tar. The dehydration pressure was 0.2 MPa and the dehydration time was 5 min.

[0094] Example 2.9

[0095] A method for removing sodium ions from coal tar, using the sodium ion adsorbent obtained in Example 1.3, comprising:

[0096] Sodium ion removal: High-temperature coal tar with a sodium ion content of 137 mg / kg was heated to 70℃~80℃, and the sodium ion adsorbent obtained in Example 1.3 was added. The amount of sodium ion adsorbent added was 1.3% of the total mass of coal tar. The coal tar was stirred thoroughly for 6 minutes to allow the sodium ion adsorbent to adsorb sodium ions in the coal tar.

[0097] Dilution treatment: The coal tar after sodium ion removal is diluted with softened water at a volume ratio of 0.5 to 0.5. After dilution, the sodium ion adsorbent is filtered out.

[0098] Dehydration treatment: The diluted coal tar solution was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 19 mg / kg in the coal tar. The dehydration pressure was 0.25 MPa and the dehydration time was 4 min.

[0099] Comparative Example 1

[0100] A method for removing sodium ions from coal tar includes:

[0101] Dilution treatment: The high-temperature coal tar with a sodium ion content of 137 mg / kg was heated to 70℃~80℃ and diluted with softened water at a volume ratio of 0.5 for water to coal tar.

[0102] Dehydration treatment: The diluted coal tar solution was subjected to oil-water separation and pressure dehydration treatment to obtain a sodium ion content of 109 mg / kg in the coal tar. The dehydration pressure was 0.2 MPa and the dehydration time was 5 min.

[0103] Table 1 is a comparison table of sodium ion content in coal tar before and after treatment with sodium ion adsorbent in the examples.

[0104] Table 1 Comparison of sodium ion content in coal tar before and after treatment with sodium ion adsorbent in each embodiment.

[0105]

[0106]

[0107] As can be seen from the above examples, the higher the proportion of sulfonated polysulfone in the sodium ion adsorbent, the better the adsorption effect on sodium ions; the higher the degree of sulfonation of the sodium ion adsorbent, the better the adsorption effect on sodium ions; and the higher the proportion of sodium ion adsorbent added to the total mass of coal tar, the better the adsorption effect on sodium ions. It is evident that the surface of sulfonated polysulfone contains a large number of sulfonic acid groups. Sulfonic acid groups are strongly water-soluble and strongly acidic groups, and these groups can react with alkali metal ions such as sodium... + The reaction forms sodium sulfonate groups, achieving efficient adsorption of sodium ions.

[0108] Compared with Comparative Example 1, Example 2.1 of the present invention, using a sodium ion adsorbent, significantly improves dehydration efficiency compared to not using a sodium ion adsorbent. Traditional methods of reducing sodium ion content from 137 mg / kg to 27 mg / kg using water dilution require multiple dilutions and consume at least four times the volume of coal tar in water. In Example 2.1, the volume ratio of water to coal tar is only 0.5.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for removing sodium ions from coal tar, characterized in that, include: Sodium ion removal: High-temperature coal tar with a sodium ion content ≤140mg / kg is heated to 70℃~80℃, and sodium ion adsorbent is added. The coal tar is stirred thoroughly so that the sodium ion adsorbent adsorbs sodium ions in the coal tar. Dilution treatment: The coal tar after sodium ion removal is diluted with softened water. After dilution, the sodium ion adsorbent is filtered out. Dehydration treatment: The diluted coal tar solution is subjected to oil-water separation and pressurized dehydration treatment to ensure that the sodium ion content in the coal tar is ≤40mg / kg; The sodium ion adsorbent comprises: a carbonized phenolic resin matrix, and a sulfonated polysulfone layer on the outer layer of the carbonized phenolic resin matrix, wherein the particle size of the carbonized phenolic resin matrix is ​​≤1 cm, and the mass ratio of the carbonized phenolic resin matrix to the sulfonated polysulfone is 1:0.3 to 0.

4.

2. The method for removing sodium ions from coal tar according to claim 1, characterized in that, The preparation method of the sodium ion adsorbent includes: Prepare a sulfonated polysulfone solution with a mass concentration of 5% to 8%; After fully dispersing the carbonized phenolic resin matrix in the prepared sulfonated polysulfone solution, removing the excess sulfonated polysulfone solution, and then drying the carbonized phenolic resin coated with sulfonated polysulfone, a carbonized phenolic resin-based sulfonated polysulfone sodium ion adsorbent is obtained.

3. The method for removing sodium ions from coal tar according to claim 1 or 2, characterized in that, The degree of sulfonation of the sulfonated polysulfone is not less than 5%.

4. The method for removing sodium ions from coal tar according to claim 2, characterized in that, The solvent for the sulfonated polysulfone solution is at least one of DMF and DMSO.

5. The method for removing sodium ions from coal tar according to claim 1, characterized in that, In the dilution process, the amount of sodium ion adsorbent added is not less than 0.5% of the total mass of the coal tar dilution solution.

6. The method for removing sodium ions from coal tar according to claim 1, characterized in that, The softened water used in the dilution process is either distilled water or purified water.

7. The method for removing sodium ions from coal tar according to claim 1, characterized in that, In the dilution process, the volume ratio of water to coal tar is not less than 0.

5.

8. The method for removing sodium ions from coal tar according to claim 1, characterized in that, In the dehydration process, the dehydration pressure of the pressurized dehydration process is not less than 0.2 MPa.

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