Spherical activated carbon prepared from waste resin and preparation method of spherical activated carbon

Abstract

The invention discloses spherical activated carbon prepared from waste resin and a preparation method of the spherical activated carbon. Comprising the following steps: mixing waste ion exchange resin with an aqueous solution containing a polyhydroxy compound and soluble salt, drying, carbonizing, pickling, and washing to obtain the spherical activated carbon. The preparation process is simple, and the waste resin solid waste is converted into the high-value spherical activated carbon through one-step modification.

Description

Technical Field

[0001] The present application relates to a spherical activated carbon prepared by using waste resin and a preparation method thereof, belonging to the field of material preparation. Background Art

[0002] Adsorption separation materials are polymer materials that achieve the functions of separation, purification, concentration, enrichment, etc. of substances through ion exchange and adsorption of the exchanged substances. They are widely used in industrial water treatment, food and drinking water, nuclear industry, electronics, biomedicine, environmental protection, hydrometallurgy and other industrial fields. At present, the widely used adsorption separation materials mainly include ion exchange resins, adsorption resins, chelating resins, enzyme carrier resins, etc.

[0003] Ion exchange resins were first used in the field of industrial water treatment. After decades of development, ordinary industrial water treatment has become a standard field with large resin usage and mature applications. At present, ion exchange and adsorption resins still account for about 70% of the application field of ordinary industrial water treatment. Ion exchange and adsorption resins are widely used in the field of ordinary industrial water treatment, mainly because the impurity ions in the water will generate insoluble substances such as calcium carbonate, calcium sulfate, magnesium hydroxide and magnesium silicate at high temperatures, which will be deposited on the heating surface of the boiler to form scale, causing bulges and holes on the heating surface, leading to the rupture of the boiling tube and the vertical color tube, which will not only endanger the safe operation of the boiler, but also increase the maintenance cost of the boiler. Therefore, the water entering the boiler must be free of impurity cations and anions in the water.

[0004] In 2021, my country's ion exchange resin production capacity was 470,000 tons, and output was 356,000 tons, a year-on-year increase of 7.6%. Imports were 18,000 tons, a year-on-year increase of 10.8%. Exports were 129,000 tons, a year-on-year increase of 13.7%. The domestic apparent consumption of ion exchange resin was 245,000 tons, a year-on-year increase of 4.8%.

[0005] However, used ion exchange resins become hazardous solid wastes due to the presence of organic matter or heavy metal ions. The traditional treatment methods for this type of solid waste are incineration or landfill, but this can easily cause secondary pollution and result in a large amount of resource waste. Therefore, it is of great significance to effectively transform waste ion exchange resins into resources. Summary of the invention

[0006] According to one aspect of the present application, a method for preparing spherical activated carbon using waste resin is provided, in which waste ion exchange resin solid waste is converted into high-value spherical activated carbon through a one-step modification, thereby solving the problem in the prior art that the traditional treatment method of ion exchange resin solid waste incineration or landfill easily causes secondary pollution and results in a large amount of waste of resources.

[0007] This application adopts the following technical solutions:

[0008] A method for preparing spherical activated carbon using waste resin comprises the following steps:

[0009] The waste ion exchange resin is mixed with an aqueous solution containing polyhydroxy compounds and soluble salts, dried, and carbonized to obtain a spherical activated carbon precursor;

[0010] The spherical activated carbon precursor is acid-washed and water-washed to obtain the spherical activated carbon.

[0011] Optionally, the waste ion exchange resin is selected from at least one of waste sulfonic acid ion exchange resin, waste carboxylic acid ion exchange resin and waste quaternary ammonium salt ion exchange resin.

[0012] Optionally, the polyol is selected from at least one of glucose, sucrose, glycerol, sorbitol, and ascorbic acid;

[0013] The content of the polyhydroxy compound in the aqueous solution is 5 to 50 wt %.

[0014] The content of the polyhydroxy compound in the aqueous solution is selected from any value of 5wt%, 10wt%, 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 4wt%, 45wt%, 50wt%, or any range therebetween.

[0015] Optionally, the soluble salt is selected from at least one of zinc chloride, zinc sulfate, sodium chloride, sodium sulfate, magnesium chloride, magnesium sulfate, potassium carbonate, and potassium sulfate;

[0016] The content of soluble salt in the aqueous solution is 1-20 wt %.

[0017] The content of soluble salt in the aqueous solution is selected from any value of 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 10wt%, 15wt%, 20wt%, or any range therebetween.

[0018] Optionally, the solid-liquid mass ratio of the waste ion exchange resin to the aqueous solution containing polyhydroxy compounds and soluble salts is 0.1 to 2:1.

[0019] Optionally, the solid-liquid mass ratio of the waste ion exchange resin to the aqueous solution containing polyhydroxy compounds and soluble salts is selected from any value of 0.1:1, 0.2:1, 0.3:1, 0.41, 0.5:1, 1:1, 1.5:1, 2:1, or any range between the two.

[0020] Optionally, the drying conditions include: a temperature of 80 to 180° C. and a time of 1 to 24 hours.

[0021] Optionally, the carbonization conditions include:

[0022] The carbonization is carried out in an inert gas atmosphere, the carbonization temperature is 500 to 1200°C, and the carbonization time is 1 to 12 hours.

[0023] Optionally, the inert gas atmosphere is selected from at least one of nitrogen, argon and helium.

[0024] Optionally, the carbonization temperature is selected from any value of 500°C, 600°C, 700°C, 800°C, 900°C, 1000°C, 1100°C, 1200°C, or any range therebetween.

[0025] Optionally, the pickling conditions include: a temperature of 0 to 150°C.

[0026] Optionally, the pickling conditions include: a temperature of any value among 0°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 50°C, or any range therebetween.

[0027] The pickling acid is selected from at least one of hydrochloric acid, nitric acid, sulfuric acid, acetic acid and chloroacetic acid.

[0028] Optionally, in the acid washing, the weight ratio of the spherical activated carbon precursor to the acid is 1:1-5.

[0029] According to another aspect of the present application, there is also provided a spherical activated carbon prepared by the above method, wherein the particle size of the spherical activated carbon is 0.1 to 1.2 mm;

[0030] The specific surface area of ​​the spherical activated carbon is 500 to 1500 m 2 / g.

[0031] The beneficial effects of this application include:

[0032] The preparation process is simple, and the discarded ion exchange resin solid waste is converted into high-value spherical activated carbon with a good specific surface area through a one-step modification. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a physical picture of the spherical activated carbon obtained in Example 1.

[0034] Figure 2 This is the nitrogen physical adsorption curve of the spherical activated carbon obtained in Example 1. DETAILED DESCRIPTION

[0035] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0036] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0037] Example 1

[0038] S1: Dissolve 10 g glucose and 5 g anhydrous sodium chloride in 20 mL deionized water to obtain a homogeneous transparent solution;

[0039] S2: 20 g of waste carboxylic acid type ion exchange resin was fully mixed with the solution obtained in S1, and then dried at 120° C. to obtain modified waste resin dry balls;

[0040] S3: The modified waste resin dry ball is placed in a nitrogen atmosphere, heated to 600°C, and kept at this temperature for 2 hours to obtain a spherical activated carbon precursor;

[0041] S4: The spherical activated carbon precursor was washed twice with 10% HCl solution at 60° C., then washed with deionized water until neutral, and dried at 120° C. to obtain spherical activated carbon.

[0042] Figure 1 This is a physical picture of the spherical activated carbon obtained in Example 1. Figure 2 This is the nitrogen physical adsorption curve of the spherical activated carbon obtained in Example 1.

[0043] The average particle size of the spherical activated carbon obtained was 0.68 mm and the specific surface area was 1079 m 2 / g.

[0044] Embodiments 2 to 5

[0045] The method is basically the same as Example 1, except that the glucose in S1 is replaced by sucrose, glycerol, sorbitol and ascorbic acid in sequence, and the rest is exactly the same as Example 1.

[0046] The average particle size of the spherical activated carbon obtained in Examples 2 to 5 is 0.72 mm, and the specific surface area is 1055 m 2 / g.

[0047] Embodiment 6-7

[0048] The method is basically the same as Example 1, except that the sodium chloride in S1 is replaced by zinc sulfate and potassium carbonate in sequence, and the rest is exactly the same as Example 1.

[0049] The average particle size of the spherical activated carbon obtained in Examples 6 and 7 is 0.75 mm and 0.70 mm, respectively, and the specific surface area is 988 m 2 / g and 1231m 2 / g.

[0050] Example 8

[0051] It is basically the same as Example 1, except that the amount of glucose in S1 is adjusted to 20 g, and the rest is exactly the same as Example 1.

[0052] The average particle size of the spherical activated carbon obtained was 0.83 mm and the specific surface area was 1038 m 2 / g.

[0053] Example 9

[0054] The method is basically the same as Example 1, except that the amount of sodium chloride in S1 is adjusted to 1 g, and the rest is exactly the same as Example 1.

[0055] The average particle size of the spherical activated carbon obtained was 0.65 mm and the specific surface area was 635 m 2 / g.

[0056] Embodiments 10 to 11

[0057] The method is basically the same as Example 1, except that the waste carboxylic acid ion exchange resin in S2 is replaced by waste sulfonic acid ion exchange resin and waste quaternary ammonium salt ion exchange resin in sequence, and the rest is exactly the same as Example 1.

[0058] The average particle sizes of the spherical activated carbons obtained were 1.16 mm and 0.42 mm, respectively, and their specific surface areas were 1228 m 2 / g and 774m 2 / g.

[0059] Example 12

[0060] The method is basically the same as Example 1, except that the amount of waste ion exchange resin in S2 is adjusted to 40 g, and the rest is exactly the same as Example 1.

[0061] The average particle size of the spherical activated carbon obtained was 0.60 mm and the specific surface area was 856 m 2 / g.

[0062] Embodiment 13

[0063] It is basically the same as Example 1, except that the carbonization temperature in S3 is adjusted to 1000° C., and the rest is exactly the same as Example 1.

[0064] The average particle size of the spherical activated carbon obtained was 0.58 mm and the specific surface area was 1483 m 2 / g.

[0065] Embodiment 14

[0066] The method is basically the same as Example 1, except that the HCl in S4 is adjusted to chloroacetic acid, and the rest is exactly the same as Example 1.

[0067] The average particle size of the spherical activated carbon obtained was 0.70 mm and the specific surface area was 1091 m 2 / g.

[0068] Embodiment 15

[0069] The process is basically the same as Example 1, except that the pickling temperature in S4 is adjusted to 0°C, and the rest is exactly the same as Example 1.

[0070] The average particle size of the spherical activated carbon obtained was 0.66 mm and the specific surface area was 971 m 2 / g.

[0071] Comparative Example 1

[0072] The method is basically the same as Example 1, except that glucose is not added, and the rest is exactly the same as Example 1.

[0073] In Comparative Example 1, no spherical activated carbon was obtained, and only irregular block activated carbon was obtained, with a specific surface area of ​​583 m 2 / g.

[0074] Comparative Example 2

[0075] The method is basically the same as Example 1, except that sodium chloride is not added, and the rest is exactly the same as Example 1.

[0076] The average particle size of the spherical activated carbon obtained was 0.64 mm and the specific surface area was 357 m 2 / g.

[0077] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for preparing spherical activated carbon using waste resin, characterized in that: The steps include: The waste ion exchange resin is mixed with an aqueous solution containing polyhydroxy compounds and soluble salts, dried, and carbonized to obtain a spherical activated carbon precursor; The spherical activated carbon precursor is acid-washed and water-washed to obtain the spherical activated carbon.

2. The method according to claim 1, characterized in that The waste ion exchange resin is selected from at least one of waste sulfonic acid ion exchange resin, waste carboxylic acid ion exchange resin and waste quaternary ammonium salt ion exchange resin.

3. The method according to claim 1, characterized in that The polyol is selected from at least one of glucose, sucrose, glycerol, sorbitol and ascorbic acid; The content of the polyhydroxy compound in the aqueous solution is 5 to 50 wt %.

4. The method according to claim 1, characterized in that The soluble salt is selected from at least one of zinc chloride, zinc sulfate, sodium chloride, sodium sulfate, magnesium chloride, magnesium sulfate, potassium carbonate and potassium sulfate; The content of soluble salt in the aqueous solution is 1-20 wt %.

5. The method according to claim 1, characterized in that The solid-liquid mass ratio of the waste ion exchange resin to the aqueous solution containing polyhydroxy compounds and soluble salts is 0.1-2:

1.

6. The method according to claim 1, characterized in that The drying conditions include: a temperature of 80 to 180° C. and a time of 1 to 24 hours.

7. The method according to claim 1, characterized in that The carbonization conditions include: The carbonization is carried out in an inert gas atmosphere at a temperature of 500 to 1200°C and a carbonization time of 1 to 12 hours; Preferably, the inert gas is selected from at least one of nitrogen, argon and helium.

8. The method according to claim 1, characterized in that: The pickling conditions include: a temperature of 0 to 150°C; The pickling acid is selected from at least one of hydrochloric acid, nitric acid, sulfuric acid, acetic acid and chloroacetic acid.

9. The method according to claim 8, characterized in that In the acid washing, the weight ratio of the spherical activated carbon precursor to the acid is 1:1-5.

10. A spherical activated carbon prepared according to the method according to any one of claims 1 to 9, characterized in that: The particle size of the spherical activated carbon is 0.1 to 1.2 mm; The specific surface area of ​​the spherical activated carbon is 500 to 1500 m 2 / g.

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