Method for preparing waste resin-based carbon spheres by one-step method, prepared carbon spheres and application

Abstract

The invention discloses a method for preparing waste resin-based carbon spheres through a one-step method, the carbon spheres prepared through the method and application of the carbon spheres. Comprising the following steps: placing waste resin in a reaction furnace, and carbonizing in an inert gas atmosphere to obtain the waste resin-based carbon spheres. According to the preparation method of the resin-based carbon spheres, the waste resin is adopted as a precursor, the steps of a conventional carbon sphere preparation process in the prior art are simplified, the high carbon sphere recovery rate is still obtained, the production cost is greatly reduced, and a new technical scheme is provided for recycling of the waste resin.

Description

Technical Field

[0001] The present application relates to a one-step method for preparing waste resin-based carbon spheres, the prepared carbon spheres and their application, and belongs to the field of resin material recycling. Background Art

[0002] Resin is one of the important raw materials for spherical carbon. Resin has been widely used in various industries, and a large amount of waste resin is also generated every year. These waste resins are very stable and difficult to degrade. Their impact on the environment has attracted widespread attention. The recycling of waste resin also plays an important role in resource utilization. Waste resin recycling can turn these wastes into new resources and process them into new products again, which can save raw materials and costs. This can not only reduce the consumption of natural resources, but also realize the recycling of resources, thereby achieving sustainable development.

[0003] The advantage of phenolic resin recycling is "resource reuse", which can not only reduce environmental pollution, but also save raw materials, reduce production costs and improve economic benefits. There are two main ways to recycle phenolic resin: mechanical recycling and chemical recycling. Mechanical recycling is to use special recycling equipment to crush, screen, wash and other treatments of discarded phenolic products to obtain recycled particles, which are then used to produce new phenolic products. This method is suitable for phenolic products with large recycling volume and low quality requirements, such as waste furniture and building materials. Chemical recycling is to chemically decompose discarded phenolic products to obtain raw materials and recycled particles, which are then used to produce new phenolic products. This method is suitable for phenolic products with small recycling volume and high quality requirements, such as electronic products and auto parts.

[0004] Phenolic resin is one of the important raw materials for carbon spheres. How to use waste phenolic resin to prepare carbon spheres with high recovery rate and low cost is an unresolved problem. Summary of the invention

[0005] The present application creatively utilizes waste resin to prepare carbon spheres with high recovery rate and low cost by selecting waste resin and controlling its water content through only one carbonization step.

[0006] According to one aspect of the present application, a one-step method for preparing waste resin-based carbon spheres is provided, comprising the following steps:

[0007] The waste resin is pretreated and placed in a reaction furnace for carbonization under an inert gas atmosphere to obtain waste resin-based carbon balls;

[0008] Optionally, the pretreatment includes: screening, washing, and airing / baking until the water content of the waste resin is ≤0.05wt%.

[0009] The raw material pretreatment method of waste resin-based carbon balls can be carried out by drying or baking. The specific steps are as follows: 1. Collect the waste recycled phenolic resin, and conduct preliminary screening and cleaning to remove impurities and dirt. 2. Dry or bake the cleaned resin to remove moisture. The drying time and temperature need to be determined according to the type and water content of the resin, and generally take several days to several weeks. 3. The resin after drying or baking needs to be quality tested to ensure that its water content meets the requirements of subsequent processing and utilization.

[0010] Optionally, the water removal treatment further includes an etherification reaction or an esterification reaction.

[0011] Optionally, the waste resin is selected from at least one of styrene resin, acrylic resin and phenolic resin.

[0012] Optionally, the inert gas atmosphere is selected from at least one of nitrogen, argon and helium;

[0013] Optionally, the flow rate of the inert gas atmosphere is 100 to 1000 ml / min.

[0014] Optionally, the flow rate of the inert gas atmosphere is selected from any value of 100 ml / min, 200 ml / min, 300 ml / min, 400 ml / min, 500 ml / min, 600 ml / min, 700 ml / min, 800 ml / min, 900 ml / min, 1000 ml / min, or any range therebetween.

[0015] Optionally, the carbonization temperature is 600-1200°C.

[0016] Optionally, the carbonization temperature is selected from any value of 600°C, 700°C, 800°C, 900°C, 1000°C, 1100°C, 1200°C, or any range therebetween.

[0017] Optionally, the heating rate of the carbonization is 1 to 5°C / min.

[0018] Optionally, the heating rate of the carbonization is selected from any value of 1°C / min, 2°C / min, 3°C / min, 4°C / min, 5°C / min, or any range therebetween.

[0019] Optionally, the carbonization time is 0.1 to 10 hours.

[0020] Optionally, the carbonization time is selected from any value of 0.1h, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, or any range therebetween.

[0021] Optionally, the recovery rate of the waste resin-based carbon balls is 10-60%.

[0022] Optionally, the recovery rate of the waste resin-based carbon balls is 30-40%.

[0023] According to another aspect of the present application, there is provided a waste resin-based carbon sphere obtained by the above method.

[0024] Optionally, the specific surface area of ​​the waste resin-based carbon spheres is 250 to 2000 cm 2 / g.

[0025] Optionally, the specific surface area of ​​the waste resin-based carbon spheres is 250 cm 2 / g、500cm 2 / g、700cm 2 / g、1000cm 2 / g、1500cm 2 / g、2000cm 2 / g, or any range of values ​​in between.

[0026] Optionally, the pore volume of the waste resin-based carbon sphere is 0.1 to 0.9 cm 3 / g.

[0027] Optionally, the particle size of the waste resin-based carbon spheres is 5 to 500 μm.

[0028] According to another aspect of the present application, there is provided an application of the above-mentioned waste resin-based carbon balls for removing organic matter from wastewater.

[0029] According to another aspect of the present application, an application of the above-mentioned waste resin-based carbon spheres is provided for the cyclic adsorption and desorption of small molecule acids, high-salt wastewater pollutants, levofloxacin and other antibiotic substances.

[0030] Desorption can be carried out by using 2% to 6% NaOH solution, heating or re-thermal decomposition.

[0031] The beneficial effects of this application include:

[0032] The present invention develops a method for preparing resin-based carbon spheres, which uses waste resin as a precursor and omits the pre-oxidation and activation steps of the conventional carbon sphere preparation process in the prior art, while still obtaining a good specific surface area, pore volume and a high carbon sphere recovery rate, and greatly reducing the production cost, providing a new technical solution for the recycling and reuse of waste resins. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a SEM scanning electron microscope image of the carbon sphere product in Example 1, with a scale of 1 μm. DETAILED DESCRIPTION

[0034] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0035] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0036] Example 1

[0037] The waste styrene resin is dehydrated: preliminary screening and cleaning are performed to remove impurities and dirt, and then the cleaned resin is baked to a water content of ≤0.05wt% to obtain a waste styrene resin precursor, which is placed in a horizontal converter and carbonized at 900°C for 5h in a nitrogen atmosphere with a nitrogen flow rate of 500mL / min and a heating rate of 2.5°C / min. Waste resin-based carbon balls are obtained by a one-step reaction, and the recovery rate of the waste resin-based carbon balls is 33%.

[0038] Figure 1 This is the SEM image of the carbon ball product in Example 1, with a scale of 1 μm. The specific surface area is 500 m 2 / g; pore volume is 0.2cm 3 / g.

[0039] Comparative Example 1

[0040] Take the same waste styrene resin precursor as in Example 1, place it in a horizontal converter, pre-oxidize it in air at 300°C for 10h, with an air flow rate of 500mL / min and a heating rate of 2.5°C / min to obtain a pre-oxidized resin; continue to carbonize the pre-oxidized resin obtained in the above steps in a horizontal converter under a nitrogen atmosphere at 900°C for 5h, with a nitrogen flow rate of 500mL / min and a heating rate of 2.5°C / min to obtain a carbonized sphere, and then place the waste resin-based carbon sphere in a vertical tubular furnace under a nitrogen atmosphere at 350°C for water vapor activation, with a nitrogen flow rate of 500mL / min, a water inlet flow rate of 0.5g / min, and a heating rate of 5°C / min to obtain the activated waste resin-based carbon sphere. After testing, the results are consistent with the carbon sphere product obtained in Example 1, and the recovery rate, specific surface area, and pore volume of the waste resin-based carbon sphere obtained are similar to those of Example 1.

[0041] 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 one-step method for preparing waste resin-based carbon spheres, characterized in that: The following steps are involved: The waste resin is pretreated and placed in a reaction furnace for carbonization under an inert gas atmosphere to obtain waste resin-based carbon balls; The pretreatment includes: screening, washing, and airing / baking until the water content of the waste resin is ≤0.05wt%.

2. The method according to claim 1, characterized in that The waste resin is selected from at least one of styrene resin, acrylic resin and phenolic resin.

3. The method according to claim 1, characterized in that: The inert gas atmosphere is selected from at least one of nitrogen, argon and helium; Preferably, the flow rate of the inert gas atmosphere is 100-1000 ml / min.

4. The method according to claim 1, characterized in that: The carbonization temperature is 600-1200°C; The heating rate of the carbonization is 1 to 5°C / min; The carbonization time is 0.1 to 10 hours.

5. The method according to claim 1, characterized in that The recovery rate of the waste resin-based carbon balls is 10-60%.

6. A waste resin-based carbon ball, characterized in that: It is obtained by the method according to any one of claims 1 to 5.

7. The waste resin-based carbon sphere according to claim 6, characterized in that: The specific surface area of ​​the waste resin-based carbon spheres is 250 to 2000 cm 2 / g.

8. The waste resin-based carbon sphere according to claim 7, characterized in that: The pore volume of the waste resin-based carbon spheres is 0.1 to 0.9 cm 3 / g.

9. An application of waste resin-based carbon spheres according to any one of claims 6 to 8, characterized in that: Used to remove organic matter from wastewater.

10. An application of waste resin-based carbon spheres according to any one of claims 6 to 8, characterized in that: Used for cyclic adsorption and desorption of small molecule acids, high-salt wastewater pollutants, and antibiotic substances.

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