A method for preparing a composite for treating acrylonitrile production wastewater

Abstract

This invention discloses a method for preparing a composite for treating acrylonitrile production wastewater, comprising: dispersing an oxidant in an aqueous solution, then adding graphite material, heating the system and stirring to react, maintaining the temperature after the reaction, adding an aqueous solution of β-glycerophosphate and stirring until homogeneous, then naturally cooling to room temperature, allowing it to stand, removing the graphite material, and performing conventional washing, drying, and pulverizing to obtain modified graphite powder with a particle size of 200-400 mesh; dissolving a polyol in water, then heating to a certain temperature, adding N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine and stirring, then adding polyacrylamide until completely dissolved, then adding the modified graphite powder obtained above and stirring until homogeneous, maintaining the temperature and reacting under ultraviolet light, and cooling to room temperature after the reaction to obtain the final product. The composite of this invention can effectively treat pollutants in wastewater, and the process is simple and low-cost.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, and more specifically, relates to a method for preparing a complex for treating acrylonitrile production wastewater. Background Technology

[0002] Acrylonitrile is a colorless, bitter almond-scented, highly toxic organic cyanide, a common chemical raw material widely used in chemical synthesis and other fields, and also an important intermediate in pharmaceuticals and pesticides. Acrylonitrile possesses high toxicity and potential genotoxicity, making it a significant hazardous pollutant in the environment. It not only damages aquatic ecosystems but also endangers human health. Acrylonitrile is a major raw material in the synthetic fiber, synthetic resin, synthetic rubber, and organic synthesis industries, primarily used in the production of acrylic fibers, nitrile rubber, adiponitrile, acrylamide, and ABS resin. With the continuous growth of acrylonitrile production capacity, the volume of acrylonitrile production wastewater has also increased dramatically. This wastewater is complex in composition, highly toxic, and has poor biodegradability, classifying it as one of the 52 priority controlled toxic chemicals. Therefore, research on acrylonitrile wastewater treatment technologies has become a current research hotspot.

[0003] Common methods for treating acrylonitrile wastewater include distillation, incineration, biological methods, membrane separation, and supercritical water oxidation. Currently, biochemical and incineration methods are relatively mature; however, due to factors such as applicability and energy consumption, they are gradually losing their advantages in the context of increasing environmental awareness both internationally and domestically. Meanwhile, advanced oxidation technologies such as electrochemical oxidation and ozone catalytic oxidation, as well as acrylonitrile wastewater conversion technologies, are increasingly involved in acrylonitrile wastewater treatment. Nevertheless, acrylonitrile producers still need to continuously improve or select more suitable treatment methods in accordance with environmental regulations.

[0004] Chinese invention patent CN201810409298.X discloses a method for treating acrylonitrile wastewater, comprising the following steps: (1) introducing acrylonitrile wastewater for mixing and adjusting the pH value to 6.5–8.5; (2) sending it to an electrocoagulation device for further adjustment; (3) sending it to an air flotation tank for further treatment; (4) continuing treatment using a filter; (5) sending it to an oxidation tank for further oxidation; (6) filtration using an ultrafiltration membrane system; and (7) concentration and separation using a reverse osmosis membrane system. This treatment method has the disadvantages of complex process and high cost. For example, Chinese patent application number CN201310681566.0 discloses a method for treating acrylonitrile wastewater. The process flow of this invention is as follows: (1) Acrylonitrile wastewater first enters a short-cut nitrification-denitrification tank; (2) The effluent from the short-cut nitrification-denitrification tank is divided into two streams, one stream enters an anoxic tank, the mixed liquor from the anoxic tank is returned to the short-cut nitrification-denitrification tank, and the other stream enters a sedimentation tank; (3) Part of the sludge at the bottom of the sedimentation tank is returned to the short-cut nitrification-denitrification tank, and part is discharged as sludge, while the supernatant enters an advanced oxidation tank; (4) The effluent from the advanced oxidation tank enters an aerated biological filter to obtain wastewater that meets the first-class standard of the Integrated Wastewater Discharge Standard GB8978-1996. The disadvantage of this method is that the process is long, and a large amount of carbon source (methanol, ethanol) needs to be added to the anoxic tank to meet the carbon-nitrogen ratio required for denitrification, resulting in high operating costs. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems existing in the prior art and provide a method for preparing a complex for treating acrylonitrile production wastewater. The complex of this invention can effectively treat pollutants in acrylonitrile production wastewater, and the process is simple and low-cost.

[0006] The objective of this invention and the technical problem it solves are achieved by the following technical solutions.

[0007] One aspect of the present invention provides a method for preparing a complex for treating acrylonitrile production wastewater, comprising the following steps:

[0008] The oxidant was dispersed in an aqueous solution, and then graphite material was added. The system was heated to 80-100℃ and stirred at 200-400 rpm for 40-80 min. After the reaction was completed, the temperature was kept constant, and β-glycerophosphate sodium aqueous solution was added and stirred evenly. The mixture was then naturally cooled to room temperature and allowed to stand for 12-36 h. The graphite material was then removed, washed, dried, and pulverized in a conventional manner to obtain modified graphite powder with a particle size of 200-400 mesh.

[0009] Dissolve the polyol in water, then heat to 40-60℃ and add N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine and stir for 20-40 min. Then add polyacrylamide until completely dissolved, and then add the modified graphite powder obtained above and stir evenly. Keep the temperature constant and react under ultraviolet light for 2-5 min. After the reaction is completed, cool to room temperature to obtain the final product.

[0010] Preferably, the oxidant is selected from one or more of ammonium persulfate, aluminum chloride, peracetic acid, hydrogen peroxide, and potassium permanganate.

[0011] Preferably, the graphite material is selected from one or more of graphene, graphene oxide, and graphyne.

[0012] Preferably, the oxidant, graphite material and sodium β-glycerophosphate are in a mass ratio of 0.1-0.5:1:0.05-0.12.

[0013] Preferably, the concentration of the β-glycerophosphate sodium aqueous solution is 60-80%.

[0014] Preferably, the polyol is selected from glucose, xylitol and sorbitol.

[0015] Preferably, the polyol, N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine, and polyacrylamide are added in a mass ratio of 1:0.01-0.03:0.1-0.4.

[0016] Preferably, the modified graphite powder is added at a mass ratio of 0.6-0.8:1 to the polyol.

[0017] Preferably, the ultraviolet light is ultraviolet light with a main wavelength of 300-400nm.

[0018] By employing the above technical solution, the present invention has at least the following advantages: The material of the present invention is a composite material that combines adsorption, chelation, and flocculation properties, exhibiting broad-spectrum pollution removal performance. During use, it can efficiently enrich pollutants in acrylonitrile wastewater, facilitating rapid pollutant removal. Using the composite material of the present invention enables pollutant removal through a simple process, resulting in low cost, high efficiency, and widespread applicability.

[0019] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Detailed Implementation

[0020] To make the technical means, creative features, achieved objectives, and effects of this invention readily understandable, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0021] Example 1:

[0022] A method for preparing a complex for treating acrylonitrile production wastewater includes the following steps:

[0023] 30g of ammonium persulfate was dispersed in an aqueous solution, and then 100g of graphene was added. The system was heated to 90℃ and stirred at 300rpm for 60min. After the reaction was completed, the temperature was kept constant, and 8.5g of 70% sodium β-glycerophosphate aqueous solution was added. After stirring evenly, the mixture was allowed to cool naturally to room temperature and then allowed to stand for 24h. The graphene was then removed, washed, dried and pulverized in a conventional manner to obtain modified graphite powder with a particle size of 200-400 mesh.

[0024] Dissolve 100g of sorbitol in 200mL of water, then heat to 50℃ and add 2g of N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine. Stir for 20-40min, then add 25g of polyacrylamide until completely dissolved. Add the 70g of modified graphite powder obtained above and stir evenly. Keep the temperature constant and react under ultraviolet light with a main wavelength of 350nm for 3.5min. After the reaction is completed, cool to room temperature to obtain the final product.

[0025] Example 2:

[0026] A method for preparing a complex for treating acrylonitrile production wastewater includes the following steps:

[0027] 50g of peracetic acid was dispersed in an aqueous solution, and then 100g of graphyne was added. The system was heated to 100℃ and stirred at 400rpm for 40min. After the reaction was completed, the temperature was kept constant, and 5g of 60% sodium β-glycerophosphate aqueous solution was added. After stirring evenly, the mixture was allowed to cool naturally to room temperature and then allowed to stand for 12h. The graphyne was then removed, washed, dried and pulverized in a conventional manner to obtain modified graphite powder with a particle size of 200-400 mesh.

[0028] Dissolve 100g xylitol in 200mL of water, then heat to 60℃ and add 3g N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine. Stir for 20min, then add 10g polyacrylamide until completely dissolved, and then add 80g of the modified graphite powder obtained above. Stir evenly and keep the temperature constant under ultraviolet light with a main wavelength of 300nm for 2min. After the reaction is completed, cool to room temperature to obtain the final product.

[0029] Example 3:

[0030] A method for preparing a complex for treating acrylonitrile production wastewater includes the following steps:

[0031] 10g of hydrogen peroxide was dispersed in an aqueous solution, and then 100g of graphene oxide was added. The system was heated to 80℃ and stirred at 200rpm for 80min. After the reaction was completed, the temperature was kept constant, and 12g of 80% sodium β-glycerophosphate aqueous solution was added. After stirring evenly, the mixture was allowed to cool naturally to room temperature and then allowed to stand for 36h. The graphene oxide was then removed, washed, dried and pulverized in a conventional manner to obtain modified graphite powder with a particle size of 200-400 mesh.

[0032] Dissolve 100g of glucose in 200mL of water, then heat to 40℃ and add 1-3g of N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine and stir for 40min. Then add 40g of polyacrylamide until completely dissolved, and then add 60g of the modified graphite powder obtained above and stir evenly. Keep the temperature constant and react under ultraviolet light with a main wavelength of 400nm for 5min. After the reaction is completed, cool to room temperature to obtain the final product.

[0033] Example 4:

[0034] A method for preparing a complex for treating acrylonitrile production wastewater includes the following steps:

[0035] 40g of potassium permanganate was dispersed in an aqueous solution, and then 100g of graphene was added. The system was heated to 90℃ and stirred at 300rpm for 70min. After the reaction was completed, the temperature was kept constant, and 8g of 60% sodium β-glycerophosphate aqueous solution was added. After stirring evenly, the mixture was allowed to cool naturally to room temperature and then allowed to stand for 30h. The graphene was then removed, washed, dried and pulverized in a conventional manner to obtain modified graphite powder with a particle size of 200-400 mesh.

[0036] Dissolve 100g of glucose in 200mL of water, then heat to 50℃ and add 2g of N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine. Stir for 20-40min, then add 20g of polyacrylamide until completely dissolved. Add 60g of the modified graphite powder obtained above and stir evenly. Keep the temperature constant and react under ultraviolet light with a main wavelength of 400nm for 3min. After the reaction is completed, cool to room temperature to obtain the final product.

[0037] Comparative Example 1:

[0038] A method for preparing a complex for treating acrylonitrile production wastewater includes the following steps:

[0039] 30g of ammonium persulfate was dispersed in an aqueous solution, and then 100g of graphene was added. The system was heated to 90℃ and stirred at 300rpm for 60min. After the reaction was completed, the temperature was kept constant, and 8.5g of 70% sodium β-glycerophosphate aqueous solution was added. After stirring evenly, the mixture was allowed to cool naturally to room temperature and then allowed to stand for 24h. The graphene was then removed, washed, dried, and pulverized in a conventional manner to obtain a final product with a particle size of 200-400 mesh.

[0040] Comparative Example 2:

[0041] A method for preparing a complex for treating acrylonitrile production wastewater includes the following steps:

[0042] Dissolve 100g of sorbitol in 200mL of water, then heat to 50℃ and add 2g of N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine. Stir for 20-40min, then add 25g of polyacrylamide until completely dissolved. Keep the temperature constant and irradiate under ultraviolet light with a main wavelength of 350nm for 3.5min. After the reaction is completed, cool to room temperature to obtain the final product.

[0043] Application example: Testing the removal of pollutants from acrylonitrile production wastewater by different products.

[0044] Experimental subject: The main water quality characteristics of the wastewater from an acrylonitrile plant are COD 1800 mg / L, ammonia nitrogen 48 mg / L, total nitrogen 237 mg / L, and cyanide 5 mg / L;

[0045] Experimental method: Take 6L of the above wastewater and divide it into 6 groups of 1L each, numbered 1-6. Add the products of Examples 1-4 and Comparative Examples 1-2 to the wastewater of the 6 groups at a rate of 20g / L of wastewater. Stir at 200rpm for 15min and let stand for 1h. Take the supernatant and test the water quality pollutant index of each group. The statistical results are shown in Table 1.

[0046] Table 1 Summary of pollutant removal from acrylonitrile production wastewater by different products

[0047]

[0048]

[0049] As can be seen from the results in Table 1, compared with comparative examples 1-2 (corresponding to numbers 5-6), the products of examples 1-4 of the present invention (corresponding to numbers 1-4) can effectively remove pollutants from wastewater, resulting in a significant improvement in the quality of the final effluent.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the methods and techniques disclosed above without departing from the scope of the present invention to create equivalent embodiments. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing a complex for treating acrylonitrile production wastewater, characterized in that, Includes the following steps: The oxidant was dispersed in an aqueous solution, and then graphite material was added. The system was heated to 80-100℃ and stirred at 200-400 rpm for 40-80 min. After the reaction was completed, the temperature was kept constant, and β-glycerophosphate sodium aqueous solution was added and stirred evenly. The mixture was then naturally cooled to room temperature and allowed to stand for 12-36 h. The graphite material was then removed, washed, dried, and pulverized in a conventional manner to obtain modified graphite powder with a particle size of 200-400 mesh. Dissolve the polyol in water, then heat to 40-60℃ and add N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine and stir for 20-40 min. Then add polyacrylamide until completely dissolved, and then add the modified graphite powder obtained above and stir evenly. Keep the temperature constant and react under ultraviolet light for 2-5 min. After the reaction is completed, cool to room temperature to obtain the final product. The oxidant is selected from one or more of ammonium persulfate, peracetic acid, hydrogen peroxide, and potassium permanganate; The graphite material is selected from one or more of graphene, graphene oxide, and graphyne. The polyol is selected from one of glucose, xylitol and sorbitol; The ultraviolet light used is ultraviolet light with a main wavelength of 300-400nm.

2. The preparation method according to claim 1, characterized in that, The oxidant, graphite material, and sodium β-glycerophosphate are prepared in a mass ratio of 0.1-0.5:1:0.05-0.

12.

3. The preparation method according to claim 1, characterized in that, The concentration of the sodium β-glycerophosphate aqueous solution is 60-80%.

4. The preparation method according to claim 1, characterized in that, The polyol, N1,N2-bis(2,3-dihydroxy-4,6-disulfonic acid benzyl)ethylenediamine, and polyacrylamide are added in a mass ratio of 1:0.01-0.03:0.1-0.

4.

5. The preparation method according to claim 1, characterized in that, The modified graphite powder is added at a mass ratio of 0.6-0.8:1 to the polyol.

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