A wastewater treatment process for the continuous production of chloropropargyl

Abstract

The application provides a wastewater treatment process for continuously producing chloropropargyl, and belongs to the technical field of wastewater treatment.The process adds 4-4.5 g of oxidized flaky graphite-modified activated carbon into 1 L of wastewater, the temperature of the wastewater is 45-50 DEG C, and the adsorption time is 45-55 min.The preparation method of the oxidized flaky graphite-modified activated carbon comprises the following steps: A1, preparing modified activated carbon;pretreating activated carbon to obtain pretreated activated carbon, and then modifying the pretreated activated carbon by using ammonia water to obtain modified activated carbon;A2, preparing oxidized flaky graphite;oxidizing flaky graphite by using concentrated sulfuric acid and concentrated nitric acid to obtain oxidized flaky graphite;A3, mixing the modified activated carbon and the oxidized flaky graphite according to a mass ratio of (3-3.5):1, and ball milling, so as to obtain the oxidized flaky graphite-modified activated carbon.The application can effectively improve the adsorption rate and adsorption capacity of DMF when the temperature of the wastewater is higher than 45 DEG C (45-50 DEG C).

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to a wastewater treatment process for continuous production of chloropropyne. Background Technology

[0002] In the production of chloropropyne, thionyl chloride and DFM catalyst are pumped into a mixer and mixed. Then, they are mixed thoroughly with propynyl alcohol pumped into a reactor, and the reaction is heated. The mixture is then reacted and matured under suitable temperature and pressure conditions. Finally, the continuous reaction solution is cooled by a condenser. The crude product is stripped to remove light components, yielding chloropropyne. The chloropropyne product is then washed with water and distilled to obtain pure chloropropyne. Specifically, thionyl chloride and DFM are removed from the chloropropyne through water washing. The resulting wastewater contains 0.5%-5% DFM. Because DFM is toxic and pollutes the environment, this wastewater cannot be directly discharged and requires treatment.

[0003] Existing methods for treating DMF-containing wastewater involve activated carbon adsorption. The optimal adsorption temperature for activated carbon needs to be controlled between 25-40℃. Excessively high temperatures reduce the van der Waals forces between the activated carbon surface and DMF molecules, thus decreasing the adsorption capacity. In actual production applications, wastewater temperatures (across different batches) can fluctuate, and when the wastewater temperature exceeds 45℃, the adsorption effect on DMF is significantly reduced. Summary of the Invention

[0004] To address the problems existing in the background technology, the present invention provides a wastewater treatment process for continuous production of chloropropyne, which can effectively improve the adsorption rate and adsorption capacity of DMF when the wastewater temperature exceeds 45℃ (45-50℃).

[0005] To achieve the above objectives, the present invention provides the following technical solution: A wastewater treatment process for continuous production of chloropropyne involves adding 4-4.5g of oxidized flake graphite-modified activated carbon to 1L of wastewater at a wastewater temperature of 45-50℃ and an adsorption time of 45-55min. The preparation method of the oxide flake graphite-modified activated carbon is as follows: A1. Preparation of modified activated carbon: Pretreated activated carbon is obtained by pre-treating activated carbon, and then modified activated carbon is obtained by modifying the pretreated activated carbon with ammonia water. A2. Preparation of oxidized flake graphite: Flake graphite was oxidized by concentrated sulfuric acid and concentrated nitric acid to obtain oxidized flake graphite. A3. Mix the modified activated carbon obtained in A1 and the oxidized flake graphite obtained in A2 at a mass ratio of (3-3.5):1, and ball mill them to obtain oxidized flake graphite-modified activated carbon.

[0006] Furthermore, the specific operation of A1 is as follows: A11. Rinse the surface of the activated carbon with deionized water to remove dust, soluble salts and loose particles adsorbed by the activated carbon, and obtain the first activated carbon. A12. The first activated carbon is crushed by a crusher and then screened to obtain activated carbon particles; A13. Place the activated carbon granules in a drying oven and dry them to obtain pretreated activated carbon; A14. Take 3g of pretreated activated carbon and place it in 100mL of ammonia solution with a concentration of 6mol / L. Soak it at room temperature for 24h to obtain impregnated activated carbon. A15 involves rinsing the impregnated activated carbon three times with deionized water and then drying it in a drying oven to obtain modified activated carbon.

[0007] Furthermore, in A12, the particle size of the activated carbon particles is 20-30 mesh.

[0008] Furthermore, in A13, the activated carbon particles are dried with hot air at 100-110℃ in a drying oven for 40-50 minutes.

[0009] Furthermore, in A15, the drying temperature is 88-93℃ and the drying time is 10-12h.

[0010] Furthermore, the specific operation of A2 is as follows: A21. Soak flake graphite in a 2 mol / L hydrochloric acid solution and stir at 60-80℃ for 2-4 hours. Then wash with deionized water until neutral to obtain acid-washed graphite. A22. Take 20g of the acid-washed graphite obtained in A21 and put it into a 500mL beaker. Add 60mL of concentrated sulfuric acid and 20mL of concentrated nitric acid to the beaker. Add 60g of potassium permanganate to the beaker at 35-40℃. Stir the reaction in a constant temperature water bath at 35-40℃ for 2-4 hours to obtain graphite oxide. A23. The graphene oxide obtained in A22 was repeatedly centrifuged and washed with deionized water until the pH of the washing solution was 7. After standing and separating into layers, the upper suspension was collected and centrifuged to obtain the colloid. A24. The colloid obtained in A23 is purified by dialysis for 42-48 hours to remove ionic impurities, and then vacuum dried to obtain oxidized flake graphite.

[0011] Furthermore, in A21, the volume ratio of hydrochloric acid solution to flake graphite is (4-5) mL:1g.

[0012] Furthermore, in A22, the mass fraction of concentrated sulfuric acid is 95-98%, and the mass fraction of concentrated nitric acid is 62-65%.

[0013] Furthermore, in A24, the vacuum drying temperature is 65-75℃, and the vacuum drying time is 8-10h.

[0014] This application has the following beneficial effects: 1. Oxygen-containing groups (such as carboxyl-COOH and hydroxyl-OH) on the surface of oxidized flake graphite and amino groups (-NH2) on modified activated carbon are bonded by hydrogen bonds or covalent bonds to form a stable composite interface, which increases the density of polar adsorption sites and promotes the selective adsorption of carbonyl groups (C=O) in DMF molecules. The lone pair electrons of amino groups (-NH2) can also undergo charge transfer with oxygen-containing groups (such as carboxyl-COOH and hydroxyl-OH) on the surface of oxidized flake graphite, enhancing the surface polarity of the composite material and further improving the electrostatic adsorption capacity of DMF.

[0015] 2. The layered structure (interlayer spacing 1-5 nm) of flake graphite provides rigid support for modified activated carbon at temperatures of 45-50℃, inhibiting micropore collapse caused by high temperatures and maintaining the integrity of the pore structure. The high thermal conductivity (3000 W / m·K) of flake graphite can quickly conduct the heat generated during adsorption, avoiding excessive local temperature of modified activated carbon that could lead to amino decomposition or pore closure. Furthermore, the thermal environment of wastewater at 45-50℃ enhances the thermal motion of DMF molecules, enabling them to diffuse rapidly and orderly through the interlayer channels of flake graphite into the microporous region of modified activated carbon, thereby achieving a synergistic effect in improving the adsorption rate and adsorption capacity of DMF. Attached Figure Description

[0016] Figure 1 A comparative trend chart of DMF removal rate data of Examples 1-3 and Comparative Examples 1-3 in the experimental examples of this invention. Detailed Implementation

[0017] The present application will be further described in detail below with reference to the embodiments.

[0018] Unless otherwise specified, the raw materials used in the embodiments and comparative examples of this application are all commercially available.

[0019] Example 1: (1) Preparation of oxidized flake graphite-modified activated carbon, the preparation method is as follows: A1. Preparation of modified activated carbon: Pretreated activated carbon is obtained by pre-treating activated carbon, and then modified activated carbon is obtained by modifying the pretreated activated carbon with ammonia water.

[0020] The specific operation is as follows: A11. Rinse the activated carbon three times with deionized water, each time using a water volume five times the volume of the activated carbon. Simultaneously, use ultrasonic-assisted cleaning (40kHz frequency, 5 minutes) each time to remove adsorbed dust, soluble salts, and loose particles, obtaining the first activated carbon. A12. Crush the first activated carbon using a crusher and then sieve it to obtain activated carbon particles with a particle size of 20-30 mesh. A13. Dry the activated carbon particles in a forced-air drying oven at 105℃. The activated carbon particles are laid to a thickness of approximately 2cm, turned over every 15 minutes, for a total drying time of 45 minutes, obtaining pretreated activated carbon. A14. Place 3g of pretreated activated carbon in 100mL of ammonia solution with a concentration of 6mol / L, stir magnetically at 200rpm, and impregnate at room temperature for 24 hours to obtain impregnated activated carbon. A15 is made by rinsing the impregnated activated carbon three times with deionized water and then drying it in a drying oven. The thickness of the layer is about 1 cm. The drying temperature is 90℃ and the drying time is 11 hours to obtain the modified activated carbon.

[0021] A2. Preparation of oxidized flake graphite: Flake graphite is oxidized by treating it with concentrated sulfuric acid and concentrated nitric acid to obtain oxidized flake graphite.

[0022] The specific operation is as follows: A21. Soak flake graphite in a 2 mol / L hydrochloric acid solution, with a hydrochloric acid solution volume to flake graphite mass ratio of 4.5 mL: 1 g; stir at 300 rpm for 3 hours at 70℃, then wash with deionized water until neutral to obtain acid-washed graphite. A22. Take 20 g of the acid-washed graphite obtained in A21 and put it into a 500 mL beaker. Add 60 mL of 98% concentrated sulfuric acid and 20 mL of 65% concentrated nitric acid to the beaker. Slowly add 60 g of potassium permanganate to the beaker at 38℃ (add in batches, 10 g every 10 minutes). Stir and react in a constant temperature water bath at 38℃ (water bath accuracy ±1℃) for 3 hours to obtain graphite oxide. A23. Wash the graphite oxide obtained in A22 repeatedly with deionized water by centrifugation until the pH of the washing solution reaches 7. After standing and separating the layers, collect the upper suspension and centrifuge to obtain the colloid. The centrifugation parameters are: speed 5000 rpm, time 10 minutes / time, standing time 12 hours. The suspension is collected by siphoning the upper layer. A24. Purify the colloid obtained in A23 using a dialysis bag (molecular weight cutoff 8-14 kDa) for 45 hours, changing the water every 4 hours to remove ionic impurities. Then, dry under vacuum (10 Pa) at 70℃ for 9 hours to obtain graphite oxide flakes.

[0023] A3. Mix the modified activated carbon obtained in A1 and the oxidized flake graphite obtained in A2 at a mass ratio of 3.2:1, and then ball mill them. The ball mill speed is 400 rpm, the ball-to-material ratio is 10:1, the diameter of the zirconia balls used for ball milling is 5 mm, and the ball milling time is 4 h to obtain oxidized flake graphite-modified activated carbon.

[0024] The activated carbon used was coconut shell activated carbon, purchased from Hebei Jinbailin Activated Carbon Co., Ltd. The flake graphite, with a purity ≥99.9% and a particle size of 100 mesh, was purchased from Nanjing Xianfeng Nanomaterials Technology Co., Ltd.

[0025] (2) A wastewater treatment process for continuous production of chloropropyne, wherein 4.2g of oxidized flake graphite-modified activated carbon is added to 1L of wastewater, the wastewater temperature is about 48℃ (±1℃), and the adsorption time is 50min.

[0026] Example 2: The difference between this example and Example 1 is that: (1) Oxide flake graphite-modified activated carbon is prepared by the following method: A1. Preparation of modified activated carbon: Pretreated activated carbon is obtained by pre-treating activated carbon, and then modified activated carbon is obtained by modifying the pretreated activated carbon with ammonia water.

[0027] The specific operation is as follows: A11. Rinse the surface of activated carbon with deionized water to remove adsorbed dust, soluble salts, and loose particles, obtaining the first activated carbon. A12. Crush the first activated carbon using a crusher and then sieve it to obtain activated carbon particles with a particle size of 20-30 mesh. A13. Dry the activated carbon particles in a drying oven at 100℃ for 50 minutes to obtain pretreated activated carbon. A14. Place 3g of pretreated activated carbon in 100mL of ammonia solution with a concentration of 6mol / L and impregnate it at room temperature for 24 hours to obtain impregnated activated carbon. A15. Rinse the impregnated activated carbon three times with deionized water and then dry it in a drying oven at 88℃ for 12 hours to obtain modified activated carbon.

[0028] A2. Preparation of oxidized flake graphite: Flake graphite is oxidized by treating it with concentrated sulfuric acid and concentrated nitric acid to obtain oxidized flake graphite.

[0029] The specific procedures are as follows: A21. Soak flake graphite in a 2 mol / L hydrochloric acid solution, with a hydrochloric acid solution volume to flake graphite mass ratio of 4 mL:1 g; stir at 60℃ for 4 h, then wash with deionized water until neutral to obtain acid-washed graphite. A22. Take 20 g of the acid-washed graphite obtained in A21 and place it in a 500 mL beaker. Add 60 mL of 98% concentrated sulfuric acid and 20 mL of 65% concentrated nitric acid to the beaker. Slowly add 60 g of potassium permanganate to the beaker at 35℃ and stir the reaction in a 35℃ constant temperature water bath for 4 h to obtain graphite oxide. A23. Wash the graphite oxide obtained in A22 repeatedly with deionized water by centrifugation until the pH of the washing solution reaches 7. After standing and separating the layers, collect the upper suspension, centrifuge to separate the colloid. A24. The colloid obtained in A23 is purified by dialysis for 42 hours to remove ionic impurities, and then vacuum dried at 65°C for 10 hours to obtain oxidized flake graphite.

[0030] A3. Mix the modified activated carbon obtained in A1 and the oxidized flake graphite obtained in A2 at a mass ratio of 3:1, and ball mill them to obtain oxidized flake graphite-modified activated carbon.

[0031] (2) A wastewater treatment process for continuous production of chloropropyne, wherein 4.5g of oxidized flake graphite-modified activated carbon is added to 1L of wastewater, the wastewater temperature is about 46℃ (±1℃), and the adsorption time is 45min.

[0032] Example 3: The difference between this example and Example 1 is that: (1) Oxide flake graphite-modified activated carbon is prepared by the following method: A1. Preparation of modified activated carbon: Pretreated activated carbon is obtained by pre-treating activated carbon, and then modified activated carbon is obtained by modifying the pretreated activated carbon with ammonia water.

[0033] The specific operation is as follows: A11. Rinse the surface of activated carbon with deionized water to remove adsorbed dust, soluble salts, and loose particles, obtaining the first activated carbon. A12. Crush the first activated carbon using a crusher and then sieve it to obtain activated carbon particles with a particle size of 20-30 mesh. A13. Dry the activated carbon particles in a drying oven at 110℃ for 40 minutes to obtain pretreated activated carbon. A14. Place 3g of pretreated activated carbon in 100mL of ammonia solution with a concentration of 6mol / L and impregnate it at room temperature for 24 hours to obtain impregnated activated carbon. A15. Rinse the impregnated activated carbon three times with deionized water and then dry it in a drying oven at 93℃ for 10 hours to obtain modified activated carbon.

[0034] A2. Preparation of oxidized flake graphite: Flake graphite is oxidized by treating it with concentrated sulfuric acid and concentrated nitric acid to obtain oxidized flake graphite.

[0035] The specific procedures are as follows: A21. Soak flake graphite in a 2 mol / L hydrochloric acid solution, with a hydrochloric acid solution volume to flake graphite mass ratio of 5 mL:1 g; stir at 80℃ for 2 h, then wash with deionized water until neutral to obtain acid-washed graphite. A22. Take 20 g of the acid-washed graphite obtained in A21 and place it in a 500 mL beaker. Add 60 mL of 98% concentrated sulfuric acid and 20 mL of 65% concentrated nitric acid to the beaker. Slowly add 60 g of potassium permanganate to the beaker at 40℃ and stir the reaction in a 40℃ constant temperature water bath for 2 h to obtain graphite oxide. A23. Wash the graphite oxide obtained in A22 repeatedly with deionized water by centrifugation until the pH of the washing solution reaches 7. After standing and separating the layers, collect the upper suspension, centrifuge to separate the colloid. A24. The colloid obtained in A23 is purified by dialysis for 48 hours to remove ionic impurities, and then vacuum dried at 75°C for 8 hours to obtain oxidized flake graphite.

[0036] A3. Mix the modified activated carbon obtained in A1 and the oxidized flake graphite obtained in A2 at a mass ratio of 3.5:1, and ball mill them to obtain oxidized flake graphite-modified activated carbon.

[0037] (2) A wastewater treatment process for continuous production of chloropropyne, wherein 4g of oxidized flake graphite-modified activated carbon is added to 1L of wastewater, the wastewater temperature is about 49℃ (±1℃), and the adsorption time is 55min.

[0038] Comparative Example 1: The difference between this comparative example and Example 1 is that: oxidized flake graphite is removed, that is, oxidized flake graphite-modified activated carbon is replaced with modified activated carbon; and the wastewater temperature is about 28℃ (±1℃).

[0039] Specifically, a wastewater treatment process for continuous chloropropyne production involves adding 3.2g of modified activated carbon to 1L of wastewater at a wastewater temperature of approximately 28℃ (±1℃) and an adsorption time of 50min.

[0040] Comparative Example 2: The difference between this comparative example and Example 1 is that oxidized flake graphite is removed, that is, oxidized flake graphite-modified activated carbon is replaced with modified activated carbon.

[0041] Specifically, a wastewater treatment process for continuous chloropropyne production involves adding 3.2g of modified activated carbon to 1L of wastewater at a wastewater temperature of approximately 48℃ (±1℃) and an adsorption time of 50min.

[0042] Comparative Example 3: The difference between this comparative example and Example 1 is that the wastewater temperature is about 28°C (±1°C).

[0043] Specifically, a wastewater treatment process for continuous chloropropyne production involves adding 4.2g of oxidized flake graphite-modified activated carbon to 1L of wastewater at a wastewater temperature of approximately 28℃ (±1℃) and an adsorption time of 50min.

[0044] Experimental examples: Experimental subjects: Examples 1-3 and Comparative Examples 1-3.

[0045] Experimental Methods: The same batch of wastewater was used for the experiment, meaning the DMF content before adsorption was the same (the wastewater temperature in the corresponding examples / comparative examples was varied by heating / temperature control). The DMF content in the wastewater before and after adsorption was detected in each example and comparative example, and the DMF removal rate was calculated. The DMF content in the wastewater was detected using HPLC. The chromatographic column was a C18 column, the UV detector wavelength was 210 nm, and the mobile phase was acetonitrile-water with a volume ratio of acetonitrile to water of 5:95. DMF removal rate = (DMF content before adsorption - DMF content after adsorption) / DMF content before adsorption * 100%.

[0046] Experimental results: see Table 1.

[0047] Table 1. Experimental Data Results Analysis: Analysis of Examples 1-3, combined with data from Table 1 and... Figure 1 As can be seen, the oxidized flake graphite-modified activated carbon prepared by the present invention (Examples 1-3) has a DMF removal rate of up to 61.7% when the wastewater temperature is around 48℃ (±1℃).

[0048] Analyze Example 1 and Comparative Examples 1-3 and combine the data in Table 1 and Figure 1 Comparing Comparative Example 1 and Comparative Example 2, it can be seen that the DMF removal rate of Comparative Example 1, using modified activated carbon alone, is 57.9% when the wastewater temperature is around 28℃ (±1℃), which is significantly higher than the DMF removal rate of Comparative Example 2, using modified activated carbon alone, is 54.3% when the wastewater temperature is around 48℃ (±1℃). This indicates that when using modified activated carbon alone to adsorb DMF from wastewater, an increase in wastewater temperature from around 28℃ (±1℃) to around 48℃ (±1℃) will lead to a decrease in the DMF removal rate.

[0049] Comparing Comparative Examples 1 and 3, it can be seen that when the wastewater temperature is around 28℃ (±1℃), the DMF removal rate of Comparative Example 1 using modified activated carbon alone is 57.9%, which is significantly higher than the DMF removal rate of Comparative Example 3 using the oxidized flake graphite-modified activated carbon of this invention (55.6%). This indicates that when the wastewater temperature is around 28℃ (±1℃), converting the modified activated carbon into the oxidized flake graphite-modified activated carbon of this invention actually leads to a decrease in the DMF removal rate.

[0050] This is because the wastewater temperature is relatively low (around 28℃), and the thermal mobility of DMF molecules is relatively weak. The interlayer channels of oxidized flake graphite actually hinder the diffusion of DMF molecules, preventing them from rapidly diffusing into the microporous region of the modified activated carbon. As a result, the adsorption rate and adsorption capacity of the modified activated carbon for DMF decrease (within the same adsorption time), that is, the DMF removal rate decreases.

[0051] Comparing with Example 1, it can be seen that when the wastewater temperature is around 48℃ (±1℃), the DMF removal rate of Example 1 using the oxidized flake graphite-modified activated carbon of the present invention is 61.9%, which is significantly higher than the DMF removal rate of 54.3% using modified activated carbon in Comparative Example 2. This indicates that when the wastewater temperature is around 48℃ (±1℃), using the modified activated carbon prepared as the oxidized flake graphite-modified activated carbon of the present invention can significantly improve the DMF removal rate.

[0052] This is because the layered structure and high thermal conductivity of oxidized flake graphite, combined with the suitable temperature of the wastewater (around 48℃), allow DMF molecules to contact and be adsorbed more efficiently by the modified activated carbon. This synergistic effect not only increases the adsorption rate of DMF but also increases the adsorption capacity, thereby significantly improving the removal rate of DMF.

[0053] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0054] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A wastewater treatment process for continuous chloropropyne production, characterized in that, Add 4-4.5g of oxidized flake graphite-modified activated carbon to 1L of wastewater at a temperature of 45-50℃. The adsorption time for DMF is 45-55min. The preparation method of oxidized flake graphite-modified activated carbon is as follows: A1. Pretreated activated carbon is obtained by pre-treating activated carbon, and then modified activated carbon is obtained by impregnation with ammonia water. A2. Oxide flake graphite is obtained by oxidizing flake graphite with concentrated sulfuric acid and concentrated nitric acid. A3. Mix the modified activated carbon obtained in A1 and the oxidized flake graphite obtained in A2 at a mass ratio of (3-3.5):1, and ball mill them to obtain oxidized flake graphite-modified activated carbon.

2. The wastewater treatment process for continuous chloropropyne production according to claim 1, characterized in that, The specific steps for A1 are as follows: A11. Rinse the surface of the activated carbon with deionized water to remove dust, soluble salts and loose particles adsorbed by the activated carbon, and obtain the first activated carbon. A12. The first activated carbon is crushed by a crusher and then screened to obtain activated carbon particles; A13. Place the activated carbon granules in a drying oven and dry them to obtain pretreated activated carbon; A14. Take 3g of pretreated activated carbon and place it in 100mL of ammonia solution with a concentration of 6mol / L. Soak it at room temperature for 24h to obtain impregnated activated carbon. A15 involves rinsing the impregnated activated carbon three times with deionized water and then drying it in a drying oven to obtain modified activated carbon.

3. The wastewater treatment process for continuous chloropropyne production according to claim 2, characterized in that, In A12, the particle size of activated carbon particles is 20-30 mesh.

4. The wastewater treatment process for continuous chloropropyne production according to claim 2, characterized in that, In A13, the activated carbon particles are dried with hot air at 100-110℃ in a drying oven for 40-50 minutes.

5. The wastewater treatment process for continuous chloropropyne production according to claim 2, characterized in that, In A15, the drying temperature is 88-93℃ and the drying time is 10-12h.

6. The wastewater treatment process for continuous chloropropyne production according to claim 1, characterized in that, The specific steps for A2 are as follows: A21. Soak flake graphite in a 2 mol / L hydrochloric acid solution and stir at 60-80℃ for 2-4 hours. Then wash with deionized water until neutral to obtain acid-washed graphite. A22. Take 20g of the acid-washed graphite obtained in A21 and put it into a 500mL beaker. Add 60mL of concentrated sulfuric acid and 20mL of concentrated nitric acid to the beaker. Add 60g of potassium permanganate to the beaker at 35-40℃. Stir the reaction in a constant temperature water bath at 35-40℃ for 2-4 hours to obtain graphite oxide. A23. The graphene oxide obtained in A22 was repeatedly centrifuged and washed with deionized water until the pH of the washing solution was 7. After standing and separating into layers, the upper suspension was collected and centrifuged to obtain the colloid. A24. The colloid obtained in A23 is purified by dialysis for 42-48 hours to remove ionic impurities, and then vacuum dried to obtain oxidized flake graphite.

7. The wastewater treatment process for continuous chloropropyne production according to claim 6, characterized in that, In A21, the volume ratio of hydrochloric acid solution to flake graphite is (4-5) mL:1g.

8. The wastewater treatment process for continuous chloropropyne production according to claim 6, characterized in that, In A22, the mass fraction of concentrated sulfuric acid is 95-98%, and the mass fraction of concentrated nitric acid is 62-65%.

9. The wastewater treatment process for continuous chloropropyne production according to claim 6, characterized in that, In A24, the vacuum drying temperature is 65-75℃, and the vacuum drying time is 8-10h.

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