Wastewater treatment process for continuous production of chloropropyne

Abstract

The invention provides a wastewater treatment process for continuous production of chloropropyne, and belongs to the technical field of wastewater treatment.The process comprises the steps that 4-4.5 g of oxidized flake graphite-modified activated carbon is added 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 flake graphite-modified activated carbon comprises the following steps: A1, preparing the modified activated carbon; activated carbon is pretreated to obtain pretreated activated carbon, and then the pretreated activated carbon is modified by ammonia water to obtain modified activated carbon; a2, preparing oxidized flake graphite; oxidizing crystalline flake graphite with concentrated sulfuric acid and concentrated nitric acid to obtain oxidized crystalline flake graphite; and A3, mixing the modified activated carbon and crystalline flake graphite according to a mass ratio of (3-3.5): 1, and carrying out ball milling to obtain the crystalline flake graphite-modified activated carbon. The method can effectively increase the adsorption rate and adsorption capacity of DMF when the temperature of the wastewater exceeds 45 DEG C (45-50 DEG C).

Description

Technical Field

[0001] The present invention belongs to the technical field of wastewater treatment, and particularly relates to a wastewater treatment process for continuous production of propargyl chloride. Background Art

[0002] During the production of propargyl chloride, raw material thionyl chloride and catalyst DFM can be pumped into a mixer for mixing, and then fully mixed and reacted with the pumped raw material propargyl alcohol in a reactor to raise the temperature. Then, the reaction and aging are carried out under suitable temperature and pressure conditions. Finally, the continuous reaction solution is cooled by a condensing device, and the obtained crude product is stripped to remove light components to obtain propargyl chloride product. The propargyl chloride product is washed with water and rectified to obtain a pure propargyl chloride product. That is, thionyl chloride in propargyl chloride is removed by water washing and DMF is removed. After water washing, wastewater containing DMF is obtained. The mass fraction of DMF in the wastewater containing DMF is 0.5% - 5%. Since DMF is toxic and pollutes the environment, the wastewater containing DMF cannot be directly discharged and needs to be treated.

[0003] The existing treatment method for wastewater containing DMF is to use activated carbon adsorption. The optimal adsorption temperature of activated carbon needs to be controlled at 25 - 40 °C. When the temperature rises too high, the van der Waals force between the surface of activated carbon and DMF molecules will be reduced, resulting in a decrease in adsorption capacity. In actual production applications, the temperature of wastewater (in different batches) will fluctuate. When the wastewater temperature is greater than 45 °C, the adsorption effect on DMF will be significantly reduced. Summary of the Invention

[0004] To solve the problems in the background art, the present invention provides a wastewater treatment process for continuous production of propargyl chloride, which can effectively improve the adsorption rate and adsorption capacity of DMF when the wastewater temperature exceeds 45 °C (45 - 50 °C).

[0005] To achieve the above object, the present invention provides the following technical solutions: A wastewater treatment process for continuous production of propargyl chloride, adding 4 - 4.5 g of oxidized flake graphite - modified activated carbon into 1 L of wastewater, with the wastewater temperature being 45 - 50 °C and the adsorption time being 45 - 55 min; The preparation method of the oxidized flake graphite - modified activated carbon is as follows: A1. Prepare modified activated carbon; the activated carbon is pretreated to obtain pretreated activated carbon, and then the pretreated activated carbon is subjected to ammonia modification treatment to obtain modified activated carbon; A2. Prepare oxidized flake graphite; the flake graphite is 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 according to a mass ratio of (3 - 3.5):1, and ball - mill to obtain oxidized flake graphite - modified activated carbon.

[0006] Further, the specific operations of A1 are as follows: A11. Rinse the surface of the activated carbon with deionized water to remove the dust, soluble salts, and loose particles adsorbed by the activated carbon, obtaining the first activated carbon; A12. Crush and screen the first activated carbon using a crusher to obtain activated carbon particles; A13. Place the activated carbon particles in a drying oven for drying to obtain pretreated activated carbon; A14. Take 3 g of the pretreated activated carbon and place it in an ammonia water solution with a volume of 100 mL and a concentration of 6 mol / L, and impregnate it at room temperature for 24 h to obtain impregnated activated carbon; A15. After rinsing the impregnated activated carbon three times with deionized water, place it in a drying oven for drying to obtain modified activated carbon.

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

[0008] Further, in A13, the activated carbon particles are dried by hot air in a drying oven at 100 - 110 °C, and the drying time is 40 - 50 min.

[0009] Further, in A15, the drying temperature is 88 - 93 °C, and the drying time is 10 - 12 h.

[0010] Further, the specific operations of A2 are as follows: A21. Immerse the flake graphite in a hydrochloric acid solution with a concentration of 2 mol / L, stir it at 60 - 80 °C for 2 - 4 h, and then wash it with deionized water until it is neutral to obtain pickled graphite; A22. Take 20 g of the pickled graphite obtained in A21 and put it into a 500 mL beaker. Add 60 mL of concentrated sulfuric acid and 20 mL of concentrated nitric acid to the beaker. Add 60 g of potassium permanganate to the beaker at 35 - 40 °C, and stir and react in a 35 - 40 °C constant temperature water bath for 2 - 4 h to obtain oxidized graphite; A23. Repeatedly centrifuge and wash the oxidized graphite obtained in A22 with deionized water until the pH of the washing solution is 7. After standing for stratification, collect the upper suspension and perform centrifugal separation to obtain a colloid; A24. Purify the colloid obtained in A23 with a dialysis bag for 42 - 48 h to remove ionic impurities, and then perform vacuum drying to obtain oxidized flake graphite.

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

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

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

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

[0015] 2. The layered structure of oxidized flake graphite (layer spacing 1 - 5 nm) provides rigid support for the modified activated carbon at a temperature of 45 - 50 °C, inhibiting the micropore collapse caused by high temperature and maintaining the integrity of the pore structure; the high thermal conductivity (3000 W / m·K) of oxidized flake graphite can quickly conduct the heat generated during the adsorption process, avoiding the decomposition of amino groups or pore closure due to excessive local temperature of the modified activated carbon; moreover, the thermal environment with the wastewater temperature of 45 - 50 °C enhances the thermal motion of DMF molecules, enabling them to diffuse rapidly and orderly into the micropore region of the modified activated carbon through the interlayer channels of oxidized flake graphite, thereby achieving the effect of synergistically improving the adsorption rate and adsorption capacity for DMF. Description of the Drawings

[0016] Figure 1 、Trend chart of the comparison of DMF removal rate data of Examples 1 - 3 and Comparative Examples 1 - 3 in the test examples of the present invention. Detailed Embodiments

[0017] The following further details the present application with reference to the embodiments.

[0018] The raw materials of the embodiments and comparative examples of the present application are all ordinary commercially available products unless otherwise specified.

[0019] Example 1: (1) Preparation of oxidized flake graphite - modified activated carbon, and its preparation method is as follows: A1. Preparation of modified activated carbon; the activated carbon is pretreated to obtain pretreated activated carbon, and then the pretreated activated carbon is modified with ammonia water to obtain modified activated carbon.

[0020] The specific operations are as follows: A11. Rinse the activated carbon with deionized water three times, with the amount of water for each rinse being 5 times the volume of the activated carbon. Meanwhile, use ultrasonic-assisted cleaning each time (ultrasonic frequency: 40 kHz, time: 5 minutes) to remove the dust, soluble salts, and loose particles adsorbed by the activated carbon, obtaining the first activated carbon. A12. Crush and screen the first activated carbon using a crusher to obtain activated carbon particles with a particle size of 20 - 30 mesh. A13. Conduct hot air drying on the activated carbon particles in a forced-air drying oven at 105°C. The thickness of the laid-activated carbon particles is about 2 cm, and they are turned over every 15 minutes. The total drying time is 45 minutes, obtaining the pretreated activated carbon. A14. Take 3 g of the pretreated activated carbon and place it in an ammonia water solution with a volume of 100 mL and a concentration of 6 mol / L. Stir magnetically at a rotation speed of 200 rpm and impregnate at room temperature for 24 hours to obtain the impregnated activated carbon. A15. After rinsing the impregnated activated carbon three times with deionized water, place it in a drying oven for drying. When drying, the laid thickness is about 1 cm in a thin layer, the drying temperature is 90°C, and the drying time is 11 hours, thus obtaining the modified activated carbon.

[0021] A2. Prepare oxidized flake graphite; the flake graphite is treated by oxidation with concentrated sulfuric acid and concentrated nitric acid to obtain oxidized flake graphite.

[0022] The specific operations are as follows: A21. Immerse the flake graphite in a hydrochloric acid solution with a concentration of 2 mol / L. The volume ratio of the hydrochloric acid solution to the mass of the flake graphite is 4.5 mL:1 g; stir at 300 rpm at 70°C for 3 hours, and then wash with deionized water until neutral to obtain the pickled graphite. A22. Take 20 g of the pickled graphite obtained in A21 and put it into a 500 mL beaker. Add 60 mL of concentrated sulfuric acid with a mass fraction of 98% and 20 mL of concentrated nitric acid with a mass fraction of 65% to the beaker. Slowly add 60 g of potassium permanganate to the beaker at 38°C (add in batches, 10 g each time for 10 minutes), and stir and react in a 38°C constant-temperature water bath (water bath accuracy ±1°C) for 3 hours to obtain oxidized graphite. A23. Repeatedly centrifuge and wash the oxidized graphite obtained in A22 with deionized water until the pH of the washing solution is 7. After standing and separating layers, collect the upper suspension and perform centrifugal separation to obtain a colloid; among them, the centrifugation parameters are a rotation speed of 5000 rpm and a time of 10 minutes per time, the standing time is 12 hours, and the suspension collection method is to take the upper layer liquid by siphon. A24. Purify the colloid obtained in A23 with a dialysis bag (specification: cut-off molecular weight 8 - 14 kDa) for 45 hours, with the water change frequency being once every 4 hours to remove ionic impurities, and then perform vacuum drying (10 Pa). The vacuum drying temperature is 70°C, and the vacuum drying time is 9 hours, thus obtaining the oxidized flake graphite.

[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 carry out ball milling. The rotation speed of the ball mill is 400 rpm, the ball-to-material ratio is 10:1, the diameter of the zirconia balls used as the ball milling medium is 5 mm, and the ball milling time is 4 h, thus obtaining oxidized flake graphite-modified activated carbon.

[0024] Among them, the activated carbon is coconut shell activated carbon, purchased from Hebei Jinbailin Activated Carbon Co., Ltd. The purity of the flake graphite is ≥99.9%, the particle size is 100 mesh, and it is purchased from Nanjing Xianfeng Nano Materials Technology Co., Ltd.

[0025] (2) A wastewater treatment process for the continuous production of propargyl chloride. Add 4.2 g of oxidized flake graphite-modified activated carbon to 1 L of wastewater. The temperature of the wastewater is about 48 °C (±1 °C), and the adsorption time is 50 min.

[0026] Example 2: The difference between this example and Example 1 is: (1) Preparation of oxidized flake graphite-modified activated carbon, and its preparation method is as follows: A1. Preparation of modified activated carbon; After the activated carbon is pretreated to obtain pretreated activated carbon, and then the pretreated activated carbon is modified with ammonia water to obtain modified activated carbon.

[0027] The specific operations are as follows: A11. Rinse the surface of the activated carbon with deionized water to remove the dust, soluble salts and loose particles adsorbed by the activated carbon, obtaining the first activated carbon. A12. Crush and screen the first activated carbon with a crusher to obtain activated carbon particles with a particle size of 20 - 30 mesh. A13. The activated carbon particles are dried by hot air at 100 °C in a drying oven for 50 min to obtain pretreated activated carbon. A14. Take 3 g of pretreated activated carbon and place it in an ammonia water solution with a volume of 100 mL and a concentration of 6 mol / L, and soak it at room temperature for 24 h to obtain impregnated activated carbon. A15. After the impregnated activated carbon is rinsed three times with deionized water, it is placed in a drying oven for drying, the drying temperature is 88 °C, and the drying time is 12 h, thus obtaining modified activated carbon.

[0028] A2. Preparation of oxidized flake graphite; The flake graphite is oxidized with concentrated sulfuric acid and concentrated nitric acid to obtain oxidized flake graphite.

[0029] The specific operations are as follows: A21. Immerse the flake graphite in a hydrochloric acid solution with a concentration of 2 mol / L, and the volume ratio of the hydrochloric acid solution to the mass of the flake graphite is 4 mL:1 g; stir at 60 °C for 4 h, and 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 concentrated sulfuric acid with a mass fraction of 98% and 20 mL of concentrated nitric acid with a mass fraction of 65% to the beaker. Slowly add 60 g of potassium permanganate to the beaker at 35 °C, and stir and react in a 35 °C constant temperature water bath for 4 h to obtain oxidized graphite. A23. Centrifuge and wash the oxidized graphite obtained in A22 with deionized water repeatedly until the pH of the washing solution is 7. After standing and separating into layers, collect the upper suspension and centrifuge to obtain a colloid. A24. Purify the colloid obtained in A23 with a dialysis bag for 42 h to remove ionic impurities, and then dry it in vacuo. The vacuum drying temperature is 65 °C and the vacuum drying time is 10 h to obtain oxidized flake graphite.

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

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

[0032] Example 3: The difference between this example and Example 1 is: (1) Prepare oxidized flake graphite-modified activated carbon, and its preparation method is as follows: A1. Prepare modified activated carbon; after pretreating the activated carbon to obtain pretreated activated carbon, and then subject the pretreated activated carbon to ammonia modification treatment to obtain modified activated carbon.

[0033] The specific operations are as follows: A11. Rinse the surface of the activated carbon with deionized water to remove the dust, soluble salts and loose particles adsorbed by the activated carbon to obtain the first activated carbon. A12. Crush and screen the first activated carbon with a crusher to obtain activated carbon particles, and the particle size of the activated carbon particles is 20 - 30 mesh. A13. Hot air dry the activated carbon particles in a drying oven at 110 °C for 40 min to obtain pretreated activated carbon. A14. Take 3 g of the pretreated activated carbon and place it in an ammonia water solution with a volume of 100 mL and a concentration of 6 mol / L, and immerse it at room temperature for 24 h to obtain impregnated activated carbon. A15. After rinsing the impregnated activated carbon three times with deionized water, place it in a drying oven to dry, the drying temperature is 93 °C, and the drying time is 10 h to obtain modified activated carbon.

[0034] A2. Prepare oxidized flake graphite; oxidize the flake graphite with concentrated sulfuric acid and concentrated nitric acid to obtain oxidized flake graphite.

[0035] The specific operations are as follows: A21. Immerse flake graphite in a hydrochloric acid solution with a concentration of 2 mol / L, and the volume ratio of the hydrochloric acid solution to the mass of the flake graphite is 5 mL:1 g; stir at 80 °C for 2 h, and 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 concentrated sulfuric acid with a mass fraction of 98% and 20 mL of concentrated nitric acid with a mass fraction of 65% to the beaker. Slowly add 60 g of potassium permanganate to the beaker at 40 °C, and stir and react in a 40 °C constant temperature water bath for 2 h to obtain oxidized graphite. A23. Repeatedly centrifuge and wash the oxidized graphite obtained in A22 with deionized water until the pH of the washing solution is 7. After standing and separating layers, collect the upper suspension and centrifuge to obtain a colloid. A24. Purify the colloid obtained in A23 with a dialysis bag for 48 h to remove ionic impurities, and then perform vacuum drying. The vacuum drying temperature is 75 °C, and the vacuum drying time is 8 h to obtain oxidized flake graphite.

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

[0037] (2) A wastewater treatment process for continuous production of propargyl chloride. Add 4 g of oxidized flake graphite-modified activated carbon to 1 L of wastewater. The wastewater temperature is about 49 °C (±1 °C), and the adsorption time is 55 min.

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

[0039] Specifically, a wastewater treatment process for continuous production of propargyl chloride. Add 3.2 g of modified activated carbon to 1 L of wastewater. The wastewater temperature is about 28 °C (±1 °C), and the adsorption time is 50 min.

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

[0041] Specifically, a wastewater treatment process for continuous production of propargyl chloride. Add 3.2 g of modified activated carbon to 1 L of wastewater. The wastewater temperature is about 48 °C (±1 °C), and the adsorption time is 50 min.

[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, for a wastewater treatment process for continuous production of propargyl chloride, 4.2 g of oxidized flake graphite-modified activated carbon is added to 1 L of wastewater. The wastewater temperature is about 28 °C (±1 °C), and the adsorption time is 50 min.

[0044] Test examples: Test objects: Examples 1 - 3 and Comparative Examples 1 - 3.

[0045] Test method: The same batch of wastewater is used for the test, that is, the DMF content before adsorption is the same (the wastewater temperature in the corresponding examples / comparative examples is made different by heating / temperature control). The DMF content of the wastewater before and after adsorption in each example and comparative example is detected and the DMF removal rate is calculated; Detection method for DMF content in wastewater: HPLC is used to detect the DMF content in the wastewater. The chromatographic column is a C18 column, the detection wavelength of the ultraviolet detector is 210 nm, the mobile phase is acetonitrile-water, and the volume ratio of acetonitrile to water is 5:95; DMF removal rate = (DMF content before adsorption - DMF content after adsorption) / DMF content before adsorption * 100%.

[0046] Test results: See Table 1.

[0047] Table 1. Data of test examples Result analysis: Analyze Examples 1 - 3 and combine with the data in Table 1 and Figure 1 , it can be seen that the DMF removal rate of the oxidized flake graphite-modified activated carbon prepared by the present invention (Examples 1 - 3) is as high as over 61.7% when the wastewater temperature is about 48 °C (±1 °C).

[0048] Analyze Example 1 and Comparative Examples 1 - 3 and combine with the data in Table 1 and Figure 1 , by comparing Comparative Example 1 and Comparative Example 2, it can be known that the DMF removal rate of Comparative Example 1 using modified activated carbon alone at a wastewater temperature of about 28 °C (±1 °C) is 57.9%, which is significantly greater than the DMF removal rate of Comparative Example 2 using modified activated carbon alone at a wastewater temperature of about 48 °C (±1 °C), which is 54.3%. It shows that when using modified activated carbon alone for adsorption treatment of DMF in wastewater, when the wastewater temperature is increased from about 28 °C (±1 °C) to about 48 °C (±1 °C), the DMF removal rate will decrease.

[0049] Comparing Comparative Example 1 and Comparative Example 3, it can be seen that when the wastewater temperature is about 28 °C (±1 °C), the DMF removal rate of Comparative Example 1 using modified activated carbon alone is 57.9%, which is significantly greater than the DMF removal rate of 55.6% of Comparative Example 3 using the oxidized flake graphite-modified activated carbon of the present invention. It shows that when the wastewater temperature is about 28 °C (±1 °C), making the modified activated carbon into the oxidized flake graphite-modified activated carbon of the present invention will instead cause a decrease in the DMF removal rate.

[0050] This is because the wastewater temperature is relatively low (about 28 °C), the thermal motion ability of DMF molecules is weak, and the interlayer channels of oxidized flake graphite will instead hinder the diffusion movement of DMF molecules, preventing them from quickly diffusing to the microporous region of the modified activated carbon, resulting in a decrease in the adsorption rate and adsorption capacity of the modified activated carbon for DMF (within the same adsorption time), that is, a decrease in the DMF removal rate.

[0051] Combined with Example 1 for comparison, it can be seen that when the wastewater temperature is about 48 °C (±1 °C), 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 greater than the DMF removal rate of 54.3% of Comparative Example 2 using modified activated carbon. It shows that when the wastewater temperature is about 48 °C (±1 °C), making the modified activated carbon into the oxidized flake graphite-modified activated carbon of the present invention for use can significantly improve the DMF removal rate.

[0052] This is because the combined action of the layered structure, high thermal conductivity of oxidized flake graphite and the appropriate wastewater temperature (about 48 °C) enables DMF molecules to contact and be adsorbed by the modified activated carbon more efficiently. This synergistic effect not only improves the adsorption rate of DMF but also increases the adsorption capacity, thus significantly enhancing the DMF removal rate.

[0053] In addition, it should be noted that each of the specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0054] Furthermore, any combination can be made between various different embodiments of the present invention as long as it does not violate the idea of the present invention, and it should also be regarded as the content disclosed by the present invention.

Claims

1. A wastewater treatment process for the continuous production of propargyl chloride, characterized in that, Add 4 - 4.5 g of oxidized flake graphite - modified activated carbon to 1 L of wastewater. The temperature of the wastewater is 45 - 50 °C, and the adsorption time is 45 - 55 min. The preparation method of the oxidized flake graphite - modified activated carbon is as follows: A1. Pretreat the activated carbon to obtain pretreated activated carbon, and then subject the pretreated activated carbon to ammonia modification treatment to obtain modified activated carbon; A2. Oxidize the flake graphite with 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 according to the mass ratio of (3 - 3.5):1, and ball - mill to obtain oxidized flake graphite - modified activated carbon.

2. The wastewater treatment process for continuously producing propargyl chloride according to claim 1, characterized in that, The specific operation of A1 is as follows: A11. Rinse the surface of the activated carbon with deionized water to remove the dust, soluble salts, and loose particles adsorbed by the activated carbon, and obtain the first activated carbon; A12. Crush and screen the first activated carbon with a crusher to obtain activated carbon particles; A13. Place the activated carbon particles in a drying oven for drying to obtain pretreated activated carbon; A14. Take 3 g of pretreated activated carbon and place it in an ammonia water solution with a volume of 100 mL and a concentration of 6 mol / L, and immerse it at room temperature for 24 h to obtain impregnated activated carbon; A15. After rinsing the impregnated activated carbon three times with deionized water, place it in a drying oven for drying to obtain modified activated carbon.

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

4. The wastewater treatment process for continuously producing propargyl chloride according to claim 2, characterized in that, In A13, the activated carbon particles are dried by hot air at 100 - 110 °C in the drying oven, and the drying time is 40 - 50 min.

5. The wastewater treatment process for continuously producing propargyl chloride according to claim 2, characterized in that, In A15, the drying temperature is 88 - 93 °C, and the drying time is 10 - 12 h.

6. The wastewater treatment process for continuously producing propargyl chloride according to claim 1, wherein The specific operation of A2 is as follows: A21. Soak the flake graphite with a 2 - mol / L hydrochloric acid solution, stir at 60 - 80 °C for 2 - 4 h, and then wash it with deionized water until it is neutral to obtain pickled graphite; A22. Take 20 g of the pickled graphite obtained in A21 and put it into a 500 - mL beaker. Add 60 mL of concentrated sulfuric acid and 20 mL of concentrated nitric acid to the beaker. Add 60 g of potassium permanganate to the beaker at 35 - 40 °C, and stir and react in a 35 - 40 °C constant - temperature water bath for 2 - 4 h to obtain oxidized graphite; A23. Repeatedly centrifuge and wash the oxidized graphite obtained in A22 with deionized water until the pH of the washing solution is 7. After standing and separating into layers, collect the upper - layer suspension and centrifuge to obtain a colloid; A24. Purify the colloid obtained in A23 with a dialysis bag for 42 - 48 h to remove ionic impurities, and then perform vacuum drying to obtain oxidized flake graphite.

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

8. The wastewater treatment process for continuously producing propargyl chloride 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 continuously producing propargyl chloride according to claim 6, characterized in that, In A24, the vacuum drying temperature is 65 - 75 °C, and the vacuum drying time is 8 - 10 h.

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