Preparation method and application of porous carbon with mesoporous aperture

Abstract

The invention relates to a preparation method and application of porous carbon with mesoporous aperture, and belongs to the technical field of activated carbon. The invention provides a preparation method of porous carbon with mesoporous aperture, which comprises the following steps: ball-milling rice husk, pickling to remove impurities, drying, mixing with a phosphoric acid solution, drying, pre-carbonizing at low temperature, activating at medium temperature, treating at high temperature, removing silicon by alkali washing, and treating by microwave-steam to obtain the porous carbon with mesoporous aperture. The method can be applied to organic dye wastewater treatment and pharmaceutical wastewater treatment. According to the invention, rice husk is used as a natural template to generate mesopores, no extra template agent is needed, low-temperature pre-carbonization, medium-temperature activation and high-temperature treatment are carried out, CO2 is used for assisting pore expansion at the same time, and finally microwave irradiation is combined with water vapor treatment, so that pore defects generated in the high-temperature carbonization process are repaired, and the stability of oxygen-containing functional groups on the surface is enhanced; porous carbon with mesoporous aperture is obtained, and pollutants with the aperture larger than 2 nm can be effectively adsorbed.

Description

Technical Field

[0001] The invention belongs to the technical field of activated carbon and relates to a preparation method of porous carbon with mesopore diameter and application thereof. Background Art

[0002] Activated carbon is a porous carbon material that has been treated by a special process. Due to its developed pore structure and huge specific surface area, it is used as an efficient adsorbent in the field of environmental protection. However, traditional activated carbon is mostly characterized by a pore structure dominated by micropores (<2nm), which has obvious limitations in practical applications. For example, organic dye wastewater or pharmaceutical wastewater may contain a variety of complexes or macromolecules with molecular sizes exceeding 2nm. The microporous structure will produce a steric hindrance effect, thereby reducing the adsorption capacity; secondly, the narrow pore structure causes the pollutant molecules to undergo a long diffusion process before reaching the internal adsorption sites; thirdly, the micropores are prone to structural collapse during the regeneration process, seriously affecting the service life of the material. Summary of the Invention

[0003] The purpose of the present invention is to provide a preparation method and application of porous carbon with mesopore size. The present invention uses rice husk as a natural template to generate mesopores without the need for additional template agents. It undergoes low-temperature pre-carbonization, medium-temperature activation, and high-temperature treatment while using CO2-assisted pore expansion. Finally, microwave irradiation combined with water vapor treatment is used to repair the pore defects generated during the high-temperature carbonization process and enhance the stability of the surface oxygen-containing functional groups, thereby obtaining a porous carbon with a mesopore size that can effectively adsorb pollutants with a pore size greater than 2 nm.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A method for preparing porous carbon having mesopores, the method comprising the following steps:

[0006] Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material;

[0007] Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material;

[0008] Step 3: pre-carbonizing the activated raw material at a relatively low temperature, activating it at a medium temperature, and treating it at a relatively high temperature to obtain a carbonized product;

[0009] Step 4: The carbonized product is subjected to alkali washing to remove silicon, and microwave-steam treatment to obtain porous carbon with mesopores.

[0010] Furthermore, the ball milling in step 1 refers to ball milling at a speed of 400-500 rpm for 2.5-3.5 hours; the acid washing refers to soaking in 0.8-1.2 mol / L hydrochloric acid solution for 2-3 hours and washing with deionized water until neutral; the drying temperature is 80°C.

[0011] Furthermore, in step 2, the mass ratio of the raw materials to the phosphoric acid solution is 1:1.4-1.6; the content of phosphoric acid in the phosphoric acid solution is 31-35wt%; the mixing refers to setting the ultrasonic frequency to 30-50kHz, the ultrasonic power to 300-400W, and the ultrasonication for 0.8-1.2h; and the drying refers to drying at 120°C to constant weight.

[0012] Furthermore, the lower temperature pre-carbonization in step 3 refers to heating to 298-302° C. at a rate of 1.5-2.5° C. / min under a nitrogen atmosphere and keeping the temperature for 1-2 hours.

[0013] Furthermore, the medium-temperature activation in step 3 refers to heating to 590-610°C at a rate of 4.5-5.5°C / min and keeping the temperature for 2-3 hours.

[0014] Furthermore, the higher temperature treatment in step 3 refers to raising the temperature to 780-820°C at a rate of 2.5-3.5°C, keeping the temperature for 0.5-0.7h while introducing CO2 at a flow rate of 45-55mL / min.

[0015] Furthermore, the alkaline washing and silicon removal in step 4 refers to soaking in 1.5-2.5 mol / L sodium hydroxide solution for 5-7 hours and washing with deionized water until neutral.

[0016] Furthermore, the microwave-steam treatment in step 4 refers to microwave irradiation at 550-650W for 2.5-3.5 minutes, while introducing water vapor at a flow rate of 8-12 mL / min.

[0017] Furthermore, the porous carbon is applied to the treatment of organic dye wastewater and pharmaceutical wastewater.

[0018] Beneficial effects of the present invention:

[0019] (1) The present invention uses rice husk as a natural template to generate mesopores without the need for additional template agents. The method uses low-temperature pre-carbonization, medium-temperature activation, and high-temperature treatment while using CO2 to assist in pore expansion. Finally, microwave irradiation combined with water vapor treatment is used to repair the pore defects generated during the high-temperature carbonization process and enhance the stability of the surface oxygen-containing functional groups, thereby obtaining a porous carbon with a mesopore diameter that can effectively adsorb pollutants with a pore diameter greater than 2 nm.

[0020] (2) During the temperature treatment of the present invention, the hemicellulose and cellulose in the rice husk are pyrolyzed, releasing CO2, H2O and small molecular organic matter to form an initial carbon skeleton. At this time, phosphoric acid penetrates into the interior of the biomass, and dehydration promotes condensation between biomass molecules to form micropores and mesopore prototypes; then, during medium-temperature activation, phosphoric acid decomposes into polyphosphoric acid, further promoting the carbonization reaction, and forming mesopores through pore formation and pore expansion; finally, after a higher temperature treatment, CO2 assists in pore expansion, dredges the pores, and improves pore connectivity and structural stability. DETAILED DESCRIPTION

[0021] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.

[0022] All the examples and comparative examples of the present invention were purchased directly from the market;

[0023] Example 1

[0024] A method for preparing porous carbon having mesopores, the method comprising the following steps:

[0025] Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material;

[0026] Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material;

[0027] Step 3: pre-carbonizing the activated raw material at a relatively low temperature, activating it at a medium temperature, and treating it at a relatively high temperature to obtain a carbonized product;

[0028] Step 4: The carbonized product is subjected to alkali washing to remove silicon, and microwave-steam treatment to obtain porous carbon with mesopores.

[0029] The ball milling in step 1 refers to ball milling at a speed of 400 rpm for 2.5 hours; the acid washing refers to soaking in 0.8 mol / L hydrochloric acid solution for 2 hours and washing with deionized water until neutral; the drying temperature is 80°C.

[0030] In step 2, the mass ratio of the raw materials to the phosphoric acid solution is 1:1.4; the content of phosphoric acid in the phosphoric acid solution is 31 wt%; the mixing refers to setting the ultrasonic frequency to 30 kHz, the ultrasonic power to 300 W, and the ultrasonication for 0.8 h; the drying refers to drying at 120° C. to constant weight.

[0031] The lower temperature pre-carbonization in step 3 refers to heating to 298°C at a rate of 1.5°C / min under a nitrogen atmosphere and keeping the temperature for 1 hour.

[0032] The medium-temperature activation in step 3 refers to heating to 590°C at a rate of 4.5°C / min and keeping the temperature for 2 hours.

[0033] The higher temperature treatment in step 3 refers to raising the temperature to 780°C at a rate of 2.5°C, keeping the temperature for 0.5h, and introducing CO2 at a flow rate of 45mL / min.

[0034] The alkaline washing and silicon removal in step 4 refers to soaking in 1.5 mol / L sodium hydroxide solution for 5 hours and washing with deionized water until neutral.

[0035] The microwave-steam treatment in step 4 refers to 550W microwave irradiation for 2.5 minutes, while water vapor is introduced at a flow rate of 8 mL / min.

[0036] The porous carbon is applied to the treatment of organic dye wastewater and pharmaceutical wastewater.

[0037] Example 2

[0038] A method for preparing porous carbon having mesopores, the method comprising the following steps:

[0039] Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material;

[0040] Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material;

[0041] Step 3: pre-carbonizing the activated raw material at a relatively low temperature, activating it at a medium temperature, and treating it at a relatively high temperature to obtain a carbonized product;

[0042] Step 4: The carbonized product is subjected to alkali washing to remove silicon, and microwave-steam treatment to obtain porous carbon with mesopores.

[0043] The ball milling in step 1 refers to ball milling at a speed of 430 rpm for 2.8 hours; the acid washing refers to soaking in 0.9 mol / L hydrochloric acid solution for 2.3 hours and washing with deionized water until neutral; the drying temperature is 80°C.

[0044] In step 2, the mass ratio of the raw materials to the phosphoric acid solution is 1:1.46; the content of phosphoric acid in the phosphoric acid solution is 32 wt%; the mixing refers to setting the ultrasonic frequency to 35 kHz, the ultrasonic power to 320 W, and the ultrasonication for 0.9 h; the drying refers to drying at 120° C. to constant weight.

[0045] The lower temperature pre-carbonization in step 3 refers to heating to 299° C. at a rate of 1.8° C. / min under a nitrogen atmosphere and keeping the temperature for 1.3 h.

[0046] The medium-temperature activation in step 3 refers to raising the temperature to 595°C at a rate of 4.8°C / min and keeping the temperature for 2.2 hours.

[0047] The higher temperature treatment in step 3 refers to raising the temperature to 790°C at a rate of 2.6°C, maintaining the temperature for 0.55h, and introducing CO2 at a flow rate of 48mL / min.

[0048] The alkaline washing and silicon removal in step 4 refers to soaking in 1.8 mol / L sodium hydroxide solution for 5.7 hours and washing with deionized water until neutral.

[0049] The microwave-steam treatment in step 4 refers to 570W microwave irradiation for 2.8 minutes, while water vapor is introduced at a flow rate of 9 mL / min.

[0050] The porous carbon is applied to the treatment of organic dye wastewater and pharmaceutical wastewater.

[0051] Example 3

[0052] A method for preparing porous carbon having mesopores, the method comprising the following steps:

[0053] Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material;

[0054] Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material;

[0055] Step 3: pre-carbonizing the activated raw material at a relatively low temperature, activating it at a medium temperature, and treating it at a relatively high temperature to obtain a carbonized product;

[0056] Step 4: The carbonized product is subjected to alkali washing to remove silicon, and microwave-steam treatment to obtain porous carbon with mesopores.

[0057] The ball milling in step 1 refers to ball milling at a speed of 450 rpm for 3 hours; the acid washing refers to soaking in 1 mol / L hydrochloric acid solution for 2.5 hours and washing with deionized water until neutral; the drying temperature is 80°C.

[0058] In step 2, the mass ratio of the raw materials to the phosphoric acid solution is 1:1.5; the content of phosphoric acid in the phosphoric acid solution is 33wt%; the mixing refers to setting the ultrasonic frequency to 40kHz, the ultrasonic power to 350W, and the ultrasonication for 1h; the drying refers to drying at 120°C to constant weight.

[0059] The lower temperature pre-carbonization in step 3 refers to heating to 300° C. at a rate of 2° C. / min under a nitrogen atmosphere and keeping the temperature for 1.5 h.

[0060] The medium-temperature activation in step 3 refers to heating to 600°C at a rate of 5°C / min and keeping the temperature for 2.5 hours.

[0061] The higher temperature treatment in step 3 refers to raising the temperature to 800°C at a rate of 3°C, keeping the temperature for 0.6h, and introducing CO2 at a flow rate of 50mL / min.

[0062] The alkaline washing and silicon removal in step 4 refers to soaking in 2 mol / L sodium hydroxide solution for 6 hours and washing with deionized water until neutral.

[0063] The microwave-steam treatment in step 4 refers to 600 W microwave irradiation for 3 minutes, while water vapor is introduced at a flow rate of 10 mL / min.

[0064] The porous carbon is applied to the treatment of organic dye wastewater and pharmaceutical wastewater.

[0065] Example 4

[0066] A method for preparing porous carbon having mesopores, the method comprising the following steps:

[0067] Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material;

[0068] Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material;

[0069] Step 3: pre-carbonizing the activated raw material at a relatively low temperature, activating it at a medium temperature, and treating it at a relatively high temperature to obtain a carbonized product;

[0070] Step 4: The carbonized product is subjected to alkali washing to remove silicon, and microwave-steam treatment to obtain porous carbon with mesopores.

[0071] The ball milling in step 1 refers to ball milling at a speed of 470 rpm for 3.3 hours; the acid washing refers to soaking in 1.1 mol / L hydrochloric acid solution for 2.6 hours and washing with deionized water until neutral; the drying temperature is 80°C.

[0072] In step 2, the mass ratio of the raw materials to the phosphoric acid solution is 1:1.58; the content of phosphoric acid in the phosphoric acid solution is 34 wt%; the mixing refers to setting the ultrasonic frequency to 45 kHz, the ultrasonic power to 360 W, and the ultrasonication for 1.1 h; the drying refers to drying at 120° C. to constant weight.

[0073] The lower temperature pre-carbonization in step 3 refers to heating to 301° C. at a rate of 2.4° C. / min under a nitrogen atmosphere and keeping the temperature for 1.6 h.

[0074] The medium-temperature activation in step 3 refers to raising the temperature to 605°C at a rate of 5.2°C / min and keeping the temperature for 2.7 hours.

[0075] The higher temperature treatment in step 3 refers to raising the temperature to 810°C at a rate of 3.4°C, maintaining the temperature for 0.64h, and introducing CO2 at a flow rate of 52mL / min.

[0076] The alkaline washing and silicon removal in step 4 refers to soaking in 2.2 mol / L sodium hydroxide solution for 6.5 hours and washing with deionized water until neutral.

[0077] The microwave-steam treatment in step 4 refers to 630W microwave irradiation for 3.2 minutes, while water vapor is introduced at a flow rate of 11 mL / min.

[0078] The porous carbon is applied to the treatment of organic dye wastewater and pharmaceutical wastewater.

[0079] Example 5

[0080] A method for preparing porous carbon having mesopores, the method comprising the following steps:

[0081] Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material;

[0082] Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material;

[0083] Step 3: pre-carbonizing the activated raw material at a relatively low temperature, activating it at a medium temperature, and treating it at a relatively high temperature to obtain a carbonized product;

[0084] Step 4: The carbonized product is subjected to alkali washing to remove silicon, and microwave-steam treatment to obtain porous carbon with mesopores.

[0085] The ball milling in step 1 refers to ball milling at a speed of 500 rpm for 3.5 hours; the acid washing refers to soaking in 1.2 mol / L hydrochloric acid solution for 3 hours and washing with deionized water until neutral; the drying temperature is 80°C.

[0086] In step 2, the mass ratio of the raw materials to the phosphoric acid solution is 1:1.6; the content of phosphoric acid in the phosphoric acid solution is 35wt%; the mixing refers to setting the ultrasonic frequency to 50kHz, the ultrasonic power to 400W, and the ultrasonication for 1.2h; the drying refers to drying at 120°C to constant weight.

[0087] The lower temperature pre-carbonization in step 3 refers to heating to 302°C at a rate of 2.5°C / min under a nitrogen atmosphere and keeping the temperature for 2 hours.

[0088] The medium-temperature activation in step 3 refers to heating to 610°C at a rate of 5.5°C / min and keeping the temperature for 3 hours.

[0089] The higher temperature treatment in step 3 refers to raising the temperature to 820°C at a rate of 3.5°C, keeping the temperature for 0.7h, and introducing CO2 at a flow rate of 55mL / min.

[0090] The alkaline washing and silicon removal in step 4 refers to soaking in 2.5 mol / L sodium hydroxide solution for 7 hours and washing with deionized water until neutral.

[0091] The microwave-steam treatment in step 4 refers to 650W microwave irradiation for 3.5 minutes, while water vapor is introduced at a flow rate of 12 mL / min.

[0092] The porous carbon is applied to the treatment of organic dye wastewater and pharmaceutical wastewater.

[0093] Example 6

[0094] On the basis of Example 3, the content of phosphoric acid in the phosphoric acid solution was changed to 20 wt %, and other conditions remained the same as in Example 3.

[0095] Example 7

[0096] On the basis of Example 3, the content of phosphoric acid in the phosphoric acid solution was changed to 50 wt %, and the other conditions were the same as those in Example 3.

[0097] Comparative Example 1

[0098] On the basis of Example 3, keeping other conditions the same, the preparation method of porous carbon with mesopore size was changed to the following steps:

[0099] Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material;

[0100] Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material;

[0101] Step 3: Activate the activated raw material at medium temperature and then treat it at a higher temperature to obtain a carbonized product; the medium temperature activation here means heating the temperature to 600°C at a rate of 5°C / min and keeping the temperature for 4 hours;

[0102] Step 4: The carbonized product is subjected to alkali washing to remove silicon, and microwave-steam treatment to obtain porous carbon with mesopores.

[0103] Comparative Example 2

[0104] On the basis of Example 3, keeping other conditions the same, the preparation method of porous carbon with mesopore size was changed to the following steps:

[0105] Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material;

[0106] Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material;

[0107] Step 3: pre-carbonize the activated raw material at a relatively low temperature and then treat it at a relatively high temperature to obtain a carbonized product; the relatively high temperature treatment at this time refers to heating the material to 800°C at a rate of 3°C, maintaining the temperature for 3.1 hours, and introducing CO2 at a flow rate of 50 mL / min;

[0108] Step 4: The carbonized product is subjected to alkali washing to remove silicon, and microwave-steam treatment to obtain porous carbon with mesopores.

[0109] Comparative Example 3

[0110] On the basis of Example 3, keeping other conditions the same, the preparation method of porous carbon with mesopore size was changed to the following steps:

[0111] Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material;

[0112] Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material;

[0113] Step 3: pre-carbonizing the activated raw material at a relatively low temperature, activating it at a medium temperature, and treating it at a relatively high temperature to obtain a carbonized product;

[0114] Step 4: The carbonized product is subjected to alkali washing to remove silicon, and dried at 80° C. to obtain porous carbon with mesopore size.

[0115] Comparative Example 4

[0116] On the basis of Example 3, keeping other conditions the same, the low-temperature pre-carbonization operation was changed to: under a nitrogen atmosphere, the temperature was raised to 300° C. at a rate of 4.5° C. / min and kept at that temperature for 1.5 h.

[0117] Comparative Example 5

[0118] On the basis of Example 3, other conditions were kept the same, and the holding time of the medium-temperature activation was changed to 1 h.

[0119] Comparative Example 6

[0120] On the basis of Example 3, other conditions were kept the same, and the holding time of the medium temperature activation was changed to 4 h.

[0121] Comparative Example 7

[0122] On the basis of Example 3, other conditions were kept the same, and the flow rate of CO2 during the higher temperature treatment was changed to 20 mL / min.

[0123] Comparative Example 8

[0124] On the basis of Example 3, other conditions were kept the same, and the power during microwave-steam treatment was changed to 400W.

[0125] Comparative Example 9

[0126] On the basis of Example 3, other conditions were kept the same, and the power during microwave-steam treatment was changed to 800W.

[0127] The porous carbon prepared in Examples 1-7 and Comparative Examples 1-9 was used as a sample to test the mesopore diameter (average) and mesopore ratio. The test results are shown in Table 1 below.

[0128] Table 1

[0129]

[0130]

[0131] It can be seen from Table 1 that the mesopore diameter range of the porous carbon prepared by the present invention is stable in the range of 4.3±0.2nm, and the mesopore ratio is within 76-78%. Although the mesopore diameter and mesopore ratio of some comparative examples are higher than those of the embodiment, such as comparative example 9, the larger mesopore diameter and higher mesopore ratio are prone to collapse in actual application. In addition, the improvement of some numerical values is based on changes in preparation parameters, such as an increase in phosphoric acid concentration, an increase in power during microwave-steam treatment, etc., which can easily burden the equipment in actual operation, thereby increasing operating costs, etc. Therefore, compared with the comparative examples, the present application provides a porous carbon with mesopores and a relatively stable mesopore ratio, which has a lower cost and has good application prospects.

[0132] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any indirect modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for preparing porous carbon having mesopores, characterized in that: The method for preparing porous carbon having mesopores comprises the following steps: Step 1: ball-milling the rice husk, acid-washing to remove impurities, and drying to obtain the raw material; Step 2: mixing the raw material with the phosphoric acid solution and drying to obtain an activated raw material; Step 3: pre-carbonizing the activated raw material at a relatively low temperature, activating it at a medium temperature, and treating it at a relatively high temperature to obtain a carbonized product; Step 4: The carbonized product is subjected to alkali washing to remove silicon, and microwave-steam treatment to obtain porous carbon with mesopores.

2. The method for preparing porous carbon having mesopores according to claim 1, wherein: The ball milling in step 1 refers to ball milling at a speed of 400-500 rpm for 2.5-3.5 hours; the acid washing refers to soaking in 0.8-1.2 mol / L hydrochloric acid solution for 2-3 hours and washing with deionized water until neutral; the drying temperature is 80°C.

3. The method for preparing porous carbon having mesopore diameter according to claim 1, characterized in that: In step 2, the mass ratio of the raw materials to the phosphoric acid solution is 1:1.4-1.6; the content of phosphoric acid in the phosphoric acid solution is 31-35wt%; the mixing refers to setting the ultrasonic frequency to 30-50kHz, the ultrasonic power to 300-400W, and the ultrasonication for 0.8-1.2h; and the drying refers to drying at 120°C to constant weight.

4. The method for preparing porous carbon having mesopores according to claim 1, wherein: The lower temperature pre-carbonization in step 3 refers to heating to 298-302°C at a rate of 1.5-2.5°C / min under a nitrogen atmosphere and keeping the temperature for 1-2 hours.

5. The method for preparing porous carbon having mesopore diameter according to claim 1, characterized in that: The medium-temperature activation in step 3 refers to heating to 590-610°C at a rate of 4.5-5.5°C / min and keeping the temperature for 2-3 hours.

6. The method for preparing porous carbon having mesopore diameter according to claim 1, characterized in that: The higher temperature treatment in step 3 refers to raising the temperature to 780-820°C at a rate of 2.5-3.5°C, maintaining the temperature for 0.5-0.7h, and introducing CO2 at a flow rate of 45-55mL / min.

7. The method for preparing porous carbon having mesopores according to claim 1, wherein: The alkaline washing and silicon removal in step 4 refers to soaking in 1.5-2.5 mol / L sodium hydroxide solution for 5-7 hours and washing with deionized water until neutral.

8. The method for preparing porous carbon having mesopores according to claim 1, wherein: The microwave-steam treatment in step 4 refers to microwave irradiation at 550-650W for 2.5-3.5 minutes, while simultaneously introducing water vapor at a flow rate of 8-12 mL / min.

9. Use of porous carbon prepared by the method for preparing porous carbon with mesopores according to any one of claims 1 to 8, characterized in that: The porous carbon is applied to the treatment of organic dye wastewater and pharmaceutical wastewater.

Images