Treatment process for preparing microporous carbon from waste sulfuric acid

Abstract

The invention belongs to the technical field of waste sulfuric acid resource utilization, and provides a treatment process for preparing microporous carbon from waste sulfuric acid, the waste sulfuric acid is alkylated waste sulfuric acid or waste sulfuric acid containing long-chain structure C8 or above organic matters, and the treatment process comprises the following steps: S1, a hydrated precipitated carbon reaction stage; s2, an aging microporous carbon reaction stage; s3, a separation stage: mixing the solid material generated in S2 with clear water in proportion, washing and separating to obtain microporous carbon A and purified acid; and S4, tail gas treatment. The waste sulfuric acid with high organic matter content is used for preparing the microporous carbon and the purified acid, the purified acid can be used for preparing sulfate, tail gas is reasonably treated, particularly, the microporous carbon can be used as a fuel and an adsorbent of the organic matter, complex and high-cost equipment investment and raw material investment are not needed, and the cost is low. Reduction, recycling and energy reduction of resources can be realized, and products with high additional values can be obtained.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of resource utilization of waste sulfuric acid, and particularly relates to a treatment process for preparing microporous carbon from waste sulfuric acid. BACKGROUND

[0002] At present, in industrial practice, the treatment of waste sulfuric acid has problems in process to varying degrees, as follows: Regarding the disposal of waste sulfuric acid, there are high treatment cost, high equipment investment, serious resource waste, secondary pollution risk, great difficulty in treatment, safety hazard, and large energy consumption. The commonly used waste sulfuric acid treatment processes mainly include the following: ① High-temperature cracking method: waste sulfuric acid is cracked at a high temperature of more than 1000℃ in a incinerator to generate sulfur dioxide gas, which is recovered into 98% industrial sulfuric acid after catalytic conversion. The disadvantages are: the treatment cost and benefit are reversed, the production cost of each ton of sulfuric acid is about 700 yuan when sulfur resources are recovered by high-temperature cracking, while the market price of sulfuric acid is only 300-400 yuan / ton, and enterprises have no economic motivation; the energy consumption is huge, the equipment is easy to corrode, and the environmental pollution risk is high; ② Neutralization method: using magnesium oxide, lime or lye to neutralize waste acid to generate magnesium sulfate, calcium sulfate and other sulfate. The disadvantages are: if waste sulfuric acid is used to produce magnesium sulfate, the harmless treatment cost increases by thousands of yuan per ton, but the market price of similar products is only 200-300 yuan / ton, leading to vicious competition; if lime is used for neutralization, a large amount of waste residue is generated, the resource utilization rate is low: the sulfuric acid is not recovered, which does not comply with the principle of circular economy; ③ Oxidation-adsorption combined method: first, using an oxidizing agent (such as hydrogen peroxide) to decompose ASO, and then adsorbing the remaining organic matter by activated carbon. The disadvantages are: the cost of oxidizing agent is high, the economic benefit is poor, and the regeneration of activated carbon is difficult.

[0003] ④ Organic waste sulfuric acid carbonization reduction: mixing high-concentration organic waste sulfuric acid and other organic waste, controlling the reaction temperature at about 200℃, using the strong oxidizing property of high-temperature concentrated sulfuric acid to dehydrate and carbonize the organic matter in waste sulfuric acid into sulfonated carbon, and reducing sulfuric acid to sulfur dioxide under the action of organic carbon. The disadvantages are: high reaction temperature, not only high energy consumption but also high requirements for equipment material; low recovery rate of sulfuric acid and carbon, more sulfur dioxide generated, increasing the burden of tail gas treatment stage; the pore diameter of prepared sulfonated carbon is large, affecting the adsorption effect, especially for small molecule organic matter interception. SUMMARY

[0004] The present application proposes a treatment process for preparing microporous carbon from waste sulfuric acid, which can realize the reduction, resource utilization and energy reduction of resources, and is conducive to obtaining high-value-added products.

[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is that the present application provides a treatment process for preparing microporous carbon from waste sulfuric acid, wherein the waste sulfuric acid is alkylation waste sulfuric acid or waste sulfuric acid containing long-chain structure carbon 8 or more organic matter, and the treatment process comprises the following steps: S1, a hydration and precipitation carbon reaction stage; S2, an aging microporous carbon reaction stage; S3, a separation stage, wherein the solid material generated in S2 is mixed with clean water in a certain proportion, washed, and separated to obtain microporous carbon A and purified acid, the microporous carbon A is used as fuel and an organic matter adsorbent, and the purified acid is used for producing a sulfate; and S4, tail gas treatment.

[0006] Preferably, in step S1, the waste sulfuric acid is adjusted to a concentration > 80% with high-concentration sulfuric acid, and slowly heated to 120-130°C at a temperature rising rate of 1°C / min, and the strong oxidizing property of the concentrated sulfuric acid causes the organic matter in the alkylation waste sulfuric acid to precipitate in the form of small-molecule carbon, thereby obtaining small-molecule carbon chains with multiple active sites, large specific surface area, and amorphous.

[0007] Preferably, in step S2, the temperature is raised to 140-170°C, the temperature rising control is 0.16°C / min, and the temperature rising time is 3 hours, and in the high-acid environment, the small-molecule carbon chains generated in S1 grow into microporous carbon with multiple active sites, large specific surface area, and granular shape.

[0008] Preferably, in step S3, the number of times of clean water washing is not less than 3, and the components for producing the sulfate include, in addition to the purified acid, ammonia gas, harmless aluminum ash, and magnesium-containing slag.

[0009] Preferably, the absorbable waste gas generated in steps S1 and S2 enters a tail gas absorption system, and the absorbable waste gas at least includes SO2 and H2S; and the organic combustible waste gas generated in steps S1 and S2 is sent to a hot blast stove for combustion.

[0010] Preferably, in steps S1 and S2, the waste sulfuric acid completes the reactions of small-molecule carbon and microporous carbon in a reaction kettle in sequence, the reaction kettle is provided with a material level detection device for detecting the precipitated material level in the waste sulfuric acid, the material level detection device comprises a static tube, the static tube comprises a tube body, a spiral collection groove is arranged on the side wall of the tube body, the spiral length of the spiral collection groove is 1 pitch and the pitch is 10-60 cm, a reduced diameter port is arranged at the top of the tube body, a sealing convex lens is arranged at the top of the reduced diameter port, the inner diameter of the reduced diameter port is greater than the minimum groove center distance from the spiral collection groove to the center of the tube body, a eyepiece tube connected with the reduced diameter port is arranged at the top of the static tube, and an industrial camera is arranged at the top of the eyepiece tube, the industrial camera is used for feeding back the collected images to the control cabinet of the workshop.

[0011] As preferred, the bottom of the pipe body is provided with a diameter expansion opening, a bottom plug is arranged in the diameter expansion opening and is screwed with the diameter expansion opening, the top surface of the bottom plug is provided with a sink, and a circular bottom color plate is arranged in the sink, the diameter of the bottom color plate is larger than the minimum slot center distance from the spiral collection slot to the center of the pipe body.

[0012] As preferred, the side surface of the bottom plug is provided with an internal hexagonal blind hole, the bottom surface of the bottom plug is provided with an annular groove, the bottom of the annular groove is provided with a sealing ring, and the inner bottom of the reaction kettle is provided with a support column matched with the support of the bottom plug.

[0013] As preferred, the vertical section shape of the spiral collection slot is a right trapezoid, and the oblique waist side of the right trapezoid is located below the right angle side.

[0014] As preferred, the top of the reaction kettle is provided with a flange for mounting an ocular tube, a cooling jacket is arranged between the ocular tube and the flange, the cooling jacket is connected with the flange through bolts, and a bushing is arranged between the cooling jacket and the nesting surface of the ocular tube.

[0015] Compared with the prior art, the application has the advantages and positive effects that: The treatment process for preparing microporous carbon from waste sulfuric acid provided by the application uses waste sulfuric acid containing high organic matter to prepare microporous carbon and purify acid, the purified acid can be used to prepare sulfate, tail gas is also reasonably treated, especially the microporous carbon can be used as fuel and an adsorbent for organic matter, without complex and high-cost equipment investment and raw material investment, the treatment process can realize resource reduction, resource utilization and energy reduction, and high-value-added products can be obtained. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0017] Figure 1 It is a schematic diagram of a treatment process for preparing microporous carbon from waste sulfuric acid; Figure 2 It is a laboratory reaction test diagram of Example 1-Example 4; Figure 3 It is a comparison diagram of decolorization and de-organic matter effects of microporous carbon A and activated carbon; Figure 4 It is a distribution schematic diagram of the level detection device in the reaction kettle; Figure 5 It is a perspective view of the level detection device; Figure 6This is a cross-sectional view of the material level detection device; Figure 7 for Figure 6 Enlarged schematic diagram of the material level detection device at point A; Figure 8 for Figure 6 Enlarged schematic diagram of the material level detection device at point B; In the above figures: 1. Reactor; 11. Support column; 12. Flange; 2. Material level detection device; 21. Static pipe; 211. Pipe body; 212. Spiral collection groove; 213. Reduction port; 214. Expansion port; 22. Sealing convex lens; 23. Eyepiece tube; 24. Industrial camera; 25. Bottom plug; 251. Settling tank; 252. Internal hexagon blind hole; 26. Background color plate; 27. Sealing ring; 3. Cooling jacket; 4. Bushing. Detailed Implementation

[0018] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other. For ease of description, the terms "upper," "lower," "left," and "right" appearing below only indicate that they correspond to the upper, lower, left, and right directions in the accompanying drawings and do not limit the structure.

[0019] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways than those described herein, and therefore the invention is not limited to the specific embodiments disclosed in the following specification.

[0020] Example 1, such as Figures 1-3 As shown, the present invention provides a process for preparing microporous carbon from waste sulfuric acid, wherein the waste sulfuric acid is alkylated waste sulfuric acid or waste sulfuric acid containing organic matter with a long chain structure of more than 8 carbon atoms, and includes the following steps: S1, hydrated precipitated carbon reaction stage; S2, aged microporous carbon reaction stage; S3, separation stage; S4, tail gas treatment.

[0021] Specifically, in step S1, the waste sulfuric acid is adjusted to a concentration >80% with high-concentration sulfuric acid, and slowly heated to 120-130℃ at a heating rate of 1℃ / min, with the stirring speed controlled at 100r / min. The entire heating process takes about 2 hours. After reaching the temperature, it is kept at the temperature for 1 hour. The strong oxidizing property of concentrated sulfuric acid causes the organic matter in the alkylated waste sulfuric acid to precipitate out in the form of small molecule carbon, resulting in small molecule carbon chains with multiple active sites, large specific surface area, and amorphous shape.

[0022] In step S2, the temperature is raised to 140℃, the temperature rising control is 0.16℃ / min, the stirring speed is 50r / min, the temperature rising time is 3 hours, and the small molecule carbon chains generated from S1 grow into microporous carbon with multiple active sites, large specific surface area and granular shape in a high acid environment; the solid weight loss is 5.5%.

[0023] In step S3, the solid material generated in S2 is mixed with clean water at a ratio of 1:1, washed, separated, to obtain microporous carbon A and purified acid, the microporous carbon A is used as fuel and organic adsorbent, and the purified acid is used for producing sulfate; the clean water washing times of the sulfate are not less than 3 times, and the components for producing the sulfate include ammonia, harmless aluminum ash and magnesium-containing slag in addition to the purified acid; the yield of the microporous carbon A, i.e. sulfonated carbon, after drying at 105℃ is 3.9%.

[0024] The absorbable waste gas generated in steps S1 and S2 enters the tail gas absorption system, and the absorbable waste gas at least includes SO2 and H2S; the organic combustible waste gas generated in steps S1 and S2 is sent into the hot blast stove for combustion. Example 2

[0025] The process is the same as that in example 1, wherein the changed condition is that in S2, the temperature is raised to 150℃, and other conditions are the same; the solid weight loss rate in step S2 is 7.2%; the yield of the microporous carbon A, i.e. sulfonated carbon, after drying at 105℃ is 5.1%. Example 3

[0026] The process is the same as that in example 1, wherein the changed condition is that in S2, the temperature is raised to 160℃, and other conditions are the same; the solid weight loss rate in step S2 is 9.5%; the yield of the microporous carbon A, i.e. sulfonated carbon, after drying at 105℃ is 7.3%. Example 4

[0027] The process is the same as that in example 1, wherein the changed condition is that in S2, the temperature is raised to 170℃, and other conditions are the same; the solid weight loss rate in step S2 is 18.5%; the yield of the microporous carbon A, i.e. sulfonated carbon, after drying at 105℃ is 9.5%. Example 5

[0028] The process is the same as that in example 1, wherein the changed condition is that in S2, the temperature is raised to 190℃, and other conditions are the same.

[0029] In embodiments 1-4, the purpose of slow temperature rise in step S1 is to improve the utilization efficiency of waste concentrated sulfuric acid, reduce the occurrence of side reactions due to local overheating and rapid temperature rise, and reduce the instantaneous temperature to a high level, which can cause the reduction of concentrated sulfuric acid, the generation of a large amount of sulfur dioxide and hydrogen sulfide hazardous gas, and the reduction of sulfuric acid recovery rate; in step S2, in a high acid environment, the amorphous small molecular carbon chain generated in S1 stage is slowly removed from the active site, so that the amorphous carbon chain is grown into microporous carbon with multiple active sites, large specific surface area, small particles and strong adsorption; strict temperature control can effectively improve the formation of microporous structure, and reduce the generation of more by-products due to severe temperature fluctuations, and reduce the decomposition loss of sulfuric acid.

[0030] The processing technology for preparing microporous carbon from waste sulfuric acid provided by the application uses waste sulfuric acid containing high organic matter to prepare microporous carbon and purified acid, the purified acid can be used to prepare sulfate, the tail gas is also reasonably treated, especially the microporous carbon can be used as a fuel and an organic matter adsorbent, without the need for complex and high-cost equipment investment and raw material investment, the resource reduction, resource utilization and energy reduction can be realized, and high-value-added products can be obtained. The application solves the problem of large organic waste gas emission in the disposal process of waste sulfuric acid from the source, solves the problem of serious corrosion of waste sulfuric acid on multiple devices due to the use of a large number of treatment devices, and is conducive to controlling the process treatment cost.

[0031] As shown in Figure 3 , the adsorption effect comparison of microporous carbon A and activated carbon in embodiments 1-4 is shown in the table, it is found through comparison that the adsorption effect of microporous carbon A and activated carbon with an addition ratio of 5% is better than that with an addition ratio of less than 5%, and the adsorption effect of microporous carbon A is better than that of activated carbon under the same addition ratio. The reason why the adsorption effect of microporous carbon A is better than that of activated carbon is that microporous carbon A has a microporous structure, a large number of organic phase active sites, and good "phase recognition and compatibility" performance, which can significantly improve the decolorization and organic matter removal effect of other waste sulfuric acid. The application improves the reaction mechanism compared with the traditional adsorption, greatly improves the decolorization and organic matter removal effect of organic acid, and thus provides a simple and low-cost waste sulfuric acid regeneration.

[0032] As shown in Figures 2-3 , the color of the alkylated waste sulfuric acid in the original state is deep, and it is difficult to grasp the progress of the reaction of small molecular carbon and microporous carbon in steps S1 and S2, in order to improve the reaction progress in the industrialized and large-scale treatment of alkylated waste sulfuric acid, the application provides a device that can improve the progress detection efficiency, specifically as shown in Figures 4-8As shown, in steps S1 and S2, the reaction of small molecule carbon and microporous carbon in waste sulfuric acid is completed in the reaction kettle 1, the reaction kettle 1 is provided with a material level detection device 2 for detecting the material level of the precipitated sediment in the waste sulfuric acid, the material level detection device 2 comprises a static tube 21, the static tube 21 comprises a tube body 211, a spiral collection groove 212 is arranged on the side wall of the tube body 211, the spiral length of the spiral collection groove 212 is 1 pitch and the pitch is 10-60 cm, a reduced diameter port 213 is arranged at the top of the tube body 211, a sealing convex lens 22 is arranged at the top of the reduced diameter port 213, the inner diameter of the reduced diameter port 213 is greater than the minimum groove center distance from the spiral collection groove 212 to the center of the tube body 211, an eyepiece tube 23 connected with the reduced diameter port 213 is arranged at the top of the static tube 21, the outer wall of the tube body of the eyepiece tube is coated with a wear-resistant, high-temperature-resistant and sulfuric acid corrosion-resistant coating, the coating covers an area that can provide a relatively closed shooting path inside the eyepiece tube, an industrial camera 24 with a light source is arranged at the top of the eyepiece tube 23, the light source is emitted from the head end of the industrial camera, the industrial camera 24 collects the dark band image of the spiral collection groove in the vertical projection direction inside the static tube, and the collected image is fed back to the control cabinet of the workshop through a transmission line.

[0033] The reaction kettle 1 has a wall sleeve, a pressure gauge, a thermometer, an inlet and outlet pipe and a stirring device, and the device for extending into the material in the reaction kettle 1 is made of anticorrosive material; in the reaction kettle 1, the material level detection device 2 is eccentrically arranged in the reaction kettle 1 and is close to the inner wall of the reaction kettle 1, and the small molecule carbon and microporous carbon generated in the reaction in S1 and S2 can fall into the spiral collection groove 212 under the precipitation effect, and the horizontal position of the precipitated components in the spiral collection groove 212 is basically consistent with the highest level of all the precipitated components in the reaction kettle 1; the industrial camera 24 can vertically collect the image in the static tube 21 outside the reaction kettle 1, and due to the gradual progress of the reaction, the color depth of the liquid above the precipitation level becomes lighter, and the relatively dark precipitated components form a dark band with a certain radial width in the spiral collection groove 212, and the vertical projection image of the dark band can be collected by the industrial camera 24; due to the spiral characteristics of the dark band on the static tube 21, one complete pitch occupies a 360° vertical projection surface, and the actual length of the dark band on the vertical projection is in a certain proportion to the height level of the reaction kettle 1, and then the control system of the control cabinet can be used to convert into the corresponding material level value, and the proportional conversion program is a mature technology, which will not be described herein; if the vertical projection arc length and the material level value of the dark band do not change within a certain time, it means that the reaction of this step is basically completed. In this way, the material level of the dark precipitate can be collected by the industrial camera 24, which can help the workshop to effectively control the progress of the reaction, and the static tube 21 can use a commonly used sulfuric acid corrosion resistant material such as a glass tube, which has good corrosion resistance, low cost, and does not require additional sensors, so it can also eliminate the influence of high temperature in the reaction kettle 1 on the detection performance of the sensor, has good material level detection performance, strong adaptability and high utilization rate.

[0034] In order to improve the detection performance of the material level detection device 2, the static tube 21 with anticorrosion performance is used as the device for immersing into the material; the eyepiece tube 23 plays a role in extending the detection distance of the industrial camera 24, especially the volume of the precipitated components is significantly smaller than that of the waste sulfuric acid, and the industrial camera 24 can be installed through the eyepiece tube 23 to ensure that the industrial camera 24 can complete image collection outside the reaction kettle 1; the sealing convex lens 22 can seal the tube body 211 and also acts as a magnifying glass to enlarge the area of the vertical projection range of the spiral collection groove 212 into the eyepiece tube 23, which is conducive to improving the recognition performance of the collected image of the industrial camera 24, especially the recognition accuracy of the light and dark bands with color difference, thereby improving the material level detection performance of the dark precipitated components.

[0035] Further, the bottom of the pipe body 211 is provided with an expanded diameter opening, and a bottom plug 25 is threadedly connected to the expanded diameter opening, the top surface of the bottom plug 25 is provided with a sunken groove 251, and a circular bottom color plate 26 is arranged in the sunken groove 251, the bottom color plate 26 can adopt a color that is different from the liquid and the precipitate, and the diameter of the bottom color plate 26 is greater than the minimum groove center distance from the spiral collection groove 212 to the center of the pipe body 211. The bottom plug 25 can be used to finely adjust the contact quality between the static settling pipe 21 and the bottom of the reaction kettle 1, the bottom plug 25 cuts off the position of the dark precipitate entering the collection area of the industrial camera 24, and provides the contrast between the bottom color plate 26 and the dark precipitate, and also provides the obvious contrast with the liquid changing from dark to light, which is beneficial to improve the collection image performance of the industrial camera 24, thereby improving the reliability of mastering the reaction progress inside the reaction kettle 1.

[0036] In order to conveniently adjust the bottom plug 25, the side surface of the bottom plug 25 is provided with an internal hexagonal blind hole 252, and a hexagonal wrench can be used to adjust the contact condition between the bottom plug 25 and the bottom of the reaction kettle 1, and the hand holding end of the hexagonal wrench can be designed to be long, so that when the material level detection device 2 is in place, the corresponding adjustment operation can be completed outside the reaction kettle 1. Further, the bottom surface of the bottom plug 25 is provided with an annular groove, the bottom of the annular groove is provided with a sealing ring 27, the inner bottom of the reaction kettle 1 is provided with a support column 11 that supports the bottom plug 25, the top surface of the support column 11 is a plane, the bottom plug 25 and the sealing ring 27 are used to effectively support the bottom of the static settling pipe 21 on the support column 11, effectively cut off the gathering channel of the dark precipitate in the vertical projection range of the static settling pipe 21, and the sealing ring 27 can also provide certain buffering and balancing support performance for the static settling pipe 21, which is beneficial to improve the connection reliability of the static settling pipe 21 and the ocular tube 23, and reduce the probability of liquid leaking from the matching surface of the static settling pipe 21 and the ocular tube 23 into the ocular tube 23.

[0037] In order to improve the material level detection accuracy of the dark precipitate in the reaction kettle 1, the vertical cross-sectional shape of the spiral collection groove 212 is a right trapezoid, and the oblique waist side of the right trapezoid is located below the right angle side. In this way, the dark precipitate that falls from top to bottom can enter the spiral collection groove 212 in advance, but can also complete the final precipitation along the path of the spiral collection groove 212, and the precipitate higher than the overall precipitate level will continue to fall along the inclined surface part of the spiral collection groove 212 under the action of gravity and fall into the precipitate bed, thereby reducing the height difference between the precipitate in the spiral collection groove 212 and the precipitate in other positions, and improving the collection accuracy of the actual dark band by the industrial camera 24.

[0038] In order to improve the detection performance of the industrial camera 24, the top of the reaction kettle 1 is provided with a flange 12 for mounting the ocular tube 23, a cooling jacket 3 is arranged between the ocular tube 23 and the flange 12, the top of the ocular tube 23 is provided with a top ring limitedly matched with the top surface of the cooling jacket 3, the cooling jacket 3 is connected with the flange 12 through bolts, and a bushing 4 is arranged between the nested surface of the cooling jacket 3 and the ocular tube 23. Wherein, the top of the ocular tube 23 is designed as a sunk port to mount the collection end of the industrial camera 24, the cooling jacket 3 is designed as a wall sleeve, and cooling liquid is arranged in the cooling jacket 3 to cool the position of the ocular tube 23 mounting the industrial camera 24, so as to reduce the temperature difference between the outside of the reaction kettle 1 and the end of the ocular tube 23, the bushing 4 is made of heat insulation material, which can not only insulate heat but also seal the matching surface of the ocular tube and the cooling jacket to effectively avoid the industrial camera 24 from being obviously heated by the reaction temperature in the reaction kettle 1, so as to improve the image collection performance of the industrial camera 24 and the control performance of the reaction progress in the reaction kettle 1.

[0039] The above is only the preferred embodiment of the present application, and is not intended to limit the present application in other forms. Any skilled person in the art can modify or change the above disclosed technical content into equivalent embodiments applied to other fields, but any simple modification, equivalent change and modification made according to the technical essence of the present application to the above embodiments without departing from the technical solution of the present application shall still fall within the protection scope of the present application.

Claims

1. A treatment process for preparing microporous carbon from waste sulfuric acid, the waste sulfuric acid being waste sulfuric acid from alkylation or waste sulfuric acid containing long-chain structural carbon-8 or more organic matter, characterized by, It comprises the following steps: S1, hydration and precipitation of carbon reaction stage; S2, aging microporous carbon reaction stage; S3, separation stage, the solid material produced in S2 is mixed with clean water in proportion, washed, separated, to obtain microporous carbon A and purified acid, the microporous carbon A is used as fuel and organic adsorbent, and the purified acid is used for producing sulfate; S4, tail gas treatment.

2. A process for the preparation of microporous carbon from spent sulfuric acid according to claim 1, characterized in that, In step S1, the waste sulfuric acid is adjusted to a concentration >80% with high-concentration sulfuric acid, and slowly heated to 120-130℃ at a temperature rising rate of 1℃ / min, the strong oxidizing property of concentrated sulfuric acid causes the organic matter in the alkylated waste sulfuric acid to precipitate in the form of small-molecule carbon, to obtain small-molecule carbon chains with multiple active sites, large specific surface area and amorphous.

3. The treatment process for preparing microporous carbon from waste sulfuric acid according to claim 2, characterized in that, In step S2, the temperature is raised to 140-170℃, the temperature rising is controlled at 0.16℃ / min, and the temperature rising time is 3 hours, under the high-acid environment, the small-molecule carbon chains generated in S1 grow into microporous carbon with multiple active sites, large specific surface area and granular shape.

4. The treatment process for preparing microporous carbon from waste sulfuric acid according to claim 3, characterized in that, In step S3, the number of clean water washing is not less than 3 times, and the components for producing sulfate include ammonia, harmless aluminum ash and magnesium-containing slag in addition to the purified acid.

5. The treatment process for preparing microporous carbon from waste sulfuric acid according to claim 4, characterized in that, The absorbable waste gas produced in steps S1 and S2 enters the tail gas absorption system, and the absorbable waste gas at least includes SO2 and H2S; the organic combustible waste gas produced in steps S1 and S2 is sent into the hot blast furnace for combustion.

6. The process for preparing microporous carbon from spent sulfuric acid according to any one of claims 1 to 5, characterized in that, In steps S1 and S2, the waste sulfuric acid completes the reactions of small-molecule carbon and microporous carbon in the reaction kettle, the reaction kettle is provided with a material level detection device for detecting the precipitated material level in the waste sulfuric acid, the material level detection device comprises a static tube, the static tube comprises a tube body, a spiral collection groove is arranged on the side wall of the tube body, the spiral length of the spiral collection groove is 1 pitch and the pitch is 10-60 cm, a reduced diameter port is arranged at the top of the tube body, a sealing convex lens is arranged at the top of the reduced diameter port, the inner diameter of the reduced diameter port is greater than the minimum groove center distance from the spiral collection groove to the center of the tube body, a eyepiece tube connected with the reduced diameter port is arranged at the top of the static tube, and an industrial camera is arranged at the top of the eyepiece tube, the industrial camera is used to feed back the collected images to the control cabinet of the workshop.

7. The treatment process for preparing microporous carbon from waste sulfuric acid according to claim 6, characterized in that, A flared port is arranged at the bottom of the tube body, a bottom plug is arranged in the flared port and connected with the flared port through threads, a sink groove is arranged on the top surface of the bottom plug, and a circular bottom color plate is arranged in the sink groove, the diameter of the circular bottom color plate is greater than the minimum groove center distance from the spiral collection groove to the center of the tube body.

8. The treatment process for preparing microporous carbon from waste sulfuric acid according to claim 7, characterized in that, An inner hexagonal blind hole is arranged on the side surface of the bottom plug, an annular groove is arranged on the bottom surface of the bottom plug, a sealing ring is arranged at the bottom of the annular groove, and a supporting column for supporting the bottom plug is arranged on the inner bottom of the reaction kettle.

9. The treatment process for preparing microporous carbon from waste sulfuric acid according to claim 7 or 8, characterized in that, The vertical cross-sectional shape of the spiral collection groove is a right-angled trapezoid, and the oblique waist side of the right-angled trapezoid is located below the right-angled side.

10. The treatment process for preparing microporous carbon from spent sulfuric acid according to claim 9, characterized in that, A flange for installing the eyepiece tube is arranged at the top of the reaction kettle, a cooling jacket is arranged between the eyepiece tube and the flange, the cooling jacket is connected with the flange through bolts, and a bushing is arranged between the nesting surface of the cooling jacket and the eyepiece tube.

Images