Method and system for removing peculiar smell through hollow activated carbon supported catalyst

Abstract

The invention provides a method and system for removing peculiar smell by using a hollow activated carbon supported catalyst, and the method comprises the following steps: step 1, obtaining a carbonaceous raw material, pretreating the carbonaceous raw material, and crushing the pretreated carbonaceous raw material; the composite catalyst and the activated carbon are tightly combined by using an impregnation method, a coprecipitation method and a sol-gel method, so that the agglomeration or falling phenomenon in use is effectively reduced, and the catalytic activity and the stability of a peculiar smell removal effect are improved; through physical activation and chemical activation, the specific surface area, pore structure and surface functional groups of the activated carbon are accurately regulated and controlled, a good foundation is laid for catalyst loading, meanwhile, the adsorption capacity of the activated carbon to peculiar smell is greatly enhanced, and the defect that the activated carbon is insufficient in performance is overcome; through close cooperation of all the modules, efficient integration of peculiar smell collection, treatment and emission links is achieved, the operation efficiency of the whole peculiar smell removal system is improved, and the urgent requirement of people for efficient peculiar smell removal is met.

Description

Technical Field

[0001] The invention relates to the technical field of odor treatment, and in particular to a method and a system for removing odor by using a hollow activated carbon loaded catalyst. Background Art

[0002] In today's society, odor problems are common and have serious impacts in daily life and industrial production. In daily life, indoor decoration materials, furniture, kitchens, bathrooms, etc. are odor-prone places. For example, decoration materials release VOCs, kitchens have fumes and food residue odors, and bathrooms have sewer and excrement odors. In industrial production, chemical companies emit waste gas containing pungent gases such as hydrogen sulfide, pharmaceutical companies have odors and potential risks of organic solvents and other volatile substances, and sewage treatment plants produce odorous gases by decomposition of organic matter, all of which have a great negative impact on people's lives and the environment. For a long time, people have tried to use a variety of traditional methods to deal with odor problems. In recent years, hollow activated carbon-loaded catalyst technology has gradually entered people's field of vision and attracted attention. However, judging from the current state of technological development, this technology still has many problems that need to be solved.

[0003] 1. In terms of catalyst loading stability, the catalyst is not firmly attached to the hollow activated carbon and is prone to agglomeration or falling off during use, thereby reducing the catalytic activity and deodorization effect;

[0004] Second, the optimization of activated carbon performance has not yet reached an ideal state. There is still a lot of room for improvement in its specific surface area, pore structure, surface functional groups and other characteristics. These factors directly affect the catalyst loading effect and odor adsorption capacity;

[0005] 3. In terms of system integration and application, the existing technology fails to efficiently integrate the collection, treatment and emission of odor, resulting in low operating efficiency of the entire odor removal system. It is difficult to give full play to the advantages of hollow activated carbon-loaded catalyst technology, and it is far from meeting people's urgent needs for efficient odor removal.

[0006] Therefore, a method and system for removing odor by using hollow activated carbon loaded catalyst are proposed. Summary of the invention

[0007] In view of this, the embodiments of the present invention hope to provide a method and system for removing odors using a hollow activated carbon-loaded catalyst to solve or alleviate the technical problems existing in the prior art and at least provide a beneficial option.

[0008] In order to solve the above technical problems, a technical solution adopted in the present application is: a method for removing odor by using a hollow activated carbon supported catalyst, comprising the following steps:

[0009] Step 1: obtaining a carbonaceous raw material, pre-treating the carbonaceous raw material, and crushing the pre-treated carbonaceous raw material;

[0010] Step 2: Put the crushed carbonaceous raw material into a carbonization furnace and perform carbonization under the protection of inert gas to gradually decompose the organic matter in the carbonaceous raw material to form a carbon structure. After the carbonization is completed, a carbonized product is obtained;

[0011] Step 3: Activating the carbonized product by physical activation or chemical activation to form a hollow structure and pores to obtain hollow activated carbon with adsorption performance;

[0012] Step 4: obtaining two or more catalyst components having synergistic effects, preparing single-component catalysts respectively, and mixing them in a certain proportion to obtain a composite catalyst precursor;

[0013] Step 5: loading the composite catalyst precursor on the hollow activated carbon by an impregnation method, a coprecipitation method or a sol-gel method to obtain a hollow activated carbon loaded with the catalyst;

[0014] Step 6: Fill the hollow activated carbon loaded with the catalyst into the reaction device, and control the reaction temperature, reaction humidity and gas flow rate according to the source and concentration of the odorous gas, so that the odorous gas and the hollow activated carbon loaded with the catalyst can fully contact and react;

[0015] Step 7: Use a gas chromatograph or a gas sensor to regularly detect the concentration of odorous substances in the gas after the reaction, record the removal rate data at different times, and optimize and adjust the reaction conditions and catalyst loading according to the test results.

[0016] As a further preferred embodiment of the present technical solution, in step three, the physical activation is performed by using water vapor or carbon dioxide gas as an activator to react with the carbonization product at high temperature, so that the gas molecules erode the carbon structure to form pores of various sizes, thereby obtaining hollow activated carbon with adsorption performance;

[0017] The chemical activation uses chemical reagents to react with carbonization products at high temperature to etch the carbon structure to form pores of various sizes, thereby obtaining hollow activated carbon with adsorption properties.

[0018] As a further preferred embodiment of the present technical solution, in step 5, the impregnation method is to immerse the hollow activated carbon in a solution containing a catalyst precursor so that the catalyst precursor is adsorbed on the activated carbon, and then dried and calcined to obtain a hollow activated carbon loaded with a catalyst;

[0019] The co-precipitation method is to add the hollow activated carbon and the catalyst precursor to the precipitant solution at the same time, so that the catalyst precursor is precipitated on the surface and in the pores of the activated carbon, and then dried and calcined to obtain the hollow activated carbon loaded with the catalyst;

[0020] The sol-gel method is to dissolve the catalyst precursor in a solvent to form a sol, then add the hollow activated carbon into the sol to gel the sol on the surface and pores of the activated carbon, and obtain the hollow activated carbon loaded with the catalyst after drying and calcination.

[0021] As a further preferred embodiment of the present technical solution, in step four, the synergistic catalyst component includes a precious metal catalyst component and a transition metal oxide catalyst component, wherein the precious metal catalyst component is one or more of platinum, palladium, and rhodium, and the transition metal oxide catalyst component is one or more of copper oxide, manganese oxide, and iron oxide.

[0022] As a further preferred embodiment of the present technical solution, in step one, the carbonaceous raw material includes coconut shell, fruit shell, and coal; and the pretreatment of the carbonaceous raw material includes screening treatment, washing treatment, and drying treatment.

[0023] As a further preferred embodiment of the present technical solution, in step 2, the carbonization is carried out under the protection of an inert gas, wherein the heating rate of the carbonization process is 3-8°C / minute, the carbonization temperature is maintained at 450-550°C, the carbonization time is 1.5-2.5 hours, and the flow rate of the inert gas is 10-30 ml / minute; the inert gas is nitrogen, argon or helium.

[0024] As a further preferred embodiment of the present technical solution, in step seven, the gas chromatograph uses a hydrogen flame ionization detector and a thermal conductivity detector connected in series for detection; and the gas sensor uses a combination of a metal oxide semiconductor sensor and an electrochemical sensor.

[0025] In order to solve the above technical problems, another technical solution adopted in the present application is: a hollow activated carbon supported catalyst deodorization system, comprising: a raw material processing module, a carbonization reaction module, an activation module, a catalyst preparation module, a loading module, a reaction control module and a detection and optimization module;

[0026] The raw material processing module is used to obtain carbonaceous raw materials, screen, clean and dry the obtained carbonaceous raw materials, and crush the processed raw materials;

[0027] The carbonization reaction module is used to carbonize the crushed carbonaceous raw material under the protection of inert gas to obtain a carbonized product; wherein the heating rate of the carbonization process is 3-8°C / min, the carbonization temperature is maintained at 450-550°C, the carbonization time is 1.5-2.5 hours, and the flow rate of the inert gas is 10-30 ml / min;

[0028] The activation module is used to activate the carbonization product by physical activation or chemical activation to form a hollow structure and pores to obtain hollow activated carbon with adsorption performance;

[0029] The catalyst preparation module is used to prepare single-component catalysts from two or more synergistic catalyst components, and mix them in a certain proportion to obtain a composite catalyst precursor; the catalyst components include a noble metal catalyst component and a transition metal oxide catalyst component; wherein the noble metal catalyst component is one or more of platinum, palladium, and rhodium, and the transition metal oxide catalyst component is one or more of copper oxide, manganese oxide, and iron oxide;

[0030] The loading module is used to load the composite catalyst precursor on the hollow activated carbon by an impregnation method, a coprecipitation method or a sol-gel method to obtain a hollow activated carbon loaded with the catalyst;

[0031] The reaction control module is used to fill the hollow activated carbon loaded with the catalyst into the reaction device, and accurately control the reaction temperature, reaction humidity and gas flow rate according to the source and concentration of the odorous gas, so that the odorous gas and the hollow activated carbon loaded with the catalyst are fully contacted and reacted;

[0032] The detection and optimization module is used to regularly detect the concentration of odorous substances in the gas after the reaction using a gas chromatograph or a gas sensor, record the removal rate data at different times, and optimize and adjust the reaction conditions and catalyst loading according to the detection results.

[0033] As a further preferred embodiment of the present technical solution, the system also includes a remote monitoring module, which is connected to the detection and optimization module and the reaction control module through a network, and is used to receive system operation data in real time and display it in the form of a visual chart on a remote terminal, while allowing the operator to remotely set system operation parameters and send control instructions.

[0034] As a further preferred embodiment of the present technical solution, when the load module adopts the immersion method, the immersion time is 3-6 hours, and the immersion process is accompanied by mechanical stirring, and the stirring speed is 50-150 rpm; when the load module adopts the co-precipitation method, the pH value of the precipitation reaction is controlled within the range of 7-10; when the load module adopts the sol-gel method, the sol formation time is 1-3 hours, and the gelation temperature is 60-80°C.

[0035] The embodiment of the present invention has the following advantages due to the adoption of the above technical solution:

[0036] 1. The present invention uses impregnation method, coprecipitation method and sol-gel method to make the composite catalyst and activated carbon more closely combined, effectively reducing the agglomeration or shedding phenomenon during use, thereby significantly improving the stability of catalytic activity and deodorization effect;

[0037] 2. The present invention uses physical activation and chemical activation to precisely control the specific surface area, pore structure and surface functional groups of activated carbon, creating a good foundation for catalyst loading. At the same time, it greatly enhances the adsorption capacity of activated carbon itself for odor, making up for the defect of insufficient performance of activated carbon.

[0038] 3. The present invention realizes the efficient integration of odor collection, treatment and emission links from carbon raw material treatment to final odor gas treatment through close collaboration of various modules, greatly improves the operating efficiency of the entire odor removal system, gives full play to the potential advantages of hollow activated carbon-loaded catalyst technology, and effectively meets people's urgent needs for efficient odor removal.

[0039] The present invention constructs multiple modules covering from raw material processing to detection optimization, and each module has a clear division of labor and close cooperation, from carbon raw material processing to final odor gas treatment, to achieve efficient integration of odor collection, treatment and emission. At the same time, the remote monitoring module can receive operation data in real time and support remote operation, which greatly improves the system operation efficiency, fully releases the potential of hollow activated carbon supported catalyst technology, meets the demand for efficient odor removal, and overcomes the shortcomings of the background technology in system integration application.

[0040] The above summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present invention will be readily apparent by reference to the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 It is a schematic diagram of the process of removing odor by hollow activated carbon supported catalyst of the present invention;

[0043] Figure 2 This is a schematic diagram of the functional modules of the hollow activated carbon-loaded catalyst deodorization system of the present invention. DETAILED DESCRIPTION

[0044] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0045] It should be clear that the following embodiments of the present disclosure are described by specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. The present disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that the following embodiments and features in the embodiments can be combined with each other in the absence of conflict. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0046] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein may be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present disclosure, it should be understood by those skilled in the art that an aspect described herein may be implemented independently of any other aspect, and two or more of these aspects may be combined in various ways. For example, any number of aspects described herein may be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein may be used to implement this device and / or practice this method.

[0047] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present disclosure. The drawings only show components related to the present disclosure rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0048] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0049] Figure 1 Schematic diagram of the process of removing odor by hollow activated carbon supported catalyst according to an embodiment of the present invention. It should be noted that if there are substantially the same results, the method of the present application is not limited to Figure 1 The process sequence shown is limited. Figure 1 As shown: A method for removing odors by hollow activated carbon supported catalyst comprises the following steps:

[0050] Step 1: obtaining a carbonaceous raw material, pre-treating the carbonaceous raw material, and crushing the pre-treated carbonaceous raw material;

[0051] Specifically, coconut shells, fruit shells, coal, etc. are first selected as carbonaceous raw materials. These raw materials are widely available and rich in carbon elements, and are the basic materials for preparing activated carbon;

[0052] Then, the carbonaceous raw materials are pretreated, including screening to remove impurities and parts that do not meet the particle size requirements to ensure the purity and uniformity of the raw materials; cleaning to wash away dust, soil and other pollutants on the surface of the raw materials; drying to remove moisture to provide a suitable raw material state for subsequent processing and prevent adverse effects caused by moisture during high-temperature treatment, such as affecting the carbonization effect or causing equipment corrosion, etc.

[0053] Finally, the pretreated carbonaceous raw materials are crushed into smaller particles to increase the specific surface area of ​​the raw materials, so that they can react more fully in the subsequent carbonization and activation process, thereby improving the production efficiency and quality of activated carbon; wherein, crushing the pretreated carbonaceous raw materials into smaller particles includes two steps: coarse crushing and fine crushing:

[0054] Coarse crushing: Use a jaw crusher to coarsely crush the dried carbonaceous raw materials. The jaw crusher squeezes and crushes the raw materials through the relative movement of two jaw plates. The jaw plate spacing and crushing frequency of the jaw crusher are adjusted according to the hardness of the raw materials and the required crushing particle size; for example, for coconut shells, the jaw plate spacing can be adjusted to 1-2 cm to initially crush the raw materials into smaller pieces;

[0055] Fine grinding: Use a ball mill to finely grind the coarsely crushed raw materials. The ball mill is equipped with grinding media (such as steel balls). During the rotation process, the grinding media impacts and grinds the raw materials to further refine the raw materials. The speed and grinding time of the ball mill are controlled to achieve the required particle size requirements; generally speaking, after grinding in a ball mill, the particle size of the carbonaceous raw materials can reach 80-120 meshes, which meets the subsequent carbonization and activation process requirements.

[0056] Step 2: Put the crushed carbonaceous raw material into a carbonization furnace and perform carbonization under the protection of inert gas to gradually decompose the organic matter in the carbonaceous raw material to form a carbon structure. After the carbonization is completed, a carbonized product is obtained;

[0057] Specifically, first, these crushed raw materials are placed in a carbonization furnace, which is a device specially designed for high-temperature treatment of raw materials. It can provide a stable high-temperature environment and control important parameters such as temperature and gas flow;

[0058] Then, it is very critical to choose an inert gas (such as nitrogen, argon or helium) for protection. This is because at high temperatures, if there is oxygen, the carbonaceous raw material will undergo a combustion reaction instead of the carbonization process we expect. Oxygen will cause the raw material to burn quickly, generate a lot of heat and exhaust gas, and destroy the structure of the raw material, and cannot form the desired carbon structure. The use of inert gas can exclude oxygen and form a relatively stable and safe reaction environment to ensure that the carbonization reaction can proceed in the expected direction; when the carbonization furnace is heated, under high temperature conditions, the organic matter in the carbonaceous raw material begins to undergo a series of complex chemical decomposition reactions. For example, hydrogen, oxygen, nitrogen and other elements in the raw material will be gradually removed from the raw material in the form of various small molecular compounds (such as hydrogen, water vapor, carbon dioxide, ammonia, etc.). The decomposition of these organic substances is a gradual process. As the temperature rises and time passes, the chemical bonds in the organic matter are constantly broken, and at the same time, more stable bonds begin to form between carbon elements, thereby forming a carbon structure rich in carbon elements;

[0059] Finally, after completing the predetermined carbonization time and reaching the required temperature conditions, a carbonization product is obtained. This product is a preliminary carbon material. The carbonization product already has the basic carbon skeleton of activated carbon, but it still needs subsequent treatment to increase its porosity and activity to improve its adsorption and catalytic ability for odorous gases.

[0060] Step 3: Activating the carbonized product by physical activation or chemical activation to form a hollow structure and pores to obtain hollow activated carbon with adsorption performance;

[0061] Among them, physical activation usually uses water vapor or carbon dioxide gas as an activator. These gases have certain chemical activity and can react with carbonization products under high temperature conditions. Some carbon atoms in the carbonization products will be gasified and removed, leaving vacancies in the original structure, thereby forming pores. As the reaction continues, more and more pores will be formed, and these pores will continue to expand and connect, eventually forming activated carbon with a rich pore structure; at the same time, the carbon atoms at different positions have different degrees of contact with the activator. In the continuous reaction process, pores of different sizes and shapes will eventually be produced, including micropores, mesopores and macropores. The presence of these pores greatly increases the specific surface area of ​​the activated carbon, thereby enhancing its adsorption performance;

[0062] Commonly used activators for chemical activation include potassium hydroxide, sodium hydroxide and other chemical reagents. These chemical reagents are highly corrosive and chemically active and can react chemically with carbonized products at relatively low temperatures. For example, when potassium hydroxide is used, a complex chemical reaction will occur to generate some potassium compounds and etch away some carbon atoms to generate pores. In this process, not only pores will be generated, but also the surface chemical properties of activated carbon can be adjusted to a certain extent to form functional groups that are conducive to adsorption. Due to the uneven penetration and reaction of chemical activators inside the structure of carbonized products, pores of different sizes and shapes will be formed in the carbonized products. The formation process of these pores may lead to the consumption of local carbonized products, thereby forming a hollow structure. Chemical activation can more accurately control the formation and distribution of pores. By selecting the type and amount of activators, the microstructure of activated carbon can be regulated to a certain extent, and finally a hollow activated carbon with adsorption properties is formed.

[0063] Whether it is physical activation or chemical activation, the ultimate goal is to obtain a hollow activated carbon with adsorption properties. This activated carbon has a high specific surface area and rich pore structure, and can adsorb odorous gases through physical adsorption and chemical adsorption. Physical adsorption is based on the van der Waals force between molecules, which makes the odorous gas molecules adhere to the pore surface of the activated carbon; chemical adsorption is through the chemical reaction between the functional groups on the surface of the activated carbon and the odorous gas molecules, fixing them on the activated carbon. The hollow activated carbon obtained through the activation process has greatly improved its adsorption performance, which can be better used in the fields of odor removal and gas purification, and provides an ideal carrier for subsequent catalyst loading operations.

[0064] Step 4: obtaining two or more catalyst components having synergistic effects, preparing single-component catalysts respectively, and mixing them in a certain proportion to obtain a composite catalyst precursor;

[0065] Among them, the catalyst components with synergistic effects usually select precious metal catalyst components (such as one or more of platinum, palladium, and rhodium) and transition metal oxide catalyst components (such as one or more of copper oxide, manganese oxide, and iron oxide); precious metal catalysts have high catalytic activity and chemical stability, and can show excellent catalytic performance in many chemical reactions, but their cost is relatively high; transition metal oxide catalysts are relatively low in cost and also have unique catalytic performance in certain specific reactions;

[0066] These two or more components are selected because they can play a synergistic role, that is, different catalyst components cooperate with each other in the catalytic process to improve the overall catalytic effect; for example, noble metals can promote certain key reaction steps, while transition metal oxides can assist in regulating the generation and conversion of reaction intermediates. The combination of the two can improve catalytic activity while reducing dependence on noble metals and reducing costs;

[0067] For precious metal catalysts, a common preparation method is an impregnation method; a solution containing a precious metal salt (such as chloroplatinic acid, palladium chloride, etc.) is impregnated on a suitable carrier (such as alumina, silica, etc.), and then the precious metal ions are reduced to a metallic state through a reduction process. For example, hydrogen is used as a reducing agent, and the carrier impregnated with the precious metal salt is subjected to a reduction reaction at a certain temperature and pressure, so that the precious metal ions are converted into metal atoms with catalytic activity and loaded on the carrier; another method is a chemical deposition method, which utilizes a chemical reaction to deposit the precious metal on the surface of the carrier under specific reaction conditions. By controlling the reaction conditions, the particle size and dispersion of the precious metal can be controlled, thereby optimizing its catalytic performance;

[0068] For transition metal oxide catalysts, a precipitation method can be used; a salt solution containing corresponding metal ions (such as copper sulfate, manganese sulfate, etc.) is mixed with a precipitant (such as sodium carbonate, sodium hydroxide, etc.), and the metal ions are precipitated in the form of hydroxides at an appropriate pH value and temperature, and then the hydroxides are converted into corresponding oxides through a calcination process; a sol-gel method can also be used, in which a metal salt is dissolved in a solvent, a suitable complexing agent or hydrolyzing agent is added, the metal ions are hydrolyzed to form a sol, and then a transition metal oxide with a specific crystal form and structure is formed through steps such as gelation, drying and calcination;

[0069] According to the required catalytic performance and target reaction, the mixing ratio of different single-component catalysts is determined through experiments and theoretical calculations. The determination of this ratio needs to consider many factors, including the catalytic activity and stability of different components and the synergistic effect between them. For example, if the goal is to catalyze the oxidation reaction of a complex odorous substance, more precious metal catalysts may be needed to start the key oxidation step, and an appropriate amount of transition metal oxide catalysts may be added to promote the conversion of intermediate products and stabilize the reaction system. After the single-component catalysts are prepared separately, they are physically mixed in a determined ratio. This mixing process needs to ensure uniformity to avoid excessive or low local catalyst concentrations that affect the final catalytic effect. Mechanical stirring, ball milling and other physical means can be used to fully mix the catalysts of different components to form a composite catalyst precursor. This precursor contains various catalyst components to prepare for subsequent loading on activated carbon, and due to the synergistic effect of the components, it is expected to exhibit better catalytic performance after loading to cope with complex odorous substance removal reactions.

[0070] Step 5: loading the composite catalyst precursor on the hollow activated carbon by an impregnation method, a coprecipitation method or a sol-gel method to obtain a hollow activated carbon loaded with the catalyst;

[0071] Among them, the impregnation method is to immerse the hollow activated carbon in a solution containing a composite catalyst precursor. By utilizing the porosity of the hollow activated carbon, the composite catalyst precursor in the solution will diffuse and adsorb to the surface and pores of the activated carbon driven by the concentration difference. The pores of the activated carbon are like small containers. The precursor molecules will enter these pores and attach to the pore walls. Since the pores have a high specific surface area, they can provide a large number of adsorption sites, so that the precursor can be fully dispersed on the activated carbon.

[0072] The co-precipitation method uses chemical reactions to precipitate the composite catalyst precursor on the surface and pores of hollow activated carbon. In a mixed system containing the precursor and hollow activated carbon, the chemical conditions of the solution (such as pH value) are adjusted to cause the precursor to undergo a precipitation reaction. The presence of activated carbon provides a large number of nucleation sites for precipitation, so that precipitation occurs preferentially on the surface and pores of activated carbon, thereby achieving the loading of the precursor.

[0073] The sol-gel method is to first dissolve the composite catalyst precursor in a solvent to form a sol. In the sol state, the precursor exists in the form of nanoscale particles or molecular clusters, which can be evenly dispersed in the solution. When the hollow activated carbon is added to the sol, as the solvent evaporates and the chemical reaction proceeds, the sol will gel on the surface and in the pores of the activated carbon. During the gelation process, the precursor is wrapped in the gel network, thereby achieving the loading of the precursor on the activated carbon.

[0074] Step 6: Fill the hollow activated carbon loaded with the catalyst into the reaction device, and control the reaction temperature, reaction humidity and gas flow rate according to the source and concentration of the odorous gas, so that the odorous gas and the hollow activated carbon loaded with the catalyst can fully contact and react;

[0075] Specifically, the hollow activated carbon loaded with the catalyst is carefully filled into a specially designed reaction device. The reaction device usually has good sealing and gas flowability to ensure that the odorous gas can pass through the activated carbon bed smoothly and prevent gas leakage. The filling process needs to ensure that the activated carbon is evenly distributed to avoid local accumulation or excessive gaps to ensure that the odorous gas can fully contact with the activated carbon when passing through. The composition and concentration of different odorous gases vary greatly. For example, the odor generated by indoor decoration may mainly contain volatile organic compounds (VOCs) such as formaldehyde and benzene, which have relatively low concentrations but are more harmful. The odorous gases in industrial waste gas may include hydrogen sulfide, ammonia, etc., which may have high concentrations and complex compositions. Therefore, the source and concentration of the odorous gas need to be accurately analyzed before treatment. The composition and concentration of the odorous gas are measured by professional gas detection equipment (such as gas chromatography-mass spectrometry, etc.), and the approximate range of the reaction conditions is preliminarily determined based on this information.

[0076] First, the reaction temperature has a key influence on the adsorption and catalytic reaction of odorous gases. For most catalytic oxidation reactions, increasing the temperature can usually speed up the reaction rate, but too high a temperature may cause catalyst deactivation or damage to the activated carbon structure. For example, for some common VOCs catalytic oxidation reactions, the appropriate temperature range may be between 200-400°C; when the concentration of odorous gases is high, the reaction temperature may need to be appropriately increased to ensure sufficient reaction rate; while for lower concentrations, lower temperatures may be sufficient to maintain effective reactions; at the same time, the active temperature window of the catalyst also needs to be considered to ensure that the temperature is within the range where the catalyst can function efficiently;

[0077] Then, humidity will also affect the reaction process. Within a certain range, an appropriate amount of water can promote certain catalytic reactions. For example, in some reactions using transition metal oxides as catalysts, water molecules can participate in the reaction process and promote the adsorption and activation of reactants. However, too high humidity may occupy the pores of activated carbon, hinder the adsorption of odorous gases, or cause the catalyst surface to be covered with water, reducing catalytic activity. For different odorous gases and catalyst systems, the optimal humidity range needs to be determined through experiments. Generally speaking, a relative humidity between 40% and 60% may be more appropriate, but the specific value needs to be adjusted according to actual conditions.

[0078] In addition, the gas flow rate determines the residence time of odorous gases in the activated carbon bed. If the flow rate is too fast, the odorous gases may leave the reaction device before they have enough time to fully contact with the activated carbon and catalyst, resulting in incomplete reaction; while too slow a flow rate will reduce the treatment efficiency and increase the equipment cost. The appropriate gas flow rate needs to be determined based on factors such as the size of the reaction device, the filling amount of activated carbon, and the concentration of odorous gases. For example, for small indoor air purification devices, the gas flow rate may be relatively low, generally between a few centimeters and tens of centimeters per second; and for large industrial waste gas treatment equipment, the gas flow rate may reach several meters per second, but reasonable design is needed to ensure that the gas has sufficient residence time and sufficient mixing in the reaction device.

[0079] Step 7: Use a gas chromatograph or a gas sensor to regularly detect the concentration of odorous substances in the gas after the reaction, record the removal rate data at different times, and optimize and adjust the reaction conditions and catalyst loading according to the detection results;

[0080] The calculation formula of the removal rate is: Removal rate = (initial odor substance concentration - odor substance concentration after reaction) / initial odor substance concentration × 100%;

[0081] After testing the post-reaction gas at different time points, the corresponding removal rate is calculated according to the above formula and recorded. This will form a time-removal rate data set. By analyzing these data, we can understand the changing trend of the odor removal effect over time. For example, if it is found that the removal rate gradually decreases over time, it may mean that the catalyst activity is reduced or the activated carbon adsorption is saturated. If it is detected that the removal rate of odorous substances is not ideal, first consider adjusting the reaction conditions. If it is found that the reaction temperature is too low, resulting in a slow reaction rate, the reaction temperature can be appropriately increased, but it should be noted that it should not exceed the catalyst's tolerance temperature range. If the humidity is not appropriate and affects the reaction, the humidity conditions can be optimized by adjusting the humidity of the intake air or adding dehumidification or humidification equipment in the reaction device. For the gas flow rate, if the flow rate is too fast, the odorous substances will be reduced. If the odor gas is not in sufficient contact, the flow rate can be reduced; conversely, if the flow rate is too slow and affects the treatment efficiency, the flow rate should be appropriately increased; when it is found that the removal rate continues to decline and the reaction conditions adjustment effect is not good, there may be a problem with the catalyst loading. For example, if the catalyst agglomerates or falls off on the activated carbon, it will lead to a reduction in catalytic active sites and affect the reaction effect. At this time, it is necessary to check whether the loading method is appropriate, such as whether the impregnation time and stirring speed in the impregnation method are appropriate, whether the pH value of the precipitation reaction in the co-precipitation method is accurately controlled, and whether the formation time of the sol and the gelation temperature in the sol-gel method are appropriate. If the catalytic effect is not good due to insufficient loading, you can consider re-preparing the hollow activated carbon loaded with the catalyst to increase the loading amount of the catalyst, but also pay attention to avoid excessive loading that affects the pore structure and gas diffusion performance of the activated carbon.

[0082] In one embodiment, specifically, in step three, physical activation is performed by using water vapor or carbon dioxide gas as an activator to react with the carbonized product at high temperature, so that the gas molecules erode the carbon structure to form pores of various sizes, thereby obtaining hollow activated carbon with adsorption properties; specifically, when water vapor or carbon dioxide gas is used as an activator, the gas molecules have higher energy under high temperature conditions (usually the temperature range is around 800-1000°C); taking water vapor as an example, water molecules react with carbon atoms in the carbonized product as follows: C+H2O→H2+CO, during this reaction, carbon atoms are oxidized to carbon monoxide gas and leave the carbon structure, and hydrogen also escapes; the reaction of carbon dioxide with carbon is similar: C+CO2→2CO, and these reactions continue on the surface and inside of the carbonized product. As the carbon atoms in some areas of the carbon structure are consumed first, the gas molecules continuously erode the carbon structure. As the reaction occurs randomly at different positions of the carbon structure and the reaction rates vary, the carbon atoms in some areas of the carbon structure are consumed first. As the reaction proceeds, the originally tightly arranged carbon structure gradually forms voids, which continue to expand and connect, thus forming a pore network of various sizes, from micropores (less than 2nm in diameter) to mesopores (2-50nm in diameter) and even macropores (greater than 50nm in diameter). This pore structure greatly increases the specific surface area of ​​the activated carbon, enabling it to adsorb more odor molecules and thus possess good adsorption performance. At the same time, in some cases, the internal reaction may be more intense, resulting in larger voids inside the carbon structure, thereby forming a hollow structure, which further increases the adsorption capacity and mass transfer efficiency of the activated carbon.

[0083] Chemical activation uses chemical reagents to react with carbonization products at high temperatures, etching the carbon structure to form pores of various sizes, thereby obtaining hollow activated carbon with adsorption properties. Specifically, chemical reagents commonly used in chemical activation include strong bases such as potassium hydroxide (KOH) and sodium hydroxide (NaOH). Taking KOH as an example, at high temperatures (generally 600-800°C), KOH will undergo a series of complex chemical reactions with carbonization products. First, KOH will penetrate into the pores and internal structure of the carbonized product, and then react with carbon atoms, such as: 4KOH+C→K2CO3+K2O+2H2. In this process, the carbon atoms in the carbon structure are etched away to form pores. At the same time, the generated potassium salt can be removed in the subsequent treatment process (such as washing, calcination, etc.), further optimizing the pore structure. Chemical activation can not only form pores, but also regulate the surface functional groups of activated carbon to a certain extent. During the reaction, some oxygen-containing functional groups (such as hydroxyl, carboxyl, etc.) will be introduced on the surface of activated carbon. These functional groups can enhance the chemical adsorption ability of activated carbon for certain odor molecules and further improve its adsorption performance. Compared with physical activation, chemical activation can more accurately control the size, distribution and surface chemical properties of the pores. By selecting different chemical reagents and reaction conditions, hollow activated carbon with specific properties can be prepared to meet the needs of different odor treatment scenarios.

[0084] In one embodiment, specifically, in step five, the impregnation method is performed by immersing the hollow activated carbon in a solution containing a catalyst precursor, so that the catalyst precursor is adsorbed on the activated carbon, and then drying and calcining are performed to obtain a hollow activated carbon loaded with a catalyst; the specific steps of the impregnation method are as follows:

[0085] First, the composite catalyst precursor is dissolved in a suitable solvent (such as water, an organic solvent, etc.) to form a uniform solution;

[0086] Then, the hollow activated carbon is added to the solution and soaked for a period of time, which generally ranges from several hours to more than ten hours. The specific time depends on the type of precursor and the properties of the activated carbon. For example, the soaking time may be 3-6 hours.

[0087] During the soaking process, mechanical stirring can be used to promote uniform adsorption of the precursor. The stirring speed is usually controlled within a certain range, such as 50-150 rpm, to ensure that the precursor in the solution is in uniform contact with the activated carbon and prevent local concentrations from being too high or too low.

[0088] Afterwards, the impregnated activated carbon is taken out and dried (generally oven drying is used to evaporate the solvent at a certain temperature) to fix the precursor on the activated carbon;

[0089] Finally, a calcination operation is performed, which is usually carried out at a high temperature. The purpose is to convert the precursor into an active catalyst. During the calcination process, the precursor undergoes decomposition, oxidation-reduction and other reactions to generate the final desired catalyst and firmly load it on the activated carbon to obtain a hollow activated carbon loaded with the catalyst.

[0090] The co-precipitation method is to add the hollow activated carbon and the catalyst precursor to the precipitant solution at the same time, so that the catalyst precursor is precipitated on the surface and pores of the activated carbon, and then dried and calcined to obtain the hollow activated carbon loaded with the catalyst; the specific steps of the co-precipitation method are as follows:

[0091] Firstly, the hollow activated carbon and the composite catalyst precursor are simultaneously added into a solution containing a precipitant;

[0092] Then, the pH value of the solution is adjusted. Generally, the pH value is controlled within a certain range, such as 7-10, to initiate the precipitation reaction of the precursor. Different precursors may require different pH ranges to ensure the smooth progress of the precipitation reaction.

[0093] During the precipitation process, the precursor forms precipitates on the surface and in the pores of the activated carbon. Due to the adsorption and nucleation of the activated carbon, the precipitates will preferentially grow on its surface and in its pores;

[0094] Subsequently, the product is filtered and washed to remove excess precipitant and impurities;

[0095] Finally, after drying and calcination, similar to the impregnation method, the precipitate is converted into an active catalyst, thereby obtaining a catalyst-loaded hollow activated carbon.

[0096] The sol-gel method dissolves the catalyst precursor in a solvent to form a sol, then adds the hollow activated carbon into the sol to gel the sol on the surface and pores of the activated carbon, and then obtains the hollow activated carbon loaded with the catalyst after drying and calcination. The specific steps of the sol-gel method are as follows:

[0097] First, the composite catalyst precursor is dissolved in a solvent, and a proper amount of acid or alkali additives are added to initiate hydrolysis and polycondensation of the precursor to form a sol. The formation time of the sol may take 1-3 hours to ensure that the precursor is fully hydrolyzed and polycondensed;

[0098] Then, the hollow activated carbon is added to the sol and stirred evenly to allow the sol to enter the pores of the activated carbon;

[0099] Place the system under certain temperature conditions (e.g. 60-80°C) to promote sol gelation;

[0100] After gelation is completed, it is dried to remove the solvent and water, making the gel network more stable;

[0101] Finally, calcination is performed to convert the precursor in the gel into an active catalyst, and finally a hollow activated carbon loaded with the catalyst is obtained.

[0102] In one embodiment, specifically, in step 4, the synergistic catalyst components include a noble metal catalyst component and a transition metal oxide catalyst component, wherein the noble metal catalyst component is one or more of platinum, palladium, and rhodium, and the transition metal oxide catalyst component is one or more of copper oxide, manganese oxide, and iron oxide; wherein platinum (Pt), palladium (Pd), rhodium (Rh) and other noble metals as catalyst components have high activity and good selectivity, because they have unique electronic structures and surface chemical properties, these noble metal atoms can adsorb reactant molecules and activate them, reduce the activation energy of the reaction, and promote the occurrence of the reaction. For example, in many redox reactions, noble metals can adsorb oxygen molecules and dissociate them into active oxygen species (such as O, O2 - These active oxygen species can react with odorous substances and convert them into harmless products. Precious metal catalysts have high activity but relatively high cost. Therefore, they are usually used in combination with other catalyst components in practical applications to improve their performance and reduce costs.

[0103] Transition metal oxides such as copper oxide (CuO), manganese oxide (MnO2), and iron oxide (Fe2O3) also have certain catalytic activity as catalyst components. They can provide multiple oxidation states, participate in the electron transfer process, and play a role in transferring electrons in the reaction. For example, in some catalytic oxidation reactions, transition metal oxides can transfer electrons to reactant molecules to activate them and thus participate in the reaction. The cost of transition metal oxides is relatively low, and their structure and properties can be regulated by changing the preparation conditions (such as synthesis method, precursor, calcination temperature, etc.), which provides more flexibility for the design of catalysts.

[0104] When the precious metal catalyst component and the transition metal oxide catalyst component are used together, a synergistic effect can be produced; the precious metal can serve as an active center to promote the occurrence of key reaction steps; and the transition metal oxide can assist the precious metal catalyst to promote the adsorption and activation of the reactants and the desorption of the products. For example, the transition metal oxide can enrich the reactant molecules on the catalyst surface, making it easier for them to contact with the precious metal active centers, thereby increasing the reaction rate. At the same time, the transition metal oxide can also adjust the selectivity of the reaction and avoid the occurrence of some side reactions.

[0105] In one embodiment, specifically, in step 1, the carbonaceous raw material includes coconut shell, fruit shell, and coal;

[0106] Among them, coconut shell is a high-quality carbon raw material with a relatively high carbon content and a relatively regular fiber structure. This structure is conducive to the formation of abundant pores in the subsequent carbonization and activation process, and its own impurity content is relatively low, which can be used to prepare activated carbon with good performance. For example, components such as lignin and cellulose in coconut shell can be effectively converted into carbon structure under high temperature treatment, providing a basis for the formation of activated carbon.

[0107] Fruit shells are similar to coconut shells, containing a certain amount of lignin and cellulose, and have a certain hardness and porosity. During the carbonization process, the decomposition and reorganization of these components can produce a porous structure. In addition, it has a wide range of sources and relatively low costs, making it an economical choice of carbon raw materials.

[0108] Coal is a traditional carbonaceous raw material with abundant reserves. Different types of coal (such as anthracite, bituminous coal, etc.) differ in carbon content and impurity composition, but in general, activated carbon can be prepared through appropriate treatment methods. The carbon in coal can form a carbon skeleton at high temperature, but it may contain more impurities such as ash, which need to be removed or controlled in subsequent processing.

[0109] Pre-treatment of carbonaceous raw materials includes screening, cleaning and drying;

[0110] Among them, screening treatment: large particle impurities (such as stones, metal fragments, etc.) and parts that do not meet the particle size requirements in the carbonaceous raw materials can be removed through screening. For example, the raw materials are screened using screens of different apertures to ensure that the raw materials entering the subsequent processing links have a uniform particle size, which is conducive to the uniformity of subsequent carbonization and activation reactions. If the raw material particle size difference is too large, local incomplete reaction or overreaction may occur during the carbonization process;

[0111] Cleaning treatment: The purpose of cleaning is to remove dust, dirt, microorganisms and other pollutants on the surface of the raw materials. These pollutants may have adverse effects in the subsequent high-temperature treatment process, such as increasing the ash content and affecting the formation of pore structure. Water washing can be used to soak the raw materials in water, stir and filter, and repeat several times until the cleaning water is clear;

[0112] Drying treatment: Drying is to remove moisture from the raw materials. Moisture will consume heat during the carbonization process and may cause the raw materials to crack during heating or affect the carbonization reaction. Usually, natural drying or oven drying at a certain temperature is used to reduce the moisture content of the raw materials to an appropriate level. Generally, the moisture content is required to be within a certain range (such as less than 10%) to ensure the stability and efficiency of the carbonization process.

[0113] In one embodiment, specifically, in step 2, carbonization is performed under the protection of an inert gas, wherein the heating rate of the carbonization process is 3-8°C / min, the carbonization temperature is maintained at 450-550°C, the carbonization time is 1.5-2.5 hours, and the flow rate of the inert gas is 10-30 ml / min;

[0114] The heating rate is controlled at 3-8°C / min to ensure that the carbonaceous raw material can be heated evenly. If the heating rate is too fast, the outside of the raw material may heat up quickly and react, while the inside has not yet reached the reaction temperature, which will lead to uneven reaction and affect the quality and performance of the carbonized product. For example, the pore structure of the carbonized product may be uneven, some areas may be over-carbonized and other areas may be under-carbonized. On the contrary, if the heating rate is too slow, the production efficiency will be reduced and the production cost will be increased.

[0115] The carbonization temperature is kept at 450-550℃, which is the range obtained through a large number of experimental optimizations. In this temperature range, the organic matter in the carbonaceous raw materials can be fully decomposed to form a stable carbon structure. If the temperature is too low, the organic matter will not be completely decomposed, and sufficient carbon structure cannot be formed, which will affect the performance of subsequent activated carbon. If the temperature is too high, it may cause sintering or collapse of the carbon structure, reduce porosity, and is also not conducive to the preparation of activated carbon.

[0116] The carbonization time is set to 1.5-2.5 hours to ensure that the organic matter has enough time to complete the decomposition reaction. If the time is too short, the organic matter will not be fully decomposed; if the time is too long, continued heating after a stable carbon structure has been formed may cause unnecessary side reactions and reduce the quality of the carbonized product.

[0117] The inert gas flow rate is set within the range of 10-30 ml / min, which can effectively maintain the inert atmosphere in the carbonization furnace. Sufficient inert gas flow can timely remove a small amount of oxygen that may leak in, prevent the carbonaceous raw materials from reacting with oxygen to ensure the safety and stability of the carbonization process. If the flow rate is too small, oxygen cannot be effectively removed, which will increase the risk of combustion; if the flow rate is too large, it will cause gas waste, increase production costs, and may interfere with the temperature field and airflow field in the furnace, affecting the uniformity of the carbonization reaction;

[0118] The inert gas is nitrogen, argon or helium; among them, nitrogen, argon or helium are selected as inert gases because of their stable chemical properties and are not easy to react chemically with carbonaceous raw materials; nitrogen is the most commonly used because of its relatively low cost and easy acquisition; argon and helium are more chemically inert, but relatively expensive, and may be used in some cases where more stringent requirements are placed on the reaction environment.

[0119] In one embodiment, specifically, in step seven, the gas chromatograph uses a hydrogen flame ionization detector (FID) and a thermal conductivity detector (TCD) connected in series for detection;

[0120] Among them, FID has a highly sensitive detection capability for organic compounds. Its working principle is that when organic odor substances enter the FID detector, they undergo an ionization reaction under the high temperature of the hydrogen flame, and the generated ion flow is collected and converted into an electrical signal. Since different organic odor substances have different ionization efficiencies and generated ion flow intensities in the FID, the concentration of organic odor substances can be determined by detecting the intensity of the ion flow signal. For example, for common volatile organic compounds (VOCs) such as formaldehyde, benzene, toluene, etc., FID can accurately detect the changes in their content in the gas after the reaction, providing important data for evaluating the deodorization effect.

[0121] TCD is mainly used to detect inorganic gases and some low molecular weight organic gases. It is based on the characteristic that different gases have different thermal conductivities. When the gas passes through the thermal conductivity cell, it will cause the resistance of the thermistor in the thermal conductivity cell to change, thereby generating an electrical signal. By measuring the size of the electrical signal, the concentration of the gas can be determined. In the process of odorous gas treatment, there may be some inorganic odorous gases such as hydrogen sulfide and ammonia. TCD can effectively detect the residual situation of these gases, complementing FID to achieve comprehensive detection of gas components after the reaction.

[0122] Using F ID and TCD in series can give full play to the advantages of both, broaden the detection range, and improve the accuracy and reliability of detection. In one detection process, both organic and inorganic odor substances can be analyzed at the same time, avoiding the problem of missing some odor substances that may be caused by using a single detector, so as to more comprehensively understand the treatment effect of the odor removal system on different types of odor substances;

[0123] The gas sensor uses a combination of metal oxide semiconductor sensor and electrochemical sensor;

[0124] Among them, when the metal oxide semiconductor sensor is working, when the odor gas molecules are adsorbed on its surface, it will cause the electrical properties of the sensor to change, such as the change of resistance value. Different odor gases have different effects on the sensor. By detecting the change of this electrical property, and after pre-calibration and data analysis, the concentration of the odor gas can be determined. The metal oxide semiconductor sensor has the advantages of fast response speed and relatively low cost. It has a good detection effect on some common odor gases such as ethanol and acetone.

[0125] Electrochemical sensors use electrochemical reactions to detect odorous gases. Odorous gases undergo oxidation or reduction reactions on the electrode surface of the sensor. The resulting current or potential changes have a certain functional relationship with the gas concentration. Electrochemical sensors have high selectivity and sensitivity to certain specific gases. For example, they have good detection effects on gases such as carbon monoxide and sulfur dioxide.

[0126] The combination of metal oxide semiconductor sensors and electrochemical sensors can combine the advantages of both and improve the accuracy and reliability of odor gas detection. Different sensors have different response characteristics to different types of odor gases. The combined use can expand the detection range and more accurately monitor the concentration changes of odor substances in the gas after the reaction, providing strong support for the performance evaluation and optimization of the odor removal system.

[0127] In summary, the hollow activated carbon loaded catalyst deodorization method provided in this embodiment is to obtain hollow activated carbon by pretreating and crushing carbonaceous raw materials such as coconut shells, carbonizing under inert gas protection, and physically or chemically activating them, and then preparing a composite catalyst precursor containing precious metals and transition metal oxides and loading it on it, filling it into the reaction device, adjusting the reaction conditions according to the odor situation, and finally detecting and optimizing. Each link is closely connected, which significantly improves the catalytic activity and the stability of the deodorization effect, and makes up for the defect of insufficient performance of activated carbon.

[0128] Figure 2 Schematic diagram of the functional modules of the hollow activated carbon supported catalyst deodorization system of the embodiment of the present application. Figure 2 As shown, the hollow activated carbon loaded catalyst deodorization system includes: a raw material processing module, a carbonization reaction module, an activation module, a catalyst preparation module, a loading module, a reaction control module and a detection and optimization module;

[0129] A raw material processing module is used to obtain carbonaceous raw materials, screen, clean and dry the obtained carbonaceous raw materials, and crush the processed raw materials;

[0130] A carbonization reaction module is used to carbonize the crushed carbonaceous raw material under the protection of an inert gas to obtain a carbonized product; wherein the heating rate of the carbonization process is 3-8°C / min, the carbonization temperature is maintained at 450-550°C, the carbonization time is 1.5-2.5 hours, and the flow rate of the inert gas is 10-30 ml / min;

[0131] An activation module is used to activate the carbonization product by physical activation or chemical activation to form a hollow structure and pores to obtain a hollow activated carbon with adsorption performance;

[0132] The catalyst preparation module is used to prepare single-component catalysts from two or more synergistic catalyst components, and mix them in a certain proportion to obtain a composite catalyst precursor; the catalyst components include precious metal catalyst components and transition metal oxide catalyst components; the precious metal catalyst components are one or more of platinum, palladium, and rhodium, and the transition metal oxide catalyst components are one or more of copper oxide, manganese oxide, and iron oxide;

[0133] A loading module, used to load the composite catalyst precursor on the hollow activated carbon by an impregnation method, a coprecipitation method or a sol-gel method to obtain a hollow activated carbon loaded with the catalyst;

[0134] The reaction control module is used to fill the hollow activated carbon loaded with the catalyst into the reaction device, and accurately control the reaction temperature, reaction humidity and gas flow rate according to the source and concentration of the odorous gas, so that the odorous gas and the hollow activated carbon loaded with the catalyst can fully contact and react;

[0135] The detection and optimization module is used to regularly detect the concentration of odorous substances in the gas after the reaction using a gas chromatograph or a gas sensor, record the removal rate data at different times, and optimize and adjust the reaction conditions and catalyst loading according to the detection results.

[0136] In one embodiment, specifically, the system also includes a remote monitoring module, which connects the detection and optimization module and the reaction control module through a network, is used to receive system operation data in real time, and display it in the form of a visual chart on a remote terminal, while allowing the operator to remotely set system operation parameters and send control instructions.

[0137] In one embodiment, specifically, when the load module adopts the immersion method, the immersion time is 3-6 hours, and the immersion process is accompanied by mechanical stirring, and the stirring speed is 50-150 rpm; when the load module adopts the co-precipitation method, the pH value of the precipitation reaction is controlled within the range of 7-10; when the load module adopts the sol-gel method, the sol formation time is 1-3 hours, and the gelation temperature is 60-80°C.

[0138] In summary, the hollow activated carbon-loaded catalyst odor removal system provided in the embodiment of the present invention realizes the efficient integration of odor collection, treatment and emission links through the coordinated work of modules such as raw material processing, carbonization reaction, activation, catalyst preparation, loading, reaction control, and detection and optimization, greatly improves the operating efficiency of the entire odor removal system, gives full play to the potential advantages of hollow activated carbon-loaded catalyst technology, and effectively meets people's urgent needs for efficient odor removal.

[0139] For other details about the technical solutions implemented by each module in the above-mentioned embodiment system, please refer to the description of the hollow activated carbon-loaded catalyst deodorization method and its system in the above-mentioned embodiment, which will not be repeated here.

[0140] It should be noted that each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other. For system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0141] The basic principles of the present disclosure are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present disclosure are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present disclosure. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, and are not limitations. The above details do not limit the present disclosure to the necessity of adopting the above specific details to be implemented.

[0142] In the present disclosure, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. The block diagrams of the devices, devices, equipment, and systems involved in the present disclosure are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, devices, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0143] Additionally, as used herein, "or" used in a list of items beginning with "at least one" indicates a separate list, so that, for example, a list of "at least one of A, B, or C" means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Furthermore, the word "exemplary" does not mean that the example described is preferred or better than other examples.

[0144] It should also be noted that in the system and method of the present disclosure, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present disclosure.

[0145] Various changes, substitutions, and modifications of the techniques described herein may be made without departing from the teachings defined by the appended claims. Furthermore, the scope of the claims of the present disclosure is not limited to the specific aspects of the processes, machines, manufactures, compositions of events, means, methods, and actions described above. Currently existing or later to be developed processes, machines, manufactures, compositions of events, means, methods, or actions that perform substantially the same functions or achieve substantially the same results as the corresponding aspects described herein may be utilized. Thus, the appended claims include such processes, machines, manufactures, compositions of events, means, methods, or actions within their scope.

[0146] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present disclosure. Therefore, the present disclosure is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0147] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present disclosure to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A method for removing odor by using a hollow activated carbon supported catalyst, characterized in that: The following steps are involved: Step 1: obtaining a carbonaceous raw material, pre-treating the carbonaceous raw material, and crushing the pre-treated carbonaceous raw material; Step 2: Put the crushed carbonaceous raw material into a carbonization furnace and perform carbonization under the protection of inert gas to gradually decompose the organic matter in the carbonaceous raw material to form a carbon structure. After the carbonization is completed, a carbonized product is obtained; Step 3: Activate the carbonized product by physical activation or chemical activation to form a hollow structure and pores to obtain hollow activated carbon with adsorption performance; Step 4: obtaining two or more catalyst components having synergistic effects, preparing single-component catalysts respectively, and mixing them in a certain proportion to obtain a composite catalyst precursor; Step 5: loading the composite catalyst precursor on the hollow activated carbon by an impregnation method, a coprecipitation method or a sol-gel method to obtain a hollow activated carbon loaded with the catalyst; Step 6: Fill the hollow activated carbon loaded with the catalyst into the reaction device, and control the reaction temperature, reaction humidity and gas flow rate according to the source and concentration of the odorous gas, so that the odorous gas and the hollow activated carbon loaded with the catalyst can fully contact and react; Step 7: Use a gas chromatograph or a gas sensor to regularly detect the concentration of odorous substances in the gas after the reaction, record the removal rate data at different times, and optimize and adjust the reaction conditions and catalyst loading according to the test results.

2. The method for removing odor by using hollow activated carbon supported catalyst according to claim 1, characterized in that: In step three, the physical activation uses water vapor or carbon dioxide gas as an activator to react with the carbonization product at high temperature, so that the gas molecules erode the carbon structure to form pores of various sizes, thereby obtaining hollow activated carbon with adsorption performance; The chemical activation uses chemical reagents to react with carbonization products at high temperature to etch the carbon structure to form pores of various sizes, thereby obtaining hollow activated carbon with adsorption properties.

3. The method for removing odor by using hollow activated carbon supported catalyst according to claim 1, characterized in that: In step 5, the impregnation method is to immerse the hollow activated carbon in a solution containing a catalyst precursor so that the catalyst precursor is adsorbed on the activated carbon, and then dry and calcine to obtain a hollow activated carbon loaded with a catalyst; The co-precipitation method is to add the hollow activated carbon and the catalyst precursor to the precipitant solution at the same time, so that the catalyst precursor is precipitated on the surface and in the pores of the activated carbon, and then dried and calcined to obtain the hollow activated carbon loaded with the catalyst; The sol-gel method is to dissolve the catalyst precursor in a solvent to form a sol, then add the hollow activated carbon into the sol to gel the sol on the surface and pores of the activated carbon, and obtain the hollow activated carbon loaded with the catalyst after drying and calcination.

4. The method for removing odor by using hollow activated carbon supported catalyst according to claim 1, characterized in that: In step 4, the synergistic catalyst components include a noble metal catalyst component and a transition metal oxide catalyst component, wherein the noble metal catalyst component is one or more of platinum, palladium, and rhodium, and the transition metal oxide catalyst component is one or more of copper oxide, manganese oxide, and iron oxide.

5. The method for removing odor by using hollow activated carbon supported catalyst according to claim 1, characterized in that: In step one, the carbonaceous raw materials include coconut shells, fruit shells, and coal; the pretreatment of the carbonaceous raw materials includes screening, washing, and drying.

6. The method for removing odor by using hollow activated carbon supported catalyst according to claim 1, characterized in that: In step 2, carbonization is carried out under the protection of an inert gas, wherein the heating rate of the carbonization process is 3-8°C / min, the carbonization temperature is maintained at 450-550°C, the carbonization time is 1.5-2.5 hours, and the flow rate of the inert gas is 10-30 ml / min; the inert gas is nitrogen, argon or helium.

7. The method for removing odor by using hollow activated carbon supported catalyst according to claim 1, characterized in that: In step seven, the gas chromatograph uses a hydrogen flame ionization detector and a thermal conductivity detector connected in series for detection; the gas sensor uses a combination of a metal oxide semiconductor sensor and an electrochemical sensor.

8. A hollow activated carbon supported catalyst deodorization system, applied to the hollow activated carbon supported catalyst deodorization method according to any one of claims 1 to 7, characterized in that: include: Raw material processing module, carbonization reaction module, activation module, catalyst preparation module, loading module, reaction control module and detection and optimization module; The raw material processing module is used to obtain carbonaceous raw materials, screen, clean and dry the obtained carbonaceous raw materials, and crush the processed raw materials; The carbonization reaction module is used to carbonize the crushed carbonaceous raw material under the protection of inert gas to obtain a carbonized product; wherein the heating rate of the carbonization process is 3-8°C / min, the carbonization temperature is maintained at 450-550°C, the carbonization time is 1.5-2.5 hours, and the flow rate of the inert gas is 10-30 ml / min; The activation module is used to activate the carbonization product by physical activation or chemical activation to form a hollow structure and pores to obtain hollow activated carbon with adsorption performance; The catalyst preparation module is used to prepare single-component catalysts from two or more synergistic catalyst components, and mix them in a certain proportion to obtain a composite catalyst precursor; the catalyst components include a noble metal catalyst component and a transition metal oxide catalyst component; wherein the noble metal catalyst component is one or more of platinum, palladium, and rhodium, and the transition metal oxide catalyst component is one or more of copper oxide, manganese oxide, and iron oxide; The loading module is used to load the composite catalyst precursor on the hollow activated carbon by an impregnation method, a coprecipitation method or a sol-gel method to obtain the hollow activated carbon loaded with the catalyst; The reaction control module is used to fill the hollow activated carbon loaded with the catalyst into the reaction device, and accurately control the reaction temperature, reaction humidity and gas flow rate according to the source and concentration of the odorous gas, so that the odorous gas and the hollow activated carbon loaded with the catalyst are fully contacted and reacted; The detection and optimization module is used to regularly detect the concentration of odorous substances in the gas after the reaction using a gas chromatograph or a gas sensor, record the removal rate data at different times, and optimize and adjust the reaction conditions and catalyst loading according to the detection results.

9. The hollow activated carbon supported catalyst deodorization system according to claim 8, characterized in that: The system also includes a remote monitoring module, which is connected to the detection and optimization module and the reaction control module through a network, and is used to receive system operation data in real time and display it in the form of a visual chart on a remote terminal, while allowing operators to remotely set system operation parameters and send control instructions.

10. The hollow activated carbon supported catalyst deodorization system according to claim 8, characterized in that: When the load module adopts the impregnation method, the impregnation time is 3-6 hours, and the impregnation process is accompanied by mechanical stirring, and the stirring speed is 50-150 rpm; when the load module adopts the co-precipitation method, the pH value of the precipitation reaction is controlled within the range of 7-10; when the load module adopts the sol-gel method, the sol formation time is 1-3 hours, and the gelation temperature is 60-80°C.

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