A device for simultaneously removing tin dust exhaust gas and VOCs

Abstract

The application discloses a device for synchronously removing tin dust waste gas and VOCs, which comprises a device shell 1, a cylindrical filter layer 2, a dedusting layer 3, a VOCs degradation layer 4 and an outlet 5 on one side of the device shell arranged in the device shell from outside to inside in sequence, wherein the outlet 5 is communicated with the VOCs degradation layer 4, and the diameters of the outlet 5 and the VOCs degradation layer 4 are the same; the VOCs degradation layer 4 comprises a catalyst layer, a heating pipe and an ultraviolet lamp tube. The device can degrade VOCs by adopting adsorption, photocatalysis or thermal catalysis and other technologies while separating and recovering tin dust, so that tin recovery and VOCs removal are realized synchronously.

Description

Technical Field

[0001] This invention belongs to the field of solder fume resource recovery and treatment technology, and specifically relates to a filter bag for simultaneous tin recovery and VOC removal and its application method. Background Technology

[0002] In recent decades, the market demand for electronic products has expanded rapidly. The production processes of products such as cameras and circuit boards involve soldering, baking, and curing, generating a large amount of soldering waste gas. The main components of this waste gas are soldering fumes and volatile organic compounds (VOCs), and small amounts of HCl, H2S, and NH3 may also be present. Soldering fumes are generally very small particulate matter, originating from various soldering materials such as solder wire and solder paste used in reflow soldering, wave soldering, and manual soldering processes. VOCs mainly come from the baking and volatilization of circuit boards and the adhesives used. Solder dust and VOCs not only pollute the environment and harm human health, but also lead to resource waste.

[0003] For soldering exhaust gas, there are currently three main types of treatment technologies used by enterprises. The first type is ventilation, which is chosen by many small and medium-sized enterprises. However, this method cannot effectively purify the toxic and harmful components in soldering fumes and therefore does not comply with laws and regulations. The second type is single filtration or adsorption, which can only treat one of the solder dust or VOCs and cannot remove them all. The third type is combined technology, such as "filtration + adsorption + catalysis", which combines the three devices in series. This not only involves complex processes and large floor space, but also has high equipment investment and operating costs.

[0004] The development of simple, reliable, space-saving, and low-cost processes would be of great significance for the treatment of soldering fumes. Electrostatic precipitators and bag filters are commonly used for treating solder dust. Compared to electrostatic precipitators, bag filters offer advantages such as high dust removal efficiency, wide applicability, stable and reliable operation, and low cost. Using filter bags to separate and recover solder dust from soldering fumes is a conventional or easily conceived technique in this field, but it only removes dust and cannot remove VOCs and other waste gases. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, this invention provides a filter bag for simultaneous VOCs removal during tin recovery and its application method, thereby achieving simultaneous VOCs removal during tin dust recovery. The specific technical solution of this invention is as follows:

[0006] A device for simultaneously removing tin dust and VOCs from waste gas includes a housing 1, a cylindrical filter layer 2, a dust removal layer 3, a VOCs degradation layer 4 arranged sequentially from the outside to the inside of the housing, and an outlet 5 on one side of the housing. This design allows for pretreatment of organic waste gas containing dust and acidic / alkaline gases, filtering out the dust and absorbing or adsorbing away the acidic / alkaline gases, thus preventing these components from clogging or corroding / poisoning when passing through the VOCs degradation layer. Furthermore, the outlet 5 is connected to the VOCs degradation layer 4, and both have the same diameter; the VOCs degradation layer 4 includes a catalyst layer, a heating element, and an ultraviolet lamp.

[0007] Filter layer 2 selects different filter media according to the different temperatures of tin dust exhaust gas. When the temperature is below 250℃, polytetrafluoroethylene filter media with acid and alkali corrosion resistance, wear resistance and high temperature resistance is selected, with a pore size range of 0.08-3μm and a porosity greater than 85% is selected. When the temperature is above 250℃, 316L stainless steel fiber felt with corrosion resistance, wear resistance and ultra-high temperature resistance is selected, with a pore size range of 0.1-3μm is selected.

[0008] The impurity removal layer 3 is composed of two modified adsorbent materials. Both layers are based on high-temperature resistant activated carbon fiber felt. One layer undergoes sulfonation modification to adsorb and remove alkaline gases (NH3) from the waste gas, while the other layer undergoes basic copper carbonate loading modification to adsorb and remove acidic gases such as HCl and H2S. The sulfonation modification of the activated carbon fiber felt utilizes both concentrated sulfuric acid and a 10 mol / L cuprous sulfate solution as sulfonating agents, with a volume ratio of concentrated sulfuric acid to cuprous sulfate solution of 1:2. Sulfonation is first performed at 90℃ for 12 hours, followed by sulfonation at 140℃ for another 12 hours. The basic copper carbonate loading process for the activated carbon fiber felt involves impregnating the activated carbon fiber felt with a copper nitrate solution to enhance the Cu content. 2+ The copper nitrate is bonded to the functional groups on the surface of the activated carbon fiber felt, dried, and then impregnated with sodium carbonate solution to form basic copper carbonate on the surface of the activated carbon fiber felt. The molar ratio of copper nitrate to sodium carbonate used is 1:0.7.

[0009] VOCs degradation layer 4 selects different catalysts according to the different temperatures of tin dust exhaust gas. When the temperature is below 250℃, a photothermal synergistic catalyst is used, and when the temperature is above 250℃, a thermally activated catalyst is used. Preferably, the photothermal synergistic catalyst is prepared using a hydrothermal method combined with a stripping-reassembly method. First, titanate nanotubes are prepared using a hydrothermal method with tetrabutyl titanate and sodium hydroxide solution as raw materials, and then acid-washed to obtain titanate nanotubes. Next, the titanate nanotubes are soaked in ethylamine to obtain a titanate ion nanotube layer sol, and then a solution of chloroplatinic acid hexahydrate and cerium acetate is added dropwise. After precipitation, washing, and drying, a platinum-cerium binary titanate photothermal synergistic catalyst is obtained. The thermally activated catalyst is prepared using a hydrothermal method combined with a vacuum impregnation method. First, titanate nanotubes are prepared using a hydrothermal method with tetrabutyl titanate and sodium hydroxide solution as raw materials, and then acid-washed, water-washed, and dried to obtain titanate nanotubes. Next, the titanate nanotubes are vacuum impregnated with a solution of chloroplatinic acid hexahydrate and cerium acetate, and then dried and calcined to obtain a platinum-cerium-loaded TiO2 nanotube thermally activated catalyst.

[0010] Furthermore, the cleaning method of filter layer 2 is pulse cleaning; the filtered gas is monitored in real time, and when acidic or alkaline gases such as NH3, HCl and H2S are detected to exceed the standard, a new impurity removal layer is replaced in time, and the old impurity removal layer can be recycled after regeneration.

[0011] This invention achieves simultaneous treatment of tin dust waste gas, adsorption of acid and alkali waste gas impurities, and photo-thermal catalytic degradation of VOCs in a filtration layer, a purification layer, and a VOCs degradation layer. Simultaneously, concentrated sulfuric acid and cuprous sulfate are used to sulfonate-modify activated carbon fiber felt. The introduced sulfonic acid groups combine with ammonia gas through electrophilic substitution, and the introduced cuprous ions adsorb ammonia gas through coordination reactions. The activated carbon fiber felt loaded with basic copper carbonate can generate copper salt after adsorbing HCl, and can be regenerated by impregnating with sodium carbonate to regenerate basic copper carbonate. The process of preparing the platinum-cerium binary titanate photothermal synergistic catalyst using a combination of hydrothermal and stripping-reassembly methods retains the core steps of both methods, such as hydrothermal reaction, laminated glass, and recombination reaction, while simplifying drying and calcination steps, saving time and cost in catalyst preparation. This invention achieves simultaneous VOCs removal and tin recovery by using adsorption, photocatalysis, or thermocatalysis to degrade VOCs while separating and recovering tin dust. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the device of the present invention;

[0013] Figure 2 The photothermal degradation rate and thermocatalytic degradation rate of toluene for the catalyst.

[0014] Wherein: 1-Equipment housing; 2-Filter layer; 3-Impurity removal layer; 4-VOCs degradation layer; 5-Outlet. Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Example 1

[0016] like Figure 1 As shown, a device for simultaneously removing tin dust waste gas and VOCs includes a device housing 1, a cylindrical filter layer 2, a dirt removal layer 3, a VOCs degradation layer 4 arranged sequentially from the outside to the inside of the device housing, and an outlet 5 on one side of the device housing. This design allows the organic waste gas containing dust and acidic or alkaline gases to be pretreated, filtering out the dust and absorbing or adsorbing away the acidic or alkaline gases, thus preventing these components from causing blockage or corrosion / poisoning when passing through the VOCs degradation layer. Furthermore, the outlet 5 is connected to the VOCs degradation layer 4, and the two have the same diameter; the VOCs degradation layer 4 includes a catalyst layer, a heating tube, and an ultraviolet lamp.

[0017] Filter layer 2 selects different filter media according to the different temperatures of tin dust exhaust gas. When the exhaust gas temperature is measured to be below 250℃, polytetrafluoroethylene filter media with acid and alkali corrosion resistance, wear resistance and high temperature resistance is selected. The pore size range is 0.08-3.0μm and the porosity is greater than 85%.

[0018] The impurity removal layer 3 is composed of two layers of modified high-temperature resistant activated carbon fiber felt. One layer undergoes sulfonation modification to adsorb and remove alkaline gas NH3 from the waste gas. The sulfonation modification process uses both concentrated sulfuric acid and a 10 mol / L cuprous sulfate solution as sulfonating agents, with a volume ratio of concentrated sulfuric acid to cuprous sulfate solution of 1:2. Sulfonation is first carried out at 90℃ for 12 hours, followed by further heating to 140℃ for 12 hours. The other layer undergoes basic copper carbonate loading modification to adsorb and remove acidic gases such as HCl and H2S. The basic copper carbonate loading process involves impregnating the activated carbon fiber felt with a copper nitrate solution to allow the Cu... 2+ The activated carbon fiber felt is bonded to the functional groups on the surface of the activated carbon fiber felt, dried, and then impregnated with sodium carbonate solution to form basic copper carbonate on the surface of the activated carbon fiber felt. The molar ratio of copper nitrate to sodium carbonate used is 1:0.7. The sulfonated modified activated carbon fiber felt is marked as ACF-SA2, and the activated carbon fiber felt modified with basic copper carbonate is marked as ACF-CuCO3.

[0019] VOCs degradation layer 4 selects different catalysts based on the different temperatures of the tin dust exhaust gas. When the exhaust gas temperature is below 250℃, a photothermal synergistic catalyst is used. The preparation method of the photothermal synergistic catalyst is a combination of hydrothermal method and stripping-reassembly method. First, under magnetic stirring, 15 mL of tetrabutyl titanate was added dropwise to 100 mL of a 10 mol / L sodium hydroxide ethanol solution (ethanol to water volume ratio of 3:7). After mixing thoroughly, the mixture was subjected to a hydrothermal reaction at 130 °C for 24 h to obtain titanate nanotube precipitate. After cooling, the precipitate was washed with water until neutral, and then repeatedly impregnated with 0.1 mol / L hydrochloric acid until the solution was neutral before centrifugation to obtain titanate nanotubes. The titanate nanotubes were then soaked in 69% ethylamine for 12 h to peel off the titanate ion nanotube layer sol. Then, under stirring, 10 mL of 0.02 mol / L chloroplatinic acid hexahydrate and 10 mL of 0.5 mol / L cerium acetate solution were added dropwise. Under magnetic stirring for 24 h, a recombination reaction was carried out to generate a precipitate. After centrifugation, washing, and drying, the precipitate was reduced with H2 at 350 °C for 4 h to obtain a platinum-cerium binary titanate photothermal synergistic catalyst, labeled PtCe-Titan.

[0020] The above equipment is used as follows: the dust-laden gas flows in the direction shown by the arrow, passing through the filter layer, the impurity removal layer, and the VOCs degradation layer in sequence, removing tin dust, HCl, H2S, NH3, and VOCs in succession. The purified gas flows along the innermost VOCs degradation layer to the outlet for discharge. The filter bags are cleaned by pulse cleaning. The filtered gas is monitored in real time. When acidic or alkaline gases such as NH3, HCl, and H2S are detected to exceed the standard, the impurity removal layer is replaced in time. The old impurity removal layer can be recycled after regeneration. Example 2

[0021] A device for simultaneously removing tin dust and VOCs from waste gas includes a housing 1, a cylindrical filter layer 2, a dust removal layer 3, a VOCs degradation layer 4 arranged sequentially from the outside to the inside of the housing, and an outlet 5 on one side of the housing. This design allows for pretreatment of organic waste gas containing dust and acidic / alkaline gases, filtering out the dust and absorbing or adsorbing away the acidic / alkaline gases, thus preventing these components from clogging or corroding / poisoning when passing through the VOCs degradation layer. Furthermore, the outlet 5 is connected to the VOCs degradation layer 4, and both have the same diameter; the VOCs degradation layer 4 includes a catalyst layer, a heating element, and an ultraviolet lamp.

[0022] Filter layer 2 selects different filter media according to the different temperatures of tin dust exhaust gas. When the exhaust gas temperature is higher than 250℃, 316L stainless steel fiber felt with corrosion resistance, wear resistance and ultra-high temperature resistance is selected, with a pore size range of 0.1-3.0μm.

[0023] The impurity removal layer 3 is composed of two layers of modified high-temperature resistant activated carbon fiber felt. One layer undergoes sulfonation modification to adsorb and remove alkaline gas NH3 from the waste gas. The sulfonation modification process uses both concentrated sulfuric acid and a 10 mol / L cuprous sulfate solution as sulfonating agents, with a volume ratio of concentrated sulfuric acid to cuprous sulfate solution of 1:2. Sulfonation is first carried out at 90℃ for 12 hours, followed by further heating to 140℃ for 12 hours. The other layer undergoes basic copper carbonate loading modification to adsorb and remove acidic gases such as HCl and H2S. The basic copper carbonate loading process involves impregnating the activated carbon fiber felt with a copper nitrate solution to allow the Cu... 2+ The activated carbon fiber felt is bonded to the functional groups on the surface of the activated carbon fiber felt, dried, and then impregnated with sodium carbonate solution to form basic copper carbonate on the surface of the activated carbon fiber felt. The molar ratio of copper nitrate to sodium carbonate used is 1:0.7. The sulfonated modified activated carbon fiber felt is marked as ACF-SA2, and the activated carbon fiber felt modified with basic copper carbonate is marked as ACF-CuCO3.

[0024] Selection and preparation of VOCs degradation layer 4: For exhaust gas temperatures above 250℃, a platinum-cerium TiO2 nanotube thermally activated catalyst was used. The preparation method combined hydrothermal and vacuum impregnation: First, under magnetic stirring, 15 mL of titanate n-butyl ester was added dropwise to 100 mL of a 10 mol / L sodium hydroxide ethanol solution (ethanol to water volume ratio 3:7). After thorough mixing, the mixture was hydrothermally reacted at 130℃ for 24 h to obtain titanate nanotube precipitate. After cooling, the precipitate was washed with water until neutral, and then... The sample was impregnated with 0.1 mol / L hydrochloric acid until the solution was neutral, and then centrifuged to obtain titanate nanotubes. Next, 10 mL of 0.02 mol / L chloroplatinic acid hexahydrate and 10 mL of 0.5 mol / L cerium acetate solution were mixed, and the prepared titanate nanotubes were added to the mixture and stirred evenly. The sample was then vacuum impregnated at 60 °C for 12 h in a vacuum drying oven. After drying the sample, it was calcined at 350 °C for 4 h to obtain a platinum-cerium supported TiO2 nanotube thermally activated catalyst, labeled as PtCe-TiNT. Comparative Example 1

[0025] The difference from Example 1 is:

[0026] Filter layer selection: The exhaust gas temperature is below 250℃, so acid-resistant and high-temperature-resistant glass fiber is selected. The pore size of the glass fiber filter media is 0.08-3.0μm, and the porosity is greater than 85%.

[0027] The impurity removal layer consists of two layers of modified high-temperature resistant activated carbon fiber felt. One layer undergoes sulfonation modification to adsorb and remove alkaline gas NH3 from the waste gas. The sulfonation modification process of the activated carbon fiber felt uses only concentrated sulfuric acid as the sulfonating agent, first sulfonating at 90℃ for 12 hours, and then raising the temperature to 140℃ for sulfonation for 12 hours. The other layer undergoes copper hydroxide loading modification to adsorb and remove acidic gases such as HCl and H2S. The copper hydroxide loading process of the activated carbon fiber felt involves first impregnating the activated carbon fiber felt with copper nitrate solution to make the Cu... 2+ The activated carbon fiber felt is bonded to the functional groups on the surface of the activated carbon fiber felt, dried, and then impregnated with sodium hydroxide solution to form copper hydroxide on the surface of the activated carbon fiber felt. The molar ratio of copper nitrate to sodium hydroxide used is 1:0.7. The sulfonated modified activated carbon fiber felt is marked as ACF-SA1, and the activated carbon fiber felt modified with basic copper carbonate is marked as ACF-Cu(OH)2.

[0028] VOCs Degradation Layer: Different catalysts are selected according to the different temperatures of the tin dust exhaust gas. For exhaust gas temperatures below 250℃, a thermally activated catalyst using platinum-cerium TiO2 nanotubes is used. The preparation method is a combination of hydrothermal and vacuum impregnation: First, under magnetic stirring, 15 mL of tetrabutyl titanate is added dropwise to 100 mL of a 10 mol / L sodium hydroxide ethanol solution (ethanol to water volume ratio of 3:7). After the two are mixed evenly, a hydrothermal reaction is carried out at 130℃ for 24 h to obtain titanate nanotube precipitate. After cooling, the precipitate is washed with water. The solution was repeatedly impregnated with 0.1 mol / L hydrochloric acid until neutral, and then centrifuged to obtain titanate nanotubes. Next, 10 mL of 0.02 mol / L chloroplatinic acid hexahydrate and 10 mL of 0.5 mol / L cerium acetate solution were mixed, and the prepared titanate nanotubes were added to the mixture and stirred evenly. The mixture was then vacuum impregnated at 60 °C for 12 h in a vacuum drying oven. After drying the sample, it was calcined at 350 °C for 4 h to obtain a platinum-cerium supported TiO2 nanotube thermally activated catalyst, labeled as PtCe-TiNT. Comparative Example 2

[0029] The difference from Example 2 is:

[0030] Filter layer selection: When the exhaust gas temperature is higher than 250℃, polytetrafluoroethylene (PTFE) filter material with acid and alkali corrosion resistance, wear resistance, and high temperature resistance is selected. The pore size range is 0.08-3.0μm, and the porosity is greater than 85%.

[0031] VOCs degradation layer: Different catalysts are selected according to the different temperatures of the tin dust exhaust gas. When the exhaust gas temperature is higher than 250℃, a platinum-cerium binary titanate photothermal synergistic catalyst is used. The preparation method is a combination of hydrothermal method and stripping-reassembly method. First, under magnetic stirring, 15 mL of tetrabutyl titanate was added dropwise to 100 mL of a 10 mol / L sodium hydroxide ethanol solution (ethanol to water volume ratio of 3:7). After mixing thoroughly, the mixture was subjected to a hydrothermal reaction at 130 °C for 24 h to obtain titanate nanotube precipitate. After cooling, the precipitate was washed with water until neutral, and then repeatedly impregnated with 0.1 mol / L hydrochloric acid until the solution was neutral before centrifugation to obtain titanate nanotubes. The titanate nanotubes were then soaked in 69% ethylamine for 12 h to peel off the titanate ion nanotube layer sol. Then, under stirring, 10 mL of 0.02 mol / L chloroplatinic acid hexahydrate and 10 mL of 0.5 mol / L cerium acetate solution were added dropwise. Under magnetic stirring for 24 h, a recombination reaction was carried out to generate a precipitate. After centrifugation, washing, and drying, the precipitate was reduced with H2 at 350 °C for 4 h to obtain a platinum-cerium binary titanate photothermal synergistic catalyst, labeled PtCe-Titan.

[0032] The acid resistance, alkali resistance and 250℃ temperature resistance of the polytetrafluoroethylene (PTFE) filter media and glass fiber filter media used in the test examples and comparative examples were tested. The acid resistance, alkali resistance and 300℃ temperature resistance of the stainless steel fiber blanket and glass fiber filter media were also tested. The results are as follows: (1) The PTFE filter media, glass fiber and stainless steel fiber blanket were soaked in concentrated hydrochloric acid respectively. After 48 hours, the first two were found to be basically unchanged, while the third was corroded and dissolved, leaving only a part of the residue. This indicates that the PTFE filter media and glass fiber have good acid corrosion resistance, while the stainless steel fiber blanket is not acid corrosion resistant. This is because elements such as iron in stainless steel can react with acid to form metal ions; (2) (2) The three filter media were soaked in 10 mol / L sodium hydroxide solution respectively. After 48 hours, they were taken out and found that the polytetrafluoroethylene filter media and stainless steel fiber had basically no change, indicating that the two had good alkali corrosion resistance. The glass fiber was corroded and dissolved, leaving only a part of the residue. Since the glass fiber can react with alkali, its alkali corrosion resistance is very poor. (3) The three filter media were placed at 250℃ for 12 hours and then taken out. It was found that none of the three showed obvious changes. After being placed at 300℃ for 12 hours, they were taken out again. It was found that the stainless steel fiber blanket still did not show obvious changes, while the polytetrafluoroethylene and glass fiber filter media were obviously deformed, causing the filter holes to be blocked and unusable.

[0033] The dynamic adsorption performance of two sulfonated modified activated carbon fiber felts from two embodiments and a comparative example of the present invention on waste gas containing alkaline gas NH3 (30 mg / L) was tested, and the results are shown in Table 1. The NH3 breakthrough times of ACF-SA1 in the comparative example and ACF-SA2 in the embodiments of the present invention were 7.46 h and 11.29 h, respectively, while the NH3 adsorption capacities were 183 mg / g and 265 mg / g, respectively. Compared with ACF-SA1 in the comparative example, the NH3 adsorption capacity of ACF-SA2 in the present invention increased by 44.8%. This is because ACF-SA1 only uses concentrated sulfuric acid as a sulfonating agent for modification, while the modification process of ACF-SA2 uses both concentrated sulfuric acid and 10 mol / L cuprous sulfate solution as sulfonating agents. The increased amount of sulfonating agent improves the sulfonation modification effect and thus improves the NH3 adsorption performance. In addition, cuprous ions also have good adsorption performance for NH3. Therefore, the NH3 adsorption capacity of ACF-SA2 used in the present invention is significantly improved.

[0034] Table 1. Test results of alkaline gas adsorption performance of modified activated carbon fiber felt

[0035] Modified activated carbon fiber felt <![CDATA[NH3 breakthrough time (h)]]> <![CDATA[NH3 adsorption capacity (mg / g)]]> <![CDATA[ACF-SA1 in the comparative example]]> 7.46 183 <![CDATA[ACF-SA2 in Examples 1 and 2]]> 11.29 265

[0036] The dynamic adsorption performance of two alkali-modified activated carbon fiber felts for waste gas containing acidic gas HCl (35 mg / L) was tested using a similar method described above. The results are shown in Table 2. The HCl breakthrough times of ACF-Cu(OH)2 in the comparative example and ACF-CuCO3 in the present invention were 5.82 h and 7.96 h, respectively, while the HCl adsorption capacities were 214 mg / g and 293 mg / g, respectively. Compared to ACF-Cu(OH)2, the HCl adsorption capacity of ACF-CuCO3 increased by 36.9%. This is because the sodium hydroxide used in the modification process of ACF-Cu(OH)2 is a strong alkali, and its reaction rate with copper ions is too fast, leading to the aggregation of basic adsorption sites of copper hydroxide, which affects its adsorption performance. In contrast, ACF-CuCO3 uses weakly basic sodium carbonate as a precipitant. Due to the slower reaction rate, the generated basic copper carbonate adsorption sites have better dispersion, thus exhibiting better adsorption performance for HCl. Furthermore, the activated carbon fiber felt loaded with basic copper carbonate can generate copper salts after adsorbing HCl, and can be regenerated by impregnating with sodium carbonate to regenerate basic copper carbonate.

[0037] Table 2. Test results of acid gas adsorption performance of modified activated carbon fiber felt

[0038] Modified activated carbon fiber felt HCl breakthrough time (h) HCl adsorption capacity (mg / g) <![CDATA[ACF-Cu(OH)2 in the comparative example]]> 5.82 214 <![CDATA[ACF-CuCO3 in the embodiment]]> 7.96 293

[0039] The photothermal catalytic activity of PtCe-Titan and PtCe-TiNT catalysts for toluene was tested at 240℃ and under UV irradiation, and the thermal catalytic activity of the two catalysts for toluene was tested at 280℃. The results showed that the photothermal degradation rates of toluene by PtCe-Titan and PtCe-TiNT were 100% and 94%, respectively, and the thermal catalytic degradation rates were 70% and 86%, respectively. Therefore, in the toluene degradation reaction, PtCe-Titan has better photothermal synergistic catalytic performance, while PtCe-TiNT has better thermal catalytic performance.

Claims

1. A device for simultaneously removing tin dust waste gas and VOCs, characterized in that: The equipment includes a housing (1), and inside the housing, a cylindrical filter layer (2), a dust removal layer (3), a VOCs degradation layer (4), and an outlet (5) on one side of the housing, arranged sequentially from the outside to the inside. The outlet (5) is connected to the VOCs degradation layer (4), and the two have the same diameter. The VOCs degradation layer (4) includes a catalyst layer, a heating tube, and an ultraviolet lamp. The filter layer (2) is selected according to the different temperatures of the tin dust exhaust gas. When the temperature is below 250℃, polytetrafluoroethylene filter material with acid and alkali corrosion resistance, wear resistance, and high temperature resistance is selected, with a pore size range of 0.08-3μm and a porosity greater than 85%. When the temperature is above 250℃, 316L stainless steel fiber felt with corrosion resistance, wear resistance, and ultra-high temperature resistance is selected. The pore size range is 0.1-3μm; the impurity removal layer (3) is composed of two layers of modified adsorbent materials. The base material of both layers of adsorbent materials is high-temperature resistant activated carbon fiber felt. One layer is sulfonated to adsorb and remove alkaline gas NH3 in the waste gas. The sulfonation modification process of activated carbon fiber felt uses two sulfonating agents: concentrated sulfuric acid and 10mol / L cuprous sulfate solution. The volume ratio of concentrated sulfuric acid to cuprous sulfate solution is 1:

2. It is first sulfonated at 90℃ for 12h, and then heated to 140℃ for sulfonation for 12h. The other layer is modified with basic copper carbonate loading to adsorb and remove HCl and H2S and other acidic gases. The basic copper carbonate loading process of activated carbon fiber felt is first impregnated with copper nitrate solution to make Cu 2+ The copper nitrate is bonded to the functional groups on the surface of the activated carbon fiber felt, dried, and then impregnated with sodium carbonate solution to form basic copper carbonate on the surface of the activated carbon fiber felt. The molar ratio of copper nitrate to sodium carbonate used is 1:0.

7.

2. The equipment for simultaneously removing tin dust and VOCs from exhaust gas according to claim 1, characterized in that: VOCs degradation layer (4) Select different catalysts according to the different temperatures of tin dust exhaust gas. When the temperature is below 250℃, use photothermal synergistic catalyst, and when the temperature is above 250℃, use thermally activated catalyst.

3. The equipment for simultaneously removing tin dust and VOCs according to claim 2, characterized in that: The photothermal synergistic catalyst was prepared using a hydrothermal method combined with a stripping-reassembly method. First, titanate nanotubes were prepared using a hydrothermal method with tetrabutyl titanate and sodium hydroxide solution as raw materials, and then acid-washed to obtain titanate nanotubes. Next, the titanate nanotubes were soaked in ethylamine to obtain a titanate ion nanotube layer sol, and then chloroplatinic acid hexahydrate and cerium acetate solution were added dropwise. After precipitation, washing, and drying, the platinum-cerium binary titanate photothermal synergistic catalyst was obtained.

4. The equipment for simultaneously removing tin dust and VOCs from exhaust gas according to claim 3, characterized in that: The thermally activated catalyst was prepared by a hydrothermal method combined with a vacuum impregnation method. First, titanate nanotubes were prepared by hydrothermal method using titanate n-butyl ester and sodium hydroxide solution as raw materials. After acid washing, water washing and drying, titanate nanotubes were obtained. Second, the titanate nanotubes were vacuum impregnated with chloroplatinic acid hexahydrate and cerium acetate solution. After drying and calcination, platinum-cerium supported TiO2 nanotube thermally activated catalyst was obtained.

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