Preparation method of comprehensive protection ethylene oxide and cyanogen chloride adsorption material

Abstract

The application discloses a preparation method of an adsorbing material for comprehensive protection of ethylene oxide and cyanogen chloride, and belongs to the technical field of adsorbents. The method uses activated carbon as a carrier, impregnates a basic metal complex solution for multiple times, and loads metal oxide components such as potassium, copper, zinc and silver in the pores of the activated carbon to obtain impregnated activated carbon with adsorption and catalysis functions. The impregnated activated carbon is mixed and packed with porous zeolite molecular sieves rich in acid sites to form a composite adsorbing material. The material can efficiently hydrolyze EO and CNCl which are difficult to be treated by conventional adsorbents, and has good application value in the fields of chemical protection and air purification.

Description

Technical Field

[0001] This invention relates to the field of protective materials technology, specifically to a method for preparing a comprehensive protective EO and CNCl adsorbent material. Background Technology

[0002] Activated carbon possesses significant advantages as an adsorbent material, primarily due to its abundant microporous and mesoporous structures resulting in an extremely large specific surface area, giving it exceptional adsorption capacity and enabling it to efficiently capture various substances. Modification of activated carbon substrates has become an indispensable part of protection against industrial gases and chemical warfare agents. With the development of protective materials research, studies on the protection of impregnated activated carbon materials against industrial gases and classic chemical agents are becoming increasingly comprehensive, demonstrating a certain level of comprehensive protection against both conventional industrial gases (ammonia, sulfur dioxide, hydrogen sulfide, etc.) and classic chemical warfare agents (cyanide, etc.). Impregnating activated carbon with a series of metal components (such as potassium, copper, zinc, and silver) endows it with the ability to adsorb and decompose classic chemical warfare agents and acidic / alkaline gases. However, conventional impregnated carbon still cannot solve the problem of efficient adsorption of highly polar small molecules such as ethylene oxide, failing to meet the current development requirements for miniaturized and lightweight chemical protection equipment. Ethylene oxide (EO), as a crucial low-temperature chemical disinfectant and intermediate in chemical raw materials, has wide applications in both military and civilian sectors. While bringing convenience to production and daily life, it also poses serious hazards. It is a central nervous system depressant, stimulant, and protoplasmic poison with strong acute toxicity. Furthermore, EO gas exhibits extremely high flammability and explosiveness, with a very wide explosive limit range; even a small amount of EO gas in the air can form an explosive mixture, which will violently explode upon contact with an open flame. Therefore, developing adsorbent materials with comprehensive protective capabilities against EO and CNCl has significant application value.

[0003] There is currently limited research on comprehensive protective materials for EO and CNCl. The patent application number 202010142881.6, "A method for preparing a broad-spectrum protective impregnated activated carbon", uses activated carbon as a carrier and loads substances such as copper oxide and zinc oxide through an in-situ generation of oxide crystals, achieving comprehensive protection against industrial toxic gases and classic chemical agents, but it does not involve the adsorption of ethylene oxide.

[0004] Patent application number 201310857207.3, entitled "A Filter Canister for Ethylene Oxide and Its Application," designs a three-layer detachable filter canister. By filling it with unmodified activated carbon, zeolite, and solid superacid, it achieves purification of ethylene oxide exhaust gas at room temperature and pressure. However, this solution is a protective device specifically for ethylene oxide and does not address protection against the classic toxic agent cyanide.

[0005] In fact, the key catalytic agents for targeting ethylene oxide are zeolite materials with specific acidic sites and superacid catalysts. However, cyanide molecules produce acidic substances during catalytic hydrolysis. Adding too many acidic sites reduces the hydrolysis efficiency of cyanide, significantly impacting protection against this type of poison. While impregnated activated carbon alone can physically adsorb and capture a large number of target molecules, its ability to catalyze the hydrolysis of ethylene oxide is insufficient. Once saturation adsorption is reached, ethylene oxide will penetrate the protective layer, thus losing its protective effectiveness.

[0006] Current chemical protective equipment uses activated carbon as its core material, but it has functional limitations and cannot simultaneously meet the high-efficiency protection requirements against cyanogen chloride and ethylene oxide. Impregnated carbon, by loading impregnating agents, can meet the protection requirements against some industrial gases and chemical warfare agents; molecular sieves, relying on their own chemical and physical adsorption properties, can achieve high-efficiency adsorption of ethylene oxide. However, neither impregnated carbon nor molecular sieve materials alone can meet the comprehensive protection requirements in complex scenarios. Therefore, a composite bed strategy of impregnated carbon and molecular sieves is an effective way to achieve high-efficiency comprehensive protection against ethylene oxide and cyanogen chloride. It can balance the protective dosage and ventilation resistance of the equipment without increasing the bed thickness, showing good application prospects in the field of chemical protection. Summary of the Invention

[0007] This invention provides a method for preparing impregnated carbon adsorbent materials and a protection strategy that combines zeolite molecular sieves to address the comprehensive protection against toxic substances, such as chemical warfare agents like cyanogen chloride and highly toxic, flammable, and explosive hazardous chemicals like ethylene oxide.

[0008] To achieve the above technical objectives, the technical approach adopted by this invention is as follows: (1) Weigh out soluble copper salt and soluble zinc salt, slowly add them to the ammonia solution, heat and stir until uniform, then add ammonium bicarbonate and silver nitrate, adjust the alkalinity of the impregnation solution and add soluble potassium salt until a stable dark blue metal complex impregnation solution is formed. (2) Spray the above impregnation solution into a reaction vessel containing activated carbon at a certain temperature, keep it warm and let it stand for a certain time, and then heat it up to activate it. (3) Weigh out soluble phosphate and soluble zirconium salt and slowly add them to the pure water-ethanol mixed solution. Maintain a certain temperature and heat until the solution is uniformly stirred to form a stable impregnation solution. (4) The impregnated carbon that has been activated twice is heated again. The impregnation liquid prepared in step (3) is heated and sprayed evenly onto the activated carbon. After being kept warm and standing for a period of time, it is heated and activated. After being subjected to anti-gradient aging treatment, the impregnated activated carbon material is obtained. (5) After mixing silicon source, aluminum source, nano source, template agent and deionized water to form a sol, the sol is subjected to pre-crystallization, static crystallization, separation, washing, drying and calcination to remove the template agent, and ZSM-5 zeolite molecular sieve raw powder is obtained. (6) The raw zeolite molecular sieve powder is mixed with boehmite binder, guar gum powder, dilute acid solution and deionized water to form a plastic body. After extrusion molding, it is dried and baked to obtain ZSM-5 zeolite molecular sieve. (7) The ZSM-5 zeolite molecular sieve was combined with the prepared activated impregnated carbon for filling to obtain an adsorbent material for protecting against ethylene oxide and cyanide chloride.

[0009] In the steps described above, the soluble copper salt is copper sulfate, copper chloride, or basic copper carbonate. Soluble zinc salts are zinc carbonate or basic zinc carbonate; Soluble potassium salts include potassium carbonate and potassium hydroxide; Soluble phosphates are dipotassium hydrogen phosphate, ammonium dihydrogen phosphate, or ammonium phosphate; Soluble zirconium salts are zirconium nitrate or zirconium chloride.

[0010] In step (2), the impregnation liquid is divided into two parts. The first part of the impregnation liquid is sprayed into the reactor containing activated carbon. After keeping it warm and letting it stand for a certain time, it is heated and activated. Then the second part of the impregnation liquid is sprayed into the reactor containing activated carbon. After keeping it warm and letting it stand for a certain time, it is heated and activated.

[0011] The volume fraction of the first impregnation solution is 50-60%; the volume fraction of the second impregnation solution is 40-50%.

[0012] The first impregnation solution also includes ammonia water with a mass fraction of 40-50%, and the ammonia water is added to make up to 110-120% of the mass of activated carbon. The second impregnation solution also includes ammonia water with a mass fraction of 60-65%, which is added to make up to 100-105% of the activated carbon mass.

[0013] The activation temperature is 120~180℃, and the activation time is 1~2h.

[0014] In step (3), the impregnation solution for the second impregnation is 70% to 80% of the mass of activated carbon, and the impregnation solution contains phosphorus and zirconium. The anti-aging agent used in the step (4) gradation process is triethylenediamine, and the addition amount is 2% to 6%.

[0015] The tiered anti-aging process of the anti-aging agent involves adding the anti-aging agent in stages of 0.5-2% to achieve at least 3-6 anti-aging processes.

[0016] In step (5), the silicon source is selected from one or more of silica sol, water glass, white carbon black or tetraethyl orthosilicate, preferably industrial grade silica sol; The aluminum source is selected from aluminum sulfate, sodium aluminate, boehmite, or metallic aluminum, preferably aluminum sulfate or sodium aluminate; the sodium source is selected from sodium hydroxide, sodium aluminate, or water glass; the template agent is tetrapropylammonium hydroxide or hexamethyleneimine. The molar ratio of the silicon source, aluminum source, nano source and template agent is in the range of 1 : (0.01~0.04) : (0.01~0.03) : (0.1~0.4) : (15~40), with a preferred silicon-aluminum ratio of 40~80.

[0017] The pre-crystallization temperature is 80~140℃, and the time is 1~8h; The static crystallization temperature is 170~180℃, and the time is 12-36h.

[0018] In step (6), the drying operation is to dry in an oven at 110~120℃ for 6~12h; the calcination operation is to dry at a constant temperature of 550~600℃ for 4~6h.

[0019] In step (7), the filling strategy includes multi-layer material layering, wherein the multi-layer material layering includes filling different anti-aging impregnated carbon samples and molecular sieve materials in proportion. When the amount of anti-aging agent added to the activated impregnated carbon is more than 3%, it is a water-absorbing layer; when it is less than 3%, it is a carbon adsorption layer. The water-absorbing layer, carbon adsorption layer, and ZSM-5 zeolite molecular sieve are loaded in a mass ratio of 1:(4~6):(1.5~4.5) from top to bottom.

[0020] In some preferred cases, the amount of anti-aging agent added is divided into three layers: 3%~6% for the water-absorbing layer, 0.5%~3% for the carbon adsorption layer, and the molecular sieve without anti-aging agent (serving as the molecular sieve adsorption layer). The water-absorbing layer, carbon adsorption layer, and molecular sieve adsorption layer are filled sequentially from top to bottom (the water-absorbing layer and carbon adsorption layer can be composed of various anti-aging impregnated carbons), and the filling composition is controlled at a mass ratio of 1:(4~6):(1.5~4.5).

[0021] In some preferred embodiments, the steps include the following detailed steps: I. A method for preparing impregnated activated carbon, comprising the following steps: (a1) Weigh out soluble copper salt and soluble zinc salt, slowly add them to an ammonia solution, maintain a certain temperature while heating, and stir evenly with a stirrer. Then add ammonium bicarbonate and silver nitrate to adjust the alkalinity of the impregnation solution and add soluble potassium salt until a stable dark blue metal complex impregnation solution is formed.

[0022] (a2) Divide the above impregnation solution into two portions. At a certain temperature, spray the first portion of the impregnation solution into the reactor containing activated carbon through a spraying device and keep it at a certain temperature for a certain period of time.

[0023] (a3) Transfer the activated carbon impregnated with the metal solution to the activation equipment and activate it at 120~180℃ for 1~2h.

[0024] (a4) Reheat the impregnated carbon that has completed the first activation, spray the heated impregnation liquid evenly onto the activated carbon, keep it warm and stand for a period of time, and after it has fully absorbed the impregnation liquid, transfer it to the activation equipment for a second activation (same as step a3).

[0025] (a5) Weigh out soluble phosphate and soluble zirconium salt and slowly add them to a pure water-ethanol mixture. Maintain a certain temperature and heat the mixture while stirring it evenly with a stirrer until a stable impregnation solution is formed.

[0026] (a6) The impregnated carbon that has completed the second activation is heated again. The impregnation liquid prepared in (a5) is heated and sprayed evenly onto the activated carbon. After being kept warm and standing for a period of time, the impregnation liquid is fully absorbed and then transferred to the activation equipment for the third activation. After the anti-gradient aging treatment, the impregnated activated carbon material is obtained.

[0027] II. Preparation and molding of zeolite molecular sieves: (b1) After mixing silicon source, aluminum source, nano source, template agent and deionized water to form a sol, add it to a stainless steel reactor and precrystallize at 80~140℃ for 1~8h to obtain a precrystallized colloid.

[0028] (b2) The precrystallized colloid was statically crystallized at 170~180℃ for 12~36h, and then separated, washed, dried and calcined to remove the template agent to obtain ZSM-5 zeolite molecular sieve raw powder.

[0029] (b3) The zeolite molecular sieve raw powder was mixed with boehmite binder, guar gum powder, dilute acid solution and deionized water to form a plastic body. The wet rod-shaped preform was extruded through an extruder and then cut into short rods with a knife. After drying and high-temperature baking, rod-shaped ZSM-5 zeolite molecular sieves were obtained.

[0030] (b4) The synthesized rod-shaped zeolite material is used in combination with activated impregnated carbon for filling. Before filling, the zeolite molecular sieve needs to be vacuum dried for 4-6 hours. After drying, it needs to be equilibrated in a desiccator for 4-12 hours before filling. The filling strategy is mixed filling and layered filling.

[0031] In step a1), the soluble copper salt is copper sulfate, copper chloride, or basic copper carbonate; the soluble sodium salt is sodium bicarbonate; the soluble potassium salt is potassium carbonate or potassium hydroxide; the soluble zinc salt is zinc carbonate or basic zinc carbonate; the soluble phosphate salt is dipotassium hydrogen phosphate, ammonium dihydrogen phosphate, or ammonium phosphate; and the soluble zirconium salt is zirconium nitrate or zirconium chloride.

[0032] In step a1), the content of copper is 4% to 7%; the content of potassium is 1% to 5%; the content of zinc is 0.5% to 4%; and the content of silver is 0.1% to 0.5%.

[0033] In step a1), the heating can be water bath heating, microwave heating, infrared heating, etc., and the solution temperature is maintained at 40~55℃.

[0034] In step a2), the impregnation solution is divided into two parts, 60% and 40%. During the first spray, ammonia water is used to make up to 110% of the activated carbon mass. The activated carbon should be coconut shell activated carbon with a mesh size of 14-25 and a water solubility of 95% to 110%, and the temperature should be raised to 40-60℃ before spraying.

[0035] In step a4), the impregnation solution is replenished with ammonia water to 105% of the activated carbon mass, and heated to 40-60℃ before spraying; the activation temperature is 150-180℃, and the activation time is 1-2 hours.

[0036] In step a5), the amount of phosphate added is 0.5% to 1.5%; the content of zirconium is 0.5% to 1.5%; and the volume ratio of pure water to ethanol is 4:1 to 1:1.

[0037] In step a6), the impregnation solution is replenished with pure water to 70% to 80% of the activated carbon mass, and heated to 40-60°C before spraying; the activation temperature is 170-180°C, and the activation time is 1-2 hours; the anti-aging agent is triethylenediamine and graded anti-aging is carried out, with an addition amount of 2% to 6%.

[0038] In step b1), the silicon source is selected from one or more of silica sol, water glass, silica, or tetraethyl orthosilicate, preferably industrial-grade silica sol; the aluminum source is selected from one of aluminum sulfate, sodium aluminate, boehmite, or metallic aluminum, preferably aluminum sulfate or sodium aluminate; the sodium source is selected from sodium hydroxide, sodium aluminate, or water glass. The template agent is tetrapropylammonium hydroxide or hexamethyleneimine.

[0039] In step b1), the molar ratio of silicon source, aluminum source, nano source, and template agent ranges from 1 : (0.01~0.04) : (0.01~0.03) : (0.01~0.04) : (15~40). A silicon-to-aluminum ratio of 40~80 is preferred.

[0040] In step b3), the drying operation is to dry in an oven at 110~120℃ for 6~12h; the calcination operation is to dry at a constant temperature of 550~600℃ for 4~6h.

[0041] In step b4), the filling strategy includes multi-layer material layered filling and direct mixing. The multi-layer material layered filling includes filling different anti-aging impregnated carbon samples and molecular sieve materials in proportion, divided into a strongly hydrophilic layer, a weakly hydrophilic layer and a hydrophobic layer, with a volume ratio of 1:(3.5~5.5):(1.5~3.5) or a mass ratio of 1:(4~6):(1.5~4.5).

[0042] Compared with the prior art, the beneficial effects of the present invention are: In conventional ethylene oxide protection solutions, solid acidic catalysts (such as synthetic zeolite molecular sieves) are often used to achieve adsorption and decomposition. Synthetic zeolite molecular sieve catalysts have the advantages of narrow pore size distribution and regular structure, exhibiting good absorption and decomposition performance for some alkaline gases and acid-catalyzed gases. However, these catalysts have strong catalytic selectivity and negatively impact alkaline-catalyzed reactions. Furthermore, the catalytic activity of molecular sieves depends on adsorption sites in their internal microporous structure, which are easily occupied by water molecules. The hydrogen bond network formed after water molecule adsorption causes pore blockage, reducing catalyst lifetime. Therefore, in practical applications, they need to be used in combination with other materials to improve the versatility of the protective equipment.

[0043] This invention uses activated carbon as a carrier, employing a multiple loading process to impregnate and adsorb metal ions into the pores of the activated carbon. At high temperatures, metal oxides are generated in situ within the pores, creating active catalytic sites and providing basic comprehensive protection against chemical warfare agents and small molecules like ethylene oxide. Through process and formulation control, the abundant micropores and mesopores of the activated carbon carrier are rationally utilized to adsorb and catalyze the target toxic molecules. The impregnated carbon is further mixed and packed with synthetic zeolite molecular sieves, with a high-density mixture placed in the lower layer and a low-density mixture placed in the upper layer (the density of the zeolite molecular sieve is greater than that of the impregnated carbon, and the lower the zeolite content, the lower the density of the mixture). This constructs a tiered structure with a highly hydrophilic upper layer and a highly hydrophobic lower layer, mitigating the deactivation of the molecular sieve material caused by high-humidity gases and reducing ineffective protective layers. This effectively utilizes the differences in hydrophilicity and hydrophobicity between the two materials, maximizing the use of their respective active sites, thereby achieving precise and efficient protection against cyanide and ethylene oxide gases. Detailed Implementation

[0044] The invention will be specifically described below with reference to examples: Example 1 (1) Dissolve 0.3g of sodium hydroxide in 30mL of deionized water and stir until completely dissolved. Then slowly add it to 50mL of 25% tetrapropylammonium hydroxide solution and stir at a constant speed for 30min; then add 1.5g of sodium aluminate nonahydrate and stir until completely dissolved and the solution becomes clear. Then slowly add 20g of silica in batches, keeping it evenly dispersed in the mixture. After mixing evenly, add the remaining deionized water and stir at high speed for 3-4h until a uniform, particle-free viscous gel is formed.

[0045] (2) Take the mixture from (1) and place it in a reactor. Precrystallize it at 85-95℃ for 5 hours. Then, crystallize the precrystallized colloid at 170℃ for 24 hours with a filling degree of 60%-70%. Wash the obtained product with deionized water 4-5 times until neutral, and then transfer it to 110℃ to dry for 12 hours. Then place the dried product in a furnace and slowly heat it to 550℃ at a rate of 1-2℃ / min in an air atmosphere to remove the template agent and obtain ZSM-5 zeolite molecular sieve raw powder.

[0046] (3) Take the zeolite molecular sieve raw powder obtained in (2), and put it into a mixer with 3.25g of boehmite and 0.6g of hydroxypropyl methylcellulose. Dry mix for 5-8 minutes, then spray with 2-3g of dilute nitric acid solution while stirring to initially form a moist powder. Add 5.5g of deionized water to the moist powder and stir and knead for 15-20 minutes until the material forms a plastic body that can be easily rolled into strips.

[0047] (4) The plastic material from (3) is filled into a twin-screw extruder, and 1.0 mm and 1.5 mm dies are installed respectively. The extrusion is carried out at a low speed under a pressure of 1.0-2.0 MPa. The material is then cut into uniform short rods of 5-10 mm in length by a pelletizer that operates synchronously. The short rods are then heated in a muffle furnace at constant temperatures of 80℃, 120℃, 330℃, and 550℃ for 2 hours, 2 hours, 3 hours, and 4 hours respectively. After calcination, the material is allowed to cool naturally to room temperature to obtain rod-shaped zeolite molecular sieves.

[0048] Example 2 (1) Accurately weigh 4g ammonium bicarbonate, 9.5g copper sulfate, 2.1g copper chloride and 1.63g basic zinc carbonate, add them to 100ml ammonia solution in a constant temperature water bath at 50~55℃, and stir evenly until there are no solid particles.

[0049] (2) In the above solution, add 2.2g potassium carbonate, 6.4g ammonium bicarbonate, 0.2g silver nitrate and 1g potassium bicarbonate, and stir at a constant temperature of 50~55℃ for 15~30min to finally form a uniform and stable blue impregnation solution.

[0050] (3) Take 100g of porous activated carbon and heat it in an oven at 60~70℃ for 15min.

[0051] (4) Take 60% of the impregnation liquid in step (2) and add ammonia water to adjust it to 1.1 times the mass of activated carbon to obtain a primary spray impregnation solution. Then, use a spraying device to evenly spray the primary spray impregnation solution onto the porous activated carbon to be modified to obtain primary spray activated carbon.

[0052] (5) The activated carbon sprayed once in step (4) is left to stand in the open at 50~55℃ for 3 hours, and then the residual ammonia water in the activated carbon is removed by a blower dryer. Then the dried activated carbon sprayed once is placed in an activation furnace, heated to 120℃ for 45 minutes, and then heated to 150℃ for 30 minutes. The activated carbon is obtained.

[0053] (6) Take the remaining 40% volume fraction of the impregnation solution from step (2), add ammonia water to adjust it to 1.05 times the mass of the primary activated impregnated carbon, and obtain the secondary spray impregnation solution. Then, use a spraying device to evenly spray the secondary spray impregnation solution onto the primary activated impregnated carbon to obtain secondary spray activated carbon.

[0054] (7) The activated carbon sprayed in step (6) is left to stand in the open at 50~55℃ for 2 hours, and then the residual ammonia water in the activated carbon is removed by a blower dryer. Then the dried secondary sprayed impregnated carbon is placed in an activation furnace, heated to 120℃ for 30 minutes, and then heated to 160℃ for 40 minutes to obtain secondary activated impregnated carbon.

[0055] (8) Weigh 1.1g of dipotassium hydrogen phosphate and 2.6g of zirconium nitrate and slowly add them to 75mL of pure water-ethanol mixed solution (volume ratio 2:1). Maintain heating at 55~60℃ and stir evenly with a stirrer until a stable impregnation solution is formed.

[0056] (9) The impregnated carbon that has completed the second activation is heated to 60°C again. The impregnation liquid prepared in (8) is heated and sprayed evenly onto the activated carbon. After keeping it warm and standing for a period of time, the impregnation liquid is fully absorbed and then transferred to the activation equipment for the third activation. The activated carbon is activated at 180°C for 90 minutes. After the anti-gradient aging treatment, the impregnated activated carbon material is obtained.

[0057] Example 3 (1) The activated carbon in step (9) of Example 2 is activated three times and then subjected to anti-aging with triethylenediamine. The mass of triethylenediamine added is 2% to obtain impregnated activated carbon material, which is used as carbon adsorption layer.

[0058] A layered filling strategy was adopted, and the specific filling conditions were as follows: the material was divided into two layers: a carbon adsorption layer and a molecular sieve adsorption layer (the rod-shaped zeolite molecular sieve material prepared in Example 1). The upper layer was the carbon adsorption layer and the lower layer was the molecular sieve adsorption layer, with a filling mass ratio of 1:1.5.

[0059] (2) The impregnated activated carbon material in (1) above should meet the requirement that 60% of the particle size range is 1.0 to 1.5 mm, and the rod-shaped zeolite molecular sieve material has a particle size distribution of 1.0 mm to 1.5 mm.

[0060] Example 4 (1) The activated carbon in step (9) of Example 2 was activated three times and then subjected to anti-aging with triethylenediamine in two different ways. The mass of triethylenediamine added was 6% to obtain impregnated activated carbon material, which was used as a water-absorbing layer. The mass of triethylenediamine added was 2% to obtain impregnated activated carbon material, which was used as a carbon adsorption layer.

[0061] A layered filling strategy was adopted, and the specific filling conditions were as follows: the material was divided into three layers: a water-absorbing layer, a carbon adsorption layer, and a molecular sieve adsorption layer (the rod-shaped zeolite molecular sieve material prepared in Example 1). The bottom layer was a molecular sieve layer, the middle layer was a carbon adsorption layer, and the top layer was a water-absorbing layer. The filling mass ratio was 1:4:3.

[0062] (2) The impregnated activated carbon materials in (1) above should all meet the requirement that the particle size range of 1.0 to 1.5 mm accounts for 60%, and the rod-shaped zeolite molecular sieve materials have a particle size distribution of 1.0 mm to 1.5 mm.

[0063] Example 5 (1) The activated carbon in step (9) of Example 2 was activated three times and then subjected to anti-aging with triethylenediamine in two different ways. The mass of triethylenediamine added was 4% to obtain impregnated activated carbon material, which was used as a water-absorbing layer. The mass of triethylenediamine added was 2% to obtain impregnated activated carbon material, which was used as a carbon adsorption layer.

[0064] A layered filling strategy was adopted, and the specific filling conditions were as follows: the material was divided into three layers: a water-absorbing layer, a carbon adsorption layer, and a molecular sieve adsorption layer (the rod-shaped zeolite molecular sieve material prepared in Example 1). The bottom layer was a molecular sieve layer, the middle layer was a carbon adsorption layer, and the top layer was a water-absorbing layer. The filling mass ratio was 1:4:3.

[0065] (2) The impregnated activated carbon materials in (1) above should all meet the requirement that the particle size range of 1.0 to 1.5 mm accounts for 60%, and the rod-shaped zeolite molecular sieve materials have a particle size distribution of 1.0 mm to 1.5 mm.

[0066] Example 6 (1) The activated carbon in step (9) of Example 2 was activated three times and then subjected to anti-aging treatment with triethylenediamine in two different ways. The mass of triethylenediamine added was 6% to obtain impregnated activated carbon material, which was used as a water-absorbing layer. The mass of triethylenediamine added was 3% to obtain impregnated activated carbon material, which was used as carbon adsorption layer one. The mass of triethylenediamine added was 2% to obtain impregnated activated carbon material, which was used as carbon adsorption layer two.

[0067] A layered filling strategy was adopted, and the specific filling conditions were as follows: the material was divided into three layers: a water-absorbing layer, a carbon adsorption layer one, a carbon adsorption layer two, and a molecular sieve adsorption layer (the rod-shaped zeolite molecular sieve material prepared in Example 1). The bottom layer was a molecular sieve layer, the middle layer was a carbon adsorption layer, and the top layer was a water-absorbing layer. The filling mass ratio was 1:2:2:3.

[0068] (2) The impregnated activated carbon materials in (1) above should all meet the requirement that the particle size range of 1.0 to 1.5 mm accounts for 60%, and the rod-shaped zeolite molecular sieve materials have a particle size distribution of 1.0 mm to 1.5 mm.

[0069] Example 7 The raw materials were the same as in Example 3, except that a mixing and filling strategy was adopted, and a double cone mixer was used to mix them thoroughly. The mass ratio of the carbon adsorption layer to the molecular sieve adsorption layer was 1.5:1.

[0070] The samples from Examples 1-7 were subjected to EO and CNCl protection time tests. Simultaneously, the relative humidity of the mixed airflow at the carbon layer inlet and outlet was measured to evaluate the impact of a high-humidity environment on the overall protective performance of the composite bed. The EO and CNCl protection time test conditions were: total bed height 78 mm, relative humidity of the mixed airflow 80% (using a fixed value), and airflow specific velocity 0.70 L / min·cm. 2 The power tube diameter was 20 mm; the initial concentration of cyanogen chloride was 9.0 mg / L, and the test standard was GJB 6239.16-2008; the initial concentration of ethylene oxide was 1.0 mg / L, the permeation concentration was 5 ppm, and the penetration endpoint was determined by gas chromatography.

[0071] Table 1 Comparison of the performance of cyanogen chloride and ethylene oxide in samples.

[0072] Based on Examples 1 and 2, the combined protective capabilities of impregnated carbon and molecular sieve beds against cyanide chloride and ethylene oxide are both low, making it difficult to meet the current demand for comprehensive and efficient protection in chemical protection equipment.

[0073] By comparing Example 1, Example 2, and Example 3, the composite-filled impregnated carbon and molecular sieve layer can effectively improve the material's comprehensive balanced protection performance against EO and CNCl.

[0074] By comparing Examples 3 and 4, it is clear that the absence of an absorbent layer will result in excessively high humidity in the airflow, which will affect the absorption efficiency of ethylene oxide.

[0075] By comparing Examples 3, 4, and 7, compared to layered packing, simple physical mixing packing will cause a "short circuit" phenomenon in the protection of ethylene oxide and cyanide chloride, failing to fully utilize the material's intended performance.

[0076] By comparing Examples 1-7, it can be seen that, with the filling height remaining constant, the composite bed using a layered filling strategy significantly improves the overall protective performance against EO and CNCl in high humidity environments, effectively enhancing the material's humidity adaptability and protection level, and providing a reliable basis for the design and application of protective equipment.

[0077] As shown in Table 1, the composite material bed prepared in this invention possesses excellent comprehensive protection performance against EO and CNCl while maintaining high humidity. It meets the Class III protection requirements of GJB 7943-2012 and has a good safety factor. Simple impregnated carbon or molecular sieve composite beds offer relatively low comprehensive protection performance against EO and CNCl, making it difficult to meet the protection requirements for highly polar EO molecules under high humidity conditions. In this invention, the impregnated carbon constructs an LB acid synergistic interface by loading multiple impregnating components. Multiple impregnation loading and gradient calcination techniques are used to regulate the spatial gradient distribution of different active components in the activated carbon channels. Anti-aging treatment enhances the impregnation water absorption capacity, thereby achieving basic protection against EO and CNCl under high humidity. Furthermore, the hydrophobicity of the molecular sieve is controlled by adjusting the Si / Al ratio, and columnar molecular sieves of specific particle sizes are prepared by extrusion calcination, exhibiting good EO protection performance under high humidity conditions. This invention employs a layered filling strategy of impregnated carbon and molecular sieve composite beds. The impregnated activated carbon utilizes its highly developed hierarchical porosity to pre-enrich and hydrolyze some EO and CNCl small molecules. This, combined with the molecular sieve layer, further adsorbs and hydrolyzes EO small molecules. The impregnated carbon layer effectively reduces the inhibitory effect of high humidity on EO hydrolysis, thus achieving highly efficient comprehensive protection against polar small molecules like EO and CNCl. This material preparation and application strategy is simple and provides a new pathway for efficient and broad-spectrum protection against multiple pollutants, showing promising application prospects in the field of chemical protective equipment.

[0078] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The embodiments and features described in these embodiments can be arbitrarily combined without conflict. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A method for preparing an adsorbent material for protecting against ethylene oxide and cyanide chloride, characterized in that, The method includes the following steps: (1) Weigh out soluble copper salt and soluble zinc salt, slowly add them to the ammonia solution, heat and stir until uniform, then add ammonium bicarbonate and silver nitrate, adjust the alkalinity of the impregnation solution and add soluble potassium salt until a stable dark blue metal complex impregnation solution is formed (verify whether the raw materials in this step match the example). (2) Spray the above impregnation solution into a reaction vessel containing activated carbon at a certain temperature, keep it warm and let it stand for a certain time, and then heat it up to activate it. (3) Weigh out soluble phosphate and soluble zirconium salt and slowly add them to the pure water-ethanol mixed solution. Maintain a certain temperature and heat until the solution is uniformly stirred to form a stable impregnation solution. (4) The impregnated carbon that has been activated twice is heated again. The impregnation liquid prepared in step (3) is heated and sprayed evenly onto the activated carbon. After being kept warm and standing for a period of time, it is heated and activated. After being subjected to anti-gradient aging treatment, the impregnated activated carbon material is obtained. (5) After mixing silicon source, aluminum source, nano source, template agent and deionized water to form a sol, the sol is subjected to pre-crystallization, static crystallization, separation, washing, drying and calcination to remove the template agent, and ZSM-5 zeolite molecular sieve raw powder is obtained. (6) The raw zeolite molecular sieve powder is mixed with boehmite binder, guar gum powder, dilute acid solution and deionized water to form a plastic body. After extrusion molding, it is dried and baked to obtain ZSM-5 zeolite molecular sieve. (7) The ZSM-5 zeolite molecular sieve was combined with the prepared activated impregnated carbon for filling to obtain an adsorbent material for protecting against ethylene oxide and cyanide chloride.

2. The method for preparing the adsorbent material for protecting against ethylene oxide and cyanide chloride according to claim 1, characterized in that, In the steps described above, the soluble copper salt is copper sulfate, copper chloride, or basic copper carbonate. Soluble zinc salts are zinc carbonate or basic zinc carbonate; Soluble potassium salts include potassium carbonate and potassium hydroxide; Soluble phosphates are dipotassium hydrogen phosphate, ammonium dihydrogen phosphate, or ammonium phosphate; Soluble zirconium salts are zirconium nitrate or zirconium chloride.

3. The method for preparing the adsorbent material for protecting against ethylene oxide and cyanide chloride according to claim 1, characterized in that, In step (2), the impregnation liquid is divided into two parts. The first part of the impregnation liquid is sprayed into the reactor containing activated carbon. After keeping it warm and letting it stand for a certain time, it is heated and activated. Then the second part of the impregnation liquid is sprayed into the reactor containing activated carbon. After keeping it warm and letting it stand for a certain time, it is heated and activated.

4. The method for preparing the adsorbent material for protecting against ethylene oxide and cyanide chloride according to claim 1, characterized in that, The volume fraction of the first impregnation solution is 50-60%; the volume fraction of the second impregnation solution is 40-50%.

5. The method for preparing the adsorbent material for protecting against ethylene oxide and cyanide chloride according to claim 4, characterized in that, The first impregnation solution also includes ammonia water with a mass fraction of 40-50%, and the ammonia water is added to make up to 110-120% of the mass of activated carbon. The second impregnation solution also includes ammonia water with a mass fraction of 60-65%, which is added to make up to 100-105% of the activated carbon mass.

6. The method for preparing the adsorbent material for protecting against ethylene oxide and cyanide chloride according to claim 1, characterized in that, The activation temperature is 120~180℃, and the activation time is 1~2h.

7. The method for preparing the adsorbent material for protecting against ethylene oxide and cyanide chloride according to claim 1, characterized in that, In step (3), the impregnation solution for the second impregnation is 70% to 80% of the mass of activated carbon, and the impregnation solution contains phosphorus and zirconium. The anti-aging agent used in step (4) of the anti-gradient aging process is triethylenediamine, and the addition amount is 2% to 6%; The tiered anti-aging process of the anti-aging agent involves adding the anti-aging agent in stages of 0.5-2% to achieve at least 3-6 anti-aging processes.

8. The method for preparing the adsorbent material for protecting against ethylene oxide and cyanide chloride according to claim 1, characterized in that, In step (5), the silicon source is selected from one or more of silica sol, water glass, white carbon black or tetraethyl orthosilicate, preferably industrial grade silica sol; The aluminum source is selected from aluminum sulfate, sodium aluminate, boehmite, or metallic aluminum, preferably aluminum sulfate or sodium aluminate; the sodium source is selected from sodium hydroxide, sodium aluminate, or water glass; the template agent is tetrapropylammonium hydroxide or hexamethyleneimine. The molar ratio of the silicon source, aluminum source, nano source and template agent is in the range of 1 : (0.01~0.04) : (0.01~0.03) : (0.1~0.4) : (15~40), with a preferred silicon-to-aluminum ratio of 40~80. The pre-crystallization temperature is 80~140℃, and the time is 1~8h; The static crystallization temperature is 170~180℃, and the time is 12-36h.

9. The method for preparing the adsorbent material for protecting against ethylene oxide and cyanide chloride according to claim 1, characterized in that, In step (6), the drying operation is to dry in an oven at 110~120℃ for 6~12h; the calcination operation is to dry at a constant temperature of 550~600℃ for 4~6h.

10. The method for preparing an adsorbent material for protecting against ethylene oxide and cyanide chloride according to claim 1 or 7, characterized in that, In step (7), when the amount of anti-aging agent added to the activated impregnated charcoal is 3% or more, it forms a water-absorbing layer; when it is less than 3%, it forms a charcoal adsorption layer. The water-absorbing layer, carbon adsorption layer, and ZSM-5 zeolite molecular sieve are loaded in a mass ratio of 1:(4~6):(1.5~4.5) from top to bottom.

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