Anesthetic gas adsorbent, anesthetic gas adsorption filter, inhalation anesthesia system, and anesthetic gas removal method

Abstract

The anesthetic gas adsorbent has activated carbon. The volume of pores having a pore radius of 0.6 nm or less in the activated carbon as calculated by the MP method is 0.41 mL / g or more. The ratio of the "pore volume having a pore radius of 0.4 nm or less" in the activated carbon calculated by the MP method to the "pore volume having a pore radius of 0.5 nm or less" in the activated carbon calculated by the MP method is 50% or more.

Description

Technical Field

[0001] This invention relates to an anesthetic gas adsorbent, an anesthetic gas adsorption filter, an inhalation anesthesia system, and a method for removing anesthetic gases. Background Technology

[0002] Previously, there were methods known for contacting residual anesthetic gas containing volatile anesthetic agents with an adsorbent to adsorb and remove the volatile anesthetic agents from the residual anesthetic gas (see, for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2002-172171 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] In the adsorbent described in Patent Document 1, there is a requirement to further improve the performance of adsorbing volatile anesthetics.

[0008] This invention provides an anesthetic gas adsorbent, an anesthetic gas adsorption filter, an inhalation anesthesia system, and a method for removing anesthetic gases that can improve the adsorption performance of anesthetic gases in waste gas.

[0009] Technical solutions for solving technical problems

[0010] The first aspect of the present invention includes an anesthetic gas adsorbent comprising activated carbon, wherein the pore volume of the activated carbon having a pore radius of 0.6 nm or less, as calculated by the MP method, is 0.41 mL / g or more, and the proportion of the pore volume of the activated carbon having a pore radius of 0.5 nm or less, as calculated by the MP method, to the pore volume of the activated carbon having a pore radius of 0.4 nm or less, as calculated by the MP method, is 50% or more.

[0011] The second aspect of the invention includes the anesthetic gas adsorbent of the first aspect, wherein the packing density of the activated carbon after deducting the calcination residue is greater than 0.38 g / mL and less than 0.50 g / mL.

[0012] The third aspect of the present invention includes the anesthetic gas adsorbent of the first or second aspect, wherein the activated carbon has a pore volume of less than 1.70 mL / g with a pore radius of less than 0.6 nm as calculated by the MP method.

[0013] The fourth aspect of the present invention includes an anesthetic gas adsorbent according to any one of the first to third aspects, wherein the activated carbon has a specific surface area of ​​950 m². 2 / g or more and 2000m2 The activated carbon has a butane adsorption capacity of 24.4% or more and 40.0% or less per g.

[0014] The fifth aspect of the present invention is an anesthetic gas adsorption filter comprising the anesthetic gas adsorbent of any one of the first to fourth aspects.

[0015] A sixth aspect of the present invention includes the anesthetic gas adsorption filter of the fifth aspect, comprising a container, the anesthetic gas adsorbent, and a spacer. The container has an inlet and an outlet. The inlet is arranged in a first direction at one end of the container for waste gas containing anesthetic gas to flow into the container. The outlet is arranged in the first direction at the other end of the container for waste gas from which the anesthetic gas has been removed to flow out of the container. The anesthetic gas adsorbent is arranged in the first direction between the inlet and the outlet. The spacer is arranged in the first direction between the inlet and the anesthetic gas adsorbent.

[0016] The seventh aspect of the invention includes the anesthetic gas adsorption filter of the sixth aspect, wherein the spacer is a protrusion extending from the inner surface of one side of the container in the first direction toward the anesthetic gas adsorbent.

[0017] The eighth aspect of the invention includes an inhalation anesthesia system comprising a vaporizer and an anesthetic gas adsorption filter, the vaporizer vaporizing a volatile anesthetic agent to generate an anesthetic gas and supplying the generated anesthetic gas to inhaled gas from a ventilator, the anesthetic gas adsorption filter being connected to the exhaust line of the ventilator and having an anesthetic gas adsorbent of any one of the first to fourth aspects.

[0018] The ninth aspect of the present invention includes the inhalation anesthesia system of the eighth aspect, and also includes the artificial respirator.

[0019] The tenth aspect of the present invention includes a method for removing anesthetic gases, wherein waste gas containing anesthetic gases is passed through an anesthetic gas adsorbent of any one of the first to fourth aspects to remove the anesthetic gases from the waste gas.

[0020] The effects of the invention

[0021] The anesthetic gas adsorbent according to the present invention comprises activated carbon having a pore volume of 0.41 mL / g or more with a pore radius of 0.6 nm or less, and a ratio of pore volume of 0.4 nm or less to pore volume of 0.5 nm or less of 50% or more.

[0022] Therefore, it can improve the adsorption performance of anesthetic gases in exhaust gas.

[0023] The anesthetic gas adsorption filter, inhalation anesthesia system, and method for removing anesthetic gases of the present invention use the anesthetic gas adsorbent.

[0024] Therefore, it can efficiently remove anesthetic gases from exhaust gases. Attached Figure Description

[0025] Figure 1 This is an explanatory diagram illustrating the activation process in the manufacturing method of an anesthetic gas adsorbent.

[0026] Figure 2 This is a cross-sectional view illustrating one embodiment of the anesthetic gas adsorption filter of the present invention.

[0027] Figure 3 This is a structural diagram illustrating one embodiment of the inhalation anesthesia system of the present invention.

[0028] Figure 4 This is a cross-sectional view of the anesthetic gas adsorption filter of variant example (2).

[0029] Figure 5 This is a cross-sectional view of the anesthetic gas adsorption filter of variant example (3).

[0030] Figure 6A yes Figure 5 The diagram shows a three-dimensional representation of the lid. Figure 6B Viewed from the inside Figure 6A The diagram shows the plan of the cover.

[0031] Figure 7A This is a cross-sectional view of the anesthetic gas adsorption filter shown in variant example (4). Figure 7B Viewed from the other side of the first direction Figure 7A The diagram shows the cover.

[0032] Figure 8 This is an explanatory diagram of the cover used to illustrate the modified example (5).

[0033] Figure 9 This is an explanatory diagram of the cover used to illustrate the modified example (6).

[0034] Figure 10 This is an explanatory diagram of the cover used to illustrate the modified example (7). Detailed Implementation

[0035] 1. Anesthetic gas adsorbent

[0036] An anesthetic gas adsorbent, which is one embodiment of the present invention, will be described.

[0037] An anesthetic gas adsorbent is used in the anesthetic gas adsorption filter 10 of the inhalation anesthesia system 100 (see reference). Figure 2The anesthetic gas adsorption filter 10 and the inhalation anesthesia system 100 will be described later. The anesthetic gas adsorbent includes activated carbon. The anesthetic gas adsorbent may consist solely of activated carbon. Activated carbon is capable of adsorbing anesthetic gases. Examples of activated carbon include wood-based activated carbon, coconut-based activated carbon, and coal-based activated carbon. Coconut-based activated carbon and coal-based activated carbon are preferred, and coconut-based activated carbon is more preferred.

[0038] (1) Details of activated carbon

[0039] The pore volume of activated carbon calculated by the MP method is, for example, 0.43 mL / g to 0.70 mL / g, preferably 0.48 mL / g to 0.66 mL / g.

[0040] The pore volume with a pore radius of 0.6 nm or less in the activated carbon, calculated by the MP method, is 0.41 mL / g or more, preferably 0.43 mL / g or more, and more preferably 0.44 mL / g or more. If the pore volume with a pore radius of 0.6 nm or less in the activated carbon, calculated by the MP method, is at or above the lower limit, the adsorption performance (adsorption capacity) of anesthetic gases in waste gas can be improved.

[0041] It should be noted that twice the "pore radius" of activated carbon calculated by the MP method is equivalent to the "pore diameter" of activated carbon calculated by the MP method. Therefore, for example, the "pore volume with a pore radius of 0.6 nm or less" in activated carbon calculated by the MP method is equivalent to the "pore volume with a pore diameter of 1.2 nm or less" in activated carbon calculated by the MP method. Therefore, in this specification, the "pore volume with a pore radius of 0.6 nm or less" in activated carbon calculated by the MP method can be replaced with the "pore volume with a pore diameter of 1.2 nm or less" in activated carbon calculated by the MP method, the "pore volume with a pore radius of 0.5 nm or less" in activated carbon calculated by the MP method can be replaced with the "pore volume with a pore diameter of 1.0 nm or less" in activated carbon calculated by the MP method, and the "pore volume with a pore radius of 0.4 nm or less" in activated carbon calculated by the MP method can be replaced with the "pore volume with a pore diameter of 0.8 nm or less" in activated carbon calculated by the MP method.

[0042] There is no upper limit to the "pore volume with a pore radius of 0.6 nm or less" in activated carbon calculated by the MP method. For example, the "pore volume with a pore radius of 0.6 nm or less" in activated carbon calculated by the MP method is 1.70 mL / g or less, preferably 1.20 mL / g or less, and more preferably 0.70 mL / g or less. If the "pore volume with a pore radius of 0.6 nm or less" in activated carbon calculated by the MP method is below the aforementioned upper limit, it is possible to prevent the anesthetic gas adsorbent from becoming excessively porous. This, in turn, can prevent the enlargement of anesthetic gas adsorption filters.

[0043] The range of "pore volume with a pore radius of less than 0.6 nm" in activated carbon calculated by the MP method is, for example, 0.41 mL / g to 1.70 mL / g, preferably 0.43 mL / g to 1.20 mL / g, and more preferably 0.44 mL / g to 0.70 mL / g.

[0044] The "pore volume with a pore radius of less than 0.6 nm" is measured by the method described in the examples described later.

[0045] Compared to the pore volume V of activated carbon with a pore radius of less than 0.5 nm calculated by the MP method 0.5 The pore volume V of activated carbon with a pore radius of less than 0.4 nm, calculated using the MP method. 0.4 The proportion of "V" 0.4 / V 0.5 The percentage is over 50%. Specifically, the proportion (V) 0.4 / V 0.5 () is "the pore volume V with a pore radius of less than 0.4 nm". 0.4 "Compared to "pore volume V with a pore radius of less than 0.5 nm" 0.5 The percentage of “” is calculated using the following formula.

[0046] Formula: Proportion (V) 0.4 / V 0.5 ) = (Volume of pores with a pore radius of less than 0.4 nm) 0.4 / Pore volume V with a pore radius of less than 0.5 nm 0.5 )×100, "pore volume V with a pore radius of less than 0.5 nm 0.5 "and "pore volume V with a pore radius of less than 0.4 nm 0.4 "Measurement is performed using the methods described in the embodiments described later."

[0047] If the ratio (V) 0.4 / V 0.5 If the value is above the lower limit, the adsorption performance (adsorption capacity) of anesthetic gases in waste gas can be further improved.

[0048] Ratio (V) 0.4 / V 0.5 For example, it is 99% or less, preferably 91% or less, more preferably 89% or less, and even more preferably 87% or less. If the proportion (V) 0.4 / V 0.5 If the value is below the upper limit, the proportion of pores with a pore radius of 0.4 nm or more and 0.5 nm or less can be ensured, thus ensuring the movement path of anesthetic gas molecules to pores with a pore radius of 0.4 nm or less. As a result, the reduction in adsorption performance can be suppressed.

[0049] Ratio (V) 0.4 / V 0.5 For example, it is 50% to 99%, preferably 50% to 91%, more preferably 50% to 89%, and even more preferably 50% to 87%.

[0050] The packing density of activated carbon is, for example, 0.40 g / mL to 0.50 g / mL.

[0051] The packing density of activated carbon was measured using the method described in the examples described later.

[0052] Activated carbon contains carbon and calcination residue. Activated carbon can also contain no components other than carbon and calcination residue. In other words, activated carbon can consist solely of carbon and calcination residue.

[0053] The carbon component of activated carbon can adsorb anesthetic gases. The packing density of the carbon component is calculated by subtracting the ignition residue from the packing density of the activated carbon. Specifically, the packing density of the carbon component is calculated using the following formula.

[0054] Formula: Carbon packing density = Activated carbon packing density × [1 - (residue on ignition / 100)], where the activated carbon packing density after subtracting the residue on ignition (carbon packing density) exceeds 0.38 g / mL and is less than 0.50 g / mL. Preferably, the carbon packing density is 0.39 g / mL or higher. If the carbon packing density exceeds the lower limit, the volume of carbon relative to the volume of activated carbon can be ensured. If the carbon packing density is less than the upper limit, the pore volume of activated carbon can be ensured. Therefore, if the carbon packing density is within the specified range, improved adsorption performance can be achieved.

[0055] The calcination residue of activated carbon does not contribute to the adsorption of anesthetic gases. The composition of the calcination residue of activated carbon is, for example, 1.0% to 15.0% by mass, preferably 1.0% to 5.0% by mass.

[0056] The ignition residue of activated carbon was measured using the methods described in the examples described later.

[0057] In addition, the specific surface area of ​​activated carbon is, for example, 950 m². 2 / g or more, preferably 1050m 2 / g or more. If the specific surface area of ​​the activated carbon is above the lower limit, sufficient adsorption performance can be ensured. There is no upper limit to the specific surface area of ​​the activated carbon. The specific surface area of ​​the activated carbon can be 2000 m². 2 Below / g, it can also be 1700m 2 / g or less.

[0058] The specific surface area of ​​activated carbon can range from 950 m². 2 / g~2000m 2 / g, or 1050m 2 / g~1700m 2 / g.

[0059] Specific surface area is measured using the methods described in the examples described later.

[0060] Furthermore, the butane adsorption performance of activated carbon is, for example, 24.4% or more, preferably 25.0% or more. If the butane adsorption performance of activated carbon is above the aforementioned lower limit, sufficient adsorption performance can be ensured. There is no upper limit to the butane adsorption performance of activated carbon. The butane adsorption performance of activated carbon can be 40.0% or less, or 35.0% or less.

[0061] The butane adsorption capacity of activated carbon can range from 24.4% to 40.0% or from 25.0% to 35.0%.

[0062] (2) Details of the anesthetic gas

[0063] The anesthetic gas adsorbent is preferably used to adsorb the anesthetic gas shown in the following general formula (1).

[0064] General formula (1):

[0065] [Chemical Formula 1]

[0066]

[0067] (X is a hydrogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom, or perfluoromethyl. n is 0 or an integer from 1 to 3.)

[0068] Examples of anesthetic gases represented by the general formula (1) include isoflurane, desflurane, and sevoflurane.

[0069] In detail, in the general formula (1), where X is a chlorine atom and n is 2, the anesthetic gas is isoflurane (molecular weight: 184.5, boiling point: 48.5℃, vapor pressure at 20℃: 31.7kPa).

[0070] In the general formula (1), when X is perfluoromethyl and n is 1, the anesthetic gas is sevoflurane (molecular weight: 200.6, boiling point: 58.5℃, vapor pressure at 20℃: 20.9kPa).

[0071] In the general formula (1), when X is a fluorine atom and n is 2, the anesthetic gas is desflurane (molecular weight: 168.4, boiling point: 23.5℃, vapor pressure at 20℃: 88.5kPa).

[0072] 2. Methods for manufacturing activated carbon

[0073] Next, the manufacturing method of the anesthetic gas adsorbent will be explained.

[0074] In the manufacture of anesthetic gas adsorbents, activated carbon is first produced. Examples of methods for manufacturing activated carbon include thermal decomposition, activation, coating, and vapor deposition. Activation is the preferred method for manufacturing activated carbon.

[0075] The activation method includes an activation step. The activation method may also include a carbonization step and a removal step.

[0076] (1) Carbonization process

[0077] The carbonization process carbonizes the raw materials for activated carbon. It should be noted that if the raw material for activated carbon is coal, the manufacturing method may not include a carbonization process.

[0078] Examples of raw materials for activated carbon include plant-based materials, fossil-based materials, synthetic resins, synthetic rubber, synthetic wood, and synthetic slurries. Examples of plant-based raw materials include wood, wood flour, fruit shells, seeds, byproducts of slurry production, bagasse, and molasses waste. Examples of fruit shells include coconut shells. Examples of seeds include palm kernels, plum seeds, and peach seeds. Examples of fossil-based raw materials include coal, anthracite, petroleum distillation residues, petroleum pitch, coke, and coal tar. Examples of synthetic resins include phenolic resins, vinyl chloride resins, vinyl acetate resins, melamine resins, urea resins, resorcinol resins, celluloid, epoxy resins, polyurethane resins, polyester resins, acrylic resins, and polyamide resins. Examples of synthetic rubbers include polybutene, polybutadiene, and polychloroprene. One or more raw materials can be used alone or in combination.

[0079] Plant-based and fossil-based raw materials are preferred as raw materials for activated carbon, and coconut shells and coal are more preferred.

[0080] There are no limitations on the heating conditions in the carbonization process. In the carbonization process, heating is carried out, for example, in an oxygen-free environment, at 300°C to 900°C, preferably 400°C to 800°C.

[0081] There is no limit to the heating time in the carbonization process. The heating time is, for example, 15 minutes to 20 hours, preferably 30 minutes to 10 hours.

[0082] The carbonization process can be performed under reduced pressure or in a nitrogen atmosphere. For example, a rotary kiln can be used to perform the carbonization process.

[0083] It should be noted that, in the carbonization process, the raw materials can also be crushed or shaped before carbonization.

[0084] When the raw material is pulverized, the particle size of the raw material (50% of the particle size in the cumulative distribution based on volume, D50) is, for example, 1 μm to 150 μm.

[0085] Alternatively, the carbonized raw material (carbonized raw material) can be pulverized during the carbonization process. When the carbonized raw material is pulverized, the particle size (50% particle size in the cumulative distribution based on volume, D50) of the carbonized raw material is, for example, 1 μm to 150 μm.

[0086] Alternatively, during the carbonization process, after the raw materials (or carbonization raw materials) are pulverized, additives can be added to the pulverized raw materials (or carbonization raw materials) as needed for mixing, and the resulting mixture can be shaped. This allows for the easy manufacture of the activated carbon.

[0087] Examples of additives include water, coal tar, anhydrous tar, hard pitch, coal tar-based pitch, and petroleum pitch. Additives can be used alone or in combination with two or more.

[0088] The additive is added in the range of 1.0 to 100.0 parts by weight, preferably 1.0 to 50.0 parts by weight, relative to 100 parts by weight of the raw material (or carbonized raw material).

[0089] When the compound is shaped into a cylindrical shape, the diameter of the shaped part is preferably 0.1 mm to 4.0 mm or less. In addition, the aspect ratio (height / diameter) of the shaped part is, for example, 1 to 10.

[0090] (2) Removal process

[0091] The removal process is performed after the carbonization process and before the activation process. In the removal process, the causative substances of the ignition residue (such as soil and sand) are removed from the carbonization raw materials.

[0092] Methods for removing causative substances from carbonized feedstocks include, for example, wet or dry soil-sand separation and heavy liquid beneficiation using high-density liquids.

[0093] (3) Activation process

[0094] like Figure 1 As shown, in the activation process, activation system 1 is used to activate the carbonized raw material C after the causative substances have been removed.

[0095] The activation system 1 includes an activation furnace 2, a supply device 3, a conveying device 4, and an activation gas supply device 5. The activation system 1 is continuous. Specifically, the activation system 1 continuously supplies carbonization raw material C to the activation furnace 2, and continuously removes activated carbon A from the activation furnace 2 after activation.

[0096] (3-1) Activation furnace

[0097] The activation furnace 2 extends along the flow direction of the carbonization raw material C. The activation furnace 2 is cylindrical. The activation furnace 2 has an inlet 2A and an outlet 2B. The inlet 2A is arranged at the upstream end of the activation furnace 2 in the flow direction. The outlet 2B is arranged at the downstream end of the activation furnace 2 in the flow direction.

[0098] There is no limitation to the method for raising the temperature inside the activation furnace 2. Examples of methods for raising the temperature inside the activation furnace 2 include heating the activation furnace 2 from the outside using an electric heater, burning fuel inside the activation furnace 2, and burning combustible gases such as hydrogen and carbon monoxide produced in the activation reaction. Preferably, the method of burning fuel inside the activation furnace 2 is preferred. More preferably, the method of burning fuel at the inlet 2A side of the activation furnace 2 is preferred. By burning fuel at the inlet 2A side of the activation furnace 2, the temperature of the carbonization raw material supplied from inlet 2A and the activation gas supplied by the activation gas supply device 5 can be rapidly increased, enabling rapid activation of the carbonization raw material supplied from inlet 2A.

[0099] The temperature at the inlet 2A side of the activation furnace 2 is, for example, 750°C or higher, preferably 850°C or higher, and more preferably 870°C or higher. If the temperature at the inlet 2A side of the activation furnace 2 is below the aforementioned lower limit, the carbonization raw material can be sufficiently activated within the activation furnace 2. As a result, the carbon content of the obtained activated carbon can be adjusted to the aforementioned range.

[0100] The temperature inside the activation furnace 2 is, for example, below 1200°C, preferably below 1100°C, and more preferably below 1000°C. If the temperature inside the activation furnace 2 is below the upper limit value, it is possible to suppress the high density of the obtained activated carbon and adjust the filling density of the carbon component of the obtained activated carbon to the range mentioned above.

[0101] The activation time is not limited as long as the activated carbon can be obtained. The activation time is, for example, 1 hour to 120 hours, preferably 4 hours to 72 hours.

[0102] It should be noted that the adsorption performance of the obtained activated carbon (e.g., butane adsorption performance) can also be measured, and the temperature on the inlet 2A side of the activation furnace 2 can be adjusted to obtain the desired adsorption performance.

[0103] Examples of activation furnaces 2 include rotary kilns and belt kilns. Rotary kilns are preferred as activation furnace 2.

[0104] (3-2) Supply device

[0105] The supply device 3 supplies carbonization raw material C to the inlet 2A of the activation furnace 2. Examples of the supply device 3 include belt conveyors and screw feeders.

[0106] (3-3) Conveying device

[0107] The conveying device 4 conveys activated carbon A discharged from outlet 2B of the activation furnace 2. The conveying device 4 can be either batch-type or continuous. The activated carbon A is at a high temperature immediately after being discharged from outlet 2B. Therefore, to suppress combustion of the activated carbon A, it is preferable to reduce the oxygen concentration within the conveying device 4. Methods for reducing the oxygen concentration within the conveying device 4 include, for example, introducing an inert gas such as nitrogen into the conveying device 4, or introducing exhaust gas from the rotary kiln into the conveying device 4. The conveying device 4 preferably includes a cooling device for cooling the activated carbon A. The cooling device can be air-cooled or water-cooled.

[0108] (3-4) Activation gas supply device

[0109] The activation gas supply device 5 introduces activation gas from the inlet 2A side inside the activation furnace 2. In other words, the activation gas supply device 5 introduces activation gas from the upstream end of the activation furnace 2 in the flow direction.

[0110] Therefore, the concentration of the activation gas in the activation furnace 2 is highest at the inlet 2A side and decreases as it approaches the outlet 2B. Consequently, the reaction rate between the carbonization raw material C and the activation gas is fastest at the inlet 2A side and decreases as it approaches the outlet 2B.

[0111] Therefore, the carbonized raw material C supplied to the activation furnace 2 reacts with a high concentration of activation gas, forming pores with small pore radii on the surface of the carbonized raw material C. Then, as the carbonized raw material C moves towards the outlet 2B within the activation furnace 2, the concentration of the activation gas decreases, and the reaction rate between the carbonized raw material C and the activation gas decreases. Therefore, it is possible to suppress the expansion of pores on the surface of the carbonized raw material C due to further activation reactions. As a result, it is possible to suppress the reduction and proportion (V) of pores with pore radii below 0.6 nm. 0.4 / V 0.5 The decrease of ).

[0112] Examples of activating gases include water vapor and carbon dioxide. Water vapor is preferred. Using water vapor as the activating gas increases the pore volume for pores with a pore radius of 0.6 nm or less. Therefore, activated carbon A with excellent adsorption properties for anesthetic gases can be obtained. It should be noted that inert gases such as nitrogen or air can also be used in conjunction with the activating gas.

[0113] The concentration of the activating gas is not limited as long as the activated carbon can be obtained. The concentration of the activating gas at the inlet 2A side is, for example, 10% to 100% by volume, preferably 20% to 80% by volume.

[0114] It should be noted that the activation process can be performed under reduced pressure or under a nitrogen atmosphere.

[0115] Alternatively, the obtained activated carbon can be crushed, pulverized, and graded. It can also be washed with water, organic solvents, acidic aqueous solutions, or alkaline aqueous solutions. Furthermore, the obtained activated carbon can be subjected to additional heat treatment.

[0116] 3. Anesthetic gas adsorption filter

[0117] The anesthetic gas adsorbent is suitable for the anesthetic gas adsorption filter 10. The anesthetic gas adsorption filter 10 is used for the exhaust gas treatment of the inhalation anesthesia system 100. Figure 2 As shown, the anesthetic gas adsorption filter 10 includes a container 11 and an anesthetic gas adsorbent 12.

[0118] Container 11 houses the anesthetic gas adsorbent 12. Container 11 extends along a first direction. The shape and material of container 11 are not limited. Container 11 may be cylindrical, for example. Container 11 may be made of rigid plastic, for example. Container 11 has an inlet 11A and an outlet 11B. Inlet 11A is arranged at one end of container 11 in the first direction. The shape of inlet 11A is not limited. Inlet 11A may be circular, for example. The size of inlet 11A is smaller than the internal size of container 11. More specifically, the diameter R1 of inlet 11A is smaller than the inner diameter R2 of container 11. Outlet 11B is arranged at the other end of container 11 in the first direction. The arrangement, number, and shape of outlets 11B are not limited. There may be one or more outlets 11B. Waste gas G1 containing anesthetic gas flows into inlet 11A. Waste gas G1 entering container 11 from inlet 11A passes through the anesthetic gas adsorbent 12. At this point, the anesthetic gas in the exhaust gas G1 is adsorbed by the activated carbon of the anesthetic gas adsorbent 12 and removed from the exhaust gas G1. In other words, the anesthetic gas adsorption filter 10 passes the exhaust gas G1 containing anesthetic gas through the anesthetic gas adsorbent 12 to remove the anesthetic gas from the exhaust gas G1. The exhaust gas G2, from which the anesthetic gas has been removed, flows out from the outlet 11B.

[0119] Container 11 may have: a container body 111 having an opening 111A; and a lid 112 closing the opening 111A. The container body 111 extends along a first direction. The container body 111 is cylindrical. The opening 111A is arranged at one end of the container body 111 in the first direction. The diameter of the opening 111A is the same as the inner diameter R2 of the container 11. In the assembly of the anesthetic gas adsorption filter 10, the anesthetic gas adsorbent 12 is arranged inside the container body 111 via the opening 111A. The container body 111 may have an outlet 11B. The lid 112 may have an inlet 11A. The lid 112 may be a lid that can be removed from the container body 111.

[0120] An anesthetic gas adsorbent 12 is disposed within a container 11. The anesthetic gas adsorbent 12 fills the container 11. The anesthetic gas adsorbent 12 is disposed within the container 11 between an inlet 11A and an outlet 11B. The anesthetic gas adsorbent 12 is disposed in a first direction between an inlet 11A and an outlet 11B.

[0121] 4. Inhalation anesthesia system

[0122] like Figure 3 As shown, the inhalation anesthesia system 100 includes a vaporizer 102 and an anesthetic gas adsorption filter 10. The inhalation anesthesia system 100 may also include a ventilator 101.

[0123] Vaporizer 102 is connected to the inhalation tubing 103 and the expiration tubing 104 of ventilator 101. Vaporizer 102 vaporizes a volatile anesthetic supplied by an anesthetic supply tubing (not shown) to generate anesthetic gas. Vaporizer 102 supplies the generated anesthetic gas to the inhaled air from ventilator 101. The inhaled air containing the anesthetic gas is supplied to the patient through flexible tubing 106.

[0124] An anesthetic gas adsorption filter 10 is connected to the exhaust pipe 105 of the respirator 101. The exhaust gas G1 from the respirator 101 (refer to...) Figure 2 The exhaust gas contains anesthetic gases present in the patient's exhalation. As described above, the anesthetic gas adsorption filter 10 removes the anesthetic gases from the exhaust gas G1.

[0125] 5. Functions and Effects

[0126] (1) According to the anesthetic gas adsorbent, the pore volume with a pore radius of 0.6 nm or less is 0.41 mL / g or more, and the ratio of the pore volume with a pore radius of 0.4 nm or less to the pore volume with a pore radius of 0.5 nm or less (V 0.4 / V 0.5 The activated carbon content is over 50%.

[0127] Therefore, it can improve the adsorption performance of anesthetic gases in exhaust gas.

[0128] (2) According to the manufacturing method of the anesthetic gas adsorbent, such as Figure 1 As shown, in the activation process, activated carbon A is manufactured continuously (the carbonization raw material C is continuously supplied to the activation furnace 2, and the activated carbon A activated in the activation furnace 2 is continuously removed from the activation furnace 2). The concentration of the activation gas in the activation furnace 2 is highest at the inlet 2A side of the activation furnace 2 and decreases as it approaches the outlet 2B of the activation furnace 2.

[0129] Therefore, near the inlet 2A, the carbonization raw material C supplied to the activation furnace 2 reacts with a high concentration of activation gas, forming pores with small pore radii on the surface of the carbonization raw material C.

[0130] Then, as the carbonization raw material C moves toward outlet 2B within the activation furnace 2, the concentration of the activation gas decreases.

[0131] Therefore, it can inhibit the expansion of pores on the surface of carbonized raw material C due to further activation reactions.

[0132] As a result, it is possible to suppress the reduction of pores with a pore radius of less than 0.6 nm and the proportion (V) 0.4 / V 0.5 The reduction of ) enables the efficient production of the anesthetic gas adsorbent.

[0133] (3) such as Figure 2 As shown, the anesthetic gas adsorption filter 10 includes the anesthetic gas adsorbent 12.

[0134] Therefore, it can efficiently remove anesthetic gases from exhaust gas G1.

[0135] (4) such as Figure 3 As shown, the inhalation anesthesia system 100 includes the anesthetic gas adsorption filter 10. Therefore, it can efficiently remove anesthetic gases from the exhaust gas G1.

[0136] 6. Variations

[0137] The following describes modified examples. In the modified examples, the same symbols are used to mark the same parts as in the described embodiment, and their descriptions are omitted.

[0138] (1) The anesthetic gas adsorbent may also have a bag for holding activated carbon. The bag may be made of, for example, a breathable non-woven fabric.

[0139] (2) such as Figure 4 As shown, the anesthetic gas adsorption filter 10 may further include buffer components 13A and 13B and a dust filter 14. In this case, the anesthetic gas adsorbent 12 is filled between the buffer components 13A and 13B in a first direction. In the assembly of the anesthetic gas adsorption filter 10, the dust filter 14, the buffer component 13B, the anesthetic gas adsorbent 12, and the buffer component 13A are arranged sequentially within the container body 111 through the opening 111A.

[0140] A buffer member 13A is arranged between the inlet 11A and the anesthetic gas adsorbent 12 in the direction in which the container 11 extends (first direction). The buffer member 13A is also arranged between the cover 112 and the anesthetic gas adsorbent 12 in the direction in which the container 11 extends (first direction). The buffer member 13A is formed, for example, of a breathable nonwoven fabric or a breathable polyurethane foam. The buffer member 13A is in contact with the anesthetic gas adsorbent 12. The buffer member 13A inhibits the movement of the anesthetic gas adsorbent 12 within the container 11. Additionally, the buffer member 13A inhibits the displacement of the anesthetic gas adsorbent 12 within the container 11. Furthermore, the buffer member 13A inhibits the overflow of the anesthetic gas adsorbent 12 from the inlet 11A.

[0141] The thickness of the buffer component 13A is, for example, 5 mm to 30 mm, preferably 10 mm to 25 mm.

[0142] A buffer component 13B is arranged between the outlet 11B and the anesthetic gas adsorbent 12 in the direction in which the container 11 extends (first direction). The buffer component 13B is formed, for example, of a breathable nonwoven fabric or a breathable polyurethane foam. The buffer component 13B is in contact with the anesthetic gas adsorbent 12. Together with the buffer component 13A, the buffer component 13B inhibits the movement of the anesthetic gas adsorbent 12 within the container 11. Furthermore, together with the buffer component 13A, the buffer component 13B inhibits the displacement of the anesthetic gas adsorbent 12 within the container 11. Additionally, the buffer component 13A inhibits the overflow of the anesthetic gas adsorbent 12 from the outlet 11B.

[0143] The thickness of the buffer component 13B is, for example, 5mm to 30mm, preferably 10mm to 25mm.

[0144] Dust filter 14 is arranged between outlet 11B and buffer member 13B. Dust filter 14 is made of, for example, breathable nonwoven fabric. Dust filter 14 captures fine powder of activated carbon that has passed through buffer member 13B. The mesh size of dust filter 14 is higher than that of buffer members 13A and 13B.

[0145] The thickness of the dust filter 14 is thinner than the thickness of the buffer member 13B. The thickness of the dust filter 14 is, for example, 0.1 mm to 1.0 mm, preferably 0.2 mm to 0.5 mm.

[0146] (3) such as Figure 5 As shown, the anesthetic gas adsorption filter 10 may further include spacers 15. The anesthetic gas adsorption filter 10 may include multiple spacers 15.

[0147] A spacer 15 is arranged between the cap 112 and the buffer member 13A in the direction in which the container 11 extends (a first direction). The spacer 15 is also arranged in the first direction between the inlet 11A and the anesthetic gas adsorbent 12. The spacer 15 is in contact with the buffer member 13A. The spacer 15 separates the buffer member 13A from the inlet 11A, ensuring space between the inlet 11A and the buffer member 13A. Thus, the spacer 15 ensures space between the inlet 11A and the anesthetic gas adsorbent 12.

[0148] like Figure 6A As shown, the spacer 15 protrudes from the inner surface S1 of the cover 112 in the first direction toward the buffer member 13A. In other words, the spacer 15 protrudes from the inner surface S1 of the cover 112 in the first direction toward the anesthetic gas absorbent 12. Alternatively, the spacer 15 protrudes from the inner surface S1 of one side of the container 11 in the first direction toward the anesthetic gas absorbent 12. The spacer 15 is a protrusion. Figure 6BAs shown, spacers 15 are arranged around the inlet 11A. Multiple spacers 15 are arranged circumferentially around the inlet 11A. The multiple spacers 15 are spaced apart from each other circumferentially around the inlet 11A. The spacers 15 extend radially along the inlet 11A. The shape and number of spacers 15 are not limited.

[0149] According to this modified example, a portion of the exhaust gas G1 entering the container 11 from the inlet 11A can flow radially along the container 11 within the space between the inlet 11A and the buffer member 13A.

[0150] Therefore, the exhaust gas G1 entering the container 11 from the inlet 11A can act on the entire anesthetic gas adsorbent 12 inside the container 11.

[0151] As a result, it is able to efficiently remove anesthetic gases from exhaust gas G1.

[0152] In addition, according to this modified example, the spacer 15 protrudes from the inner surface S1 of the cover 112 in the first direction.

[0153] Therefore, the spacer 15 and the cover 112 can be processed together.

[0154] As a result, by installing the cover 112 onto the container body 111, the cover 112 can be installed onto the container body 111, and the spacer 15 can be arranged inside the container 11.

[0155] Alternatively, the spacer 15 can be discarded along with the cover 112.

[0156] (4) such as Figure 7A As shown, the anesthetic gas adsorption filter 10 may also include a second spacer 21.

[0157] The second spacer 21 is arranged in a second direction (specifically, the radial direction of the inlet 11A) orthogonal to the first direction between the inner surface S2 of the container 11 and the spacers 15. The second spacer 21, together with the plurality of spacers 15, ensures the space between the inlet 11A and the anesthetic gas adsorbent 12. More specifically, the second spacer 21 is arranged in the first direction between the cover 112 and the buffer member 13A. The second spacer 21 protrudes from the inner surface S1 of the cover 112 toward the buffer member 13A in the first direction. The second spacer 21 contacts the peripheral edge E of the buffer member 13A. The second spacer 21 presses against the peripheral edge E of the buffer member 13A. Thus, in the radial direction of the container 11, closer to the inner surface S2 of the container 11 than the plurality of spacers 15, the spacer 21 can be used to ensure the space between the inlet 11A and the buffer member 13A.

[0158] like Figure 7B As shown, the second spacer 21 is annular. The second spacer 21 extends along the inner surface S2 of the container 11 in the second direction (refer to...). Figure 7A This extends the range. As a result, leakage of exhaust gas G1 into container 11 from the gap between container body 111 and cover 112 can be suppressed.

[0159] (5) such as Figure 8 As shown, multiple spacers 15 can also extend circumferentially along the inlet 11A.

[0160] (6) For example Figure 9 As shown, the multiple spacers 15 can also be cylindrical.

[0161] (7) For example Figure 10 As shown, multiple spacers 15 can also be continuous with the second spacer 21. Additionally, the second spacer 21 can also have multiple slits 21A. The multiple slits 21A are arranged spaced apart from each other in the circumferential direction of the inlet 11A.

[0162] (8) In the variations (1) to (7), the same function and effect as the described implementation can also be obtained.

[0163] [Example]

[0164] The following embodiments are provided to illustrate the present invention in more detail, but the present invention is not limited to these embodiments. The specific numerical values ​​of addition ratios (including ratios), physical property values, parameters, etc., used in the following description can be replaced with the corresponding upper limit values ​​(defined as "below" or "less than") or lower limit values ​​(defined as "above" or "exceeding") of the addition ratios (including ratios), physical property values, parameters, etc., described in the "Specific Embodiments" section. It should be noted that unless otherwise specified, "parts" and "%" are based on mass.

[0165] 1. Manufacturing of Activated Carbon

[0166] (1) Example 1

[0167] As raw materials for carbonization, we prepared carbonized coconut shells from Sri Lanka.

[0168] Next, a soil and sand separator is used to remove soil and sand (the substance that causes the burning residue) from the carbonized raw material (removal process).

[0169] Next, a rotary kiln is used as an activation furnace to activate the carbonized raw material after the soil and sand have been removed. Specifically, the carbonized raw material after the soil and sand have been removed is continuously fed into the rotary kiln, and the activated carbon after activation in the rotary kiln is continuously removed from the rotary kiln.

[0170] By burning heavy oil on the inlet side of the rotary kiln, the inlet temperature of the rotary kiln is adjusted to 900℃~1000℃.

[0171] In addition, water vapor, used as an activating gas, is introduced through an inlet pipe inserted into the inlet side of the rotary kiln, so that the concentration of the activating gas at the inlet side is 20% to 70% by volume. The length of the inlet pipe inserted into the rotary kiln is 2.5% of the total length of the rotary kiln.

[0172] Next, the obtained activated carbon is cooled and crushed to obtain activated carbon used as an adsorbent for anesthetic gases.

[0173] (2) Example 2

[0174] Except that the amount of carbonization raw material supplied was changed to 1.1 times that of Example 1, activated carbon was obtained in the same manner as in Example 1.

[0175] (3) Example 3

[0176] Except that the amount of carbonization raw material supplied was changed to 1.2 times that of Example 1, activated carbon was obtained in the same manner as in Example 1.

[0177] (4) Example 4

[0178] Except that the amount of carbonization raw material supplied was changed to 1.3 times that of Example 1, activated carbon was obtained in the same manner as in Example 1.

[0179] (5) Example 5

[0180] Activated carbon was obtained in the same manner as in Example 1, except that deashed Chinese coal pellets were used as the carbonization raw material.

[0181] (6) Example 6

[0182] Used coconut shell granular activated carbon (4×6 mesh) is prepared as a carbonization raw material.

[0183] The carbonized raw materials were washed with water to remove soil and sand in the same manner as in Example 1.

[0184] Next, activated carbon was obtained in the same manner as in Example 1, except that the fuel was changed to methane.

[0185] (7) Comparative Example 1

[0186] Except that the amount of carbonization raw material supplied was changed to 1.5 times that of Example 1, activated carbon was obtained in the same manner as in Example 1.

[0187] (8) Comparative Example 2

[0188] Activated carbon was obtained in the same manner as in Example 1, except that deashed Colombian coal pellets were used as the carbonization raw material.

[0189] (9) Comparative Example 3

[0190] Except that the amount of carbonization raw material supplied was changed to 1.1 times that of Comparative Example 2, activated carbon was obtained in the same manner as in Comparative Example 2.

[0191] (9) Comparative Example 4

[0192] Except that the amount of carbonization raw material supplied was changed to 1.2 of that in Comparative Example 2, activated carbon was obtained in the same manner as in Comparative Example 2.

[0193] 2. Physical property measurement of activated carbon

[0194] (1) Pore volume and specific surface area

[0195] The activated carbon obtained in each embodiment and comparative example was heated at 150°C for 2 hours under vacuum.

[0196] Next, the amount of nitrogen adsorption was measured at -196°C using an automatic specific surface area / pore distribution measuring device (Micromeritics (Shimazu) TRISTAR3000 model), and nitrogen adsorption isotherms were constructed.

[0197] The nitrogen adsorption isotherms obtained were analyzed using the MP method (Micropore method) to calculate the pore volume (more specifically, the cumulative pore volume of pore radii below 0.6 nm), the pore volume (more specifically, the cumulative pore volume of pore radii below 0.4 nm), the pore volume (more specifically, the cumulative pore volume of pore radii below 0.5 nm), and the ratio (V). 0.4 / V 0.5 The results are shown in Table 1.

[0198] In addition, the specific surface area per 1g of activated carbon was calculated using nitrogen adsorption isotherms and the BET multipoint method based on a straight line in the region with a relative pressure of 0.01 to 0.10. The results are shown in Table 1.

[0199] (2) Filling density of carbon components

[0200] The packing density of the activated carbon obtained in each example and each comparative example was measured using the method specified in Japanese Industrial Standard JIS K1474:2014.

[0201] In detail, the activated carbon obtained in each example and comparative example was dried at 115±5°C for 3 hours using a constant temperature desiccator (DVS402, manufactured by Yamato Scientific Co., Ltd.).

[0202] Next, the activated carbon removed from the constant temperature dryer is naturally cooled to room temperature in a dryer using silica gel as a desiccant.

[0203] Next, the naturally cooled activated carbon is introduced into the storage funnel of the filling density measuring container (TD-V5, manufactured by Toyo Machine Manufacturing Co., Ltd). Using the attached vibrator, it is filled into a 100mL graduated cylinder to the 100mL mark.

[0204] Measure the mass of activated carbon in the graduated cylinder and calculate the packing density of the activated carbon.

[0205] In addition, the ignition residue of the activated carbon obtained in each example and each comparative example was measured using the method specified in Japanese Industrial Standard JISK1474:2014.

[0206] In detail, the activated carbon obtained in each example and comparative example was dried at 115±5°C for 3 hours using a constant temperature desiccator (DVS402, manufactured by Yamato Scientific Co., Ltd.).

[0207] Next, the activated carbon removed from the constant temperature dryer is naturally cooled to room temperature in a dryer using silica gel as a desiccant.

[0208] After measuring the mass of the activated carbon after natural cooling, the activated carbon was ignited in air at 850±50℃ for 1 hour using an electric furnace (Yamato Scientific Co., Ltd., FO811 (model)).

[0209] Next, the obtained ash was naturally cooled to room temperature in a dryer using silica gel as a desiccant, and its mass (mass of ash content) was measured to calculate the residue upon ignition.

[0210] Next, the carbon packing density was calculated using the formula described in the embodiment. The results are shown in Table 1.

[0211] (3) Butane adsorption performance

[0212] The butane adsorption performance of the activated carbons obtained in each example and comparative example was measured using the method specified in ASTM D5742.

[0213] In detail, first, the glass tube as specified in ASTM D5742 is dried and its weight (A) is measured.

[0214] Next, the packing density of the activated carbon, which had been dried in advance according to the method specified in ASTM D2854, was measured using the method specified in ASTM D2867.

[0215] Next, weigh activated carbon equivalent to a volume of 16.70 ± 0.05 mL calculated based on the measured filling density, fill the glass tube, and measure the total weight (B).

[0216] Next, the glass tube was immersed in a water bath at 25±0.2℃, and butane was introduced into the activated carbon inside the glass tube at a flow rate of 250±5mL / min for 900 seconds.

[0217] The glass tube was then removed from the water bath and wiped clean, and the overall weight (C) was measured.

[0218] The butane adsorption performance was calculated using the following formula. The results are shown in Table 1.

[0219] Formula: Butane adsorption performance = [(CB) / (BA)] × 100

[0220] 3. Performance evaluation of activated carbon

[0221] The activated carbon obtained in each example and comparative example was dried at 115±5°C for 3 hours using a constant temperature desiccator (DVS402, manufactured by Yamato Scientific Co., Ltd.).

[0222] Next, the activated carbon removed from the constant temperature dryer is naturally cooled to room temperature in a dryer using silica gel as a desiccant.

[0223] Weigh out an amount of activated carbon equivalent to 300 mL in volume, calculated according to the “filling density of activated carbon”, from the naturally cooled activated carbon, and fill it into the test column.

[0224] It should be noted that the test column has the following structure: an acrylic resin cylinder with an inner diameter of 50 mm is arranged between a first cap having an inlet and a second cap having an outlet. Inside the cylinder, from the first cap toward the second cap, a buffer component made of non-woven fabric, activated carbon, another buffer component made of non-woven fabric, and a dust filter made of non-woven fabric are stacked in sequence. The height of the activated carbon layer inside the cylinder (the dimension in the direction the cylinder extends) is approximately 150 mm.

[0225] Next, air containing 0.33% by mass of isoflurane at 20±3°C was introduced into the test column filled with activated carbon at a flow rate of 4.5 L / min from the inlet.

[0226] Then, the cumulative mass of isoflurane flowing into the test column during the period until the isoflurane concentration in the air flowing out of the outlet exceeds 0.15% by mass is divided by the mass of the packed activated carbon to obtain the isoflurane removal performance.

[0227] [Table 1]

[0228]

[0229] It should be noted that the invention is provided as an exemplary embodiment of the present invention, but this is merely an example and should not be interpreted as limiting. Variations of the invention that will be apparent to those skilled in the art are included within the scope of the following claims.

[0230] -Industry Applicability-

[0231] The anesthetic gas adsorbent, anesthetic gas adsorption filter, and anesthetic gas removal method of the present invention can be used for the removal of anesthetic gases. The inhalation anesthesia system of the present invention can be used for inhalation anesthesia.

[0232] -Symbol Explanation-

[0233] 10. Anesthetic gas adsorption filter

[0234] 11 Containers

[0235] 11A Inlet

[0236] 11B Outlet

[0237] 12. Anesthetic gas adsorbent

[0238] 15 spacers

[0239] G1 Exhaust gas containing anesthetic gases

[0240] G2 Exhaust gas from which anesthetic gases have been removed

[0241] 100 Inhalation Anesthesia System

[0242] 101 artificial respirators

[0243] 102 Vaporizer

[0244] 105 Exhaust Pipeline

Claims

1. An anesthetic gas adsorbent, characterized in that: It contains activated carbon, The pore volume of the activated carbon with a pore radius of less than 0.6 nm, calculated by the MP method, is greater than 0.41 mL / g; and The proportion of the pore volume with a pore radius of less than 0.4 nm in the activated carbon calculated by the MP method to the pore volume with a pore radius of less than 0.5 nm in the activated carbon calculated by the MP method is more than 50%.

2. The anesthetic gas adsorbent according to claim 1, characterized in that: The packing density of the activated carbon after deducting the calcination residue is greater than 0.38 g / mL and less than 0.50 g / mL.

3. The anesthetic gas adsorbent according to claim 1, characterized in that: The pore volume of the activated carbon with a pore radius of less than 0.6 nm, calculated by the MP method, is less than 1.70 mL / g.

4. The anesthetic gas adsorbent according to claim 1, characterized in that: The specific surface area of ​​the activated carbon is 950 m². 2 / g or more and 2000m 2 / g or less The activated carbon has a butane adsorption capacity of 24.4% or higher and 40.0% or lower.

5. An anesthetic gas adsorption filter, characterized in that: Includes the anesthetic gas adsorbent as described in claim 1.

6. The anesthetic gas adsorption filter according to claim 5, characterized in that: Includes a container, the anesthetic gas adsorbent, and a spacer; The container has an inlet and an outlet. The inlet is located at one end of the container in the first direction, allowing waste gas containing anesthetic gas to flow into the container. The outlet is arranged at the other end of the container in the first direction, allowing the waste gas from which the anesthetic gas has been removed to flow out of the container; The anesthetic gas adsorbent is arranged in the first direction between the inlet and the outlet; The spacer is arranged in the first direction between the inlet and the anesthetic gas adsorbent.

7. The anesthetic gas adsorption filter according to claim 6, characterized in that: The spacer is a protrusion that extends from the inner surface of one side of the container in the first direction toward the anesthetic gas adsorbent.

8. An inhalation anesthesia system, characterized in that: It includes a vaporizer and an anesthetic gas adsorption filter, wherein the vaporizer vaporizes a volatile anesthetic agent to produce an anesthetic gas, and supplies the produced anesthetic gas into the inhaled air from a ventilator. The anesthetic gas adsorption filter is connected to the exhaust pipe of the artificial respirator and has the anesthetic gas adsorbent as described in claim 1.

9. The inhalation anesthesia system according to claim 8, characterized in that: It also includes the artificial respirator.

10. A method for removing anesthetic gases, characterized in that: The anesthetic gas containing the exhaust gas is passed through the anesthetic gas adsorbent of claim 1 to remove the anesthetic gas from the exhaust gas.

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