Anesthetic gas adsorbent, method for manufacturing the anesthetic gas adsorbent, anesthetic gas adsorption filter, inhalation anesthesia system, and method for removing anesthetic gas

Abstract

The present invention provides an anesthetic gas adsorbent capable of improving the performance of adsorbing anesthetic gas during exhaust, a method for manufacturing the anesthetic gas adsorbent, an anesthetic gas adsorption filter, an inhalation anesthesia system, and a method for removing anesthetic gas. [Solution] The anesthetic gas adsorbent contains activated carbon. The "pore volume with a pore radius of 0.6 nm or less" calculated using the MP method is 0.41 mL / g or more. The ratio of the "pore volume with a pore radius of 0.4 nm or less" calculated using the MP method to the "pore volume with a pore radius of 0.5 nm or less" calculated using the MP method is 50% or more. The packing density of the activated carbon, excluding the ignition residue, is greater than 0.38 g / mL and less than 0.50 g / mL.

Description

[Technical Field]

[0001] The present invention relates to an anesthetic gas adsorbent, a method for producing an anesthetic gas adsorbent, an anesthetic gas adsorption filter, an inhalation anesthesia system, and a method for removing anesthetic gas. [Background technology]

[0002] BACKGROUND ART Conventionally, a method has been known in which excess anesthetic gas containing a volatile anesthetic is brought into contact with an adsorbent to adsorb and remove the volatile anesthetic in the excess anesthetic gas (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-172171 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for further improvement in the performance of adsorbents such as those described in Patent Document 1 in adsorbing volatile anesthetics.

[0005] The present invention provides an anesthetic gas adsorbent that can improve the performance of adsorbing anesthetic gas during exhaust, a method for manufacturing an anesthetic gas adsorbent, an anesthetic gas adsorption filter, an inhalation anesthesia system, and a method for removing anesthetic gas. [Means for solving the problem]

[0006] The present invention [1] comprises an anesthetic gas adsorbent having activated carbon, wherein the "pore volume with a pore radius of 0.6 nm or less" of the activated carbon calculated by the MP method is 0.41 mL / g or more, the ratio of the "pore volume with a pore radius of 0.4 nm or less" of the activated carbon calculated by the MP method to the "pore volume with a pore radius of 0.5 nm or less" of the activated carbon calculated by the MP method is 50% or more, and the packing density of the activated carbon, excluding the ignition residue, is more than 0.38 g / mL and less than 0.50 g / mL.

[0007] The present invention [2] includes the anesthetic gas adsorbent according to the above [1], wherein the activated carbon has a "pore volume with a pore radius of 0.6 nm or less" of 1.70 mL / g or less, as calculated by the MP method.

[0008] The present invention [3] is characterized in that the specific surface area of the activated carbon is 950 m 2 / g or more, 2000m 2 / g or less, and the butane adsorption capacity of the activated carbon is 24.4% or more and 40.0% or less.

[0009] The present invention [4] includes any one of the anesthetic gas adsorbents [1] to [3] above, which is used for adsorbing an anesthetic gas represented by the following general formula (1).

[0010] General formula (1):

[0011] [ka]

[0012] (X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, or a perfluoromethyl group. n is 0 or an integer of 1 to 3.)

[0013] The present invention [5] includes the anesthetic gas adsorbent according to the above [4], wherein the anesthetic gas is isoflurane, desflurane, or sevoflurane.

[0014] The present invention [6] is a method for producing an anesthetic gas adsorbent according to any one of [1] to [5] above, which includes a removal step of removing causative substances of ignition residue from a carbonized raw material, and an activation step of activating the carbonized raw material from which the causative substances have been removed to obtain activated carbon, in which the carbonized raw material is continuously supplied to an activation furnace while the activated carbon activated in the activation furnace is continuously removed from the activation furnace, and the concentration of the activation gas in the activation furnace is highest at the inlet side of the activation furnace and decreases as it approaches the outlet of the activation furnace.

[0015] The present invention [7] includes the method for producing an anesthetic gas adsorbent according to the above [6], in which an activation gas is introduced from the upstream end of the activation furnace in the direction of flow of the carbonized raw material.

[0016] The present invention [8] includes an anesthetic gas adsorption filter comprising a container having an inlet through which exhaust gas containing anesthetic gas flows in and an outlet through which the exhaust gas from which the anesthetic gas has been removed flows out, and an anesthetic gas adsorbent according to any one of [1] to [5] above, disposed between the inlet and the outlet in the container.

[0017] The present invention [9] includes an inhalation anesthesia system comprising a ventilator, a vaporizer that vaporizes a volatile anesthetic to generate the anesthetic gas and supplies the generated anesthetic gas to the inhaled air from the ventilator, and the anesthetic gas adsorption filter described above in [8] that is connected to the exhaust line of the ventilator.

[0018] The present invention

[10] includes a method for removing an anesthetic gas, which comprises passing exhaust gas containing an anesthetic gas through any one of the anesthetic gas adsorbents [1] to [5] above to remove the anesthetic gas from the exhaust gas. [Effects of the Invention]

[0019] The anesthetic gas adsorbent of the present invention contains activated carbon having a "pore volume with a pore radius of 0.6 nm or less" of 0.41 mL / g or more, a ratio of "pore volume with a pore radius of 0.4 nm or less" to "pore volume with a pore radius of 0.5 nm or less" of 50% or more, and a packing density, excluding the ignition residue, of more than 0.38 g / mL and less than 0.50 g / mL.

[0020] Therefore, the performance of adsorbing the anesthetic gas during exhaust can be improved.

[0021] According to the method for producing an anesthetic gas adsorbent of the present invention, in the activation step, activated carbon is activated continuously (a method in which the carbonization raw material is continuously supplied to an activation furnace, and the activated carbon activated in the activation furnace is continuously removed from the activation furnace). The concentration of the activation gas in the activation furnace is highest at the inlet side of the activation furnace and decreases toward the outlet of the activation furnace.

[0022] Therefore, the above-mentioned anesthetic gas adsorbent can be produced efficiently.

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

[0024] Therefore, the anesthetic gas can be efficiently removed during exhaust. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is an explanatory diagram for explaining the activation step in the method for producing an anesthetic gas adsorbent of the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing one embodiment of the anesthetic gas adsorption filter of the present invention. [Figure 3] FIG. 3 is a configuration diagram for explaining the configuration of one embodiment of the inhalation anesthesia system of the present invention. [Figure 4] FIG. 4 is a cross-sectional view of the anesthetic gas adsorption filter of the second modification. [Figure 5]FIG. 5 is a cross-sectional view of the anesthetic gas adsorption filter of the modified example (3). [Figure 6] Fig. 6A is a perspective view of the lid shown in Fig. 5. Fig. 6B is a plan view of the lid shown in Fig. 6A as seen from the inside. DETAILED DESCRIPTION OF THE INVENTION

[0026] 1. Anesthetic gas absorbent An anesthetic gas adsorbent according to one embodiment of the present invention will now be described.

[0027] The anesthetic gas adsorbent is used in the anesthetic gas adsorption filter 10 of the inhalation anesthesia system 100 (see Figure 2). The anesthetic gas adsorption filter 10 and the inhalation anesthesia system 100 will be described later. The anesthetic gas adsorbent contains 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. Preferred examples of activated carbon include coconut-based activated carbon and coal-based activated carbon, and more preferably coconut-based activated carbon.

[0028] (1) Details of activated carbon The pore volume of the activated carbon calculated by the MP method is, for example, 0.43 mL / g to 0.70 mL / g, or preferably 0.48 mL / g to 0.66 mL / g.

[0029] The "pore volume of pores with a pore radius of 0.6 nm or less" of 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. When the "pore volume of pores with a pore radius of 0.6 nm or less" of activated carbon calculated by the MP method is equal to or greater than the lower limit, the ability to adsorb anesthetic gases in the exhaust (adsorption performance) can be improved.

[0030] The upper limit of the "pore volume with a pore radius of 0.6 nm or less" of activated carbon calculated by the MP method is not limited. The "pore volume with a pore radius of 0.6 nm or less" of activated carbon calculated by the MP method is, for example, 1.70 mL / g or less, preferably 1.20 mL / g or less, and more preferably 0.70 mL / g or less. When the "pore volume with a pore radius of 0.6 nm or less" of activated carbon calculated by the MP method is equal to or less than the upper limit, the anesthetic gas adsorbent can be prevented from becoming excessively bulky. This prevents the anesthetic gas adsorption filter from becoming too large.

[0031] The range of the "pore volume having a pore radius of 0.6 nm or less" of 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.

[0032] The "pore volume with a pore radius of 0.6 nm or less" is measured by the method described in the examples below.

[0033] The pore volume V of activated carbon with a pore radius of 0.5 nm or less calculated using the MP method 0.5 ", whereas the "pore volume V of activated carbon with a pore radius of 0.4 nm or less calculated by the MP method 0.4 " percentage (V 0.4 / V 0.5 ) is 50% or more. Specifically, the ratio (V 0.4 / V 0.5 ) is the pore volume V of pores with a radius of 0.5 nm or less. 0.5 " to "pore volume V of pores with a radius of 0.4 nm or less 0.4 " and is calculated using the following formula:

[0034] Formula: Ratio(V 0.4 / V 0.5 ) = (pore volume V of pores with a radius of 0.4 nm or less 0.4 / pore volume V of pores with a radius of 0.5 nm or less 0.5 ) x 100 Pore volume V of pores with a radius of 0.5 nm or less 0.5 " and "pore volume V of pores with a radius of 0.4 nm or less 0.4" is measured by the method described in the Examples below.

[0035] Ratio (V 0.4 / V 0.5 ) is equal to or greater than the lower limit, the performance of adsorbing the anesthetic gas being discharged (adsorption performance) can be further improved.

[0036] Ratio (V 0.4 / V 0.5 ) is, for example, 99% or less, preferably 91% or less, more preferably 89% or less, more preferably 87% or less. 0.4 / V 0.5 When the pore radius is equal to or less than the upper limit, the proportion of pores with a pore radius of 0.4 nm to 0.5 nm can be ensured, and a migration path for anesthetic gas molecules to pores with a pore radius of 0.4 nm or less can be secured. As a result, a decrease in adsorption performance can be suppressed.

[0037] Ratio (V 0.4 / V 0.5 ) is, for example, 50% to 99%, preferably 50% to 91%, more preferably 50% to 89%, and more preferably 50% to 87%.

[0038] The packing density of the activated carbon is, for example, 0.40 g / mL to 0.50 g / mL.

[0039] The packing density of activated carbon is measured by the method described in the Examples below.

[0040] The activated carbon contains a carbon component and an ignition residue. The activated carbon may contain no components other than the carbon component and the ignition residue. In other words, the activated carbon may consist only of the carbon component and the ignition residue.

[0041] The carbon component of activated carbon is capable of adsorbing 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:

[0042] Formula: Packing density of carbon component = Packing density of activated carbon × [1 - (ignition residue / 100)] The packing density of the activated carbon (packing density of the carbon component) minus the ignition residue is greater than 0.38 g / mL and less than 0.50 g / mL. The packing density of the carbon component is preferably 0.39 g / mL or greater. When the packing density of the carbon component exceeds the lower limit, the volume of the carbon component relative to the volume of the activated carbon can be ensured. When the packing density of the carbon component is less than the upper limit, the pore volume of the activated carbon can be ensured. Therefore, when the packing density of the carbon component is within the above range, the adsorption performance can be improved.

[0043] The ignition residue of activated carbon does not contribute to the adsorption of anesthetic gases. The ignition residue of activated carbon is, for example, 1.0% to 15.0% by mass, or preferably 1.0% to 5.0% by mass.

[0044] The ignition residue of activated carbon is measured by the method described in the Examples below.

[0045] The specific surface area of activated carbon is, for example, 950 m 2 / g or more, preferably 1050m 2 / g or more. If the specific surface area of the activated carbon is equal to or greater than the above lower limit, sufficient adsorption performance can be ensured. There is no upper limit for the specific surface area of the activated carbon. The specific surface area of the activated carbon is 2000 m 2 / g or less, and 2 / g or less.

[0046] The specific surface area of activated carbon ranges from 950m 2 / g~2000m 2 / g, or 1050m 2 / g~1700m 2 / g.

[0047] The specific surface area is measured by the method described in the examples below.

[0048] The butane adsorption capacity of the activated carbon is, for example, 24.4% or more, preferably 25.0% or more. When the butane adsorption capacity of the activated carbon is equal to or greater than the above lower limit, sufficient adsorption capacity can be ensured. The upper limit of the butane adsorption capacity of the activated carbon is not limited. The butane adsorption capacity of the activated carbon may be 40.0% or less, or may be 35.0% or less.

[0049] The butane adsorption capacity of the activated carbon may be in the range of 24.4% to 40.0%, or 25.0% to 35.0%.

[0050] (2) Details of anesthetic gas The anesthetic gas adsorbent is preferably used to adsorb an anesthetic gas represented by the following general formula (1).

[0051] General formula (1):

[0052] [ka]

[0053] (X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, or a perfluoromethyl group. n is 0 or an integer of 1 to 3.)

[0054] Examples of the anesthetic gas represented by the above general formula (1) include isoflurane, desflurane, and sevoflurane.

[0055] Specifically, when X is a chlorine atom and n is 2 in the above general formula (1), the anesthetic gas is isoflurane (molecular weight: 184.5, boiling point: 48.5°C, vapor pressure at 20°C: 31.7 kPa).

[0056] In the above general formula (1), when X is a perfluoromethyl group and n is 1, the anesthetic gas is sevoflurane (molecular weight: 200.6, boiling point: 58.5°C, vapor pressure at 20°C: 20.9 kPa).

[0057] In the above 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°C, vapor pressure at 20°C: 88.5 kPa).

[0058] 2. Activated carbon manufacturing method Next, a method for producing the anesthetic gas adsorbent will be described.

[0059] In the production of the anesthetic gas adsorbent, activated carbon is first produced. Examples of methods for producing activated carbon include a thermal decomposition method, an activation method, a coating method, and a vapor deposition method. A preferred method for producing activated carbon is the activation method.

[0060] The activation method includes an activation step. The activation method may include a carbonization step and a removal step.

[0061] (1) Carbonization process In the carbonization step, the raw material of the activated carbon is carbonized. Note that when the raw material of the activated carbon is coal, the method for producing the activated carbon does not necessarily include the carbonization step.

[0062] Examples of raw materials for activated carbon include plant-based raw materials, fossil-based raw materials, synthetic resins, synthetic rubber, synthetic wood, and synthetic pulp. Plant-based raw materials include wood, wood flour, fruit shells, seeds, pulp manufacturing by-products, bagasse, and blackstrap molasses. Fruit shells include coconut shells. Seeds include palm kernels, plum seeds, and peach seeds. Fossil-based raw materials include coal, anthracite, petroleum distillation residues, petroleum pitch, coke, and coal tar. 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. Synthetic rubbers include polybutylene, polybutadiene, and polychloroprene. Each raw material can be used alone or in combination.

[0063] As raw materials for activated carbon, preferably, plant-based raw materials and fossil-based raw materials are used, and more preferably, coconut shells and coal are used.

[0064] The heating conditions in the carbonization step are not limited. In the carbonization step, heating is performed, for example, in an oxygen-free environment at a temperature of 300°C to 900°C, preferably 400°C to 800°C.

[0065] The heating time in the carbonization step is not limited and is, for example, 15 minutes to 20 hours, preferably 30 minutes to 10 hours.

[0066] The carbonization step may be carried out under reduced pressure or in a nitrogen atmosphere, for example, using a rotary kiln.

[0067] In the carbonization step, the raw material may be pulverized or molded before being carbonized.

[0068] When the raw material is pulverized, the particle size of the raw material (50% particle size of cumulative volume distribution, D50) is, for example, 1 μm to 150 μm.

[0069] In the carbonization step, the carbonized raw material (carbonized raw material) may be pulverized. When the carbonized raw material is pulverized, the particle size of the carbonized raw material (50% particle size of cumulative volume distribution, D50) is, for example, 1 μm to 150 μm.

[0070] In the carbonization step, the raw material (or the carbonized raw material) may be pulverized, and then, if necessary, additives may be added to the pulverized raw material (or the carbonized raw material), followed by kneading, and the resulting kneaded product may be molded. This allows the above-described activated carbon to be easily produced.

[0071] Examples of additives include water, coal tar, anhydrous tar, hard pitch, coal tar-based pitch, and petroleum pitch. The additives may be used alone or in combination of two or more.

[0072] The additive is blended in an amount of, for example, 1.0 to 100.0 parts by mass, preferably 1.0 to 50.0 parts by mass, relative to 100 parts by mass of the raw material (or carbonized raw material).

[0073] When the kneaded material is molded into a cylindrical shape, the diameter of the molded product is preferably 0.1 mm to 4.0 mm or less, and the aspect ratio (height / diameter) of the molded product is 1 to 10, for example.

[0074] (2) Removal process The removal step is carried out after the carbonization step and before the activation step. In the removal step, substances that cause ignition residue (e.g., soil and sand) are removed from the carbonized raw material.

[0075] Methods for removing the causative substances from the carbonized raw material include, for example, wet or dry soil separation and heavy medium separation using a liquid with a high specific gravity.

[0076] (3) Activation process As shown in FIG. 1, in the activation step, the carbonized raw material C from which the causative substances have been removed is activated using an activation system 1.

[0077] The activation system 1 includes an activation furnace 2, a supply device 3, a transport device 4, and an activation gas supply device 5. The activation system 1 is of a continuous type. Specifically, the activation system 1 continuously supplies the carbonization raw material C to the activation furnace 2, and continuously removes activated carbon A activated in the activation furnace 2 from the activation furnace 2.

[0078] (3-1) Activation furnace The activation furnace 2 extends in the flow direction of the carbonization raw material C. The activation furnace 2 has a cylindrical shape. The activation furnace 2 has an inlet 2A and an outlet 2B. The inlet 2A is located at the upstream end of the activation furnace 2 in the flow direction. The outlet 2B is located at the downstream end of the activation furnace 2 in the flow direction.

[0079] The method for increasing the temperature inside the activation furnace 2 is not limited. Examples of methods for increasing 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 generated during the activation reaction. A preferred method for increasing the temperature inside the activation furnace 2 is burning fuel inside the activation furnace 2. A more preferred method for increasing the temperature inside the activation furnace 2 is burning fuel on the inlet 2A side inside the activation furnace 2. By burning fuel on the inlet 2A side inside the activation furnace 2, the temperatures of the carbonization raw material supplied from the inlet 2A and the activation gas supplied by the activation gas supply device 5 can be quickly increased, and the carbonization raw material supplied from the inlet 2A can be quickly activated.

[0080] 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. When the temperature at the inlet 2A side of the activation furnace 2 is equal to or lower than the above-mentioned lower limit, the carbonization raw material can be sufficiently activated in the activation furnace 2. As a result, the packing density of the carbon component of the obtained activated carbon can be adjusted to the above-mentioned range.

[0081] The temperature inside the activation furnace 2 is, for example, 1200° C. or less, preferably 1100° C. or less, and more preferably 1000° C. or less. When the temperature inside the activation furnace 2 is equal to or less than the above upper limit, the resulting activated carbon can be prevented from becoming densified, and the packing density of the carbon component of the resulting activated carbon can be adjusted to the above range.

[0082] The activation step time is not limited as long as the above-mentioned activated carbon can be obtained, and is, for example, 1 hour to 120 hours, preferably 4 hours to 72 hours.

[0083] The adsorption performance (for example, butane adsorption performance) of the obtained activated carbon may be measured, and the temperature on the inlet 2A side in the activation furnace 2 may be adjusted so as to obtain a desired adsorption performance.

[0084] Examples of the activation furnace 2 include a rotary kiln and a conveyor kiln. Preferably, the activation furnace 2 is a rotary kiln.

[0085] (3-2) Feeding device The supply device 3 supplies the carbonization raw material C to the inlet 2A of the activation furnace 2. Examples of the supply device 3 include a belt conveyor and a screw feeder.

[0086] (3-3) Conveyor The transport device 4 transports the activated carbon A discharged from the outlet 2B of the activation furnace 2. The transport device 4 may be of a batch type or a continuous type. The activated carbon A is at a high temperature immediately after being discharged from the outlet 2B. Therefore, to prevent the activated carbon A from burning, the oxygen concentration in the transport device 4 is preferably reduced. Methods for reducing the oxygen concentration in the transport device 4 include, for example, introducing an inert gas such as nitrogen into the transport device 4, and introducing exhaust gas from a rotary kiln into the transport device 4. The transport device 4 is preferably equipped with a cooling device for cooling the activated carbon A. The cooling device may be an air-cooled type or a water-cooled type.

[0087] (3-4) Activation gas supply device The activation gas supply device 5 introduces the activation gas from the inlet 2A side of the activation furnace 2. In other words, the activation gas supply device 5 introduces the activation gas from the upstream end of the activation furnace 2 in the flow direction.

[0088] Therefore, 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 the concentration approaches the outlet 2B of the activation furnace 2. Therefore, the reaction rate between the carbonization raw material C and the activation gas is highest at the inlet 2A side of the activation furnace 2 and decreases as the concentration approaches the outlet 2B of the activation furnace 2.

[0089] Therefore, the carbonized raw material C supplied into the activation furnace 2 reacts with the high concentration of activation gas, and pores with small pore radii are formed on the surface of the carbonized raw material C. Thereafter, as the carbonized raw material C moves toward the outlet 2B in 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 prevent the pores on the surface of the carbonized raw material C from being expanded by further activation reactions. As a result, the decrease in pores with a pore radius of 0.6 nm or less and the decrease in the ratio (V 0.4 / V 0.5 ) can be suppressed.

[0090] Examples of the activation gas include water vapor and carbon dioxide. Preferably, water vapor is used as the activation gas. When the activation gas is water vapor, the "pore volume with a pore radius of 0.6 nm or less" can be increased. Therefore, activated carbon A with excellent anesthetic gas adsorption performance can be obtained. Note that an inert gas such as nitrogen or air may be used in combination with the above-mentioned activation gas.

[0091] The concentration of the activation gas is not limited as long as the above-mentioned activated carbon can be obtained. The concentration of the activation gas on the inlet 2A side is, for example, 10% by volume to 100% by volume, and preferably 20% by volume to 80% by volume.

[0092] The activation step may be carried out under reduced pressure or in a nitrogen atmosphere.

[0093] The activated carbon may be crushed, pulverized, and classified. The activated carbon may be washed with water, an organic solvent, an aqueous acid solution, or an aqueous alkali solution. The activated carbon may be subjected to an additional heat treatment.

[0094] 3. Anesthetic gas adsorption filter The anesthetic gas adsorbent described above is suitable for the anesthetic gas adsorption filter 10. The anesthetic gas adsorption filter 10 is used for exhaust treatment of an inhalation anesthesia system 100. As shown in FIG. 2 , the anesthetic gas adsorption filter 10 comprises a container 11 and an anesthetic gas adsorbent 12.

[0095] The container 11 contains the anesthetic gas adsorbent 12 described above. The shape and material of the container 11 are not limited. The container 11 has, for example, a cylindrical shape. The container 11 is made of, for example, hard plastic. The container 11 has an inlet 11A and an outlet 11B. Exhaust gas G1 containing anesthetic gas flows into the inlet 11A. The exhaust gas G1 that enters the container 11 from the inlet 11A passes through the anesthetic gas adsorbent 12. At this time, 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, removing 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.

[0096] The container 11 may have a container body 111 having an opening 111A and a lid 112 that closes 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 removable from the container body 111.

[0097] The anesthetic gas adsorbent 12 is filled in the container 11. The anesthetic gas adsorbent 12 is disposed in the container 11 between the inlet 11A and the outlet 11B.

[0098] 4. Inhalation Anesthesia System As shown in FIG. 3, the inhalation anesthesia system 100 includes an artificial respirator 101, a vaporizer 102, and the anesthetic gas adsorption filter 10 described above.

[0099] Vaporizer 102 is connected to inhalation line 103 of ventilator 101 and exhalation line 104 of ventilator 101. Vaporizer 102 vaporizes a volatile anesthetic agent supplied from an anesthetic agent supply line (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 tube 106.

[0100] The anesthetic gas adsorption filter 10 is connected to the exhaust line 105 of the ventilator 101. The exhaust G1 (see FIG. 2) from the ventilator 101 contains the anesthetic gas contained in the patient's exhaled breath. As described above, the anesthetic gas adsorption filter 10 removes the anesthetic gas from the exhaust G1.

[0101] 5. Effects (1) According to the above-mentioned anesthetic gas adsorbent, the "pore volume of pores with a pore radius of 0.6 nm or less" is 0.41 mL / g or more, and the ratio of the "pore volume of pores with a pore radius of 0.4 nm or less" to the "pore volume of pores with a pore radius of 0.5 nm or less" (V 0.4 / V 0.5 ) is 50% or more, and the packing density, excluding the ignition residue, is greater than 0.38 g / mL and less than 0.50 g / mL.

[0102] Therefore, the performance of adsorbing the anesthetic gas during exhaust can be improved.

[0103] (2) According to the above-described method for producing an anesthetic gas adsorbent, activated carbon A is produced continuously in the activation step (a method in which raw carbonization material C is continuously supplied to activation furnace 2, and activated carbon A activated in activation furnace 2 is continuously removed from activation furnace 2) as shown in Fig. 1. The concentration of activation gas in activation furnace 2 is highest at the inlet 2A side of activation furnace 2 and decreases toward outlet 2B of activation furnace 2.

[0104] Therefore, near the inlet 2A, the carbonization raw material C supplied into the activation furnace 2 reacts with the high concentration of activation gas, forming pores with small pore radii on the surface of the carbonization raw material C.

[0105] Thereafter, as the carbonization raw material C moves in the activation furnace 2 toward the outlet 2B, the concentration of the activation gas decreases.

[0106] Therefore, the pores on the surface of the carbonized raw material C can be prevented from being enlarged by a further activation reaction.

[0107] As a result, the decrease in pores with a pore radius of 0.6 nm or less and the ratio (V 0.4 / V 0.5 ) can be suppressed, and the above-mentioned anesthetic gas adsorbent can be produced efficiently.

[0108] (3) As shown in FIG. 2, the anesthetic gas adsorption filter 10 includes the anesthetic gas adsorbent 12 described above.

[0109] Therefore, the anesthetic gas in the exhaust gas G1 can be efficiently removed.

[0110] (4) As shown in Figure 3, the inhalation anesthesia system 100 is equipped with the above-mentioned anesthetic gas adsorption filter 10. Therefore, the anesthetic gas in the exhaust gas G1 can be efficiently removed.

[0111] 6. Variations Modifications will be described below. In the modifications, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0112] (1) The anesthetic gas adsorbent may further include a bag containing activated carbon. The bag may be made of, for example, breathable nonwoven fabric.

[0113] (2) As shown in FIG. 4, the anesthetic gas adsorption filter 10 may further include buffer members 13A and 13B and a dust filter 14.

[0114] The buffer member 13A is disposed between the inlet 11A and the anesthetic gas adsorbent 12 in the extension direction of the container 11. The buffer member 13A is disposed between the lid 112 and the anesthetic gas adsorbent 12 in the extension direction of the container 11. The buffer member 13A is made of, for example, a breathable nonwoven fabric. The buffer member 13A comes into contact with the anesthetic gas adsorbent 12. The buffer member 13A prevents the anesthetic gas adsorbent 12 from moving within the container 11. The buffer member 13A also prevents the anesthetic gas adsorbent 12 from becoming unevenly distributed within the container 11. The buffer member 13A also prevents the anesthetic gas adsorbent 12 from spilling out of the inlet 11A.

[0115] The cushioning member 13A has a thickness of, for example, 5 mm to 30 mm, or preferably 10 mm to 25 mm.

[0116] The buffer member 13B is disposed between the outlet 11B and the anesthetic gas adsorbent 12 in the extension direction of the container 11. The buffer member 13B is made of, for example, a breathable nonwoven fabric. The buffer member 13B comes into contact with the anesthetic gas adsorbent 12. Together with the buffer member 13A, the buffer member 13B prevents the anesthetic gas adsorbent 12 from moving within the container 11. Additionally, together with the buffer member 13A, the buffer member 13B prevents the anesthetic gas adsorbent 12 from becoming unevenly distributed within the container 11. Additionally, the buffer member 13A prevents the anesthetic gas adsorbent 12 from spilling from the outlet 11B.

[0117] The cushioning member 13B has a thickness of, for example, 5 mm to 30 mm, or preferably 10 mm to 25 mm.

[0118] The dust filter 14 is disposed between the outlet 11B and the buffer member 13B. The dust filter 14 is made of, for example, a breathable nonwoven fabric. The dust filter 14 captures fine activated carbon powder that has passed through the buffer member 13B. The mesh count of the dust filter 14 is higher than the mesh counts of the buffer members 13A and 13B.

[0119] The thickness of the dust filter 14 is thinner than the thickness of the buffer member 13 B. The thickness of the dust filter 14 is in the range of, for example, 0.1 mm to 1.0 mm, or preferably 0.2 mm to 0.5 mm.

[0120] (3) As shown in FIG. 5, the anesthetic gas adsorption filter 10 may further include a spacer 15.

[0121] Spacer 15 is disposed between lid 112 and buffer member 13A in the extension direction of container 11. Spacer 15 separates buffer member 13A from inlet 11A to ensure a space between inlet 11A and buffer member 13A.

[0122] As shown in FIG. 6A, the spacer 15 protrudes from the inner surface of the lid 112 toward the buffer member 13A. The spacer 15 is a protrusion. As shown in FIG. 6B, the spacer 15 is disposed around the inlet 11A. The spacer 15 extends in the radial direction of the inlet 11A. The shape and number of the spacer 15 are not limited.

[0123] According to this modification, a portion of the exhaust gas G1 that has entered the container 11 from the inlet 11A can be made to flow in the radial direction of the container 11 within the space between the inlet 11A and the buffer member 13A.

[0124] Therefore, the exhaust gas G1 that has entered the container 11 from the inlet 11A can be made to act on the entire anesthetic gas adsorbent 12 inside the container 11.

[0125] As a result, the anesthetic gas in the exhaust gas G1 can be efficiently removed.

[0126] (4) In the modified examples (1) to (3), the same effects as those of the above-described embodiment can be obtained. [Example]

[0127] The present invention will be described in more detail below with reference to examples, but is not limited thereto. Specific numerical values of the blending ratios (content ratios), physical property values, parameters, etc. used in the following description can be replaced with the upper limit values (numeric values defined as "not more than" or "less than") or lower limit values (numeric values defined as "not less than" or "exceeding") of the corresponding blending ratios (content ratios), physical property values, parameters, etc. described in the above "Form for Carrying Out the Invention." Note that "parts" and "%" are based on mass unless otherwise specified.

[0128] 1. Activated carbon production (1) Example 1 Carbonized coconut shells from Sri Lanka were prepared as the carbonization raw material.

[0129] Next, a soil separator was used to remove soil (substances that cause ignition residue) from the carbonized raw material (removal step).

[0130] Next, the carbonized raw material from which the soil and sand had been removed was activated using a rotary kiln as an activation furnace. Specifically, the carbonized raw material from which the soil and sand had been removed was continuously fed into the rotary kiln, and activated carbon activated in the rotary kiln was continuously removed from the rotary kiln.

[0131] The inlet temperature of the rotary kiln was adjusted to 900°C to 1000°C by burning heavy oil at the inlet side of the rotary kiln.

[0132] Steam as an activating gas was introduced through an introduction pipe inserted into the inlet of the rotary kiln so that the concentration of the activating gas at the inlet was 20% to 70% by volume. The length of the introduction pipe inserted into the rotary kiln was 2.5% of the total length of the rotary kiln.

[0133] Next, the obtained activated carbon was cooled and then crushed to obtain activated carbon as an anesthetic gas adsorbent.

[0134] (2) Example 2 Activated carbon was obtained in the same manner as in Example 1, except that the amount of the carbonization raw material supplied was changed to 1.1 times that of Example 1.

[0135] (3) Example 3 Activated carbon was obtained in the same manner as in Example 1, except that the amount of the carbonization raw material supplied was changed to 1.2 times that of Example 1.

[0136] (4) Example 4 Activated carbon was obtained in the same manner as in Example 1, except that the amount of the carbonization raw material supplied was changed to 1.3 times that of Example 1.

[0137] (5) Example 5 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.

[0138] (6) Example 6 Used coconut shell pellet activated carbon (4x6 mesh) was prepared as the carbonization raw material.

[0139] The carbonized raw material was washed with water to remove soil and sand in the same manner as in Example 1.

[0140] Next, activated carbon was obtained in the same manner as in Example 1, except that the fuel was changed to methane.

[0141] (7) Comparative Example 1 Activated carbon was obtained in the same manner as in Example 1, except that the amount of the carbonization raw material supplied was changed to 1.5 times that of Example 1.

[0142] (8) Comparative Example 2 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.

[0143] (9) Comparative Example 3 Activated carbon was obtained in the same manner as in Comparative Example 2, except that the amount of the carbonization raw material supplied was changed to 1.1 times that of Comparative Example 2.

[0144] (9) Comparative Example 4 Activated carbon was obtained in the same manner as in Comparative Example 2, except that the amount of the carbonization raw material supplied was changed to 1.2 times that of Comparative Example 2.

[0145] 2. Measurement of activated carbon properties (1) Pore volume and specific surface area The activated carbon obtained in each of the Examples and Comparative Examples was heated at 150° C. for 2 hours under vacuum conditions.

[0146] Next, the amount of nitrogen adsorption was measured under conditions of -196°C using an automatic specific surface area / pore distribution analyzer (Shimadzu Micromeritic, TRISTAR3000 model), and a nitrogen adsorption isotherm was created.

[0147] The obtained nitrogen adsorption isotherm was analyzed by the MP method (micropore method) to determine the pore volume with a pore radius of 0.6 nm or less (more specifically, the cumulative pore volume with a pore radius of 0.2 nm to 0.6 nm), the pore volume with a pore radius of 0.4 nm or less (more specifically, the cumulative pore volume with a pore radius of 0.2 nm to 0.4 nm), the pore volume with a pore radius of 0.5 nm or less (more specifically, the cumulative pore volume with a pore radius of 0.2 nm to 0.5 nm), and the ratio (V 0.4 / V 0.5 The results are shown in Table 1.

[0148] Furthermore, the specific surface area per 1 g of activated carbon was calculated from the straight line in the relative pressure range of 0.01 to 0.10 by the BET multipoint method using the nitrogen adsorption isotherm. The results are shown in Table 1.

[0149] (2) Packing density of carbon components The packing density of the activated carbon obtained in each example and each comparative example was measured by the method specified in JIS K1474:2014.

[0150] Specifically, the activated carbon obtained in each of the Examples and Comparative Examples was dried at 115±5° C. for 3 hours using a constant temperature dryer (DVS402, manufactured by Yamato Scientific Co., Ltd.).

[0151] Next, the activated carbon was taken out of the constant temperature dryer and allowed to cool to room temperature in a desiccator using silica gel as a desiccant.

[0152] Next, the cooled activated carbon was introduced into the storage funnel of a packed density measurement container (TD-V5, manufactured by Toyo Denji Kikai Seisakusho Co., Ltd.), and using the attached vibrator, it was filled into a 100 mL measuring cylinder up to the 100 mL mark.

[0153] The mass of the activated carbon in the measuring cylinder was measured, and the packing density of the activated carbon was calculated.

[0154] In addition, the ignition residue of the activated carbon obtained in each example and each comparative example was measured according to the method specified in JIS K1474:2014.

[0155] Specifically, the activated carbon obtained in each of the Examples and Comparative Examples was dried at 115±5° C. for 3 hours using a constant temperature dryer (DVS402, manufactured by Yamato Scientific Co., Ltd.).

[0156] Next, the activated carbon was taken out of the constant temperature dryer and allowed to cool to room temperature in a desiccator using silica gel as a desiccant.

[0157] The mass of the cooled activated carbon was measured, and then the activated carbon was ignited in air at 850±50° C. for 1 hour using an electric furnace (Yamato Scientific Co., Ltd., FO811 (model)).

[0158] Next, the obtained ash was allowed to cool to room temperature in a desiccator using silica gel as a desiccant, and its mass (mass of ash) was measured to calculate the ignition residue.

[0159] Next, the packing density of the carbon component was calculated using the formula described in the above embodiment. The results are shown in Table 1.

[0160] (3) Butane adsorption performance The butane adsorption performance of the activated carbon obtained in each of the Examples and Comparative Examples was measured according to the method specified in ASTM D5742.

[0161] Specifically, first, a glass tube specified in ASTM D5742 was dried and its weight (A) was measured.

[0162] Next, the packing density of the activated carbon, which had been dried in advance by the method specified in ASTM D2867, was measured by the method specified in ASTM D2854.

[0163] Next, activated carbon with a mass corresponding to a volume of 16.70±0.05 mL calculated from the measured packing density was weighed and packed into the glass tube, and the total weight (B) was measured.

[0164] Next, the glass tube was immersed in a water bath at 25±0.2° C., and butane was bubbled through the activated carbon in the glass tube at a flow rate of 250±5 mL / min for 900 seconds.

[0165] The glass tube was then removed from the water bath, wiped clean, and the total weight (C) was measured.

[0166] The butane adsorption performance was calculated using the following formula. The results are shown in Table 1.

[0167] Formula: Butane adsorption capacity = [(CB) / (B-A)] x 100 3. Performance evaluation of activated carbon The activated carbon obtained in each of the Examples and Comparative Examples was dried at 115±5° C. for 3 hours using a constant temperature dryer (DVS402, manufactured by Yamato Scientific Co., Ltd.).

[0168] Next, the activated carbon was taken out of the constant temperature dryer and allowed to cool to room temperature in a desiccator using silica gel as a desiccant.

[0169] From the cooled activated carbon, a mass of activated carbon equivalent to a volume of 300 mL calculated from the above-mentioned "packing density of activated carbon" was weighed and packed into a test column.

[0170] The test column had a structure in which an acrylic resin cylinder with an inner diameter of 50 mm was placed between a first lid with an inlet and a second lid with an outlet. Inside the cylinder, from the first lid to the second lid, a buffer material made of nonwoven fabric, activated carbon, another buffer material made of nonwoven fabric, and a dust filter made of nonwoven fabric were layered in this order. The height of the activated carbon layer inside the cylinder (the dimension in the direction in which the cylinder extends) was approximately 150 mm.

[0171] Next, air containing 0.33% by mass of isoflurane at 20±3° C. was allowed to flow into the test column packed with activated carbon from the inlet at a flow rate of 4.5 L / min.

[0172] The cumulative mass of isoflurane that flowed into the test column until the isoflurane concentration in the air flowing out of the outlet exceeded 0.15% by mass was then divided by the mass of the packed activated carbon to determine the isoflurane removal performance.

[0173] [Table 1] [Explanation of symbols]

[0174] 1. Activation System 2 Activation furnace 2A entrance 2B Exit A. Activated carbon C Carbonization raw material 10. Anesthetic gas adsorption filter 11 Container 11A Inlet 11B Outlet 12 Anesthetic gas absorbent G1 Exhaust containing anesthetic gas G2 Exhaust from which anesthetic gases have been removed 100 Inhalation Anesthesia System 101 Ventilator 102 Vaporizer 105 Exhaust line

Claims

1. It has activated carbon, The activated carbon has a "pore volume having a pore radius of 0.6 nm or less" calculated by the MP method of 0.41 mL / g or more, the ratio of the "pore volume having a pore radius of 0.4 nm or less" of the activated carbon calculated by the MP method to the "pore volume having a pore radius of 0.5 nm or less" of the activated carbon calculated by the MP method is 50% or more; An anesthetic gas adsorbent, wherein the packing density of the activated carbon, excluding the ignition residue, is greater than 0.38 g / mL and less than 0.50 g / mL.

2. 2. The anesthetic gas adsorbent according to claim 1, wherein the activated carbon has a "pore volume with a pore radius of 0.6 nm or less" calculated by the MP method of 1.70 mL / g or less.

3. The specific surface area of the activated carbon is 950 m ２ / g or more, 2000m ２ / g or less, 2. The anesthetic gas adsorbent according to claim 1, wherein the butane adsorption capacity of the activated carbon is 24.4% or more and 40.0% or less.

4. The anesthetic gas adsorbent according to claim 1, which is used for adsorbing an anesthetic gas represented by the following general formula (1): General formula (1): 【Chemical 1】 (X is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, or a perfluoromethyl group; n is 0 or an integer of 1 to 3.)

5. The anesthetic gas adsorbent according to claim 4 , wherein the anesthetic gas is isoflurane, desflurane, or sevoflurane.

6. a container having an inlet through which exhaust gas containing an anesthetic gas flows in and an outlet through which the exhaust gas from which the anesthetic gas has been removed flows out; The anesthetic gas adsorbent according to any one of claims 1 to 5, which is disposed in the container between the inlet and the outlet; An anesthetic gas adsorption filter comprising:

7. A ventilator and a vaporizer that vaporizes a volatile anesthetic to generate the anesthetic gas and supplies the generated anesthetic gas to the inhaled air from the artificial respirator; an anesthetic gas adsorption filter according to claim 6, which is connected to the exhaust line of the artificial respirator; An inhalation anesthesia system comprising:

8. A method for removing an anesthetic gas, comprising passing exhaust gas containing an anesthetic gas through the anesthetic gas adsorbent according to any one of claims 1 to 5, thereby removing the anesthetic gas from the exhaust gas.

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