Method and system for removing hydrogen peroxide from gas

Abstract

Methods and apparatus suitable for removing hydrogen peroxide from a gas, such as from a room in the step of sterilizing a hospital room using hydrogen peroxide, or from an exhaust gas stream produced by a sterilization apparatus using hydrogen peroxide as a sterilant, are described.

Description

Technical Field

[0001] This description relates to methods and apparatus suitable for removing hydrogen peroxide from gases. Background Art

[0002] Hydrogen peroxide is known to be useful as a sterilant in both liquid and gaseous forms. Hydrogen peroxide is a powerful oxidizing agent that effectively kills many different bacteria, microorganisms, spores, fungi, and the like on medical devices and items, such as those present in biomass (e.g., cannabis).

[0003] Hydrogen peroxide sterilization, also known as "hydrogen peroxide gas sterilization" or "hydrogen peroxide vapor sterilization," is a low-temperature sterilization method commonly used to sterilize heat-sensitive items. The hydrogen peroxide sterilization method involves contacting the item to be sterilized with hydrogen peroxide vapor within a sterilization environment, allowing sufficient time for the hydrogen peroxide to contact and kill or inactivate bioactive materials on the surface of the item. Hydrogen peroxide sterilization cycles typically require less time than alternative forms of sterilization, such as ethylene oxide sterilization or manual scraping.

[0004] Because hydrogen peroxide is a common household item, users consider it a non-toxic and environmentally safe sterilant. However, when used for industrial-grade sterilization, aqueous concentrations as high as 90% can cause health concerns when evaporated. According to U.S. government regulation 29 CFR 1910.1000, the OSHA 8-hour time-weighted average (TWA) permissible exposure limit (PEL) for hydrogen peroxide in air is 1 part per million (ppm).

[0005] The medical industry uses hydrogen peroxide gas sterilization to sterilize heat-sensitive items at low temperatures. Examples include medical devices, implants, and instruments containing plastics, such as wound dressings, stents, catheters, and encapsulated products. Hydrogen peroxide is also used to sterilize hospital rooms by flooding the interior with gaseous hydrogen peroxide. The amount of hydrogen peroxide in a room must be brought to an acceptable level before it can be occupied.

[0006] Hydrogen peroxide sterilization is also used to sterilize temperature-sensitive items containing valuable chemical molecules (e.g., plants such as cannabis) without degrading the molecules, which have specific metabolic or chemical effects. Equipment designed to perform the method of sterilizing cannabis using hydrogen peroxide vapor is commercially available. Summary of the Invention

[0007] Generally speaking, the following describes methods and systems suitable for reducing the amount of hydrogen peroxide contained in a gas using a carbon adsorbent that has been treated to be particularly effective in eliminating the presence of hydrogen peroxide. The gas can be any gas containing a certain amount of hydrogen peroxide that needs to be removed. According to a specific example, the gas can be the air atmosphere contained in an enclosed space, such as a hospital room that has been sterilized using hydrogen peroxide as a sterilant. In a different example, the gas can be an exhaust gas stream generated by sterilization equipment that uses hydrogen peroxide as a sterilant.

[0008] Hydrogen peroxide is an irritant to the human respiratory system. When hydrogen peroxide vapor is used in a sterilization process, the process generates air containing hydrogen peroxide vapor. Specifically, when hydrogen peroxide is used to sterilize hospital rooms, the room is filled with hydrogen peroxide vapor. Ultimately, the hydrogen peroxide must be removed from the room's air atmosphere, typically by circulating the room's air through a filter placed in the room.

[0009] When hydrogen peroxide is used in a sterilization system that includes a sterilization chamber, the items to be sterilized are placed in the sterilization chamber and exposed to the hydrogen peroxide. After the sterilization step is completed, the sterilization chamber atmosphere, containing concentrated hydrogen peroxide, is then exhausted into the atmosphere of the space containing the sterilization system. When the sterilization system is located in a closed facility, and when multiple sterilization systems are operated in a closed facility, the amount of hydrogen peroxide added to the facility atmosphere from the exhaust gas can accumulate to levels that exceed established health limits.

[0010] The methods and apparatus of the present disclosure can be used to reduce or substantially eliminate the presence of hydrogen peroxide in a gas containing hydrogen peroxide, such as the air atmosphere of a hospital room after sterilization with hydrogen peroxide, or in waste gases generated by a hydrogen peroxide vapor sterilization process. As described, the gas is contacted with a carbon adsorbent that has been treated with a combination of a caustic agent (e.g., a strong base) and a reducing agent. Contacting the gas with the treated carbon adsorbent can remove a substantial amount or substantially all of the hydrogen peroxide contained in the gas.

[0011] A suitable example of a treated carbon adsorbent may contain potassium hydroxide (KOH) as a caustic agent and potassium iodide (KI) as a reducing agent. Both the caustic agent at the surface and the reducing agent at the surface are chemically capable of interacting with hydrogen peroxide vapor in a manner that converts the hydrogen peroxide into different and less toxic compounds, such as oxygen or water. The carbon surface of the adsorbent may also interact with hydrogen peroxide, for example, through a catalytic mechanism, to convert the hydrogen peroxide into less toxic compounds, such as oxygen or water.

[0012] In one aspect, the following description relates to a method of treating a gas to remove hydrogen peroxide from the gas. The method includes providing a gas containing hydrogen peroxide and contacting the gas with a carbon adsorbent including a caustic agent and a reducing agent to reduce the concentration of hydrogen peroxide in the gas.

[0013] In another aspect, the following description relates to a system for treating a gas containing hydrogen peroxide to remove hydrogen peroxide from the gas. The system includes: a housing including an inlet, an outlet, and an interior between the inlet and the outlet; and a carbon adsorbent in the interior between the inlet and the outlet, the carbon adsorbent comprising a porous carbon adsorbent matrix treated with a caustic agent and a reducing agent.

[0014] In another aspect, the present disclosure relates to a method for sterilizing cannabis. The method comprises: placing cannabis in a sterilization chamber containing an atmosphere comprising air; dispensing hydrogen peroxide vapor into the air atmosphere in the sterilization chamber; allowing the hydrogen peroxide to inactivate biologically active materials contained in the cannabis for a period of time; and after the period of time, removing the air from the sterilization chamber as exhaust gas and contacting the exhaust gas with a carbon adsorbent comprising a caustic agent and a reducing agent to reduce the concentration of hydrogen peroxide in the exhaust gas.

[0015] In another aspect, the present disclosure relates to a method for sterilizing a hospital room. The method comprises: dispensing hydrogen peroxide vapor into an air atmosphere within the room; contacting the hydrogen peroxide with surfaces within the room to sterilize the surfaces; and contacting the air atmosphere with a carbon adsorbent comprising a caustic agent and a reducing agent to contact the hydrogen peroxide with surfaces of the carbon adsorbent, thereby reducing the concentration of hydrogen peroxide in the air atmosphere. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1A 、 1B , 1C and 1D illustrate exemplary filter devices as described.

[0017] Figure 2A and 2B An example of a transition plate assembly of an exemplary filter apparatus is shown. Mounting hardware, such as for hanging mounting, may be added but is not shown.

[0018] Figure 3A 、 3B 3C depict the described exemplary filter apparatus including an installed transition plate.

[0019] Figure 4 An exemplary sterilization system having the described filter is shown.

[0020] Figure 5Another exemplary sterilization system having the described filter is shown.

[0021] The drawings are schematic and not necessarily drawn to scale. DETAILED DESCRIPTION

[0022] The present invention describes novel adsorbents, methods, and apparatus that can be used to remove hydrogen peroxide from a gas (e.g., air) by contacting the gas with a carbon adsorbent that has been treated to add a chemical material to the surface of the adsorbent that destroys hydrogen peroxide (e.g., reacts with and converts hydrogen peroxide into less toxic reaction products than hydrogen peroxide, such as water and oxygen). Suitable carbon adsorbents can be treated with a combination of a caustic agent (e.g., a strong base) and a reducing agent. Contacting the gas with the treated carbon adsorbent can remove hydrogen peroxide from the gas and reduce the concentration of hydrogen peroxide in the gas.

[0023] The gas (e.g., air) that is treated to remove hydrogen peroxide can be any gas that contains a certain amount of hydrogen peroxide that needs to be removed from the gas. In a specific example, the gas is the exhaust or "waste" stream generated by sterilization equipment used to perform hydrogen peroxide vapor sterilization, which refers to a process in which hydrogen peroxide vapor is brought into contact with the items to be sterilized (usually within a closed sterilization chamber). In other examples, the air can be the atmosphere contained in an enclosed space, such as a hospital room, containing hydrogen peroxide vapor introduced into the space for the purpose of sterilizing the space.

[0024] Air contains a certain amount of hydrogen peroxide vapor that needs to be removed. The air can contain the typical composition of dry air (about 78% nitrogen, 21% oxygen, and about 0.9% argon and 0.04% carbon dioxide) and optionally water vapor, a number of trace gases and, according to the present specification, a concentration of hydrogen peroxide vapor of, for example, less than 10,000, less than 1,000 or less than 100 parts per million (ppm).

[0025] The amount of hydrogen peroxide in a volume of air can be described as a percentage, or in parts per million or parts per billion. The terms "parts per million" and "parts per billion" are used herein in a manner consistent with the use of these terms in the chemical arts. In this regard, parts per million ("ppm") is often used as a measure of the lower levels (concentrations) of impurities in a gas, expressed as one part of a contaminant per one million parts of air, on a molecular or volume basis. One part per million is equal to 1 x 10 of the total substance. -6 or 0.0001%. One part per billion ("ppb") is equal to 1 x 10 -9 Or 0.0000001%.

[0026] According to the described method, a gas (e.g., air) can be passed through the surface of a carbon adsorbent treated with a caustic agent and a reducing agent to allow the gas and hydrogen peroxide contained in the gas to contact the carbon adsorbent. When the hydrogen peroxide contacts the treated surface of the adsorbent, the hydrogen peroxide is converted into less toxic compounds, such as water and oxygen.

[0027] Carbon adsorbents are concentrated carbon materials derived from carbonaceous polymeric materials or from carbon-based materials of natural origin. Examples include: carbon formed by pyrolysis of synthetic hydrocarbon resins, such as polyacrylonitrile, sulfonated polystyrene-divinylbenzene, polyvinylidene chloride, etc.; cellulosic charcoal; charcoal; and activated carbon formed from natural sources, such as coconut shells, asphalt, wood, petroleum, coal, etc. Activation of carbon (to form "activated carbon") means that the porosity has been altered, such as by steam treatment, to maximize gas absorption.

[0028] Suitable carbon adsorbents can be in any suitable form, such as in the form of granules (also referred to as "particles"). Granules are individual carbon adsorbent fragments, each having a relatively small size, such as less than 2 cm, or less than 1 cm or 0.5 cm, such as particles that pass through a mesh size of 50 to 20, which corresponds to particles of 0.3 to 0.9 mm. The particles can have any range of suitable particle sizes or shapes. Exemplary shapes include beads, granules, pellets, fibers, flakes, shells, saddles, powders, irregularly shaped particles, extrudates of any shape and size, fabric or mesh materials, and composites (of adsorbent and other components), as well as crushed or extruded forms of the aforementioned types of adsorbent materials.

[0029] The carbon adsorbent is treated with a suitable amount of a caustic agent, a base (e.g., a strong base such as potassium hydroxide (KOH)), and a suitable amount of a reducing agent (e.g., potassium iodide (KI)) to place these compounds or their ionic components at the surface of the carbon adsorbent. According to an example, the caustic agent (e.g., KOH) can be applied to the adsorbent in an amount of less than 5% by weight of the caustic agent (e.g., in an amount ranging from 1% to 3% by weight) based on the weight of the adsorbent. The reducing agent (e.g., KI) can also be applied to the adsorbent in an amount of less than 5% by weight of the reducing agent (e.g., in an amount ranging from 1% to 4% by weight) based on the weight of the adsorbent.

[0030] The caustic and reducing agents may be applied to the carbon adsorbent surface by known methods suitable for applying these materials or their derivatives ionic forms to the carbon adsorbent surface. When applied, the caustic or reducing agent, or both, may be present partially or fully in ionic form, meaning that, with reference to the example of potassium hydroxide and potassium iodide, the surface will contain potassium ions (K + ), hydroxide ions (OH - ) and iodide ion (I -Methods of applying chemical materials to the surface of carbon adsorbents are known, examples of which are described in US Pat. No. 9,517,445 and US Pat. Publication No. 2002 / 0152579.

[0031] An apparatus suitable for performing the described method can be in the form of a filtration device comprising: a housing defining a chamber within the housing; an inlet leading from the exterior of the housing to the interior; an outlet leading from the interior of the housing to the exterior; and a carbon adsorbent in the interior that has been treated with a caustic agent and a reducing agent. Gas entering the housing at the inlet passes through the interior, contacts the carbon adsorbent in the interior, and can then exit the housing through the outlet.

[0032] The inlet is adapted to receive a gas stream containing hydrogen peroxide to be removed from the gas by passing the gas through a carbon adsorbent. To remove hydrogen peroxide from the atmosphere of an enclosed space, such as a hospital room, after the room has been sterilized with hydrogen peroxide, the inlet can be an opening adapted to receive air extracted from the enclosed space. The air can be static air from the space and can be directed through the inlet opening using a fan or other flow-directing device located at the inlet as part of the filtration device or alternatively as a separate device. The air is introduced into the filtration device through the inlet, passes through the treated carbon adsorbent, and then exits the filtration device through the outlet with a reduced hydrogen peroxide concentration.

[0033] According to different approaches, the inlet of the filtering device is adapted to receive an exhaust flow from an upstream processing device (e.g., a sterilizing device), which produces an exhaust (e.g., air) containing a certain amount of hydrogen peroxide vapor. The inlet can be adapted to receive a single gas stream from a single upstream processing device, or can be adapted to receive multiple separate gas streams from two or more separate upstream processing devices, each of which produces an exhaust flow containing hydrogen peroxide. The exhaust flow from the processing device can be under sufficient pressure to allow the gas to flow from the processing device and flow through the inlet and filter of the filtering device. Optionally, the gas can be propelled from the upstream processing device to the filtering device under pressure by a fan that is part of the processing device, part of the filtering device, or separate from the processing device and the filtering device.

[0034] The carbon adsorbent can be held and supported within the interior of the filtration device in any suitable manner, such as as part of a sheet containing two porous membranes arranged in a layered manner to support a layer of activated carbon particles between the two sheets. A gas (e.g., air) can flow through the sheet, passing through the two porous membranes, where the gas passes through the carbon adsorbent particles to contact the particle surfaces. The sheet can be bent or folded, for example, to position a high-surface-area sheet within the filtration device between the inlet and outlet.

[0035] Figure 1A 、 1B , 1C and 1D show exemplary filtering equipment. Figure 1A is a top view of the device 100, Figure 1B A top perspective view of the device. Figure 1C is a front view viewed at the inlet 104, and Figure 1D is a side view. As shown, the device 100 includes a housing 102 having a front or front opening 104, which is open as shown and does not have a cover (e.g., a plate) on the front opening. The device also includes a rear or rear opening 106 and an interior containing a pleated filter 110, which contains a treated carbon adsorbent as described herein. A gas flow (see arrows) can enter the interior of the housing through the front opening 104, pass through the filter 110 located in the interior, and exit the interior of the housing by flowing out of the rear opening 106. The gas flowing into the interior has a concentration of hydrogen peroxide that is desired to be reduced. Upon contacting the carbon adsorbent, the hydrogen peroxide is converted into reaction products, such as water and oxygen, and the concentration of hydrogen peroxide in the gas is significantly reduced before the gas passes through the rear opening 106 to exit the housing 102.

[0036] The size and form factor of the housing 102 will be suitable for accommodating a filter having a size and flow capacity capable of handling the movement of any specific volume and rate of gas. The dimensions can be as desired, with the illustrated housing having nominally (approximately) one foot by one foot by one foot exterior dimensions, approximately 300 x 300 x 300 mm. The housing can be adapted to be portable, movable, adapted to be placed on a floor or movable support, or mounted to a ceiling or wall or support at a desired height.

[0037] The exemplary filter apparatus 100 may also include one or more fans as part of the apparatus to generate air flow through the filter. Figure 1E and 1F The exemplary filtering apparatus 100 includes one or more fans 112 located at the front opening 104 , which may be used to generate a flow of air through the front opening 104 , which then passes through the filter 110 and then exits the housing 102 through the rear opening 106 .

[0038] exist Figures 1A to 1D The housing 102 shown in FIG. 1 may be adapted to receive a gas stream from a single gas source, or to receive multiple separate gas streams from multiple different gas sources. Figure 2A and 2BAs shown, a transition plate 130 can be adapted to fit over the front opening 104 to cover and close the opening. The plate can include one or more adapters 140 that correspondingly attach one or more flow conduits (not shown) to the housing 102, such that each flow conduit directs a gas flow to the interior of the housing 102 to contact the filter 110. Each gas flow can come from a processing device, such as a hydrogen peroxide sterilization chamber.

[0039] For more details, see Figure 2A (unassembled view) and 2B (assembled view), the transition plate 130 is sized to cover and enclose Figures 1A to 1D 104 of the housing 102. The plate 130 includes a plurality (four, as shown) of adapters 140 that pass through the openings in the plate 130 and are mechanically attached to the plate 130. As shown, each adapter 140 includes a barbed surface designed to engage the end of a conduit (e.g., a hose or tubing), attaching the conduit to the plate 130 and the housing 102, whereupon gas can flow through the conduit, through the plate 130, and into the housing 120 to pass through the filter 110 and exit the housing 102 through the rear opening 106. Other types of mechanical attachments may be used in place of the barbed surface to attach the adapter 140 to the conduit, such as a fitting, a valve, or a quick connector.

[0040] See Figure 3A 、 3B and 3C, the plate 130 is installed to cover Figures 1A to 1D The plate 130 may be attached to the housing 102 in any manner, such as by screw fasteners at the perimeter of the plate 130, or by any form of latch, fastener, or friction fit engagement that allows the plate 130 to be more quickly disengaged and engaged with the housing 102.

[0041] By using the method and specific use of the filtration system of the present invention, the exhaust gas from the hydrogen peroxide vapor sterilization device can be treated to remove hydrogen peroxide from the exhaust gas. The sterilization device can be used to sterilize any type of items or materials, such as medical items, biomass (e.g., cannabis or other plant materials), or different materials or products. The sterilization device produces an exhaust gas containing a certain concentration of hydrogen peroxide. The exhaust gas passes through the filtration device as described herein, and the concentration of hydrogen peroxide in the exhaust gas is reduced.

[0042] In a more specific application, the exhaust gas is generated by a hydrogen peroxide vapor sterilization device that processes biomass, such as hemp, to sterilize the hemp. Figure 4 Examples of such devices and methods are shown in .

[0043] exist Figure 4In the embodiment shown, hydrogen peroxide vapor sterilization apparatus 200 includes a housing 202, an interior 208, and a front opening 204 that allows access to the interior of a sterilization chamber 206. Apparatus 200 also includes a hydrogen peroxide vapor source 220, a vacuum system 222, a control system 210, and (not shown) various flow control and condition control devices, as well as sensors such as timers, thermostats, and temperature and pressure monitors, which together monitor and control the conditions of the sterilization chamber and the sterilization process.

[0044] As depicted, sterilization chamber 206 contains biomass 230, which may be cannabis or other plant material containing bioactive molecules or agents that require inactivation. To sterilize the biomass and inactivate undesirable bioactive contaminants such as fungi, bacteria, or microorganisms, hydrogen peroxide vapor is generated at source 220 and dispensed into sterilization chamber 206 enclosing biomass 230. The hydrogen peroxide vapor contacts and penetrates the biomass and remains in contact with the biomass for a time effective to sterilize the biomass and inactivate undesirable bioactive contaminants.

[0045] The atmosphere in the sterilization chamber starts as air, and hydrogen peroxide vapor is added to the chamber and the initial air atmosphere.Hydrogen peroxide can be added to the air atmosphere in the sterilization chamber to achieve a hydrogen peroxide concentration suitable for sterilization.

[0046] The sterilization process may be performed at ambient temperature (eg, 15 to 40 degrees Celsius, or 20 to 25 degrees Celsius) and at ambient pressure (eg, 12 to 15 psig (900 to 1200 kPA)).

[0047] After a period of time suitable for the hydrogen peroxide to effectively sterilize the biomass, the gaseous atmosphere from the sterilization chamber is flowed from apparatus 200 to filtration apparatus 100 containing filter 110 comprising a carbon adsorbent treated with a caustic agent and a reducing agent.

[0048] Exhaust gas 240 flows from sterilization apparatus 200 into filtration apparatus 100, passes through filter 110, and then exits filtration apparatus 100 as filtered air 242. Hydrogen peroxide contained in exhaust gas 240 contacts the carbon adsorbent of filter 110 within apparatus 100, and the hydrogen peroxide contained in exhaust gas 240 is converted into compounds, such as water and oxygen. The filtered exhaust gas then exits apparatus 100 as filtered exhaust gas 242, which contains a significantly reduced concentration of hydrogen peroxide compared to the concentration of hydrogen peroxide within exhaust gas 240. For example, the concentration of hydrogen peroxide contained in filtered exhaust gas 242 may be less than 50%, or less than 20%, 10%, or 5% of the concentration of hydrogen peroxide contained in exhaust gas 240.

[0049] Examples of suitable low temperature sterilization systems adapted to sterilize block cannabis and other biomass are commercially available.

[0050] According to the examples of suitable devices described, the sterilization system may include a sterilization device attached to a separate filter device, such as Figure 4 As shown in . As depicted, the sterilization system 200 is a stand-alone unit that can be attached to and detached from the filter system 100 via tubing.

[0051] According to an alternative system, the filter device of the present description may be incorporated into a sterilization device, for example by including the filter in a single housing of the sterilization device. Figure 5 As shown, the sterilization device 200 includes Figure 4 2. Components of an exemplary apparatus of the present invention are shown, wherein a filter 210 is located inside a housing 202. Using this apparatus, exhaust gas 240 passes from a sterilization chamber 206 through a filter 242 and enters a filter chamber 250 containing a filter 110 containing an adsorbent including a caustic agent and a reducing agent. The filter chamber 250 and the filter 110 are located within the housing 202 of the sterilization apparatus 200. The exhaust gas 240 passes through the filter 110 and exits the filter chamber 250 and the apparatus 200 as filtered exhaust gas 242.

[0052] According to various uses of the methods and filtration systems of the present invention, air contained in an enclosed environment such as a room containing hydrogen peroxide vapor (e.g., a hospital room) can be filtered using a filtration device as described herein (e.g., Figure 1E and 1F ) treatment to remove hydrogen peroxide from the air.

[0053] According to an example of such use, a closed room is sterilized by dispensing hydrogen peroxide vapor into the room and allowing the hydrogen peroxide vapor to contact surfaces, including by penetrating porous or fibrous surfaces in the room. The hydrogen peroxide vapor remains in the room for a period of time during which the hydrogen peroxide effectively sterilizes the room.

[0054] After sterilizing a room, unused hydrogen peroxide vapor must be removed from the ambient air in the room. Filtration equipment, e.g. Figure 1D and 1EThe exemplary filtration apparatus 100 can be used to circulate air containing hydrogen peroxide in a room through a filter containing a treated carbon adsorbent as described herein to remove the hydrogen peroxide from the room. The air can be static air ("block" air) that is not effectively circulated through the room. To circulate the air through the filter to remove the hydrogen peroxide from the air, the apparatus 100, including the fan 112, can be placed in the room, for example, on the floor or supported vertically by a table, a stand, or the like. The fan 112 can be powered so that air from the room is drawn into the front opening 104 and then passed through the filter 110, which removes the hydrogen peroxide from the air. The filtered air (filtrate) passes from the filter 110 through the rear opening 106. The filtrate exiting the rear opening 106 has a lower concentration of hydrogen peroxide than the concentration of hydrogen peroxide in the air entering the front opening 104.

Claims

1. A method of treating a gas to remove hydrogen peroxide from the gas, the method comprising: Provide a gas containing hydrogen peroxide, The gas is contacted with a carbon adsorbent comprising a caustic agent and a reducing agent to reduce the concentration of the hydrogen peroxide in the gas.

2. The method of claim 1, wherein the caustic agent comprises potassium hydroxide and the reducing agent comprises potassium iodide.

3. The method of claim 1 or 2, wherein the adsorbent contains up to 5 wt% of the caustic agent based on the weight of the carbon adsorbent.

4. The method according to any one of claims 1 to 3, wherein the sorbent contains up to 5 wt% of a reducing agent based on the weight of the carbon sorbent.

5. The method of any one of claims 1 to 4, comprising reducing the concentration of hydrogen peroxide by at least 50%.

6. The method of claim 5, wherein the concentration of hydrogen peroxide is less than 1 part per million.

7. The method of any one of claims 1 to 6, wherein the gas passed into the carbon adsorbent has a temperature below 40 degrees Celsius.

8. The method of any one of claims 1 to 7, wherein the gas delivered to the carbon adsorbent has a pressure in the range of 12 to 15 psig (900 to 1200 kilopascals (kPA)).

9. The method according to any one of claims 1 to 8, wherein the gas is exhaust gas from a sterilization chamber attached to an inlet.

10. The method of claim 9, wherein the exhaust gas is provided by two or more sterilization chambers attached to the inlet.

11. The method according to claim 9 or 10, wherein the sterilization chamber performs a sterilization method comprising: Place the items to be sterilized in the sterilization chamber, closing the sterilization chamber, Hydrogen peroxide is dispensed into the sterilization chamber.

12. The method of claim 11, wherein the article comprises marijuana.

13. The method of claim 11, wherein the article is a medical device or medical instrument.

14. The method according to any one of claims 1 to 8, wherein the gas is static air inside a hospital room, the method comprising: dispensing hydrogen peroxide vapor into the air atmosphere within the room, contacting the hydrogen peroxide with surfaces within the room to sterilize the surfaces, and The air atmosphere is contacted with the carbon adsorbent so that the air atmosphere contacts the carbon adsorbent and reduces the concentration of hydrogen peroxide in the air atmosphere.

15. A system for treating a gas containing hydrogen peroxide to remove hydrogen peroxide from the gas, the system comprising: a housing comprising an inlet, an outlet, and an interior between the inlet and the outlet, A carbon sorbent is disposed within the interior between the inlet and the outlet and comprises a porous carbon sorbent matrix treated with a caustic agent and a reducing agent.

16. The system of claim 15, wherein the caustic agent comprises potassium hydroxide and the reducing agent comprises potassium iodide.

17. The system of claim 15 or 16, wherein the sorbent contains up to 5 wt% of the caustic agent based on the weight of the carbon sorbent.

18. The system of any one of claims 15 to 17, wherein the sorbent contains up to 5 wt% of a reducing agent based on the weight of the carbon sorbent.

19. The system of any one of claims 15 to 19, comprising a pleated filter membrane containing the carbon adsorbent.

20. The system of any one of claims 15 to 18, comprising a sterilisation device attached to the inlet, the sterilisation device being adapted to produce an exhaust gas containing hydrogen peroxide.

21. The system of any one of claims 15 to 20, comprising two or more sterilization devices attached to the inlet, each sterilization device being adapted to produce an exhaust gas containing hydrogen peroxide.

22. The system of any one of claims 15 to 21, wherein the exhaust gas contains less than 10,000 parts per million of hydrogen peroxide.

23. A method for sterilizing cannabis, the method comprising: The cannabis is placed in a sterilized chamber containing an atmosphere comprising air, distributing hydrogen peroxide vapor into the air atmosphere in the sterilization chamber, allowing hydrogen peroxide to inactivate biologically active materials contained in the cannabis for a certain period of time, After the period of time, the air is removed from the sterilization chamber as exhaust gas and the exhaust gas is contacted with a carbon adsorbent comprising a caustic agent and a reducing agent to reduce the concentration of the hydrogen peroxide in the exhaust gas.

24. The method of claim 23, wherein the caustic agent comprises potassium hydroxide and the reducing agent comprises potassium iodide.

25. The method of claim 23 or 24, wherein the adsorbent contains up to 5 wt% of the caustic agent based on the weight of the carbon adsorbent.

26. The method of any one of claims 23 to 25, wherein the sorbent contains up to 5 wt% of a reducing agent based on the weight of the carbon sorbent.

27. The method of any one of claims 23 to 26, wherein the exhaust gas contains less than 10,000 parts per million hydrogen peroxide.

28. The method of any one of claims 23 to 27, comprising reducing the concentration of hydrogen peroxide by at least 50%.

29. The method of any one of claims 23 to 28, wherein the hemp, the air atmosphere, and the exhaust gas passed to the carbon adsorbent are at a temperature below 40 degrees Celsius.

30. The method of any one of claims 23 to 29, wherein the flue gas passed to the carbon sorbent has a pressure in the range of 12 to 15 psig (900 to 1200 kilopascals (kPA)).

31. A method for sterilizing a hospital room, the method comprising: dispensing hydrogen peroxide vapor into the air atmosphere within the room, contacting the hydrogen peroxide with surfaces within the room to sterilize the surfaces, and The air atmosphere is contacted with a carbon adsorbent including a caustic agent and a reducing agent so that hydrogen peroxide contacts a surface of the carbon adsorbent, thereby reducing the concentration of the hydrogen peroxide in the air atmosphere.

32. The method of claim 31 , wherein the caustic agent comprises potassium hydroxide and the reducing agent comprises potassium iodide.

33. The method of claim 31 or 32, wherein the adsorbent contains up to 5 wt% of the caustic agent based on the weight of the carbon adsorbent.

34. The method of any one of claims 31 to 33, comprising reducing the concentration of hydrogen peroxide by at least 50%.

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