Portable system for production of oxygen

Abstract

To improve a portable system for production of oxygen.SOLUTION: A portable oxygen generating system is provided which comprises a reaction chamber, a feed system for providing and controlling hydrogen peroxide solution to the reaction chamber, and a cooling / condensing system for cooling the hot oxygen and water vapor leaving the reactor and condensing and removing water. The portable chemical oxygen generation system produces humidified, breathable oxygen, which is substantially free of hydrogen peroxide and other contaminants, at a controlled flow and temperature over an extended period of time.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 828,475 (filed April 3, 2019).

[0002] The present disclosure is in the field of oxygen generation, methods of generating oxygen, and chemical oxygen generators. More specifically, the present disclosure provides a portable chemical oxygen generator that delivers high-purity, breathable oxygen. The present disclosure also provides an apparatus / system for low-energy condensation of (water) vapor, for example, to remove water as a by-product of oxygen generation. [Background technology]

[0003] Oxygen is an essential component of medical treatment, which may be chronic or acute. While supplemental oxygen can be lifesaving in emergency situations, the burden of providing oxygen during transport and in remote areas is considerable in cost, transportation, and materials.

[0004] Oxygen cylinders are heavy and present many potential hazards, including the risk of combustion, explosion, and eruptions. Liquid oxygen systems provide larger volumes of gas in a smaller footprint, but are heavy, release gas over a longer period of time, and present a risk of burnout if handled improperly. Additionally, both of these oxygen systems have limited output and must be replenished, presenting logistical challenges in far-forward military operations. Many emergency situations, such as military and mass casualty operations, require simpler, lighter, and longer-lasting oxygen delivery systems.

[0005] Portable oxygen concentrators (POCs) and chemical oxygen generators (COGs) have been proposed as solutions. POCs (sometimes called oxygen concentrators) draw air from the environment (which typically contains approximately 21% oxygen), extract nitrogen, and deliver oxygen at concentrations up to 90–95%. Portable units typically produce up to 6 L / min, while larger (non-portable) devices produce up to 25 L / min. All of these devices operate electrically and require a constant power source. Therefore, a power outage can disrupt the oxygen supply until a backup generator (or battery backup and power inverter) is available. Additionally, portable units deliver gas at low flow rates and pressures, limiting their use in many emergency situations.

[0006] Chemical oxygen generation was first proposed by the work of Joseph Priestly, who discovered oxygen during his work with mercury oxide. Priestly published his findings in 1775. In 1902, The Lancet reported on Kamm's invention of an oxygen generator for medical use. This device used chlorate as an oxygen source and, when heated by an alcohol lamp, produced nearly 4 cubic feet of oxygen before needing to be replenished. Chlorate candles are used as emergency oxygen sources, for example, on submarines. However, the oxygen-generating reaction of chlorate candles is very high temperature (approximately 700–800°C) and therefore potentially very dangerous.

[0007] POCs and COGs have been proposed as an alternative to liquid and pressurized gaseous oxygen systems in far-forward military operations and in disaster and mass-casualty scenarios because of the logistical challenges, weight, and explosion risks associated with liquid and pressurized gaseous oxygen systems. An evaluation of currently available technology indicates that COGs can operate for 30 minutes or less, depending on the manufacturer and design, and their unadjustable output makes them unsuitable for continuous clinical care or long-term operation. Furthermore, COGs may have oxygen flow rates that are too low for many emergency uses.

[0008] Recently, there has been interest in using this technology in areas where supplying oxygen in cylinders or liquid form is logistically difficult or economically prohibitive (e.g., combat casualty care, during disaster situations, and in extreme rural environments in developing countries). Military and mass casualty operations require simpler, lighter, and longer-lasting oxygen delivery systems.

[0009] The FDA mandates that COGs must provide a minimum oxygen flow rate of 6 L / min for a minimum of 15 minutes (21 CFR Part 868.5440). However, the U.S. Army requires a higher output, requiring systems to provide 8 L / min for at least 20 minutes. This is a 75% increase in total O2 output, a level not achievable with available COGs. There has long been a need for a portable, on-demand oxygen generator. Summary of the Invention

[0010] The present disclosure provides a chemical oxygen generation system that produces breathable, humidified oxygen substantially free of hydrogen peroxide and other contaminants at controlled flow rates and temperatures for extended periods of time. In one embodiment, the chemical oxygen generation system is capable of generating a constant flow rate of greater than about 8 L / min up to about 15 L / min of oxygen for periods of greater than about 30 minutes at temperatures below about 40° C.

[0011] In one embodiment, a portable oxygen generation system includes a reaction chamber, a supply system for supplying and controlling a hydrogen peroxide solution to the reaction chamber, and a cooling / condensing system for cooling the hot oxygen and water vapor leaving the reaction chamber and condensing away the water. The reaction chamber includes a catalyst that promotes the chemical decomposition of hydrogen peroxide into oxygen and water, an inlet for introducing the hydrogen peroxide solution into the reaction chamber, and an outlet for releasing the oxygen and water vapor from the reaction chamber. The hydrogen peroxide supply system includes a hydrogen peroxide reservoir containing an aqueous hydrogen peroxide solution and a supply flow regulator for controlling the rate at which the aqueous hydrogen peroxide solution is added to the reaction chamber. The cooling system includes an inlet for receiving oxygen and water vapor, a condenser including two or more drains, each configured to drain water condensed from the water vapor within the cooling system, and an outlet for releasing cooled oxygen gas with reduced water vapor.

[0012] An aspect of the present disclosure is to provide a portable oxygen generating device, the device comprising: a. at least one reservoir for holding a hydrogen peroxide solution; b. one or more reaction chambers containing a catalyst for reacting a hydrogen solution to produce oxygen and water vapor; c. a supply system for supplying hydrogen peroxide from the reservoir to the reactor(s); d. a system in fluid communication with the reactor outlet for cooling and condensing to remove condensed liquid water; e. optionally, a dryer located between the reactor and the cooling system for removing a portion of the water from the oxygen stream; f. optionally, a drive system for moving liquid water to the storage tank; g. optionally, a hydrophobic membrane for removing water at the oxygen outlet of the cooling system; h. optionally, an oxygen flow regulator for regulating the oxygen flow rate at the hydrophobic membrane outlet.

[0013] The cooling system may be an open system operably disposed between the reactor outlet and the hydrophobic membrane (filter), and configured to cool the oxygen gas flowing between the reactor and the filter.

[0014] Another aspect is to provide a device as set forth in any of the preceding claims, wherein the reservoir is configured to hold hydrogen peroxide, a hydrogen peroxide complex, or a hydrogen peroxide solution.

[0015] Another embodiment is a device as described above, wherein the hydrogen peroxide solution is at least 15% hydrogen peroxide or at least 20% hydrogen peroxide. The reservoir may be a cartridge that can be removably connected to a supply system. The cartridge may be configured to be readily replaceable once the hydrogen peroxide solution is depleted.

[0016] Another aspect is to provide a device as described above that allows for quick attachment to a delivery system via a cartridge attachment system, where the cartridge may be collapsible, have a collapsible liner, or be hard-sided or soft-sided.

[0017] Another aspect is to provide a device as described above, wherein the supply unit is configured to generate pressure on the cartridge having a soft surface. The pressure may be generated by a spring, a piston, or air pressure. Additionally or alternatively, the supply system may include a pump, such as a pump selected from a positive displacement pump, a peristaltic pump, a syringe pump, a piston pump, a plunger pump, a screw pump, and a reciprocating pump.

[0018] Another aspect is a device as described above, wherein the reactor is configured to decompose hydrogen peroxide into water and oxygen. The reactor includes a catalyst that promotes the chemical decomposition of hydrogen peroxide into oxygen and water. The catalyst may include one or more active compounds selected from metals, metalloids, metal alloys, metal alloys, metal compounds, and metalloid compounds. The catalyst may further include an electronegative element.

[0019] Another aspect is to provide a device as set forth in any of the preceding claims, wherein the device optionally further comprises a catalytic filter. The catalytic filter, if present, may comprise at least one catalyst, the catalyst comprising one or more active compounds selected from the group consisting of metals, metalloids, alloys of metals, alloys of metalloids, compounds of metals, and compounds of metalloids. The catalytic filter may comprise the same catalyst(s) as the reactor, or may comprise different catalysts.

[0020] Another aspect is to provide a device as described above, wherein the cooling system includes a heat sink. The cooling system may further include at least one fan for facilitating the removal of heat from the cooling system. The fan may be an electric fan.

[0021] Another aspect is to provide a device as set forth in any of the preceding claims, wherein the cooling system includes a condenser. The cooling system including the condenser is configured to facilitate drainage of liquid water condensed by the cooling system. The drainage system may be configured to drain the condensed water from at least one point along the cooling system.

[0022] Another aspect is to provide a device as set forth above, wherein the condensed water is immediately and continuously drained. The cooling system may further include a container for collecting the condensed water.

[0023] Another aspect is to provide a device as described above, wherein the hydrophobic membrane is composed of a material selected from one or more of the group consisting of acrylic copolymer, polytetrafluoroethylene (PTFE), polyvinylidene difluoride (PVDF), polysulfone, and polycarbonate.

[0024] Another aspect is to provide a device as set forth in any of the preceding claims, wherein the oxygen flow regulator is a thermal / mass oxygen (O2) flow meter configured for real-time flow measurement.

[0025] Another aspect is to provide a device as set forth in any of the preceding, wherein the device further comprises an electronic control and display unit, the electronic control and display unit comprising one or more of the following: a. Unit sensor, b. Unit control, c. Unit alarm, d. Unit feedback circuit.

[0026] The control unit may be based on a designated printed circuit board.

[0027] Another aspect is to provide a device as set forth in any of the preceding claims, wherein the unit sensor is configured to measure at least one parameter selected from the group consisting of user-set O2 flow rate, outlet O2 flow rate, outlet O2 temperature, battery capacity, H2O2 storage level, reaction chamber pressure, and / or water tank capacity (e.g., weight).

[0028] Another aspect is to provide a device as set forth in any of the preceding paragraphs, wherein the unit control is configured to control at least one parameter selected from the group consisting of peristaltic pump RPM, cooling fan speed, and water tank drain solenoid, and the control unit may include a feedback circuit for one or more of the parameters disclosed in any of the preceding paragraphs.

[0029] Another aspect is to provide a device as set forth in any of the preceding, wherein the control unit is configured to issue an alert in one or more of the following cases: a. Low H2O2 storage, b. Low battery, c. High water tank level, d. High device pressure, e. oxygen purity; f. Device Maintenance.

[0030] Another aspect is to provide a device as set forth in any of the preceding, wherein the control unit further comprises a data logger, the data logger configured to record a status of the device. The control unit may be configured to communicate with an external system, selected communications being characterized as follows: a. Transferring recorded data to external systems; b. Receiving treatment protocols from external systems.

[0031] Another aspect is to provide a device that is powered by a battery unit, for example the battery may be 12-18V / 4-5Ah rechargeable.

[0032] Another aspect is to provide a device as described above, further comprising a biofeedback sensor. The biofeedback sensor may be configured to detect peripheral blood O2 saturation levels in a patient. The sensor may be configured to communicate with a control unit as disclosed above. For example, the sensor and control unit may be configured to issue an alarm in the event of low or high patient O2 saturation levels.

[0033] An aspect of the present disclosure provides a method for generating oxygen, the method comprising: a. mixing a hydrogen peroxide solution with a catalyst; b. cooling the oxygen and water vapor; c. Discharging liquid water, the water being condensed from the water vapor; d. Optionally, filtering the oxygen and removing water; e. optionally passing the oxygen through a flow regulator.

[0034] Another aspect is to provide a method as set forth in any of the preceding claims, further comprising the step of controlling the flow rate of the hydrogen peroxide solution into the reactor.

[0035] Another aspect is to provide a method as set forth in any of the preceding claims, further comprising passing the oxygen and water vapor through an optional catalytic filter.

[0036] Another aspect is to provide a method as set forth in any of the preceding claims, comprising cooling the oxygen and water vapor using a cooling and / or condensing unit, wherein the cooling is provided at least in part by generating a flow of air (the air being generated by a fan) over at least a portion of the cooling and / or condensing unit.

[0037] Another aspect is to provide a method as set forth in any of the preceding claims, further comprising analyzing the oxygen flow rate and the temperature of the oxygen exiting the cooling system.

[0038] Another aspect is to provide a method as set forth in any of the preceding claims, further comprising alerting a user in the event of one or more of low H2O2 storage, low battery, high system pressure, high water tank level, oxygen purity, and / or low patient O2 saturation level.

[0039] Another aspect is any of the methods set forth above, further comprising: a. Providing oxygen to the patient; or b. providing a method comprising the step of storing oxygen.

[0040] Another aspect is to provide a method as set forth in any of the preceding claims, further comprising detecting an O2 saturation level in the patient.

[0041] Another aspect is to provide a method as set forth in any of the preceding claims, wherein the method further comprises one or more of the following: a. Recording data from your device; b. Recording patient data; c. Transferring data to external systems.

[0042] Another aspect is to provide a method as set forth in any of the preceding paragraphs, further comprising adjusting the oxygen flow rate, the adjustment being controlled by adjusting at least one parameter selected from the group consisting of the flow rate of the hydrogen peroxide solution into the reactor and the flow rate through the flow regulator, the flow rate adjustment being determined by at least one parameter selected from the group consisting of system pressure, reactor pressure, oxygen flow rate, and patient O2 saturation level. Another aspect is to provide a method as set forth in any of the preceding paragraphs, wherein adjusting the oxygen flow rate includes measuring the oxygen flow rate. [Brief explanation of the drawings]

[0043] [Figure 1] 1 is a schematic diagram of a portable chemical oxygen generator according to the present disclosure. [Figure 2] 1 illustrates an embodiment of a portable chemical oxygen generator according to the present disclosure. [Figure 3] 1 illustrates an embodiment of a cooling system according to the present disclosure. [Figure 4] 1 illustrates an embodiment of a heat sink system according to the present disclosure. [Figure 5]Figure 5(A) and Figure 5(B) illustrate an embodiment of a cooling enclosure of a cooling system according to the present disclosure. [Figure 6] 1 illustrates an embodiment of a cooling system according to the present disclosure. [Figure 7] 1 illustrates an embodiment of a portable chemical oxygen generator according to the present disclosure. [Figure 8] FIG. 10 illustrates the effect of gas flow rate on the liquid discharged from each outlet. [Figure 9] FIG. 10 illustrates the effect of gas flow rate on the temperature of the discharged liquid. [Figure 10] FIG. 1 illustrates the effect of gas flow rate on the heat released by a cooling system. [Figure 11] FIG. 10 shows the effect of gas flow rate and catalyst amount on the ejected liquid. [Figure 12] FIG. 10 shows the effect of gas flow rate and catalyst amount on the temperature of the discharged liquid. [Figure 13] FIG. 10 illustrates the effect of gas flow rate and catalyst amount on heat release. DETAILED DESCRIPTION OF THE INVENTION

[0044] A chemical oxygen generator according to the present disclosure is a device that produces oxygen through a chemical reaction. Chemical oxygen generators are important for providing emergency oxygen in situations where other methods, such as oxygen tanks or electrolysis, are not feasible.

[0045] Chemical oxygen generators are used to supplement and increase the concentration of oxygen in a patient's inhaled air. There are many indications for which supplemental oxygen may be needed, including impaired circulation (e.g., due to illness or injury), respiratory problems, decreased lung function, and altitude sickness. Hypoxemia (insufficient oxygen in the blood) is a common complication of acute lower respiratory tract infections (e.g., pneumonia caused by bacteria (e.g., pneumococcus and Haemophilus influenzae) and viruses (e.g., respiratory syncytial virus, influenza virus, coronavirus)) and is a strong risk factor for death.

[0046] Other uses could be anywhere a compact, portable oxygen generator is needed, such as in military operations and in Third World clinics. Chemical oxygen generators may also be used in submarines, aircraft, and by firefighters and mine rescue teams.

[0047] Advantageously, the chemical oxygen generator of the present disclosure is compact and portable, yet reliable and simple to operate. The chemical oxygen generator provides controlled oxygen flow and temperature over extended periods of time. The oxygen flow can be user controlled to deliver oxygen gas from 0 L / min up to about 8 L / min, or up to about 10 L / min, or up to about 15 L / min.

[0048] The device can generate a sustained, controllable flow of breathable oxygen that is substantially free of hydrogen peroxide and other contaminants. The term "substantially free," as used herein, refers to concentrations of hydrogen peroxide or other contaminants that are below medically acceptable levels and therefore present no risk of injury or discomfort to the patient. For example, the chemical oxygen generators disclosed herein provide a patient with an oxygen flow of less than about 1 ppm hydrogen peroxide, or less than about 0.5 ppm hydrogen peroxide. In some embodiments, the device can generate a constant flow of oxygen of up to about 8 L / min, or up to about 10 L / min, or up to about 15 L / min, for more than about 30 minutes at temperatures below about 40°C.

[0049] Importantly, the oxygen flow provided by the chemical oxygen generators disclosed herein is humidified, eliminating the need for external humidification devices. Humidified oxygen improves patient comfort and safety. Increasing oxygen flow rates without adequate humidification can lead to irritation of the nasal mucosa. Oral mucosa may dry out, with associated bleeding and possible airway obstruction. When patients have a nasopharyngeal catheter, endotracheal tube, or tracheostomy, humidifying the oxygen supply is important to keep secretions thin and avoid mucus plugging. Endotracheal tube obstruction caused by inadequate humidification of the oxygen supply has been reported as the cause of many unnecessary hospital deaths. The chemical oxygen generator disclosed herein addresses these concerns by providing a humidified oxygen stream.

[0050] Because the decomposition of hydrogen peroxide is highly exothermic, the oxygen produced in the reaction chamber can reach temperatures above 90°C, up to about 98°C, making it too hot for distribution to a patient. With the chemical oxygen generators described herein, oxygen exits the device, typically via flexible tubing for delivery to the patient, at a comfortable, breathable temperature (i.e., below about 40°C). Advantageously, the oxygen exiting the device is no more than about 10°C above ambient temperature (e.g., room temperature), or no more than about 8°C above ambient temperature, or no more than about 6°C above ambient temperature.

[0051] The portable oxygen generation system includes a reaction chamber, a supply system for supplying and controlling the hydrogen peroxide solution to the reaction chamber, and a cooling / condensing system for cooling the hot oxygen and water vapor leaving the reaction chamber and condensing away the water. The reaction chamber includes a catalyst that promotes the chemical decomposition of hydrogen peroxide into oxygen and water, an inlet for introducing the hydrogen peroxide solution into the reaction chamber, and an outlet for releasing the oxygen and water vapor from the reaction chamber. The hydrogen peroxide supply system includes a hydrogen peroxide reservoir containing an aqueous hydrogen peroxide solution and a supply flow regulator for controlling the rate at which the aqueous hydrogen peroxide solution is added to the reaction chamber. The cooling system includes an inlet for receiving oxygen and water vapor, a condenser including two or more drains, each configured to drain water condensed from the water vapor within the cooling system, and an outlet for releasing cooled oxygen gas with reduced water vapor. oxygen source

[0052] The oxygen source for chemically generating oxygen is hydrogen peroxide or an adduct or complex of hydrogen peroxide. Aqueous solutions of hydrogen peroxide are preferred for use as the oxygen source in the chemical reactions used in the devices described herein.

[0053] The general reaction for the decomposition of hydrogen peroxide used in the reactor to form oxygen gas is as follows: 2H2O2 → O2+ 2H2O

[0054] Hydrogen peroxide is commonly available as an aqueous solution, with concentrations ranging from 3% up to 70%. The concentration of H2O2 is preferably at least 20%, and may be from about 30% to about 70%. catalyst

[0055] The reaction chamber contains a catalyst that promotes the exothermic decomposition of hydrogen peroxide. The catalyst may include a metal, a metalloid, a metal alloy, a metalloid alloy, a metal compound, such as a metal oxide, and a metalloid compound, or a mixture thereof. The catalyst may include a transition metal oxide, such as MnO2, PbO2, Co3O4, VO5, KMnO4, a silver-based catalyst, a Ni-based catalyst, an Fe-based catalyst, a Pt-based catalyst, or a Pd-based catalyst. The metal catalyst may include one or more of silver, gold, zinc, platinum, palladium, or other metal catalysts. Alternatively, an acid may be used to catalyze the reaction.

[0056] When a solid heterogeneous catalyst is used (i.e., a catalyst that is insoluble in water), oxygen production occurs at the surface of the catalyst. The solid heterogeneous catalyst may be selected from the catalysts listed above that are not soluble in water. The advantage of a solid heterogeneous catalyst is that it can be reused multiple times with fresh portions of hydrogen peroxide, maintaining high efficiency.

[0057] The catalyst may be in powder or granular form. Catalysts in powder form may have faster kinetics due to their higher surface area. However, granular forms may be more convenient to handle and reuse. While the high surface area of ​​powdered catalysts helps ensure rapid decomposition of hydrogen peroxide, fine powders may cause problems in retaining the catalyst within the reaction chamber.

[0058] The catalyst may be in the form of granules, e.g., having a diameter of about 0.5 mm to about 5 mm. The catalyst granules may include one or more of a metal, a metalloid, a metal alloy, a metalloid alloy, a metal compound, or a metalloid compound. The granules may further include one or more binder materials.

[0059] The catalyst may be dispersed or coated on the surface of a solid support material or matrix, or alternatively, the catalyst may be impregnated in an inert matrix material or binder.

[0060] The catalyst may include a porous matrix (e.g., a porous scaffold onto which catalytic nanoparticles are deposited). The porous matrix or scaffold may be formed from many suitable materials or combinations of materials. Non-limiting examples of suitable materials include organic or inorganic materials, and may include resins, polymers, metals, glasses, ceramics, activated carbon, textiles, or combinations thereof.

[0061] The porous matrix or scaffold structure may be formed from a polymer sponge. The polymer matrix / support should be selected from materials that can withstand high concentrations of hydrogen peroxide and the high temperatures in the reactor, and may include, for example, polycarbonate, PVC, or high-density polyethylene. The porous scaffold structure may also be formed by synthesis of a poly-high internal phase emulsion (polyHIPE). Polymerization of the continuous phase of the HIPE forms a porous polymer monolith (referred to as polyHIPE). PolyHIPE has high porosity, with pore sizes of approximately 10-100 μm.

[0062] In some embodiments, the porous scaffold may be formed by a particulate porous material. For example, granules of porous material (which represent the support of the porous scaffold) may be bonded together to form the porous scaffold. Various particulate porous materials may be used, including, but not limited to, activated carbon, polymer beads, silica sand, zirconia, alumina, anthracite, etc.

[0063] Several variables can affect the oxygen release rate, including the rate of hydrogen peroxide addition, the temperature of the reaction chamber, and the amount of catalyst in contact with the hydrogen peroxide solution. The catalyst may be eliminated as a variable by ensuring that the reaction chamber contains an excess of catalyst relative to the hydrogen peroxide introduced therein. Once the reaction is running, the temperature of the reaction chamber is maintained at about 90°C or higher, up to about 98°C, while oxygen is produced. With a sufficient amount of solid catalyst (e.g., manganese dioxide) present in the reaction chamber, the rate of oxygen production may be controlled by the rate of addition of aqueous hydrogen peroxide to the reaction chamber. Thus, one aspect is to produce oxygen at a controllable, selectively constant rate. H2O2 reservoir

[0064] The reservoir holds the hydrogen peroxide solution. The reservoir is constructed of an inert, non-reactive material (e.g., stainless steel or polymer / plastic). The reservoir can be a single-use, throwaway or disposable container, or it can be refillable. The reservoir can be a cartridge that holds the hydrogen peroxide solution that is delivered into the reaction chamber by a delivery flow regulator. In some embodiments, the reservoir is part of a system and is refilled from a separate container.

[0065] The reservoir can have a hard or soft surface. In some embodiments, the reservoir may be configured like a "syringe," i.e., consisting of a barrel and a plunger (or piston).

[0066] In some embodiments, the reservoir is a canister capable of holding sufficient aqueous hydrogen peroxide solution to maintain a steady flow of oxygen for at least about 20 minutes, or at least about 30 minutes, at an oxygen flow rate of about 8 L / min, or about 10 L / min, or about 15 L / min. The concentration of hydrogen peroxide is at least about 15%, or at least about 20%. The concentration of hydrogen peroxide may be about 30% to about 70%. The hydrogen peroxide reservoir may hold about 500 ml to about 4000 ml of hydrogen peroxide solution, or about 1000 ml to about 3000 ml of hydrogen peroxide solution. Supply flow regulator

[0067] A user may control the rate at which the hydrogen peroxide solution is delivered to the reaction chamber by the delivery system to maintain a desired oxygen flow. In some embodiments, the delivery flow regulator includes a pump that controls the flow rate of the hydrogen peroxide solution into the reactor. The pump may be any suitable pumping unit known in the art, such as, without limitation, a positive displacement pump, a peristaltic pump, a syringe pump, a piston pump, a plunger pump, a screw pump, or a reciprocating pump. In some embodiments, the reservoir may be collapsible, and the delivery unit is configured to push the hydrogen peroxide solution into the reactor by applying pressure on the reservoir. In some embodiments, the delivery unit acts as a reciprocating pump, with the reservoir forming part of the pump. reactor

[0068] The reaction chamber includes a pressure-resistant housing that causes the chemical decomposition of an oxygen source (typically hydrogen peroxide as an aqueous solution), a catalyst that promotes the chemical decomposition of hydrogen peroxide into oxygen and water, an inlet for introducing the hydrogen peroxide solution into the reaction chamber, and an outlet for releasing oxygen and water vapor from the reaction chamber.

[0069] The reaction chamber may optionally include an overpressure valve, for example to prevent the housing from bursting if the oxygen outlet is blocked. The pressure valve may be configured to adjust the pressure within the reaction chamber by releasing excess gas and / or by adjusting the feed solution flow rate. The flow rate adjustment by the pressure valve may be done directly or by a control unit.

[0070] The reactor outlet may optionally contain a filter or mesh that serves to retain the catalyst within the reaction chamber. Such a filter or mesh may be particularly useful when the catalyst is a powder and has a small particle size.

[0071] The reaction chamber is constructed from an inert, non-reactive material that can withstand temperatures of at least 100°C. The reactor may be constructed from an inert / non-reactive metal or metal alloy (e.g., aluminum, stainless steel, nickel alloys such as Inconel, etc.). Alternatively, the reaction chamber may be constructed from an inert / non-reactive polymeric material. In this context, an inert or non-reactive material is one that does not degrade under the reaction conditions. However, in some embodiments, the material selected for the reaction chamber and that comes into contact with hydrogen peroxide may catalyze the decomposition of hydrogen peroxide.

[0072] Aqueous hydrogen peroxide solution enters the reactor from a supply unit through at least one opening or inlet (e.g., a nozzle or spray nozzle). The solution mixes with a catalyst to rapidly decompose the H2O2 into H2O and O2. The reaction is exothermic, reaching sustained temperatures above 90°C, up to about 98°C. Water therefore evaporates into steam within the reactor. Gas produced by the decomposition of hydrogen peroxide flows out of the reactor through the reactor outlet. Optionally, the reaction chamber may include a drain that can remove any accumulated liquid water. The flow rate of gaseous reaction products (O2, H2O) exiting the reaction chamber is directly proportional to the rate at which the hydrogen peroxide solution is pumped into the reactor. catalytic filter

[0073] Exiting the reaction chamber are the reaction products, oxygen and water vapor, and in some embodiments, some unreacted liquid or gaseous hydrogen peroxide. If some hydrogen peroxide exits the reaction chamber, the oxygen generator may optionally include a secondary reactor (called a catalytic filter) to decompose any remaining hydrogen peroxide.

[0074] The catalytic filter is configured to decompose any hydrogen peroxide that vaporizes or distills from the decomposition reaction and leaves the reaction chamber. The catalytic filter includes one or more catalysts that promote the decomposition of hydrogen peroxide into oxygen and water, as described above. The catalytic filter may include the same catalyst as the reactor or a different catalyst. The gas stream exiting the catalytic filter may be substantially free of hydrogen peroxide, and thus, the hydrogen peroxide in the exiting gas stream is below medically acceptable levels. Cooling Unit / Condenser

[0075] The present disclosure provides a refrigeration unit or system for cooling and separating gas mixtures. Although the refrigeration system is described as being used to cool and separate water from oxygen gas, the refrigeration system may be adapted to cool and separate other mixtures.

[0076] The hot mixture entering the cooling unit includes a mixture of at least two components: a low-boiling component and a high-boiling component. In the case of an oxygen generator, the low-boiling component is oxygen and the high-boiling component is water. The hot vapor flows into a condensing / cooling unit. The condensing / cooling unit includes an enclosure. The enclosure is configured to contain and cool the gas / vapor mixture, thereby converting the condensable vapor to a liquid. In some embodiments, the enclosure is piping or tubing. The condensing enclosure includes at least one drain, preferably multiple drains, running the entire length of the unit to separate condensed liquid from the gas stream and discharge it into a tank. In some embodiments, the cooling enclosure includes multiple drains to discharge condensed liquid throughout the length of the cooling unit, allowing for rapid, continuous discharge to separate the liquid.

[0077] In the oxygen generators described herein, the hot gases exiting the reaction chamber or catalytic filter (if present) are sent into a cooling unit. The gas stream entering the cooling unit is too hot for distribution to the patient, as it may be above about 90°C and up to about 98°C. The cooling unit cools the gas stream to a temperature suitable for comfortable breathing, i.e., below about 40°C.

[0078] The cooling unit is configured to cool the gas stream, condense water vapor into liquid water, and remove the liquid water. The cooling unit can separate the liquid water from the gas stream and discharge it into a storage tank. In some embodiments, the cooling unit can rapidly and continuously discharge liquid water by discharging throughout the length of the cooling unit. The system quickly removes condensed water (which may be hot) as condensation occurs. By removing water from the system throughout the length of the cooling enclosure, the cooling capacity of the cooling system can be directed to efficiently cooling the oxygen gas stream without having to fully cool the condensed water. This arrangement increases cooling efficiency by directing the cooling capacity of the cooling system to cooling the lower volume oxygen stream.

[0079] In one embodiment, the cooling enclosure is formed of a longitudinal section of pipes connected by U-bends. During device operation, the lower U-bend of the cooling system is positioned horizontally, with a drain at the lowest point along the pipe, allowing gravity to assist in continuously draining condensed liquid water from the cooling system. Alternatively, the cooling enclosure may include a pipe containing a gas flow in the form of a horizontal coil, with a drain located along the lowest point for each coil turn. The cooling enclosure may incorporate a heat sink and / or have cooling fins along the exterior of the enclosure. A cooling fluid may be routed through the cooling enclosure to help remove heat from the cooling enclosure. The cooling fluid may be a liquid or gas, and in some embodiments, is a flow of cooling air.

[0080] In a preferred embodiment, the cooling system is an active air cooling system. An electric fan may be used as an active component of the cooling system. The fan passes around the enclosure, creating cooling air to cool the enclosure body. The cooled oxygen exits the condensing enclosure via an exhaust / exit pipe. Advantageously, the oxygen exiting the cooling system is no more than about 10°C above ambient temperature, or no more than about 8°C above ambient temperature, or no more than about 6°C above ambient temperature. Hydrophobic membrane

[0081] In an embodiment, the moist oxygen gas leaving the cooling system passes through a hydrophobic membrane to filter out traces of water. Liquid water can interfere with the accuracy of measuring oxygen flow. The hydrophobic membrane is a microporous membrane of a polymeric material. The hydrophobic membrane may be constructed from any material known in the art for this purpose, such as acrylic copolymers, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polysulfone, and polycarbonate. Commercially available vent plugs with hydrophobic membranes may also be used for this purpose.

[0082] In embodiments, a dryer may be positioned between the reaction chamber or catalytic filter (if present) and the cooling system. The dryer includes a hydrophobic membrane and serves to remove a portion of the water from the gas stream before it enters the cooling system. The dryer may remove up to about 90% of the water from the gas stream, or about 70% to about 90% of the water from the gas stream. Removing a portion of the water from the gas stream before it enters the cooling system may increase the efficiency of the cooling system. The hydrophobic membrane is a microporous membrane of a polymeric material and may be constructed of any material known in the art for this purpose, such as acrylic copolymers, polytetrafluoroethylene (PTFE), or polyvinylidene fluoride (PVDF).

[0083] FIG. 1 shows a schematic of a basic unit 10 of an embodiment of a chemical oxygen generator. A reservoir 11 holds a hydrogen peroxide solution. The reservoir can be disposable after a single use or refillable. In some embodiments, the reservoir is a cartridge that holds the solution delivered to the system. In some embodiments, the reservoir is part of the system and is refilled from a separate container. The reservoir can have a hard or soft surface. The reservoir is constructed from an inert, non-reactive, pharmaceutical-grade material. In some embodiments, the reservoir contracts like a "syringe," i.e., it is constructed from a barrel and a plunger (or piston). In some embodiments, the reservoir is a canister that can hold an aqueous solution of hydrogen peroxide (HO). The hydrogen peroxide percentage is at least 20%, and in some embodiments, 30-70%.

[0084] The supply unit 12 controls the flow rate of the hydrogen peroxide solution into the reactor. In some embodiments, the supply unit is a pump. The pump can be, for example, a positive displacement pump, a peristaltic pump, a syringe pump, a piston pump, a plunger pump, a screw pump, or a reciprocating pump. In some embodiments, the reservoir 12 is collapsible, and the supply unit is configured to push the hydrogen peroxide solution into the reactor by applying pressure on the reservoir. In some embodiments, the supply unit acts as a reciprocating pump, and the reservoir forms part of the pump.

[0085] The supply unit can be configured to control the flow rate according to various parameters, such as the flow rate of the hydrogen peroxide solution, the oxygen flow rate (at the outlet of the device), and the reaction chamber pressure. In some embodiments, the supply unit further includes a pressure sensor.

[0086] The reaction chamber 13 contains a catalyst that promotes the chemical decomposition of hydrogen peroxide into oxygen and water, an inlet for introducing the hydrogen peroxide solution into the reaction chamber, and an outlet for releasing the oxygen and water vapor from the reaction chamber. The reaction chamber is constructed of an inert, non-reactive material that can withstand temperatures of at least 100°C.

[0087] Aqueous hydrogen peroxide solution enters the reactor from a supply unit through at least one opening or inlet (e.g., a nozzle or spray nozzle). The reactor contains a catalyst that catalyzes the decomposition of hydrogen peroxide into water and oxygen. The solution mixes with solid catalyst particles, causing the hydrogen peroxide to decompose into HO and O. The reaction is exothermic, reaching temperatures above 90°C and up to about 98°C. Gases produced by the decomposition of hydrogen peroxide exit the reactor and flow through a catalytic filter 14.

[0088] The reaction chamber can further include a pressure valve. In some embodiments, the pressure valve is configured to adjust the pressure within the reaction chamber by releasing excess gas or by adjusting the solution flow rate. The flow rate can be adjusted directly by the pressure valve or by a control unit.

[0089] The catalytic filter 14 is configured to decompose any vaporized or distilled hydrogen peroxide through a decomposition reaction. The filter can be configured with the same catalyst as present in the reactor or a different catalyst.

[0090] The gas that flows through filter 14 passes into cooling unit 15. The cooling unit is configured to cool the gas and condense water vapor into liquid water. The cooling unit can discharge the liquid into a tank. In some embodiments, the cooling unit discharges the entire length of the cooling unit. In some embodiments, the liquid is discharged immediately and continuously. A water tank can hold and discharge water.

[0091] The gases passing through the cooling unit 15 pass through a hydrophobic membrane (or filter) 16 to remove any water vapor that has not condensed throughout the cooling unit.

[0092] The oxygen flow regulator 17 includes a flow meter that measures the amount of oxygen passing through the filter 16. The flow meter may adjust the supply unit to ensure that the oxygen flow is continuous and at the required level. The flow regulator may also measure the temperature of the gas to ensure that the oxygen is not too hot for the patient. In some embodiments, the flow regulator further includes a valve for adjusting the oxygen flow. The valve can be manual, mechanical, or electromechanical. In some embodiments, control of the valve is by the user, by a control unit, or directly by the flow meter.

[0093] The system includes a control and display unit and a power supply 18. The display unit is capable of displaying all of the important device parameters (oxygen flow, oxygen temperature, water tank content level, storage level, system pressure, battery power level, etc.) The control and display unit is also capable of tracking the overall status of the system (e.g., usage status, catalyst status, maintenance, etc.).

[0094] In some embodiments, the system further includes a biosensor. In some embodiments, the biosensor is an O2 blood saturation sensor connected to the patient. The sensor can be connected to a control unit to track the patient's saturation level. In some embodiments, the control unit is configured to control the oxygen flow rate according to the patient's O2 saturation level. The control unit can control the oxygen rate by adjusting an outlet valve or a supply unit.

[0095] The system includes an outlet port 19 through which the final oxygen produced exits the device and can be delivered to the patient or stored for later use.

[0096] Reference is now made to Figure 2, which illustrates a particular embodiment of an oxygen generating device.

[0097] The oxygen generating device 20 includes a hydrogen peroxide cartridge 21 containing a hydrogen peroxide solution (e.g., 50%-60%). The hydrogen peroxide solution is the substrate for a chemical reaction that produces HO and O. The cartridge volume may be 750-3000 ml, sufficient to generate a 10 L / min O flow rate for 30-45 minutes. The cartridge is designed to be quickly replaced when empty, allowing for a continuous oxygen flow.

[0098] A pump 22 (e.g., a peristaltic pump) moves the hydrogen peroxide solution from the cartridge 21 to a reaction chamber 23 where the chemical reaction occurs. The pump speed (RPM) is controlled through a control unit.

[0099] Hydrogen peroxide is fed into reaction chamber 23 and mixed with the solid catalyst particles, causing the hydrogen peroxide to decompose into water and oxygen. The reaction is exothermic, reaching temperatures above about 90°C, up to 98°C, and producing a maximum constant power of 1,500 W.

[0100] What comes out of the reaction chamber is oxygen, water vapor, some liquid, and gaseous hydrogen peroxide. The flow rate of reaction products (O2, HO) is directly proportional to the pump RPM (the reaction is saturated with catalyst). Pressure gauge 24a tracks the pressure in the reaction chamber. In the event of excessive pressure, pressure valve 24b can release excess gas.

[0101] Once the mixture leaves the reaction chamber, it is sent into catalytic filter 25, which is packed with catalytic particles that chemically break down traces of hydrogen peroxide (liquid or gas) into oxygen and water, preventing even traces of corrosive hydrogen peroxide from reaching the patient.

[0102] Once the hot oxygen and steam exits the catalytic filter 25, it flows into an active air cooling system that includes a fan 26a and a cooling enclosure 26b. As it travels through the system, condensation occurs, with water flowing down through ports at the bottom of each curve in the cooling enclosure. This arrangement efficiently directs cooling power toward condensing small amounts of steam rather than cooling large amounts of water. Fan 26b (60W) is used as the active component of the cooling system.

[0103] Water is collected in a water tank 27 and is drained at appropriate times through a solenoid controlled tap.

[0104] Once the moist oxygen leaves the cooling system, it flows through a hydrophobic membrane 28 to filter out additional water. Any liquid in the O2 pipes can interfere with accurate measurement of O2 flow rate.

[0105] A heat meter 29a and mass oxygen flow meter 29b are used to measure the real-time flow rate of oxygen exiting the device through outlet port 29c.

[0106] Referring now to Figure 3, a cross-section of a cooling system 30 is shown. Cooling air is generated by a fan 31 and passes through a funnel 32 into an area 33 surrounding a pipe 34 containing oxygen and water vapor produced by a reactor. The gas stream is then dehumidified by a hydrophobic membrane 35 before exiting the system through port 36 and being delivered to the patient.

[0107] Reference is now made to Figure 4, which illustrates a heat sink cooling system 40. A mixture of hot oxygen and water vapor enters a sink-through 41. As the gas cools and the water vapor converts to liquid, the liquid water is expelled through a drain 42 at the lowest point of a U-bend 44, reducing the water content of the oxygen exiting the system through 43. Figure 4 shows the cooling unit of Figure 3 rotated 90° on the y-axis (i.e., a side view).

[0108] Reference is now made to Figure 5, which illustrates an exemplary embodiment of a cooling enclosure for a cooling system. Figure 5A shows a cooling enclosure including a series of U-bends. At the lowest point of each lower U-bend 51 is a drain 52 for draining liquid (water) condensed within the cooling enclosure. Figure 5B shows a horizontal coil-shaped cooling enclosure with drain 52 located at the lowest point of each coil turn.

[0109] Referring now to Figure 6, an exemplary embodiment of a cooling system is shown. A hot gas mixture (e.g., hot oxygen and steam) flows into an active air cooling system 60, which includes a fan 66a and a cooling enclosure 66b. As it travels through the system, condensation occurs, with lower boiling point components (e.g., water) condensing and draining downward through drains 66e at the bottom of each lower U-bend 66d in the cooling enclosure. This arrangement efficiently directs cooling power toward a reduced volume of the flow containing the lower boiling point components (e.g., oxygen) rather than toward cooling the larger volume of condensed higher boiling point components (e.g., water). The fan 66b is used as the active component of the cooling system. The higher boiling point components (e.g., water) are collected in a tank 67.

[0110] Reference is now made to FIG. 7, which illustrates a specific embodiment of an oxygen generating device. The oxygen generating device 70 includes a hydrogen peroxide cartridge 71 containing a hydrogen peroxide solution (e.g., 50%-60%). The hydrogen peroxide solution is the substrate for a chemical reaction that produces HO and O. The cartridge volume may be 750-3000 ml, sufficient to generate a flow rate of 10 L / min O or more for 30-45 minutes. The cartridge is designed to be quickly replaced when empty, allowing for a continuous flow of oxygen.

[0111] A pump 72 (e.g., a peristaltic pump) moves the hydrogen peroxide solution from cartridge 71 to reaction chamber 73 where the chemical reaction occurs. The pump speed (RPM) is controlled through control unit 79d.

[0112] Hydrogen peroxide is fed into reaction chamber 73 and mixed with the solid catalyst particles, causing the hydrogen peroxide to decompose into water and oxygen. The reaction is exothermic, reaching temperatures above about 90°C and up to 98°C.

[0113] What comes out of the reaction chamber is oxygen, water (as vapor), some liquid, and gaseous hydrogen peroxide. The flow rate of reaction products (O2, HO) is directly proportional to the pump RPM (the reaction is saturated with catalyst). Pressure gauge 74a tracks the pressure in the reaction chamber. In the event of excessive pressure, pressure valve 74b can release excess gas.

[0114] Once the mixture leaves the reaction chamber, it is sent into catalytic filter 75, which is packed with catalytic particles that chemically break down trace amounts of hydrogen peroxide (liquid or gas) into oxygen and water, preventing even traces of corrosive hydrogen peroxide from reaching the patient.

[0115] Once the hot oxygen and steam exits catalytic filter 75, it flows into dryer 76c, which contains a hydrophobic membrane and serves to remove some of the water from the gas stream before it enters the cooling system.

[0116] The partially dried, hot oxygen and water vapor flows into an active air cooling system that includes fan 76a and cooling enclosure 76b. As it travels through the system, condensation occurs and the liquid water is discharged downward through drains at the bottom of each lower U-bend in the cooling enclosure. The water is collected in water tank 77 and discharged through a solenoid-controlled tap.

[0117] Liquid in the O2 pipes can interfere with accurate measurement of O2 flow. Once the moist oxygen exits the cooling system, it flows through a hydrophobic membrane 78 to filter out additional water. Any water may be expelled from the hydrophobic membrane through an extractor 78a. Optionally, once the oxygen stream exits the hydrophobic filter, it passes through a further dry filter 78b containing a desiccant (e.g., silica).

[0118] A thermometer 79a and mass oxygen flow meter 79 are used to measure the real-time flow rate of oxygen exiting the device through outlet port 79c.

[0119] The device is powered by a battery unit 79e. The battery unit 79e may include a rechargeable 12-18V / 4-5Ah battery. The device further includes an electronic control and display unit 79d. The control and display unit 79d may be configured to control a parameter selected from pump RPM, cooling fan speed, and water tank drainage. The control unit may also include feedback circuitry for one or more of the parameters disclosed anywhere above. The control unit may be configured to monitor and / or alert for one or more of low H2O2 storage, low battery, high water tank level, high device pressure, oxygen purity, and device maintenance. Example Materials and Methods

[0120] The cooling system performance was tested by several parameters: discharged liquid mass and volume, discharged liquid temperature, and heat released from each exit point.

[0121] Data were collected during device operation for 5 minutes using 50% hydrogen peroxide (HO) and a catalyst for hydrogen peroxide decomposition (HydrogenLinkOxyCatalyst). Gas flow was measured by a gas flow meter and indirectly controlled by controlling the hydrogen peroxide flow using a peristaltic pump.

[0122] The volume was measured by a measuring cylinder and the mass was measured by an analytical balance. The temperature was measured by a thermometer (ExTech 4 channel thermometer, model SDL200). The heat was calculated using the following equation:

number

[0123] Table 1 shows the parameters measured in the oxygen generator cooling system. [Table 1]

[0124] 1.1 Effect of gas flow rate

[0125] Theoretically, increasing the gas flow rate requires increasing the flow of hydrogen peroxide, increasing its decomposition reaction rate within the reaction chamber. Adding more reactant (in this case, hydrogen peroxide) helps the catalyst catalyze the decomposition reaction. This results in the production of more oxygen and water, which increases the temperature within the reaction chamber due to heat generation from the exothermic reaction. Therefore, as the flow of hydrogen peroxide increases and the amount of hydrogen peroxide entering the reaction chamber increases, the exiting liquid mass and liquid temperature are expected to increase as more heat is released.

[0126] 1.1.1 Discharged liquid mass

[0127] The products of the hydrogen peroxide decomposition reaction are water and oxygen. In the high flow rate experiments (7 and 10 LPM), trace amounts of hydrogen peroxide were found in the liquid discharged from the first and second outlet points. This indicates that not all of the H2O2 reacted in the reaction chamber, but was condensed in the cooling system. It can be concluded that the amount of catalyst should be increased to compensate for the high flow rate of H2O2.

[0128] Figure 8 shows the liquid mass discharged from outlet points 1 to 4 at flow rates of 5, 7, and 10 LPM. As can be seen, only at the high flow rate of 10 LPM, the fourth outlet point was involved in the cooling process. In addition, the trend is the same for all three flow rates. As the number of outlet points increases, the discharged liquid mass decreases. This can be explained by the fact that most of the liquid is condensed at the first outlet point due to the high temperature difference (the temperature of the gas stream when it leaves the reaction chamber is 92-96°C).

[0129] The 10 LPM graph is significantly higher than the other two, but the difference between 5 and 7 LPM is small. However, in the 7 LPM case, the total mass of liquid expelled from the cooling system is higher (although not significantly). Also, in the 7 LPM case, a third exit point was involved in the cooling process, whereas in the 5 LPM case, only two exit points were required.

[0130] 1.1.2 Discharged liquid temperature

[0131] The temperature of the exiting liquid indicates the efficiency of the cooling process at each outlet point. As shown in Figure 9, for all three flow rates, the temperature decreases as the number of outlet points increases. Comparing between different flow rates, it can be seen that the temperature decreases with flow rate at each outlet point. The highest efficiency was achieved at 5 LPM and the lowest at 10 LPM. The highest flow rate produced the most products (water and oxygen). Therefore, the cooling required is "harder." This is reflected by the higher temperature of the exiting liquid and the number of outlet points required for cooling.

[0132] 1.1.3 Heat release

[0133] The heat released during the cooling process was calculated based on the liquid mass discharged and the temperature difference between the inlet and outlet. This parameter represented the cooling efficiency as a temperature. Figure 10 shows the heat released from each outlet point at different flow rates. The heat released at each outlet point decreases with increasing point number because less mass needs to be cooled, resulting in a smaller temperature delta and therefore less heat to release. This trend is present at all flow rates tested. The lowest flow rate, 5 LPM, required the lowest hydrogen peroxide flow rate. A low reactant flow rate allowed the catalyst to fully catalyze the hydrogen peroxide, allowing the cooling system to reject more heat at the beginning of the cooling system than in the other gas flow experiments. A high hydrogen peroxide flow rate (such as in the 7 and 10 LPM experiments) reduces the cooling efficiency due to the increased amount of hot gas that must be cooled. This is reflected by the higher liquid temperature, as shown in Figure 9, and the lower heat released, as shown in Figure 10.

[0134] 1.2 Effect of catalyst amount

[0135] In general, chemical reactions occur faster in the presence of a catalyst because the catalyst provides an alternative reaction pathway with a lower activation energy than would be possible with an uncatalyzed mechanism. Therefore, the amount of catalyst has a significant effect on the reaction rate. Higher amounts of catalyst are expected to result in higher reaction rates, until a significant excess of catalyst is present.

[0136] 1.2.1 Discharged liquid mass

[0137] Figure 11 shows the effect of catalyst loading on the discharged liquid for different flow rates. For the same liquid flow rate (constant pump voltage), a longer time was required in the low catalyst experiments (30 seconds for all low catalyst experiments) to achieve a specific gas flow rate. Because the total experiment time was constant (5 minutes), the amount of discharged liquid obtained from the first outlet point decreased during that time. For the second and third outlets, the trend was opposite because there was less liquid left to condense (most of the liquid was condensed at the first outlet point). However, at the high flow rate of 10 LPM, a lower catalyst loading resulted in a larger amount of liquid being discharged from all outlet points compared to the higher loading. This can be explained by the "overload phenomenon" observed in the high flow rate experiments. As explained in Section 1.1.1, 10 LPM was found to be too high a flow rate for the reactor design. As a result, hydrogen peroxide entered the reactor chamber in an overload, but the catalyst was unable to catalyze it at the same rate. The "overload phenomenon" results in an incomplete reaction, resulting in the presence of hydrogen peroxide in the discharged liquid. This phenomenon is stronger in the high flow rate (10 LPM) and low catalyst experiments, which means that more hydrogen peroxide is discharged compared to the high catalyst experiments. Because hydrogen peroxide is denser than water, the discharged liquid mass is higher in the low catalyst case.

[0138] 1.2.2 Discharged liquid temperature

[0139] The temperature results are shown in Figure 12. The results show a dominant behavior. For a given flow rate, the lower the catalyst loading, the higher the resulting temperature. This is expected since the mass of discharged liquid is lower. This means less energy is released through the condensation process, resulting in a higher temperature. However, the 10 LPM does not show consistent behavior. For the first outlet point, the lower catalyst has almost the same liquid discharge temperature, but for the second outlet, the lower catalyst has a higher liquid discharge temperature, and for the third outlet, the higher catalyst has a higher temperature. Again, it is reasonable to assume that the overload prevents some reaction of hydrogen peroxide in the reaction chamber, and that some of the reaction is occurring in the cooling system, so no conclusions can be drawn based on the temperature results.

[0140] Comparing different flow rates, it can be seen that as the flow rate decreases, for each catalyst amount, the temperature at each outlet point decreases because more liquid is condensed and therefore more of the released heat is consumed in the endothermic condensation process.

[0141] 1.2.3 Heat Dissipation

[0142] The heat release results shown in Figure 13 reveal the following: As the flow rate increases, the heat released from each outlet decreases for each catalyst load (except for the 10 LPM case, which was overloaded as explained). The high heat released by the cooling system represents the efficiency of the cooling process. The lowest flow rate for each catalyst load gave the highest efficiency because it had the largest delta between the inlet and outlet temperatures. Based on Equation 1, the heat calculations are based on this temperature difference. The trend is the same for all experiments: the heat released from each outlet point decreases dramatically between the first and second outlet points, and the gradient becomes more gradual between the second and third outlets. This shows that the first outlet point releases most of the heat, making it the most efficient cooling point. A comparison between the two catalyst amounts for the same flow rate (except 10 LPM) reveals that the higher the catalyst amount, the higher the heat release. This is due to the fact that the higher the amount, the better the catalysis that is exerted on the reaction, and therefore the higher the amount of product obtained during the experiment (while the pump voltage is constant) and the more heat is produced in this exothermic reaction.

[0143] The results show that as the exit point number increases, the mass of liquid discharged decreases. For each flow rate, the temperature of the exiting liquid decreases as the exit point number increases. At each exit point, the temperature also decreases with flow rate. The heat released at each exit point decreases with increasing point number. At the highest flow rates, the largest amounts of products (water and oxygen) were produced.

[0144] The highest efficiency was achieved at 5 LPM and the lowest efficiency at 10 LPM. The lowest efficiency was achieved at each catalyst volume with the lowest flow rate. The first outlet point was the most efficient cooling point.

Claims

1. 1. A portable oxygen generation system comprising: A reaction chamber comprising: a catalyst that promotes the chemical decomposition of hydrogen peroxide into oxygen and water; an inlet for introducing a hydrogen peroxide solution into the reaction chamber; a reaction chamber including an outlet for releasing oxygen and water vapor from the reaction chamber; a hydrogen peroxide delivery system in fluid communication with the inlet of the reaction chamber, a hydrogen peroxide reservoir containing an aqueous hydrogen peroxide solution; a supply flow regulator that controls the rate at which the aqueous hydrogen peroxide solution is added to the reaction chamber; 1. A cooling system comprising: an inlet in fluid communication with the outlet of the reaction chamber for receiving oxygen and water vapor; a condenser including two or more drains, each configured to drain water condensed from the water vapor within the cooling system; and and an outlet for releasing cooled oxygen gas with reduced water vapor.

2. 10. The device of claim 1, wherein oxygen flow from the device is directly proportional to the rate at which the aqueous hydrogen peroxide solution is introduced into the reaction chamber during device operation.

3. 3. The device of claim 1 or 2, wherein the catalyst is selected from metals, metalloids, alloys of metals, alloys of metalloids, compounds of metals, such as metal oxides, and compounds of metalloids, or mixtures thereof.

4. The device of any one of claims 1 to 3, wherein the catalyst comprises manganese dioxide.

5. The device of any one of claims 1 to 4, wherein the aqueous hydrogen peroxide solution is at least about 15% or at least about 20% hydrogen peroxide.

6. The device of any one of claims 1 to 5, wherein the aqueous hydrogen peroxide solution is about 30% to about 70% hydrogen peroxide.

7. The device of any one of claims 1 to 6, wherein the hydrogen peroxide reservoir is a replaceable cartridge.

8. The device of any one of claims 1 to 7, wherein the supply flow regulator comprises a user-controlled pump.

9. 9. The device of claim 8, wherein the pump is selected from the group consisting of a positive displacement pump, a peristaltic pump, a syringe pump, a piston pump, a plunger pump, a screw pump, and a reciprocating pump.

10. 10. The device of any one of claims 1 to 9, further comprising a catalytic filter located in fluid communication between the outlet of the reaction chamber and the inlet of the cooling system, the catalytic filter including the catalyst for decomposing hydrogen peroxide into oxygen and water.

11. A device according to any preceding claim, wherein the condenser is configured to expel liquid water throughout the length of the condenser.

12. 12. The device of claim 11, wherein the liquid water is instantly and continuously discharged from the condenser.

13. The device of any one of claims 1 to 12, wherein the cooling system further comprises a container for collecting condensed water.

14. The device of any one of claims 1 to 13, wherein the cooling system includes a heat sink.

15. The device of any preceding claim, wherein the cooling system includes one or more fans.

16. The device according to any one of claims 1 to 15, wherein the device further comprises a hydrophobic membrane for removing residual water at the outlet of the cooling system.

17. 17. The device of claim 16, wherein the hydrophobic membrane comprises a material selected from the group consisting of acrylic copolymers, polytetrafluoroethylene (PTFE), and polyvinylidene fluoride (PVDF).

18. 18. The device of any one of claims 1 to 17, wherein the oxygen stream exiting the device contains less than about 1 ppm hydrogen peroxide, or less than about 0.5 ppm hydrogen peroxide.

19. 19. The device of any one of claims 1 to 18, wherein the device generates a constant flow of oxygen of up to about 8 L / min, or up to about 10 L / min, or up to about 15 L / min, at a temperature of less than about 40°C, for a period of more than about 30 minutes.

20. 20. The device of any one of claims 1 to 19, wherein the oxygen exiting the device is no more than about 10°C above ambient temperature, or no more than about 8°C above ambient temperature, or no more than about 6°C above ambient temperature.

21. 1. A device for cooling and separating a gas mixture, comprising: an inlet for receiving a gas mixture, the mixture including at least a higher boiling component and a lower boiling component; a condenser including two or more drains, each configured to continuously drain condensed liquid including the higher boiling point components from the refrigeration system by gravity; at least one source of cooling fluid; an outlet for discharging the cooled gas mixture having reduced high boiling point components.

22. 22. The device of claim 21, wherein the condenser is formed of longitudinal sections of pipe connected by U-bends, each lower U-bend of the condenser including a drain outlet at the lowest point along the U-bend, such that gravity assists in continuously draining the condensed liquid from the condenser through the drain outlets.

23. 22. The device of claim 21, wherein the condenser is in the form of a coil and has a drain located at each lowest point for each coil turn.

24. A device according to any one of claims 21 to 23, wherein the condenser comprises three or more drain outlets.

25. A device according to any one of claims 21 to 24, wherein the condenser is incorporated within the heat sink.

26. A device according to any one of claims 21 to 25, wherein the cooling fluid is air and the source of cooling air is an electric fan.

27. The device according to any one of claims 21 to 26, wherein the high boiling point component is water and the low boiling point component is oxygen.

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