JP2018104791A - Gas producing apparatus and gas producing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas producing apparatus that is advantageous to enhance gas production efficiency.SOLUTION: A gas producing apparatus of the present disclosure (1a) comprises a housing (10), a partition wall (20), a first electrode (31), a second electrode (32), a first gas-liquid separation film (41), a first communication path (50), and a second communication path (51). The partition wall (20) partitions an inner space of the housing (10) into a first chamber (11) and a second chamber (12). The first electrode (31) is arranged in the first chamber (11). The second electrode (32) is arranged in the second chamber (12), and is electrically connected with the first electrode (31). The first gas-liquid separation film (41) is arranged in the first chamber (11). The first communication path (50) possesses a first exhaust port (52) brought into contact with an upper portion of the first chamber (11) above the first gas-liquid separation film (41). The first gas-liquid separation film (41) has a larger area than a cross-sectional area of the first exhaust port (52).SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a gas generation device and a gas generation method.

  Conventionally, an apparatus for generating hydrogen gas by electrolyzing an aqueous liquid is known. For example, Patent Document 1 describes a gas generation device 200 as shown in FIG. The gas generator 200 generates hydrogen gas and oxygen gas by electrolyzing the aqueous liquid 225.

  The gas generation apparatus 200 includes a tank 210, a first electrode 221, a second electrode 222, a separator 223, a DC power source 224, a gas-liquid separation film 291, a gas-liquid separation film 292, a connection member 254a, and a connection member 254b. ing. The tank 210 is divided into a first tank 211 and a second tank 212 by a partition wall 210 a and a separator 223. An aqueous liquid 225 is disposed in the tank 210. The first electrode 221 is disposed in the first tank 211. The second electrode 222 is disposed in the second tank 212. A cylindrical portion 211a exists above the first tank 211, and a gas-liquid separation membrane 291 is disposed in the cylindrical portion 211a. A cylindrical portion 212a exists above the second tank 212, and a gas-liquid separation membrane 292 is disposed in the cylindrical portion 212a. When a voltage is applied between the first electrode 221 and the second electrode 222 so that the first electrode 221 becomes an anode, oxygen gas 226 is generated on the surface of the first electrode 221, and the second electrode Hydrogen gas 227 is generated on the surface of 222.

  In the second tank 212, the volume V2 of the aqueous liquid 225a exists above the position where the separator 223 and the aqueous liquid 225 are in contact with each other. In addition, a space of volume V1 exists between the aqueous liquid 225 and the gas-liquid separation membrane 291 in the first tank 211. The gas generator 200 is used in a state where the volume V2 is larger than the volume V1. In the gas generator 200, even if the liquid level of the aqueous liquid 225 in the first tank 211 reaches the gas-liquid separation film 291, the liquid level of the aqueous liquid 225 in the second tank 212 does not reach the separator 223. . Therefore, according to the gas generation device 200, even if the pressure of the second gas 227 (hydrogen gas) in the second tank 212 increases, the first gas 226 (oxygen gas) and the second gas 227 ( Hydrogen gas) is not mixed.

JP 2014-95115 A

  The gas generating device described in Patent Document 1 has room for improvement from the viewpoint of increasing gas generation efficiency. Therefore, the present disclosure provides a novel gas generation device that is advantageous for increasing the gas generation efficiency.

This disclosure
A gas generating device that generates gas from an aqueous solution by an electrochemical reaction,
A housing capable of containing the aqueous solution;
A partition partitioning the internal space of the housing into a first chamber and a second chamber;
A first electrode disposed in the first chamber;
A second electrode disposed in the second chamber and electrically connected to the first electrode;
A first gas-liquid separation membrane disposed in the first chamber;
A first series passage that communicates the first chamber with an external space of the housing, and has a first discharge port that is in contact with the upper portion of the first chamber above the first gas-liquid separation membrane. A first series of passages;
A second communication path for communicating the second chamber and the outer space of the housing, the second communication path having a second discharge port in contact with the upper portion of the second chamber,
The first gas-liquid separation membrane has an area larger than the cross-sectional area of the first discharge port.
A gas generator is provided.

  The above gas generator is advantageous in increasing the gas generation efficiency.

FIG. 1 is a cross-sectional view illustrating an example of a gas generation device of the present disclosure. FIG. 2A is a diagram showing the action of the first gas-liquid separation membrane on bubbles. FIG. 2B is a diagram illustrating the action of the first gas-liquid separation membrane on bubbles. FIG. 3 is a cross-sectional view illustrating another example of the gas generation device of the present disclosure. FIG. 4 is a diagram illustrating an example of the arrangement of the gas generation device in FIG. 3. FIG. 5 is a cross-sectional view illustrating still another example of the gas generation device of the present disclosure. 6 is a cross-sectional view of the gas generating device taken along line VI-VI in FIG. FIG. 7 is a cross-sectional view of the gas generating device taken along line VII-VII in FIG. FIG. 8 is a diagram schematically showing a conventional gas generator.

<Knowledge based on study by the present inventor>
In the gas generator 200, gas generated by electrolysis of the aqueous liquid 225 forms bubbles. This bubble rises in the aqueous liquid 225 and, in some cases, accumulates in the upper portion of the first tank 211. In this case, the bubbles must pass through a narrow channel inside the cylindrical portion 212a. If bubbles are generated one after another and accumulated in the upper part of the first tank 211, a part of the bubbles may cover the first electrode 221. When the bubbles cover the first electrode 221, the aqueous liquid 225 is not sufficiently supplied to the first electrode 221. Thereby, the area (reaction area) of the portion where the electrolysis reaction of the aqueous liquid 225 is performed in the first electrode 221 is reduced, and the efficiency of the electrolysis reaction of the aqueous liquid 225 may be reduced. As a result, the gas generation efficiency decreases. In addition, when an electrode including a photocatalyst is irradiated with light to generate an electrochemical reaction to generate a gas from an aqueous solution, a part of the side wall that defines the space in which the electrode is disposed is formed of a light-transmitting material. It is possible. In this case, if bubbles accumulate in the upper part of the space in which the electrode is arranged, the bubbles cover the surface of the electrode or the translucent side wall, the efficiency of the electrochemical reaction due to light irradiation to the electrode is reduced, and gas is generated. Efficiency can be reduced.

  Therefore, the present inventor has improved the efficiency of gas generation if it can prevent bubbles generated in the aqueous solution from accumulating in the space where the electrode for the electrochemical reaction is accumulated when generating gas from the aqueous solution by electrochemical reaction. I thought it could be significantly improved. In view of this, the present inventors have devised a technique that can prevent air bubbles from accumulating in a space where an electrode for an electrochemical reaction is arranged, and devised a gas generation device of the present disclosure. In addition, said knowledge is knowledge based on examination of this inventor, and does not admit as prior art.

The first aspect of the present disclosure is:
A gas generating device that generates gas from an aqueous solution by an electrochemical reaction,
A housing capable of containing the aqueous solution;
A partition partitioning the internal space of the housing into a first chamber and a second chamber;
A first electrode disposed in the first chamber;
A second electrode disposed in the second chamber and electrically connected to the first electrode;
A first gas-liquid separation membrane disposed in the first chamber;
A first series passage that communicates the first chamber with an external space of the housing, and has a first discharge port that is in contact with the upper portion of the first chamber above the first gas-liquid separation membrane. A first series of passages;
A second communication path for communicating the second chamber and the outer space of the housing, the second communication path having a second discharge port in contact with the upper portion of the second chamber,
The first gas-liquid separation membrane has an area larger than the cross-sectional area of the first discharge port.
A gas generator is provided.

  According to the first aspect, the first gas-liquid separation membrane is disposed in the first chamber below the first discharge port. Bubbles generated in the aqueous solution in the first chamber by the electrochemical reaction disappear in contact with the first gas-liquid separation membrane before reaching the first discharge port. Moreover, since the first gas-liquid separation membrane has an area larger than the cross-sectional area of the first discharge port, even if bubbles are generated one after another, a large number of bubbles come into contact with the first gas-liquid separation membrane for a predetermined period and disappear. To do. For this reason, bubbles generated in an aqueous solution by an electrochemical reaction are unlikely to accumulate in the upper portion of the first chamber. As a result, the first electrode is not easily covered with bubbles, and the efficiency of the electrochemical reaction (gas generation efficiency) in the gas generation device tends to be high. Thus, the gas generating device according to the first aspect is advantageous in increasing the gas generation efficiency.

  In the second aspect of the present disclosure, in addition to the first aspect, the first gas-liquid separation membrane is in contact with the liquid surface of the aqueous solution accommodated in the housing during the operation of the gas generation apparatus. I will provide a. According to the second aspect, the bubbles generated in the aqueous solution are likely to disappear in contact with the first gas-liquid separation membrane immediately after reaching the liquid level of the aqueous solution. For this reason, bubbles are unlikely to accumulate in the upper part of the first chamber, and the efficiency of the electrochemical reaction in the gas generating device tends to be high.

  According to a third aspect of the present disclosure, in addition to the first aspect or the second aspect, the second gas-liquid separation membrane is disposed below the second discharge port in the second chamber. Provided is a gas generation device further comprising a second gas-liquid separation membrane having an area larger than the cross-sectional area of the outlet. According to the third aspect, bubbles generated in the aqueous solution in the second chamber by the electrochemical reaction disappear in contact with the second gas-liquid separation membrane. Further, even if bubbles are generated one after another, a large number of bubbles disappear in contact with the second gas-liquid separation membrane in a predetermined period. For this reason, bubbles generated in an aqueous solution by an electrochemical reaction are unlikely to accumulate in the upper portion of the second chamber. As a result, the second electrode is not easily covered with bubbles, and the efficiency of the electrochemical reaction (gas generation efficiency) in the gas generation device tends to be high.

  According to a fourth aspect of the present disclosure, in addition to the third aspect, a gas generating device is provided in which an area of the first gas-liquid separation membrane is smaller than an area of the second gas-liquid separation membrane. For example, when the volume of gas generated in the first chamber by an electrochemical reaction is smaller than the volume of gas generated in the second chamber, bubbles generated in the aqueous solution in the first chamber Often, there are fewer bubbles than According to the fourth aspect, when fewer bubbles are generated in the first chamber than bubbles generated in the second chamber, this can be used to make the first gas-liquid separation membrane smaller.

  According to a fifth aspect of the present disclosure, in addition to any one of the first to fourth aspects, the casing has a first inner surface facing the first electrode and facing obliquely downward. And a gas generating device in which an angle β formed by a plane including the lower surface of the first gas-liquid separation membrane and a plane including the first inner surface is greater than 90 ° and less than 180 °. To do. According to the fifth aspect of the present disclosure, the space in which bubbles generated in the aqueous solution in the first chamber accumulate is likely to be small. For this reason, bubbles generated in an aqueous solution by an electrochemical reaction are unlikely to accumulate in the upper portion of the first chamber. As a result, the gas generation efficiency in the gas generator tends to increase.

  According to a sixth aspect of the present disclosure, in addition to the fifth aspect, the housing includes an upper outer surface that is inclined downward with respect to a plane including the first inner surface, and a plane including the upper outer surface and the first inner surface. A gas generation device is provided in which the angle γ formed by is greater than 90 °. According to the sixth aspect, it is easy to adjust the angle β formed by the plane including the lower surface of the first gas-liquid separation membrane and the plane including the first inner surface to an angle larger than 90 °.

  In a seventh aspect of the present disclosure, in addition to the sixth aspect, an angle β formed by a plane including the lower surface of the first gas-liquid separation membrane and a plane including the first inner surface defines the upper outer surface and the first inner surface. Provided is a gas generating device having an angle γ or less formed with a plane to be included. According to the 7th aspect, the space where the bubble which generate | occur | produced in the aqueous solution of a 1st chamber accumulates tends to become small. For this reason, bubbles generated in an aqueous solution by an electrochemical reaction are unlikely to accumulate in the upper portion of the first chamber. As a result, the gas generation efficiency in the gas generator tends to increase.

  The eighth aspect of the present disclosure provides the gas generating device, in addition to the fifth aspect, the first gas-liquid separation membrane extends horizontally. According to the sixth aspect, the space in which bubbles generated in the aqueous solution in the first chamber accumulate tends to be small. In addition, the entire first gas-liquid separation membrane tends to come into contact with the liquid surface of the aqueous solution in the first chamber. Thereby, it is difficult for bubbles to accumulate in the upper part of the first chamber, and the gas generation efficiency in the gas generation device tends to be high.

  According to a ninth aspect of the present disclosure, in addition to any one of the fifth aspect to the eighth aspect, the casing includes a side wall that defines the first inner surface and has translucency, and the first electrode includes: A gas generation device including a photocatalyst is provided. According to the ninth aspect, gas can be generated from the aqueous solution by an electrochemical reaction by irradiating the first electrode with light from the light source through the side wall. In addition, when the light source is positioned obliquely above the gas generating device, the amount of light applied to the first electrode tends to increase. Thereby, the efficiency of an electrochemical reaction and by extension, the generation efficiency of gas can be improved.

  In a tenth aspect of the present disclosure, in addition to any one of the sixth to ninth aspects, the housing is inclined downward with respect to a plane including the first inner surface and is upward with respect to a horizontal plane. A part of the lower outer surface of the gas generating device located above the two adjacent gas generating devices when the plurality of gas generating devices are arranged one above the other. Provided is a gas generating device capable of overlapping along a vertical direction with a part of the upper outer surface of the gas generating device located below of the two gas generating devices. According to the tenth aspect, when the plurality of gas generation devices are arranged one above the other, the installation area of the plurality of gas generation devices can be reduced.

  According to an eleventh aspect of the present disclosure, in addition to the tenth aspect, an angle formed by the upper outer surface and a horizontal plane is smaller than an angle formed by the lower outer surface and a horizontal plane. According to the eleventh aspect, when a plurality of gas generating devices are arranged one above the other, a space can be created between the gas generating devices adjacent to each other in the vertical direction. For example, this space can be used to take out the gas generated by the gas generator.

  In a twelfth aspect of the present disclosure, in addition to any one of the first aspect to the eleventh aspect, an inner surface of the housing is disposed in the first chamber located below the first gas-liquid separation membrane. There is provided a gas generating device including a first guide surface extending obliquely upward from a specific position toward the first gas-liquid separation membrane. According to the twelfth aspect, bubbles generated in the aqueous solution in the first chamber rise toward the first gas-liquid separation membrane along the first guide surface. Thus, the bubbles are guided to the first gas-liquid separation membrane by the first guide surface. Thereby, it is difficult for bubbles to stay in a specific portion of the first chamber, and the gas generation efficiency in the gas generation device tends to be high.

  A thirteenth aspect of the present disclosure provides the gas generation device, in addition to any one of the first to twelfth aspects, the first gas-liquid separation membrane is a porous membrane. According to the thirteenth aspect, gas can be permeated while preventing the permeation of liquid by utilizing the porosity of the first gas-liquid separation membrane.

  According to a fourteenth aspect of the present disclosure, in addition to any one of the first aspect to the thirteenth aspect, the first gas-liquid separation membrane provides a gas generation device including a fluororesin. According to the fourteenth aspect, due to the water repellency of the fluororesin, the bubbles are likely to disappear when the bubbles come into contact with the first gas-liquid separation membrane. In addition, the first gas-liquid separation membrane has high durability.

  According to a fifteenth aspect of the present disclosure, in addition to any one of the first to fourteenth aspects, the first gas-liquid separation membrane is a water-repellent membrane. According to the fifteenth aspect, due to the water repellency of the first gas-liquid separation membrane, the bubbles are likely to disappear when the bubbles contact the first gas-liquid separation membrane.

The sixteenth aspect of the present disclosure includes
A gas generation device according to any one of the first to fifteenth aspects is provided,
By causing an electrochemical reaction in the first electrode and the second electrode in a state where the aqueous solution contained in the housing is pressurized and the liquid level of the aqueous solution is in contact with the first gas-liquid separation membrane. Provided is a gas generation method for generating gas from the aqueous solution accommodated in the casing.

  According to the sixteenth aspect, the bubbles generated in the aqueous solution in the first chamber due to the electrochemical reaction are likely to disappear after coming into contact with the first gas-liquid separation membrane as soon as they rise to the liquid level of the aqueous solution. For this reason, bubbles generated in an aqueous solution by an electrochemical reaction are unlikely to accumulate in the upper portion of the first chamber. As a result, the gas generation efficiency in the gas generator tends to increase.

  Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The following description relates to an example of the present invention, and the present invention is not limited to these. In the accompanying drawings, the XY plane is horizontal, and the positive direction of the Z axis is vertically upward.

<First Embodiment>
As shown in FIG. 1, the gas generator 1a according to the first embodiment includes a housing 10, a partition 20, a first electrode 31, a second electrode 32, a first gas-liquid separation membrane 41, a first A communication path 50 and a second communication path 51 are provided. The gas production | generation apparatus 1a produces | generates gas from aqueous solution by an electrochemical reaction. The housing 10 can store an aqueous solution. The partition wall 20 divides the internal space of the housing 10 into a first chamber 11 and a second chamber 12. The first electrode 31 is disposed in the first chamber 11. The second electrode 32 is disposed in the second chamber 12 and is electrically connected to the first electrode 31. The first gas-liquid separation membrane 41 is disposed in the first chamber 11. The first series passage 50 is a passage that communicates the first chamber 11 and the external space of the housing 10. The first series passage 50 has a first discharge port 52 that is in contact with the upper portion of the first chamber 11 above the first gas-liquid separation membrane 41. The first series passage 50 is formed by, for example, a pipe connected to the housing 10. The second communication path 51 is a second communication path 51 that connects the second chamber 12 and the external space of the housing 10. The second communication passage 51 has a second discharge port 53 that is in contact with the upper portion of the second chamber 12. The second communication path 51 is formed by, for example, a pipe connected to the housing 10. The first gas-liquid separation membrane 41 has an area larger than the cross-sectional area of the first discharge port 52.

  As shown in FIG. 1, the gas generator 1 a further includes a power source 35. The power source 35 is disposed between the first electrode 31 and the second electrode 32 and is electrically connected to the first electrode 31 and the second electrode 32. For example, the gas generating device 1a is operated in a state where an aqueous solution is accommodated in the housing 10 so that the first electrode 31 and the second electrode 32 are immersed therein. For example, a predetermined voltage difference is applied between the first electrode 31 and the second electrode 32 by the power source 35 so that the first electrode 31 functions as an anode and the second electrode 32 functions as a cathode. In this case, due to the electrolysis of water, oxygen gas is generated at the first electrode 31 that is the anode, and hydrogen gas is generated at the second electrode 32 that is the cathode. The generated oxygen gas and hydrogen gas rise as bubbles in the aqueous solution. The partition wall 20 has a function of transmitting ions in the aqueous solution and blocking the transmission of oxygen gas and oxygen gas in the aqueous solution. The partition wall 20 is made of, for example, a solid electrolyte such as a polymer solid electrolyte. As the solid electrolyte that is the partition wall 20, for example, an ion exchange membrane such as Nafion (registered trademark) can be used. For example, protons in the aqueous solution in the first chamber 11 pass through the partition wall 20 and are guided to the second electrode 32 disposed in the second chamber 12 to generate hydrogen gas.

  As the 1st electrode 31 and the 2nd electrode 32, the well-known electrode currently utilized for the electrolysis of water can be used.

  As shown in FIGS. 2A and 2B, the oxygen gas bubbles Ob generated in the first chamber 11 rise in the aqueous solution and come into contact with the first gas-liquid separation membrane 41. Thereby, a part of the interface Oi between the oxygen gas and the aqueous solution in the bubble Ob of the oxygen gas is replaced with the interface between the first gas-liquid separation film 41 and the oxygen gas, and the oxygen gas permeates the first gas-liquid separation film 41. . Thus, when the bubble Ob of oxygen gas contacts the first gas-liquid separation membrane 41, the bubble Ob disappears. In addition, since the first gas-liquid separation membrane 41 has an area larger than the cross-sectional area of the first discharge port 52, even if bubbles are generated one after another, a large number of bubbles contact the first gas-liquid separation membrane 41 within a predetermined period. Disappears. For this reason, bubbles generated in the aqueous solution due to the water electrolysis reaction are unlikely to accumulate in the upper portion of the first chamber 11. As a result, the first electrode 31 is not easily covered with bubbles, and the gas generation efficiency in the gas generation device 1a tends to be high.

The first gas-liquid separation membrane 41 typically contacts the liquid surface of the aqueous solution accommodated in the housing 10 during the operation of the gas generator 1a. For example, a gas generation method including the following steps can be performed using the gas generation device 1a.
(I) A gas generation device 1a is provided.
(Ii) An electrochemical reaction is caused in the first electrode 31 and the second electrode 32 in a state where the aqueous solution contained in the housing 10 is pressurized and the liquid surface of the aqueous solution is in contact with the first gas-liquid separation membrane 41. Thus, a gas is generated from the aqueous solution accommodated in the housing 10.

  By operating the gas generating device 1a so that the first gas-liquid separation membrane 41 is in contact with the liquid level of the aqueous solution accommodated in the housing 10, the bubbles Ob of oxygen gas generated in the aqueous solution are brought to the liquid level of the aqueous solution. As soon as it reaches, it contacts the first gas-liquid separation membrane 41 and easily disappears. For this reason, the bubble Ob of oxygen gas does not accumulate easily in the upper part of the 1st chamber 11, and the gas production | generation efficiency in the gas production | generation apparatus 1a is high.

  As shown in FIG. 1, the gas generation device 1 a further includes a pump 60, for example. The pump 60 is connected to the housing 10 by piping, and pumps the aqueous solution from an aqueous solution tank (not shown) to the internal space of the housing 10. Thereby, the 1st gas-liquid separation film | membrane 41 contacts the liquid level of the aqueous solution accommodated in the housing 10 during the driving | operation of the gas production | generation apparatus 1a. Even if the aqueous solution tank is arranged so that the internal space of the aqueous solution tank and the internal space of the housing 10 are communicated with each other by piping, and the liquid level of the aqueous solution in the aqueous solution tank is higher than the lower surface of the first gas-liquid separation membrane 41. Good. In this case, the aqueous solution stored in the housing 10 can be pressurized by the potential energy of the aqueous solution in the aqueous solution tank, and the liquid level of the aqueous solution can be brought into contact with the first gas-liquid separation membrane 41. In this case, the pump 60 may be omitted.

  The first gas-liquid separation membrane 41 is, for example, a porous membrane. In this case, the gas can be permeated while preventing the permeation of the liquid by utilizing the porosity of the first gas-liquid separation membrane 41.

When the first gas-liquid separation membrane 41 is a porous membrane, the surface tension of the aqueous solution is expressed as T [N / m], and the contact angle of the aqueous solution with respect to the surface of the first gas-liquid separation membrane 41 is θ [°]. When the constant is expressed as K [-], the difference between the pore diameter D [m] of the first gas-liquid separation membrane 41 and the differential pressure P [Pa] between the upper and lower surfaces of the first gas-liquid separation membrane 41 is as follows. The relationship is established.
P = K (T × cos θ / D)

  The constant K may vary depending on the type of the first gas-liquid separation membrane 41. However, when different membranes having the same value of the constant K are used, the pressure P is based on the above relationship in which the pressure P is inversely proportional to the pore diameter D. It is desirable to determine the hole diameter D of the gas-liquid separation membrane 41. For example, when the first gas-liquid separation membrane 41 that is a porous membrane at normal pressure is used, the first gas-liquid separation membrane 41 desirably has a pore diameter of 1 μm or less. It is desirable that the pore diameter of the first gas-liquid separation membrane 41 is determined to be ½ when the pressure P is doubled.

  The first gas-liquid separation membrane 41 includes, for example, a fluororesin. In this case, due to the water repellency of the fluororesin, when the oxygen gas bubble Ob comes into contact with the first gas-liquid separation membrane 41, the bubble Ob tends to disappear. In addition, the first gas-liquid separation membrane 41 has high durability.

  The first gas-liquid separation film 41 is, for example, a water-repellent film. In this case, due to the water repellency of the first gas / liquid separation membrane 41, when the oxygen gas bubbles Ob come into contact with the first gas / liquid separation membrane 41, the bubbles Ob tend to disappear. As the water-repellent film, for example, a film having a contact angle of 50 ° or more determined in accordance with Japanese Industrial Standard (JIS) R 3257: 1999 can be used.

  As the first gas-liquid separation membrane 41, a porous membrane of a fluororesin such as polytetrafluoroethylene can be typically used.

  As shown in FIG. 1, the gas generation device 1 a further includes a second gas-liquid separation membrane 42. The second gas-liquid separation membrane 42 is disposed below the second discharge port 53 in the second chamber 12 and has an area larger than the cross-sectional area of the second discharge port 53. In this case, when bubbles are generated in the aqueous solution by the gas generated by the electrochemical reaction in the second chamber 12, the bubbles contact the second gas-liquid separation membrane 42 before reaching the second discharge port 53. Disappear. In addition, since the second gas-liquid separation membrane 42 has an area larger than the cross-sectional area of the second discharge port 53, a large number of bubbles contact the second gas-liquid separation membrane 42 during a predetermined period even if bubbles are generated one after another. Disappears. Thereby, in the gas production | generation apparatus 1a, the production | generation efficiency of gas can be improved more reliably.

  For example, the area of the first gas-liquid separation membrane 41 is smaller than the area of the second gas-liquid separation membrane 42. For example, let us consider a case in which the first electrode 31 functions as an anode and the second electrode 32 functions as a cathode to cause an electrolysis reaction of water. The volume of hydrogen gas generated by this reaction is twice the volume of oxygen gas generated by this reaction. In this case, the oxygen gas bubbles Ob generated in the aqueous solution in the first chamber are smaller than the hydrogen gas bubbles Hb generated in the aqueous solution in the second chamber. For this reason, when fewer bubbles are generated in the first chamber than bubbles generated in the second chamber, the first gas-liquid separation membrane 41 can be made small by utilizing this fact.

  The area of the second gas-liquid separation membrane 42 is, for example, about twice the area of the first gas-liquid separation membrane 41. Further, since hydrogen molecules are smaller than oxygen molecules, they easily pass through the second gas-liquid separation membrane 42. For this reason, even when more hydrogen gas than oxygen gas is generated by electrolysis of water, the hydrogen gas easily passes through the first gas-liquid separation membrane 41 without stagnation.

  The second gas-liquid separation membrane 42 is, for example, a porous membrane, a membrane containing a fluororesin, or a water-repellent membrane, like the first gas-liquid separation membrane 41. As the second gas-liquid separation membrane 42, a porous membrane of a fluororesin such as polytetrafluoroethylene can be typically used.

  The first gas-liquid separation membrane 41 and the second gas-liquid separation membrane 42 are disposed horizontally, for example. For this reason, the whole first gas-liquid separation membrane 41 easily comes into contact with the liquid surface of the aqueous solution, and the whole second gas-liquid separation membrane 42 easily comes into contact with the liquid surface of the aqueous solution. Thereby, the bubbles rising in the aqueous solution in the first chamber 11 and the second chamber 12 are likely to directly contact the first gas-liquid separation membrane 41 or the second gas-liquid separation membrane 42 at the liquid surface. As a result, bubbles are less likely to accumulate in the upper portions of the first chamber 11 and the second chamber 12.

Second Embodiment
Next, the gas production | generation apparatus 1b which concerns on 2nd Embodiment is demonstrated. The gas generating device 1b has the same configuration as that of the gas generating device 1a unless otherwise described. Constituent elements of the gas generating apparatus 1b that are the same as or correspond to the constituent elements of the gas generating apparatus 1a are assigned the same reference numerals, and detailed descriptions thereof are omitted. The description relating to the gas generating device 1a also applies to the gas generating device 1b unless there is a technical contradiction.

  As shown in FIG. 3, the housing 10 of the gas generating device 1 b has a first inner surface 14 that faces the first electrode 31 and faces obliquely downward. The angle β formed by the plane including the lower surface of the first gas-liquid separation membrane 41 and the plane including the first inner surface 14 is a specific angle greater than 90 ° and smaller than 180 °. In this case, when the first inner surface 14 of the housing 10 faces obliquely downward, it is easy to reduce the space in which bubbles generated in the aqueous solution in the first chamber 11 accumulate. For this reason, bubbles generated in an aqueous solution due to an electrochemical reaction are unlikely to accumulate in the upper portion of the first chamber 11. As a result, the gas generation efficiency in the gas generator 1b tends to be high.

  The first gas-liquid separation membrane 41 may be inclined downward from the horizontal plane, may be inclined upward from the horizontal plane, or may extend horizontally. When the acute angle α formed by the first inner surface 14 and the horizontal plane is greater than 45 °, the angle β formed by the plane including the lower surface of the first gas-liquid separation membrane 41 and the plane including the first inner surface 14 is, for example, 225 ° −α. Can be included.

  As shown in FIG. 3, the housing 10 includes an upper outer surface 17 that is inclined downward with respect to a plane including the first inner surface 14. In addition, the angle γ formed by the upper outer surface 17 and the plane including the first inner surface 14 is greater than 90 °. In this case, it is easy to adjust the angle β formed by the plane including the lower surface of the first gas-liquid separation membrane 41 and the plane including the first inner surface 14 to an angle larger than 90 °.

  The angle β formed by the plane including the lower surface of the first gas-liquid separation membrane 41 and the plane including the first inner surface 14 is, for example, less than the angle γ formed by the upper outer surface 17 and the plane including the first inner surface 14. Thereby, when the 1st inner surface 14 of the housing | casing 10 has faced diagonally downward, it is easy to make small the space where the bubble which generate | occur | produced in the aqueous solution of the 1st chamber 11 accumulates. For this reason, bubbles generated in an aqueous solution due to an electrochemical reaction are unlikely to accumulate in the upper portion of the first chamber 11. As a result, the gas generation efficiency in the gas generator 1b tends to be high.

  For example, the first gas-liquid separation membrane 41 extends horizontally. In this case, the space in which the bubbles generated in the aqueous solution in the first chamber 11 accumulate more easily. In addition, the entire first gas-liquid separation membrane 41 tends to come into contact with the liquid surface of the aqueous solution in the first chamber 11. Thereby, it is difficult for bubbles to accumulate in the upper part of the first chamber 11, and the gas generation efficiency in the gas generation device 1 b tends to increase.

  As shown in FIG. 3, the housing 10 includes a side wall 16 having translucency, for example, and the side wall 16 defines a first inner surface 14. In addition, the first electrode 31 includes a photocatalyst. For example, when light from the light source passes through the side wall 16 and is applied to the first electrode 31, holes and electrons are generated on the surface of the first electrode 31 by the action of the photocatalyst included in the first electrode 31. . In the first electrode 31, oxygen ions in the aqueous solution are oxidized by holes to generate oxygen gas. On the other hand, protons in the aqueous solution are reduced at the second electrode 32 to generate hydrogen gas. As described above, the gas generating device 1b can generate a gas from the aqueous solution by an electrochemical reaction accompanying the light irradiation to the first electrode 31. For this reason, a power supply is unnecessary between the 1st electrode 31 and the 2nd electrode 32 in the gas production | generation apparatus 1b. The oxygen gas generated in the first chamber 11 rises as bubbles in the aqueous solution, the oxygen gas bubbles contact the first gas-liquid separation membrane 41, and only oxygen gas permeates the first gas-liquid separation membrane 41.

  Since the first inner surface 14 defined by the side wall 16 faces obliquely downward, the amount of light applied to the first electrode 31 tends to increase when the light source is located obliquely above the side wall 16 with respect to the gas generating device. Thereby, the efficiency of an electrochemical reaction and by extension, the generation efficiency of gas can be improved.

  As a light source of the light irradiated to the first electrode 31, for example, sunlight can be used. In this case, desirably, the side wall 16 is arranged such that the sum of the acute angle α formed by the first inner surface 14 and the horizontal plane and the solar altitude is 45 ° to 135 °, for example. Thereby, there is much light quantity of sunlight with which the 1st electrode 31 is irradiated.

  As shown in FIG. 3, the housing 10 further includes a lower side surface 18. The lower side surface 18 is inclined downward with respect to the plane including the first inner surface 14 and is inclined upward with respect to the horizontal plane. A part of the upper side surface 17 is formed by, for example, an upper surface panel 17 a disposed on the upper surface of the housing 10. A part of the lower side surface 18 is formed by, for example, a lower panel 18 a disposed on the lower surface of the housing 10. As shown in FIG. 4, the gas generation device 1 b is used, for example, in a state where a plurality of gas generation devices 1 b are arranged one above the other. In this case, a part of the lower outer surface 18 of the gas generating device 1b positioned above the two adjacent gas generating devices 1b is above the gas generating device 1b positioned below of the two gas generating devices 1b. It is possible to overlap a part of the outer surface 17 along the vertical direction. For this reason, when the plurality of gas generation devices 1b are arranged one above the other, the installation area of the plurality of gas generation devices 1b can be reduced. In addition, the light from the light source can be used effectively in the plurality of gas generating devices 1b.

As shown in FIG. 3, the angle θ ₁ formed by the upper outer surface 17 and the horizontal plane is smaller than the angle θ ₂ formed by the lower outer surface 18 and the horizontal plane. For this reason, the upper outer surface 17 and the lower outer surface 18 are formed so that the outer surface of the housing 10 is narrowed from the side wall 16 toward the second chamber 12. Thereby, as shown in FIG. 4, the plurality of gas generation devices 1 b are arranged so that the side walls 16 of the plurality of gas generation devices 1 b are connected in the same plane (virtual plane) at a specific inclination angle with respect to the horizontal plane. In this case, a space can be generated between the gas generators 1b adjacent to each other in the vertical direction. Thereby, the gas production | generation apparatus 1b can be arrange | positioned, without being disturbed by the gas production | generation apparatus 1b adjacent to an up-down direction. This space may be used, for example, to take out the gas generated by the gas generation device 1b.

  As shown in FIG. 3, the gas generation device 1 b includes a second gas-liquid separation membrane 42. The area of the first gas-liquid separation membrane 41 is smaller than the area of the second gas-liquid separation membrane 42. The area of the second gas-liquid separation membrane 42 is, for example, about twice the area of the first gas-liquid separation membrane 41. For example, the second gas-liquid is set so that the angle formed by the plane including the lower surface of the second gas-liquid separation membrane 42 and the plane including the first inner surface 14 is a specific angle larger than 90 ° and smaller than 180 °. A separation membrane 42 is disposed. For example, the second gas-liquid separation membrane 42 extends horizontally. The second gas-liquid separation membrane 42 may be inclined downward from the horizontal plane, or may be inclined upward from the horizontal plane. When the acute angle α formed by the first inner surface 14 and the horizontal plane is larger than 45 °, the angle formed by the plane including the lower surface of the second gas-liquid separation membrane 41 and the plane including the first inner surface 14 is, for example, 225 ° −α. May be included. The angle formed by the plane including the lower surface of the second gas-liquid separation membrane 42 and the plane including the first inner surface 14 is, for example, less than the angle γ formed by the upper outer surface 17 and the plane including the first inner surface 14.

<Third Embodiment>
Next, the gas production | generation apparatus 1c which concerns on 3rd Embodiment is demonstrated. The gas generation device 1c has the same configuration as that of the gas generation device 1a unless otherwise described. Constituent elements of the gas generating apparatus 1c that are the same as or correspond to the constituent elements of the gas generating apparatus 1a are assigned the same reference numerals, and detailed descriptions thereof are omitted. The description regarding the gas generation device 1a also applies to the gas generation device 1c as long as there is no technical contradiction.

  As shown in FIGS. 5-7, the inner surface of the housing | casing 10 of the gas production | generation apparatus 1c contains the 1st guide surface 19a. The first guide surface 19 a extends obliquely upward from the specific position of the first chamber 11 located below the first gas-liquid separation membrane 41 toward the first gas-liquid separation membrane 41. In this case, bubbles generated in the aqueous solution in the first chamber 11 rise toward the first gas-liquid separation membrane 41 along the first guide surface 19a. Thus, the bubbles are guided to the first gas-liquid separation membrane 41 by the first guide surface 19a. Thereby, it is hard for a bubble to stay in the specific location of the 1st chamber 11, and the gas production | generation efficiency in the gas production | generation apparatus 1c tends to become high.

  As shown in FIG. 6, the first chamber 11 includes, for example, a space defined by a pair of inner surfaces of the housing 10 facing each other in a direction perpendicular to the partition wall 20 above the partition wall 20. The first gas-liquid separation membrane 41 is fixed to the pair of inner surfaces in this space.

  As shown in FIGS. 5 and 7, the gas generation device 1 c includes a second gas-liquid separation membrane 42. The area of the first gas-liquid separation membrane 41 is smaller than the area of the second gas-liquid separation membrane 42, for example. The area of the second gas-liquid separation membrane 42 is, for example, about twice the area of the first gas-liquid separation membrane 41. As shown in FIG.5 and FIG.6, the inner surface of the housing | casing 10 of the gas production | generation apparatus 1c contains the 2nd guide surface 19b. The second guide surface 19 b extends obliquely upward toward the second gas-liquid separation membrane 42 from a specific position of the second chamber 12 located below the second gas-liquid separation membrane 42. Thereby, the bubbles generated in the aqueous solution in the second chamber 12 rise toward the second gas-liquid separation membrane 42 along the second guide surface 19b. As described above, the bubbles are guided to the second gas-liquid separation membrane 42 by the second guide surface 19b. Thereby, it is hard for a bubble to stay in the specific location of the 2nd chamber 12, and the production | generation efficiency of the gas in the gas production | generation apparatus 1c tends to become high.

  As shown in FIG. 7, the second chamber 11 includes, for example, a space defined by a pair of inner surfaces of the housing 10 facing each other in a direction perpendicular to the partition 20 above the partition 20. The second gas-liquid separation membrane 42 is fixed to the pair of inner surfaces in this space. The first gas-liquid separation membrane 41 and the second gas-liquid separation membrane 42 are arranged in the horizontal direction (Y-axis direction) along the main surface of the partition wall 20 above the partition wall 20. Thereby, it is easy to make the dimension of the direction perpendicular | vertical to the partition 20 of the gas production | generation apparatus 1c small. As shown in FIG. 5, for example, a partition wall 15 is formed in the internal space of the housing 10. The partition wall 15 partitions the space above the first guide surface 19 a of the first chamber 11 and the space above the second guide surface 19 b of the second chamber 12 in the horizontal direction along the main surface of the partition wall 20. ing.

  The gas generator of the present disclosure can generate hydrogen by electrolyzing water, and can be applied to small-scale household hydrogen generation or large-scale hydrogen generation plants.

DESCRIPTION OF SYMBOLS 10 Case 11 1st chamber 12 2nd chamber 14 1st inner surface 16 Side wall 17 Upper outer surface 18 Lower outer surface 19a First guide surface 20 Partition 31 First electrode 32 Second electrode 41 First gas-liquid separation membrane 42 Second gas Liquid separation membrane 50 First series passage 51 Second communication passage 52 First discharge port 53 Second discharge port 1a to 1c Gas generating device

Claims (16)

A gas generating device that generates gas from an aqueous solution by an electrochemical reaction,
A housing capable of containing the aqueous solution;
A partition partitioning the internal space of the housing into a first chamber and a second chamber;
A first electrode disposed in the first chamber;
A second electrode disposed in the second chamber and electrically connected to the first electrode;
A first gas-liquid separation membrane disposed in the first chamber;
A first series passage that communicates the first chamber with an external space of the housing, and has a first discharge port that is in contact with the upper portion of the first chamber above the first gas-liquid separation membrane. A first series of passages;
A second communication path for communicating the second chamber and the outer space of the housing, the second communication path having a second discharge port in contact with the upper portion of the second chamber,
The first gas-liquid separation membrane has an area larger than the cross-sectional area of the first discharge port.
Gas generator.   2. The gas generation device according to claim 1, wherein the first gas-liquid separation membrane is in contact with a liquid surface of the aqueous solution accommodated in the housing during operation of the gas generation device.   A second gas-liquid separation membrane disposed below the second discharge port in the second chamber, further comprising a second gas-liquid separation membrane having an area larger than a cross-sectional area of the second discharge port. The gas generation device according to claim 1 or 2.   The gas generating device according to claim 3, wherein an area of the first gas-liquid separation membrane is smaller than an area of the second gas-liquid separation membrane. The housing has a first inner surface facing the first electrode and facing obliquely downward,
The angle β formed by the plane including the lower surface of the first gas-liquid separation membrane and the plane including the first inner surface is a specific angle larger than 90 ° and smaller than 180 °. The gas generating device according to claim 1. The housing includes an upper outer surface inclined downward with respect to a plane including the first inner surface,
The gas generation device according to claim 5, wherein an angle γ formed by the upper outer surface and a plane including the first inner surface is greater than 90 °.   The angle β formed by the plane including the lower surface of the first gas-liquid separation membrane and the plane including the first inner surface is equal to or less than the angle γ formed by the upper outer surface and the plane including the first inner surface. The gas generating device described.   The gas generation device according to claim 5, wherein the first gas-liquid separation membrane extends horizontally. The housing includes a side wall defining the first inner surface and having translucency,
The gas generation device according to claim 5, wherein the first electrode includes a photocatalyst. The housing further includes a lower outer surface inclined downward with respect to a plane including the first inner surface and inclined upward with respect to a horizontal plane,
When the plurality of gas generating devices are arranged one above the other, a part of the lower outer surface of the gas generating device located above among the two adjacent gas generating devices is below the two gas generating devices. The gas generating device according to any one of claims 6 to 9, wherein the gas generating device can overlap with a part of the upper outer surface of the gas generating device positioned along the vertical direction.   The gas generating device according to claim 10, wherein an angle formed by the upper outer surface and a horizontal plane is smaller than an angle formed by the lower outer surface and a horizontal plane.   The inner surface of the casing includes a first guide surface extending obliquely upward from the specific position of the first chamber located below the first gas-liquid separation membrane toward the first gas-liquid separation membrane. The gas production | generation apparatus of any one of Claims 1-11 containing.   The gas generator according to any one of claims 1 to 12, wherein the first gas-liquid separation membrane is a porous membrane.   The gas generation device according to claim 1, wherein the first gas-liquid separation membrane includes a fluororesin.   The gas generator according to any one of claims 1 to 14, wherein the first gas-liquid separation membrane is a water-repellent membrane. A gas generation device according to any one of claims 1 to 15 is provided,
By causing an electrochemical reaction in the first electrode and the second electrode in a state where the aqueous solution contained in the housing is pressurized and the liquid level of the aqueous solution is in contact with the first gas-liquid separation membrane. A gas generation method for generating gas from the aqueous solution contained in the housing.

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