Method and apparatus for producing hydrogen gas

Abstract

To provide a method for producing a hydrogen gas, which enables the production of a hydrogen gas with high energy efficiency.SOLUTION: This method for producing a hydrogen gas includes: placing water between electrodes; and allowing pulsed discharge to occur between the electrodes to decompose water molecules, thereby generating the hydrogen gas. In the method, the frequency for the pulsed discharge is 190-196 kHz or a double vibration frequency thereof.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method and an apparatus for producing hydrogen gas. In particular, the present invention relates to a method and an apparatus for producing hydrogen gas that can generate hydrogen gas with high energy efficiency using standing waves in the high-frequency region with water as a raw material.

Background Art

[0002] Hydrogen gas is expected as an energy source for realizing a decarbonized society because it only produces water when burned and does not emit carbon dioxide. As an industrial method for producing hydrogen gas, the method of obtaining it by electrolyzing water is the most common method. However, the electric power used in electrolysis is still mainly derived from fossil energy, and the environmental load in the process of producing hydrogen gas is an important issue.

[0003] Patent Document 1 (Japanese Patent Application Laid-Open No. 2007-314384) discloses a method for producing hydrogen gas characterized by irradiating water only with infrared rays having a wavelength of 2.8 μm or more and 3.2 μm or less. According to the invention, it is possible to produce hydrogen gas, which will be widely used as fuel for future fuel cells, only by irradiating water with far-infrared rays contained in sunlight without requiring thermal or electrical energy, and it is also possible to efficiently utilize sunlight.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the decomposition of water molecules using sunlight, there are constraints that the supply of sunlight is unstable and the device size cannot be avoided from increasing to secure the light-receiving area. In addition, only specific wavelengths contained in sunlight rays are involved in the decomposition of water molecules, so there is a problem of low energy efficiency.

[0006] The present invention has been completed in view of the above problems, and an object of one embodiment is to provide a method for producing hydrogen gas that can generate hydrogen gas with high energy efficiency. Another object of the present invention is to provide a hydrogen gas production apparatus suitable for such a hydrogen gas production method and capable of being miniaturized.

Means for Solving the Problems

[0007] As a result of intensive studies by the present inventors, it has been found that by applying a standing wave in a specific high-frequency region to water molecules, the bond of the OH group of water molecules can be dissociated and hydrogen gas can be efficiently generated. The present invention has been completed based on the above findings and is exemplified below.

[0008] [1] A method for producing hydrogen gas, comprising disposing water between electrodes and decomposing water molecules by applying pulsed discharge between the electrodes to generate hydrogen gas, wherein the frequency of the pulsed discharge is 190 to 196 kHz or its harmonic frequency. [2] The method for producing hydrogen gas according to [1], wherein the electrodes consist of a discharge electrode and a ground electrode, the discharge electrode is disposed in insulating oil on the water surface, and the ground electrode is disposed in water. [3] The method for producing hydrogen gas according to [1] or [2], further comprising applying a magnetic field to the water. [4] A hydrogen gas production apparatus, comprising a resonant transformer and a hydrogen generation device, wherein the hydrogen generation device has a water-containing portion isolated between electrodes, and the resonant transformer is configured to apply pulsed discharge between the electrodes. A hydrogen gas production apparatus, wherein the frequency of the pulsed discharge is 190 - 196 kHz or its harmonic frequency. [5] The hydrogen gas production apparatus according to [4], wherein the electrodes consist of a discharge electrode and a ground electrode. [6] The hydrogen gas production apparatus according to [4] or [5], further comprising a magnetic field applying means arranged to surround the water containing portion.

Advantages of the Invention

[0009] According to one embodiment of the present invention, it is possible to provide a method for producing hydrogen gas with high energy efficiency. According to another embodiment of the present invention, it is possible to provide a hydrogen gas production apparatus suitable for such a method for producing hydrogen gas and capable of miniaturization.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0011] Next, embodiments of the present invention will be described with reference to the drawings. It should be understood that the present invention is not limited to the following embodiments, and that design changes, improvements, etc. can be appropriately made based on the ordinary knowledge of those skilled in the art without departing from the spirit of the present invention.

[0012] Figure 1 shows the flow of a method for producing hydrogen gas according to an embodiment of the present invention. The high-voltage, high-frequency pulsed discharge generated by the resonant transformer 1 is transmitted to the electrode 4 of the hydrogen generation device 3 through the conducting wire 2. As a result, the molecules of water 6 disposed between the electrode 4 and the ground 8 are excited, dissociation of the OH covalent bond occurs, and thereby hydrogen gas is generated. The ground 8 is installed to stabilize the discharge direction. Instead of the ground 8 which is a ground electrode, it may be an electrode connected to the resonant transformer 1 by another conducting wire.

[0013] Here, it is important that the frequency of the pulsed discharge is 190 - 196 kHz or its harmonic frequency. That is, substances have unique energy levels and each has an absorption spectrum, and when the applied vibration (energy) is large, the substance transitions to an excited state. In order to dissociate the OH covalent bond of water molecules with small energy, it is necessary to construct a condition in which a standing wave is formed in the vibration of water molecules and cause an excited state.

[0014] Referring to Figure 4, an effective frequency graph in the excitation of water molecules is shown. The graph is a graph of the IR spectrum of the three degrees of freedom of water molecules, the horizontal axis is the frequency of the pulsed discharge, and the vertical axis is the molar extinction coefficient. Among these, the value of the one-degree-of-freedom vibration is the largest, and the approximation of that value is 1737 cm -1 (frequency 52 THz) as a theoretical value. In order to vibrate and resonate water molecules, the frequency or its lower harmonic is effective. As a result, the excitation of the vibrationally excited water molecules progresses and the covalent bond is broken. According to the findings of the present inventors, 190 - 196 kHz or its harmonic frequency is a frequency that can vibrate water molecules with realistic and high energy efficiency. The harmonic frequency means a frequency that is an integer multiple of any frequency within the frequency range.

[0015] The resonance transformer 1 is not particularly limited as long as it can perform pulse discharge under the above conditions. As an example, it includes a Tesla coil. When the resonance transformer 1 is connected to an external power source (for example, 100 V), an alternating current flows through the primary coil. As a result of electromagnetic induction by the generated oscillating magnetic field, an alternating current flows through the secondary coil. The amount of energy during pulse discharge is not particularly limited, and a resonance circuit in which discharge oscillation is excited is sufficient.

[0016] The electrode 4, which is a discharge electrode, may be disposed in the water 6, but from the viewpoints of discharge stability and prevention of ignition of the generated hydrogen gas, it is preferably disposed in the insulating oil 5 on the water surface of the water 6. The type of the insulating oil 5 is not particularly limited, and for example, silicone oil can be used.

[0017] Furthermore, when performing pulse discharge, it is preferable to apply a magnetic field to the water 6 using a magnetic field applying means. By applying a magnetic field, the electron spins in oxygen can be aligned in the same direction, so that the water molecules can be vibrated more efficiently. The method of applying the magnetic field is not particularly limited, and examples include a method of disposing an annular magnet around the water 6 or a method of disposing a wire coil around the water 6 and energizing it.

[0018] FIG. 2 is a front schematic view of the hydrogen generation device 3 in an embodiment of the present invention, and FIG. 3 is a top schematic view of the hydrogen generation device 3 in an embodiment of the present invention. The hydrogen generation device 3 has a water-containing portion isolated between the electrode 4, which is a discharge electrode, and the ground 8, which is a ground electrode. An annular neodymium (NdFeB) magnet 7 is disposed around the water-containing portion.

[0019] When the water-containing portion of the hydrogen generation device 3 is filled with water 6 and further the insulating oil 5 is laid on the water surface, the electrode 4 is disposed in the insulating oil 5 and the ground 8 is disposed in the water 6. Thereby, the pulse discharge is stabilized and ignition of the generated hydrogen gas can be suppressed.

[0020] The mixed gas of hydrogen and oxygen generated by the above method and apparatus can be collected using a pipe or the like due to the pressure difference between the inside and outside of the apparatus. When separation of hydrogen and oxygen is required, a polymer membrane can be disposed in the collection path.

Example

[0021] Examples of the present invention are shown below. These examples are provided to better understand the present invention and its advantages, and are not intended to limit the invention.

[0022] The hydrogen generation apparatus 3 shown in FIGS. 2 and 3 was filled with insulating oil 5 and water 6, and pulsed discharge was performed from the electrode 4 using the resonance transformer 1. The volume of the filled water 6 was 120 cc. The energy during pulsed discharge was 100 V and 2 A. Vibration was applied at different frequencies for 10 minutes each, and the volume of the reacted water 6 (i.e., the decrease in the volume of water 6) was recorded. The results are shown in FIG. 5.

[0023] As shown in FIG. 5, with respect to the vibration frequency (kHz) on the horizontal axis, the reaction volume (cc) of water on the vertical axis was confirmed in the range of 190 to 196 kHz, and was maximum near 193 kHz. Therefore, it was confirmed that by performing pulsed discharge in the range of 190 to 196 kHz, water molecules can be decomposed to generate hydrogen gas. Also, since it is possible to excite water molecules by the same principle even at the double vibration frequency of any frequency within the range of 190 to 196 kHz, it is presumed that these double vibration frequencies can also be used.

Industrial Applicability

[0024] According to the present invention, hydrogen gas can be produced with high energy efficiency by intensively performing pulsed discharge at a frequency effective for dissociating the OH covalent bond of water molecules. Also, since the apparatus for performing pulsed discharge can be realized in a small size, miniaturization of the entire hydrogen gas production apparatus is possible.

Explanation of Reference Numerals

[0025] 1 Resonance transformer 2 Conducting wire 3 Hydrogen generation device 4 Electrode 5 Insulating oil 6 Water 7 Neodymium magnet 8 Ground

Claims

1. The method includes disposing water between electrodes and subjecting the electrodes to pulse discharge to decompose water molecules and generate hydrogen gas; The method for producing hydrogen gas, wherein the frequency of the pulse discharge is 190 to 196 kHz or a harmonic frequency thereof.

2. 2. The method for producing hydrogen gas according to claim 1, wherein the electrodes comprise a discharge electrode and a ground electrode, the discharge electrode being disposed in insulating oil above the water surface, and the ground electrode being disposed underwater.

3. The method for producing hydrogen gas according to claim 1 or 2, further comprising applying a magnetic field to the water.

4. A hydrogen gas production apparatus, comprising: A resonant transformer and a hydrogen generating device are included. the hydrogen generator has a water containing portion isolated between electrodes, the resonant transformer configured to pulse discharge between the electrodes; The frequency of the pulse discharge is 190 to 196 kHz or a harmonic frequency thereof.

5. 5. The hydrogen gas production apparatus according to claim 4, wherein the electrodes comprise a discharge electrode and a ground electrode.

6. 6. The hydrogen gas producing apparatus according to claim 4, further comprising a magnetic field applying means disposed so as to surround the water storage portion.

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