Water decomposition method and heat pump method with cavitation being generated in water under condition that active oxygen is hardly generated

Abstract

To provide a method for promoting generation of atomic hydrogen (active hydrogen) by generating cavitation when fine bubble burst in water by a fine bubble generator, under a condition that active oxygen is hardly generated in water.SOLUTION: There is provided a method for generating dissolved hydrogen water which is included in fine bubbles accompanying reaction for reducing proton and metal cation by reduction force of the atomic hydrogen, and heat generation, and hardly moves out into the atmosphere, by decomposing water in a state in which generation of active oxygen is suppressed by cavitation by optimizing materials, shapes, lifts, flow rates of a nozzle and a submersible pump for generating fine bubbles and a shape of a reaction container, thereby promoting generation of atomic hydrogen.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This is a technical field that decomposes water without heating or electrolysis. It is also a technical field that generates cavitation by generating fine bubbles in water at room temperature and pressure under conditions that make it difficult to generate active oxygen, and then decomposes water using the generated cavitation. This is a technical field that uses the chemical reaction of atomic hydrogen and active oxygen caused by water decomposition by cavitation, and the reverse reaction, in which atomic hydrogen and active oxygen combine to produce water and heat, through oxidation-reduction. + This is a technological field that converts hydrogen, which is produced by reducing metal cations, into electrical energy and thermal energy for use. [Background technology]

[0002] Well-known methods for producing hydrogen by decomposing water include thermal decomposition, electrolysis, and steam reforming. Because thermal decomposition of water requires heat of over 1000°C, "thermochemical methods" for producing hydrogen by recycling and reusing the water through chemical reactions (such as oxidation-reduction reactions that combine halogens such as chlorine and boron with metal materials) have been under investigation for over 50 years. Recently, the Bunsen reaction, which combines iodine and sulfur dioxide with electrolysis, has become the mainstream of research. However, practical application still faces challenges in terms of thermal efficiency, economy, and stability (Non-Patent Document 1). The electrolysis method faces the challenge of high costs for platinum electrodes and oxygen and hydrogen separation membranes. Steam reforming, which uses fossil fuels as raw materials and operates at reaction temperatures of over 500°C, poses challenges from the perspective of reducing carbon dioxide emissions.

[0003] Sonochemistry is a technology that induces chemical reactions in high-temperature and high-pressure fields caused by the energy of cavitation generated in water irradiated with ultrasound (Non-Patent Document 2). Cavitation occurs when microscopic bubbles generated by ultrasound irradiation expand and grow while expanding and contracting, and burst when they are unable to withstand the surrounding pressure. The energy generated by this cavitation is said to reach several thousand degrees and several thousand atmospheres in an instant, and is known to cause cracks and breakage in motorboat propellers. This can be confirmed by placing aluminum foil under an ultrasonic cleaner, where holes are quickly created. Ultrasonic cavitation generates highly oxidizing radicals (reactive oxygen species; OH·, O·2 - , O·, H2O2) is produced, so in addition to cleaning, it is also used for the oxidative decomposition of organic matter.

[0004] It is known that cavitation occurs when microscopic bubbles generated by a fine bubble generator burst, and this has been applied to cleaning, but there are no known examples of fine bubbles being used alone in chemical reactions such as the oxidative decomposition of organic matter. It is known, however, that the combined use of ultrasound and fine bubbles can enhance the oxidative decomposition of organic matter achieved by ultrasound alone. However, even when using methods such as irradiating ultrasound or applying fine bubbles to water, there are no known reports that hydrogen can be generated by promoting the generation of atomic hydrogen and suppressing the generation of active oxygen when water is decomposed by cavitation. [Non-Patent Document 1] Elements 6: Hydrogen, by Kenji Ichimura, Kenseisha, 1999. [Non-patent document 2] The Story of Sonoprocess, Yasuo Iida, Nikkan Kogyo Shimbun, 2006. [Patent documents]

[0005] Patent Document 1 discloses a method in which an AC voltage is applied to a high-frequency generating electrode. However, the energy used to split water is generated by underwater plasma generated by the applied voltage. Patent Document 2 discloses an atomization method in which hydrogen gas is injected into the body and then electrolyzed. Patent Document 3 describes a method in which atomic hydrogen is generated in the atmosphere by irradiating a mixture of hydrogen gas and an inert gas with light. Both of these methods differ from the present method, which relies on cavitation of fine bubbles generated in water. [Patent Document 1] Patent Publication No. 2021-502898 [Patent Document 2] Patent Publication No. 2017-077312 [Patent Document 3] JP 2007-329307 Public Relations Summary of the Invention [Problem to be solved by the invention]

[0006] To provide a method for promoting the generation of atomic hydrogen (active hydrogen) by generating cavitation using fine bubbles under conditions that make it difficult to generate active oxygen in water.

[0007] In the method of decomposing water by electrolysis, oxygen molecules and atomic oxygen are thought to be generated on the surface of the anode electrode, and hydrogen molecules and atomic hydrogen (sometimes called active hydrogen) are thought to be generated on the surface of the cathode. However, active oxygen is also thought to be generated at the same time, and it is thought that the generated atomic hydrogen reacts with the active oxygen, oxygen molecules, and oxygen atoms to return to water and maintain a reduced state, which is difficult to achieve. Water can also be decomposed by cavitation caused by generating fine bubbles in water using ultrasound or a fine bubble generator. Even if hydrogen molecules and hydrogen atoms are generated as in electrolysis, active oxygen is also generated at the same time. Therefore, the generated hydrogen and atomic hydrogen are thought to quickly disappear, making it impossible to maintain a reduced state. Active oxygen is particularly likely to be generated when the ultrasonic generator or fine bubble generator is made of a metal such as stainless steel. The applicants used an oxidation-reduction potentiometer to measure the oxidation-reduction potential of water generated using an ultrasonic cleaner or a stainless steel pump, and confirmed that the oxidation-reduction potential either remained unchanged or increased.

[0008] The results are as follows when ultrasonic waves or fine bubbles are applied to water added to a standard stainless steel container [Non-Patent Document 2]. Note that · represents an electron, H· represents atomic hydrogen, and OH· and O· represent the reactive oxygen species hydroxyl radical and oxygen atom, respectively. [ka] [ka] [ka] [ka] [ka] [ka]

[0009] When ultrasonic waves or fan bubbles are generated in water added to the plastic container of this invention, the oxidation-reduction potential drops to between -200mV and -500MV, and the dissolved oxygen concentration drops from the initial 8mg / L to around 1mg / L. This suggests that the production of atomic hydrogen exceeds the production of active oxygen, and that the active oxygen is eventually converted into water by the atomic hydrogen and eliminated. As a result, the following chemical reaction is thought to occur: In addition to [Chemical formula 3], the reaction [Chemical formula 7], in which hydrogen is produced by the reduction of protons by atomic hydrogen, also occurs in water, which is particularly rich in protons. [ka]

[0010] Furthermore, in alkaline water with dissolved alkali metals or alkaline earth metals, atomic hydrogen H· is thought to reduce metal cations and cause atomization reactions. When calcium hydroxide is dissolved in water, the following chemical reaction is thought to occur, resulting in the production of hydrogen. The intermediate product CaO is thought to be involved in the generation of heat of hydration. The inventors have confirmed the presence of CaO through analysis, but the production of unconfirmed products such as Ca2O and CaO2 is also possible [Chemical Formulas 8, 9, 10]. In the case of sodium hydroxide, the production of Na2O and Na2O2 is thought to occur [Chemical Formulas 11, 12].

[0011] Metal cations (e.g., calcium hydroxide Ca(OH)2, sodium hydroxide NaOH) [ka] [ka] [ka] [ka] [ka] On the other hand, in water that has dissolved organic or inorganic acids, protons are reduced by atomic hydrogen to generate hydrogen. Chemical reactions such as the decomposition of organic matter have not been confirmed.

[0012] Inorganic acids (e.g., hydrochloric acid HCl, phosphoric acid H3PO4) [ka] [ka] Organic acid example) acetic acid CH3COOH [ka]

[0013] Specific examples of alkali metals include their hydroxides, LiOH, NaOH, and KOH. Suitable alkaline earth metals include Be(OH)2, Mg(OH)2, Ca(OH)2, and Ba(OH)2, although other metals may also be used. Examples of organic acids include, but are not limited to, acetic acid, various amino acids, citric acid, L-ascorbic acid, malic acid, succinic acid, fumaric acid, lactic acid, butyric acid, propionic acid, oxalic acid, formic acid, and various fatty acids. Examples of inorganic acids include, but are not limited to, hydrochloric acid, sulfuric acid, nitric acid, boric acid, carbonic acid, and phosphoric acid. Compounds of these acids may also be used. Other examples of water include seawater, natural carbonated water, carbonated hot spring water, and aqueous ammonia (ammonium). Carbonic acid By applying fine bubbles directly to hot spring water, it can be used to create a hydrogen water bath, or it can be used to generate hydrogen or generate electricity. Low-temperature hot spring water can also be used to warm the water by utilizing the heat generated. Furthermore, hydrogen-generating materials can be made from organic acids, inorganic acids, sodium carbonate, sodium bicarbonate, etc., and hydrogen can be generated by applying fan bubbles to water to which this material has been added. The reducing power of atomic hydrogen can also be used to reduce substances or prevent oxidation. Hydrogen-generating materials can also be used as bath additives. Meanwhile, phosphoric acid is found in high concentrations in sewage and sewage sludge, and phosphoric acid recovered from sewage can be used to generate hydrogen or converted into thermal or electrical energy for use. [Means for solving the problem]

[0014] After extensive research, the proposers have discovered that by optimizing the material, shape, head, flow rate, and shape of the reaction vessel and nozzle and submersible pump used to generate fine bubbles, they can promote the production of raw hydrogen by decomposing water in a manner that suppresses the generation of active oxygen caused by cavitation. Atomic hydrogen converts active oxygen into water and heat, and because the hydrogen molecules are encapsulated in the fine bubbles and are difficult to burst, they can be sustainably stored as dissolved hydrogen water in the water, and they have developed a method for creating water that maintains the reducing power of atomic hydrogen.

[0015] The pump housing, nozzle, and reaction vessel used to generate fine bubbles are made of plastic. Suitable plastic materials include polystyrene, polypropylene, Teflon, fiber-reinforced plastic, ABS resin (acrylonitrile butadiene styrene), vinyl chloride, polyethylene, polyethylene terephthalate, and polylactic acid, but there are no particular restrictions as long as they are made of plastic. If the water has an alkaline or acidic pH, durable materials such as FRP and Teflon are preferred.

[0016] The most preferable shape of the reaction vessel is cylindrical, but there is no particular restriction on the shape.

[0017] The most preferred pump is a submersible throw-in pump, but this is not a limitation.In terms of pump specifications, it is most preferred that the total head be 10m or more, but it can be 6m or more depending on the size of the reaction vessel and the volume of water.The most preferred flow rate (discharge rate) is 100L / min or more, but it may be less depending on the size of the reaction vessel and the volume of water.It is preferred that the pump's water intake port be located below the reaction vessel, and that the pump's water outlet be located at the top of the reaction vessel, facing up towards the vessel, but this is not a limitation. [Effects of the Invention]

[0018] When fine bubbles are used to generate cavitation under conditions that make it difficult for active oxygen to be generated in water, the generation of atomic hydrogen can be increased through water decomposition caused by cavitation. When a large amount of atomic hydrogen is generated, active oxygen can be converted into water, and two atomic hydrogen atoms combine to produce hydrogen molecules, hydrogen is produced by proton reduction, metal cations are reduced by atomic hydrogen and the reduced metal atoms decompose water to produce hydrogen and oxygen, and the oxygen produced produces metal oxides. Furthermore, the generated atomic hydrogen reacts with reactive oxygen species such as OH· to produce water and heat, and the heat generated can be used as a heat pump. In alkaline water, the generated metal oxides generate heat through hydration, and this heat can also be used as a heat pump. Metal cations are reduced by atomic hydrogen and become atomized, and the atomized metal decomposes water to produce hydrogen and oxygen. The oxygen produced quickly combines with the metal atoms to form an oxide, so only hydrogen is produced. In organic acid solutions and inorganic acid solutions that contain a large number of protons, the protons are reduced by atomic hydrogen, producing hydrogen but not oxygen. Therefore, this method can inexpensively produce hydrogen from water without using expensive platinum or oxygen and hydrogen separation membranes. Furthermore, hydrogen water can be used directly in a wet methanol fuel cell to generate electricity. Furthermore, by using hydrogen water as a diluent for methanol fuel cells, it is possible to maintain high voltage and generate electricity even when the amount of methanol is reduced, which can contribute to improving the fuel consumption rate of methanol fuel cells. Therefore, this technology can simultaneously generate three forms of energy: hydrogen fuel, thermal energy, and electrical energy. [Brief explanation of the drawings]

[0019] [Figure 1] This graph shows the changes over time in water temperature (°C), dissolved oxygen concentration (μg / L), and oxidation-reduction potential (ORP) (mV) for a 10 mM sodium hydroxide solution at water temperatures of 10°C, 20°C, and 30°C. [Figure 2] This photograph confirms the generation of hydrogen into the atmosphere when the water surface of a reaction vessel containing 10 mM sodium hydroxide solution is ignited with a lighter at a water temperature of 20°C. [Figure 3] This graph shows the change in water temperature over time when tap water at a temperature of 20°C is reacted in a sealed container that prevents heat from escaping into the air, and when it is reacted in an open container that allows heat to escape into the air. [Figure 4]This figure shows the maximum hydrogen concentration when hydrogen is generated in a solution with an initial water temperature of 18°C ​​for 10 mM each of barium hydroxide, calcium hydroxide, potassium hydroxide, lithium hydroxide, and sodium hydroxide. [Figure 5] This graph shows the maximum hydrogen concentration when hydrogen is generated in solutions of the following: Seto Inland Sea seawater, 10 mM ammonia water, 10 mM ammonium acetate, 8 mM nitric acid, 10 mM hydrochloric acid, 10 mM boric acid, 10 mM phosphoric acid, 10 mM sodium phosphate, 10 mM disodium hydrogen phosphate, and 10 mM sodium dihydrogen phosphate, with an initial water temperature of 18°C. [Figure 6] This figure shows the maximum hydrogen concentration when hydrogen is generated in a solution of 10 mM organic acid with an initial water temperature of 18°C. The organic acids used were sodium carbonate, sodium bicarbonate, acetic acid, formic acid, sodium formate, lactic acid, citric acid, succinic acid, malic acid, fumaric acid, oxalic acid, butyric acid, propionic acid, L-ascorbic acid, glycine, L-methionine, and monosodium L-glutamate. [Figure 7] The graph shows the maximum hydrogen concentration when hydrogen is generated in 10 L of natural carbonated hot spring water at 18°C, 10 g of commercially available bath salts containing sodium carbonate, 10 g of commercially available bath salts containing sodium bicarbonate, 10 mM sodium carbonate reagent, and 10 mM sodium bicarbonate reagent solution. [Figure 8] This figure shows the voltage values ​​when generating electricity in a methanol fuel cell by diluting the methanol concentration with the generated hydrogen water to 0.25M, 0.5M, and 1.0M. [Figure 9] This diagram shows the structure of a bubble generator that is designed to prevent the generation of reactive oxygen species, and the flow of water when cavitation occurs due to bubbles. DETAILED DESCRIPTION OF THE INVENTION

[0020] Example 1) A 10 mM sodium hydroxide solution was prepared by adding 10 L of tap water or ultrapure water to a 15 L polypropylene container and leaving it overnight in a thermostatic bath at 10 to 30°C. The next day, the bubble generator was turned on and the dissolved hydrogen (DH), oxidation-reduction potential (ORP), water temperature, and ambient air temperature were recorded. The bubble generating nozzle used was the S.BT-50S from Bubble Tank Co., Ltd. The submersible pump used was the Pondy SM625X from Koshin Co., Ltd. For open systems where heat escapes to the outside air, a 15 L cylindrical or box-shaped polypropylene container was used as the reaction vessel. For closed systems where the outside air does not escape, the open container was placed in a thick cylindrical container that was further sealed with a lid. Figure 1 shows the changes over time in water temperature (°C), dissolved oxygen concentration (μg / L), and oxidation-reduction potential (ORP) (mV) when the water temperature is 10°C, 20°C, and 30°C in a 10 mM sodium hydroxide solution.

[0021] Example 2) Methanol fuel was prepared by diluting stock methanol solution with hydrogen water generated using this method with 100 mM sodium hydroxide solution, or with ultrapure water, to a concentration of 0.25M to 1.0M. The prepared methanol fuel was poured into a methanol fuel cell, and the voltage and current were immediately measured. The methanol fuel cell used was a Megachem 357E (maximum voltage 0.6V, output 10mW). Figure 7 shows the voltage values ​​obtained when generating electricity by diluting the methanol concentration of the methanol fuel cell with the generated hydrogen water to 0.25M, 0.5M, and 1.0M. For comparison, the voltage values ​​obtained when diluted with ultrapure water are shown.

Claims

1. This method generates cavitation in water using fan bubbles to generate atomic hydrogen H. The atomic hydrogen then reduces active oxygen, generating water and heat. The method involves the following steps: A fine bubble generator is used to generate fine bubbles in water under conditions that make it difficult to generate active oxygen species such as OH. The water is decomposed by cavitation caused when the generated fan bubbles burst. The decomposition of water generates atomic hydrogen and active oxygen, but the generation of atomic hydrogen is promoted, and the generation of atomic hydrogen exceeds the generation of active oxygen, causing the active oxygen to be reduced by the atomic hydrogen, generating water and heat.

2. The conditions under which active oxygen is less likely to be generated as described in claim 1 are that the nozzle of the fine bubble generator used to generate fine bubbles and the pump housing used to supply water to the nozzle are made of various plastics (polystyrene, polypropylene, Teflon, fiber-reinforced plastic, acrylonitrile butadiene styrene, vinyl chloride, polyethylene, polyethylene terephthalate, or polylactic acid).

3. When using a fine bubble generator made of the material of claim 2, the pump specifications to be used are a submersible throw-in pump with a total head of 10m or more, most preferably 10m or more, but can be 6m or more depending on the size of the reaction vessel and the volume of water, a flow rate (discharge rate) of 100L / min or more, most preferably 100L / min or more, but can be less depending on the size of the reaction vessel and the volume of water, the water intake port should be located below the reaction vessel, and the pump water outlet should be located at the top of the reaction vessel, preferably facing up towards the vessel.

4. The chemical reaction vessel used to generate cavitation under conditions that make it difficult to generate active oxygen as described in claim 1 using a fine bubble generator made of the material described in claim 2 is most preferably cylindrical, followed by a rectangular parallelepiped.Furthermore, it is most desirable for the water flow in the vessel to be concentrically structured from the top of the vessel (the pump's outlet) to the bottom (the pump's inlet), with the pump located at the center of the vessel.

5. This method uses a fine bubble generator made of the material described in claim 2 on water (tap water, distilled water, or ultrapure water) to generate water and heat by combining atomic hydrogen generated by the decomposition of water by the cavitation described in claim 1 with active oxygen species such as OH., and also generates hot water heated by the generated heat.

6. This method uses a fine bubble generator made of the material of claim 2 to generate alkaline water, and by carrying out claim 1, the atomic hydrogen generated reduces metal cations in the alkaline water, atomizing the metal, decomposing the water using the atomized metal, generating hydrogen from the decomposed water, generating metal oxides through an oxidation reaction of the metal with oxygen generated from the decomposed water, and generating hydrogen water in a state where the generated hydrogen is encapsulated in fan bubble bubbles that are less likely to explode and can remain in the water.

7. The alkaline water in claim 6 is water prepared by dissolving alkali metals and alkaline earth metals from Groups 1 and 2 of the periodic table. It can also be natural well water, spring water, seawater, or hot spring water in which alkali metals or alkaline earth metals are dissolved. It can also be alkaline water to which other substances have been added.

8. The present invention provides a method for generating heat by causing a hydration reaction between the metal oxide and water, and a method for generating hot water by using the generated heat.

9. Proton H ＋ The atomic hydrogen H generated by the fine bubble generator made of the material of claim 2 and by carrying out claim 1 is converted into H ＋ This method produces hydrogen water by reducing hydrogen and enclosing the produced hydrogen in fan-bubble bubbles that are less likely to burst and can remain in the water.

10. The proton H of claim 9 ＋ Water that is rich in these acids is water that has been adjusted by dissolving various organic and inorganic acids. It can also be natural well water, spring water, hot spring water, or seawater that contains dissolved organic and inorganic acids. Acetic acid, lactic acid, citric acid, L-ascorbic acid (vitamin C), and squeezed vegetable or fruit juices are also acceptable.

11. A hydrogen generating material and bath additive are produced by using a fine bubble generator made of the material of claim 2 and adding one or more of the organic acids, inorganic acids, alkali metals, and alkaline earth metals used to implement claim 1.

12. By using a fine bubble generator made of the material of claim 2 and carrying out claim 1, the following methods are available for producing water that has been eliminated by the reaction in which active oxygen is reduced to water by the atomic hydrogen generated, water containing atomic hydrogen, hydrogen water in which two atomic hydrogen atoms combine, and dissolved hydrogen water that contains hydrogen generated by atomized metals and encapsulated in fine bubbles.These methods also produce reduced water, atomic hydrogen water, and dissolved hydrogen water that can be consumed or have the function of eliminating active oxygen through its reducing power and suppressing the oxidation of substances.

13. This method uses a fine bubble generator made of the material of claim 2 to burn hydrogen or hydrogen water produced by the methods of claims 1, 6, and 9 as fuel to obtain thermal energy, or to operate a fuel cell to generate electricity to obtain electrical energy.

14. Claims 5, 6, 8, 9 and 11 relate to a method for directly utilizing the generated heat or hot water as thermal energy, and a method for converting thermal energy into electrical energy using a thermoelectric element.

15. An energy production system comprising a hydrogen production unit equipped with an apparatus for producing hydrogen or hydrogen water as described in claim 1 or claim 5 and a heat storage device for recovering the heat generated, a hydrogen purification unit for purifying hydrogen from the produced hydrogen water, a fuel storage unit for storing the produced hydrogen gas or hydrogen water, a fuel cell power generation unit using hydrogen gas or hydrogen water, a thermoelectric device unit for converting the stored heat into electrical energy, a power storage unit for storing the generated electricity, a solar power generation unit for supplying electricity to operate the hydrogen production apparatus, etc., and an energy management unit for adjusting the electricity generated in each unit.

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