JPH10212101A - Catalyst for producing hydrogen and oxygen and production of the same by thermal decomposition of water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower the reaction temp. and to miniaturize the equipment by charging a mineral consisting essentially of silicon dioxide and another one consisting essentially of titanium oxide to a furnace vessel, reducing the pressure, injecting a pure water before or after reducing the pressure and simultaneously increasing stepwise the temp. of the inside of the furnace vessel and after reaching a specific final objective temp., keeping at the temp. under heating and additionally injecting the pure water. SOLUTION: The furnace vessel having a heat source capable of controlling the temp. and capable of rotating, vibrating and stirring is used. The quantity of the pure water to be initially injected is controlled to equal to or above that of the mineral. The starting temp. of the furnace vessel is setted to 100-200 deg.C, the final objective temp. is setted to 350-700 deg.C and the temp is increased so that the difference of the temp. at >=10min intervals from the starting temp is at least <=100 deg.C. After reaching the final objective temp., the temp. of the furnace vessel is maintained under heating so as not to be lowered to <=350 deg.C and the pure water is additionally injected so that the quantity of the pure water present in the furnace vessel is equal to or above that of the mineral.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing hydrogen and oxygen by pyrolysis of water.

[0002]

2. Description of the Related Art In general, hydrogen and oxygen are generally produced by a method in which water and hydrogen are produced by electrolysis of water described in high school textbooks or the like. A steam reforming method obtained by reacting with benzene is generally well known. It is known that water decomposes into hydrogen and oxygen in the presence of a catalyst such as iron at a high temperature of 1000 ° C. or higher. However, the electrolysis method has hardly spread in countries where electricity rates are high like Japan, and the steam reforming method, which can select a heat source such as heavy oil that is more efficient than electric energy, has spread. You can say. But,
In the steam reforming method, the reaction temperature is high as described above,
There is a problem with emission of carbon dioxide which causes global warming, and it can be said that it is an electrolysis method, but it has a disadvantage that equipment becomes large-scale. In addition to these, in Japanese Patent Application No. 165765 filed by Asahi Kasei Kogyo which the inventor of the present invention pays attention, in the claims, "contacting fine powder of silicon having an average particle diameter of 2 μm or less with water. The method of producing hydrogen is characterized by the fact that the reaction temperature is only several tens of degrees Celsius higher than room temperature, and that silicon is merely micronized. It is clear that this is separate from For example, the inventor's invention is based on the fact that, as described later, a natural silicon oxide substance that takes a noble potential oxidation-reduction potential (positive electrode potential) like a noble metal such as silver or the like such as iron or zinc. This is a major difference in that a catalyst whose base potential has been reduced to the oxidation-reduction potential (negative electrode potential) of a base potential, such as a base metal, is manufactured. Further, as described in Examples, the hydrogen generation rate by the method of the present inventor is similar to the hydrogen production method of Asahi Kasei Kogyo even if it is as large as practical, but the fine powder of silicon is used. It is noteworthy that the contact with water produces a significant amount of hydrogen. However, in the above-mentioned invention of Asahi Kasei Kogyo, the method of bringing silicon into contact with water is stirring or shaking, and the ultrafine powdering of silicon powder improves the rate of hydrogen generation. The inventor of the present invention believes that this is exactly the case. In addition, it is stated that the water used for hydrogen production is not necessarily pure water, but may be tap water or industrial water. However, according to the inventor's experience, this is true. However, a silicon oxide or titanium oxide catalyst for producing hydrogen and oxygen, which decomposes water with high efficiency, will be described later, but it is certain that the production is not easy unless pure water is used.

[0003]

The method for producing hydrogen and oxygen according to the present invention aims at lowering the reaction temperature and miniaturizing the production equipment as compared with the conventionally well-known steam reforming method. .

[0004]

In order to solve the above-mentioned problems, a method for producing a catalyst for producing hydrogen and oxygen includes a method for producing a pulverized mineral mainly composed of silicon dioxide such as natural zeolite and silica, and a rutile ore. Pulverized mineral containing titanium dioxide as a main component such as is previously charged into a rotatable or vibrating or stirrable furnace vessel having a temperature controllable heat source,
While the furnace vessel (hereinafter referred to as "furnace vessel") is rotated or vibrated or the inside of the furnace vessel is stirred, the inside of the furnace vessel is evacuated to a vacuum state, and before and after the evacuation, the weight is equal to or greater than that of the mineral. And the starting temperature in the furnace vessel is set to 100 ° C. to 200 ° C. and the final target temperature in the furnace vessel to about 350 ° C. to 700 ° C., and the temperature in the furnace vessel is reduced from the starting temperature. The temperature inside the furnace vessel is gradually increased so that the temperature inside the furnace vessel is raised at a temperature difference of at least about 100 ° C. or less at a time interval of about 10 minutes or more, and after reaching the final target temperature, the temperature inside the furnace vessel is 350 ° C. or less. By additionally injecting such that the amount of pure water present in the furnace vessel is equal to or greater than the weight of the mineral, while heating and holding so as not to be deoxidized, deoxidation from oxides and hydrogen from water due to the deoxidation are performed. And oxygen Oxygen concentration increase due to the decomposition of the gas occurs continuously, and at or around the time when the oxygen concentration in the furnace container reaches an equilibrium state, the discharge of hydrogen, oxygen, and water vapor by evacuating the furnace container to a vacuum state is performed. By repeating the process, the oxidation-reduction potential of the catalyst is sufficiently reduced, and then the reaction rate of the decomposition reaction of pure water into hydrogen and oxygen is improved. The method for producing hydrogen and oxygen is provided in a furnace container having a heat source capable of controlling the temperature, which can be rotated, vibrated, or stirred.
The catalyst described above is charged in advance and brought into contact with pure water, and in order to continuously and efficiently decompose hydrogen and oxygen from pure water to produce the pure water, the amount of pure water present in the furnace vessel is about the same as the catalyst weight. Injecting at any time so that the above can be maintained,
While the furnace vessel (hereinafter referred to as "furnace vessel") is rotated or vibrated or stirred in the furnace vessel, the inside of the furnace vessel is evacuated to a vacuum state, and before and after the evacuation, the starting temperature in the furnace vessel is reduced. 100 ° C. to 200 ° C. and a final target temperature in the furnace vessel set at about 350 ° C. to 700 ° C., and a temperature in the furnace vessel at a temperature interval of at least about 100 ° C. or less at a time interval of about 10 minutes or more from the starting temperature. In order to raise the temperature by the difference, the temperature inside the furnace vessel is increased stepwise, and after reaching the final target temperature, while heating and holding the temperature inside the furnace vessel so as not to be 350 ° C. or less, deoxidation from oxides and Oxygen concentration rises due to the decomposition of water into hydrogen and oxygen by the deoxidation, and the decomposition reaction rate of pure water to hydrogen and oxygen is improved before and after reaching the equilibrium state of the oxygen concentration in the furnace vessel. To make The serial furnace vessel and repeating the recovery of hydrogen and oxygen and water vapor by drawing a vacuum to a vacuum state. The weight of the catalyst is about 1% by weight or more based on the volume of the furnace vessel.
If it is 0 liters, it is sufficient that the amount is 100 g or more. However, in consideration of the deterioration of the catalyst, in order to enable continuous operation for a long period of time, it is preferable that the weight of the catalyst is large, and the volume ratio is about 10 wt% It is desirable that the content be 50% by weight.

The measured value of the oxidation-reduction potential (also referred to as electrode potential) of the catalyst using the mineral as a catalyst according to claim 1, wherein the decomposition reaction rate of hydrogen from pure water to hydrogen and oxygen is improved to a practical extent. The lowest one is -700 m as will be described later in Examples.
V, and the measuring method is as follows. At room temperature of 25 ° C. under the open air, the catalyst powder is sealed in a thin glass tube provided with a bottom glass filter, and the glass tube is immersed in a container containing pure water, and the powder is dried. The platinum electrode inserted inside is a saturated calomel electrode (H
g · Hg 2 Cl 2 / KCl saturated) as a reference electrode (that is, the platinum electrode is liquid junction with the reference electrode via a salt bridge formed by dissolving saturated potassium chloride in agar), The electrode potential is defined as a read value of a potentiometer (electrometer) having a high internal resistance connected between the two electrodes. The specific measurement method is described in, for example, "Electrochemical Measurement Method (1)" by Akira Fujishima et al., Published by Gihodo Shuppan. Since the color of this mineral is dark dark gray, it is considered that this mineral is a mixture of silicon dioxide and silicon monoxide (hereinafter, referred to as “silica oxide”). Incidentally, the mineral before use is slightly different depending on the kind of the mineral, but the electrode potential is about + several hundred mV, and the color of the mineral is white, light gray, light beige or the like. As described above, by heating and baking while injecting pure water into a furnace container containing the catalyst, the greater the number of evacuations of hydrogen and oxygen decomposed from the pure water, the lower the electrode potential of the catalyst. be able to. The fact that the lower the electrode potential is, the higher the decomposition reaction rate of pure water to hydrogen and oxygen with the catalyst is, without doubt, from the results of Examples described later. It is clear that the compound has a function as a catalyst for accelerating the decomposition reaction into methane. In the method for producing hydrogen and oxygen for decomposing pure water according to claim 2, the reason for bringing the catalyst according to claim 1 into contact with pure water and increasing the temperature inside the furnace vessel stepwise is as follows.
In order to prolong the service life of the catalyst, it is desirable that the temperature rise in the furnace vessel be as small as possible. In claim 2, even when the temperature inside the furnace vessel is rapidly increased to about 350 ° C., it goes without saying that pure water is decomposed into hydrogen and oxygen. However, the adverse effect is empirically found that as the temperature in the furnace vessel containing the catalyst rises steeply,
The specific surface area of the catalyst powder is reduced. That is, the catalyst often changes from a powdery state to a massive state. In such a case, the pure water causes a reduction in the rate of the decomposition reaction into hydrogen and oxygen, which is inconvenient. The same can be said for the catalyst production method. The starting temperature in claim 2 is set to be as low as about 100 ° C., and the final target temperature is set to about 5 ° C.
From about 00 ° C. to about 700 ° C., from about 10 minutes
The temperature inside the furnace vessel is gradually increased so as to gradually increase the temperature by about 50 ° C. at a time interval of 20 minutes, and after reaching the final target temperature, the temperature inside the furnace vessel becomes 350 ° C.
Deoxidation from oxides or its deoxidation by injecting as necessary so that the pure water previously injected to the same weight or more as the mineral weight remains in the furnace vessel while heating and holding so as not to be below ℃. Oxygen concentration rises due to decomposition of hydrogen and oxygen from water by water, and when reaching an equilibrium state of oxygen concentration in the furnace vessel, hydrogen, oxygen, and water vapor by evacuation of the furnace vessel to a vacuum state It is desirable to take out the powder of the dark dark gray mineral obtained by repeating the discharge, and if the particle size of the powder is large, make it as small as possible such as finely pulverizing it to at least several tens of microns or less. Further, when the reduction reaction proceeds excessively to generate and mix agglomerated metal silica in the powder, the specific surface area of the metal silica that contributes to the reduction reaction of pure water acting as a catalyst is silicon dioxide and silicon monoxide. Since it is smaller than the silica oxide, it is preferable to remove it. Further, in claim 1 and claim 2, "the deoxidation from the oxide and the increase in the oxygen concentration due to the decomposition of water into hydrogen and oxygen by the deoxidation occur, and the oxygen concentration in the furnace vessel reaches the equilibrium state. At or before or after, in order to improve the decomposition reaction rate of pure water into hydrogen and oxygen, the recovery of hydrogen, oxygen and water vapor by evacuating the furnace vessel to a vacuum state is repeated. " There is a judgment that it is not energy-efficient to operate the vacuum pump constantly to evacuate the inside of the pump, so it is not energy-efficient to perform the reaction according to the catalyst performance related to the decomposition reaction rate of pure water to hydrogen and oxygen. The most advantageous operation mode of the vacuum pump may be selected.
Further, in claim 1 and 2, regarding the production of the catalyst and the decomposition of pure water into hydrogen and oxygen by the catalyst, when tap water is used instead of pure water, a predetermined performance with a low electrode potential is satisfied. Although production of the catalyst was empirically difficult, there was no problem in producing hydrogen and oxygen from the catalyst. However, the use of tap water or the like is not always convenient in terms of maintenance and management of the equipment because the problem of corrosion of the equipment is more likely to occur than with pure water. Therefore, the water used as the raw material for producing hydrogen and oxygen according to claim 2 is designated as pure water. In the method of the present invention, a mixed gas of hydrogen, oxygen, and steam is obtained by decomposing pure water,
It is necessary to separate high-purity hydrogen gas from this mixed gas, but the method is not described in detail here, and is given to relevant literature such as "Hydrogen Storage Alloy Data Book" by Yasuaki Osado published by Yono Shobo. However, there are known a separation and recovery method using a hydrogen storage alloy that selectively stores only hydrogen, and an adsorption method (PSA) that removes impurities such as oxygen by utilizing a difference in adsorption efficiency between zeolite and activated carbon.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a system diagram of a test apparatus for thermally decomposing pure water into hydrogen and oxygen according to the present invention. Tables 1 and 2 show the first example of the operation test data for producing the catalysts for producing hydrogen and oxygen by pyrolysis of water of the present invention, respectively, using silica oxides of natural zeolite and silica oxide as raw materials. And a second embodiment. As described below, as the pure water reduction reaction proceeds, the produced catalyst is estimated to be a mixture of silicon dioxide and silicon monoxide in which the blending ratio of silicon monoxide has increased. The oxidation-reduction reaction of silica oxide and the reduction reaction of pure water with respect to the produced catalyst are considered to be as follows. Reduction reaction of catalyst: SiO2 = SiO + O Reduction reaction of pure water: H2O + O = H2 + O2 Oxidation reaction of catalyst: SiO + 1 / 2O2 = SiO2 Table 3 shows that titanium oxide is used as a raw material, and hydrogen is generated by thermal decomposition of water of the present invention. It is a 3rd Example of the operation test data which produced the catalyst for oxygen production. As described below, as the reduction reaction of pure water progresses, it is estimated that the produced catalyst is a mixture of titanium dioxide and titanium monoxide in which the mixing ratio of titanium monoxide has increased. The oxidation-reduction reaction of titanium oxide and the reduction reaction of pure water with respect to the produced catalyst are considered to be as follows. Reduction reaction of catalyst: TiO2 = TiO + O Reduction reaction of pure water: H2O + O = H2 + O2 Oxidation reaction of catalyst: TiO + 1 / 2O2 = TiO2 In Examples of Tables 1 to 3, as the elapsed time elapses,
It can be seen that the reaction rate for thermally decomposing pure water into hydrogen and oxygen is improved by improving the performance of the catalyst. Therefore, in the embodiment of the operation test data relating to the method for producing hydrogen and oxygen obtained by thermal decomposition from pure water, it is sufficient to use a catalyst having a sufficiently long elapsed time, and the same operation test data can be obtained. I have. In Examples of Tables 1 to 3, the inside of a stainless steel furnace vessel (hereinafter, referred to as a "furnace vessel") was previously set to 0.1 mm.
After evacuating to an absolute pressure less than atmospheric pressure, about 2 liters of water are injected, and the inlet and outlet valves are closed, except for the outlet valve which is 1.
A pressure regulating valve that opens at 5 atmospheres or more is provided. After that, while heating the furnace vessel, online measurement of the oxygen concentration of the generated oxygen was carried out, so high-precision data was obtained, but for the hydrogen concentration, batch measurement using a gas tech hydrogen gas detector tube Therefore, the on-line measurement during the experiment cannot be performed, and the data is collected immediately before the end of the test. The accuracy of the measurement data is not so good as compared with the on-line measurement data of the oxygen concentration. At the time of heating the furnace vessel, initially, most of the water is in the furnace vessel and only a small amount of air is present. Is seen to rise rapidly. The hydrogen concentration (vol%) is about 1 to 2 times the value of the oxygen concentration (vol%) in Table 1,
Further, the water vapor concentration is substantially equal to a value obtained by subtracting the sum (volume%) of the oxygen concentration and the hydrogen concentration from 100%. Hereinafter, Tables 1 to 3 show test results obtained by using the silica oxide and titanium oxide of claim 1 as catalysts and decomposing water into hydrogen and oxygen under the following test conditions. However, the oxygen concentration and the hydrogen concentration were measured at room temperature. The table on the separate sheet shows that the rate of increase in the oxygen concentration in the furnace vessel increases as the elapsed time increases. For example, in the case of Table 1,
At 78 minutes, the inside of the furnace vessel was evacuated,
Oxygen concentration is increased 80 minutes after pure water is injected. Similarly, the same applies from 800 minutes to 802 minutes, but the greater the elapsed time, the higher the rate of increase in the oxygen concentration. Furthermore, in the case of Table 2, at 78 minutes, the inside of the furnace vessel was evacuated, and simultaneously,
At 0 minutes, the oxygen concentration is increasing. Similarly 150
The same applies to the period from 0 minute to 1506 minutes, but the longer the elapsed time, the higher the oxygen concentration increase rate. Table 3
In the case of (1), the inside of the furnace vessel was evacuated at 78 minutes and pure water was injected at the same time, and the oxygen concentration increased at 80 minutes. Similarly, the same applies from 1000 minutes to 1002 minutes, but the longer the elapsed time, the higher the rate of increase in the oxygen concentration. As shown in Table 1 of the attached sheet, among the catalysts of the same element, those having a low electrode potential have a high decomposition efficiency of pure water to hydrogen and oxygen, and the hydrogen of pure water in the catalyst after the reaction is completed. The decomposition efficiency to oxygen is almost equal to the operation test data immediately before the end of the reaction (elapsed time 8
The decomposition reaction from 00 minutes to 802 minutes is shown. ), The oxygen and hydrogen generation rates in this case are determined by Boyle-Charles' law as follows: oxygen: 0.3 Nm 3 / h, hydrogen:
It is calculated to be 0.45 Nm3 / h. The amount of power used at this time is about 2 kWh. Therefore, the production efficiency of hydrogen, in the case of the conventional water electrolysis method and the steam reforming method,
It is said that about 6 kWh of electric power is required per 1 Nm3 of hydrogen, but it is considered that it is not inferior to these.

The test conditions in the following Tables 1 to 3 are listed at the end of the page of the specification.

[Table 1] ~

This corresponds to the example of Table 3. (Test conditions in Table 1) Stainless steel furnace container volume: 13 liters Storage tank volume: 26 liters Extraction pipe volume: 3 liters Catalyst type: natural zeolite Catalyst weight: 500 g Electrode potential of the catalyst before the start of the reaction (actual value): +200 mV Electrode potential of catalyst after completion of reaction (actual measurement value): -700 mV (test conditions in Table 2) Stainless steel furnace container volume: 13 liter Storage tank volume: 26 liter Extraction pipe volume: 3 liter Catalyst type: quartz Catalyst weight : 500 g Electrode potential of catalyst before start of reaction (actual value): +200 mV Electrode potential of catalyst after reaction (actual value): -100 mV (Test conditions in Table 3) Stainless steel furnace container volume: 13 liter Storage tank volume: 26 liters Extraction pipe volume: 3 liters Catalyst type: rutile ore Catalyst weight: 500 g Catalyst before the start of reaction Electrode potential (actual value): +400 mV Electrode potential of catalyst after completion of reaction (actual value): +50 mV

[0008]

At present, it is well known that hydrogen is used in large quantities in a wide range of industrial fields such as the chemical industry, semiconductor device manufacturing, metallurgy and food processing. As described above, according to the present invention, as described above, the reaction temperature is lower and the equipment can be reduced in size as compared with a conventionally well-known steam reforming method or the like. Also, unlike the steam reforming method, the only raw material is pure water.In recent years, carbon dioxide emissions have become extremely low as carbon dioxide emissions are being regulated worldwide due to global warming. Are also considered important advantages. Above all, the reaction temperature at which pure water decomposes into hydrogen and oxygen is as low as about 350 ° C, so waste heat from turbines in thermal power plants and nuclear power plants and waste heat from incinerators in municipal incineration plants Hydrogen production is also possible. For this reason, it is expected that the production cost of hydrogen can be significantly reduced. In the past, hydrogen gas could not be produced unless it was a large-scale business establishment.However, the possibility of producing hydrogen gas at a small-scale business establishment has been created.In the future, gasoline and light oil It can also contribute to the spread of hydrogen vehicles, which have a lower environmental impact than vehicles using hydrogen as fuel.

[0009]

[Brief description of the drawings]

FIG. 1 is a system diagram of an apparatus for producing hydrogen and oxygen obtained by thermally decomposing pure water according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Furnace container 2 Electric heater 3 Mixed gas storage container 4 Pure water storage container 5 Vacuum pump 6 Thermocouple temperature control device 7 Oxygen meter 8 Circulation pump (for injection and return of catalyst and water) 9 Inlet valve 10 Outlet valve 11 Isolation valve

[0010]

Table 1 Elapsed time (minutes) | Temperature (° C) ------------------------------------------- | Injection volume (liter) | Pressure (atmospheric pressure) | Oxygen concentration (%) | Hydrogen concentration (%) -------------------------------------- −−−−−−−−− 0 | 15 | 2 | 0.1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−− 13 | 100 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −26− 150 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 39 | 200 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 52 | 250 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−−−−−−− 65 | 300 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−− 78 | 350 | 0.3 | 0.1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−− 80 | 350 | 0 | 0.5 | 2 | −−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−− Hereinafter, the test data of the elapsed time in the middle is omitted. .....................-------------------------------------------------------------------------------------------------------- −−−−−−−−−−− 800 | 350 | 0.3 | 0.2 | 0 | −−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−− 802 | 350 | 0 | 1.6 | 21 | Approx. 30 −−−−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−−

[0011]

Table 2 Elapsed time (minutes) | Temperature (° C)------------------------------ | Injection volume (liter) | Pressure (atmospheric pressure) | Oxygen concentration (%) | Hydrogen concentration (%) -------------------------------------- −−−−−−−−− 0 | 15 | 2 | 0.1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−− 13 | 100 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −26− 150 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 39 | 200 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 52 | 250 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−−−−−−− 65 | 300 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−− 78 | 350 | 0.3 | 0.1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−− 80 | 350 | 0 | 0.5 | 1 | −−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−− Hereinafter, the test data of the elapsed time in the middle is omitted. .....................-------------------------------------------------------------------------------------------------------- −−−−−−−−−− 1500 | 350 | 0.3 | 0.2 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−− 1506 | 350 | 0 | 0.9 | 18 | Approx. 20 --------------------------------------------------------- −−−−−−−−−−−−

[0012]

Table 3 Elapsed time (minutes) | Temperature (° C) ------------------------------------------- | Injection volume (liter) | Pressure (atmospheric pressure) | Oxygen concentration (%) | Hydrogen concentration (%) -------------------------------------- −−−−−−−−− 0 | 15 | 2 | 0.1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−− 13 | 100 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−−−−−− −26− 150 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 39 | 200 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− 52 | 250 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−−−−−−− 65 | 300 | 0 | 1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−− 78 | 350 | 0.3 | 0.1 | 0 | −−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−− 80 | 350 | 0 | 0.5 | 1 | −−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−− Hereinafter, the test data of the elapsed time in the middle is omitted. .....................-------------------------------------------------------------------------------------------------------- −−−−−−−−−−− 1000 | 350 | 0.3 | 0.2 | 0 | −−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−− 1002 | 350 | 0 | 0.8 | 14 | about 20 −−−−−−−−−−−−−−−−−−−−−−−−−−− −−−−−−−−−−−−

Claims (2)

[Claims] 1. A crushed mineral mainly composed of silicon dioxide such as natural zeolite and silica stone, and a crushed mineral mainly composed of titanium dioxide such as rutile ore (hereinafter, both crushed minerals are referred to as "mineral"). Minerals) are previously charged into a rotatable, vibrating, or stirrable furnace vessel having a temperature controllable heat source, and the furnace vessel (hereinafter, referred to as a "furnace vessel") is rotated, vibrated, or stirred inside the furnace vessel. While the inside of the furnace container was evacuated to a vacuum state, before and after the evacuation, pure water having a weight equal to or more than that of the mineral was injected, and the starting temperature in the furnace container was set to 100 ° C. to 200 ° C.
And a final target temperature in the furnace vessel of about 350 ° C to 700 ° C.
The temperature inside the furnace vessel is increased stepwise so that the temperature inside the furnace vessel is raised from the starting temperature by a temperature difference of at least about 100 ° C. at a time interval of about 10 minutes or more, and the final temperature is increased. After reaching the target temperature, the temperature inside the furnace
Deoxidation from oxides (oxygen desorption) by additionally injecting so that the amount of pure water present in the furnace vessel is equal to or greater than the weight of the mineral while heating and maintaining the temperature not to be below 0 ° C. The same shall apply hereinafter) and the deoxygenation of water to decompose water into hydrogen and oxygen to continuously increase the oxygen concentration, and at or before and after the oxygen concentration in the furnace reaches an equilibrium state, By reducing the oxidation-reduction potential of the mineral by repeatedly discharging hydrogen, oxygen, and water vapor by evacuating the inside to a vacuum state, the reaction rate for the decomposition reaction of pure water into hydrogen and oxygen is improved. A method for producing a catalyst for producing hydrogen and oxygen. 2. The catalyst according to claim 1 is previously charged into a rotatable, vibrating or agitating furnace vessel having a heat source whose temperature can be controlled and brought into contact with pure water, so that hydrogen and oxygen can be continuously and efficiently obtained. In order to decompose the catalyst from pure water and to produce the same, the amount of pure water present in the furnace vessel can be maintained at a level equivalent to or greater than the weight of the catalyst, and at any time, the furnace vessel (hereinafter, referred to as “furnace vessel”). ) Is evacuated to a vacuum state while rotating or vibrating or stirring the inside of the furnace container, and before and after the evacuation, the starting temperature in the furnace container is set to 100 ° C. to 200 ° C. A final target temperature is set at about 350 ° C. to 700 ° C., and the temperature in the furnace vessel is raised from the starting temperature by a temperature difference of at least about 100 ° C. at time intervals of about 10 minutes or more,
After the temperature inside the furnace vessel is increased stepwise, and after reaching the final target temperature, deoxidation from oxides and water from the water by the deoxidation are performed while heating and holding the temperature inside the furnace vessel so as not to be 350 ° C. or lower. Oxygen concentration increase due to decomposition into hydrogen and oxygen occurs, and at or before and after reaching an equilibrium state of oxygen concentration in the furnace vessel, to improve the rate of decomposition reaction from pure water to hydrogen and oxygen in the furnace vessel, A method for producing hydrogen and oxygen, comprising repeating the recovery of hydrogen, oxygen and water vapor by evacuating to a vacuum state.