JP5103166B2 - Hydrogen generator and hydrogen generation method - Google Patents

Description

  The present invention relates to a hydrogen generation apparatus and a hydrogen generation method for generating hydrogen gas by supplying a reaction liquid such as moisture to a hydrogen generating agent, and is particularly useful as a technique for supplying hydrogen to a fuel cell.

  Conventionally, as a hydrogen generating agent for supplying hydrogen to generate hydrogen gas, a main component is a metal such as iron or aluminum, or a main component is a metal hydride such as magnesium hydride or calcium hydride. Is known (see, for example, Patent Document 1). In particular, when a hydrogen generator containing calcium hydride as a main component is used, the reaction rate with moisture is steep, and therefore, when moisture is supplied in liquid (water), hydrogen gas is explosively generated at an early stage. was there.

  For example, when 1 g of calcium hydride and water are completely reacted, 1.16 L (theoretical amount) of hydrogen gas is generated, 0.85 g (theoretical amount) of water is required, and 1 L / h of water is generated. In the case of speed, it is necessary to supply water at about 1 mL / h (0.28 μL / second). However, even if it is attempted to supply water at such a small flow rate using a syringe pump, the flow rate becomes uneven because the supply amount cannot be precisely controlled, and the influence of the size of the droplets is also affected. The amount of supply increases, especially when water is first supplied. This reacted rapidly with calcium hydride, and hydrogen gas was generated explosively at an early stage.

  Thus, Patent Documents 2 to 3 disclose a hydrogen generation method for supplying generated water vapor to calcium hydride through a hydrophobic porous body for the purpose of appropriately controlling the reaction rate between calcium hydride and moisture. Has been. At this time, the amount of water vapor generated and the amount supplied are controlled by the area of the hydrophobic porous body, the porosity, etc., but the water vapor is itself generated by natural evaporation.

  However, in the method of supplying water vapor, although the reaction with calcium hydride can be mild, it is difficult to change the amount of water vapor generated, or to change or stop the supply amount. I could not say it. Further, even when the amount of water vapor generated is changed by heating or the like, there is a problem that the response of the amount of hydrogen generated is poor and the required energy increases.

JP 2003-313001 A JP 2003-313001 A JP 2004-269323 A

  Therefore, even when a highly reactive hydrogen generator is used, the object of the present invention is to precisely control the reaction with the reaction solution from the start of the reaction, and to easily change or stop the supply amount of the reaction solution. An object of the present invention is to provide a hydrogen generation apparatus and a hydrogen generation method.

  As a result of intensive research on the method of supplying a small amount of water, the inventors of the present invention intermittently discharge the reaction solution into the reaction vessel so that the discharge amount of the reaction solution for one time at least in the initial stage is 10 μL or less. Thus, the inventors have found that the above object can be achieved and have completed the present invention.

  That is, the hydrogen generator of the present invention includes a liquid container that contains a reaction liquid, a reaction container that contains a hydrogen generating agent, and a reaction liquid supply mechanism that supplies the reaction liquid in the liquid container to the reaction container. The reaction liquid supply mechanism intermittently discharges the reaction liquid into the reaction vessel so that the discharge amount of the reaction liquid for one batch at least in the initial stage is 10 μL or less. And

  According to the hydrogen generating apparatus of the present invention, since the reaction liquid supply mechanism that intermittently discharges the reaction liquid with a discharge amount of 10 μL or less at one time into the reaction vessel is provided, Compared with the case where the liquid can be discharged and supplied continuously at a constant speed, the amount of the reaction liquid supplied first does not become excessive, and even when a highly reactive hydrogen generator is used, Explosive hydrogen generation hardly occurs. Further, by changing the interval of intermittent discharge, the supply amount of the reaction liquid can be easily changed, and it can be stopped. As a result, even when a highly reactive hydrogen generator is used, the reaction with the reaction liquid can be precisely controlled from the start of the reaction, and the supply amount of the reaction liquid can be easily changed or stopped.

  The present invention is particularly effective for a highly reactive hydrogen generator, and the highly reactive hydrogen generator is one having a reactivity with water at room temperature that is higher than that of magnesium hydride. When such a highly reactive hydrogen generating agent is used, the reaction is quickly performed each time the reaction liquid is discharged, so that the responsiveness of the hydrogen generation amount is good with respect to the change in the supply amount of the reaction liquid. It will be a thing.

  In the present invention, the reaction liquid supply mechanism includes a valve mechanism for intermittently discharging the reaction liquid, a valve control unit for controlling opening and closing of the valve mechanism, and a pressure mechanism for pressurizing a primary side of the valve mechanism. It is preferable that the valve control unit intermittently controls the opening and closing of the valve mechanism so that the initial opening time is 60 milliseconds or less.

  According to this configuration, the valve control unit intermittently controls the opening and closing of the valve mechanism with a short opening time, so that a minute amount of reaction liquid can be intermittently discharged by the pressurizing mechanism that pressurizes the primary side. it can. Further, according to this configuration, the supply amount of the reaction liquid can be easily changed or stopped by changing the opening / closing timing of the valve mechanism.

  Moreover, it is preferable that the liquid container is formed of a deformable member, and the pressurizing mechanism includes a biasing unit that biases the deformable member. According to this configuration, when the valve mechanism is opened, the liquid storage container is deformed by the elastic restoring force of the biasing means, and the reaction liquid in the container can be discharged. Thus, a discharge force can be applied.

  On the other hand, the hydrogen generation method of the present invention is characterized in that the reaction solution is intermittently supplied to the hydrogen generating agent so that the discharge amount of the reaction solution at least once in the initial stage is 10 μL or less.

  According to the hydrogen generation method of the present invention, an extremely small amount of reaction liquid with a discharge amount of 10 μL or less is intermittently supplied into the reaction vessel, so that an extremely small amount of reaction liquid is reliably discharged and supplied. Compared with the case of continuous supply at a constant rate, the amount of the reaction solution supplied at the beginning does not become excessive, and even when a highly reactive hydrogen generator is used, explosive hydrogen generation occurs. Hard to get up. Further, by changing the interval of intermittent discharge, the supply amount of the reaction liquid can be easily changed, and it can be stopped. As a result, even when a highly reactive hydrogen generator is used, the reaction with the reaction liquid can be precisely controlled from the start of the reaction, and the supply amount of the reaction liquid can be easily changed or stopped.

  In the above, it is preferable to supply the reaction liquid by intermittently opening and closing the valve mechanism so that at least the initial opening time is within 60 milliseconds. According to this configuration, the supply amount of the reaction liquid can be easily changed or stopped by changing the opening / closing timing of the valve mechanism.

  Moreover, it is preferable that the reaction liquid discharged to the said hydrogen generating agent is discharged in mist form. By discharging the mist-like reaction liquid to the hydrogen generating agent, the reaction between the hydrogen generating agent and the reaction liquid can be performed more reliably without excessive supply of the reaction liquid locally. While controlling mildly, the responsiveness of the hydrogen generation amount can be further improved.

  Hereinafter, preferred embodiments of a hydrogen generation apparatus and a hydrogen generation method according to the present invention will be described with reference to the drawings. FIG. 1 is a conceptual diagram showing a configuration of a hydrogen generator and a fuel cell system including the hydrogen generator.

<Hydrogen generator>
The hydrogen generator A of the present invention includes a liquid storage container 1, a reaction container 2, and a reaction liquid supply mechanism. The reaction liquid supply mechanism preferably includes a valve mechanism 3 for intermittently discharging the reaction liquid, The valve control unit 8 that controls the opening and closing of the valve mechanism 3 and the pressurizing mechanism that pressurizes the primary side of the valve mechanism 3 are provided.

  The pressure of the reaction liquid in the liquid container 1 generated by the pressurizing mechanism is preferably 2 to 100 KPa, more preferably 10 to 50 KPa, from the viewpoint of suitably discharging the reaction liquid.

  Water as a reaction liquid is stored in the liquid storage container 1. This water has a function of generating hydrogen gas by reacting with the hydrogen generator. In addition to water, a solution such as acid or alkali may be used. The liquid container 1 is made of an elastic member (silicone rubber or the like), has an elastic restoring force in the shrinking direction, and is formed in a so-called balloon shape. For this reason, the material which comprises the liquid container 1 acts as a pressurization mechanism which pressurizes the primary side of the valve mechanism 3. The amount of water injected into the liquid container 1 is determined according to the amount of the hydrogen generating agent, but is about 1 to 10 cc when used for a portable device.

  A hydrogen generating agent is accommodated in the reaction vessel 2. The hydrogen generating agent reacts with a reaction liquid such as water to generate hydrogen gas, and the present invention is particularly effective for a highly reactive hydrogen generating agent. Examples of such highly reactive hydrogen generators include calcium hydride, lithium hydride, potassium hydride, sodium borohydride, potassium borohydride, lithium aluminum hydride, sodium aluminum hydride, or magnesium hydride. The thing to contain is mentioned. All of these compounds are known to react rapidly or explosively with water to generate hydrogen gas, and all show reactivity with water higher than magnesium hydride.

  The hydrogen generating agent may contain other components such as a hydrogen generating agent other than the above compounds, a catalyst, an aggregation inhibitor, a binder, and a filler. The hydrogen generator may be in the form of a powder, granulated or tableted. The reaction solution may be directly discharged to the hydrogen generating agent, but the reaction solution may be supplied to the hydrogen generating agent through a water-absorbing material.

  Between the liquid storage container 1 and the reaction container 2, a valve mechanism 3 for intermittently discharging the reaction liquid in the liquid storage container 1 is provided. The valve mechanism 3 controls the opening and closing of the flow path, and the water in the liquid container 1 is discharged into the reaction container 2 by opening the flow path. At this time, as in the present invention, when the opening time is sufficiently short and the pressure on the primary side of the valve mechanism 3 is sufficiently high, the reaction solution can be discharged intermittently. That is, if the pressure on the primary side is sufficiently high, intermittent discharge is performed even when the pressure is applied to the reaction liquid in a pulsed manner by opening and closing the valve mechanism 3 and the liquid is accumulated at the tip of the pipe. Can do.

  In order to perform intermittent discharge more surely, it is preferable to narrow or shorten the supply path and piping communicating from the valve mechanism 3 to the reaction vessel 2. Specifically, the inner diameter of the pipe or the like is preferably 0.5 to 5.0 mm. Moreover, as for the length of piping etc., 10-100 mm is preferable. In order to discharge the reaction liquid in the form of a mist, the tip may be made into a nozzle shape, for example, by reducing the inner diameter of a pipe or the like at the tip.

  The valve mechanism 3 is preferably one that can be opened by a minute opening time. For example, a small electromagnetic valve can be used. At that time, from the viewpoint of suppressing power consumption of the hydrogen generator, one that opens when a voltage is applied is preferable. As a structure of such an electromagnetic valve, for example, a core material is loosely inserted in a coil, the core material is urged to a valve seat as a valve body, and a core material such as metal is generated by a magnetic field generated in the coil when a voltage is applied. And a mechanism having a mechanism for opening the valve by being displaced.

  The hydrogen gas generated in the reaction vessel 2 is supplied to the power generation unit B. In the power generation unit B, a plurality of fuel cells 4 are connected in series. As a specific configuration of the fuel battery cell 4, for example, a fuel battery cell disclosed in Utility Model Registration No. 3114148 can be used. The fuel cell 4 includes a plate-shaped solid polymer electrolyte, and cathode and anode side electrode plates (gas diffusion plates) arranged on both sides so as to sandwich the solid polymer electrolyte. Further, a cathode side / anode side metal plate is provided outside. A gas flow path for flowing hydrogen gas is formed inside each fuel cell 4, and it is possible to take out an electrical output by supplying hydrogen gas to the fuel cell 4.

  The booster circuit 5 boosts the output voltage from the power generation unit B so as to be a predetermined voltage, and is constituted by a DC-DC converter or the like. The degree of pressure increase is determined according to the requirements of the equipment in which this fuel cell is used. The stabilization circuit 6 stabilizes the voltage boosted by the boost circuit 5 and supplies power to the device via the electrical output unit 7. As the electrical output unit 7, a terminal unit that can be connected to a USB terminal, a charging terminal of a mobile phone, or the like is provided.

  The valve control unit 8 performs opening / closing control of the valve mechanism 3 described above. The timing of the opening / closing control is controlled based on the setting means 9. In the setting means 9, for example, the time for opening the valve mechanism 3, the opening time, the time interval until the next opening, and the like are set. Various modes of setting the opening / closing timing are conceivable. Examples thereof include the following. One is a method of controlling opening and closing at a preset interval. When preset, the interval (cycle) for opening the valve mechanism may be constant or variable. In this case, the opening / closing timing can be set in advance by a program (software).

  The other method is a method of dynamically setting the opening / closing timing. For example, it is a method of setting in real time so that an appropriate amount of hydrogen gas can be generated while monitoring the generation amount of hydrogen gas, the output voltage or output current of a fuel cell supplied with hydrogen gas, and the like. Thus, various modifications can be considered for the setting by the setting means in the present invention.

  In the present invention, the reaction liquid is intermittently discharged into the reaction container by the reaction liquid supply mechanism so that at least the initial discharge amount of the reaction liquid is 10 μL or less. In the present invention, from the viewpoint of enhancing the responsiveness of the hydrogen generation amount while controlling the reaction mildly, the discharge amount of the reaction liquid for one batch is preferably 5 μL or less, and more preferably 2 μL or less.

  In the illustrated example, the valve mechanism 3 is intermittently controlled to open and close so as to achieve such a discharge amount. The amount of discharge of the reaction liquid at one time during the opening time of the valve mechanism 3 is affected by the pressure on the primary side of the valve mechanism 3, the property of the supply path between the valve mechanism 3 and the reaction vessel 2, and the like. It can be controlled by the opening time of the section 8. At that time, from the viewpoint of improving the responsiveness of the hydrogen generation amount while controlling the reaction mildly, the valve control unit 8 intermittently moves the valve mechanism 3 so that the initial opening time is within 60 milliseconds. It is preferable to control opening and closing, more preferably within 30 milliseconds, and even more preferably within 10 milliseconds. On the other hand, 1 millisecond or more is preferable and 2 milliseconds or more is more preferable from the viewpoint of performing an appropriate reaction with one discharge.

  The valve opening / closing control is performed intermittently, for example, preferably at intervals of 0.1 to 10 seconds, and more preferably at intervals of 0.5 to 5 seconds. In addition, the valve mechanism 3 may be opened at a constant interval. For example, the valve mechanism 3 may be variably set to be long at first and gradually shortened. By such program control, even when the pressure on the primary side of the valve mechanism 3 gradually decreases during the discharge of the reaction liquid, the discharge amount per unit time can be made more constant. The opening time of the valve mechanism 3 may be variable, but it is preferable to set the opening time constant in order to simplify the control.

  When a reaction liquid is discharged with a more constant discharge rate per unit time for a highly reactive hydrogen generator, the hydrogen generation flow rate per unit time generally tends to decrease in the latter half of the reaction. For this reason, for example, when the hydrogen generation flow rate per unit time is kept constant, in the latter half of the reaction, the opening time of the valve mechanism 3 is shortened, the opening timing (cycle) is shortened, or both It is preferable to increase the supply amount of the reaction liquid per unit time by the combination. Thereby, the hydrogen generation flow rate per unit time can be kept more constant.

  The setting of the opening / closing timing by the setting means 9 may be a setting by software or a setting by hardware.

  The external power supply 10 is composed of a plurality of button batteries, and is used to operate the valve mechanism 3 when the fuel cell is started. Once the power generation by the power generation unit B is started, the external power supply 10 is unnecessary, and the drive control of the valve mechanism 3 can be performed using the electrical output by the power generation unit B itself. For this purpose, a switching unit 11 is provided, and the valve control unit 8 performs switching control of power generation by the external power source 10 and the power generation unit B.

  Further, the valve control unit 8 monitors the output voltage value from the power generation unit B, and can also control the valve mechanism 3 so as to obtain an appropriate voltage value. Thereby, it becomes possible to control the generation amount of hydrogen gas by adjusting the amount of water to be discharged.

<Action>
The operation of the fuel cell configured as described above will be described. First, for example, it is necessary to store, for example, water in the liquid storage container 1. Before the water is stored, the liquid storage container 1 is in a deflated state due to its own elastic restoring force. Therefore, water is injected into the liquid container 1 using the syringe 12. The liquid container 1 is made of a material having an elastic restoring force. In particular, the liquid container 1 is partially provided with a material that does not leak water even when the needle of the syringe 12 is taken in and out. Can be prevented. By adding water, the liquid container 1 can swell in a balloon shape against the elastic restoring force.

  For example, if 3 cc of water is used, a little more 3.5 cc of water is injected during the first injection, and 3 cc of water is injected after the second injection. This is because a stable elastic restoring force can be obtained by initially injecting a large amount and shifting the material to the yield point side and extending the material. That is, when water is discharged, it is preferable not to cause a large difference in elastic restoring force between the start of use and the end of use. Thereby, water can be discharged in a stable state.

  The method for injecting water into the liquid container 1 is not limited to the above. For example, the valve mechanism 3 is set in an open state, and water is injected into the liquid container 1 from the valve mechanism 3 side. You may do it.

  When the injection of water is completed as described above, it is necessary to open the valve mechanism 3 and supply water at the start of use of the fuel cell. At first, since a power source for driving the valve mechanism 3 is required, the valve mechanism 3 is driven using the external power source 10 to discharge a predetermined amount of water to the reaction vessel 3 side. Thereby, hydrogen gas is generated by a chemical reaction in the reaction container 3, and the hydrogen gas is supplied to each fuel cell 4 of the power generation unit B. As a result, the electrical output is taken out, and once the electrical output is taken out, the valve mechanism 3 can be driven using the electrical output, so the external power source 10 becomes unnecessary. Thereafter, the opening / closing control of the valve mechanism 3 is performed according to the setting by the setting means 9, and the electrical output is taken out.

<Hydrogen generation method>
The hydrogen generation method of the present invention is characterized in that it includes a step of intermittently supplying the reaction solution to the hydrogen generating agent so that the discharge amount of the reaction solution at least once in the initial stage is 10 μL or less. The present invention is particularly suitable when the hydrogen generator contains calcium hydride, lithium hydride, potassium hydride, sodium borohydride, potassium borohydride, lithium aluminum hydride, sodium aluminum hydride, or magnesium hydride. It is valid. The hydrogen generation method of the present invention can be preferably carried out using the above-described hydrogen generation apparatus of the present invention. The conditions for hydrogen generation and the like are as described above.

  In the present invention, it is particularly preferable to supply the reaction liquid by intermittently opening and closing the valve mechanism so that at least the initial opening time is within 60 milliseconds. Moreover, it is preferable that the reaction liquid discharged to a hydrogen generating agent is discharged in mist form.

<Another embodiment>
The device in which the fuel cell according to the present invention is used is particularly suitable for portable devices, but is not limited to this, and can be used for various devices. Further, the use purpose of the fuel cell may be used as a main power source of the device, or may be used for the purpose of charging a secondary battery used in the device. Further, when the fuel cell is attached to or detached from the device, the fuel cell may be connected to the device via a connection cord instead of being directly attached to the device (terminal exposed outside the device).

  As a liquid container, you may comprise by things other than the member which has elasticity. For example, a resin or metal container may be used, and a structure in which an external force is applied to water contained therein by a spring or other means may be used. FIG. 2 is a diagram showing an example of the configuration, and a pressing force is applied to water by a coil spring 14 through a pressing plate 13.

  FIG. 3 is a diagram showing another embodiment when water is discharged into the reaction vessel 2. In this configuration example, an intermediate container 15 is provided, and water in the intermediate container 15 is discharged to the reaction container 2 side by operating the piston 16. That is, first, a fixed amount of water is accommodated in the intermediate container 15, and then the piston 16 is pushed to discharge the fixed amount into the reaction container 2. Thereby, a fixed amount of water can be discharged accurately.

  FIG. 4 is a view showing still another embodiment when water is discharged into the reaction vessel 2. The liquid container 1 is formed of a deformable member (for example, a rubber material such as natural rubber or silicon rubber). The liquid container 1 is given a discharge force for water by a pressing plate 19, a support plate 20, and a spring 18 (corresponding to an urging means). The spring 18 biases the pressing plate 19 downward in the figure. FIG. 4A shows an initial state, and FIG. 4B shows a state after about half of the water has been discharged. Each time water is discharged, the pressing plate 19 gradually falls downward.

  FIG. 5 shows the relationship between the passage of time and the amount of water discharged in the configuration shown in FIG. It is assumed that the opening time of the valve mechanism 3 is constant. From such a relationship, it is preferable to shorten the ON (opening) interval of the valve mechanism 3 as time passes.

  FIG. 6 is a view showing still another embodiment when water is discharged into the reaction vessel 2. Since the liquid container 1 has a bellows-shaped side wall and uses a flexible material, the container volume can be easily changed by expansion and contraction of the bellows. Examples of the flexible material include resins such as polyolefin and polyurethane, and rubber materials such as natural rubber and silicon rubber. Moreover, you may use a bag-shaped flexible material without providing a bellows, and in that case, since there is no bellows part, volume efficiency can be improved more.

  A rubber stopper 22 is provided at the outlet 1 a of the liquid storage container 1, and water can be supplied from the liquid storage container 1 to the valve mechanism 3 by inserting a needle-like pipe 23. As a material constituting the rubber stopper 22, a rubber material such as natural rubber or silicon rubber can be used.

  The liquid storage container 1 is given a discharge force against water by the pressing plate 19, the upper surface 21 a of the outer container 21, and the spring 18 (corresponding to an urging means). The spring 18 biases the pressing plate 19 downward in the figure. The side wall of the pressing plate 19 is slidable (low friction) with respect to the side wall 21b of the outer container 21, and since there is play in both, the pressing plate 19 can move up and down without resistance. FIG. 6 shows an initial state. Each time water is discharged, the pressing plate 19 gradually falls downward.

  In the present embodiment, the setting of the opening / closing timing by the setting means 9 is performed according to preset contents, but the present invention is not limited to this. The valve mechanism 3 may be controlled dynamically (in real time) so that an appropriate output can be obtained by constantly monitoring the output voltage value (or current value). In this case, the opening period of the valve mechanism 3 may be lengthened or shortened.

  Examples and the like specifically showing the configuration and effects of the present invention will be described below. In addition, the evaluation item in an Example etc. measured as follows.

(1) Hydrogen generation flow rate After the generated hydrogen gas was dried through a silica gel dryer, the instantaneous flow rate of hydrogen gas and the total amount of hydrogen generation were measured with a mass flow meter (manufactured by KOT-LOC).

(2) Discharge amount The water discharge test is performed with the equipment and conditions used in the examples, the discharged water is received by a receiver, the mass is measured every 10 minutes, and the total discharge amount and one discharge The amount was calculated.

Example 1
The apparatus shown in FIG. 6 was used for supplying the reaction solution. The volume of the liquid container 1 in the empty state is 2.5 cc, and 2.0 cc of water is set therein. Further, the urging force of the spring 18 was set so that the initial water pressure in the liquid container 1 was 30 KPa. On the other hand, a cotton-like sheet (thickness 0.5 mm) is placed inside a reaction vessel 2 (inner dimensions 21 mm × 21 mm × 8 mm) having a hydrogen gas discharge port at the bottom of the vessel, and calcium hydride (sum) 1.2 g (made by Kojun Pharmaceutical Co., Ltd., particle size of 2 mm or less) was added, and the same cotton-like sheet as described above was placed on the top, and connected so that the pipe from the valve mechanism 3 faced the upper surface of calcium hydride. .

  Using this device, the opening / closing timing is set to be fixed at an opening time of 6 milliseconds at intervals of 2 seconds, the opening / closing control of the valve mechanism 3 is performed, and the relationship between the number of opening / closing of the valve and the total discharge amount of water is determined in advance. Examined. The result is shown in FIG. As shown in the figure, the urging force of the spring 18 decreases as the total discharge amount increases, so that the increase rate of the total discharge amount (that is, the single discharge amount) decreases. In addition, the discharge amount of one time in this discharge test was 6 μL in the initial stage.

  Next, even if such a single change in the discharge amount occurs, the opening / closing timing interval of the valve mechanism 3 is gradually shortened so that the discharge amount per unit time is constant (1.0 cc / hour). By performing the program control, the opening / closing timing of the valve mechanism 3 is set so that the relationship (proportional relationship) between time and the total discharge amount of water as shown in FIG. 8 is obtained. The opening / closing timing after 1 hour in the program control of this setting was every 2 seconds.

  With this setting, water was supplied to calcium hydride in the reaction vessel to generate hydrogen gas at room temperature. The reaction liquid discharged to the hydrogen generating agent was mist. FIG. 9 shows changes with time in the instantaneous flow rate of hydrogen gas and the total amount of hydrogen generation at that time. As is clear from FIG. 9, it was found that the instantaneous flow rate of hydrogen gas was constant from the start of the reaction to 40 minutes, but gradually decreased thereafter.

Example 2
In order to reduce the decrease in the hydrogen generation rate after 40 minutes from the start of the reaction in Example 1, the opening / closing timing is set so that the amount of water discharged per unit time is larger in the second half of the reaction than in the first half of the reaction. The program was changed. Specifically, as shown in FIG. 10, the opening / closing timing (opening) is such that the discharge rate is 1.0 cc / hour for 30 minutes from the start of the reaction and the discharge rate is 1.1 cc / hour after 30 minutes. Time fixed at 6 milliseconds). The opening / closing timing after 1 hour in the program control of this setting was an interval of 1.5 seconds.

  Program control was performed with this setting, and water was supplied to calcium hydride in the reaction vessel to generate hydrogen gas at room temperature. The reaction liquid discharged to the hydrogen generating agent was mist. FIG. 11 shows changes with time in the instantaneous flow rate of hydrogen gas and the total amount of hydrogen generation at that time. As is apparent from FIG. 11, the instantaneous flow rate of hydrogen gas was constant after 40 minutes from the start of the reaction.

Example 3
In Example 1, hydrogen gas was generated in the same manner as in Example 1 except that 0.6 g of lithium hydride (manufactured by Wako Pure Chemical Industries, Ltd., particle size of 2 mm or less) was used instead of calcium hydride. It was. As a result, as in Example 1, the instantaneous flow rate of hydrogen gas was substantially constant (within 5% of the average value) from the start of the reaction to 60 minutes.

Comparative Example 1
In the first embodiment, the opening time of the valve mechanism 3 is set to 0.02 seconds (a single discharge amount is 20 μL at an initial stage), and the discharge amount per unit time is the same (1. Hydrogen gas was generated in the same manner as in Example 1 except that it was set to be constant at 0 cc / hour. As a result, the instantaneous flow rate of hydrogen gas changed greatly at the initial stage (500% or more of the average value), and it was at a level that could not withstand practical use.

Reference example 1
Examples As the hydrogen generating agent, sodium hydride (manufactured by Wako Pure Chemical Industries, Ltd., TSN0145), lithium hydride (manufactured by Wako Pure Chemical Industries, Ltd., CEJ7561), and calcium hydride (manufactured by Chemetall Inc., 46960) were each used in an amount of 0.5 g. Hydrogen gas is generated by placing in the same reaction vessel as 1 and supplying water with a syringe pump at a supply rate of 1.5 mL / h (1.3 mL / h for calcium hydride). I let you. FIG. 12 shows changes with time in the total hydrogen generation amount and hydrogen generation flow rate at that time.

  From this result, sodium hydride and calcium hydride show high reactivity from the graph of total hydrogen generation amount, and from the graph of hydrogen generation flow rate, hydrogen gas suddenly appears immediately after the start of the reaction when supplied by a syringe pump. It was found to occur.

Conceptual diagram showing the configuration of a hydrogen generator and a fuel cell system including the hydrogen generator The figure which shows another embodiment of a liquid container The figure which shows another embodiment in the case of discharging | emitting water to a reaction container The figure which shows another embodiment of a liquid container Diagram showing the relationship between the amount discharged from the liquid container and time The figure which shows another embodiment of a liquid container The graph which shows the relationship between the valve opening / closing number in Example 1, and the total discharge amount of water. The graph which shows the relationship between the time in Example 1 and the total discharge amount of water The graph which shows the time-dependent change of the instantaneous flow volume of hydrogen gas in Example 1, and hydrogen generation total amount. The graph which shows the relationship between the time in the program of the opening / closing timing of Example 2, and the total discharge amount of water The graph which shows the time-dependent change of the instantaneous flow volume of hydrogen gas in Example 2, and hydrogen generation total amount. The graph which shows the time-dependent change of the total hydrogen generation amount and hydrogen generation flow rate of hydrogen gas in Reference Example 1

Explanation of symbols

A Hydrogen generator B Power generation unit 1 Liquid container 2 Reaction container 3 Valve mechanism 4 Fuel cell 8 Control unit 9 Setting means 10 External power supply 12 Syringe

Claims (4)

In a hydrogen generator comprising: a liquid container that contains a reaction liquid; a reaction container that contains a hydrogen generating agent; and a reaction liquid supply mechanism that supplies the reaction liquid in the liquid container to the reaction container.
The hydrogen generator contains calcium hydride, lithium hydride, or sodium hydride,
The reaction liquid supply mechanism includes a valve mechanism for intermittently discharging the reaction liquid, a valve control unit that controls opening and closing of the valve mechanism, and a pressure mechanism that pressurizes the primary side of the valve mechanism. , the discharge amount of one time of the reaction solution at least initially is as 10μL follows and opening time is within 60 milliseconds, for intermittently discharging the reaction liquid was intermittently controls the opening and closing of the valve mechanism to the reaction vessel A hydrogen generator characterized by that. The hydrogen generation apparatus according to claim 1 , wherein the liquid container is formed of a deformable member, and the pressurizing mechanism includes a biasing unit that biases the deformable member. Using a reaction liquid supply mechanism comprising: a valve mechanism for intermittently discharging the reaction liquid; a valve control unit that controls opening and closing of the valve mechanism; and a pressurizing mechanism that pressurizes the primary side of the valve mechanism. Valve mechanism so that the discharge amount of the reaction liquid for at least the initial batch of the hydrogen generator containing calcium hydride, lithium hydride, or sodium hydride is 10 μL or less and the open time is within 60 milliseconds. A hydrogen generation method for intermittently controlling opening and closing of the gas and supplying the reaction solution intermittently. The hydrogen generating method according to claim 3 , wherein the reaction liquid discharged to the hydrogen generating agent is discharged in a mist form.

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