WO2015026292A1

WO2015026292A1 - Process and apparatus for generating hydrogen

Info

Publication number: WO2015026292A1
Application number: PCT/SG2014/000104
Authority: WO
Inventors: Zhijun Gu
Original assignee: Horizon Fuel Cell Technologies Pte. Ltd.
Priority date: 2013-08-22
Filing date: 2014-03-04
Publication date: 2015-02-26
Also published as: SG2013064043A

Abstract

For generating hydrogen particularly for feeding a fuel cell, liquid solutions (4, 5) of a chemical hydride and of a accelerator or pre-accelerator are fed to a reaction site (11, 12, 13) via a peristaltic pump (9) and thereby commingled at a constant mutual ratio and so that the control of the reaction that leads to the release of the hydrogen can be conveniently performed by varying the pump speed and the duty cycle of a start and stop operation of the pump, while also regulating the temperature and the pressure at the reaction site.

Description

PROCESS AND APPARATUS FOR GENERATING HYDROGEN

FIELD OF THE INVENTION

The invention relates to a process for generating hydrogen by reacting a chemical hydride in the presence of an accelerator, both the hydride and the accelerator each being a component in a liquid mixture, the mixtures being fed to a reaction site and commingled to start and carry on the reaction, and to an apparatus for carrying out the process, comprising sources of liquid mixtures both of a chemical hydride to be reacted and of an accelerator for the reaction, and a reaction site where the liquid mixtures are commingled.

BACKGROUND OF THE INVENTION

It is known that a hydrogen storing tank having a high demand of volume will be necessary for a general practical use of hydrogen operated fuel cells. The volume of such hydrogen storing tank can be reduced by storing a solid or liquid chemical precursor of hydrogen, generating the hydrogen upon demand only. Such chemical precursor, according to common prior art, e.g. is a metal boron hydride, see US 2007068071 A1

A process and an apparatus as stated above are known from WO

2006/135895 A2, see particularly page paragraphs [0023] and [0024]. In this publication, the accelerator liquid - termed therein reactant - is e.g. an aqueous solution of cobalt chloride CoCI₂ and the hydrogen-bearing fuel preferably is a solid but is mentioned to also be a liquid such as an aqueous solution of sodium borohydride (NaBH₄). The author of the prior art publication, however, prefers the solid fuel. Solid fuel, however, has the consequence of a more difficult control of the reaction. A precise control is desirable particularly for the supply of fuel cells where the hydrogen supply has to follow the fluctuating consumption of electrical power.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a process and an apparatus for a hydrogen generation precisely and optimally controlled throughout the different operational demands. To attain this object, in a hydrogen generator of the invention, the process to be carried out is characterized in that the hydride, and the accelerator in the respective commingled mixture are fed, through the whole duration of the reaction, under a constant mutual ratio and that both have a constant concentration or vary direct proportional to each other. The liquid mixtures which are taken from respective sources are each pumped to the reaction site, and preferably, the liquid mixtures are taken from respective tanks, and pumped by at least one peristaltic pump. The respective sources, at least the hydride are actively kept within a predefined temperature range between 20°C and -20°C, preferably between 5°C and 0°C before starting the hydrogen generator, thus minimizing the self-decomposition of the hydride.

Since the reaction also originates some liquid exhaust, it is further preferred that such exhaust, as a by-product resulting from the reaction, is pumped off from the reaction site by the or one of the peristaltic pump(s) that also pump(s) the liquid mixtures to the reaction site. Under the supposition that the chemical hydride is NaBH₄ and the accelerator is CoCI₂, the concentrations and the mutual ratio are recommended such that the weight ration of NaBH₄ and C0CI₂ is from 13:1 to 30:1 , so as to allow a comfortable control under usual conditions. A nominal and an effective concentration can be distinguished, the nominal concentration being the one of the hydride in the liquid fuel solution and the effective concentration being the one of the hydride after addition of the accelerator solution. To have a high effective concentration, the nominal concentration is to be increased and the mix ratio is to be chosen high, i.e. as high as possible as long as the accelerator is enough for the reaction. The limit for the nominal concentration is 34% at room temperature but can be higher at higher temperature. The mix ratio can be to above 10:1. By carrying out the defined process, a control is possible of the speed of generation of the hydrogen by varying the working speed of the pump and the duty cycle of a start and stop operation the pump is subjected to. Under the supposition that the chemical hydride is NaBH₄ and the accelerator is malic acid, the concentrations and the mutual ratio are such that the weight ratio of NaBH₄ and malic acid is not more than 0,6 to 1. To reach a high nominal concentration, also a solid chemical hydride can be mixed with water on demand thus further minimizing the self-decomposition of the chemical hydride. For carrying out such process, an apparatus, according to the invention, has tanks as its sources, wherein the hydrogen tank comprises cooling devices, that are both, the hydrogen and accelerator tank, connected via tube lines and a pumping means to a reaction site, wherein preferably the pumping means is at least one peristaltic pump comprising a flexible tubing or hose which is integrated into the respective tube line of one of the liquid mixtures. For having a compact and non-complex device, it is preferred that a single peristaltic pump comprises two tubings or hoses each integrated into one of the tube lines. The flexible tubings or hoses within the - respective - peristaltic pump(s) have, for the different mixtures, sectional areas proportional to the respective component according to the constant mutual ratio. Possibly a third, flexible tubing or hose in the single peristaltic pump is integrated into a tube line carrying liquid exhaust of the reaction away from the reaction site.

For further compactness, the apparatus according to the invention, comprises, if the chemical hydride is solid, a partition in its tank, which allows the mixing of the solid hydride with water only on demand.

In the apparatus, according to a convenient construction, the reaction site comprises a mixing conduit and a reaction chamber connected in series, the mixing conduit joining the pumping means, and to the reaction chamber is connected a hydrogen output conduit and an exhaust exit conduit, a filter barring any exhaust passage being preferably arranged in the reaction chamber upstream the hydrogen output conduit. The mixing conduit can be optimised by comprising a tube, having a length such that the commingled liquid mixtures run through within 60 seconds and containing some turbulence bodies such as bowls promoting the commingling.

To ensure the liquid status of the mixed reactants, i.e. the hydride and the accelerator, and to prevent their clogging, especially while starting the process, the apparatus advantageously has a shorter accelerator tube or hose compared to the hydride tube or hose, thus ensuring the accelerator reaches the mixing conduit and the respective reactor before the hydride. BRIEF DESCRIPTION OF THE DRAWING

The foregoing and further objects, features and advantages of the present invention will become apparent from the following description of a preferred embodiment with reference to the accompanying drawing. The sole Figure schematically shows an exemplary arrangement for the hydrogen generation.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

A hydrogen generator apparatus 1 , in the following termed "hydrogen generator", comprises a fuel tank 2 and an accelerator tank 3. The fuel tank 2 contains a supply of a fuel 4, which is a liquid mixture, i.e. a solution or a suspension, of a chemical hydride in a carrier liquid, in the preferred example an aqueous solution. If a solid chemical hydride is chosen, the liquid mixture is prepared on demand only by commingling the solid hydride with water, both stored in the fuel tank 2, thus the tank 2 comprises two partitions or storage chambers (not shown in the figure). Suitable chemical hydrides include, but are not limited to, sodium borohydride, aluminium borohydride hydrides, lithium borohydride, lithium aluminium. The preferred chemical metal hydride is sodium borohydride NaBH4 at a rate of 5% to the solubility limit in water.

Optionally an additive is further applied to avoid a reaction of the metal hydride with the already present water. Suitable additives are such, that enlarge the OH^" concentration, the preferred additive is NaOH in the mixing rate of 0.5 to 5wt %. Further the fuel tank 2 comprises cooling devices (not shown in the figure) to keep the hydride temperature within a predefined range from 20°C to -20°C, preferably from 5°C to 0°C when the hydrogen generator 1 is shut off. This cooling can also be done by storing the tank 2 in a cooled environment, thus minimizing the self-decomposition of the hydride and enhancing storing time or lifetime of the hydrogen generator 1 respectively.

The accelerator tank 3 contains a liquid too. It can be a catalyst or pre- accelerator liquid 5, and consists of water and preferably of a transition metal from the group VIII B, I B or II B of the periodic table of elements; for example the accelerator may include transition metals such as cobalt (Co), nickel (Ni), ruthenium (Ru), platinum (Pt), iridium (Ir); or copper (Cu), silver (Ag); or zinc (Zn). A pre-accelerator to be decomposed resulting in metal ions which originate the catalytic effect, can be a metal chloride. The preferred pre-accelerator is cobalt-2- cloride (C0CI₂) at a rate of 3 to 30%. The proper accelerator, i.e. the substance causing the catalytic activity, is metallic cobalt present after a decomposition of the pre-accelerator C0CI2.

The liquid in the accelerator tank 3 can alternatively be an acidic solution, comprising any suitable acid, e.g. inorganic acids such as mineral acids, hydrochloric acids (HCL), sulphuric acids (H2SO4) and phosphoric acids (H3PO4), and organic acids such as acetic acids (CH3COOH), formic acids (HCOOH), maleic acid, tartaric acids or preferably citric acids in a 10 to 50% solution and more preferably malic acid in a 5 to 35% solution.

The fuel 4 and the accelerator liquid 5 are pumped via a fuel conduit 6 and an accelerator conduit 7 out of their storage chambers in the tanks. The used pump can be a gear pump with one or more pairs of gears driven by one shaft or preferably a peristaltic pump 9. Peristaltic pumps are displacement pumps used for pumping a fluid contained within a flexible tubing or - for higher pressure - a flexible hose, or more than one tubing or hose, by moving one or several rollers or shoes 10, in the drawing two rollers, over the tubing or hose, compressing it and causing a zero diameter location to run along the tubing, pushing the fluid. Usual peristaltic pumps have a circular pump casing and a rotor carrying a number of rollers, linear constructions however are also known. In the drawing, for better illustration, a cylindrical back wall whereupon the tubings are backed up is omitted. The peristaltic pump 9 pumps the fuel 4 and the accelerator liquid 5 to a reaction site consisting of a combination point 1 , a mixing conduit 12 and a reaction chamber 13.

The shorter accelerator conduit 7 compared to the fuel conduit 6 ensures that the accelerator liquid 5 reaches the combination point 1 1 in advance of the fuel 4, thus avoiding a clogging of both liquids 4, 5 in the mixing conduit 12 and the reaction chamber 13 respectively.

In one described example, the mixing conduit 12 includes movable or non- movable parts, here in the form of ceramic bowls 14 to elongate the commingling time and enhance the intensity of the commingling process.

To the reaction chamber 13, via a filter unit 15, which is placed within the reactant chamber 13 to filter the gaseous parts, i.e. hydrogen and water, a hydrogen output 16 is connected for issuing the useful product H₂. Further connected to the reactant chamber 13 is an exhaust exit conduit 20, diverting the reaction exhaust which is when using NaBH₄ as fuel and C0CI₂ as accelerator, a liquid exhaust 21 mainly consisting of NaB02, cobalt and water. The exhaust 21 is pumped out of the reaction chamber 13 via the exhaust exit conduit 20 into an exhaust chamber 22. There it can be stored e.g. for later recycling or it can also be discharged to the environment; in this case the exhaust chamber 22 symbolizes the environment. This has advantages in applications like vehicles or unmanned aerial vehicle (UAVs) where weight is a critical issue/ Therefore it is necessary that the exhaust 21 is kept liquid in the reactant chamber 13 and also should not solidify in the exhaust exit conduit 20. To keep a proper temperature for avoiding excessive vaporization and consequent solidification, as a cooling mechanism a blower 23 is installed at the reaction chamber and/or at the mixing conduit and is controlled via a temperature sensor in the reaction chamber by a control unit 24.

In the described example, one pump only supplies both liquids 4 and 5. The rollers 10 compress three tubings 25, 26 and 27, tubing 25 being inserted into fuel conduit 6, tubing 26 being inserted into accelerator conduit 7, and tubing 27 being inserted into exhaust exit conduit 20, the latter connected in opposite direction compared to tubings 25 and 26. Alternatively more than one pump can be used, one or two for pumping in the fuel 4 and the accelerator liquid 5 and one for pumping out the exhaust 21. In this case a liquid level sensor is set inside the reaction chamber 13 and both pumps are also controlled according to the predefined level, and preferably the exhaust is pumped out continuously at a slow rate and the speed of the pump will be enhanced if the liquid level in the reaction chamber 13 is above the pre-defined level.

In the pump 9, the diameters of the tubings in the peristaltic pump define the ratio of the flow of the liquids, i.e. of the fuel 4 and the accelerator liquid 5, resulting in the composition of a reactant at the pump outlet and combination point 11 which reactant is directed via the mixing conduit 12 to the reaction chamber 13. The diameters of the tubings 25 and 26 are thus of particular importance. Since the pump 9 is a peristaltic pump that pumps simultaneously both liquids 4 and 5 to the combination point 11 and further to the reaction chamber 13 at a pre-defined ratio, defined by the both diameters of the tubings 25 and 26, the admission ratio of fuel and accelerator is constant. Preferably, the ratio of the volumes of the fuel 4 and the accelerator liquid 5, if NaBH₄ and CoCI₂ are used, is in the range of 1 :1 to 20:1 , most preferably the ratio is 10:1. If the accelerator liquid 5 is malic acid, the concentrations and the mutual ratio are such that the weight ratio of sodium borohydride and malic acid is not more than 0,6 to 1. The pump 9 can be driven in a start and stop operation. Thus both the speed of the pump 9 and the duty cycle of the start and stop operation determine the flow and start and stop of the hydrogen release of the commingled reactant, such that the speed and the duty cycle of the pump 9 determine the volume of reactant and thus the volume of the released hydrogen. The use of only one pump to supply both the fuel 4 and the accelerator liquid 5 to the reaction chamber 3 makes the system less complex and saves weight. Since in the described example, to pump out the exhaust 21 the same pump 9 is used as for pumping in the fuel 4 and the accelerator liquid 5, the diameter of the tubing 27 defines the volume of the pumped-out exhaust because the motor of the peristaltic pump 9 drives all three liquids 4, 5 and 21 in the defined directions simultaneously. The relationship of the diameters of the tubings 25, 26 and 27 is preferably the following: the sum of the diameters of the tubings 25 and 26 is equal or slightly more than the diameter of the tubing 27. This is possible because steam passes through the filter unit 15 and the hydrogen output 16 together with the released hydrogen. On the other hand there could be some hydrogen losses if unreleased hydrogen escapes through the exhaust exit conduit 20, but this loss can be controlled to be below 10 %, usually below 3%.

In the reaction chamber 13 two main reaction parameters have to be controlled while varying the pump speed and the duty cycle of the pump 9. The one is the temperature. When fuel 2 and accelerator 3 are combined, first in the mixing conduit 12, the temperature will rise within the first 10 to 30 seconds up to a certain predefined level, preferably 95°C. On the other hand with higher temperature, i.e. at nearby 100°C, most of the water will evaporate thus the exhaust 21 will tend to crystallize in the reaction chamber 13, even though that warm water can keep a liquid stage of the exhaust 21 longer than cold water. But this second effect is minor compared to the negative evaporation effect. It has been shown that temperatures of 70 to 95 °C, preferably 90°C, if the accelerator is CoCI₂ dissolved in water, balances the effects to maximize the hydrogen release and to minimize the danger of crystallizing, and it could be avoided that unreleased hydrogen reaches the exhaust conduit 20. The optimum pre-defined 0104 temperature value varies with the chosen accelerator 3 and/or the chosen fuel 2 and its concentrations and its mutual mixing ratio. To keep the temperature at this pre-defined optimum value, the blower 23 is installed.

The second reaction parameter is pressure. It is a goal of the hydrogen generator 1 to keep the composition of its reaction product at an optimum, this means maximum hydrogen atoms and minimum water molecules per volume. If pressure in the reaction chamber 13 rises, more hydrogen than water per volume can be dispensed. A further positive effect of pressure is that it helps to avoid the crystallisation of the exhaust. On the other hand pressure in the reaction chamber 13 makes the system and its handling more complex and increases production costs. So the optimum pressure value in the reaction chamber 13 will be at about 200 to 1000 kPa above atmosphere, preferably at 300 kPa. The pressure in the reaction chamber 3 changes together with the change of hydrogen release. At high release rates pressure rises, at low release rates pressure drops. To keep the pressure in the reaction chamber 3 at a pre-defined value, the control unit 24 will modify the pump speed to compensate this change. A pressure sensor inside the reaction chamber 13 measures the pressure value. If the pressure is below the pre-defined value the pump 9 will pump in more fuel 4 and accelerator liquid 5, if pressure is above the set value the pump 9 will stop.

If more than one pump is used, i.e. an extra one for pumping out the exhaust 21 , and the liquid level sensor is set inside the reaction chamber 13, this pump can be controlled according to the pre-defined exhaust level. Conveniently the exhaust is pumped out continuously at a slow rate and the speed of the pump will be enhanced if the liquid level in the reaction chamber 13 is above the pre- defined level. The purpose of this continuously pumping out is to avoid a blocking of the exhaust conduit by crystallization of the exhaust. This means also that the temperature of the exhaust conduit 20 needs to be kept above the crystallization temperature value of the exhaust. Insulation of the exhaust conduit 20 is sufficient in most cases, but additionally a heating mechanism can be installed. Further the use of PTFE tubes or PTFE coated tubes for the exhaust conduit 20, totally or preferably at the end of the exhaust conduit 20, helps to avoid its blocking.

o EXAMPLE 1 :

As fuel a mixture with 25% NaBH₄, 1 % NaOH and 74% water is used. The accelerator mixture, here a catalyst, comprises 10% of C0CI₂ in water. The fuel and accelerator liquid are mixed at a fixed rate of 0:1. As the fuel tubing 25 a tube with a diameter of 4.8 mm, and as the accelerator tubing 26 a tube with 1.5 mm diameter is used. The peristaltic pump 9 is running to provide 1 litre of fuel 4 and 0.1 litre of accelerator liquid 5 per 30 min to the mixing conduit 12 that has a length of 150 mm, a diameter of 25mm and is filled within the first 30 mm of its volume with the ceramic bowls 14 which have a diameter of 3,5 mm. In this time most of the chemical stored hydrogen can be released. If the applied pressure is 400 kPa above atmosphere and the reaction temperature in the reaction chamber is kept at 100°C, in total about 550 litre of hydrogen can be supplied to an intermediate storage device. The total hydrogen losses of this process can be kept lower than 5% of the effective hydrogen storage concentration of the reactant. The residual reactant, that has nearly no more hydrogen stored with, will be pumped out of the reaction chamber 13 by the one and only peristaltic pump 9 through the exhaust exit conduit 20, that is a PTFE tube with a diameter of 4.2 mm, to the exhaust chamber 22 where it can be stored.

EXAMPLE 2:

As fuel 4 a mixture with 20% NaBH₄, 2 % NaOH and 78% water is used. Before starting the hydrogen generator 1 , the fuel tank 2 is cooled to 3°C. The accelerator mixture comprises a 35% solution of malic acid in water. The fuel 4 and accelerator liquid 5 are mixed at a fixed rate of 1 : 1. As the fuel tubing 25 and the accelerator tubing 26 a tube with an inner diameter of 3,2mm is used, while the accelerator tubing 26 is 30cm shorter than the fuel tubing 25. The peristaltic pump 9 is running to provide 0,1 litres of fuel 4 and 0, 1 litres of accelerator liquid 5 per 1 min to the reactant chamber 13 directly, without having a mixing conduit 12. If the applied pressure is 100kPa above atmosphere and the reaction temperature in the reaction chamber 13 is kept at 80°C, a total of about 45 litres of hydrogen can be supplied to an intermediate storage device. REFERENCE LIST

1 hydrogen generator apparatus

2 fuel tank

3 accelerator tank

4 fuel

5 accelerator liquid

6 fuel conduit

7 accelerator conduit

9 peristaltic pump

10 roller

11 combination point

12 mixing conduit

13 reactant chamber

14 ceramic bowls

15 filter unit

16 hydrogen output

20 exhaust exit conduit

21 exhaust

22 exhaust chamber

23 blower

24 control unit

25 tubing for fuel

26 tubing for accelerator liquid

27 tubing for exhaust

Claims

1. A process for generating hydrogen by reacting a chemical hydride in the presence of an accelerator, both the hydride and the accelerator each being a component in a liquid mixture (4, 5), the mixtures being fed to a reaction site (11 , 12, 13) and commingled to start and carry on the reaction, characterized in that the hydride and the accelerator in the respective liquid mixtures (4, 5) to be commingled, are fed, through the whole duration of the reaction, under a constant mutual ratio.

2. The process according to claim 1 , characterized in that the hydride and the accelerator in the respective liquid mixtures (4, 5) have a constant concentration.

3. The process according to any of claims 1 to 2, characterized in that the hydride and the accelerator in the respective liquid mixtures (4, 5) vary direct proportional to each other.

4. The process according to any of claims 1 to 3, characterized in that the hydride is taken from a respective liquid source.

5. The process according to any of claims 1 to 3, characterized in that the hydride is taken from a respective solid source.

6. The process according to claim 5, characterized in that the solid source is mixed with water on demand.

7. The process according to any of claims 1 to 6, characterized in that the hydride is kept within a predefined temperature range before starting the process.

8. The process according to claim 7, characterized in that the predefined temperature range is between 20°C and -20°C, preferably between 5°C and 0°C.

9. The process according to any of claims 1 to 8, characterized in that the accelerator is a catalyst.

10. The process according to any of claims 1 to 8, characterized in that the accelerator is an acid.

11. The process according to any of claims 1 to 10, characterized in that the liquid mixtures (4, 5), which are taken from respective sources are each pumped to the reaction site (11 , 12, 13).

12. The process according to claim 11 , characterized in that the liquid mixtures (4, 5) are taken from respective tanks (2, 3) and pumped by at least one peristaltic pump (9).

13. The process according to any of claims 1 to 12, characterized in that the accelerator mixture (5) arrives in advance of the fuel mixture (4) at the reaction side ( 1 , 12, 13).

14. The process according to any of claims 1 to 13, characterized in that liquid exhaust (21), as a by-product resulting from the reaction, is pumped off from the reaction site ( 3) by the or one of the peristaltic pump(s) (9) which also pump(s) the liquid mixtures (4, 5) to the reaction site.

15. The process according to any of claims 1 to 14, characterized in that the liquid exhaust (21) is stored in an exhaust chamber (22).

16. The process according to any of claims 1 to 14, characterized in that the liquid exhaust (21) is discharged into the environment. 7. The process according to any of claims 1 to 16, characterized in that, if the chemical hydride is sodium borohydride and the accelerator is the catalyst cobalt chloride, the concentrations and the mutual ratio are i5/026292^{jt tne we|}9ht ration of sodium borohydride and <PCT/SG2014/OOOIO4 is from 13:1 to 30:1.

18. The process according to any of claims 1 to 16, characterized in that, if the chemical hydride is NaBH and the accelerator is malic acid, the concentrations and the mutual ratio are such that the weight ratio of NaBH4 and malic acid is not more than 0,6 to 1.

19. The process according to any of claims 1 to 18, characterized in that the speed of generation of the hydrogen is controlled by varying the working speed of the pump (9) and the duty cycle of a start and stop operation the pump is subjected to.

20. The process according to any of claims 1 to 19, characterized in that the accelerator arrives at the reaction side before the hydride.

21. An apparatus for carrying out the process of any of claims 1 to 20, comprising sources (2, 3) of liquid mixtures (4, 5) both of a chemical hydride to be reacted, and of an accelerator for the reaction, and a reaction site (11 , 12, 13) where the liquid mixtures are commingled, characterized in that the sources are tanks (2, 3) connected via tube lines (6, 7) and a pumping means (9) to the reaction site (11 , 12, 13).

22. The apparatus according to claim 21 , characterized in that the tank (2) of the chemical hydride is cooled.

23. The apparatus according to claim 21 or 22, characterized in that the tank (2) comprises two separated partitions to mix a solid hydrogen with water on demand.

24. The apparatus according to any of claims 21 to 23, characterized in that the pumping means is at least one peristaltic pump (9) comprising a flexible tubing or hose (25, 26) which is integrated into the respective tube line (6, 7) of one of the liquid mixtures (4, 5). 2015/026292 paratus according to claim 24, characterized ipcT/SG20i4/oooio4 peristaltic pump (9) comprises two tubings or hoses (25, 26) each integrated into one of the tube lines (6, 7).

26. The apparatus according to any of claims 21 to 25, characterized in that a third flexible tubing or hose (27) in the single peristaltic pump (9) is integrated into a tube line (20) carrying liquid exhaust (21) of the reaction away from the reaction site (13).

27. The apparatus according to any of claims 21 to 26, characterized in that the flexible tubing or hose (26) transporting the accelerator (5) is shorter than the flexible tubing or hose (25) transporting the hydride (4).

28. The apparatus according to any of claims 21 to 27, characterized in that the flexible tubings or hoses (25, 26) within the - respective - peristaltic pump(s) (9) have, for each mixture, sectional areas proportional to the respective component in the mixture according to the constant mutual ratio.

29. The apparatus according to any of claims 21 to 28, characterized in that the reaction site comprises a mixing conduit (12) and a reaction chamber (13) connected in series, the mixing conduit joining the pumping means (9), and the reaction chamber being connected to a hydrogen output conduit (16) and an exhaust exit conduit (20).

30. The apparatus according to claim 29, characterized in that a filter (15) barring any exhaust passage is arranged in the reaction chamber (13) upstream the hydrogen output conduit (16).

31. The apparatus according to claim 29 or 30, characterized in that the mixing conduit (12) is a tube having a length such that the commingled liquid mixtures run through within 60 seconds, and contains some turbulence bodies (14) promoting the commingling.

32. The apparatus according to any of claims 21 to 31 , characterized in that the exhaust exit conduit (20) leads the exhaust (21) to the exhaust chamber (22) where it is stored.

33. The apparatus according to any of claims 21 to 32, characterized in that the exhaust exit conduit (20) discharges the exhaust (21) directly to the environment.