Background technology
Hydrogen receives everybody and greatly pays close attention to as a kind of novel energy, development, and especially hydrogen is in fuel cell
The application of aspect even more brings prodigious convenience to everybody life.But the storage of hydrogen is to restrict fuel cell technology
A widely applied important technology bottleneck.Therefore the portable hydrogen technology of preparing developed efficiently, inexpensive is fired for pushing
The extensive use of material battery is of great significance.
To meet the application demand of portable fuel battery, corresponding original position hydrogen producing technology requires raw material to have higher production hydrogen
Capacity, simultaneous hydrogen production reaction need fast and easy.Utilize sodium borohydride (NaBH4) hydrolysis can quickly and easily prepare
Go out hydrogen:
NaBH4+4H2O→NaBO2·2H2O+4H2
The hydrogen of release is the 20.8% of solid reactant weight, is ideal hydrogen production reaction.Therefore it is directed to NaBH4
Hydrolytic hydrogen production people conduct extensive research.
NaBH4The greatest problem that hydrolytic hydrogen production faces is NaBH4It is directly reacted with water very not exclusively, NaBH4Hydrolysis can make molten
Liquid pH value increases, and the NaBH in alkaline solution4Can with quite stable exist.In order to solve this problem, common practice
It is to promote NaBH using catalyst4Hydrolysis, custom catalysts include receiving containing transition metal elements such as Ni, Co, Pt, Ru
Scale particles, such as in document Journal of Power Sources 125 (2004) 22-26, Kojima et al. is reported
One utilizes NaBH4The device for producing hydrogen of solution, utilizes Pt/LiCoO2Catalyst realizes NaBH4The properties of solution, patent
CN104888853-A (publication date 2015.09.09) utilizes the Ru nano particles catalysis NaBH being supported on graphene sheet layer4Water
Hydrogen release is solved, patent CN104056638-A (publication date 2014.09.24) is catalyzed NaBH using metal foams such as Ni, Ru4Hydrolysis is put
Hydrogen.Similar report has very much, and feature is all by NaBH4It is configured to solution with NaOH, these nano particles are supported on solid
On fixed bed reactor, work as NaBH4Aqueous solution can release hydrogen when being contacted with catalyst.
Although this method can effectively facilitate the releasing of hydrogen, disadvantage is it is also obvious that be mainly manifested in:(1) it needs
It will be first by NaBH4Wiring solution-forming stores, and carries and inconvenient for use, capacitance loss, the experimental results is caused to show NaBH4Solution
Concentration needs addition NaOH to make NaBH between 10~20%4Stablize (referring to Review literature Fuel Cells, 10
(2010), 335~350).(2) cost of transition-metal catalyst is higher, while will appear loss, inactivation during the reaction
Phenomena such as.
Although there is the report for promoting preparing hydrogen by sodium borohydride hydrolysis reaction using acid solution before this, hydrogen production efficiency is not
Height can not be applied in actual production.
In view of this, special propose the present invention.
Invention content
In order to solve traditional transition metal-catalyzed NaBH4The above-mentioned deficiency of aqueous solution hydrogen manufacturing scheme, the present invention provides
A kind of new hydrogen manufacturing material, storage, easy to carry, low production cost, moreover it is possible to hydrogen production efficiency is improved, it is environmentally friendly.
New hydrogen production material provided by the invention is a kind of composite hydrolysis hydrogen manufacturing material, including sodium borohydride (NaBH4) and
Phosphorus pentoxide (P2O5)。
The principle of the composite hydrolysis hydrogen manufacturing material is through water and P2O5Reaction generates phosphoric acid, and then activates NaBH4, carry
High and NaBH4The activity of reaction is allowed to react with water quick and completely and releases hydrogen.
Also there is document once acid solution to be utilized to promote NaBH before this4Hydrolysis, such as in document International
Journal of Hydrogen Energy 34 (2009), in 7231~7238, Akdim et al. was once reported in hydrochloric acid or acetic acid
NaBH in solution4Reaction that can be quick and complete.However compared with existing scheme, the present invention has significantly innovative and more preferable
Implementation result.
From the hydrogen storage capability angle for improving material system, P2O5Advantage be very the P it will be evident that unit mass2O5It generates
The amounts of Labile protons be up to 0.042mol H+/ g, is higher than most of solid acid and acid anhydrides, and hydrogen production efficiency greatly improves.
Therefore, P2O5Selection be NaBH absolutely not4The simple extension of acidic hydrolysis, but pass through optimum choice, and have non-
The practical value of Chang Chong great.
Preferably, the molar ratio of above-mentioned composite hydrolysis hydrogen manufacturing material, phosphorus pentoxide and sodium borohydride is more than 0:1 is less than
Equal to 1.0:1.
It is highly preferred that the molar ratio of above-mentioned composite hydrolysis hydrogen manufacturing material, phosphorus pentoxide and sodium borohydride is 0.1:1~
0.4:1
More, NaBH is added in phosphorus pentoxide4Reaction rate it is faster, while NaBH4Conversion ratio it is higher, but when five
Aoxidize two phosphorus and NaBH4Molar ratio when being more than 0.4, NaBH4Conversion ratio already exceed 90%, further increase five oxidations two
The ratio of phosphorus is difficult to further increase NaBH4Conversion ratio, the quality hydrogen content of entire material system can be reduced on the contrary.Therefore exist
In composite hydrolysis hydrogen manufacturing material, preferably the molar ratio of phosphorus pentoxide and sodium borohydride is 0.1:1~0.4:1.
By optimizing P2O5With NaBH4Ratio and control be added water amount, it is easy to achieve over 5% quality
Hydrogen output is very high level in hydrogen storage systems all at present, and produces hydrogen and be easy to control.
Preferably, above-mentioned composite hydrolysis hydrogen manufacturing material is solid forms.In practical applications, it is very not to carry acid solution
Easily, only need to carry solid and in the present invention, water is added in when use, very convenient.Importantly, and not all
Acid by solid and generation of reacting, such as common hydrochloric acid, nitric acid, sulfuric acid of water etc. is reacted with water by gas
It generates, is utilized like that in the no image of Buddha present invention.There is the acid of some solids that can have similar effect (such as oxalic acid, lemon
Acid etc.), but hydrogen production efficiency is not high.
Preferably, above-mentioned composite hydrolysis hydrogen manufacturing material, phosphorus pentoxide and sodium borohydride mix in the form of dried powder
It closes, mixed powder storing is in the container of dry sealing.Powdered form facilitates mixing and storage, and after being conducive to
Continuous plus water management hydrogen production reaction speed, avoids reacting incomplete caused by water is uneven with solid contact.
It is that water is added into the composite hydrolysis hydrogen manufacturing material of any description above the present invention also provides a kind of hydrogen production process
.This hydrogen production process can realize Portable in-situ hydrogen manufacturing, simple and convenient, and the water of addition can be pure water, can also
It is river water, the seawater of tap water or nature, there is no particular/special requirements, are suitable for the present invention.Water can disposably add
Enter, can also be gradually added.
Preferably, above-mentioned hydrogen production process, the water of addition and the mass ratio (H of sodium borohydride2O/NaBH4) it is 1:1~5:1.Control
The addition of water processed in the range, can be easily achieved the quality hydrogen output more than 5%.
Preferably, above-mentioned hydrogen production process, the coolant-temperature gage of addition is between 10~100 DEG C.The method of the present invention is to coolant-temperature gage
Do not specially require, as long as the water of liquid can, and the reaction of water temperature height can be fast, therefore water temperature is controlled at 10~100 DEG C
Under can keep fast hydrogen making, meet the requirement of hydrogen production efficiency.
Preferably, the addition speed of above-mentioned hydrogen production process, water is at the uniform velocity.It is deposited between rate and outle water rate that hydrogen generates
In proportional relation, there is no limit can determine water inlet to the rate size of water inlet according to demand of the practical application to amounts of hydrogen
Rate.It is uniformly critically important in the application to control hydrogen gas rate, the continual and steady power supply that can ensure hydrogen fuel cell.
Preferably, water is added into composite hydrolysis hydrogen manufacturing material using peristaltic pump or syringe pump in above-mentioned hydrogen production process.It is theoretical
On, being added if 1mL water is fully converted into hydrogen has 1.24L, even so need the hydrogen flowing quantity of 1000L/min, supplies water
Amount, can meet demand with the pump of a very little also less than 1L/min.Syringe pump and peristaltic pump be two kinds can be more accurate
The device of control plus water speed rate.
Heretofore described system quality is whole hydrogen manufacturing materials including water.
Compared with prior art, the invention has the advantages that:
(1) the present invention provides a kind of portable hydrogen scheme of high power capacity (hydrogen manufacturing material, methods).Although utilizing
NaBH4Hydrolysis hydrogen manufacturing research it is very much, but traditional utilize NaBH4The method of solution is difficult to realize higher practical storage
Hydrogen capacity converts, and usual quality hydrogen content is all below 2%.And in the present invention, utilize P2O5Activate NaBH4, in the material of optimization
May be implemented under proportioning be more than 5% quality hydrogen output.The present invention is to realizing that Portable in-situ hydrogen manufacturing is of great significance.
(2) in traditional NaBH4In hydrogen production reaction, need using transition-metal catalysts and NaBH such as Co, Ni, Pt4Solution
Contact catalysis NaBH4Hydrogen release, and in the present invention only need use cheap P2O5, it is not necessarily to any transition metal, advantageously reduces material
Expect cost, while heavy metal free pollute, product be borate and phosphate, it is more friendly to environment.
(3) present invention replaces NaBH with solid reactant4Solution, reactant in addition to water is solid, easy to carry.
(4) the hydrogen manufacturing system 200 DEG C or less will not automatic hydrogen release, can be stored with long-term safety.