Metal-acid electrolysis hydrogen production system and method

Abstract

The invention relates to the technical field of electrolytic hydrogen production, in particular to a metal-acid electrolytic hydrogen production system which comprises an anode chamber and a cathode chamber, an electrolyte of the anode chamber is an alkaline solution, an electrolyte of the cathode chamber is an acidic solution, the anode chamber and the cathode chamber are communicated through a cation exchange membrane for conducting cations, and the cation exchange membrane is communicated with the cathode chamber through a metal-acid composite membrane. And the anode metal in the anode chamber is connected with the cathode catalyst in the cathode chamber through an external circuit. The device automatically generates electricity and hydrogen, does not need an external power supply to provide electric energy, can save a large amount of electric energy, and reduces the hydrogen production cost.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electrolytic hydrogen production, and particularly relates to a metal-acid electrolytic hydrogen production system. BACKGROUND

[0002] Hydrogen energy has great development potential in the fields of industry, transportation and energy storage due to its clean and efficient characteristics.

[0003] Electrolytic cell technology is one of the key means for producing hydrogen, and is of great significance for promoting the large-scale application of hydrogen energy. Currently, the production of hydrogen by electrolysis of water mainly relies on two technical routes of proton exchange membrane (PEM) and alkaline (ALK). The PEM electrolytic cell has high hydrogen production efficiency, but its core components mainly rely on imports, resulting in high cost and being limited by the supply of key equipment in the development of large-scale new energy electrolytic water hydrogen production. The ALK electrolytic cell has mature technology and a completely domestic supply chain, but its energy efficiency is relatively low, usually about 60%, and the current density is low, resulting in large electrolytic cell volume, large land occupation, high energy consumption and slow response speed. Therefore, the application of the ALK electrolytic cell in the field of renewable energy coupled hydrogen production is limited. Therefore, it is of great significance to develop a new type of electrolytic water hydrogen production technology with high efficiency, low cost and fast response capability for promoting the large-scale development of the hydrogen energy industry. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a metal-acid electrolytic hydrogen production system which does not need an external power supply to provide electric energy and realizes hydrogen production.

[0005] To achieve the above-mentioned purpose, the following technical solutions are adopted in the present application:

[0006] The metal-acid electrolytic hydrogen production system comprises an anode chamber and a cathode chamber, the electrolyte in the anode chamber is an alkaline solution, the electrolyte in the cathode chamber is an acidic solution, the anode chamber and the cathode chamber are connected through a cation exchange membrane for conducting cations, and the anode metal in the anode chamber is connected with the cathode catalyst in the cathode chamber through an external circuit.

[0007] Preferably, the alkaline solution is potassium hydroxide, sodium hydroxide, lithium hydroxide, calcium hydroxide or barium hydroxide.

[0008] Preferably, the acidic solution is hydrochloric acid, acetic acid, nitric acid, sulfuric acid or carbonic acid.

[0009] Preferably, the anode metal is potassium, calcium, sodium, magnesium, aluminum, zinc, iron or lead.

[0010] Preferably, the cathode catalyst is a foam metal catalyst, a carbon-based substrate composite material, a noble metal and its alloy, a non-noble metal catalyst or a non-metal catalyst.

[0011] Preferably, the cation exchange membrane is a sulfonic acid-based ion exchange membrane, a phosphoric acid-based ion exchange membrane or a high molecular polymer ion exchange membrane.

[0012] A hydrogen production method of a metal-acid electrolysis hydrogen production system, metal ions generated by an anode metal in an anode chamber enter an alkaline solution, cations in the alkaline solution enter an acidic solution in a cathode chamber through a cation exchange membrane, at the same time, the anode metal in the anode chamber loses electrons and provides current to a cathode catalyst through an external circuit, and the acidic solution in the cathode chamber produces hydrogen gas on the cathode catalyst.

[0013] Preferably, the alkaline solution is continuously injected into the anode chamber to maintain pH>7.

[0014] Preferably, the acidic solution is continuously injected into the cathode chamber to maintain pH<7.

[0015] Compared with the prior art, the beneficial effects of the present application are:

[0016] 1. The metal-acid electrolysis hydrogen production system of the present application combines the advantages of PEM electrolysis cells and ALK electrolysis cells, has high hydrogen ion concentration, fast reaction rate, and no gas mixture is generated.

[0017] 2. The present application produces hydrogen spontaneously without the need for an external power supply to provide electrical energy, which can save a large amount of electrical energy and reduce the cost of hydrogen production.

[0018] 3. The acidic solution electrolyte contains more H + ions, and the acidic electrolyte as a carrier for HER is more conducive to the occurrence of catalyst HER reaction.

[0019] 4. The ion exchange membrane separates the negative electrode chamber and the positive electrode chamber of the battery, the gas purity is high (more than 90%), no further purification treatment is needed, the system process is simplified, and the electrolysis cell reaction efficiency is improved.

[0020] 5. The present application has the advantages of high efficiency, high performance, fast response speed and saving electrical energy. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The present application is a metal-acid electrolysis hydrogen production system structure diagram.

[0022] Figure 2 The present application is a metal-acid electrolysis hydrogen production system structure diagram.

[0023] Figure 3 The present application is an electrolysis performance curve of Example 1.

[0024] Figure 4 The present application is a metal-acid electrolysis hydrogen production system structure diagram.

[0025] Figure 5 Electrolysis performance graph for Example 2. DETAILED DESCRIPTION

[0026] In the description of the present application, it is to be understood that the orientations or positional relationships indicated by the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" and the like are only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" and the like can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0027] Unless otherwise expressly specified and limited, the terms "mounting", "connecting", "connection" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0028] As Figure 1 A metal-acid electrolysis hydrogen production system, comprising an anode chamber, a cathode chamber, the electrolyte in the anode chamber is an alkaline solution, the electrolyte in the cathode chamber is an acidic solution, the anode chamber and the cathode chamber are connected through a cation exchange membrane for conducting cations, and the anode metal in the anode chamber is connected with the cathode catalyst in the cathode chamber through an external circuit.

[0029] The alkaline solution is potassium hydroxide, sodium hydroxide, lithium hydroxide, calcium hydroxide or barium hydroxide.

[0030] The acidic solution is hydrochloric acid, acetic acid, nitric acid, sulfuric acid or carbonic acid.

[0031] The anode metal is a active metal, including potassium, calcium, sodium, magnesium, aluminum, zinc, iron or lead.

[0032] The cathode catalyst is a foam metal catalyst, a carbon substrate composite material, a noble metal and its alloy, a non-noble metal catalyst or a non-metal catalyst.

[0033] The foamed metal catalyst includes foamed nickel, foamed titanium or foamed titanium loaded with Pt.

[0034] The carbon substrate composite material is Pt / C.

[0035] The noble metal and its alloy include foamed titanium loaded with Pt, titanium mesh loaded with Pt, Pt / C, Ru-based catalyst or Ir-based catalyst.

[0036] The non-noble metal includes Fe-based catalyst or Co-based catalyst.

[0037] The cation exchange membrane is a sulfonic acid-based ion exchange membrane, a phosphoric acid-based ion exchange membrane or a high polymer ion exchange membrane.

[0038] The sulfonic acid-based ion exchange membrane is a perfluorosulfonic acid diaphragm Nafion membrane (Nafion 115, Nafion 117, Nafion 212).

[0039] The phosphoric acid-based ion exchange membrane is a polybenzimidazole ion exchange membrane.

[0040] The high polymer ion exchange membrane includes an ethylene pyrrolidone ion exchange membrane, a polyvinylidene fluoride ion exchange membrane or a polytetrafluoroethylene ion exchange membrane.

[0041] A hydrogen production method of a metal-acid electrolysis hydrogen production system, metal ions generated by an anode metal in an anode chamber enter an alkaline solution, cations in the alkaline solution enter an acidic solution in a cathode chamber through a cation exchange membrane, at the same time, the anode metal in the anode chamber loses electrons and provides current to a cathode catalyst through an external circuit, the acidic solution in the cathode chamber generates hydrogen gas on the cathode catalyst, the cathode chamber continuously generates corresponding salt, and after saturation, corresponding acid hydrogen salt precipitates are precipitated.

[0042] The alkaline solution is continuously injected into the anode chamber to maintain pH>7.

[0043] The acidic solution is continuously injected into the cathode chamber to maintain pH<7.

[0044] The preferred embodiments of the present application are described in detail above, but the present application is not limited to the specific details in the above-described embodiments, and various simple modifications can be made to the technical solutions of the present application within the technical concept of the present application, and these simple modifications all belong to the protection scope of the present application. In addition, it should be noted that, in the case where there is no contradiction, each specific technical feature described in the above-described specific embodiments can be combined in any appropriate manner, and in order to avoid unnecessary repetition, the present application will not make any further description on various possible combination manners. In addition, various different embodiments of the present application can also be combined in any manner, as long as it does not deviate from the technical concept of the present application, and it should also be considered as the disclosed content of the present application.

[0045] In order to make the object, technical solutions and technical effects of the present application clearer, the technical solutions in the embodiments of the present application are described clearly and completely. However, the embodiments described below are only some of the embodiments of the present application, not all the embodiments. All other embodiments obtained by those skilled in the art on the basis of the embodiments in the present application without creative labor shall fall within the protection scope of the present application.

[0046] Embodiment 1

[0047] As shown in Figure 2 , a metal-acid electrolysis hydrogen production system includes an anode chamber, a cathode chamber, the anode metal is zinc, the cathode catalyst is Pt loaded on carbon paper, the anode metal in the anode chamber is connected with the cathode catalyst in the cathode chamber through an external circuit, the electrolyte in the anode chamber is a potassium hydroxide solution KOH with a molar concentration of 4 mol / L, the electrolyte in the cathode chamber is hydrochloric acid with a molar concentration of 1 mol / L, the anode chamber and the cathode chamber are connected through a cation exchange membrane for conducting cations, and the cation exchange membrane uses a Nafion membrane.

[0048] The anode chamber is continuously injected with an alkaline solution to maintain pH>7. The cathode chamber is continuously injected with an acidic solution to maintain pH<7. The Zn loses electrons on the anode side, and Zn ions are generated at the same time; the HER reaction occurs on the cathode side to generate H2, Cl - ions are generated; K + ions generated by the anode pass through the cation exchange membrane to the cathode side and combine with Cl - ions to generate KCl.

[0049] The external circuit is connected with an electrochemical workstation, and an electrolysis performance curve graph (as shown in Figure 3 ) is obtained by detection, and the maximum power density at room temperature is 50 mW / cm 2 .

[0050] Embodiment 2

[0051] As shown in Figure 4As shown, a metal-acid electrolysis hydrogen production system includes an anode chamber, a cathode chamber, the anode is aluminum metal, and the cathode is a carbon paper loaded with Pt. The anode metal in the anode chamber is connected to the cathode catalyst in the cathode chamber through an external circuit, the electrolyte in the anode chamber is a 4 mol / L KOH solution, and the electrolyte in the cathode chamber is 1 mol / L HCl. The anode chamber and the cathode chamber are connected through a cation exchange membrane for conducting cations, and the cation exchange membrane is a Nafion membrane. The anode chamber is continuously injected with an alkaline solution to maintain a pH>7. The cathode chamber is continuously injected with an acidic solution to maintain a pH<7.

[0052] The external circuit is connected to an electrochemical workstation, and the electrolysis performance curve is obtained by detection (as shown in Figure 5 The maximum power density at room temperature is 60 mW / cm 2 .

[0053] Although the embodiments of the present application have been shown and described, it is to be understood that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A metal-acid electrolysis hydrogen generation system, characterized by, The anode chamber, the cathode chamber, the electrolyte of the anode chamber is alkaline solution, the electrolyte of the cathode chamber is acid solution, the anode chamber and the cathode chamber are communicated through the cation exchange membrane for conducting cation, the anode metal in the anode chamber is connected with the cathode catalyst in the cathode chamber through the external circuit.

2. The metal-acid electrolysis hydrogen generation system of claim 1, wherein, The alkaline solution is potassium hydroxide, sodium hydroxide, lithium hydroxide, calcium hydroxide or barium hydroxide.

3. The metal-acid electrolysis hydrogen generation system of claim 1, wherein, The acid solution is hydrochloric acid, acetic acid, nitric acid, sulfuric acid or carbonic acid.

4. The metal-acid electrolysis hydrogen generation system of claim 1, wherein, The anode metal is potassium, calcium, sodium, magnesium, aluminum, zinc, iron or lead.

5. The metal-acid electrolysis hydrogen generation system of claim 1, wherein, The cathode catalyst is foam metal catalyst, carbon base composite material, noble metal and its alloy, non-noble metal catalyst or non-metal catalyst.

6. The metal-acid electrolysis hydrogen generation system of claim 1, wherein, The cation exchange membrane is sulfonic acid ion exchange membrane, phosphoric acid ion exchange membrane or high molecular polymer ion exchange membrane.

7. A method of producing hydrogen by a metal-acid electrolysis hydrogen production system, characterized by, The metal ion produced by the anode metal in the anode chamber enters the alkaline solution, the cation in the alkaline solution enters the acid solution in the cathode chamber through the cation exchange membrane, at the same time, the anode metal in the anode chamber loses electron and provides current for the cathode catalyst through the external circuit, and the acid solution in the cathode chamber produces hydrogen gas on the cathode catalyst.

8. The method of claim 1, wherein the metal-acid electrolysis system is a system according to any one of claims 2 to 7. The alkaline solution is continuously injected into the anode chamber to keep pH>7.

9. The method of claim 1, wherein the metal-acid electrolysis system is a system according to any one of claims 2 to 8. The acid solution is continuously injected into the cathode chamber to keep pH<7.

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