阅读说明：本技术 一种用于制备氢气的Al合金及其制备方法和应用 (Al alloy for preparing hydrogen and preparation method and application thereof ) 是由 张建斌 石玗 容煜 陆雨 焦凯 于 2020-07-03 设计创作，主要内容包括：本发明公开了一种用于制备氢气的Al合金及其制备方法和应用,涉及Al合金制氢技术领域,所述Al合金包括金属Al、Mg、Ga和Sn；其中,Sn的含量为0.6-1.2 wt.%,Mg的含量为0.41-1.7 wt.%,Ga的含量为0.2-2 wt.%,余量为Al；另外,还可以在上述Al合金中加入0.2-1.0 wt.%的Cu来改善铝合金的制氢性能。本发明的铝合金不仅降低了制氢铝合金的生产成本,而且提升了其制氢性能,使用本发明的铝合金在30℃、50℃、70℃、90℃下的产氢量分别为927.4 mL/g、1040.0mL/g、1143.5 mL/g、1247.0 mL/g。(The invention discloses an Al alloy for preparing hydrogen and a preparation method and application thereof, and relates to the technical field of hydrogen production of Al alloys, wherein the Al alloy comprises metal Al, Mg, Ga and Sn; wherein the content of Sn is 0.6-1.2wt.%, the content of Mg is 0.41-1.7wt.%, the content of Ga is 0.2-2wt.%, and the balance is Al; in addition, 0.2-1.0wt.% of Cu can be added into the Al alloy to improve the hydrogen production performance of the aluminum alloy. The aluminum alloy of the invention not only reduces the production cost of the aluminum alloy for hydrogen production, but also improves the hydrogen production performance, and the hydrogen production capacity of the aluminum alloy at 30 ℃, 50 ℃, 70 ℃ and 90 ℃ is 927.4 mL/g, 1040.0mL/g, 1143.5mL/g and 1247.0 mL/g respectively.)

1. An Al alloy for the production of hydrogen, characterized in that the Al alloy comprises the metals Al, Mg, Ga and Sn;

wherein the content of Sn is 0.6-1.2wt.%, the content of Mg is 0.41-1.7wt.%, the content of Ga is 0.2-2wt.%, and the balance is Al.

2. Al alloy for the production of hydrogen according to claim 1, characterized in that it comprises the metals Al, Mg, Ga and Sn;

wherein the content of Sn is 1.2wt.%, the content of Mg is 1.7wt.%, the content of Ga is 1.5wt.%, and the balance is Al.

3. An Al alloy for the production of hydrogen, characterized in that it consists of the metals Al, Mg, Ga, Sn and Cu;

wherein the content of Sn is 0.6-1.2wt.%, the content of Mg is 0.41-1.7wt.%, the content of Ga is 0.2-2wt.%, the content of Cu is 0.2-1.0wt.%, and the balance is Al.

4. Al alloy for the production of hydrogen according to claim 3, characterized in that it consists of the metals Al, Mg, Ga, Sn and Cu;

wherein the content of Sn is 1.2wt.%, the content of Mg is 1.7wt.%, the content of Ga is 1.5wt.%, the content of Cu is 0.8wt.%, and the balance is Al.

5. A method of producing the Al alloy according to any one of claims 1 to 4, characterized in that the method comprises the steps of:

s1: weighing metal raw materials according to the component ratio;

s2: putting the weighed Al into a graphite crucible and transferring the graphite crucible into a box-type resistance furnace, keeping the temperature of the resistance furnace at 720-780 ℃, keeping the temperature for 5-6min after the Al is completely melted into a liquid state, taking out and adding other metal raw materials, stirring the mixture after all the metals are completely dissolved to uniformly mix the metals, then putting the mixture into the resistance furnace, heating the mixture to 630-680 ℃, adding 0.2-0.8wt.% of refining agent hexachloroethane for refining, continuously stirring the mixture in the refining process, and removing slag;

s3: pouring the alloy solution in the S2 into a mould after slagging-off is finished;

s4: after cooling, the samples were removed from the molds and numbered.

6. The use of the Al alloy according to any one of claims 1 to 4 in a fuel cell, wherein a hydrogen gas is produced by hydrolysis of the Al alloy as a hydrogen source for the fuel cell.

Technical Field

The invention relates to the technical field of hydrogen production by using Al alloy, in particular to Al alloy for preparing hydrogen and a preparation method and application thereof.

Background

Fuel Cells (FC) are driven by pure, clean hydrogen gas, rather than being obtained by fossil fuel reformulation, and thus do not contaminate the surrounding environment. Although FC is used in the field of new energy electric vehicles on a small scale nowadays, FC has some engineering technical difficulties and lacks a reliable and efficient hydrogen supply system, so that FC cannot be popularized on a large scale. In the aspect of hydrogen production, at present, hydrogen production by fossil fuel, hydrogen production by biomass gasification, hydrogen production by water electrolysis, hydrogen production by photocatalysis, non-mineral energetic materials and the like are mainly used.

The traditional hydrogen production technology has the problems of cost, transportation, storage and the like. In practical application, the hydrogen production from fossil resources is most widely applied, however, the fossil resources are non-renewable resources, and the purity of hydrogen in the product is not high; the hydrogen production by water electrolysis needs continuous electric energy, and the energy conversion rate is low, and the safety is not high enough; although biomass hydrogen production is cleaner and easy to transport, the biomass hydrogen production has the natural defect of high energy consumption, the process flow is also more complex, the reaction is difficult to control, and a large amount of byproducts exist. Although the above hydrogen production technology is suitable for large-scale production, the demand of fuel cells for high-purity and safe hydrogen sources cannot be met.

With the continuous and intensive research, researchers find that metals and their compounds can generate a large amount of high-purity hydrogen under certain conditions, and that the metals do not have the problems of transportation safety (such as explosion, leakage, evaporation) and the like. At present, the metal hydrogen production mainly adopts Al-based alloy to produce hydrogen, because Al is the most abundant metal element in the earth crust, exists in the form of ore in nature, is easy to prepare and has price advantage, and has no harsh storage condition; but because the compact oxide film exists on the surface of the Al, the further reaction of the Al and water is hindered, in order to solve the problem, one method is to destroy the compact oxide film on the surface of the Al by traditional mechanical means such as grinding, ball milling and the like, and simultaneously change the specific surface area of the Al and the aluminum alloy to make the Al and the aluminum alloy powder, thereby improving the contact area of the reaction; however, the ball milling cost is high, and the specific surface area and the surface energy of the aluminum powder are high, so that the chemical property is active, and safety accidents are easy to happen, so that the storage (easy oxidation) and transportation of the Al powder limit the application of the aluminum powder in hydrogen production; the other method is to add Ga, Sn, In and other metals into aluminum to form low-melting-point activated aluminum alloy so as to reduce the activation energy of the reaction; and part of low-melting point metal destroys Al grain boundaries to improve the hydrogen production performance of Al, but Ga, Sn and In all belong to rare and precious metals, so that the hydrogen production cost is greatly increased.

Disclosure of Invention

In order to solve the problems, the invention provides an Al alloy for preparing hydrogen and a preparation method and application thereof, and the method improves the hydrogen production amount and the hydrogen production rate of the Al alloy by adding a small amount of Ga, Sn, Mg, Cu and other elements into Al, and has the advantages of small addition amount and low cost.

In order to achieve the purpose, one of the technical schemes adopted by the invention is as follows: an Al alloy for producing hydrogen, the Al alloy comprising the metals Al, Mg, Ga and Sn;

wherein the content of Sn is 0.6-1.2wt.%, the content of Mg is 0.41-1.7wt.%, the content of Ga is 0.2-2wt.%, and the balance is Al.

Further, the Al alloy includes metals Al, Mg, Ga, and Sn;

wherein the content of Sn is 1.2wt.%, the content of Mg is 1.7wt.%, the content of Ga is 1.5wt.%, and the balance is Al.

The second technical scheme adopted by the invention is as follows: an Al alloy for the production of hydrogen, consisting of the metals Al, Mg, Ga, Sn and Cu;

wherein the content of Sn is 0.6-1.2wt.%, the content of Mg is 0.41-1.7wt.%, the content of Ga is 0.2-2wt.%, the content of Cu is 0.2-1.0wt.%, and the balance is Al.

Further, the Al alloy is composed of metals Al, Mg, Ga, Sn, and Cu;

wherein the content of Sn is 1.2wt.%, the content of Mg is 1.7wt.%, the content of Ga is 1.5wt.%, the content of Cu is 0.8wt.%, and the balance is Al.

The third technical scheme adopted by the invention is as follows: the preparation method of the Al alloy in any one of the above technical schemes comprises the following steps:

s1: weighing metal raw materials according to the component ratio;

s2: putting the weighed Al into a graphite crucible and transferring the graphite crucible into a box-type resistance furnace, wherein the temperature of the resistance furnace is 720-780 ℃, keeping the temperature for 5-6min after the Al is completely melted into a liquid state, taking out and adding other metal raw materials, and stirring the mixture to uniformly mix the metal raw materials after all the metal is completely dissolved. Then putting the mixture into a resistance furnace, heating the mixture to 630-680 ℃, adding 0.2-0.8wt.% of refining agent hexachloroethane to refine the mixture, and continuously stirring the mixture in the refining process to remove slag;

s3: pouring the alloy solution in the S2 into a mould after slagging-off is finished;

s4: after cooling, the samples were removed from the molds and numbered.

The fourth technical scheme adopted by the invention is as follows: the application of the Al alloy in the fuel cell according to any of the above technical solutions, wherein hydrogen is prepared by hydrolysis reaction of the Al alloy as a hydrogen source of the fuel cell.

The invention has the beneficial effects that:

according to the invention, low-melting-point metals Ga, Sn and Mg are added into aluminum to form the low-melting-point activated aluminum alloy, low-cost Mg is used for replacing high-price In, the using amounts of Sn and Ga are reduced, although the hydrogen production amount is slightly reduced, the production cost of the Al alloy is greatly reduced, and after a large number of experimental researches are carried out on the optimization of Al alloy components, the content of Sn In the Al alloy is 1.2wt.%, the content of Mg is 1.7wt.%, and the content of Ga is 1.5wt.%, the hydrogen production amount can reach 833.7mL/g at 30 ℃, and can reach 1102.1mL/g at 90 ℃.

In order to further reduce the production cost of the hydrogen-producing aluminum alloy and improve the hydrogen-producing performance of the aluminum alloy, the aluminum alloy is further added with Cu, so that the aluminum alloy reaches 99.3 percent at 90 ℃. Further, the hydrogen production amounts at 30 ℃, 50 ℃, 70 ℃ and 90 ℃ were 927.4 mL/g, 1040.0mL/g, 1143.5mL/g and 1247.0 mL/g, respectively.

In addition, the aluminum alloy block is prepared by smelting and casting, so that the safe transportation of the aluminum alloy is facilitated.

In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention.

FIG. 1 is a graph showing the amount of hydrogen produced at 30 ℃ for Al alloys of examples 1 to 5 of the present invention;

FIG. 2 is a graph showing the amount of hydrogen produced at 90 ℃ for the Al alloys of examples 1 to 5 of the present invention;

FIG. 3 is an X-ray diffraction pattern of the Al alloy of examples 6 to 10 of the present invention;

FIG. 4 is a back-scattered scanning electron microscopy (BSEM) image of an Al alloy of examples 6-10 of the present invention;

FIG. 5 is a graph showing the amount of hydrogen produced at 30 ℃ for the Al alloys of examples 6 to 10 of the present invention;

FIG. 6 is a graph showing the amount of hydrogen produced at 90 ℃ for the Al alloys of examples 6 to 10 of the present invention;

FIG. 7 is a graph showing the hydrogen production conversion ratios of Al alloys of examples 6 to 10 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.