阅读说明：本技术 单原子熔融盐催化剂及其制备方法和聚光太阳能催化反应系统 (Monoatomic molten salt catalyst, preparation method thereof and concentrating solar catalytic reaction system ) 是由 李长明 汪昌红 于 2020-05-13 设计创作，主要内容包括：本发明公开了一种单原子熔融盐催化剂制备方法,将过渡金属供给体与碱金属碳酸盐和/或碱土金属碳酸盐均匀混合后,加热至碱金属碳酸盐和/或碱土金属碳酸盐的熔点以上,使碱金属碳酸盐和/或碱土金属碳酸盐形成均一的熔融盐,过渡金属以单原子的形式分散于熔融盐中,得到单原子熔融盐催化剂。利用熔融盐作为过渡金属单原子催化剂的载体,能够实现过渡金属单原子催化剂的均匀分布,使催化剂的活性反应面充分暴露,提高催化剂的催化效率。本发明还公开了一种聚光太阳能催化反应系统,将二氧化碳和水反应合成氢气和一氧化碳,从而实现将太阳能转化为成易于储存和运输的化学燃料,并实现温室气体的循环利用,将对未来能源转换具有重要意义。(The invention discloses a preparation method of a monatomic molten salt catalyst, which comprises the steps of uniformly mixing a transition metal donor with alkali metal carbonate and/or alkaline earth metal carbonate, heating the mixture to a temperature higher than the melting point of the alkali metal carbonate and/or the alkaline earth metal carbonate to enable the alkali metal carbonate and/or the alkaline earth metal carbonate to form uniform molten salt, and dispersing the transition metal in the molten salt in a monatomic form to obtain the monatomic molten salt catalyst. The molten salt is used as a carrier of the transition metal monatomic catalyst, so that the transition metal monatomic catalyst can be uniformly distributed, the active reaction surface of the catalyst is fully exposed, and the catalytic efficiency of the catalyst is improved. The invention also discloses a concentrating solar catalytic reaction system, which is used for synthesizing hydrogen and carbon monoxide by reacting carbon dioxide and water, so that solar energy is converted into chemical fuel which is easy to store and transport, the recycling of greenhouse gas is realized, and the concentrating solar catalytic reaction system has important significance for future energy conversion.)

1. A method for preparing a monatomic molten salt catalyst is characterized by comprising the following steps:

uniformly mixing a transition metal donor and alkali metal carbonate and/or alkaline earth metal carbonate, heating to a temperature higher than the melting point of the alkali metal carbonate and/or alkaline earth metal carbonate to form uniform molten salt of the alkali metal carbonate and/or alkaline earth metal carbonate, and dispersing the transition metal in the molten salt in a monoatomic form to obtain the monoatomic molten salt catalyst.

2. The method for producing a monatomic molten salt catalyst according to claim 1, characterized in that: the alkali metal carbonate includes, but is not limited to, lithium carbonate (Li)₂CO₃) Sodium carbonate (Na)₂CO₃) And potassium carbonate (K)₂CO₃) Or a mixture of at least two thereof.

3. The method for producing a monatomic molten salt catalyst according to claim 1, characterized in that the monatomic molten salt catalyst is produced byIn the following steps: the alkaline earth metal carbonates include, but are not limited to, barium carbonate (BaCO)₃) And strontium carbonate (SrCO)₃) Or a mixture of at least two thereof.

4. The method for producing a monatomic molten salt catalyst according to claim 1, characterized in that: the transition metal donor includes, but is not limited to, one or a mixture of at least two of acetylacetone salt, carbonate, halide salt, and nitrate.

5. The method for producing a monatomic molten salt catalyst according to claim 4, characterized in that: the transition metal includes, but is not limited to, one or at least two of platinum (Pt), palladium (Pd), iron (Fe), zinc (Zn), chromium (Cr), molybdenum (Mo), cobalt (Co), copper (Cu), rhodium (Rh), and ruthenium (Ru).

6. The method for producing a monatomic molten salt catalyst according to claim 1, characterized in that: the transition metal includes platinum (Pt) and the transition metal donor includes a platinum donor including, but not limited to, one or a mixture of at least two of sodium chloroplatinate, potassium chloroplatinate, platinum tetrachloride, ammonium chloroplatinate, platinum nitrate, and platinum acetylacetonate.

7. The method for producing a monatomic molten salt catalyst according to any one of claims 1 to 6, characterized in that: in the monatomic molten salt catalyst, the mass ratio of the transition metal monatomic in the molten salt is 0.01% -10%.

8. A monatomic molten salt catalyst produced by the method for producing a monatomic molten salt catalyst according to any one of claims 1 to 7.

9. A concentrating solar catalytic reaction system is characterized in that: the solar energy collecting device comprises a catalytic reactor and a butterfly condenser for collecting solar energy to the catalytic reactor, wherein a light absorption layer for absorbing heat radiation covers the catalytic reactor, and a catalytic reaction chamber for storing the monatomic molten salt catalyst in the claim 8 is arranged in the catalytic reactor;

the gas inlet end of the catalytic reactor is provided with a reaction gas unit, and a gas storage tank for storing carbon dioxide (CO) is arranged in the reaction gas unit₂) And water vapor (H)₂O) gas chamber;

a gas separator is arranged at the gas outlet end of the catalytic reactor, two gas outlet channels are arranged on the gas separator, one gas outlet channel is connected with the reaction gas unit, and carbon dioxide (CO) obtained by separation is obtained₂) And water vapor (H)₂O) is introduced into the reaction gas unit, and a product collector is connected to the other gas outlet channel and used for storing hydrogen (H) separated by the gas separator₂) And carbon monoxide (CO).

10. The concentrating solar-catalyzed reaction system of claim 9, wherein: adjusting the angle of the butterfly condenser to change the condensing intensity, and controlling the catalytic reaction temperature of the catalytic reactor to be 300-1200 ℃.

Technical Field

The invention belongs to the technical field of light-gathering solar thermal catalysis chemical energy storage, and particularly relates to a transition metal monatomic catalyst dispersed in molten salt, a preparation method thereof, and a light-gathering solar catalytic reaction system which utilizes heat provided by solar thermal effect to efficiently convert carbon dioxide and water into hydrogen and carbon monoxide through the catalyst.

Background

Realizing the high-efficiency utilization of solar energy is also the key point for solving the energy problem in the future. Currently, the development and utilization of solar energy by human beings have the defects of low light collection efficiency, low energy conversion efficiency, high storage cost and the like. By using the concentrated solar technology, people can obtain the ideal high temperature through photo-thermal conversion. However, the conventional utilization is to generate hot steam by heat energy, and the hot steam drives a turbine engine to drive a generator to generate electricity. The mode has the advantages of multiple intermediate links, low energy conversion efficiency and timeliness and is not easy to store. The high-temperature catalytic generation of clean fuels such as hydrogen, carbon monoxide and the like through the concentrating solar technology has the advantages of zero emission, easiness in transportation, recyclability, renewability and the like, and also conforms to the future energy development trend. Designing an efficient and inexpensive thermal catalyst becomes a key point in achieving this approach.

The monatomic catalyst not only maximizes the utilization efficiency of each metal atom, but also exhibits unique catalytic activity. However, the existing monatomic catalysts are fixed on a specific substrate and the loading is relatively low. There is therefore a need to develop new thermal catalysts to address these problems.

Disclosure of Invention

In view of the above, the invention aims to provide a monatomic molten salt catalyst, a preparation method thereof and a concentrating solar catalytic reaction system, wherein molten salt is used as a carrier of a transition metal monatomic catalyst, so that the loading capacity can be increased, uniform distribution of the transition metal monatomic catalyst can be realized, the active reaction surface of the catalyst is fully exposed, and the catalytic efficiency of the catalyst is improved; the solar energy is converted into chemical fuel which is easy to store and transport, and the recycling of greenhouse gases is realized, so that the solar energy and greenhouse gas heat-preservation system has important significance for future energy conversion.

In order to achieve the purpose, the invention provides the following technical scheme:

the invention firstly provides a preparation method of a monatomic molten salt catalyst, which comprises the steps of uniformly mixing a transition metal donor and alkali metal carbonate and/or alkaline earth metal carbonate, heating the mixture to a temperature higher than the melting point of the alkali metal carbonate and/or the alkaline earth metal carbonate to enable the alkali metal carbonate and/or the alkaline earth metal carbonate to form uniform molten salt, and dispersing the transition metal in the molten salt in a monatomic form to obtain the monatomic molten salt catalyst.

Further, the alkali metal carbonate includes, but is not limited to, lithium carbonate (Li)₂CO₃) Sodium carbonate (Na)₂CO₃) And potassium carbonate (K)₂CO₃) Or a mixture of at least two thereof.

Further, the alkaline earth metal carbonates include, but are not limited to, barium carbonate (BaCO)₃) And strontium carbonate (SrCO)₃) Or a mixture of at least two thereof.

Further, the transition metal donor includes, but is not limited to, one or a mixture of at least two of acetylacetone salt, carbonate, halide salt, and nitrate.

Further, the transition metal includes one or at least two of platinum (Pt), palladium (Pd), iron (Fe), zinc (Zn), chromium (Cr), molybdenum (Mo), cobalt (Co), copper (Cu), rhodium (Rh), and ruthenium (Ru).

Further, the transition metal includes platinum (Pt), and the transition metal donor includes a platinum donor including, but not limited to, one or a mixture of at least two of sodium chloroplatinate, potassium chloroplatinate, platinum tetrachloride, ammonium chloroplatinate, platinum nitrate, and platinum acetylacetonate.

Further, in the monatomic molten salt catalyst, the mass ratio of the transition metal monatomic in the molten salt is 0.01% to 10%.

The invention also provides the monatomic molten salt catalyst prepared by the monatomic molten salt catalyst preparation method.

The invention also provides a concentrating solar catalytic reaction system, which comprises a catalytic reactor and a butterfly condenser for concentrating solar energy to the catalytic reactor, wherein a light absorption layer for absorbing heat radiation covers the catalytic reactor, and a catalytic reaction chamber for storing the monatomic molten salt catalyst is arranged in the catalytic reactor;

the gas inlet end of the catalytic reactor is provided with a reaction gas unit, and a gas storage tank for storing carbon dioxide (CO) is arranged in the reaction gas unit₂) And water vapor (H)₂O) gas chamber;

a gas separator is arranged at the gas outlet end of the catalytic reactor, two gas outlet channels are arranged on the gas separator, one gas outlet channel is connected with the reaction gas unit, and carbon dioxide (CO) obtained by separation is obtained₂) And water vapor (H)₂O) is introduced into the reaction gas unit, and a product collector is connected to the other gas outlet channel and used for storing hydrogen (H) separated by the gas separator₂) And carbon monoxide (CO).

Further, the angle of the butterfly condenser is adjusted to change the condensing intensity, and the catalytic reaction temperature of the catalytic reactor is controlled to be 300-1200 ℃.

The invention has the beneficial effects that:

according to the preparation method of the monatomic molten salt catalyst, the molten alkali metal carbonate and/or alkaline earth metal carbonate is used as the carrier of the transition metal monatomic catalyst, so that the loading capacity can be improved, the transition metal monatomic catalyst can be uniformly distributed, the active reaction surface of the catalyst is fully exposed, and the catalytic efficiency of the catalyst is improved; the alkali metal carbonate and/or alkaline earth metal carbonate which is molten at high temperature has stable properties, has low vapor pressure, low viscosity, high ion migration and diffusion speed, high heat capacity and heat transfer performance in a wide temperature range, has the capability of dissolving various materials, disperses transition metal with catalytic activity in molten salt in an atomic level, and directly takes the molten salt as a medium for catalytic reaction, thereby not only providing high-temperature reaction conditions, but also playing a catalytic role.

According to the concentrating solar catalytic reaction system, solar heat radiation is transferred to the catalytic reactor by utilizing the concentrating effect of the disc type condenser lens and then is converted into heat energy required by catalytic reaction, so that the high-efficiency conversion and utilization of renewable solar energy are realized; the method has the advantages of short process flow, simple operation and capability of realizing the technical purpose of large-scale production of the synthesis gas; carbon dioxide (CO) can be thermally catalyzed by using monatomic molten salt catalyst₂) And water vapor (H)₂O) to hydrogen (H)₂) And carbon monoxide (CO), convert solar energy into chemical fuel easy to store and transport, and realize the cyclic utilization of greenhouse gases, have important meaning to the future energy conversion.

Drawings

In order to make the object, technical scheme and beneficial effect of the invention more clear, the invention provides the following drawings for explanation:

FIG. 1 is a schematic structural diagram of an embodiment of a concentrating solar catalytic reaction system according to the present invention.

Description of reference numerals:

1-disc condenser, 2-reaction gas unit, 3-flowmeter, 4-catalytic reactor, 5-light absorption layer, 6-gas separator and 7-product collector.

Detailed Description

The present invention is further described with reference to the following drawings and specific examples so that those skilled in the art can better understand the present invention and can practice the present invention, but the examples are not intended to limit the present invention.

In the preparation method of the monatomic molten salt catalyst of the embodiment, a transition metal donor and an alkali metal carbonate and/or an alkaline earth metal carbonate are uniformly mixed and then placed in a high-temperature-resistant and corrosion-resistant container; the catalyst is heated to a temperature not lower than the melting point of the alkali metal carbonate and/or the alkaline earth metal carbonate to form a uniform molten salt of the alkali metal carbonate and/or the alkaline earth metal carbonate, and the transition metal is dispersed in the molten salt in the form of a monoatomic atom to obtain a monoatomic molten salt catalyst. In the monatomic molten salt catalyst of the present example, the mass ratio of the transition metal monatomic in the molten salt was 0.01% to 10%. This example provides uniform mixing of the transition metal donor and the alkali metal carbonate and/or alkaline earth metal carbonate after grinding in a mortar or ball mill.

Specifically, alkali metal carbonates include, but are not limited to, lithium carbonate (Li)₂CO₃) Sodium carbonate (Na)₂CO₃) And potassium carbonate (K)₂CO₃) Or a mixture of at least two thereof. Alkaline earth metal carbonates include, but are not limited to, barium carbonate (BaCO)₃) And strontium carbonate (SrCO)₃) Or a mixture of at least two thereof.

Further, the transition metal donor includes, but is not limited to, one or a mixture of at least two of acetylacetone salt, carbonate, halide salt, and nitrate. The transition metal includes one or at least two of platinum (Pt), palladium (Pd), iron (Fe), zinc (Zn), chromium (Cr), molybdenum (Mo), cobalt (Co), copper (Cu), rhodium (Rh) and ruthenium (Ru). And when the transition metal comprises platinum (Pt), the transition metal donor comprises a donor for platinum. Specifically, the donor such as platinum includes, but is not limited to, one or a mixture of at least two of sodium chloroplatinate, potassium chloroplatinate, platinum tetrachloride, ammonium chloroplatinate, platinum nitrate and platinum acetylacetonate.

In the preparation method of the monatomic molten salt catalyst, the molten alkali metal carbonate and/or alkaline earth metal carbonate is used as the carrier of the transition metal monatomic catalyst, so that the loading capacity can be improved, the transition metal monatomic catalyst can be uniformly distributed, the active reaction surface of the catalyst is fully exposed, and the catalytic efficiency of the catalyst is improved; the alkali metal carbonate and/or alkaline earth metal carbonate which is molten at high temperature has stable properties, has low vapor pressure, low viscosity, high ion migration and diffusion speed, high heat capacity and heat transfer performance in a wide temperature range, has the capability of dissolving various materials, disperses transition metal with catalytic activity in molten salt in an atomic level, and directly takes the molten salt as a medium for catalytic reaction, thereby not only providing high-temperature reaction conditions, but also playing a catalytic role.

Fig. 1 is a schematic structural diagram of an embodiment of the concentrating solar catalytic reaction system according to the present invention. The concentrating solar catalytic reaction system comprises a catalytic reactor 4 and a butterfly condenser 1 for concentrating solar energy to the catalytic reactor 4, wherein a light absorption layer 5 for absorbing heat radiation covers the catalytic reactor 4, and a catalytic reaction chamber for storing a monatomic molten salt catalyst is arranged in the catalytic reactor 4, namely the catalytic reaction chamber has the characteristics of high temperature resistance and corrosion resistance. The angle of the butterfly condenser of this embodiment is adjustable, and in the catalytic reaction process, the catalytic reaction temperature of the catalytic reactor 4 can be controlled to 300-.

The catalytic reactor 4 of the present embodiment has a reaction gas unit 2 at the gas inlet end, and carbon dioxide (CO) is stored in the reaction gas unit 2₂) And water vapor (H)₂O), the gas chamber is used for accommodating gas to be reacted and preheating and gasifying the gas to be reacted.

The gas outlet end of the catalytic reactor 4 of this embodiment is provided with a gas separator 6, the gas separator 6 is provided with two gas outlet channels, one of the gas outlet channels is connected with the reaction gas unit 2, and carbon dioxide (CO) obtained by separation is separated₂) And water vapor (H)₂O) into the reaction gas unit 2, i.e. uncatalyzed carbon dioxide (CO)₂) And water vapor (H)₂O) is introduced into the reaction gas unit 2 for recycling; the other gas outlet channel is connected with a product collector 7, and the product collector 7 is used for storing hydrogen (H) separated by the gas separator 6₂) And carbon monoxide (CO).

Preferably, a flow meter 3 for detecting the gas flow is arranged between the reaction gas unit 2 and the catalytic reactor 4, and is used for detecting the flow of the gas to be reacted in real time.

The concentrating solar catalytic reaction system of the embodiment utilizes a disc type condenserSolar heat radiation is transferred to the catalytic reactor by the light condensation effect and then is converted into heat energy required by catalytic reaction, so that the high-efficiency conversion and utilization of renewable solar energy are realized; the method has the advantages of short process flow, simple operation and capability of realizing the technical purpose of large-scale production of the synthesis gas; carbon dioxide (CO) can be thermally catalyzed by using monatomic molten salt catalyst₂) And water vapor (H)₂O) to hydrogen (H)₂) And carbon monoxide (CO), convert solar energy into chemical fuel easy to store and transport, and realize the cyclic utilization of greenhouse gases, have important meaning to the future energy conversion.

The concentrated solar catalytic reaction system of the present invention will be described in detail with reference to specific examples.

Example 1

With 100g of sodium carbonate (Na)₂CO₃) And 100g of potassium carbonate (K)₂CO₃) Molten salt with 10g of iron acetylacetonate as a catalytic reaction system and carbon dioxide (CO)₂) And water vapor (H)₂O) is used as reaction raw material gas, and the catalytic reactor 4 is made of sealable stainless steel. Firstly, sodium carbonate (Na)₂CO₃) Potassium carbonate (K)₂CO₃) Grinding and uniformly mixing the three salts with ferric acetylacetonate, placing the mixture in a catalytic reactor 4, heating to 900 ℃, and keeping the temperature for 3 hours; then the gas inlet end and the gas outlet end of the catalytic reactor 4 are connected, argon is firstly introduced to remove oxygen and other gases in the cavity, and then the reaction gas unit 2 and the gas separator 6 are connected to remove carbon dioxide (CO)₂) And water vapor (H)₂O) mixed gas of 1: 1 is introduced into a catalytic reactor 4 at a gas flow rate of 10mL/min for 12 hours, the temperature is kept constant during the reaction, and the gas after the reaction is collected to obtain a catalytic reaction product hydrogen (H)₂) And carbon monoxide (CO).

Example 2

With 100g of sodium carbonate (Na)₂CO₃) And 100g of potassium carbonate (K)₂CO₃) Molten salt with 10g of zinc acetylacetonate as catalytic reaction system and carbon dioxide (CO)₂) And water vapor (H)₂O) as reaction raw material gas, and the catalytic reactor 4 is made of sealable stainless steelAnd (4) quality. Firstly, sodium carbonate (Na)₂CO₃) Potassium carbonate (K)₂CO₃) Grinding and uniformly mixing the three salts with zinc acetylacetonate, placing the mixture in a catalytic reactor 4, heating to 900 ℃, and keeping the temperature for 3 hours; then the gas inlet end and the gas outlet end of the catalytic reactor 4 are connected, argon is introduced to remove oxygen and other gases in the cavity, and then the reaction gas unit 2 and the gas separator 6 are connected to remove carbon dioxide (CO)₂) And water vapor (H)₂O) mixed gas of 1: 1 is introduced into a catalytic reactor 4 at a gas flow rate of 10mL/min for 12min, the temperature is kept constant during the reaction, and the reacted gas is collected to obtain a catalytic reaction product hydrogen (H)₂) And carbon monoxide (CO).

The above-mentioned embodiments are merely preferred embodiments for fully illustrating the present invention, and the scope of the present invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention. The protection scope of the invention is subject to the claims.