Low-temperature liquid-phase organic liquid hydrogen storage dehydrogenation catalyst and preparation process thereof

Abstract

The invention relates to the technical field of organic liquid hydrogen storage, in particular to a low-temperature liquid-phase organic liquid hydrogen storage dehydrogenation catalyst and a preparation process thereof.The low-temperature liquid-phase organic liquid hydrogen storage dehydrogenation catalyst comprises a carrier and an active component loaded on the carrier, and the carrier comprises one or more of a metal oxide, a molecular sieve and a two-dimensional porous material; the active component comprises one or more of silver, copper, nickel, molybdenum, platinum, cobalt and palladium, and the metal oxide comprises one or more of aluminum oxide, tin oxide, cerium oxide, titanium oxide and silicon oxide. The low-temperature liquid-phase organic liquid hydrogen storage dehydrogenation catalyst has the advantages that the low-temperature liquid-phase organic liquid hydrogen storage dehydrogenation catalyst is prepared by adding low-price non-noble metals such as silver, copper and nickel to the active components, so that the content of noble metal Pt used in the catalyst is reduced, and the cost required for preparing the low-temperature liquid-phase organic liquid hydrogen storage dehydrogenation catalyst is low; therefore, the dehydrogenation cost is reduced, and the low-temperature liquid-phase organic liquid hydrogen storage dehydrogenation catalyst is convenient to popularize.

Description

Technical Field

[0001] The invention relates to the technical field of organic liquid hydrogen storage, and in particular to a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst and a preparation process thereof. Background Art

[0002] The principle of liquid organic hydrogen storage technology (LOHC for short) is to achieve hydrogen storage (chemical bonding) by means of the reversible reaction and hydrogenation reaction of unsaturated liquid organic matter such as olefins, alkynes or aromatic hydrocarbons and hydrogen, and to achieve hydrogen release by means of dehydrogenation reaction. The mass hydrogen storage density is 5%-10%, and the hydrogen storage capacity is large. The hydrogen storage material is liquid organic matter, which can be transported at room temperature and pressure, which is convenient and safe. Low-temperature liquid hydrogen storage first compresses hydrogen, cools it before passing through the throttle valve, and produces a mixed liquid after undergoing Joule-Thomson isenthalpic expansion. After separating the liquid, the above cycle is continued to obtain high-purity liquid hydrogen. In the process of hydrogenation and dehydrogenation of low-temperature liquid organic liquid hydrogen storage, the catalyst can not only reduce the reaction temperature, but also improve the reaction rate of chemical hydrogen storage technology. The hydrogenation catalysts mainly include nickel catalysts, palladium and platinum catalysts, ruthenium catalysts and rhodium catalysts. Conventional hydrogenation catalysts are nickel metal catalysts with aluminum as the carrier, while for deep aromatic catalysis, precious metal catalysts are the first choice.

[0003] Among the precious metal catalysts, Pt-based catalysts are widely used in the dehydrogenation reaction process due to their excellent dehydrogenation performance. However, due to the high cost of the precious metal Pt, the dehydrogenation cost is high. Therefore, a low-temperature liquid phase organic liquid hydrogen storage dehydrogenation catalyst is needed to solve the problem of high cost. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the deficiencies in the prior art, the present invention provides a low-temperature liquid-phase organic liquid hydrogen storage and dehydrogenation catalyst and a preparation process thereof, which has the advantages of low cost and solves the problems in the prior art.

[0006] (II) Technical solution

[0007] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst, comprising a carrier and an active component loaded on the carrier, the carrier comprising one or more of metal oxides, molecular sieves and two-dimensional porous materials, and the active component comprising one or more of silver, copper, nickel, molybdenum, platinum, cobalt and palladium.

[0008] A preparation process of a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst, characterized in that it comprises the following steps:

[0009] Step 1) mixing the active component with the deionized water solution according to a proportion and stirring the mixture to ensure that the active component and the deionized water solution are fully mixed;

[0010] Step 2) immersing the carrier in a deionized water solution and stirring the solution to mix the carrier with the deionized water solution and the active component;

[0011] Step 3) mixing the carrier and the deionized water solution uniformly by using an ultrasonic cleaner;

[0012] Step 4) drying the mixed sample in a constant temperature vacuum drying oven;

[0013] Step 5) calcining the dried sample in a muffle furnace;

[0014] Step 6) performing a reduction reaction on the dried sample and cooling it to room temperature, thereby obtaining a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst.

[0015] Preferably, the instrument used for stirring in step 1 and step 2 is a constant temperature magnetic stirrer.

[0016] Preferably, in step 2, the active component is loaded on the carrier, the total loading amount of the active component on the carrier in step 2 is 0.1-5wt%, and the ratio of deionized water to the carrier in step 2 is 1-3:1.

[0017] Preferably, the drying temperature in step 4 is 60-70° C., and the drying time in step 4 is 5-7 hours.

[0018] Preferably, the calcination temperature in step 5 is 450-500° C., and the calcination time in step 5 is 6-9 hours.

[0019] Preferably, the reduction reaction in step 6 adopts a hydrogen-nitrogen mixed gas, the flow rate of the gas introduced into the reduction reaction is 75-100 L / min, the temperature adopted for dehydrogenation in step 6 is 180-250° C., and the gas pressure required for dehydrogenation in step 6 is 1 bar.

[0020] Preferably, the hydrogen storage material for the low-temperature liquid phase organic liquid hydrogen storage includes one of methylcyclohexane, ammonia borane, trans-decalin, ethylcarbazole, and carbazole.

[0021] (III) Beneficial effects

[0022] Compared with the prior art, the present invention provides a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst and a preparation process thereof, which has the following beneficial effects:

[0023] The low-temperature liquid-phase organic liquid hydrogen storage and dehydrogenation catalyst and its preparation process are prepared by adding relatively cheap non-precious metals such as silver, copper, and nickel to the active components to reduce the content of the precious metal Pt used in the catalyst, thereby reducing the cost required to prepare the low-temperature liquid-phase organic liquid hydrogen storage and dehydrogenation catalyst, thereby reducing the cost of dehydrogenation and facilitating the promotion of the low-temperature liquid-phase organic liquid hydrogen storage and dehydrogenation catalyst. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] A low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst comprises a carrier and an active component loaded on the carrier, wherein the carrier comprises one or more of metal oxides, molecular sieves and two-dimensional porous materials, and the active component comprises one or more of silver, copper, nickel, molybdenum, platinum, cobalt and palladium.

[0026] A preparation process of a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst, characterized in that it comprises the following steps:

[0027] Step 1) mixing the active component with the deionized water solution according to a proportion and stirring the mixture to ensure that the active component and the deionized water solution are fully mixed;

[0028] Step 2) immersing the carrier in a deionized water solution and stirring the solution to mix the carrier with the deionized water solution and the active component;

[0029] Step 3) mixing the carrier and the deionized water solution uniformly by using an ultrasonic cleaner;

[0030] Step 4) drying the mixed sample in a constant temperature vacuum drying oven;

[0031] Step 5) calcining the dried sample in a muffle furnace;

[0032] Step 6) performing a reduction reaction on the dried sample and cooling it to room temperature, thereby obtaining a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst.

[0033] The instrument used for stirring in step 1 and step 2 is a constant temperature magnetic stirrer, which can control the heating device at an accuracy level of 0.1°C, so that the temperature of the deionized water solution remains constant during the stirring process, avoiding the situation where the mixing effect is affected by temperature instability.

[0034] In step 2, the active component is loaded on the carrier. In step 2, the total loading amount of the active component on the carrier is 0.1-5wt%. The total loading amount of the active component on the carrier can be in five stages: 0.1-1wt%, 1-2wt%, 2-3wt%, 3-4wt% and 4-5wt%. In step 2, the ratio of deionized water to the carrier is 1-3:1, and the ratio of ionized water to the carrier can be specifically divided into 1:1, 1.5:1, 2:1, 2.5:1 and 3:1.

[0035] The drying temperature in step 4 is 60-70° C., and the drying time in step 4 is 5-7 hours. During the drying process, the drying temperature is kept at a relatively stable state.

[0036] The calcination temperature in step 5 is 450-500° C., and the calcination time in step 5 is 6-9 hours.

[0037] In step 6, a hydrogen-nitrogen mixed gas is used for the reduction reaction. The flow rate of the gas introduced into the reduction reaction is 75-100 L / min. The flow rate of the gas introduced into the reduction reaction may also be 75-85 L / min, 85-90 L / min, or 90-100 L / min. The temperature used for dehydrogenation in step 6 is 180-250° C. The gas pressure required for dehydrogenation in step 6 is 1 bar. When performing dehydrogenation, the hydrogen-nitrogen mixed gas needs to be added at a specific flow rate.

[0038] The hydrogen storage material for low-temperature liquid phase organic liquid hydrogen storage includes methylcyclohexane, ammonia borane, trans-decalin, ethylcarbazole, and one of carbazoles. When the loading amount of the active component is 0.68wt%, the conversion rate of methylcyclohexane is higher.

[0039] In summary, the low-temperature liquid-phase organic liquid hydrogen storage and dehydrogenation catalyst and its preparation process, by adding relatively cheap non-precious metals such as silver, copper, and nickel to the active components to produce the low-temperature liquid-phase organic liquid hydrogen storage and dehydrogenation catalyst, reduces the content of the precious metal Pt used in the catalyst, thereby making the cost required to produce the low-temperature liquid-phase organic liquid hydrogen storage and dehydrogenation catalyst less, thereby reducing the cost of dehydrogenation and facilitating the promotion of the low-temperature liquid-phase organic liquid hydrogen storage and dehydrogenation catalyst.

[0040] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise one" do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0041] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst, characterized in that: It includes a carrier and an active component loaded on the carrier, wherein the carrier includes one or more of metal oxides, molecular sieves and two-dimensional porous materials, the active components include one or more of silver, copper, nickel, molybdenum, platinum, cobalt and palladium, the metal oxide includes one or more of aluminum oxide, tin oxide, cerium oxide, titanium oxide and silicon oxide, and the two-dimensional porous material is one or more of graphene, carbon nitride and boron nitride.

2. The preparation process of a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst according to claim 1, characterized in that: The following steps are included: Step 1) mixing the active component with the deionized water solution according to a proportion and stirring the mixture to ensure that the active component and the deionized water solution are fully mixed; Step 2) immersing the carrier in a deionized water solution and stirring the solution to mix the carrier with the deionized water solution and the active component; Step 3) mixing the carrier and the deionized water solution uniformly by using an ultrasonic cleaner; Step 4) drying the mixed sample in a constant temperature vacuum drying oven; Step 5) calcining the dried sample in a muffle furnace; Step 6) performing a reduction reaction on the dried sample and cooling it to room temperature, thereby obtaining a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst.

3. The preparation process of a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst according to claim 2, characterized in that: The instrument used for stirring in step 1 and step 2 is a constant temperature magnetic stirrer.

4. The preparation process of a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst according to claim 3, characterized in that: In step 2, the active components are loaded on the carrier, the total loading amount of the active components on the carrier in step 2 is 0.1-5wt%, and the ratio of deionized water to the carrier in step 2 is 1-3:

1.

5. The preparation process of a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst according to claim 4, characterized in that: The drying temperature in step 4 is 60-70° C., and the drying time in step 4 is 5-7 hours.

6. The process for preparing a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst according to claim 5, characterized in that: The calcination temperature in step 5 is 450-500° C., and the calcination time in step 5 is 6-9 hours.

7. The process for preparing a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst according to claim 6, characterized in that: The reduction reaction in step 6 adopts a hydrogen-nitrogen mixed gas, the flow rate of the gas introduced into the reduction reaction is 75-100 L / min, the temperature adopted for dehydrogenation in step 6 is 180-250° C., and the gas pressure required for dehydrogenation in step 6 is 1 bar.

8. The process for preparing a low-temperature liquid phase organic liquid hydrogen storage and dehydrogenation catalyst according to claim 7, characterized in that: The hydrogen storage material for the low-temperature liquid phase organic liquid hydrogen storage includes one of methylcyclohexane, ammonia borane, trans-decalin, ethylcarbazole, and carbazole.