Pretreatment liquid, method for preparing and using the same, and method for pretreating and dehydrogenating hydrogen storage organic liquid

Abstract

The present application relates to the field of dehydrogenation catalyst, and discloses a pretreatment liquid, a preparation method and application thereof, a pretreatment method and a hydrogen storage organic liquid dehydrogenation method.The pretreatment liquid comprises: (a) a hydrogen storage organic liquid; (b) a heterocyclic compound; and (c) a mixture of non-fused ring aromatic hydrocarbon compounds and hydrogenation products thereof.The present application poisons and pretreats the dehydrogenation catalyst in the pretreatment liquid of the dehydrogenation catalyst, utilizes the competitive adsorption of different components and the synergistic effect between the components, can improve the selectivity to high active sites, and thus improves the activity of the poisoned catalyst while improving the stability of the catalyst.

Description

Technical Field

[0001] This invention relates to the field of dehydrogenation catalysis technology, specifically to a pretreatment liquid and its preparation method and application, and a pretreatment method and a method for dehydrogenating hydrogen-storing organic liquids. Background Technology

[0002] Cycloalkanes such as cyclohexane, methylcyclohexane, and decahydronaphthalene can be used for efficient hydrogen storage and transportation. The reaction of hydrogenating aromatics to produce cycloalkanes in hydrogen production facilities, followed by dehydrogenation of the cycloalkanes at gas stations, will facilitate the delivery of hydrogen to fuel cell vehicles. Cycloalkanes have a relatively high hydrogen storage capacity (6-8% by weight, 60-63 kg / m³ by volume). 3 This is an advantage. In addition to high storage capacity, the dehydrogenation reaction exhibits high selectivity for hydrogen and aromatics (condensable) on the dehydrogenation catalyst. Therefore, hydrogen transported using this method is free of any contaminants, including CO or CO2.

[0003] CN113184804A uses non-fused-ring aromatic hydrocarbons, unsaturated heterocyclic compounds, and at least one hydrogen storage component as the main components to obtain a liquid organic material with good hydrogen storage efficiency and reduced overall energy consumption and cost of the hydrogen addition / dehydrogenation system. However, this technology transforms it into a transportable liquid, and when it is used for dehydrogenation, there is still a problem that the activity of the dehydrogenation catalyst is significantly reduced after poisoning compared to before poisoning. Summary of the Invention

[0004] The purpose of this invention is to overcome the problem that the activity of dehydrogenation catalysts decreases significantly after poisoning compared to before poisoning, and to provide a dehydrogenation catalyst pretreatment liquid, its preparation method and application, and a method for dehydrogenation of hydrogen storage organic liquids. This dehydrogenation catalyst pretreatment liquid can improve the stability of the dehydrogenation catalyst while simultaneously increasing its activity after poisoning.

[0005] While existing dehydrogenation catalysts operate at relatively low dehydrogenation reaction temperatures, their activity, especially initial activity, is often excessively high. This leads to over-dehydrogenation of some hydrocarbons, resulting in carbon deposition and decreased catalyst stability. Therefore, pretreatment is necessary. This involves adding specific amounts of a poisoning agent to the reactants to poison the highly active sites on the catalyst, thereby reducing the possibility of carbon deposition. However, the applicant of this application has found that existing poisoning pretreatment methods lack selectivity for specific highly active sites, resulting in a significant decrease in catalyst activity after poisoning compared to before poisoning. Based on these reasons, this application proposes a pretreatment solution and method for hydrogen storage organic liquid dehydrogenation catalysts to address the problems encountered in the poisoning pretreatment of dehydrogenation catalysts.

[0006] To achieve the above objectives, the present invention provides a dehydrogenation catalyst pretreatment liquid comprising: (a) a hydrogen storage organic liquid; (b) a heterocyclic compound; and (c) a mixture of a non-fused-ring aromatic hydrocarbon compound and its hydrogenation products.

[0007] A second aspect of the present invention provides a method for preparing the dehydrogenation catalyst pretreatment liquid, the method comprising: S1 undergoing an incomplete hydrogenation reaction of a non-fused-ring aromatic hydrocarbon compound to obtain component (c); S2 mixing component (a), component (b) and component (c) to obtain the dehydrogenation catalyst pretreatment liquid.

[0008] A third aspect of the present invention provides the application of the dehydrogenation catalyst pretreatment liquid in the pretreatment of dehydrogenation catalysts.

[0009] The fourth aspect of the present invention provides the application of the dehydrogenation catalyst pretreatment liquid in a dehydrogenation catalyst for hydrogen storage organic liquids.

[0010] The fifth aspect of the present invention provides a method for pretreating a dehydrogenation catalyst, the method comprising: contacting the dehydrogenation catalyst pretreatment solution with the dehydrogenation catalyst under pretreatment conditions to pretreat, thereby obtaining a pretreated dehydrogenation catalyst.

[0011] The sixth aspect of the present invention provides a method for dehydrogenating a hydrogen storage organic liquid, the method comprising: (1) pretreating the dehydrogenation catalyst according to the pretreatment method of the dehydrogenation catalyst; and (2) reacting the hydrogen storage organic liquid with the pretreated dehydrogenation catalyst under dehydrogenation conditions.

[0012] Compared with the prior art, the present invention has at least the following beneficial effects:

[0013] This invention employs a dehydrogenation catalyst pretreatment solution to poison the dehydrogenation catalyst. By utilizing the competitive adsorption of different components and the synergistic effect between them, the selectivity for highly active sites can be improved, thereby enhancing both the activity and stability of the poisoned catalyst while simultaneously improving its stability. Detailed Implementation

[0014] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0015] The first aspect of this invention provides a dehydrogenation catalyst pretreatment solution, comprising:

[0016] (a) Hydrogen-storing organic liquid;

[0017] (b) Heterocyclic compounds;

[0018] (c) A mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products.

[0019] As mentioned above, when using dehydrogenation catalysts, a specific amount of a component that can poison the active components is often added to the feedstock to poison the high-activity sites of the catalyst, thereby reducing the possibility of carbon deposition. However, the activity of the poisoned catalyst is significantly lower than that before poisoning. According to the present invention, the dehydrogenation catalyst is pretreated with a dehydrogenation catalyst pretreatment solution for poisoning. By utilizing the competitive adsorption of different components and the synergistic effect between the components, the selectivity for high-activity sites can be improved, thereby improving the activity of the poisoned catalyst while improving the stability of the catalyst.

[0020] According to the present invention, in some embodiments, the pretreatment liquid comprises, by weight, (a) 90-98 parts of hydrogen-storing organic liquid, (b) 0.0001-0.005 parts of heterocyclic compound, and (c) 2-10 parts of a mixture of non-fused-ring aromatic hydrocarbon compound and its hydrogenation product.

[0021] According to some preferred embodiments of the present invention, the pretreatment solution comprises, by weight, (a) 92-95 parts of a hydrogen-storing organic liquid, (b) 0.0002-0.0015 parts of a heterocyclic compound, and (c) 5-8 parts of a mixture of a non-fused-ring aromatic hydrocarbon compound and its hydrogenation product. By employing the aforementioned embodiments, the adsorption competitiveness among the various components can be improved, and the synergistic effect between different components can enhance the selectivity of the feedstock for highly active sites.

[0022] According to the present invention, a heterocyclic compound refers to a compound whose ring-forming atoms include at least one heteroatom in addition to carbon atoms. The type of heteroatom is not limited as long as the purpose of the present invention is achieved. In some embodiments, the heteroatom in the heterocyclic compound includes one or more of N, S, P, and O. It is understood that if the heterocyclic compound contains multiple heteroatoms, the type of each heteroatom can be the same or different. Using the foregoing embodiments, a poisoning pretreatment of the dehydrogenation catalyst can be performed, reducing carbon deposition defects during the use of the dehydrogenation catalyst.

[0023] According to the present invention, in some embodiments, the heteroatom in the heterocyclic compound includes at least one N, such as one N, two N, three N, four N, preferably 1-3 N. By employing the aforementioned embodiments, the synergistic effect between the heterocyclic compound and the mixture of the non-fused-ring aromatic hydrocarbon compound and its hydrogenation product is improved, thereby enhancing the activity of the poisoned catalyst while simultaneously improving the stability of the dehydrogenation catalyst.

[0024] According to the present invention, in some embodiments, the total number of heteroatoms is 1-3, preferably 1-2. By employing the aforementioned embodiments, the poisoning and inactivation of highly dehydrogenation active sites of noble metal atoms can be reduced, thereby preventing excessive dehydrogenation and coking of the organic liquid hydrogen storage solution.

[0025] According to the present invention, in some embodiments, the heterocyclic compound has 1 to 5 cyclic structures, preferably 1 to 3, for example 1, 2 or 3.

[0026] According to the present invention, in some embodiments, the cyclic structure in the heterocyclic compound is at least a three-membered ring structure, preferably a 5-8 membered ring structure, such as a five-membered ring structure, a six-membered ring structure, a seven-membered ring structure, or an eight-membered ring structure.

[0027] According to the present invention, in some embodiments, the heterocyclic compound includes one or more of quinoline compounds, piperidine compounds, pyrrole compounds, imidazole compounds, pyrazine compounds, pyrimidine compounds, acridine compounds, thiophene compounds, furan compounds, and carbazole compounds; wherein, those skilled in the art will understand that X-class compounds include X compounds and compounds with substituents, for example, quinoline compounds include quinoline and quinoline with substituents.

[0028] According to the present invention, the advantages of the present invention are illustrated by example using compounds of class X, but the present invention is not limited thereto.

[0029] According to the present invention, in some preferred embodiments, the heterocyclic compound includes quinoline compounds and / or piperidine compounds. Using the foregoing embodiments, the selectivity for highly active sites of the catalyst can be improved.

[0030] According to the present invention, it is understood that a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products refers to a mixture obtained by hydrogenating non-fused-ring aromatic hydrocarbon compounds as raw materials to a certain extent, wherein the mixture includes non-fused-ring aromatic hydrocarbon compound raw materials and hydrogenation products of non-fused-ring aromatic hydrocarbon compounds.

[0031] According to the present invention, it is understood that those skilled in the art can control the conditions of the hydrogenation reaction according to the desired degree of hydrogenation. The degree of hydrogenation of the hydrogenation product of the non-fused-ring aromatic hydrocarbon compound is not limited, as long as the objectives of the present invention are achieved. In some embodiments, the degree of hydrogenation of the hydrogenation product of the non-fused-ring aromatic hydrocarbon compound in a mixture of the non-fused-ring aromatic hydrocarbon compound and its hydrogenation product is 40%-80% compared to the total hydrogenation product, preferably 55-80%, for example 55%, 57%, 60%, 75%, 71%, 75%, 79%, or 80%. Using the aforementioned embodiments, the different components of the pretreatment solution can better compete for adsorption, thereby improving the selectivity for highly active sites.

[0032] According to some preferred embodiments of the present invention, in the hydrogenation product of the non-fused-ring aromatic hydrocarbon compound, the product of at least one benzene ring undergoing complete hydrogenation accounts for 50%-95%, preferably 70-90%, with the balance being a non-fused-ring aromatic hydrocarbon compound, for example 60%, 65%, 70%, 72%, 78%, 80%, or 90%. By employing the aforementioned embodiments, competitive adsorption with heterocyclic compounds can be adjusted, thereby improving selectivity for highly active sites.

[0033] In this invention, it is understood that the mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products includes products of non-fused-ring aromatic hydrocarbon compounds (at least one product of full hydrogenation of a benzene ring) and non-fused-ring aromatic hydrocarbon compounds.

[0034] In this invention, a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products refers to a mixture of non-fused-ring aromatic hydrocarbon compounds that have undergone a certain degree of hydrogenation reaction. The reaction products are analyzed by gas chromatography, and the mass content of each component is calculated by the area normalization method. The degree of hydrogenation of the hydrogenation products of non-fused-ring aromatic hydrocarbon compounds relative to the total hydrogenation products is calculated by multiplying the content of each component by the sum of the corresponding number of hydrogenation reactions and the number of hydrogen gases required for the total hydrogenation of all raw materials. The proportion of products in which at least one benzene ring is completely hydrogenated in the hydrogenation products of the non-fused-ring aromatic hydrocarbon compounds is calculated by summing the mass contents of one or more benzene ring completely hydrogenated components.

[0035] According to the present invention, the selection of the non-fused-ring aromatic hydrocarbon compound is not limited as long as the purpose of the present invention can be achieved. In some embodiments, the non-fused-ring aromatic hydrocarbon compound contains 1-5 benzene rings in its structure.

[0036] According to the present invention, the selection of the non-fused-ring aromatic hydrocarbon compound is not limited as long as the purpose of the present invention can be achieved. In some embodiments, the non-fused-ring aromatic hydrocarbon compound includes one or more of m-xylene, o-methylphenol, m-isopropyltoluene, benzyltoluene, dibenzyltoluene, and tribenzyltoluene.

[0037] According to some preferred embodiments of the present invention, the non-fused-ring aromatic hydrocarbon compound contains 2-3 benzene rings in its structure.

[0038] According to the present invention, in some preferred embodiments, the non-fused-ring aromatic hydrocarbon compound includes benzyltoluene and / or dibenzyltoluene. Using the aforementioned embodiments, better catalyst stability can be achieved while maintaining better catalyst activity. The inventors hypothesize that the addition of the aforementioned non-fused-ring aromatic hydrocarbon compound can better increase the competitive adsorption among the various combinations, while synergistically acting with other components in the system to improve the activity reduction caused by the poisoning effect of heterocyclic compounds, and improve the selectivity for highly active sites.

[0039] Organic hydrogen storage technology utilizes a reversible reaction between a hydrogen storage organic liquid and hydrogen. According to the present invention, the selection of the hydrogen storage organic liquid is not limited; any hydrogen storage organic liquid that meets the requirements of organic hydrogen storage technology is applicable to the system of the present invention. According to the present invention, in some embodiments, the hydrogen storage organic liquid includes one or more of the following: cyclohexane and / or cyclohexane containing substituent R1; tetrahydronaphthalene and / or tetrahydronaphthalene containing substituent R2; decahydronaphthalene and / or decahydronaphthalene containing substituent R3; perhydronitroethylcarbazole and / or perhydronitroethylcarbazole containing substituent R4; and perhydrocarbazole and / or perhydrocarbazole containing substituent R5; where R1, R2, R3, R4, and R5 are each C1-C3 alkyl or C4-C7 cycloalkyl.

[0040] According to some preferred embodiments of the present invention, the hydrogen storage organic liquid comprises cyclohexane and / or cyclohexane containing substituent R1.

[0041] According to some preferred embodiments of the present invention, R1, R2, R3, R4, and R5 are each C1-C3 alkyl or C5-C6 cycloalkyl, such as methyl, ethyl, propyl, cyclohexyl, or cyclopentyl.

[0042] According to some preferred embodiments of the present invention, the number of each of R1, R2, R3, R4, and R5 is 0 to 3, for example, 0, 1, or 3. When there are 0 of each of R1, R2, R3, R4, or R5, it indicates that there are no substituents.

[0043] According to the present invention, by adopting the aforementioned embodiments, the synergistic effect between the pretreatment liquid components can be increased, and the selectivity for highly active sites can be improved by utilizing the lateral interaction between different components and the competitive adsorption between different components on the catalyst, thereby improving the activity of the poisoned catalyst while improving the stability of the catalyst.

[0044] According to the present invention, by employing the foregoing embodiments, the pretreatment solution of the present invention possesses suitable surface tension and saturated vapor pressure. This enables the pretreatment solution of the present invention to improve selectivity for highly active sites.

[0045] In some embodiments, the surface tension of the pretreatment liquid at room temperature is 28-40 dyn / cm, preferably 30-35 dyn / cm.

[0046] In some embodiments, the pretreatment liquid has a saturated vapor pressure of 4-8 kPa at room temperature, preferably 5-6 kPa.

[0047] According to the present invention, room temperature refers to 20-25℃.

[0048] A second aspect of the present invention provides a method for preparing the pretreatment liquid of the dehydrogenation catalyst, the method comprising:

[0049] The non-fused-ring aromatic hydrocarbon compound S1 was subjected to a hydrogenation reaction to obtain component (c);

[0050] S2 mixes components (a), (b), and (c) to obtain a dehydrogenation catalyst pretreatment solution.

[0051] According to the present invention, as long as a mixture of the hydrogenation product of component (c) of the present invention and optionally the non-fused-ring aromatic hydrocarbon feedstock can be obtained, the conditions of the hydrogenation reaction in step S1 are not limited. In some embodiments, the conditions of the hydrogenation reaction include a reaction temperature of 150-260°C, for example 150°C, 180°C, 200°C, 230°C or 260°C.

[0052] According to the present invention, there is no limitation on the mixing method in step S2, as long as the components (a), (b) and (c) can be mixed evenly. In some embodiments, components (a), (b) and (c) can be added to the mixing container at the same time to obtain the dehydrogenation catalyst pretreatment liquid; in other embodiments, component (c) can be added to component (a) to obtain a mixture, and then component (b) can be added to the mixture to obtain the dehydrogenation catalyst pretreatment liquid.

[0053] According to the present invention, in order to increase the mixing efficiency, mixing can be carried out under conditions such as stirring, shearing, and ultrasound. The mixing method in step S2 will not be described in detail in this invention.

[0054] According to the present invention, in some embodiments, the conditions for the hydrogenation reaction include 10-60 bar, for example 10 bar, 20 bar, 30 bar, 40 bar, 50 bar or 60 bar.

[0055] According to the present invention, in some embodiments, the conditions for the hydrogenation reaction include a stirring rate of 50-200 r / min, for example 50 r / min, 60 r / min, 80 r / min, 150 r / min or 200 r / min.

[0056] According to the present invention, in some embodiments, the conditions for the hydrogenation reaction include: a stable reaction time of 6-24h (e.g., 6h, 8h, 9h, 10h, 15h, 20h or 24h), preferably 6-10h.

[0057] According to the present invention, it is understood that the hydrogenation reaction is a reaction carried out under a hydrogenation catalyst, which includes an active component and a support. In some embodiments, the conditions of the hydrogenation reaction include: the active component in the hydrogenation catalyst includes a noble metal, preferably one or more of gold, palladium, rhodium, and ruthenium; more preferably, the content of the active component is 0.1-1 wt% based on the total mass of the hydrogenation catalyst, for example 0.1 wt%, 0.4 wt%, 0.5 wt%, or 1 wt%.

[0058] According to the present invention, it is understood that those skilled in the art can select the type of hydrogenation catalyst support, such as Al2O3, SiO2 or molecular sieve, as needed.

[0059] By employing the aforementioned embodiments, the hydrogenation product of the non-fused-ring aromatic hydrocarbon compound required by the present invention can be obtained, thereby achieving the purpose of the pretreatment liquid of the present invention to improve the stability of the catalyst while simultaneously increasing the activity of the poisoned catalyst.

[0060] A third aspect of the present invention provides the application of the dehydrogenation catalyst pretreatment liquid in the pretreatment of dehydrogenation catalysts.

[0061] The fourth aspect of the present invention provides the application of the dehydrogenation catalyst pretreatment solution in hydrogen storage dehydrogenation catalysts.

[0062] According to some preferred embodiments of the present invention, the dehydrogenation catalyst contains a dehydrogenation catalyst for hydrogen storage organic liquids.

[0063] Dehydrogenation catalysts can break the CH bonds in organic compounds to achieve dehydrogenation, while maintaining the integrity of the C and C chains. According to the present invention, those skilled in the art will understand that the dehydrogenation catalyst includes an active component and a support. The type of dehydrogenation catalyst is not limited as long as it achieves the purpose of the present invention. In some embodiments, the active component in the dehydrogenation catalyst contains a noble metal, including one or more of gold, palladium, rhodium, and ruthenium. More preferably, the content of the active component is 0.3-2 wt% based on the total mass of the dehydrogenation catalyst, for example, 0.3 wt%, 0.5 wt%, 0.8 wt%, 1 wt%, or 1.5 wt% or 2 wt%.

[0064] According to the present invention, it is understood that those skilled in the art can select the type of dehydrogenation catalyst support, such as Al2O3, SiO2 or molecular sieve, as needed.

[0065] According to the present invention, those skilled in the art will understand that, in order to increase the activity of the dehydrogenation catalyst, in some embodiments, the dehydrogenation catalyst further includes an active agent containing a transition metal element, such as molybdenum or nickel.

[0066] According to the present invention, in some embodiments, the content of the active additive is 2-5 wt% based on the total mass of the dehydrogenation catalyst, for example 2 wt%, 2.5 wt%, 3 wt%, 4 wt%, or 5 wt%.

[0067] According to the present invention, the dehydrogenation catalyst pretreatment liquid can be used to pretreat the dehydrogenation catalyst used in hydrogen storage organic liquid, thereby improving the selectivity for highly active sites, reducing the atomic sites provided on the catalyst surface for carbonaceous growth, and improving the selectivity for highly active sites through the synergistic effect between the various combinations in the dehydrogenation catalyst pretreatment liquid.

[0068] The fifth aspect of the present invention provides a method for pretreating a dehydrogenation catalyst, the method comprising: contacting the dehydrogenation catalyst pretreatment solution with the dehydrogenation catalyst under pretreatment conditions to pretreat, thereby obtaining a pretreated dehydrogenation catalyst.

[0069] According to the present invention, the pretreatment conditions are not limited as long as the purpose of the present invention can be achieved. In some embodiments, the pretreatment conditions include: the mass hourly space velocity of the dehydrogenation catalyst pretreatment solution is 0.5-5 h⁻¹. -1 For example, 0.5h -1 1h -1 2h -1 3h -1 4h -1 or 5h -1 .

[0070] According to the present invention, in some embodiments, the pretreatment conditions include: the pretreatment pressure is 1-5 bar, for example 1 bar, 2 bar, 3 bar, 4 bar or 5 bar.

[0071] According to the present invention, in some embodiments, the pretreatment conditions include a pretreatment temperature of 240-360°C, for example 240°C, 250°C, 260°C, 280°C, 300°C, 320°C, 350°C or 360°C.

[0072] According to the present invention, in some embodiments, the pretreatment conditions include a pretreatment time of 6-12 hours, such as 6 hours, 7 hours, 8 hours, 10 hours or 12 hours.

[0073] According to the present invention, in some embodiments, the dehydrogenation catalyst comprises a dehydrogenation catalyst for hydrogen storage organic liquids.

[0074] According to the present invention, in some embodiments, the active component in the dehydrogenation catalyst contains a noble metal, including one or more of gold, palladium, rhodium, and ruthenium; more preferably, the content of the active component is 0.3-2 wt% based on the total mass of the dehydrogenation catalyst.

[0075] According to the present invention, in some embodiments, the dehydrogenation catalyst further includes an active promoter containing a transition metal element, preferably, the content of the active promoter is 2-5 wt% based on the total mass of the dehydrogenation catalyst.

[0076] According to the present invention, pretreating the dehydrogenation catalyst with the aforementioned dehydrogenation catalyst pretreatment solution can provide selectivity of the catalyst for highly active sites, thereby improving the activity of the poisoned catalyst while improving the catalyst stability.

[0077] The sixth aspect of this invention provides a method for dehydrogenating a hydrogen-storing organic liquid, the method comprising:

[0078] (1) Pre-treat the dehydrogenation catalyst according to the pre-treatment method described above;

[0079] (2) Under dehydrogenation conditions, the hydrogen storage organic liquid is brought into contact with the pretreated dehydrogenation catalyst to react.

[0080] According to the present invention, those skilled in the art can select the desired dehydrogenation conditions as needed. In some embodiments, the dehydrogenation conditions include a reaction pressure of 1-10 bar, such as 1 bar, 2 bar, 4 bar, 5 bar, 6 bar, 7 bar, 8 bar, 9 bar, or 10 bar.

[0081] According to the present invention, in some embodiments, the dehydrogenation conditions include a reaction temperature of 220-360°C, for example 220°C, 300°C or 350°C.

[0082] According to the present invention, in some embodiments, the dehydrogenation conditions include a mass hourly space velocity (MSV) of 2-10 h⁻¹. -1 For example, 2h -1 3h -1 4h -1 5h -1 7h -1 8h -1 9h -1 or 10h -1 .

[0083] According to the present invention, those skilled in the art can choose to dehydrogenate the hydrogen storage organic liquid as needed. In the embodiments of the present invention, cyclohexane is used as an example raw material to illustrate the advantages of the present invention, but the present invention is not limited thereto.

[0084] According to the present invention, after pretreating the catalyst for dehydrogenation of hydrogen storage organic liquid with the dehydrogenation catalyst pretreatment solution described in the present invention, the activity of the poisoned catalyst is improved while the stability of the catalyst is improved.

[0085] Example 1

[0086] Preparation of a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products: 5 g of 0.4 wt% Ru / Al2O3 catalyst and 50 g of dibenzyltoluene were placed in a reactor, 10 bar of hydrogen gas was introduced, the temperature was raised to 200 °C, and the pressure inside the reactor was maintained at 30 bar. The stirring rate was 80 r / min, and the reaction was stabilized for 6 h to obtain a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products (the mixture contains at least one product of complete hydrogenation of a benzene ring and the non-fused-ring aromatic hydrocarbon compound dibenzyltoluene). The degree of hydrogenation and the proportion of products of complete hydrogenation of at least one benzene ring in the mixture were analyzed by gas chromatography.

[0087] Preparation of dehydrogenation catalyst pretreatment liquid: 5g of a mixture of hydrogenation products containing non-fused-ring aromatic hydrocarbons was mixed with 94.9994g of cyclohexane and 0.0006g of quinoline to obtain a dehydrogenation catalyst pretreatment liquid. The surface tension of the liquid was measured by a surface tension meter, and the saturated vapor pressure was measured by a saturated vapor pressure meter.

[0088] Dehydrogenation of hydrogen-storage organic liquid: 5g of 0.5wt%Pd-1.2wt%Mo / Al2O3 catalyst was loaded into a reaction tube, heated to 300℃, and a dehydrogenation catalyst pretreatment solution was introduced. The mass hourly space velocity (HHSV) of the dehydrogenation catalyst pretreatment solution was adjusted to 2h. -1 The system pressure was maintained at 1 bar. After stabilizing the reaction for 8 hours, the flow of the dehydrogenation catalyst pretreatment solution was stopped. Then, the temperature was raised to 350°C, and cyclohexane was introduced as a feedstock for the dehydrogenation reaction. The system pressure was increased to 4 bar, and the cyclohexane mass hourly space velocity was adjusted to 5 h⁻¹. -1 The reaction was stabilized for 4 hours, and the initial dehydrogenation conversion was obtained by online sampling using gas chromatography; the mass space velocity was adjusted to 20 h⁻¹. -1 After stabilizing the reaction for 24 hours, the mass hourly space velocity (MHSV) was adjusted to 5 h⁻¹. -1 The conversion rate was obtained after a stable reaction of 4 hours and a high-space-velocity reaction of 24 hours.

[0089] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0090] Example 2

[0091] The method is the same as in Example 1, except that:

[0092] Preparation of dehydrogenation catalyst pretreatment liquid: 5g of a mixture of hydrogenation products containing non-fused-ring aromatic hydrocarbons was mixed with 94.9994g of cyclohexane and 0.0006g of piperidine to obtain a dehydrogenation catalyst pretreatment liquid. The surface tension of the liquid was measured by a surface tension meter, and the saturated vapor pressure was measured by a saturated vapor pressure meter.

[0093] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0094] Example 3

[0095] The method is the same as in Example 1, except that:

[0096] Dehydrogenation of hydrogen-storage organic liquid: 5g of 0.5wt%Pd-1.2wt%Ni / Al2O3 catalyst was loaded into a reaction tube, heated to 300℃, and a dehydrogenation catalyst pretreatment solution was introduced. The mass hourly space velocity (H₂S₀) of the dehydrogenation catalyst pretreatment solution was adjusted to 2h₁₀. -1 The system pressure was maintained at 1 bar. After stabilizing the reaction for 8 hours, the flow of the dehydrogenation catalyst pretreatment solution was stopped. Then, the temperature was raised to 350°C, and cyclohexane was introduced as a feedstock for the dehydrogenation reaction. The system pressure was increased to 4 bar, and the cyclohexane mass hourly space velocity was adjusted to 5 h⁻¹. -1 The reaction was stabilized for 4 hours, and the initial dehydrogenation conversion was obtained by online gas chromatography sampling. The mass space velocity was then adjusted to 20 h⁻¹. -1 After stabilizing the reaction for 24 hours, the mass hourly space velocity (MHSV) was adjusted to 5 h⁻¹. -1 The conversion rate was obtained after a stable reaction of 4 hours and a high-space-velocity reaction of 24 hours.

[0097] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0098] Example 4

[0099] The method is the same as in Example 1, except that:

[0100] Preparation of a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products: 5 g of 0.4 wt% Ru / Al2O3 catalyst and 50 g of dibenzyltoluene were placed in a reactor, 10 bar of hydrogen gas was introduced, the temperature was raised to 200 °C, and the pressure inside the reactor was maintained at 30 bar. The stirring rate was 80 r / min, and the reaction was stabilized for 8 h to obtain a mixture of hydrogenation products containing non-fused-ring aromatic hydrocarbon compounds. The degree of hydrogenation was analyzed by gas chromatography.

[0101] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0102] Example 5

[0103] The method is the same as in Example 1, except that:

[0104] Preparation of dehydrogenation catalyst pretreatment liquid: 7g of a mixture of hydrogenation products containing non-fused-ring aromatic hydrocarbons was mixed with 92.9994g of cyclohexane and 0.0006g of quinoline to obtain a dehydrogenation catalyst pretreatment liquid. The surface tension of the liquid was measured by a surface tension meter, and the saturated vapor pressure was measured by a saturated vapor pressure meter.

[0105] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0106] Example 6

[0107] The method is the same as in Example 1, except that:

[0108] Preparation of a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products: 5 g of 0.4 wt% Ru / Al2O3 catalyst and 50 g of dibenzyltoluene were placed in a reactor, 10 bar of hydrogen gas was introduced, the temperature was raised to 260 °C, and the pressure inside the reactor was maintained at 30 bar. The stirring rate was 80 r / min, and the reaction was stabilized for 6 h to obtain a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products (the mixture contains at least one product of complete hydrogenation of a benzene ring and the non-fused-ring aromatic hydrocarbon compound dibenzyltoluene). The degree of hydrogenation and the proportion of products of complete hydrogenation of at least one benzene ring in the mixture were analyzed by gas chromatography.

[0109] Dehydrogenation of hydrogen-storage organic liquid: 5g of 0.5wt%Pd-1.2wt%Mo / Al2O3 catalyst was loaded into a reaction tube, heated to 300℃, and a dehydrogenation catalyst pretreatment solution was introduced. The mass hourly space velocity (HHSV) of the dehydrogenation catalyst pretreatment solution was adjusted to 2h. -1 After maintaining the system pressure at 1 bar and stabilizing the reaction for 12 hours, the flow of the dehydrogenation catalyst pretreatment solution was stopped. Then, the temperature was raised to 350°C, and cyclohexane was introduced as a feedstock for the dehydrogenation reaction. The system pressure was increased to 4 bar, and the mass hourly space velocity was adjusted to 5 h⁻¹. -1 The reaction was stabilized for 4 hours, and the initial dehydrogenation conversion was obtained by online gas chromatography sampling. The mass space velocity was then adjusted to 20 h⁻¹. -1 After stabilizing the reaction for 24 hours, the mass hourly space velocity (MHSV) was adjusted to 5 h⁻¹. -1 The conversion rate was obtained after a stable reaction of 4 hours and a high-space-velocity reaction of 24 hours.

[0110] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0111] Example 7

[0112] The method is the same as in Example 1, except that:

[0113] Dehydrogenation of hydrogen-storage organic liquid: 5g of 0.5wt%Pd-1.2wt%Mo / Al2O3 catalyst was loaded into a reaction tube, heated to 360℃, and a dehydrogenation catalyst pretreatment solution was introduced. The mass hourly space velocity (HHSV) of the dehydrogenation catalyst pretreatment solution was adjusted to 2h. -1 The system pressure was maintained at 1 bar. After stabilizing the reaction for 8 hours, the flow of the dehydrogenation catalyst pretreatment solution was stopped. Then, the temperature was lowered to 350°C, and cyclohexane was introduced as a feedstock for the dehydrogenation reaction. The system pressure was increased to 4 bar, and the cyclohexane mass hourly space velocity was adjusted to 5 h⁻¹. -1 The reaction was stabilized for 4 hours, and the initial dehydrogenation conversion was obtained by online gas chromatography sampling. The mass space velocity was then adjusted to 20 h⁻¹. -1 After stabilizing the reaction for 24 hours, the mass hourly space velocity (MHSV) was adjusted to 5 h⁻¹. -1 The conversion rate was obtained after a stable reaction of 4 hours and a high-space-velocity reaction of 24 hours.

[0114] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0115] Example 8

[0116] The method is the same as in Example 1, except that:

[0117] Preparation of dehydrogenation catalyst pretreatment liquid: 5g of a mixture of hydrogenation products containing non-fused-ring aromatic hydrocarbons was mixed with 94.9985g of cyclohexane and 0.0015g of quinoline to obtain a dehydrogenation catalyst pretreatment liquid. The surface tension of the liquid was measured by a surface tension meter, and the saturated vapor pressure was measured by a saturated vapor pressure meter.

[0118] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0119] Example 9

[0120] The method is the same as in Example 1, except that:

[0121] Preparation of a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products: 5 g of 0.4 wt% Ru / Al2O3 catalyst and 50 g of benzyltoluene were placed in a reactor, 10 bar of hydrogen gas was introduced, the temperature was raised to 200 °C, and the pressure inside the reactor was maintained at 30 bar. The stirring rate was 80 r / min, and the reaction was stabilized for 6 h to obtain a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products (the mixture contains products of at least one benzene ring fully hydrogenated and the non-fused-ring aromatic hydrocarbon compound benzyltoluene). The degree of hydrogenation and the proportion of products of at least one benzene ring fully hydrogenated in the mixture were analyzed by gas chromatography.

[0122] Preparation of dehydrogenation catalyst pretreatment liquid: 5g of a mixture of hydrogenation products containing non-fused-ring aromatic hydrocarbons was mixed with 94.9998g of cyclohexane and 0.0002g of quinoline to obtain a dehydrogenation catalyst pretreatment liquid. The surface tension of the liquid was measured by a surface tension meter, and the saturated vapor pressure was measured by a saturated vapor pressure meter.

[0123] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0124] Example 10

[0125] The method is the same as in Example 1, except that:

[0126] Preparation of a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products: 5 g of 0.4 wt% Ru / Al2O3 catalyst and 50 g of dibenzyltoluene were placed in a reactor, 10 bar of hydrogen gas was introduced, the temperature was raised to 170 °C, and the pressure inside the reactor was maintained at 25 bar. The stirring rate was 80 r / min, and the reaction was stabilized for 3 h to obtain a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products (the mixture contains products of at least one benzene ring fully hydrogenated and the non-fused-ring aromatic hydrocarbon compound dibenzyltoluene). The degree of hydrogenation and the proportion of products of at least one benzene ring fully hydrogenated in the mixture were analyzed by gas chromatography.

[0127] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0128] Example 11

[0129] The method is the same as in Example 1, except that:

[0130] Preparation of dehydrogenation catalyst pretreatment liquid: 9g of a mixture of hydrogenation products containing non-fused-ring aromatic hydrocarbons was mixed with 90.996g of cyclohexane and 0.004g of quinoline to obtain the dehydrogenation catalyst pretreatment liquid. The surface tension of the liquid was measured by a surface tension meter, and the saturated vapor pressure was measured by a saturated vapor pressure meter.

[0131] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0132] Example 12

[0133] The method is the same as in Example 1, except that:

[0134] Preparation of dehydrogenation catalyst pretreatment liquid: 5g of a mixture of hydrogenation products containing non-fused-ring aromatic hydrocarbons was mixed with 94.9994g of cyclohexane and 0.0006g of thiophene to obtain a dehydrogenation catalyst pretreatment liquid. The surface tension of the liquid was measured by a surface tension meter, and the saturated vapor pressure was measured by a saturated vapor pressure meter.

[0135] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0136] Example 13

[0137] The method is the same as in Example 1, except that:

[0138] Preparation of a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products: 5 g of 0.4 wt% Ru / Al2O3 catalyst and 50 g of dibenzyltoluene were placed in a reactor, 10 bar of hydrogen gas was introduced, the temperature was raised to 230 °C, and the pressure inside the reactor was maintained at 30 bar. The stirring rate was 80 r / min, and the reaction was stabilized for 11 h to obtain a mixture of non-fused-ring aromatic hydrocarbon compounds and their hydrogenation products (the mixture contains products of complete hydrogenation of at least one benzene ring and the non-fused-ring aromatic hydrocarbon compound dibenzyltoluene). The degree of hydrogenation and the proportion of products of complete hydrogenation of at least one benzene ring in the mixture were analyzed by gas chromatography.

[0139] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0140] Comparative Example 1

[0141] Dehydrogenation of hydrogen-storage organic liquid: 5g of 0.5wt% Pd-1.2wt% Mo / Al2O3 catalyst was loaded into a reaction tube, heated to 350℃, and cyclohexane was introduced as a feedstock for the dehydrogenation reaction. The system pressure was increased to 4 bar, and the mass hourly space velocity was adjusted to 5 h⁻¹. -1 The reaction was stabilized for 4 hours, and the initial dehydrogenation conversion was obtained by online gas chromatography sampling. The mass space velocity was then adjusted to 20 h⁻¹. -1 After stabilizing the reaction for 24 hours, the mass hourly space velocity (MHSV) was adjusted to 5 h⁻¹. -1 The conversion rate was obtained after a stable reaction of 4 hours and a high-space-velocity reaction of 24 hours.

[0142] The initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0143] Comparative Example 2

[0144] Preparation of dehydrogenation catalyst pretreatment solution: 99.9994 g of cyclohexane and 0.0006 g of quinoline were mixed by stirring to obtain the dehydrogenation catalyst pretreatment solution;

[0145] Dehydrogenation of hydrogen-storage organic liquid: 5g of 0.5wt%Pd-1.2wt%Mo / Al2O3 catalyst was loaded into a reaction tube, heated to 300℃, and a dehydrogenation catalyst pretreatment solution was introduced. The mass hourly space velocity was adjusted to 2h. -1 The system pressure was maintained at 1 bar, and after stabilizing the reaction for 8 hours, the temperature was increased to 350°C. Cyclohexane was then introduced as a feedstock for dehydrogenation, and the system pressure was increased to 4 bar. The mass hourly space velocity was adjusted to 5 h⁻¹. -1 The reaction was stabilized for 4 hours, and the initial dehydrogenation conversion was obtained by online gas chromatography sampling. The mass space velocity was then adjusted to 20 h⁻¹. -1 After stabilizing the reaction for 24 hours, the mass hourly space velocity (MHSV) was adjusted to 5 h⁻¹. -1 The conversion rate was obtained after a stable reaction of 4 hours and a high-space-velocity reaction of 24 hours.

[0146] The degree of hydrogenation of the hydrogenated products in the mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products compared to the total hydrogenated products, the proportion of products with at least one benzene ring fully hydrogenated, the surface tension and saturated vapor pressure of the dehydrogenation catalyst pretreatment liquid, and the initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of the hydrogen storage organic liquid are shown in Table 1.

[0147] Comparative Example 3

[0148] Preparation of dehydrogenation catalyst pretreatment solution: Take 0.003 g of dimethyl disulfide and 99.997 g of cyclohexane, stir and mix to obtain dehydrogenation catalyst pretreatment solution.

[0149] Dehydrogenation of hydrogen-storage organic liquid: 5g of 0.5wt%Pd-1.2wt%Mo / Al2O3 catalyst was loaded into a reaction tube, heated to 200℃, and a dehydrogenation catalyst pretreatment solution was introduced. The mass hourly space velocity (WHSV) of the dehydrogenation catalyst pretreatment solution was adjusted to 2h. -1 Maintaining the system pressure at 1 bar, the temperature was increased to 300°C at a rate of 2°C / min and stabilized for 8 hours. The flow of the dehydrogenation catalyst pretreatment solution was then stopped. The temperature was then increased to 350°C, and cyclohexane was introduced as a feedstock for the dehydrogenation reaction. The system pressure was increased to 4 bar, and the cyclohexane mass hourly space velocity was adjusted to 5 h⁻¹. -1 The reaction was stabilized for 4 hours, and the initial dehydrogenation conversion was obtained by online sampling using gas chromatography; the mass space velocity was adjusted to 20 h⁻¹. -1 After stabilizing the reaction for 24 hours, the mass hourly space velocity (MHSV) was adjusted to 5 h⁻¹. -1 The conversion rate was obtained after a stable reaction of 4 hours and a high-space-velocity reaction of 24 hours.

[0150] The initial dehydrogenation conversion rate and the dehydrogenation conversion rate after 24 h of hydrogen storage organic liquid dehydrogenation are shown in Table 1.

[0151] Table 1

[0152]

[0153] As can be seen from the results in Table 1, Examples 1-13, which use the pretreatment liquid of the dehydrogenation catalyst made from the mixture of hydrogen storage organic liquid, heterocyclic compound, and hydrogenation product containing non-fused-ring aromatic hydrocarbon compound of the present invention, improve the activity of the poisoned catalyst while improving the stability of the catalyst.

[0154] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A pretreatment solution for a dehydrogenation catalyst, characterized in that, Include: (a) Hydrogen-storing organic liquid; (b) Heterocyclic compounds; (c) A mixture of non-fused-ring aromatic hydrocarbons and their hydrogenation products; In mixtures of non-fused-ring aromatic hydrocarbons and their hydrogenation products, the degree of hydrogenation of the hydrogenation products of the non-fused-ring aromatic hydrocarbons is 40%-80% compared to that of the fully hydrogenated products; In the mixture of the non-fused-ring aromatic hydrocarbon compound and its hydrogenation product, the product of at least one benzene ring being fully hydrogenated accounts for 50%-95%, and the remainder is a non-fused-ring aromatic hydrocarbon compound. The hydrogen storage organic liquid includes cyclohexane; The non-fused-ring aromatic hydrocarbon compound includes one or more of m-xylene, m-isopropyltoluene, benzyltoluene, dibenzyltoluene, and tribenzyltoluene; Based on 100 parts by weight, the pretreatment solution comprises: (a) 90-98 parts of hydrogen-storing organic liquid, (b) 0.0001-0.005 parts of heterocyclic compound, and (c) 2-10 parts of a mixture of non-fused-ring aromatic hydrocarbon compound and its hydrogenation products.

2. The pretreatment solution according to claim 1, wherein, The heteroatom in the heterocyclic compound includes one or more of N, S, P, and O; and / or The total number of heteroatoms in the heterocyclic compound is 1-3; and / or The heterocyclic compound has 1-5 cyclic structures; and / or The cyclic structure in the heterocyclic compound is at least a three-membered ring structure.

3. The pretreatment solution according to claim 2, wherein, The heteroatom in the heterocyclic compound includes at least one N; and / or The total number of heteroatoms in the heterocyclic compound is 1-2; and / or The heterocyclic compound has 1-3 cyclic structures; and / or The cyclic structure in the heterocyclic compound is a 5-8 membered ring structure.

4. The pretreatment solution according to claim 1, wherein, Based on 100 parts by weight, the pretreatment solution comprises: (a) 92-95 parts of hydrogen-storing organic liquid, (b) 0.0002-0.0015 parts of heterocyclic compound, and (c) 5-8 parts of a mixture of non-fused-ring aromatic hydrocarbon compound and its hydrogenation products.

5. The pretreatment solution according to claim 1, wherein, The heterocyclic compounds include one or more of the following: quinoline compounds, piperidine compounds, pyrrole compounds, imidazole compounds, pyrazine compounds, pyrimidine compounds, acridine compounds, thiophene compounds, furan compounds, and carbazole compounds; In mixtures of non-fused-ring aromatic hydrocarbons and their hydrogenation products, the degree of hydrogenation of the hydrogenation products of the non-fused-ring aromatic hydrocarbons is 55-80% compared to that of the fully hydrogenated products; In the mixture of the non-fused-ring aromatic hydrocarbon compound and its hydrogenation product, the product of complete hydrogenation of at least one benzene ring accounts for 70-90%, and the remainder is a non-fused-ring aromatic hydrocarbon compound.

6. The pretreatment solution according to claim 5, wherein, The heterocyclic compounds include quinoline compounds and / or piperidine compounds.

7. The pretreatment solution according to claim 1, wherein, The non-fused-ring aromatic hydrocarbon compounds include benzyltoluene and / or dibenzyltoluene.

8. The pretreatment solution according to any one of claims 1-7, wherein, The surface tension of the pretreatment liquid at room temperature is 28-40 dyn / cm; and / or The pretreatment liquid has a saturated vapor pressure of 4-8 kPa at room temperature.

9. The pretreatment solution according to claim 8, wherein, The surface tension of the pretreatment liquid at room temperature is 30-35 dyn / cm; and / or The pretreatment liquid has a saturated vapor pressure of 5-6 kPa at room temperature.

10. A method for preparing a dehydrogenation catalyst pretreatment solution according to any one of claims 1-9, characterized in that, The method includes: S1 Non-fused-ring aromatic hydrocarbon compound undergoes hydrogenation reaction to obtain component (c); S2. Components (a), (b), and (c) are mixed to obtain a dehydrogenation catalyst pretreatment solution; The conditions for the hydrogenation reaction in step S1 include: The reaction temperature is 150-260℃; The reaction pressure is 10-60 bar; The stirring rate is 50-200 r / min; The stable reaction time is 6-24 hours; The hydrogenation catalyst includes an active component and a support, wherein the active component in the hydrogenation catalyst includes a noble metal.

11. The method according to claim 10, wherein, The conditions for the hydrogenation reaction in step S1 include: a stable reaction time of 6-10 h; and / or The precious metal includes one or more of gold, palladium, rhodium, and ruthenium; and / or The content of the active component is 0.1-1 wt% based on the total mass of the hydrogenation catalyst.

12. The application of the dehydrogenation catalyst pretreatment liquid according to any one of claims 1-9 in the pretreatment of dehydrogenation catalysts.

13. The use of the dehydrogenation catalyst pretreatment liquid according to any one of claims 1-9 in the dehydrogenation catalyst.

14. The application according to claim 13, wherein, The dehydrogenation catalyst contains a dehydrogenation catalyst for hydrogen storage organic liquids.

15. The application according to claim 13, wherein, The active component in the dehydrogenation catalyst contains a noble metal, which includes one or more of gold, palladium, rhodium, and ruthenium.

16. The application according to claim 15, wherein, The content of the active ingredient is 0.3-2 wt% based on the total mass of the dehydrogenation catalyst; and / or The dehydrogenation catalyst also includes an active promoter, which contains transition metal elements based on the total mass of the dehydrogenation catalyst.

17. The application according to claim 16, wherein, The content of the active additive is 2-5 wt%.

18. A pretreatment method for a dehydrogenation catalyst, characterized in that, The method includes: Under pretreatment conditions, the dehydrogenation catalyst pretreatment solution according to any one of claims 1-9 is contacted with the dehydrogenation catalyst for pretreatment to obtain the pretreated dehydrogenation catalyst; The preprocessing conditions include: The mass hourly space velocity (MSV) of the pretreated solution for the dehydrogenation catalyst is 0.5-5 h⁻¹. -1 ; Pretreatment pressure is 1-5 bar; The pretreatment temperature is 240-360℃; The pretreatment time is 6-12 hours.

19. The method according to claim 18, wherein, The dehydrogenation catalyst contains a dehydrogenation catalyst for hydrogen storage organic liquids.

20. The method according to claim 18, wherein, The active component in the dehydrogenation catalyst contains a noble metal, which includes one or more of gold, palladium, rhodium, and ruthenium.

21. The method according to claim 20, wherein, The content of the active ingredient is 0.3-2 wt% based on the total mass of the dehydrogenation catalyst; and / or The dehydrogenation catalyst also includes an active additive, which contains a transition metal element.

22. The method according to claim 21, wherein, The content of active additives is 2-5 wt% based on the total mass of the dehydrogenation catalyst.

23. A method for dehydrogenating a hydrogen-storing organic liquid, characterized in that, The method includes: (1) Preprocessing according to any one of claims 18-22; (2) Under dehydrogenation conditions, the hydrogen storage organic liquid is brought into contact with the pretreated dehydrogenation catalyst for reaction.

24. The method according to claim 23, wherein, The dehydrogenation conditions include: The reaction pressure is 1-10 bar; and / or The reaction temperature is 220-360℃; and / or Mass hourly space velocity (MHSV) is 2-10 h -1 .

Images