A catalyst for preparing perhydrophenanthrene by hydrorefining and a preparation method and application thereof

Abstract

The application belongs to the technical field of organic matter addition catalysts, and specifically discloses a catalyst for preparing perhydrophenanthrene through phenanthrene hydrogenation as well as a preparation method and application thereof. A nickel source, an aluminum source, citric acid and water are mixed to obtain a sol; the sol is dried and then calcined to obtain a catalyst intermediate product; the catalyst intermediate product is reduced to obtain a nickel / nickel-like aluminum spinel catalyst; the catalyst is mixed with a palladium source and a boron source, dried and then calcined to obtain the catalyst for preparing perhydrophenanthrene through phenanthrene hydrogenation. The catalyst for preparing perhydrophenanthrene through phenanthrene hydrogenation prepared by the application has relatively low preparation cost, good catalytic activity and selectivity in the reaction of preparing perhydrophenanthrene through phenanthrene hydrogenation, and is not prone to catalyst poisoning, and has good stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic addition catalysts, in particular to a catalyst for preparing perhydrophenanthrene by hydrogenation of phenanthrene and a preparation method and application thereof. BACKGROUND

[0002] Efficient and clean utilization of coal is an important way to alleviate the shortage of oil resources and find substitutes for oil raw materials. Coal tar is mainly derived from coal pyrolysis and dry distillation. The composition of coal tar is very complex. Coal tar is rich in polycyclic aromatic hydrocarbons. The content of naphthalene in medium-low temperature coal tar is about 3wt%, and the content of phenanthrene and anthracene is about 1wt%. After treating the components in coal tar by chemical and physical methods, high value-added chemicals and high performance fuels can be prepared, and the deep processing and utilization of coal tar can be realized. For example, perhydrophenanthrene prepared by full addition reaction of phenanthrene in coal tar has high density, high heat value, high thermal stability and other characteristics, and is an ideal component of high energy density fuel used in the field of aerospace.

[0003] At present, the definition of high energy density fuel is that the density is > 0.8g / cm 3 , and the combustion heat value is > 32MJ / L. Taking perhydrophenanthrene as an example, which is the product of hydrogenation saturation of phenanthrene, the relative density is 0.938g / cm 3 , and the heat value calculated by HSC is about 42.6MJ / L. The density and heat value of perhydrophenanthrene meet the requirements of high energy density fuel. In addition, perhydrophenanthrene can also be used to produce high-tension cage compounds such as diamondoids by hydrogenation isomerization, which can be used to produce high energy density fuel with better performance.

[0004] Polycyclic aromatic hydrocarbon hydrogenation saturation catalysts are mainly divided into sulfide catalysts, noble metal catalysts, noble metal-like catalysts and non-noble metal catalysts according to different active components. Among them, sulfide catalysts have lower cost, stronger sulfur and nitrogen resistance, but the hydrogenation activity is weaker than noble metal catalysts. Noble metal catalysts have strong ability to dissociate hydrogen atoms and activate aromatic molecules, and have high hydrogenation saturation performance at low temperature, but are easily poisoned by sulfur and nitrogen compounds. Non-noble metal catalysts such as Ni and Mo also have good hydrogenation activity, and the cost is lower than noble metal, which can be used as active metal alone. In addition, Ni, Mo and other metals form carbide, nitride and phosphide catalysts after adding C, N and P elements, and the hydrogenation activity can be comparable to noble metal catalysts, which are called noble metal-like catalysts. The structures of active sites of the four types of catalysts are different, and the main factors affecting their hydrogenation activity are also different.

[0005] Chinese patent application CN 116393133 A discloses a supported nickel-based catalyst, which comprises a support and an active component, the active component comprises NiAl2O4 spinel, and the support comprises Al2O3; which can be used for catalyzing the hydrogenation reaction of adiponitrile to prepare hexamethylenediamine. But it has low selectivity for preparing perhydrophenanthrene by phenanthrene hydrogenation.

[0006] In view of the problems of the above-mentioned catalyst, we disclose a Ni / NiAlO x The catalyst has the advantages of low preparation cost, high catalytic activity and high catalytic selectivity. However, it is found that the selectivity of perhydrophenanthrene decreases with the reaction, even if some improvement directions are proposed, but the improvement effect is still not ideal, the main reason is that the electronic structure of the active component Ni of the catalyst changes during the reaction, the degree of "electron deficiency" increases gradually, which is not conducive to the adsorption of aromatic hydrocarbons, in addition, the catalytic activity and catalytic selectivity of the catalyst still need to be improved.

[0007] Therefore, how to disclose a catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation and its preparation method and application, which can improve the stability of the catalyst, further improve the catalytic activity and catalytic selectivity while ensuring low preparation cost, is a difficult problem to be solved in the field. SUMMARY

[0008] Therefore, the present application provides a catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation and its preparation method and application, which can solve the problems of poor stability of the existing catalyst, and the catalytic activity and selectivity still need to be improved.

[0009] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0010] A preparation method of a catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation, comprising the following steps:

[0011] 1) mixing a nickel source, an aluminum source, citric acid and water to obtain a sol;

[0012] 2) drying the sol and then calcining to obtain a catalyst intermediate product;

[0013] 3) reducing the catalyst intermediate product to obtain a nickel / nickel-like aluminum spinel catalyst;

[0014] 4) mixing the nickel / nickel-like aluminum spinel catalyst with a palladium source and a boron source, drying and then calcining to obtain a catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation.

[0015] Preferably, the molar ratio of nickel in the nickel source and aluminum in the aluminum source in step 1) is 1.2-1.5:2; the total molar ratio of nickel in the nickel source and aluminum in the aluminum source, citric acid and water is 1:0.1-3:20-70;

[0016] The nickel source comprises nickel nitrate and / or nickel acetate; the aluminum source comprises aluminum nitrate and / or aluminum acetate.

[0017] Preferably, the temperature of the calcination in step 2) is 450-900℃, and the time of the calcination is 1-3h.

[0018] Preferably, the reduction in step 3) comprises reacting the catalyst intermediate with hydrogen.

[0019] Preferably, the temperature of the reduction is 450-750℃, the time of the reduction is 3-8h, and the flow rate of hydrogen is 40-100mL / min.

[0020] Preferably, the palladium source comprises palladium acetate solution and / or palladium nitrate solution; the boron source comprises ammonium borate solution.

[0021] Preferably, the mass ratio of the nickel / nickel-like aluminum spinel catalyst, palladium in the palladium source and boron in the boron source is 100:0.002-0.005:0.8-1.5.

[0022] Preferably, the temperature of the calcination in step 4) is 350-420℃, and the time of the calcination is 1-3h.

[0023] Another object of the present application is to provide a catalyst for preparing full-hydrogen phenanthrene by phenanthrene hydrogenation, which is prepared by the preparation method.

[0024] Still another object of the present application is to provide an application of the catalyst in full-hydrogen phenanthrene by phenanthrene hydrogenation.

[0025] According to the technical solution above, compared with the prior art, the present application has the following beneficial effects:

[0026] 1. In the nickel / nickel-like aluminum spinel catalyst obtained by the present application, Ni has three occurrence forms: free Ni, nickel-aluminum spinel structure tetrahedral site Ni 2+ and octahedral site Ni 2+ . About 99% of the Ni 2+ occupies the octahedral site of the nickel-aluminum spinel. The distribution improves the dispersion of Ni, and at the same time, gives the catalyst after reduction a strong interaction between the metal and the carrier, forming a metal Ni electron-deficient structure.

[0027] 2、The present application improves the stability of the catalyst by doping palladium and boron: the electronic structure and state of palladium can affect the surrounding active nickel, and this effect can adjust the electron cloud distribution of nickel, so that nickel is more likely to maintain an "electron-deficient" state. By adjusting the electronic structure, palladium can enhance the stability of nickel; the addition of boron can provide additional electrons, making the electronic state of nickel more stable; in addition, palladium and boron can also form an alloy with nickel, and doping palladium and boron can reduce the Fermi level of the material, making it easier for electrons to be excited and flow, improving the stability of the electronic state, and thus improving the stability of the catalyst.

[0028] 3、In addition to improving the stability of the catalyst, the catalytic activity and selectivity of the catalyst are also greatly improved, because the change of the active component in the catalyst disclosed in the present application brings stronger catalytic effect. DETAILED DESCRIPTION

[0029] A preparation method of a catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation, comprising the following steps:

[0030] 1) mixing a nickel source, an aluminum source, citric acid and water to obtain a sol;

[0031] 2) drying the sol and then calcining to obtain a catalyst intermediate product;

[0032] 3) reducing the catalyst intermediate product to obtain a nickel / nickel-like aluminum spinel catalyst;

[0033] 4) mixing the nickel / nickel-like aluminum spinel catalyst with a palladium source and a boron source, drying and then calcining to obtain a catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation.

[0034] In the present application, the molar ratio of nickel in the nickel source to aluminum in the aluminum source in step 1) is 1.2-1.5:2, preferably 1.3-1.5:2, further preferably 1.4-1.5:2, and more preferably 1.45:2; the total moles of nickel in the nickel source and aluminum in the aluminum source to the moles of citric acid and water are 1:0.1-3:20-70, preferably 1:0.5-2:30-50, and further preferably 1:1:40.

[0035] In the present application, the nickel source includes nickel nitrate and / or nickel acetate; the aluminum source includes aluminum nitrate and / or aluminum acetate.

[0036] In the present application, the nickel source and the aluminum source also include the hydrates corresponding to the disclosed salts.

[0037] In the present application, the drying step in step 2) includes first evaporating the sol to obtain a transparent viscous sol, and then performing temperature increasing and stepwise drying on the transparent viscous sol.

[0038] In the present application, the evaporation operation is preferably evaporation of the solvent in a water bath at 80℃ for 8h; the temperature-rising stepwise drying is preferably drying at 100℃ for 12h, and then drying at 120℃ for 12h to obtain the xerogel.

[0039] In the present application, the xerogel is calcined after being ground.

[0040] In the present application, the calcination temperature in step 2) is 450-900℃, and can be specifically 500℃, 550℃, 600℃, 650℃, 700℃, 750℃, 800℃, 850℃; the calcination time is 1-3h, and can be specifically 1.2h, 1.5h, 1.8h, 2h, 2.2h, 2.5h, 2.8h.

[0041] In the present application, the reduction in step 3) includes reacting the catalyst intermediate product with hydrogen.

[0042] In the present application, the reduction temperature is 450-750℃, and can be specifically 500℃, 550℃, 600℃, 650℃, 700℃; the reduction time is 3-8h, and can be specifically 4h, 5h, 6h, 7h; the flow rate of hydrogen is 40-100mL / min, and can be specifically 50mL / min, 60mL / min, 70mL / min, 80mL / min, 90mL / min.

[0043] In the present application, the palladium source includes palladium acetate solution and / or palladium nitrate solution; the boron source includes ammonium borate solution.

[0044] In the present application, the mass ratio of the nickel / nickel-like aluminum spinel catalyst, palladium in the palladium source, and boron in the boron source is 100:0.002-0.005:0.8-1.5, preferably 100:0.003-0.004:0.9-1.2, and further preferably 100:0.003:1.

[0045] In the present application, the mixing of the nickel / nickel-like aluminum spinel catalyst, the palladium source, and the boron source is preferably mixing and drying the nickel / nickel-like aluminum spinel catalyst and the palladium source first, and then mixing the nickel / nickel-like aluminum spinel catalyst, the palladium source, and the boron source.

[0046] In the present application, the amount of the noble metal added is small, which ensures a relatively low preparation cost.

[0047] In the present application, the calcination temperature in step 4) is 350-420℃, and can be specifically 360℃, 370℃, 380℃, 390℃, 400℃, 410℃; the calcination time is 1-3h, and can be specifically 1.2h, 1.5h, 1.8h, 2h, 2.2h, 2.5h, 2.8h.

[0048] The application further provides the catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation, which is prepared by the preparation method.

[0049] In the application, the particle size of the catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation is 0.18-0.25 mm, and can be specifically 0.2 mm, 0.21 mm, 0.22 mm, 0.23 mm or 0.24 mm.

[0050] The application further provides application of the catalyst in preparing perhydrophenanthrene by phenanthrene hydrogenation.

[0051] The technical solutions in the embodiments of the application will be clearly and completely described below. Obviously, the described embodiments are only some of the embodiments of the application, but not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0052] Embodiment 1

[0053] First, the calculated amount (the molar ratio of Ni (NO3) 2·6H2O to Al (NO3) 3·9H2O is 1.45:2) of Ni (NO3) 2·6H2O, Al (NO3) 3·9H2O and C6H8O7·H2O (the molar ratio of citric acid to metal ions is 1:1) are dissolved in a certain amount of deionized water (the molar ratio of water to metal ions is 40:1) and stirred until completely dissolved. The solution is sealed and stirred for 3 hours to obtain a uniformly dispersed sol. The sol is placed in a 80℃ water bath and stirred to evaporate the solvent for 8 hours to obtain a transparent viscous gel. The gel is left to stand for 1 hour. The obtained gel is placed in a drying oven and dried in steps at 100℃ and 120℃ for 12 hours each to obtain a dry gel. Finally, the dry gel is ground into powder and heated to 750℃ at a rate of 1℃ / min in a muffle furnace and calcined for 2 hours to obtain a calcined catalyst. The calcined catalyst is reduced at 600℃ under H2 atmosphere (100mL / min) for 4 hours to obtain a nickel / nickel-like aluminum spinel catalyst.

[0054] The above nickel / nickel-like aluminum spinel catalyst is mixed with palladium acetate by stirring, dried, mixed with ammonium borate (the molar ratio of nickel / nickel-like aluminum spinel catalyst to effective palladium to effective boron is 100:0.003:1), and then dried under stirring. After drying, the catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation is obtained by calcining at 380℃ for 2.5 hours.

[0055] Embodiment 2

[0056] First, the calculated amount (Ni / Al molar ratio of 1.45:2) of Ni(NO3)2.6H2O, Al(NO3)3.9H2O and C6H8O7.H2O (molar ratio of citric acid to metal ions of 1:1) were dissolved in a certain amount of deionized water (molar ratio of water to metal ions of 40:1) and stirred until completely dissolved. The solution was sealed and stirred for 3 hours to obtain a uniformly dispersed sol. The sol was placed in a 80°C water bath and the solvent was evaporated by stirring for 8 hours to obtain a transparent viscous gel. The gel was left to stand for 1 hour. The obtained gel was placed in a drying oven and dried in steps at 100°C and 120°C for 12 hours each to obtain a dry gel. Finally, the dry gel was ground into powder and heated to 800°C at a rate of 1°C / min in a muffle furnace and calcined for 2 hours to obtain the calcined catalyst. The calcined catalyst was reduced under H2 atmosphere (100 mL / min) at 450°C for 7 hours to obtain the nickel / nickel-like aluminum spinel catalyst.

[0057] The above nickel / nickel-like aluminum spinel catalyst was mixed with palladium acetate and stirred, then mixed with ammonium borate after drying (nickel / nickel-like aluminum spinel catalyst: effective palladium: effective boron = 100:0.005:1), and then dried under stirring. After drying was completed, the catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation was obtained by calcining at 380°C for 2.5 hours.

[0058] Example 3

[0059] First, the calculated amount (Ni / Al molar ratio of 1.45:2) of Ni(NO3)2.6H2O, Al(NO3)3.9H2O and C6H8O7.H2O (molar ratio of citric acid to metal ions of 1:1) were dissolved in a certain amount of deionized water (molar ratio of water to metal ions of 40:1) and stirred until completely dissolved. The solution was sealed and stirred for 3 hours to obtain a uniformly dispersed sol. The sol was placed in a 80°C water bath and the solvent was evaporated by stirring for 8 hours to obtain a transparent viscous gel. The gel was left to stand for 1 hour. The obtained gel was placed in a drying oven and dried in steps at 100°C and 120°C for 12 hours each to obtain a dry gel. Finally, the dry gel was ground into powder and heated to 800°C at a rate of 1°C / min in a muffle furnace and calcined for 2 hours to obtain the calcined catalyst. The calcined catalyst was reduced under H2 atmosphere (100 mL / min) at 450°C for 7 hours to obtain the nickel / nickel-like aluminum spinel catalyst.

[0060] The above nickel / nickel-like aluminum spinel catalyst was mixed with palladium acetate and stirred, then mixed with ammonium borate after drying (nickel / nickel-like aluminum spinel catalyst: effective palladium: effective boron = 100:0.005:1), and then dried under stirring. After drying was completed, the catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation was obtained by calcining at 380°C for 2.5 hours.

[0061] Example 4

[0062] First, a calculated amount (Ni / Al molar ratio of 1.5:2) of Ni(NO3)2·6H2O, Al(CH3COO)3 and C6H8O7·H2O (citric acid / metal ion molar ratio of 0.8:1) were dissolved in a certain amount of deionized water (water / metal ion molar ratio of 25:1) and stirred until completely dissolved, sealed and stirred for 3 h, to obtain a uniformly dispersed sol; the sol was placed in a 80°C water bath and stirred to evaporate the solvent for 8 h, to obtain a transparent viscous gel, which was allowed to stand for 1 h; the obtained gel was placed in a drying oven and dried in steps, at 100°C and 120°C for 12 h each, to obtain a dry gel; finally, the obtained dry gel was ground into powder, heated to 850°C at 1°C / min in a muffle furnace and calcined for 1 h, to obtain a calcined catalyst. The calcined catalyst was reduced under H2 atmosphere (80 mL / min) at 450°C for 8 h, to obtain a nickel / nickel-like aluminum spinel catalyst.

[0063] The above nickel / nickel-like aluminum spinel catalyst was mixed with palladium acetate under stirring, dried, mixed with ammonium borate (nickel / nickel-like aluminum spinel catalyst: effective palladium: effective boron = 100:0.005:0.8), and then dried under stirring, and after drying was completed, calcined at 400°C for 1.5 h, to obtain a catalyst for the phegia hydrogenation of phenanthrene to perhydrophenanthrene.

[0064] Comparative Example 1

[0065] The difference between this comparative example and Example 1 is that no palladium and boron doping was performed.

[0066] Comparative Example 2

[0067] The difference between this comparative example and Example 1 is that no palladium doping was performed.

[0068] Experimental Example 1

[0069] The catalysts prepared in Example 1 and Comparative Examples 1-2 were evaluated. The catalyst evaluation reactor was a fixed bed. The catalyst particles were 0.2-0.25 mm in size. When the catalyst was loaded, to prevent local flashover during the reaction, 2 mL of quartz sand was mixed with the catalyst and loaded into the reaction tube, and 2 mL of quartz sand was filled above and below the mixed quartz sand and catalyst, to ensure that the catalyst was in the constant temperature zone of the reactor. The catalyst loading was 100 mg, and the catalyst was reduced in situ, with hydrogen as the reducing agent. The hydrogenation reaction conditions were 300°C, 5.0 MPa, and the H2 flow rate was set to 80 mL / min during the reaction. The raw material was 1 wt% phenanthrene / decalin feedstock at a flow rate of 10 mL / h (decalin as solvent), and the reaction time was set to 6 h. The phenanthrene conversion and perhydrophenanthrene selectivity at 1 h, 2 h, 3 h, 4 h, 5 h, and 6 h (i.e., the cumulative conversion or selectivity at a certain time) were tested for Example 1 and Comparative Examples 1-2. The test results are shown in Table 1:

[0070] Table 1 Catalyst evaluation results

[0071]

[0072] From Table 1, it can be seen that the catalyst for preparing perhydrophenanthrene by phenanthrene hydrogenation disclosed in the present application has excellent catalytic activity and perhydrophenanthrene selectivity. In Comparative Example 1, no palladium and boron are doped, resulting in a perhydrophenanthrene selectivity much lower than that in Example 1. In Comparative Example 2, palladium is doped, but when only palladium is doped, it is difficult to affect the catalytic performance of the active component, and the perhydrophenanthrene selectivity is also lower than that in Example 1, proving that there is a complex effect between palladium and boron in the present application. With the extension of the catalytic reaction time, the selectivity of Comparative Examples 1 and 2 shows a significant downward trend, while the catalyst prepared in Example 1 still has a phenanthrene conversion rate of 99.5% and a perhydrophenanthrene selectivity of 99.2% after 6h of catalysis, which reflects excellent stability and catalyst selectivity.

[0073] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0074] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a catalyst for the hydrogenation of phenanthrene to perhydrophenanthrene, characterized in that, Includes the following steps: 1) Mix nickel source, aluminum source, citric acid and water to obtain a sol; 2) The sol was dried and then calcined to obtain the catalyst intermediate; 3) Reduce the catalyst intermediate to obtain a nickel / nickel-aluminum spinel catalyst; 4) The nickel / nickel-aluminum spinel catalyst was mixed with a palladium source and a boron source, dried and then calcined to obtain a catalyst for the hydrogenation of phenanthrene to perhydrophenanthrene. The mass ratio of the nickel / nickel-aluminum spinel catalyst to palladium in the palladium source and boron in the boron source is 100:0.002~0.005:0.8~1.

5.

2. The method for preparing a catalyst for the hydrogenation of phenanthrene to perhydrophenanthrene according to claim 1, characterized in that, In step 1), the molar ratio of nickel in the nickel source to aluminum in the aluminum source is 1.2~1.5:2; the total molar ratio of nickel in the nickel source and aluminum in the aluminum source to the molar ratio of citric acid and water is 1:0.1~3:20~70. The nickel source includes nickel nitrate and / or nickel acetate; the aluminum source includes aluminum nitrate and / or aluminum acetate.

3. The method for preparing a catalyst for the hydrogenation of phenanthrene to perhydrophenanthrene according to claim 2, characterized in that, In step 2), the roasting temperature is 450~900℃ and the roasting time is 1~3h.

4. A method for preparing a catalyst for the hydrogenation of phenanthrene to perhydrophenanthrene according to any one of claims 1 to 3, characterized in that, The reduction in step 3) includes reducing the catalyst intermediate by reacting it with hydrogen.

5. The method for preparing a catalyst for the hydrogenation of phenanthrene to perhydrophenanthrene according to claim 4, characterized in that, The reduction temperature is 450~750℃, the reduction time is 3~8h, and the hydrogen flow rate is 40~100mL / min.

6. The method for preparing a catalyst for the hydrogenation of phenanthrene to perhydrophenanthrene according to claim 5, characterized in that, The palladium source includes palladium acetate solution and / or palladium nitrate solution; the boron source includes ammonium borate solution.

7. The method for preparing a catalyst for the hydrogenation of phenanthrene to perhydrophenanthrene according to claim 1, characterized in that, The roasting temperature in step 4) is 350~420℃, and the roasting time is 1~3h.

8. The catalyst for the hydrogenation of phenanthrene to perhydrophenanthrene prepared by the preparation method according to any one of claims 1 to 7.

9. The application of the catalyst according to claim 8 in the hydrogenation of phenanthrene to produce all-hydrophenanthrene.

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