Bimetallic pd-zr / cn catalysts, their preparation and use in hydrogenation sulfur tolerant systems

Abstract

The application discloses a bimetallic Pd-Zr / CN catalyst, a preparation method thereof and application of the bimetallic Pd-Zr / CN catalyst in a hydrogenation anti-sulfur system. The preparation method of the bimetallic Pd-Zr / CN catalyst comprises the following steps: 1) respectively preparing a Pd precursor aqueous solution and a Zr precursor solution; 2) preparing a CN carrier; 3) preparing Zr / CN; and 4) preparing the bimetallic Pd-Zr / CN catalyst. The application provides application of the bimetallic Pd-Zr / CN catalyst in a hydrogenation anti-sulfur system of unsaturated alkene compounds or aromatic nitro compounds, and the bimetallic Pd-Zr / CN catalyst exhibits good catalytic activity and stability.

Description

Technical Field

[0001] This invention relates to the field of catalyst preparation technology, specifically to a bimetallic Pd-Zr / CN catalyst, its preparation method, and its application in hydrogenation antisulfurization systems for unsaturated alkene compounds or aromatic nitro compounds. Background Technology

[0002] Gasoline cracking processes contain a large amount of aromatics, such as benzene, toluene, and xylene (BTX), as well as unsaturated compounds, such as dienes and styrene. To ensure the stability of subsequent downstream processes, PyGas must be hydrotreated to serve as a high-octane additive in the gasoline pool. However, cracked gas typically contains varying levels of sulfur and nitrogen compounds, so the selective hydrotreating catalyst must possess strong resistance to poisoning.

[0003] Sulfur poisoning deactivation is particularly severe in noble metal-supported catalysts and has been extensively studied. One of the main problems with palladium is its high sensitivity to sulfur compounds commonly present in hydrogenation feedstocks. Therefore, improving the activity and sulfur resistance of noble metal catalysts is an important issue that urgently needs to be addressed. High intrinsic hydrogenation activity and sulfur resistance can be enhanced by altering the physicochemical properties of the metal atoms in the following ways: (i) changing the acid-base properties of the support; (ii) changing the electronic and structural properties of the metal particles by adding a second metal; or (iii) alloying.

[0004] In the 1980s, it was thought that adding a second metal might be an effective way to improve palladium’s reactivity and sulfur resistance in these reactions. The addition of a second metal could involve simple effects, such as helping to reduce the first metal or enhancing hydrogen spillover, or it could involve complex metal-metal interactions (geometric effects, electronic effects, stabilizing effects, synergistic effects, the emergence of bifunctional mechanisms).

[0005] Furthermore, while there is extensive research on additives both domestically and internationally, few studies have investigated the role of Zr in selective hydrogenation and sulfur resistance. Therefore, it is essential to study the influence of Zr on the noble metal Pd and to prepare catalysts with high sulfur resistance. Summary of the Invention

[0006] In view of the problems existing in the prior art, the purpose of this invention is to provide a bimetallic Pd-Zr / CN catalyst, its preparation method, and its application in hydrogenation antisulfurization systems of unsaturated alkene compounds or aromatic nitro compounds.

[0007] In a first aspect, the present invention provides a method for preparing a bimetallic Pd-Zr / CN catalyst, comprising the following steps:

[0008] 1) Prepare aqueous solutions of Pd precursor and Zr precursor solutions respectively;

[0009] 2) Activated carbon and the N precursor are dispersed in deionized water, ultrasonically treated for 1-2 hours, filtered, washed, and dried to obtain the CN support. The activated carbon and the N precursor are added according to a ratio to achieve a theoretical N content of 2-5 wt% in the CN support. The theoretical N content = m N / (m N +m 活性炭 )×100%, where m N This represents the mass of nitrogen contained in the precursor of nitrogen.

[0010] 3) Mix CN carrier and ethanol, stir to form a slurry, then slowly add Zr precursor solution, sonicate for 0-60 min, stir at 40-70℃ for 12-24 h, centrifuge and dry to obtain Zr / CN;

[0011] 4) Add the Zr / CN obtained in step 3) to deionized water and stir until homogeneous to form a slurry. Introduce the Pd precursor solution prepared in step 1) into the slurry, sonicate for 0-60 min, stir at 40-70℃ for 12-24 h, adjust the pH to 8-10 with alkaline solution, then precipitate and age for 2-3 h, add reducing agent for reduction, filter after reduction, wash thoroughly with deionized water, and finally dry to directly obtain the bimetallic Pd-Zr / CN catalyst.

[0012] The CN support, Zr precursor, and Pd precursor are fed in such a manner that the theoretical Zr content in the bimetallic Pd-Zr / CN catalyst is 10-30 wt% and the theoretical Pd content is 4-5 wt%, respectively. The theoretical Zr content = m Zr / (m CN载体 +m Pd +m ZrO2 )×100%, Theoretical content of Pd = m Pd / (m CN载体 +m Pd +m ZrO2 )×100%, where m Pd m represents the mass of Pd contained in the Pd precursor. ZrO2 This represents the mass of ZrO2 calculated based on the mass of Zr contained in the Zr precursor.

[0013] Preferably, the precursor of Pd is palladium chloride, palladium acetate, or palladium nitrate.

[0014] Preferably, the precursor of N is at least one of urea, melamine, and dicyandiamide.

[0015] Preferably, the Zr precursor is at least one of zirconium n-propoxide, zirconium oxychloride, zirconium nitrate pentahydrate, and zirconium chloride.

[0016] Preferably, in step 2), the theoretical N content in the CN carrier is 5 wt%.

[0017] Preferably, in steps 3) and 4), the ultrasound time is 30 min.

[0018] Preferably, in step 2), the drying conditions are: vacuum drying at 50-120℃ for 6-12 hours.

[0019] Preferably, in step 3), the drying conditions are: drying at 100-120℃ for 7-9 hours.

[0020] Preferably, the alkaline solution is a sodium hydroxide solution, a sodium carbonate solution, a potassium hydroxide solution, or an ammonia solution.

[0021] Preferably, in step 4), the reducing agent is hydrazine hydrate, formaldehyde, hydrogen peroxide, or sodium borohydride, more preferably sodium borohydride. The molar amount of the reducing agent is 10-20 times the molar amount of Pd. The reduction conditions are: 50-80℃ water bath heating at 400-500 r·min. -1 Stir for 1-3 hours.

[0022] Preferably, in step 4), the drying conditions are: drying at 100-120℃ for 7-9 hours.

[0023] In a second aspect, the present invention provides a bimetallic Pd-Zr / CN catalyst prepared according to the preparation method described in the first aspect.

[0024] The third invention provides the application of the bimetallic Pd-Zr / CN catalyst in hydrogenation antisulfurization systems for unsaturated alkenes or aromatic nitro compounds.

[0025] The application specifically includes the following steps:

[0026] Unsaturated alkene compounds or aromatic nitro compounds, bimetallic Pd-Zr / CN catalyst powder, and solvent are added to a reactor, and a continuous hydrogenation reaction is carried out under a hydrogen atmosphere to generate hydrogenation products; the unsaturated alkene compounds or aromatic nitro compounds contain sulfur-containing impurities.

[0027] In this invention, the range of unsaturated olefin compounds and aromatic nitro compounds is broad. The unsaturated olefin compounds can be styrene, p-methylstyrene, norbornene, 2-[b-(2-thienyl)vinyl]benzoic acid, etc., whose unsaturated double bonds are reduced to single bonds by catalytic hydrogenation. The aromatic nitro compounds can be 4-nitroanisole, 2-nitrodiphenyl sulfide, etc., whose nitro groups are reduced to amino groups by catalytic hydrogenation. The sulfur-containing impurities are organic sulfides, such as at least one of thiophene, dibenzothiophene, n-dodecyl mercaptan, ethyl sulfide, diethyl disulfide, etc.

[0028] In this invention, the solvent is at least one selected from methanol, ethanol, toluene, dioxane, and N,N-dimethylformamide.

[0029] In this invention, the hydrogenation reaction temperature is 70-150°C. When the unsaturated alkene compound is p-methylstyrene, the hydrogenation reaction temperature is 70-100°C, preferably 80-90°C, and more preferably 80°C.

[0030] In this invention, the hydrogenation reaction pressure is 0.8-3 MPa. When the unsaturated alkene compound is p-methylstyrene, the hydrogenation reaction pressure is 0.8-1.5 MPa, preferably 1-1.2 MPa, and more preferably 1 MPa.

[0031] In this invention, the hydrogenation reaction is carried out under stirring conditions, with the stirring rate controlled at 800-1000 r·min. -1 .

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] 1) This invention first prepares N-doped activated carbon as a support for a bimetallic catalyst, then coats the CN surface with ZrO2, and finally loads the Pd precursor onto the Zr / CN, which allows the noble metal to be better anchored on the catalyst and has better dispersion. Since the Zr species exist on the catalyst in the form of ZrO2, acidic sites are generated on the catalyst surface. Furthermore, the transfer of hydrogen gas from the active metal Pd to ZrO2 causes Zr(Ⅳ) to become Zr(Ⅲ), resulting in oxygen vacancies on the support surface. The synergistic effect of the acidic sites and oxygen vacancies improves the catalyst's sulfur resistance. Moreover, due to electronic effects, both Zr and N act as electron donors, donating electrons to Pd, leading to the generation of more active Pd species. 0 Therefore, the catalyst activity is significantly improved. In summary, the bimetallic catalyst prepared by this invention can resist sulfur while maintaining hydrogenation activity.

[0034] 2) By adopting the technical solution of the present invention, N and Zr are introduced into the catalyst support to make the noble metal Pd nanoparticles more dispersed and smaller in size. Under the action of N and Zr, Pd NPs are more easily anchored on the support, which greatly enhances the stability of metal NPs.

[0035] 3) Compared with traditional supported noble metal catalysts, this invention introduces a second metal, Zr, during the catalyst preparation process. Since Zr's electronegativity of 1.3 is much lower than Pd's electronegativity of 2.2, Zr acts as an electron donor, providing electrons to the Pd species, thus preventing Pd from becoming electron-bearing. 0 The significantly increased content of [agent] enhances its ability to dissociate H2, thus increasing its activity in the reaction system.

[0036] 4) Compared with conventional activated carbon-supported noble metal catalysts, the catalyst of the present invention introduces a second metal, Zr, which introduces abundant acidic sites on the support surface, thereby reducing the strength of Me-S, effectively reducing S poisoning and deactivation, and greatly improving the stability of the catalyst.

[0037] 5) The bimetallic Pd-Zr / CN catalyst provided by this invention exhibits good catalytic activity and stability in the hydrogenation reaction of unsaturated alkenes or aromatic nitro compounds. Attached Figure Description

[0038] Figure 1 (a) and (b) are TEM images of the Pd / CN catalyst prepared in Comparative Example 1, where (a) represents the fresh catalyst and (b) represents the catalyst used three times; (c) and (d) are TEM images of the Pd1-Zr5 / CN5 catalyst prepared in Example 1, where (c) represents the fresh catalyst and (d) represents the catalyst used ten times; (e) is an elemental mapping diagram of the fresh catalyst prepared in Example 1; (f) is an HRTEM image, lattice fringes and diffraction pattern of the fresh catalyst prepared in Example 1; (h) is an elemental mapping diagram of the Pd1-Zr5 / CN5 catalyst prepared in Example 1 after 10 uses; (g) is the elemental content of the fresh Pd1-Zr5 / CN5 catalyst prepared in Example 1 as determined by EDS. Figure 1 Transmission electron microscopy (TEM) has preliminarily revealed the morphological distribution of the catalyst. Figure 1 (f) High-resolution transmission electron microscopy (HR-TEM) shows the lattice fringes around Pd NPs with a spacing of 0.23 nm, and the corresponding SAED (selected area electron diffraction) pattern corresponding to the (111) crystal plane of Pd. Figure 1(e) In the mapping diagram, the orange particles are metal Pd NPs, and the purple particles are metal Zr NPs. This indicates that Pd and Zr have been successfully loaded into the catalyst. Furthermore, observation and particle size analysis show that after the introduction of the second metal Zr, the Pd nanoparticles are more uniformly dispersed, with a smaller particle size and an average particle size of only 2.65 nm. Figure 1 (c)), while the catalyst doped only with N also exhibits good dispersibility, its average particle size is still larger than that of the catalyst with Zr, with an average particle size of approximately 3.25 nm. Figure 1 (a)). TEM images of used catalysts, such as... Figure 1 As shown in (b) and (d), the single metal Pd / CN exhibits severe agglomeration and larger particle size, while the catalyst prepared by introducing a second metal Zr shows little change.

[0039] Figure 2 The images show the H2-TPD-MS diagrams of the catalysts prepared in Examples 1-3 and Comparative Example 1. Figure 2 The results show that for the Pd-free sample (Zr / CN), no H2 desorption peaks were observed under both H2 adsorption and non-H2 adsorption conditions. The appearance of an unstable peak starting at 450℃ can be attributed to hydrogen evolution from some oxygen-containing functional groups on the catalyst support. The pristine Pd / CN exhibited two desorption peaks, centered at ~137℃ and ~358℃. The former is attributed to weakly adsorbed hydrogen, and the latter to strongly chemisorbed hydrogen, such as adsorbed hydrogen in the Pd subsurface or adsorbed hydrogen at the metal-support interface. For Pd-Zr / CN (Pd:Zr = 1:3, 1:5, 1:7), all samples showed similar desorption peaks in the temperature range of 390-425℃. The desorption temperature increased with increasing Zr content, indicating that the catalyst activity increased. When the Pd:Zr molar ratio reached 1:7, the desorption temperature no longer changed, indicating that the activity had reached its maximum. The peak intensities of all Zr-introduced catalysts were much higher than those of Pd / CN, indicating that hydrogen overflowed onto these catalysts.

[0040] Figure 3 These are NH3-TPD diagrams of the catalysts prepared in Examples 1-3 and Comparative Example 1. The total concentration and intensity of acid sites on the bimetallic catalysts were determined by NH3-TPD. Figure 3 As shown, pure Pd / CN mainly contains weak acids. The introduction of Zr increases the number of acidic sites in the catalyst, and the amount of strong acids gradually increases with the addition of Zr content.

[0041] Figure 4The images show the XRD patterns of Pd-Zr / CN catalysts prepared at different calcination temperatures in Examples 1 and Comparative Examples 8-12 (with a Pd to Zr molar ratio of 1:5). The black lines in the XRD patterns do not represent any Zr diffraction peaks; only a diffuse peak appears at 2θ = 30°, without a clear crystalline phase. Therefore, we consider the ZrO2 on the catalyst to be amorphous. The peaks at 2θ = 30.2, 35.0, 50.4, and 60.0° in the calcined catalyst are easily attributed to tetragonal ZrO2 (t-ZrO2) (PDF#03-0640), while the peaks at 2θ = 17.4, 24.1, 27.9, 31.4, 34.1, 38.4, 40.4, 45.1, 55.3, 56.8, 57.9, 59.6, and 65.2° are attributed to monoclinic ZrO2 (m-ZrO2) (PDF#01-0750). With increasing calcination temperature, ZrO2 changes from amorphous to tetragonal and then to monoclinic ZrO2.

[0042] Figure 5 The XRD patterns of the fresh Pd / CN catalyst prepared in Comparative Example 1, the Pd / CN catalyst after three uses, and the fresh Pd-Zr / CN catalyst in Example 1 after ten uses (the molar ratio of Pd to Zr is 1:5) are shown. It can be seen that the bimetallic Pd-Zr / CN catalyst, after 10 uses, only shows a weak diffraction peak at 2θ = 40.114°, while the monometallic Pd / CN catalyst, after three uses, shows obvious diffraction peaks at 2θ = 40.114, 46.658, and 68.118°. This indicates that the monometallic catalyst underwent significant agglomeration, while the bimetallic catalyst still exhibits high dispersion, consistent with the TEM results.

[0043] Figure 6 This is a stability evaluation diagram of the Pd1-Zr5 / CN5 catalyst prepared in Example 1. It can be seen that no significant decrease in catalyst performance was observed during 10 trials; the conversion rate to methylstyrene remained stable at 99.9%, and the selectivity was around 99.0%.

[0044] Figure 7The XPS spectra of the catalysts prepared in Examples 1-3 and Comparative Example 1 are shown below. (a), (b), (c), and (d) are XPS spectra of Pd, Zr, O, and N in the fresh catalyst; (e) is the XPS spectra of S after ten uses in Example 1 and three uses in Comparative Example 1; and (f) is the full spectrum of Example 1. The chemical states of each element in the catalyst were determined by XPS and corrected using C1s (BE = 284.8 eV). The XPS spectrum of Pd 3d is shown in Figure (a). The asymmetric Pd 3d XPS spectrum can be decomposed into six peaks. The components with binding energies of 335.6 eV and 341 eV, and the components with binding energies of 336.8 eV and 342.0 eV, are attributed to the more active Pd. 0 and Pd with a small amount of adsorbed oxygen 2+ The species, and the peaks at binding energies of 338.0 eV and 343.3 eV, belong to the surface Pd in ​​a high oxidation state. ε+ Species, (2 < ε < 4). From the XPS plot of Pd 3d, we can clearly see that with the introduction of Zr, Pd shifts towards lower binding energies, indicating an increase in the number of active Pd species in lower valence states. Simultaneously, the introduction of Zr causes overlap between the Pd 3d and Zr 3p orbitals, with observed Zr 3p³ / 2 peaks at 334.1 eV and Zr 3p⁵ / 2 peaks at 346.6 eV, indicating a strong interaction between Pd and ZrO₂. Since the electronegativity of Zr (1.3) is much lower than that of Pd (2.2), Pd more readily gains electrons to generate highly active Pd species. 0 This also explains the main reason for the shift in the Pd 3d XPS spectrum towards lower binding energies. To further verify the electronic effects between Pd and Zr, we also performed Zr 3d XPS measurements, and the results are shown in Figure (c). The two valence states of Zr in all catalysts were separated in the Zr 3d spectrum. In the catalyst without active metal Pd, the binding energy peak of Zr 3d5 / 2 was [missing value]. 3+ Approximately 181.5 eV, Zr 4+ Approximately 182.2 eV, Zr 4+ Lattice ions derived from ZrO2, while Zr 3+ ZrO2 originates from partially hypoxic conditions. Zr is calculated based on peak area. 3+ / (Zr 3+ +Zr 4+The ratio reflects the density of oxygen vacancies on the ZrO2 surface. The peaks of Zr species in the bimetallic catalyst shift to higher binding energies, further confirming the transfer of electrons from Zr to Pd. The XPS data for N 1s are shown in Figure (d). The peaks at binding energies of 398.3 eV, 400.3 eV, and 401.5 eV are attributed to pyridine N (Np), pyrrole N (Nl), and graphitic N (Ng), respectively. According to literature reports, graphitic N (Ng) may contribute to nucleation and dispersion, while pyridine N (Np) acts as both an anchoring agent and a dispersant. Furthermore, there is an electronic effect between the N species and the active species Pd, thus shifting the binding energy of N towards the positive direction. Each O 1s XPS spectrum (b) can be decomposed into three components at BE = 530.8 eV, 532.0 eV, and 533.4 eV, which are attributed to lattice oxygen O, respectively. 2- The high oxygen vacancy concentration in the Pd-Zr metal catalyst is likely due to the strong interaction between Pd and the doped metal, and secondly, the presence of hydrogen spillover, which allows hydrogen to migrate to Zr after dissociation by the active metal Pd, causing Zr(Ⅳ) to lose lattice oxygen (O). 2- The Pd-to-Zr group transforms into Zr(III), creating oxygen vacancies. Therefore, the Oβ peak area of ​​the bimetallic catalyst is relatively large, with the oxygen-deficient region reaching 50.21% when the molar ratio of Pd to Zr is 1:5, consistent with the Zr 3d XPS results. It can be concluded that for the bicomponent catalyst, the binding energy of Pd 3d shifts to lower binding energies, while the binding energies of Zr 3d and N1s shift to higher binding energies. This indicates that electrons transfer from Zr and N to the highly electronegative Pd atoms. From S2p XPS(e), we found that the monometallic catalyst adsorbs more low-valence S species, while the bimetallic catalyst adsorbs more high-valence sulfur species. According to literature, the sulfur toxicity efficiency to metals is: SO42-... 2- <SO2<H2S. Therefore, the lower valence state of S is more toxic and more likely to deactivate catalysts, while the higher valence state of sulfur is less toxic, combines with metals to form sulfate species, and can be desorbed in hot air. Detailed Implementation

[0045] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the scope described.

[0046] Example 1

[0047] 1. A method for preparing a bimetallic catalyst:

[0048] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a Pd concentration of 0.05 g·mL⁻¹. -1The Pd precursor solution was left to stand until it was ready for use.

[0049] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0050] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0051] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% n-propoxide zirconium in n-propanol solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0052] 5) Dry the solution obtained in step 4) at 110°C for 8 hours in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0053] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0054] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr5 / CN5-3 catalyst.

[0055] The prepared catalyst 1 was analyzed. ICP-MS results showed that the loading of Pd was 4.26 wt% and the loading of Zr was 20.56 wt%. XRD showed that ZrO2 was amorphous and Pd was relatively uniformly dispersed. TEM results showed that the average particle size of Pd NPs was 2.35 nm. NH3-TPD showed that there were 3 acidic sites.

[0056] 2. Application of Catalyst 1 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0057] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 2.

[0058] Example 2

[0059] 1. A method for preparing a bimetallic catalyst:

[0060] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0061] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0062] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0063] 4) Place 1.64 g of CN carrier from step 3) in a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 1.24 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0064] 5) Dry the solution obtained in step 4) at 110°C for 8 hours in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0065] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0066] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr3 / CN5-3 catalyst.

[0067] 2. Application of catalyst 2 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0068] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr3 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 2.

[0069] Example 3

[0070] 1. A method for preparing a catalyst:

[0071] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0072] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0073] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0074] 4) Place 1.3g of CN carrier from step 3) in a beaker, add 50mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.91mL of 70wt% zirconium propoxide solution to the slurry, then sonicate for 30min and stir at 60℃ for 12h.

[0075] 5) Dry the solution obtained in step 4) at 110°C for 8 hours in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0076] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0077] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr7 / CN5-3 catalyst.

[0078] 2. Application of catalyst 3 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0079] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr7 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 2.

[0080] Example 4

[0081] 1. A method for preparing a catalyst:

[0082] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0083] 2) Take 0.085g of urea and 1.96g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0084] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0085] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0086] 5) Dry the solution obtained in step 4) at 110°C for 8 hours in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0087] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0088] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr5 / CN2-3 catalyst.

[0089] 2. Application of catalyst 4 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0090] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN2-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 3.

[0091] Example 5

[0092] 1. A method for preparing a catalyst:

[0093] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0094] 2) Take 0.13g of urea and 1.94g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0095] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0096] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0097] 5) Dry the solution obtained in step 4) at 110°C for 8 hours in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0098] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0099] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr5 / CN3-3 catalyst.

[0100] 2. Application of Catalyst 5 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0101] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN3-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 3.

[0102] Example 6

[0103] 1. A method for preparing a catalyst:

[0104] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0105] 2) Take 0.17g of urea and 1.92g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0106] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0107] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0108] 5) Dry the solution obtained in step 4) at 110°C for 8 hours in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0109] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0110] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr5 / CN4-3 catalyst.

[0111] 2. Application of Catalyst 6 in the selective catalytic hydrogenation and desulfurization of p-methylstyrene:

[0112] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN4-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 3.

[0113] Example 7

[0114] 1. A method for preparing a catalyst:

[0115] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0116] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0117] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0118] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 10 min and stir at 60 °C for 12 h.

[0119] 5) Dry the solution obtained in step 4) at 110°C for 8 hours in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 10 min and stir at 60°C for 12 h.

[0120] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0121] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr5 / CN5-1 catalyst.

[0122] 2. Application of Catalyst 7 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0123] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5-1 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 4.

[0124] Example 8

[0125] 1. A method for preparing a catalyst:

[0126] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0127] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0128] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0129] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 60 min and stir at 60 °C for 12 h.

[0130] 5) Dry the solution obtained in step 4) at 110°C for 8 hours in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 60 min and stir at 60°C for 12 h.

[0131] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0132] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr5 / CN5-6 catalyst.

[0133] 2. Application of Catalyst 8 in the selective catalytic hydrogenation and desulfurization of p-methylstyrene:

[0134] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5-6 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 4.

[0135] A comparison of application conditions was made for catalyst 1 prepared in Example 1:

[0136] Example 9

[0137] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 70 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 8.

[0138] Example 10

[0139] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 90 °C, with the mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 8.

[0140] Example 11

[0141] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 100 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 8.

[0142] Example 12

[0143] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 0.8 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 7.

[0144] Example 13

[0145] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1.2 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 7.

[0146] Example 14

[0147] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1.5 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 7.

[0148] Example 15

[0149] 0.08 mol of 2-[b-(2-thienyl)vinyl]benzoic acid and 5 wt% Pd1-Zr5 / CN5-3 catalyst were added to a 250 mL reactor, followed by the addition of 80 mL of DMF. The reactor was then repeatedly purged with N2 to check its airtightness. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 1.

[0150] Example 16

[0151] 0.08 mol of 4-nitroanisole and 5 wt% Pd1-Zr5 / CN5-3 catalyst were added to a 250 mL reactor, followed by 80 mL of toluene. The reactor was then repeatedly purged with N2 to check its airtightness. The reaction was carried out at 150 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 3 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 1.

[0152] Example 17

[0153] 0.08 mol norbornene and 5 wt% Pd1-Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, and 80 mL of 1,4-dioxane was added and mixed. Then, 2500 ppm n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 100 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 1.

[0154] Example 18

[0155] 0.08 mol of 2-nitrodiphenyl sulfide and 5 wt% Pd1-Zr5 / CN5-3 catalyst were added to a 250 mL reactor, followed by the addition of 80 mL of toluene. The reactor was then repeatedly purged with N2 to check its airtightness. The reaction was carried out at 150 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 3 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 1.

[0156] Table 1. Expansion of Pd1-Zr5 / CN5-3 in different reaction systems

[0157]

[0158] Example 19

[0159] The reaction conditions and feed ratios were kept consistent with those in Example 1. The reacted catalysts 1-8 were placed in a 250 mL reactor. When the conversion rate of p-methylstyrene reached 20%, the catalytic reaction time was recorded, and the reaction was repeated five times. The hydrogenation products were quantitatively analyzed using an Anglient 7890B gas chromatograph. The results are shown in Table 8.

[0160] Comparative Example 1

[0161] 1. A method for preparing a catalyst:

[0162] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0163] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0164] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0165] 4) Place the 1.9g CN carrier from step 3) into a beaker, add 60mL of deionized water to form a slurry, introduce the 2mL precursor solution prepared in step 1) into the slurry, then sonicate for 30min and stir at 60℃ for 12h.

[0166] 5) After soaking for 12 hours in step 4), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, reduce it with 20 times the molar amount of Pd NaBH4, finally filter and wash with deionized water to neutralize.

[0167] 6) Dry the filter cake obtained in step 5) in a drying oven at 110℃ for 8 hours, and finally grind it into powder to obtain the bimetallic Pd / CN5-3 catalyst.

[0168] 2. Application of Catalyst 9 in the selective catalytic hydrogenation and desulfurization of p-methylstyrene:

[0169] 0.08 mol of p-methylstyrene and 5 wt% Pd / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 2.

[0170] Comparative Example 2

[0171] 1. A method for preparing a catalyst:

[0172] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0173] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0174] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0175] 4) Place 1.04 g of CN carrier from step 3) in a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 4.16 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0176] 5) Dry the solution obtained in step 4) at 110°C in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0177] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0178] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr. 10 / CN5-3 catalyst.

[0179] 2. Application of Catalyst 10 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0180] Take 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr 10The CN5-3 catalyst was added to a 250 mL reactor along with 80 mL of toluene, followed by the addition of 2500 ppm n-dodecyl mercaptan. The reactor was then repeatedly purged with nitrogen (N2) to check its airtightness. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 rpm. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 2.

[0181] Table 2. Effect of different Zr loadings on catalyst performance

[0182]

[0183]

[0184] Comparative Example 3

[0185] 1. A method for preparing a catalyst:

[0186] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0187] 2) Place 1.47g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) carrier in a beaker, add 50mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08mL of 70wt% zirconium propoxide solution to the slurry, then sonicate for 30min and stir at 60℃ for 12h.

[0188] 3) Dry the solution obtained in step 2) at 110°C in a forced-air drying oven, then add 60 mL of deionized water to form a slurry, introduce 2 mL of Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0189] 4) After soaking for 12 hours in step 3), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0190] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr5 / C-3 catalyst.

[0191] 2. Application of Catalyst 11 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0192] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / C-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 3.

[0193] Comparative Example 4

[0194] 1. A method for preparing a catalyst:

[0195] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0196] 2) Take 0.34g of urea and 1.84g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0197] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0198] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0199] 5) Dry the solution obtained in step 4) at 110°C in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0200] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0201] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr5 / CN8-3 catalyst.

[0202] 2. Application of Catalyst 12 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0203] Take 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr 15 The CN8-3 catalyst was added to a 250 mL reactor along with 80 mL of toluene, followed by the addition of 2500 ppm n-dodecyl mercaptan. The reactor was then repeatedly purged with nitrogen (N2) to check its airtightness. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 rpm. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 3.

[0204] Table 3. Effect of different theoretical N contents on catalyst performance

[0205]

[0206] Comparative Example 5

[0207] 1. A method for preparing a catalyst:

[0208] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0209] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0210] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0211] 4) Place 1.47g of CN carrier from step 3) into a beaker, add 50mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08mL of 70wt% zirconium propoxide solution to the slurry. Stir at 60℃ for 12h without sonication.

[0212] 5) Dry the solution obtained in step 4) at 110°C in a forced-air drying oven, then add 60mL of deionized water to form a slurry. Introduce the 2mL Pd precursor solution prepared in step 1) into the slurry and stir at 60°C for 12h without sonication.

[0213] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0214] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1-Zr5 / CN5 catalyst.

[0215] 2. Application of Catalyst 13 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0216] 0.08 mol of p-methylstyrene and 5 wt% Pd1-Zr5 / CN5 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 4.

[0217] Table 4. Effect of ultrasonic preparation on catalyst performance

[0218]

[0219] Comparative Example 6 (Co-impregnation)

[0220] 1. A method for preparing a catalyst:

[0221] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0222] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0223] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0224] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution and 2 mL of precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0225] 5) After soaking for 12 hours as in step 4), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd using NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0226] 6) Dry the filter cake obtained in step 5) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Pd1Zr5 / CN5-3 catalyst.

[0227] 2. Application of Catalyst 14 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0228] 0.08 mol of p-methylstyrene and Pd1Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 5.

[0229] Comparative Example 7 (Pd impregnated first, then Zr impregnated)

[0230] 1. A method for preparing a catalyst:

[0231] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0232] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0233] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0234] 4) Place 1.47g of CN carrier from step 3) into a beaker, add 50mL of deionized water, and after stirring to form a slurry, slowly add 2mL of precursor solution prepared in step 1) into the slurry, then sonicate for 30min and stir at 60℃ for 12h.

[0235] 5) After soaking for 12 hours in step 4), adjust the pH to 8-10 with 1 mol / L NaOH solution, then age for 2 hours, and finally filter and wash with deionized water to neutralize.

[0236] 6) The filter cake obtained in step 5) is dried in a 110℃ forced-air drying oven for 8 hours, then dissolved in 60 mL of anhydrous ethanol. After stirring to form a slurry, 2.08 mL of 70 wt% zirconium propoxide solution is slowly added dropwise to the slurry, followed by sonication for 30 min and stirring at 60℃ for 12 h. The pH is adjusted to 10 with 1 mol / L NaOH solution, then aged for 2 h, and then reduced with 20 times the molar amount of Pd using NaBH4. The reduction is carried out under 60℃ water bath heating conditions at 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0237] 7) Dry the filter cake obtained in step 6) in a 110℃ forced-air drying oven for 8 hours, and finally grind it into powder to obtain the bimetallic Zr5-Pd1 / CN5-3 catalyst.

[0238] 2. Application of Catalyst 15 in the selective catalytic hydrogenation and desulfurization of p-methylstyrene:

[0239] 0.08 mol of p-methylstyrene and Pd1Zr5 / CN5-3 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 5.

[0240] Table 5. Effects of different preparation methods on reaction performance

[0241]

[0242] Comparative Example 8

[0243] 1. A method for preparing a catalyst:

[0244] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0245] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0246] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0247] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0248] 5) Dry the solution obtained in step 4) at 110°C in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0249] 6) After soaking for 12 hours as in step 5), adjust the pH to 8-10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0250] 7) The filter cake obtained in step 6) was dried in a 110℃ forced-air drying oven for 8 hours, and finally ground into powder. The powder was heated from room temperature to 300℃ at 5℃ / min in a tube furnace under N2 atmosphere and held for 3 hours. After natural cooling to room temperature, the resulting catalyst was calculated as Pd1-Zr5 / CN5-300.

[0251] 2. Application of Catalyst 16 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0252] 0.08 mol of p-methylstyrene and Pd1-Zr5 / CN5-300 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 6.

[0253] Comparative Example 9

[0254] 1. A method for preparing a catalyst:

[0255] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0256] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0257] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0258] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0259] 5) Dry the solution obtained in step 4) at 110°C in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0260] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0261] 7) The filter cake obtained in step 6) was dried in a 110℃ forced-air drying oven for 8 hours, and finally ground into powder. The powder was heated from room temperature to 450℃ at 5℃ / min in a tube furnace under N2 atmosphere and held for 3 hours. After natural cooling to room temperature, the resulting catalyst was Pd1-Zr5 / CN5-450.

[0262] 2. Application of Catalyst 17 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0263] 0.08 mol of p-methylstyrene and Pd1-Zr5 / CN5-450 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 6.

[0264] Comparative Example 10

[0265] 1. A method for preparing a catalyst:

[0266] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0267] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0268] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0269] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0270] 5) Dry the solution obtained in step 4) at 110°C in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0271] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0272] 7) The filter cake obtained in step 6) was dried in a 110℃ forced-air drying oven for 8 hours, and finally ground into powder. The powder was heated from room temperature to 600℃ at 5℃ / min in a tube furnace under N2 atmosphere and held for 3 hours. After natural cooling to room temperature, the resulting catalyst was Pd1-Zr5 / CN5-600.

[0273] 2. Application of Catalyst 18 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0274] 0.08 mol of p-methylstyrene and Pd1-Zr5 / CN5-600 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 6.

[0275] Comparative Example 11

[0276] 1. A method for preparing a catalyst:

[0277] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0278] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0279] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0280] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0281] 5) Dry the solution obtained in step 4) at 110°C in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0282] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0283] 7) The filter cake obtained in step 6) was dried in a 110℃ forced-air drying oven for 8 hours, and finally ground into powder. The powder was heated from room temperature to 750℃ at 5℃ / min in a tube furnace under N2 atmosphere and held for 3 hours. After natural cooling to room temperature, the resulting catalyst was calculated as Pd1-Zr5 / CN5-750.

[0284] 2. Application of Catalyst 19 in the selective catalytic hydrogenation and sulfur removal of p-methylstyrene:

[0285] 0.08 mol of p-methylstyrene and Pd1-Zr5 / CN5-750 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 80 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 6.

[0286] Comparative Example 12

[0287] 1. A method for preparing a catalyst:

[0288] 1) Dissolve 8.33 g of palladium chloride powder in 20 mL of concentrated hydrochloric acid, then dilute the solution to 100 mL with deionized water to obtain a concentration of 0.05 g / mL. -1 The Pd precursor solution was left to stand until it was ready for use.

[0289] 2) Take 0.21g of urea and 1.9g of activated carbon (Fujian Xinsen Carbon Industry Co., Ltd., SAC-02B) and disperse them in 60mL of deionized water, and sonicate for 2h to make them evenly dispersed;

[0290] 3) After the mixture in step 2) is evenly mixed, filter, wash and dry in a vacuum drying oven at 110℃ for 6 hours to obtain CN carrier;

[0291] 4) Place 1.47 g of CN carrier from step 3) into a beaker, add 50 mL of anhydrous ethanol, and after stirring to form a slurry, slowly add 2.08 mL of 70 wt% zirconium propoxide solution to the slurry, then sonicate for 30 min and stir at 60 °C for 12 h.

[0292] 5) Dry the solution obtained in step 4) at 110°C in a forced-air drying oven, then add 60 mL of deionized water to form a slurry. Introduce 2 mL of the Pd precursor solution prepared in step 1) into the slurry, then sonicate for 30 min and stir at 60°C for 12 h.

[0293] 6) After soaking for 12 hours as in step 5), adjust the pH to 10 with 1 mol / L NaOH solution, then age for 2 hours, and finally reduce it with 20 times the molar amount of Pd NaBH4. The reduction is carried out under water bath heating at 60°C and 400 r·min. -1 Stir for 2 hours, then filter and wash with deionized water to neutralize.

[0294] 7) The filter cake obtained in step 6) was dried in a 110℃ forced-air drying oven for 8 hours, and finally ground into powder. The powder was heated from room temperature to 900℃ at 5℃ / min in a tube furnace under N2 atmosphere and held for 3 hours. After natural cooling to room temperature, the resulting catalyst was calculated as Pd1-Zr5 / CN5-900.

[0295] 2. Application of Catalyst 20 in the selective catalytic hydrogenation and desulfurization of p-methylstyrene:

[0296] 0.08 mol of p-methylstyrene and Pd1-Zr5 / CN5-900 catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 6.

[0297] Table 6. Effect of different calcination temperatures on reaction performance

[0298]

[0299] Different calcination temperatures result in different crystal forms of ZrO2 on the catalyst support. The XRD in the attached figure of the specification shows that monoclinic ZrO2 begins to appear from 450℃. As the calcination temperature increases, tetragonal ZrO2 also begins to appear. Based on the experimental phenomena, we can conclude that amorphous ZrO2 has the best catalytic performance.

[0300] Comparative Example 13

[0301] 0.08 mol of p-methylstyrene and 5 wt% Pd-Zr / CN catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 0.5 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 7.

[0302] Comparative Example 14

[0303] 0.08 mol of p-methylstyrene and 5 wt% Pd-Zr / CN catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2, and the airtightness of the reactor was checked. The reaction was carried out at 80 °C, with the mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 2 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 7.

[0304] Table 7. Effect of different reaction pressures on reaction performance

[0305]

[0306] Comparative Example 15

[0307] 0.08 mol of p-methylstyrene and 5 wt% Pd-Zr / CN catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 50 °C with a mechanical stirring rate controlled at 1000 r·min. -1 The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 8.

[0308] Comparative Example 16

[0309] 0.08 mol of p-methylstyrene and 5 wt% Pd-Zr / CN catalyst were placed in a 250 mL reactor, mixed with 80 mL of toluene, and then 2500 ppm of n-dodecyl mercaptan was added to the reactor. Subsequently, the air inside the reactor was repeatedly replaced with N2 to check the airtightness of the reactor. The reaction was carried out at 60 °C with a mechanical stirring rate controlled at 1000 r·min. -1The H2 pressure was controlled at 1 MPa. The hydrogenation products were quantitatively analyzed by an Anglient 7890B gas chromatograph, and the results are shown in Table 8.

[0310] Table 8. Effect of different temperatures on reaction performance

[0311]

[0312] Comparative Example 17

[0313] The reaction conditions and feed ratio were kept consistent with those in Example 1. The reacted catalyst 9-20 was placed in a 250 mL reactor. When the conversion rate of p-methylstyrene reached 20%, the catalytic reaction time was recorded, and the reaction was repeated five times. The hydrogenation products were quantitatively analyzed using an Anglient 7890B gas chromatograph. The results are shown in Table 9.

[0314] Table 9. Stability evaluation of catalysts.

[0315]

Claims

1. A method for preparing a bimetallic Pd-Zr / CN catalyst, characterized in that: The preparation method consists of the following steps: 1) Prepare aqueous solutions of Pd precursor and Zr precursor solutions respectively; 2) Activated carbon and the N precursor are dispersed in deionized water, ultrasonically treated for 1-2 h, filtered, washed, and dried to obtain the CN support. The activated carbon and the N precursor are added according to a ratio to achieve a theoretical N content of 2-5 wt% in the CN support. The theoretical N content = m N / (m N +m 活性炭 ) × 100%, where m N Represents the mass of N contained in the N precursor; 3) Mix CN carrier and ethanol, stir to form a slurry, then slowly add Zr precursor solution, sonicate for 0-60 min, stir at 40-70 ℃ for 12-24 h, centrifuge and dry to obtain Zr / CN; 4) Add the Zr / CN obtained in step 3) to deionized water and stir until homogeneous to form a slurry. Introduce the Pd precursor solution prepared in step 1) into the slurry, sonicate for 0-60 min, stir at 40-70 ℃ for 12-24 h, adjust the pH to 8-10 with alkaline solution, then precipitate and age for 2-3 h, add reducing agent for reduction, filter after reduction, wash thoroughly with deionized water, and finally dry to directly obtain the bimetallic Pd-Zr / CN catalyst. The CN support, Zr precursor, and Pd precursor are fed in such a manner that the theoretical Zr content in the bimetallic Pd-Zr / CN catalyst is 10-30 wt% and the theoretical Pd content is 4-5 wt%, respectively. The theoretical Zr content = m Zr / (m CN载体 +m Pd +m ZrO2 The theoretical content of Pd is calculated as m × 100%. Pd / (m CN载体 +m Pd +m ZrO2 )×100%, where m Pd m represents the mass of Pd contained in the Pd precursor. ZrO2 This represents the mass of ZrO2 calculated based on the mass of Zr contained in the Zr precursor.

2. The preparation method according to claim 1, characterized in that: The precursor of Pd is palladium chloride, palladium acetate, or palladium nitrate; the precursor of N is at least one of urea, melamine, and dicyandiamide; and the precursor of Zr is at least one of zirconium propoxide, zirconium oxychloride, zirconium nitrate pentahydrate, and zirconium chloride.

3. The preparation method according to claim 1, characterized in that: In step 2), the theoretical N content in the CN carrier is 5 wt%.

4. The preparation method according to claim 1, characterized in that: In steps 3) and 4), the ultrasound time is 30 min.

5. The preparation method according to claim 1, characterized in that: In step 4), the reducing agent is hydrazine hydrate, formaldehyde, hydrogen peroxide, or sodium borohydride. The molar amount of the reducing agent is 10-20 times the molar amount of Pd. The reduction conditions are: 50-80 ℃ water bath heating at 400-500 r·min. -1 Stir for 1-3 hours.

6. A bimetallic Pd-Zr / CN catalyst prepared by the method according to any one of claims 1-5.

7. The application of the bimetallic Pd-Zr / CN catalyst as described in claim 6 in the hydrogenation and antisulfurization system of unsaturated alkenes or aromatic nitro compounds.

8. The application as described in claim 7, characterized in that: The application specifically includes the following steps: Unsaturated alkene compounds or aromatic nitro compounds, bimetallic Pd-Zr / CN catalyst powder, and solvent are added to a reactor, and a continuous hydrogenation reaction is carried out under a hydrogen atmosphere to generate hydrogenation products; the unsaturated alkene compounds or aromatic nitro compounds contain sulfur-containing impurities.

9. The application as described in claim 8, characterized in that: The unsaturated olefin compound is styrene, p-methylstyrene, norbornene, or 2-[b-(2-thienyl)vinyl]benzoic acid; the aromatic nitro compound is 4-nitroanisole or 2-nitrodiphenyl sulfide; the sulfur-containing impurity is an organic sulfide; and the solvent is at least one of methanol, ethanol, toluene, dioxane, and N,N-dimethylformamide.

10. The application as described in claim 9, characterized in that: The hydrogenation reaction temperature is 70-150 ℃, and the hydrogenation reaction pressure is 0.8-3 MPa.

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