A sulfur-promoter-modified titanium-silicon molecular sieve immobilized gold catalyst and its preparation method and application

Abstract

The present invention provides a method for preparing a sulfur-modified titanium silicon molecular sieve solid-supported gold catalyst, comprising the following steps: (1) mixing a gold precursor solution, an alkaline solution, a titanium silicon molecular sieve and a sulfur promoter, and then drying to obtain a catalyst precursor; (2) subjecting the obtained catalyst precursor to an activation treatment to obtain a sulfur-modified titanium silicon molecular sieve solid-supported gold catalyst. The addition of a sulfur promoter can improve the dispersibility of gold particles in the catalyst, and the obtained gold catalyst has a smaller particle size of nano-gold particles. The sulfur-modified titanium silicon molecular sieve solid-supported gold catalyst prepared by the present invention is applied to the reaction of hydrogenation of propylene to produce PO and the reaction of hydrogenation of propane to produce acetone, and exhibits higher catalytic activity.

Description

Technical Field

[0001] The invention belongs to the technical field of catalysts, and specifically relates to a sulfur-assisted modified titanium silicon molecular sieve solid-supported gold catalyst and a preparation method and application thereof. Background Art

[0002] Propylene oxide (PO) is the second largest propylene derivative after polypropylene, and is mainly used to produce chemical products such as polyether polyols, propylene glycol, and propylene carbonate. Among the production processes of propylene oxide, the direct epoxidation of propylene with H2 and O2 to synthesize PO, namely the HOPO process, has long been regarded as an ideal process for PO production due to its advantages such as cheap and readily available raw materials and green and environmentally friendly processes.

[0003] Acetone is one of the important chemical raw materials. It is mainly used as a solvent and for the production of various chemical products such as methyl methacrylate (MMA), isopropanol, and polycarbonate intermediate bisphenol A. In recent years, with the rapid development of the polycarbonate industry and the epoxy resin industry, the consumption of products such as bisphenol A and MMA has increased significantly, driving the continuous growth of the domestic acetone market demand. Compared with the current mainstream isopropylbenzene method, the new process of direct oxidation of propane to acetone in a hydrogen / oxygen atmosphere shows unique advantages: the production raw materials are propane, hydrogen and oxygen, which are cheap and easy to obtain; the acetone selectivity is high and the atom economy is good; the process is simple, the reaction is carried out in the gas phase, and no organic solvent is required. In the current dual-carbon background, this method has received widespread attention at home and abroad.

[0004] At present, the catalyst used for the catalytic oxidation of propylene to produce PO and the catalytic oxidation of propane to produce acetone is a nano-gold catalyst immobilized on a titanium silicalite molecular sieve. Studies have found that this gold catalyst supported on a titanium silicalite molecular sieve is an Au-Ti bifunctional catalyst: the Au site catalyzes H2 and O2 to produce hydroperoxide species, which then diffuses to the Ti site to produce a Ti-OOH active intermediate, which catalyzes the oxidation of propylene or propane to produce PO and acetone, respectively.

[0005] A large number of studies have found that adding additives is an effective strategy to improve the catalytic performance of Au-Ti bifunctional catalysts. Among them, adding metal additives (such as Pt, Pd, etc.) to Au-Ti bifunctional catalysts will affect the particle size distribution and electronic structure of nano-gold, and the addition of metal additives may also form a bimetallic catalyst with gold, thereby playing a synergistic catalytic role. In addition, adding alkaline earth metal additives Mg and Ca and alkali metal additives Li, K, Cs, Ru to Au-Ti bifunctional catalysts will also affect the electronic structure and particle size distribution of gold. However, there are no reports on the effect of S additives on the performance of Au-Ti bifunctional catalysts.

[0006] At present, whether in the field of propylene hydrogenation to produce PO or propane hydrogenation to produce acetone, the overall performance of the prepared Au-Ti bifunctional catalyst still cannot meet the requirements of industrial production and application, and further development and research are needed. Summary of the invention

[0007] Aiming at the shortcomings of the existing catalyst preparation method and performance in the reaction of propylene hydrogenation to produce PO and the reaction of propane hydrogenation to produce acetone, the present invention provides a sulfur-assisted titanium silicon molecular sieve immobilized gold catalyst for the reaction of propylene hydrogenation to produce PO and the reaction of propane hydrogenation to produce acetone and a preparation method thereof.

[0008] The technical solution of the present invention is as follows: In the first aspect, a method for preparing a titanium silicon molecular sieve immobilized gold catalyst modified by a sulfur promoter is provided, comprising the following steps:

[0009] (1) mixing a gold precursor solution, an alkaline solution, a titanium silicon molecular sieve and a sulfur additive and drying the mixture to obtain a catalyst precursor;

[0010] (2) Activating the catalyst precursor to obtain a sulfur-modified titanium silicalite immobilized gold catalyst.

[0011] The present invention is further configured such that in step (1), the sulfur auxiliary agent is pre-mixed with a gold precursor solution and an alkaline solution and then mixed with the titanium silicon molecular sieve, and then dried to obtain a catalyst precursor.

[0012] Specifically, water and the gold precursor solution, alkaline solution and sulfur additive are mixed evenly, and then mixed with titanium silicon molecular sieve, and stirred evenly to obtain mixture I; mixture I is allowed to stand, washed and dried to obtain a catalyst precursor.

[0013] The present invention is further configured such that in step (1), the gold precursor solution, the alkaline solution and the titanium silicon molecular sieve are pre-mixed, dried and then mixed with the sulfur additive to obtain a catalyst precursor.

[0014] Specifically, water and the gold precursor solution, alkaline solution and titanium silicon molecular sieve are first mixed and stirred to obtain mixture I; mixture 1 is allowed to stand, washed and dried, and then mixed with a sulfur additive to obtain mixture II; mixture II is allowed to stand and dried to obtain a catalyst precursor.

[0015] The present invention is further configured that, before drying, the mixture obtained by mixing the gold precursor solution, the alkaline solution, the titanium silicon molecular sieve and the sulfur additive is first allowed to stand for 1-12 hours, preferably 6-12 hours.

[0016] It should be noted that the drying method in step (1) is a drying method conventionally used in the field of catalyst preparation, preferably vacuum drying.

[0017] The present invention is further configured such that the gold precursor in the gold precursor solution is selected from one or more of chloroauric acid, sodium chloroaurate, potassium chloroaurate, cesium chloroaurate, lithium chloroaurate or ammonium chloroaurate.

[0018] The present invention is further configured such that the alkali in the alkaline solution is selected from one or more of MOH, M2CO3, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide or tetrabutylammonium hydroxide, wherein M is Li, Na, K, Rb or Cs.

[0019] The present invention is further configured that the titanium silicon molecular sieve includes one or more of Ti-SBA-15, Ti-MCM-41, Ti-MCM-48, Ti-MCM-36, Ti-MWW, Ti-MOR, Ti-Beta, Ti-TUD-1, TS-1, multi-level pore TS-1, TS-2 and multi-level pore TS-2. The titanium silicon molecular sieve is a titanium silicon molecular sieve conventionally used in the field of propylene hydroxide epoxidation to produce propylene oxide or propane hydroxide to produce acetone, and can be a titanium silicon molecular sieve that has been calcined or a titanium silicon molecular sieve that has not been calcined and whose pores are blocked by a template agent.

[0020] The present invention is further configured such that the sulfur auxiliary agent includes one or more of dithionite, thiosulfate, sulfite, sulfate, pyrosulfate, persulfate, sulfurous acid, sulfuric acid, thiophene and its derivatives, organic sulfonic acid, thiol, thiophenol, sulfur-containing silane or thioether.

[0021] The present invention is further configured such that, in step (2), the activation treatment is carried out in the presence of an activation atmosphere, which is air, a reducing atmosphere or an inert atmosphere; and the activation temperature is 150 to 400°C, preferably 200-350°C, and more preferably 300-325°C.

[0022] The present invention is further configured such that the particle size of the nano-gold particles on the sulfur-adjuvant-modified titanium silicon molecular sieve solid-supported gold catalyst is less than 10 nm, preferably less than 5 nm, and more preferably less than 3.5 nm.

[0023] The second aspect of the present invention provides a sulfur-promoter-modified titanium silicalite immobilized gold catalyst prepared according to the above preparation method.

[0024] The third aspect of the present invention provides an application of the above-mentioned sulfur promoter-modified titanium silicalite immobilized gold catalyst for the propylene hydroxoepoxidation reaction to produce PO and the propane hydroxoepoxidation reaction to produce acetone.

[0025] The present invention has the following beneficial effects: the prepared sulfur-adjuvant-modified titanium-silicon molecular sieve solid-supported gold catalyst can improve the dispersibility of gold particles on the supported Au-Ti bifunctional catalyst and reduce the particle size of nano-gold particles compared to the Au-Ti bifunctional catalyst without sulfur-adjuvant, thereby greatly improving the activity of the catalyst, and has a more excellent catalytic effect on the reaction of propylene hydroxyl epoxidation to PO and the reaction of propane hydrogenation to acetone. The present invention not only adopts a new preparation method of an efficient Au-Ti bifunctional catalyst for propylene / propane hydrogenation reaction, but also provides an effective solution for improving the catalytic activity of zeolite-supported gold nanocatalysts for other reactions. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 HAADF-STEM image and particle size distribution diagram of the catalyst prepared in Example 1.

[0027] Figure 2 HAADF-STEM image and particle size distribution diagram of the catalyst prepared in Comparative Example 1.

[0028] Figure 3 The catalytic activity results of the catalysts prepared in Example 1 and Comparative Example 1 in propylene hydrooxyepoxidation reaction are compared.

[0029] Figure 4 The catalytic activity results of the catalysts prepared in Example 3 and Comparative Example 3 in propane hydrogenation reaction are compared. DETAILED DESCRIPTION

[0030] The technical scheme of the present invention is described clearly and completely below in conjunction with specific embodiments. It should be understood that the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of the present invention. The experimental methods in the following embodiments that do not specify specific conditions are usually carried out under conventional conditions or according to the conditions recommended by the manufacturer. Unless otherwise stated, all percentages, ratios, proportions, or parts are by weight, and room temperature refers to a temperature of 20-30°C.

[0031] Example 1

[0032] The Au-Ti bifunctional catalyst was prepared by using potassium carbonate aqueous solution as alkaline solution, chloroauric acid as precursor, uncalcined TS-1 (i.e., TS-1-B) as carrier, and ammonium sulfate aqueous solution as sulfur promoter, and the steps are as follows:

[0033] (1) Use a pipette to weigh 2 mL of chloroauric acid aqueous solution (0.01 g Au / mL), placed in a 10mL glass beaker, added with 6.5mL of water, then added dropwise with 0.5mL of potassium carbonate aqueous solution (0.6M), then added with 1.0mL of ammonium sulfate aqueous solution (0.25M), mixed and stirred at room temperature for 4h to obtain a mixed solution 1; then 0.5mL of the mixed solution 1 was added dropwise with 1.0g of TS-1-B, then stirred evenly with a glass rod, allowed to stand at room temperature for 12h, and then vacuum dried at room temperature overnight.

[0034] (2) The catalyst precursor obtained after drying was placed in a fixed bed reactor, and the temperature was raised from room temperature to 320° C. at a rate of 1° C. / min and maintained for 2 h under the conditions of hydrogen / nitrogen = 2:3 (volume ratio) and a gas flow rate of 50 mL / min to obtain a sulfur-modified supported Au-Ti bifunctional catalyst with a gold loading of 0.09 wt%.

[0035] Comparative Example 1

[0036] The Au-Ti bifunctional catalyst was prepared using potassium carbonate aqueous solution as the alkaline solution, chloroauric acid as the precursor, and uncalcined TS-1 (i.e., TS-1-B) as the carrier, and the steps are as follows:

[0037] (1) Use a pipette to weigh 2 mL of chloroauric acid aqueous solution (0.01 g Au / mL), placed in a 10mL glass beaker, added with 6.5mL of water, and then added dropwise with 0.5mL of potassium carbonate aqueous solution (0.6M), mixed and stirred at room temperature for 4h to obtain a mixed solution 1; then 0.5mL of the mixed solution 1 was added dropwise with 1.0g of TS-1-B, and then stirred evenly with a glass rod, allowed to stand at room temperature for 12h, and then vacuum dried at room temperature overnight.

[0038] (2) The catalyst precursor obtained after drying was placed in a fixed bed reactor, and the temperature was raised from room temperature to 320° C. at a rate of 1° C. / min and maintained for 2 h under the conditions of hydrogen / nitrogen = 2:3 (volume ratio) and a gas flow rate of 50 mL / min to obtain a supported Au-Ti bifunctional catalyst with a gold loading of 0.10 wt%.

[0039] The gold catalysts prepared in Example 1 and Comparative Example 1 were characterized by HAADF-STEM, and the corresponding characterization results were as follows: Figure 1 and Figure 2 As shown, compared with Comparative Example 1, the sulfur-adjuvant-modified titanium silicon molecular sieve supported gold catalyst prepared in Example 1 has a smaller nano-gold particle size.

[0040] Example 2

[0041] The Au-Ti bifunctional catalyst is prepared using sodium hydroxide aqueous solution as the alkaline solution, chloroauric acid as the precursor, Ti-SBA-15 as the carrier, and sodium sulfate aqueous solution as the sulfur promoter. The steps are as follows:

[0042] (1) Use a pipette to weigh 15 mL of chloroauric acid aqueous solution (0.01 g Au / mL), placed in a 50mL glass beaker, added with 2.5mL water and 7.5mL sodium sulfate aqueous solution (0.5M), then added with 1.0g Ti-SBA-15, and then added with sodium hydroxide aqueous solution (0.5M) dropwise, mixed and stirred at room temperature for 9h, then centrifuged, washed (50mL water) and vacuum dried at room temperature overnight.

[0043] (2) The catalyst precursor obtained after drying was placed in a fixed bed reactor, and the temperature was increased from room temperature to 300° C. at a rate of 1° C. / min in an air atmosphere at a gas flow rate of 50 mL / min and maintained for 2 h to obtain a sulfur-modified supported Au-Ti bifunctional catalyst with a gold loading of 0.29 wt%.

[0044] Comparative Example 2

[0045] The Au-Ti bifunctional catalyst was prepared using sodium hydroxide aqueous solution as the alkaline solution, chloroauric acid as the precursor, and Ti-SBA-15 as the carrier. The steps are as follows:

[0046] (1) Use a pipette to weigh 15 mL of chloroauric acid aqueous solution (0.01 g Au / mL), placed in a 50mL glass beaker, added with 10mL water, then added with 1.0g Ti-SBA-15, and then added dropwise with sodium hydroxide aqueous solution (0.5M), mixed and stirred at room temperature for 9h, and then centrifuged, washed (50mL water) and vacuum dried at room temperature overnight.

[0047] (2) The catalyst precursor obtained after drying was placed in a fixed bed reactor, and the temperature was increased from room temperature to 300° C. at a rate of 1° C. / min in an air atmosphere at a gas flow rate of 50 mL / min and maintained for 2 h to obtain a sulfur-modified supported Au-Ti bifunctional catalyst with a gold loading of 0.30 wt%.

[0048] Example 3

[0049] The Au-Ti bifunctional catalyst was prepared using tetraethylammonium hydroxide aqueous solution as the alkaline solution, potassium chloroaurate as the precursor, TS-1-B as the carrier, and mercaptopropyltrimethoxysilane as the sulfur promoter. The steps are as follows:

[0050] (1) Use a pipette to weigh 2 mL of potassium chloroaurate aqueous solution (0.01 g Au / mL), placed in a 10mL glass beaker, added with 2mL of water, 6mL of tetraethylammonium hydroxide aqueous solution (25wt%) and 0.12g of mercaptopropyltrimethoxysilane, mixed and stirred at room temperature for 8h to obtain a mixed solution 1; 0.4mL of the mixed solution 1 was dripped dropwise into 1.0g of TS-1-B, while stirring, and after stirring evenly, allowed to stand at room temperature for 12h, and then vacuum dried at room temperature overnight.

[0051] (2) The catalyst precursor obtained after drying was placed in a fixed bed reactor, and the temperature was raised from room temperature to 300° C. at a rate of 1° C. / min and maintained for 2 h under the conditions of hydrogen / nitrogen = 2:3 (volume ratio) and a gas flow rate of 50 mL / min to obtain a sulfur-modified supported Au-Ti bifunctional catalyst with a gold loading of 0.08 wt%.

[0052] Comparative Example 3

[0053] The Au-Ti bifunctional catalyst was prepared using tetraethylammonium hydroxide aqueous solution as the alkaline solution, potassium chloroaurate as the precursor, and TS-1-B as the carrier. The steps are as follows:

[0054] (1) Use a pipette to weigh 2 mL of potassium chloroaurate aqueous solution (0.01 g Au / mL), placed in a 10mL glass beaker, added with 2mL of water and 6mL of tetraethylammonium hydroxide aqueous solution (25wt%), mixed and stirred at room temperature for 8h to obtain a mixed solution 1; 0.40mL of the mixed solution 1 was dripped dropwise into 1.0g of TS-1-B, stirred while adding dropwise, and allowed to stand at room temperature for 12h after stirring evenly, and then vacuum dried at room temperature overnight.

[0055] (2) The catalyst precursor obtained after drying was placed in a fixed bed reactor, and the temperature was raised from room temperature to 300° C. at a rate of 1° C. / min and maintained for 2 h under the conditions of hydrogen / nitrogen = 2:3 (volume ratio) and a gas flow rate of 50 mL / min to obtain a sulfur-modified supported Au-Ti bifunctional catalyst with a gold loading of 0.08 wt%.

[0056] Example 4

[0057] The Au-Ti bifunctional catalyst was prepared using potassium hydroxide aqueous solution as the alkaline solution, chloroauric acid as the precursor, uncalcined TS-1 (i.e., TS-1-B) as the carrier, and ethyl mercaptan solution dissolved in ethanol as the sulfur promoter. The steps are as follows:

[0058] (1) Use a pipette to weigh 2 mL of chloroauric acid aqueous solution (0.01 g Au / mL), placed in a 10mL glass beaker, added 7.5mL water, then added 0.5mL potassium hydroxide aqueous solution (0.5M) dropwise, mixed and stirred at room temperature for 4h to obtain a mixed solution 1; then 0.5mL of the mixed solution 1 was added dropwise to 1.0g TS-1 whose micropores were blocked by the template agent, then stirred evenly with a glass rod, left standing at room temperature for 12h, and then vacuum dried overnight at room temperature. 0.5mL of ethanethiol solution (0.50M) dissolved in ethanol was dripped into the above-mentioned dried solid dropwise, stirred while dropping, left standing at room temperature for 12h after stirring evenly, and then vacuum dried overnight at room temperature.

[0059] (2) The catalyst precursor obtained after drying was placed in a fixed bed reactor, and the temperature was raised from room temperature to 325° C. at a rate of 1° C. / min and maintained for 2 h under the conditions of hydrogen / nitrogen = 2:3 (volume ratio) and a gas flow rate of 50 mL / min to obtain a sulfur-modified supported Au-Ti bifunctional catalyst with a gold loading of 0.09 wt%.

[0060] Comparative Example 4

[0061] The Au-Ti bifunctional catalyst was prepared using potassium hydroxide aqueous solution as the alkaline solution, chloroauric acid as the precursor, and uncalcined TS-1 (i.e., TS-1-B) as the carrier, and the steps are as follows:

[0062] (1) Use a pipette to weigh 2 mL of chloroauric acid aqueous solution (0.01 g Au / mL), placed in a 10mL glass beaker, added with 7.5mL water, then added dropwise with 0.5mL potassium hydroxide aqueous solution (0.5M), mixed and stirred at room temperature for 4h to obtain a mixed solution 1; then 0.5mL of the mixed solution 1 was added dropwise with 1.0g TS-1 whose micropores were blocked by the template agent, and then stirred evenly with a glass rod, allowed to stand at room temperature for 12h, and then vacuum dried at room temperature overnight.

[0063] (2) The catalyst precursor obtained after drying was placed in a fixed bed reactor, and the temperature was raised from room temperature to 325° C. at a rate of 1° C. / min and maintained for 2 h under the conditions of hydrogen / nitrogen = 2:3 (volume ratio) and a gas flow rate of 50 mL / min to obtain a supported Au-Ti bifunctional catalyst with a gold loading of 0.10 wt%.

[0064] Example 5

[0065] The catalytic performance of the gold catalysts prepared in Examples 1-4 and Comparative Examples 1-4 was evaluated in the reaction of preparing propylene oxide by hydro-epoxidation of propylene. The propylene gas phase epoxidation reaction was carried out in a fixed bed reactor at atmospheric pressure. The reaction atmosphere was composed of propylene: hydrogen: oxygen: nitrogen = 1:1:1:7 (volume ratio), and the space velocity was 14000 mL·h-1 ·g cat -1 The outlet product was analyzed by gas chromatography. The catalytic results are shown in Table 1. Figure 3 The results show the comparison of the catalytic activity of the catalysts prepared in Example 1 and Comparative Example 1 in the propylene hydrooxyepoxidation reaction.

[0066] Table 1 Catalytic performance of catalysts in the epoxidation of propylene to produce propylene oxide

[0067]

[0068] Combining Table 1 and Figure 3 It can be seen from the results that the catalyst modified with the sulfur promoter prepared in the example has a higher hydrogen utilization rate and a higher PO generation rate for the reaction of propylene hydrooxidation to prepare propylene oxide, that is, it has a higher catalytic activity, compared with the catalyst not modified with the sulfur promoter.

[0069] Example 6

[0070] The catalytic performance of the catalysts prepared in Examples 1 and 3 and Comparative Examples 1 and 3 was evaluated in the reaction of producing acetone by hydrogenation of propane. The reaction of producing acetone by hydrogenation of propane was carried out in a fixed bed reactor at atmospheric pressure. The reaction atmosphere was composed of propane: hydrogen: oxygen: nitrogen = 1:1:1:7 (volume ratio), and the space velocity was 14000 mL·h -1 ·g cat -1 The outlet product was analyzed by gas chromatography. The catalytic results are shown in Table 2. Figure 4 The results show the comparison of the catalytic activity of the catalysts prepared in Example 3 and Comparative Example 3 in the reaction of hydrogenating propane to produce acetone.

[0071] Table 2 Catalytic performance of catalysts in the reaction of propane hydrogenation to produce acetone

[0072]

[0073] Combining Table 2 and Figure 4 It can be seen from the results that the catalyst modified with the sulfur promoter prepared in the example has a higher hydrogen utilization rate and a higher acetone generation rate for the reaction of hydrogenating propane to prepare acetone than the catalyst not modified with the sulfur promoter. That is, the titanium silicalite molecular sieve supported gold catalyst modified with the sulfur promoter prepared in the present invention has a higher catalytic activity for catalyzing the reaction of hydrogenating propane to prepare acetone.

Claims

1. A method for preparing a sulfur-promoter-modified titanium silicon molecular sieve immobilized gold catalyst, characterized in that: The steps include: (1) firstly mixing a gold precursor solution, an alkaline solution, a titanium silicon molecular sieve and a sulfur additive and then drying them to obtain a catalyst precursor; (2) Activating the obtained catalyst precursor to obtain a sulfur-modified titanium silicon molecular sieve supported gold catalyst; wherein the gold precursor in the gold precursor solution is selected from one or more of chloroauric acid, sodium chloroaurate, potassium chloroaurate, cesium chloroaurate, lithium chloroaurate or ammonium chloroaurate; and the sulfur-modified agent is selected from one or more of sulfate, sulfuric acid, thiol and sulfur-containing silane.

2. The preparation method according to claim 1, characterized in that: In step (1), the sulfur promoter is pre-mixed with a gold precursor solution and an alkaline solution and then mixed with a titanium silicon molecular sieve, and dried to obtain a catalyst precursor; or, The gold precursor solution, the alkaline solution and the titanium silicon molecular sieve are pre-mixed, dried and then mixed with the sulfur auxiliary agent, and dried to obtain a catalyst precursor.

3. The preparation method according to claim 1, characterized in that: The alkali in the alkaline solution is selected from one or more of MOH, M2CO3, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide or tetrabutylammonium hydroxide, wherein M is Li, Na, K, Rb or Cs.

4. The preparation method according to claim 1, characterized in that: The titanium silicon molecular sieve includes one or more of Ti-SBA-15, Ti-MCM-41, Ti-MCM-48, Ti-MCM-36, Ti-MWW, Ti-MOR, Ti-Beta, Ti-TUD-1, TS-1, multi-level pore TS-1, TS-2 and multi-level pore TS-2.

5. The preparation method according to claim 1, characterized in that: In step (2), the activation treatment is carried out in the presence of an activation atmosphere, which is air, a reducing atmosphere or an inert atmosphere; the activation temperature is 150-400 o C.

6. The preparation method according to claim 5, characterized in that: In step (2), the activation temperature is 200-350 o C.

7. The preparation method according to claim 6, characterized in that: In step (2), the activation temperature is 300-325 o C.

8. The preparation method according to claim 1, characterized in that: The particle size of the nano-gold particles on the titanium silicon molecular sieve solid-supported gold catalyst modified by the sulfur promoter is less than 5 nm.

9. The preparation method according to claim 8, characterized in that: The particle size of the nano-gold particles on the sulfur-promoter-modified titanium-silicon molecular sieve solid-supported gold catalyst is less than 3.5 nm.

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