Platinum-containing catalyst as well as preparation method and application thereof

Abstract

The invention discloses a platinum-containing catalyst as well as a preparation method and application thereof, and belongs to the technical field of catalysts. The preparation method of the platinum-containing catalyst comprises the following steps: S1, preparing a carrier: mixing a zirconium-containing compound and (NH4) 2SO4, grinding, and calcining for the first time to obtain a sulfur modified carrier; and S2, loading platinum: uniformly mixing a platinum-containing solution with the sulfur modified carrier, heating to completely evaporate the solvent, drying, and calcining for the second time to obtain the platinum-containing catalyst. The invention discloses a preparation method of a platinum-containing catalyst, which comprises the following steps: grinding and mixing a zirconium-containing compound and ammonium sulfate, calcining for the first time to obtain a sulfur modified carrier, loading platinum, and calcining for the second time to obtain the platinum-containing catalyst. The operation of the sulfate modified carrier is mild, and the obtained platinum-containing catalyst has high catalytic activity and stability under the condition of low Pt loading capacity.

Description

Technical Field

[0001] The present invention relates to catalyst technology, and in particular to a platinum-containing catalyst, a preparation method thereof, and an application thereof. Background Art

[0002] Volatile organic compounds (VOCs) refer to organic compounds that have a relatively high saturated vapor pressure, a low boiling point, a small molecular weight, and are easily volatile at normal temperature under standard conditions. Such substances are one of the main pollutants in the atmosphere. They participate in the formation of secondary pollutants such as fine particulate matter (PM2.5) and ozone (O 3 ), thereby triggering atmospheric environmental problems such as haze and photochemical smog, resulting in serious environmental pollution and endangering human health. Therefore, controlling the emission of VOCs is crucial. Among them, catalytic combustion of VOCs is one of the most effective and promising methods. In the catalytic combustion technology, the performance of the catalyst plays a key role in the efficiency of VOCs emission reduction. Noble metal (Pt, Pd, Ru) catalysts have attracted extensive attention in the field of VOCs catalytic oxidation due to their high activity and thermal stability.

[0003] There are many types of VOCs. The most concerned ones are straight-chain saturated light alkanes (C n H 2n+2 , n ≥ 2) represented by propane. Propane widely exists in the emission process in the petrochemical field. Due to its stable structure, it usually requires a highly active catalyst and a relatively high reaction temperature, and is a model reactant for difficult-to-treat VOCs. Pt-based catalysts are considered to be one of the catalysts with the highest activity for the complete oxidation reaction of propane. However, due to the scarcity of noble metals and the continuous increase in prices, it is urgent to improve the activity of Pt-based catalysts to achieve high catalytic activity, high stability, and reduction of noble metals under low-temperature conditions.

[0004] The catalytic performance of noble metals is affected by various factors. For example, the acid strength of the carrier can affect its catalytic activity by controlling the oxidation state of Pt. Han et al. acidified CeO 2 nanorods with molybdic acid, phosphoric acid, and sulfuric acid, and then loaded Pt onto the nanorods. Compared with the Pt / CeO 2 catalyst, the catalytic combustion performance of the Mo acid-modified Pt / CeO 2 catalyst for propane was significantly improved. The results show that on the 1% Pt / CeO 2 -18Mo catalyst, Pt 2+ and Pt 4+Coexistence, along with a relatively large number of acidic sites, redox sites, and adsorbed oxygen, is the reason for the improved catalytic performance of the catalyst. In addition, the structure of the support is also one of the factors affecting the catalytic performance of Pt-based catalysts. Liu et al. constructed two ordered mesoporous catalysts with different confinement structures, namely pore-confined catalyst (0.3%Pt / Ti 0.1 AlO y -VI) and framework-confined catalyst (0.3% / Pt / Ti 0.1 AlO y -EISA). Among them, the framework-confined catalyst (0.3%Pt / Ti 0.1 AlO y -EISA) exhibits better propane oxidation activity and thermal stability, while the pore-confined catalyst (0.3%Pt / Ti 0.1 AlO y -VI) has better water resistance and sulfur resistance because the pores protect the active sites from being covered by sulfates to a certain extent, and the sulfates increase the acidity of the catalyst, thereby improving the water resistance and sulfur resistance of the catalyst. Finally, the state of noble metal species can also affect the catalytic activity of noble metal catalysts. Ge et al. loaded Pt NPs of various sizes (1.3 - 7 nm) on nanocubic CeO with a clearly exposed plane (100) 2 , and systematically studied the effect of Pt size on the complete oxidation activity of propane. The results show that when the Pt NPs of the catalyst are less than 4 nm, the formation of positively charged Pt sites hinders the adsorption and activation of propane and reduces the propane oxidation activity. On the contrary, when the particle size exceeds 4 nm, metallic Pt particles dominate and the geometric structure also begins to affect the activity. The dual factors of electronics and geometry result in a volcano-shaped relationship between the reaction rate and the Pt particle size.

[0005] Li et al. prepared an H 2 SO 4 -modified ZrO 2 support by the impregnation method to obtain a 1 wt%Pt-xSO 4 2- / ZrO 2 catalyst (x represents the actual content of SO 4 2- in the catalyst). Compared with the Pt / ZrO 2 catalyst, the catalytic activity of propane is significantly improved. However, this method requires the use of sulfuric acid, which has higher requirements for equipment anti-corrosion and operation safety. Summary of the Invention

[0006] The object of the present invention is to provide a preparation method of a platinum-containing catalyst modified with sulfate without using sulfuric acid; another object of the present invention is to provide a platinum-containing catalyst with high catalytic activity, low Pt loading and high stability; the present invention also provides an application method of a platinum-containing catalyst with high catalytic activity, low Pt loading and high stability.

[0007] The present invention discloses a preparation method of a platinum-containing catalyst, comprising the following steps:

[0008] S1 Prepare a support: Mix a zirconium-containing compound and (NH 4 ) 2 SO 4 Mix, grind, and calcine for the first time to obtain a sulfur-modified support;

[0009] S2 Load platinum: Mix a platinum-containing solution with the sulfur-modified support evenly, heat to completely evaporate the solvent, dry, and calcine for the second time to obtain a platinum-containing catalyst.

[0010] The zirconium-containing compound includes ZrO 2 (zirconia), zirconium carbonate, ZrOCO 3 (basic zirconium carbonate).

[0011] The sulfur-modified support is a ZrO 2 support modified with sulfate.

[0012] Furthermore, in the step S1, the zirconium-containing compound includes ZrOCO 3 .

[0013] Furthermore, in the step S1, the mass ratio of (NH 4 ) 2 SO 4 to ZrOCO 3 is (0.025 - 0.2):1.

[0014] Preferably, the mass ratio of (NH 4 ) 2 SO 4 to ZrOCO 3 is (0.05 - 0.1):1.

[0015] Furthermore, in the step S1, the temperature control range of the first calcination is 500 - 600 °C, and the calcination time is 2 - 4 h.

[0016] Furthermore, in the step S2, the platinum-containing solution includes an aqueous solution of platinum nitrate.

[0017] Further, in the step S2, the mass ratio of the platinum-containing solute in the platinum-containing solution to the mass of the sulfur-modified carrier is (0.0005 - 0.02):1.

[0018] Preferably, the mass ratio of the platinum-containing solute in the platinum-containing solution to the mass of the sulfur-modified carrier is (0.005 - 0.01):1.

[0019] Further, in the step S1, the mass ratio of (NH 4 ) 2 SO 4 to ZrOCO 3 is 0.05:1; in the step S2, the mass ratio of the solute in the platinum-containing solution to the mass of the sulfur-modified carrier is 0.01:1.

[0020] Controlling the ratio within this range results in the highest catalytic activity of the obtained platinum-containing catalyst.

[0021] Further, in the step S2, the temperature control range for the second calcination is 450 - 550 °C, and the calcination time is 3 - 5 h.

[0022] The present invention also discloses a platinum-containing catalyst obtained by the preparation method described above.

[0023] The present invention also discloses an application of a platinum-containing catalyst, such as a platinum-containing catalyst as described above being applied to catalyze the combustion of volatile organic compounds.

[0024] In the preparation method of the platinum-containing catalyst disclosed by the present invention, after grinding and mixing a zirconium-containing compound and ammonium sulfate, a sulfur-modified carrier is obtained through the first calcination, then platinum is loaded, and a platinum-containing catalyst is obtained through the second calcination. The operation of modifying the carrier with sulfate adopted by the present invention is mild, and the obtained platinum-containing catalyst has high catalytic activity and stability under the condition of low Pt loading. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a graph showing the relationship between the temperature and conversion rate of propane catalyzed by the platinum-containing catalysts in Examples 1 - 4 of the present invention;

[0026] Figure 2 is a graph showing the relationship between the temperature and conversion rate of propane catalyzed by the platinum-containing catalysts in Examples 2, 5 - 8 of the present invention;

[0027] Figure 3 is a graph showing the relationship between the temperature and conversion rate of propane catalyzed by the catalysts in Examples 2, 9 and Comparative Examples 1 - 3 of the present invention;

[0028] Figure 4It is the Pt 4f XPS spectrum of the platinum-containing catalyst in Examples 1-3 of the present invention;

[0029] Figure 5 It is the relationship diagram between the reaction time and conversion rate of propane catalyzed by the platinum-containing catalyst in Example 2 of the present invention. Detailed implementation manners

[0030] To make the technical solutions of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and specific embodiments.

[0031] Example 1

[0032] Prepare a platinum-containing catalyst:

[0033] (1) Prepare the carrier

[0034] According to the mass ratio of (NH 4 ) 2 SO 4 to ZrOCO 3 being 0.025:1, weigh 4 g of ZrOCO 3 powder and 0.1 g of (NH 4 ) 2 SO 4 , mix and grind for about 45 minutes, and heat the mixture in a muffle furnace at a rate of 10 o °C / min to 550 o °C and calcine for 3 hours to obtain a sulfur-modified carrier.

[0035] (2) Load platinum

[0036] According to the mass ratio of the platinum-containing solute to the sulfur-modified carrier being 0.01:1, adopt the impregnation method, mix 1 g of the sulfur-modified carrier with 5 mL of Pt(NO 3 ) 2 aqueous solution (concentration 0.002 g / mL), stir, and let stand at room temperature for 3 hours. Stir the mixture at a water bath temperature of 90 °C, evaporate to dryness, and then dry the powdery solid in an oven at 100 o °C for 1 hour. Then heat it in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcine for 4 hours to obtain a platinum-containing catalyst.

[0037] Example 2

[0038] Prepare a platinum-containing catalyst:

[0039] (1) Prepare the carrier

[0040] According to (NH 4 ) 2 SO4 The mass ratio of [substance name] to ZrOCO 3 is 0.05:1. Weigh 4 g of ZrOCO 3 powder and 0.2 g of (NH 4 ) 2 SO 4 Mix and grind for about 45 minutes. Heat the mixture in a muffle furnace at a rate of 10 o °C / min to 550 o °C and calcine for 3 hours to obtain a sulfur-modified support.

[0041] (2) Loading platinum

[0042] According to the mass ratio of the platinum-containing solute to the sulfur-modified support being 0.01:1, using the impregnation method, mix 1 g of the sulfur-modified support with 5 mL of Pt(NO 3 ) 2 aqueous solution (concentration 0.002 g / mL) and stir. Let it stand at room temperature for 3 hours. Stir the mixture at a water bath temperature of 90°C, evaporate to dryness, and then dry the powdery solid in an oven at 100 o °C for 1 hour. Then heat in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcine for 4 hours to obtain a platinum-containing catalyst.

[0043] Example 3

[0044] Preparation of a platinum-containing catalyst:

[0045] (1) Preparation of the support

[0046] According to the mass ratio of (NH 4 ) 2 SO 4 to ZrOCO 3 being 0.07:1, weigh 4 g of ZrOCO 3 powder and 0.28 g of (NH 4 ) 2 SO 4 Mix and grind for about 45 minutes. Heat the mixture in a muffle furnace at a rate of 10 o °C / min to 550 o °C and calcine for 3 hours to obtain a sulfur-modified support.

[0047] (2) Loading platinum

[0048] According to the mass ratio of the platinum-containing solute to the sulfur-modified support being 0.01:1, using the impregnation method, mix 1 g of the sulfur-modified support with 5 mL of Pt(NO 3 ) 2The mixture was stirred in a water bath at 90°C and the powdered solid was evaporated to dryness and then heated at 100°C. o C oven for 1 hour. Then dry in a muffle furnace at 10 o C / min and the temperature was raised to 500 o C was calcined for 4 hours to obtain a platinum-containing catalyst.

[0049] Example 4

[0050] Preparation of platinum-containing catalyst:

[0051] (1) Preparation of carrier

[0052] According to (NH 4 ) 2 SO 4 The quality of ZrOCO 3 The mass ratio of ZrOCO is 0.2:1. Weigh 4g ZrOCO 3 powder and 0.8 g (NH 4 ) 2 SO 4 The mixture was mixed and ground for about 45 minutes and then placed in a muffle furnace at 10 o C / min to 550 o C was calcined for 3 hours to obtain a sulfur-modified support.

[0053] (2) Platinum loading

[0054] According to the mass ratio of the platinum-containing solute to the sulfur-modified support of 0.01:1, 1 g of the sulfur-modified support was impregnated with 5 mL of Pt(NO 3 ) 2 The mixture was stirred in a water bath at 90°C and the powdered solid was evaporated to dryness and then heated at 100°C. o C oven for 1 hour. Then dry in a muffle furnace at 10 o C / min and the temperature was raised to 500 o C was calcined for 4 hours to obtain a platinum-containing catalyst.

[0055] Example 5

[0056] Preparation of platinum-containing catalyst:

[0057] (1) Preparation of carrier

[0058] According to (NH 4 ) 2 SO 4 The quality of ZrOCO 3The mass ratio is 0.05:1. Weigh 4 g of ZrOCO 3 powder and 0.2 g of (NH 4 ) 2 SO 4 Mix and grind for about 45 minutes. Heat the mixture in a muffle furnace at a rate of 10 o °C / min to 550 o °C and calcine for 3 hours to obtain a sulfur-modified support.

[0059] (2) Loading platinum

[0060] According to the mass ratio of the platinum-containing solute to the sulfur-modified support being 0.02:1, using the impregnation method, mix 1 g of the sulfur-modified support with 10 mL of Pt(NO 3 ) 2 aqueous solution (concentration 0.002 g / mL) and stir. Let it stand at room temperature for 3 hours. Stir the mixture at a water bath temperature of 90°C, evaporate to dryness, and then dry the powdery solid in an oven at 100 o °C for 1 hour. Then heat in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcine for 4 hours to obtain a platinum-containing catalyst.

[0061] Example 6

[0062] Preparation of a platinum-containing catalyst:

[0063] (1) Preparation of the support

[0064] According to the mass ratio of (NH 4 ) 2 SO 4 to ZrOCO 3 being 0.05:1, weigh 4 g of ZrOCO 3 powder and 0.2 g of (NH 4 ) 2 SO 4 Mix and grind for about 45 minutes. Heat the mixture in a muffle furnace at a rate of 10 o °C / min to 550 o °C and calcine for 3 hours to obtain a sulfur-modified support.

[0065] (2) Loading platinum

[0066] According to the mass ratio of the platinum-containing solute to the sulfur-modified support being 0.005:1, using the impregnation method, mix 1 g of the sulfur-modified support with 2.5 mL of Pt(NO 3 ) 2Mix with an aqueous solution (concentration 0.002 g / mL), then add 2.5 mL of deionized water and stir. Let it stand at room temperature for 3 hours. Stir the mixture at a water bath temperature of 90 °C, and after evaporation to dryness, dry the powdery solid in an oven at 100 o C for 1 hour. Then heat it in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcine for 4 hours to obtain a platinum-containing catalyst.

[0067] Example 7

[0068] Prepare a platinum-containing catalyst:

[0069] (1) Prepare the support

[0070] According to the mass ratio of (NH 4 ) 2 SO 4 to ZrOCO 3 being 0.05:1, weigh 4 g of ZrOCO 3 powder and 0.2 g of (NH 4 ) 2 SO 4 and mix and grind for about 45 minutes. Heat the mixture in a muffle furnace at a rate of 10 o °C / min to 550 o °C and calcine for 3 hours to obtain a sulfur-modified support.

[0071] (2) Load platinum

[0072] According to the mass ratio of the platinum-containing solute to the sulfur-modified support being 0.001:1, use the impregnation method to mix 1 g of the sulfur-modified support with 0.5 mL of Pt(NO 3 ) 2 aqueous solution (concentration 0.002 g / mL), then add 4.5 mL of deionized water and stir. Let it stand at room temperature for 3 hours. Stir the mixture at a water bath temperature of 90 °C, and after evaporation to dryness, dry the powdery solid in an oven at 100 o °C for 1 hour. Then heat it in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcine for 4 hours to obtain a platinum-containing catalyst.

[0073] Example 8

[0074] Prepare a platinum-containing catalyst:

[0075] (1) Prepare the support

[0076] According to (NH 4 ) 2 SO 4The mass ratio of [substance] to ZrOCO is 0.05:1. Weigh 4 g of ZrOCO 3 powder and 0.2 g of (NH 3 ) 4 ) 2 SO 4 Mix and grind for about 45 minutes. Heat the mixture in a muffle furnace at a rate of 10 o °C / min to 550 o °C and calcine for 3 hours to obtain a sulfur-modified support.

[0077] (2) Loading platinum

[0078] According to the mass ratio of platinum-containing solute to sulfur-modified support being 0.0005:1, using the impregnation method, mix 1 g of sulfur-modified support with 0.25 mL of Pt(NO 3 ) 2 aqueous solution (concentration 0.002 g / mL), then add 4.75 mL of deionized water and stir, and let it stand at room temperature for 3 hours. Stir the mixture at a water bath temperature of 90 °C, evaporate to dryness, and dry the powdery solid in an oven at 100 o °C for 1 hour. Then heat in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcine for 4 hours to obtain a platinum-containing catalyst.

[0079] Example 9

[0080] Preparation of a platinum-containing catalyst:

[0081] (1) Preparation of the support

[0082] According to the mass ratio of (NH 4 ) 2 SO 4 to ZrO 2 being 0.05:1, weigh 4 g of ZrO 2 powder and 0.2 g of (NH 4 ) 2 SO 4 Mix and grind for about 45 minutes. Heat the mixture in a muffle furnace at a rate of 10 o °C / min to 550 o °C and calcine for 3 hours to obtain a sulfur-modified support.

[0083] (2) Loading platinum

[0084] According to the mass ratio of platinum-containing solute to sulfur-modified support being 0.01:1, using the impregnation method, mix 1 g of sulfur-modified support with 5 mL of Pt(NO 3 ) 2An aqueous solution (concentration 0.002 g / mL) was mixed and stirred, and left standing at room temperature for 3 hours. The mixture was stirred at a water bath temperature of 90 °C, and after evaporation to dryness, the powdery solid was dried in an oven at 100 o °C for 1 hour. Then it was heated in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcined for 4 hours to obtain a platinum-containing catalyst.

[0085] Comparative Example 1

[0086] (1) ZrO 2 was used as the catalyst support.

[0087] (2) According to the mass ratio of the platinum-containing solute to the catalyst support being 0.01:1, by the impregnation method, 1 g of the ZrO 2 support was mixed and stirred with 5 mL of an aqueous solution of Pt(NO 3 ) 2 (concentration 0.002 g / mL), and left standing at room temperature for 3 hours. The mixture was stirred at a water bath temperature of 90 °C, and after evaporation to dryness, the powdery solid was dried in an oven at 100 o °C for 1 hour. Then it was heated in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcined for 4 hours to obtain a catalyst loaded with platinum.

[0088] 1 g of the catalyst was weighed and mixed and ground with about 0.1088 g of (NH 4 ) 2 SO 4 crystals for about 45 minutes, and heated in a muffle furnace at a rate of 10 °C / min to 500 °C and calcined for 4 hours to obtain a sulfate-modified catalyst.

[0089] Comparative Example 2

[0090] 4 g of the ZrO 2 support was immersed in 3 ml of H 2 SO 4 solution (0.5 mol / L), impregnated at room temperature for 12 hours, the solid was collected by centrifugation, and dried in a 100 o °C oven for 5 hours. It was heated in a muffle furnace at a rate of 10 °C / min to 500 °C and calcined for 3 hours to obtain the support.

[0091] According to the mass ratio of the platinum-containing solute to the support being 0.01:1, by the impregnation method, 1 g of the support was mixed with 5 mL of Pt(NO 3 ) 2The aqueous solution (concentration 0.002 g / mL) was mixed and stirred, and then left standing at room temperature for 3 hours. The mixture was stirred at a water bath temperature of 90 °C, and after evaporation to dryness, the powdery solid was dried in an oven at 100 o °C for 1 hour. Then it was heated in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcined for 4 hours to obtain the platinum-loaded catalyst.

[0092] Comparative Example 3

[0093] ZrO 2 was used as the catalyst support.

[0094] According to the mass ratio of the platinum-containing solute to the mass of the catalyst support being 0.01:1, by the impregnation method, 1 g of ZrO 2 support was mixed with 5 mL of Pt(NO 3 ) 2 aqueous solution (concentration 0.002 g / mL), mixed and stirred, and left standing at room temperature for 3 hours. The mixture was stirred at a water bath temperature of 90 °C, and after evaporation to dryness, the powdery solid was dried in an oven at 100 o °C for 1 hour. Then it was heated in a muffle furnace at a rate of 10 o °C / min to 500 o °C and calcined for 4 hours to obtain the platinum-loaded catalyst.

[0095] Performance test:

[0096] The catalysts prepared in the examples and comparative examples were subjected to XRF testing (to obtain the sulfur content in the catalyst) and catalytic performance evaluation testing. The catalytic performance evaluation was carried out in a quartz tube with an inner diameter of 6 mm, the catalyst dosage was 50 mg (60 - 80 mesh), and the raw material gas (0.2 vol% C 3 H 8 + 2 vol% O 2 + 97.8 vol% N 2 ) entered the catalytic bed at a flow rate of 66.6 mL / min, and the space velocity was 80000 mL / g / h. Gas chromatography (Shimadzu GC-2014, equipped with a 30 m × 0.25 mm × 0.25 µm capillary column and an FID detector) was used to detect the propane concentrations at the inlet and outlet. The test results of the propane oxidation performance (relationship between conversion rate and reaction temperature) of the catalyst are shown in Figures 1 - 3 as follows.

[0097] As Figures 1 - 3As shown, compared with Comparative Example 3, the catalysts of Examples 1-9 and Comparative Examples 1-2 were sulfur-modified, improving the catalytic activity. Compared with Comparative Example 1, sulfur modification before platinum loading increased the activity of the catalyst more than sulfur modification after platinum loading in Example 9.

[0098] As Figure 1 shown, the test results of the catalytic activity of the catalysts in Examples 1-4 showed that adding too high or too low sulfate would lead to a decrease in the catalytic activity of the catalyst.

[0099] As Figure 2 shown, when the mass ratio of the platinum-containing solute to the sulfur-modified support was 0.0005:1, the catalytic activity of the platinum-containing catalyst increased with the increase of the platinum loading. When the mass ratio of the platinum-containing solute to the sulfur-modified support was 0.005:1, the catalytic activity of the platinum-containing catalyst reached the highest. With the increase of the platinum loading, the catalytic activity of the platinum-containing catalyst no longer increased.

[0100] As Figure 3 shown, the catalytic activities of the platinum-containing catalysts in Examples 1 and 9 were close.

[0101] The catalysts prepared in Examples 1-4, Example 9 and Comparative Examples 1-2 were subjected to Pt 4f XPS testing, and the test results are as Figure 3 shown in Table 1.

[0102] Table 1 Summary table of the T 90 , S content and Pt 0 proportion of the catalysts in the examples and comparative examples.

[0103] catalyst <![CDATA[T 90 / o C]]> <![CDATA[S content / mmol·g -1 > <![CDATA[Pt 0 Ratio / %]]> Example 1 220 0.16 44.7 Example 2 200 0.34 59.1 Example 3 210 0.43 49.2 Example 4 250 0.98 41.4 Example 5 200 0.31 — Example 6 210 0.36 — Example 7 220 0.32 — Example 8 260 0.32 — Example 9 210 0.28 45.6 Comparative Example 1 250 0.19 30.8 Comparative Example 2 220 0.05 34.5

[0104] T 90 is Figure 1 , Figure 2 and Figure 3 the lowest reaction temperature corresponding to a catalyst conversion rate greater than 90% in 0 , and the Pt 0 proportion is the proportion of Pt

[0105] As Figures 1 - 3 shown, the propane catalytic oxidation performance of the catalyst in Example 2 was the best, T 90 = 200 o °C, and the S content was 0.34 mmol·g -1 . As shown in Table 1, by observing the S content and Pt 0 proportion in Examples 1-4, it can be found that Pt 0The proportion first increases and then decreases with the increase of S content. When the S content is 0.34 mmol·g -1 , the proportion of Pt 0 is the largest, and Pt 0 is the key active site for propane adsorption and the activation of its C-H bond. Therefore, the result that the proportion of Pt 0 is the largest in the catalyst of Example 2 is consistent with its best propane catalytic performance.

[0106] At a temperature of 200 °C, using the same method as the catalyst performance test, the stability of the catalytic activity of the platinum-containing catalyst prepared in Example 2 was tested, and the obtained results are as Figure 5 shown.

[0107] As Figure 5 shown, it can be found that the propane conversion rate of the catalyst in Example 2 has good stability with the increase of reaction time.

[0108] Finally, compared with Comparative Examples 1-3, the platinum-containing catalyst prepared in Example 2 of the present invention not only has a simpler preparation method, but also achieves better propane catalytic performance under the condition of a lower Pt loading.

[0109] The above embodiments only represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

1. A method for preparing a platinum-containing catalyst, characterized in that: The following steps are involved: S1: preparing a carrier: mixing a zirconium-containing compound and (NH4)2SO4, grinding, and calcining for the first time to obtain a sulfur-modified carrier; S2 loading platinum: the platinum-containing solution and the sulfur-modified carrier are mixed evenly, heated to completely evaporate the solvent, dried, and calcined for the second time to obtain a platinum-containing catalyst.

2. The method for preparing a platinum-containing catalyst according to claim 1, characterized in that: In the step S1, the zirconium-containing compound includes ZrOCO3.

3. The method for preparing a platinum-containing catalyst according to claim 2, characterized in that: In the step S1, the mass ratio of the (NH4)2SO4 to the ZrOCO3 is 0.025-0.2:

1.

4. The method for preparing a platinum-containing catalyst according to claim 1, characterized in that: In the step S1, the temperature control range of the first calcination is 500-600°C, and the calcination time is 2-4h.

5. The method for preparing a platinum-containing catalyst according to claim 1, characterized in that: In the step S2, the platinum-containing solution includes an aqueous solution of platinum nitrate.

6. The method for preparing a platinum-containing catalyst according to claim 1, characterized in that: In the step S2, the ratio of the mass of the platinum-containing solute in the platinum-containing solution to the mass of the sulfur-modified support is 0.0005-0.02:

1.

7. The method for preparing a platinum-containing catalyst according to claim 3, characterized in that: In the step S1, the mass ratio of the (NH4)2SO4 to the ZrOCO3 is 0.05:1; in the step S2, the mass ratio of the solute in the platinum-containing solution to the mass of the sulfur-modified support is 0.01:

1.

8. The method for preparing a platinum-containing catalyst according to claim 1, characterized in that: In the step S2, the temperature of the second calcination is controlled in the range of 450-550°C, and the calcination time is 3-5h.

9. A platinum-containing catalyst, characterized in that The method is prepared according to any one of claims 1 to 8.

10. An application of a platinum-containing catalyst, characterized in that: The platinum-containing catalyst as claimed in claim 9 is used to catalyze the combustion of volatile organic compounds.

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