A catalyst support for petrochemicals, silica, and its preparation method.

Abstract

This invention discloses silica as a catalyst support for petrochemicals and its preparation method, belonging to the field of catalyst technology. The steps are as follows: S1, mixing silica precursor and acidic solution, stirring, adjusting the pH of the system, and reacting for a period of time to obtain silica gel; S2, impregnating the silica gel synthesized in step S1 with an alkali metal inorganic salt solution under ultrasonic assistance; S3, washing the impregnated silica with water, gradient drying, and calcining in an oxygen-containing atmosphere to obtain a silica catalyst support. This product is suitable for reaction catalysis in various scenarios in the petrochemical field. The silica synthesized at the source and the unique impregnation and pore-expansion technology endow the silica with controllable morphology, multi-level channels, and a wider range of pore size adjustment, giving the silica support a larger specific surface area than previous studies. It can efficiently adsorb catalysts without destroying the activity of the catalyst itself, maintain the stability of the supported catalyst, and improve catalytic efficiency.

Description

Technical Field

[0001] This invention belongs to the field of catalyst technology, specifically relating to a silica catalyst support with a controllable pore structure and its preparation method, namely, a method for preparing a silica support with high specific surface area, controllable surface morphology, multi-level pores and high mechanical strength by in-situ synthesis of silica and structural reshaping. Background Technology

[0002] Besides its indiscriminate use as a catalyst in gas-phase synthesis reactions such as carbon disulfide and acetaldehyde, silica is also widely used as a catalyst support in various reaction processes, including polymerization, catalytic hydrogenation, and catalytic cracking, due to its excellent chemical and thermal stability, designable pore structure, specific surface area, surface modification capabilities, and superior metal dispersion and anchoring abilities. High-performance supports are key to improving catalyst dispersibility, selectivity, catalytic activity, and stability.

[0003] However, the commonly used methods for preparing silica catalyst supports in industry mainly include physical processing, hydrothermal processing, and impregnation. These methods have obvious limitations. They are mainly manifested in the following aspects: (1) Physical grinding and other means cannot effectively construct internal channels of silica; (2) The template method for creating pores is costly and complex, and its advantages are not obvious in large-scale production; (3) The support prepared by the mainstream hydrothermal method has relatively rough process control, and the support usually has a small pore size, making it difficult to meet the requirements of efficient mass transfer and high specific surface area of ​​macromolecular reactants and products; (4) The existing impregnation method generally adopts a single alkali metal salt impregnation and simple heat treatment with a wide range of process conditions, resulting in small product pore size, large particle size, small effective surface area, and uneven distribution of surface acid and alkali sites. This leads to uneven loading of active components, easy shedding, low mass transfer efficiency, and even structural collapse and deactivation in practical applications, especially in industrial reactors with high temperature, high pressure, and fluid shear force (such as fluidized beds), which restricts the catalytic efficiency and long-term operation of the device. Currently, the core preparation technology for high-performance silica carriers for petrochemical catalysis, which simultaneously possess high specific surface area, suitable mesoporous composite structure, high mechanical strength, and excellent stability, is still mainly controlled by foreign companies. Domestic products are unable to meet the needs of high-end applications, making the need for domestic substitution extremely urgent.

[0004] Therefore, developing a silica support preparation technology that can precisely control the support structure from the source, has a high specific surface area, is suitable for multi-level channels and excellent mechanical strength, and is simple in process and suitable for industrial production is of great significance for solving the problem of domestic dependence on imports for high-end silica supports and promoting the localization of key materials for petrochemical catalysts in my country. Summary of the Invention

[0005] This invention addresses the shortcomings of existing technologies by providing a silica catalyst support with a controllable pore structure and its in-situ construction method. This method, through a synergistic process of "source synthesis-structural reshaping-performance enhancement," resolves the technical contradictions inherent in traditional methods of simultaneously achieving high specific surface area, controllable multi-level pores, and high mechanical strength. This results in a silica support with excellent performance, good consistency, and suitability for large-scale industrial applications. This aims to promote the large-scale domestic production and independent application of core materials, achieve breakthroughs in subdivided materials innovation, and ultimately benefit the market and R&D enterprises across the supply chain in more fields.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A method for preparing silica, a catalyst support for petrochemical applications, includes the following steps: Step S1: Mix the silica precursor and acidic solution and stir. Adjust the pH of the system and react for a period of time to obtain silica gel. Step S2: The silica gel synthesized in step S1 is subjected to aging and impregnation treatment with an alkali metal inorganic salt solution under ultrasonic assistance. Step S3 involves washing the impregnated silica with water, gradient drying, and calcining in an oxygen-containing atmosphere to obtain a silica catalyst support.

[0007] In the preparation method described above, the silica precursor in step S1 is sodium silicate, the acidic solution is an inorganic acid solution selected from at least one of sulfuric acid, hydrochloric acid, nitric acid, hydrofluoric acid, hydrobromic acid, hydroiodic acid, iodic acid, periodic acid, and perchloric acid, the concentration of the inorganic acid is 30%-75 wt%, the reaction temperature is ≤80°C, the reaction time is 5-30 h, and the pH of the system is adjusted to 3.5-4.5.

[0008] In the preparation method described above, the alkali metal inorganic salt solution in step S2 includes a mixed solution of potassium salt solution and sodium salt solution, and the ultrasonic frequency is 40-60 kHz.

[0009] In the preparation method described above, the mass of the alkali metal inorganic salt is 15-45% of the mass of the silica gel matrix raw material.

[0010] In the preparation method described above, the potassium salt solution includes one or more mixed aqueous solutions of potassium sulfate, carbonate, nitrate, and hydrochloride; the sodium salt solution includes one or more mixed aqueous solutions of sodium sulfate, carbonate, nitrate, and hydrochloride; and the molar ratio of potassium ions to sodium ions in the alkali metal inorganic salt solution is 1:1 to 1:3.

[0011] In the preparation method described above, Na is used in step S2. + -k +During the aging and impregnation treatment of silica gel with composite inorganic salt solution, the impregnation temperature is 50-80℃ and the impregnation time is 2-4h.

[0012] In the preparation method described above, the drying temperature in step S3 is 150-200℃, and the drying time is 3-5h; the calcination atmosphere is air or pure oxygen, the calcination temperature is 300-600℃, and the calcination time is 2-5h.

[0013] In the preparation method described above, the calcination procedure in step S3 is as follows: calcination is carried out in an air atmosphere at a heating rate of 2-10℃ / min.

[0014] In the preparation method described above, the gradient drying temperature program in step S3 is as follows: maintain at 80℃-100℃ for 0.5-1h, and then increase to the drying temperature at a rate of 5℃ / min.

[0015] The catalyst support silica prepared by the above method has a silica particle size of 5-80 μm, a specific surface area of ​​200-800 m² / g, and a specific pore volume of 0.3-3.0 mL / g.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention does not simply combine existing processes, but rather achieves precise construction of the carrier structure from scratch and from existing structure to optimal structure through a synergistic process. Unlike directly purchasing commercially available silica for modification, this invention uses sodium silicate as a silica precursor to synthesize the silica matrix in situ. This step, by controlling the type and concentration of acid, the feeding rate, and the reaction pH, allows for preliminary regulation of the primary morphology and initial pore network of the carrier, laying the structural foundation for subsequent deep modification and providing greater flexibility in the initial design of the process.

[0017] A self-made silica matrix was impregnated using a potassium-sodium composite salt solution and ultrasonic-assisted dispersion. The synergistic effect of potassium and sodium ions with different ionic radii within the pores, combined with ultrasonic-enhanced mass transfer, enabled uniform and controllable erosion and pore expansion of the silica pore walls, effectively avoiding pore collapse or excessive dissolution that is easily caused by conventional alkaline treatment.

[0018] By combining precise gradient drying and calcination, a stable mesoporous interconnected pore network was effectively constructed. This structure provides a high specific surface area (stable at 400 μm²). 2 (Above / g) to load a large number of active centers, while ensuring smooth diffusion of macromolecular chains in the polymerization reaction and improving the medium transport capacity.

[0019] The catalyst support prepared by this invention has optimized surface acidity and alkalinity, which is more conducive to the chemical anchoring of chromium-based, Ziegler-Natta-based, molybdenum-based, and metallocene-based catalysts, thus improving loading stability. The special calcination atmosphere helps to enhance the skeletal strength of the catalyst support, thereby improving wear resistance and service life under harsh production processes.

[0020] By combining the composition control of composite salt solutions, physical field assistance, and programmed heat treatment, a synergistic and controllable preparation process is formed. The process parameters are well-defined, the operation is simple, the reproducibility is good, energy is saved, and the cost is lower. At the same time, it can overcome the shortcomings of existing technologies, such as wide process conditions and poor product consistency, and is more conducive to large-scale and stable production.

[0021] This method eliminates the need for template agents and specialized equipment such as hydrothermal autoclaves. The preparation process, based on conventional operations, features low energy consumption, well-defined process parameters, and good reproducibility. Sodium silicate, the raw material, is widely available and inexpensive. The entire process for preparing the silica catalyst support is domestically developed and simple to operate, giving this technology significant cost advantages and potential for large-scale production.

[0022] The silica catalyst support prepared in this application is suitable for catalytic reactions in various scenarios in the petrochemical industry. The silica synthesized from the source and the unique impregnation and pore-expansion technology endow the silica with controllable morphology, hierarchical channels, and a wider range of pore size adjustment, giving the silica support a larger specific surface area than previous studies. The surface morphology and pore structure, flexibly customized according to the application scenario, enable it to exhibit excellent performance in the petrochemical field, efficiently adsorbing catalysts without damaging the catalyst's activity, maintaining the stability of the supported catalyst, and improving catalytic efficiency. Furthermore, in addition to the advantage of a wide range of raw material sources, compared with technologies using organic solvents such as toluene, this invention constructs a green, all-aqueous synthesis route. This not only avoids the toxicity, safety, and environmental pollution problems associated with organic solvents but also simplifies the post-processing steps, reduces overall production costs, and enables large-scale mass production while maintaining a cost advantage, demonstrating promising commercial application prospects. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below. The specific embodiments listed below are merely descriptions of the principles and features of the present invention, and the examples are only for explaining the present invention and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] A method for preparing silica, a catalyst support for petrochemical applications, includes the following steps: Step 1: Select sodium silicate as the silica precursor. Sodium silicate is a commercially available product. Step 2: Dilute the acidic solution with purified water and add it to the reaction vessel. Under stirring conditions, add sodium silicate, the precursor of silica, and adjust the pH of the system to induce a dehydration condensation reaction to synthesize silica gel. The acidic solution is an inorganic acid selected from at least one of sulfuric acid, hydrochloric acid, nitric acid, hydrofluoric acid, hydrobromic acid, hydroiodic acid, iodic acid, periodic acid, and perchloric acid. The concentration of the inorganic acid is 30%-75%, the reaction temperature is ≤80°C, the reaction time is 5-30h, and the pH of the system is adjusted to 3.5-4.5. Step 3: The silica gel synthesized in Step 2 is subjected to ultrasonic-assisted impregnation with an alkali metal inorganic salt solution. Step four: The silica obtained after the pretreatment in step three is washed with water, dried in a gradient, and calcined in an oxygen-containing atmosphere to obtain a silica catalyst support.

[0025] In step four of this embodiment, the porous silica matrix obtained is amorphous or spherical with a particle size of 5-80 μm.

[0026] In step three of this embodiment, the alkali metal inorganic salt solution is a potassium-sodium inorganic salt solution, specifically a mixture of one or more of sodium and potassium sulfates, carbonates, nitrates, and hydrochlorides. The molar ratio of potassium ions to sodium ions in the composite salt solution is 1:1 to 1:3. The immersion treatment temperature is 50-80℃, and the time is 2-4 hours. The ultrasonic-assisted frequency is 40-60 kHz.

[0027] In step three of this embodiment, the alkali metal inorganic salt is 15-45% by weight of the porous silica microsphere matrix.

[0028] In step four of this embodiment, the gradient drying temperature is 150-200℃, and the heating program is as follows: maintain at 80-100℃ for 0.5-1h, and then increase to the drying temperature at a rate of 5℃ / min, with a drying time of 3-5h.

[0029] In step four, the raw materials are roasted in an air atmosphere or a pure oxygen atmosphere at a temperature of 300-600℃, with a heating rate of 2-10℃ / min and a roasting time of 2-5h.

[0030] Example 1: A method for preparing silica, a catalyst support for petrochemical applications, includes the following steps: Step 1: Select sodium silicate as the silicon dioxide precursor; Step 2: Dilute the acidic solution with deionized water and add it to the reaction vessel. Under stirring conditions, add sodium silicate precursor and adjust the pH of the system to induce a dehydration condensation reaction to synthesize silica gel. The inorganic acid used in the pH adjustment process is sulfuric acid with a concentration of 75 wt%. Adjust the pH of the system to 4.5, control the acid treatment temperature below 80°C, and treat for 20 hours. Step 3: The silica synthesized in Step 2 is subjected to ultrasonic-assisted impregnation with an alkali metal inorganic salt solution; K + -Na + The inorganic salt solution is a mixture of aqueous solutions of potassium sulfate and sodium sulfate, wherein the molar ratio of potassium ions to sodium ions in the composite salt solution is 1:2; the immersion treatment is performed at a temperature of 50°C for 3 hours; the ultrasonic-assisted frequency is 40-60 kHz; and the alkali metal inorganic salt is 30% by weight of the porous silica matrix.

[0031] Step four involves washing the silica obtained after the pretreatment in step three with water, performing gradient drying, and calcining in an oxygen-containing atmosphere to obtain a silica catalyst support. The gradient drying temperature is 200℃, and the heating program is as follows: maintain at 80℃ for 30 min, then increase to 200℃ at a rate of 5℃ / min, with a drying time of 3 h. The raw material is calcined in a pure oxygen atmosphere at a heating rate of 10℃ / min, a calcination temperature of 600℃, and a calcination time of 2 h.

[0032] Example 2 A method for preparing silica, a catalyst support for petrochemical applications, includes the following steps: Step 1: Select sodium silicate as the silicon dioxide precursor; Step 2: Dilute the acidic solution with deionized water and add it to the reaction vessel. Under stirring conditions, add sodium silicate precursor and adjust the pH of the system to 3.5 to induce dehydration condensation reaction and synthesize silica gel. The inorganic acid used to adjust the pH of the system is hydrochloric acid with a concentration of 45 wt%. The acid treatment temperature is controlled below 80°C and the treatment time is 25 h.

[0033] Step 3: The silica synthesized in Step 2 is subjected to ultrasonic-assisted impregnation with an alkali metal inorganic salt solution. The potassium-sodium inorganic salt solution is an aqueous mixture of potassium sulfate and sodium carbonate, wherein the molar ratio of potassium ions to sodium ions in the composite salt solution is 1:3. The impregnation treatment is carried out at a temperature of 80°C for 4 hours. The ultrasonic frequency is 40-60 kHz. The alkali metal inorganic salt constitutes 30% by weight of the porous silica matrix.

[0034] Step four: The silica obtained after the pretreatment in step three is washed with water, subjected to gradient drying, and calcined in an oxygen-containing atmosphere to obtain a silica catalyst support. The gradient drying temperature is 150℃, and the heating program is as follows: hold at 80℃ for 60 min, then increase to 150℃ at a rate of 5℃ / min, and the drying time is 5 h.

[0035] The raw materials were roasted in a pure oxygen atmosphere at a heating rate of 10℃ / min, a roasting temperature of 500℃, and a roasting time of 2h.

[0036] Example 3 A method for preparing silica, a catalyst support for petrochemical applications, includes the following steps: Step 1: Select sodium silicate as the silicon dioxide precursor; Step 2: Dilute the acidic solution with deionized water and add it to the reaction vessel. Under stirring conditions, add sodium silicate precursor and adjust the pH of the system to induce dehydration condensation reaction to synthesize silica gel. Adjust the pH of the system to 4.5. The inorganic acid used is sulfuric acid with a concentration of 75 wt%. The acid treatment temperature is controlled below 80°C and the treatment time is 30 h.

[0037] Step 3: The silica synthesized in Step 2 is subjected to ultrasonic-assisted impregnation with an alkali metal inorganic salt solution; the potassium-sodium inorganic salt solution is an aqueous mixture of potassium sulfate and sodium chloride, wherein the molar ratio of potassium ions to sodium ions in the composite salt solution is 1:1; the impregnation treatment is carried out at a temperature of 50°C for 3 hours; the ultrasonic assistance frequency is 40-60 kHz. The alkali metal inorganic salt constitutes 30% by weight of the porous silica matrix.

[0038] Step four involves washing the silica obtained after the pretreatment in step three with water, performing gradient drying, and calcining in an oxygen-containing atmosphere to obtain a silica catalyst support. The gradient drying temperature is 200℃, and the heating program is as follows: maintain at 80℃ for 30 min, then increase to 150℃ at a rate of 5℃ / min, with a drying time of 4 h. The raw material is calcined in a pure oxygen atmosphere at a heating rate of 10℃ / min, a calcination temperature of 600℃, and a calcination time of 2 h.

[0039] Example 4 A method for preparing silica, a catalyst support for petrochemical applications, includes the following steps: Step 1: Select sodium silicate as the silicon dioxide precursor; Step 2: Dilute the acidic solution with deionized water and add it to the reaction vessel. Under stirring conditions, add sodium silicate precursor and adjust the pH of the system to induce dehydration condensation reaction to synthesize silica gel. During the pH adjustment process, the inorganic acid used is sulfuric acid with a concentration of 75 wt%. The acid treatment temperature is controlled below 100°C and the treatment time is 20 hours.

[0040] Step 3: The silica synthesized in Step 2 is subjected to ultrasonic-assisted impregnation with an alkali metal inorganic salt solution. The potassium-sodium inorganic salt solution is a mixture of aqueous solutions of potassium sulfate and sodium sulfate, wherein the molar ratio of potassium ions to sodium ions in the composite salt solution is 0.5:1. The impregnation treatment is carried out at a temperature of 50°C for 2 hours. The ultrasonic frequency is 40-60 kHz. The alkali metal inorganic salt constitutes 30% by weight of the porous silica matrix.

[0041] Step four involves washing the silica obtained after the pretreatment in step three with water, performing gradient drying, and calcining in an oxygen-containing atmosphere to obtain a silica catalyst support. The gradient drying temperature is 200℃, and the heating program is as follows: maintain at 80℃ for 30 min, then increase to 200℃ at a rate of 5℃ / min, with a drying time of 3 h. The raw material is calcined in a pure oxygen atmosphere at a heating rate of 5℃ / min, at a calcination temperature of 400℃, for a calcination time of 5 h.

[0042] Comparative Example 1 In this comparative example, commercially available silica (particle size 40-120 mesh (125μm~425μm), specific pore volume 1.0-1.2mL / g, specific surface area 330-400m²) was directly used in alkali metal inorganic salt solution. 2 The alkali metal inorganic salt solution used was impregnated with water, washed, gradient dried and calcined (with a pore size of 2-50 nm). The remaining operations were the same as in Example 1.

[0043] Comparative Example 2 This comparative example is basically the same as Example 1, except that the alkali metal inorganic salt solution used in step three is an aqueous solution of sodium sulfate, and the sodium sulfate solution contains Na... + Na in the potassium-sodium inorganic salt solution of Example 1 + and K + The molar concentrations are the same.

[0044] Comparative Example 3 This comparative example is basically the same as Example 1, except that the alkali metal inorganic salt solution used in step three is an aqueous solution of potassium sulfate, and the potassium sulfate solution has a K0 content of 100%. + Na in the potassium-sodium inorganic salt solution of Example 1 + and K + The molar concentrations are the same.

[0045] Comparative Example 4 Composite salt impregnation without ultrasonic assistance; This comparative example is basically the same as Example 1, except that ultrasonic assistance is not used in step three of this comparative example.

[0046] Comparative Example 5 This comparative example is basically the same as Example 1, except that step four in this comparative example is conventional drying, not gradient drying.

[0047] The key indicators such as pore size, specific surface area, and pore volume of the silica prepared in Examples 1-4 and Comparative Examples 1-5 were tested using BET and other testing methods. The test results are shown in Table 1.

[0048] Table 1. Performance testing of silica prepared in the examples and comparative examples.

[0049] This invention selects K + / Na + The molar ratio of 1:1 to 1:3 is based on the completely different action mechanisms of the two ions on the silica network, and the result of optimal channel control is achieved through synergistic effect.

[0050] In the comparative example, the selection of silicon source and the silica gel synthesis stage were omitted, and commercially available silica products were directly used. The catalyst support was prepared only through subsequent ultrasonic-assisted impregnation and drying. This approach cannot design and control the pore structure from the source, and the resulting support is difficult to achieve simultaneously high specific surface area, large pore size, and high pore volume. Crucially, the small pore size prevents the metal catalyst from effectively entering and firmly anchoring within the pores, significantly reducing adsorption loading efficiency. In contrast, this invention, through pre-construction of pores during the gel synthesis stage, achieves synergistic optimization of pore size and pore volume, ensuring efficient loading and stable dispersion of the metal active component. + The particles have a smaller radius and tend to enter the silica network and interstitial vacancies, making the silica framework more compact, thereby achieving fine-tuning of the pore size while enhancing the framework strength. K + The particle radius is relatively large, which can significantly expand the pores by breaking the silicon-oxygen bonds inside the silicon dioxide. However, breaking the chemical bonds will affect the mechanical strength of the silicon dioxide, making it easy to break under negative pressure.

[0051] By analyzing Na + (Densification-dominated) and K + The ratio of (phase separation dominant) can precisely balance these two effects, thereby enabling the customization of the pore structure, achieving significant pore enlargement while maintaining a narrow pore size distribution and good mechanical strength.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing silica, a catalyst support for petrochemical applications, characterized in that, Includes the following steps: Step S1: Mix the silica precursor and acidic solution and stir. Adjust the pH of the system and react for a period of time to obtain silica gel. Step S2: The silica gel synthesized in step S1 is subjected to aging and impregnation treatment with an alkali metal inorganic salt solution under ultrasonic assistance. Step S3 involves washing the impregnated silica with water, gradient drying, and calcining in an oxygen-containing atmosphere to obtain a silica catalyst support.

2. The method for preparing silica as a catalyst support in petrochemicals according to claim 1, characterized in that: In step S1, the silica precursor is sodium silicate, the acidic solution is an inorganic acid solution selected from at least one of sulfuric acid, hydrochloric acid, nitric acid, hydrofluoric acid, hydrobromic acid, hydroiodic acid, iodic acid, periodic acid, and perchloric acid, the concentration of the inorganic acid is 30%-75% w, the reaction temperature is ≤80°C, the reaction time is 5-30 h, and the pH of the system is adjusted to 3.5-4.

5.

3. The method for preparing silica as a catalyst support in petrochemicals according to claim 1, characterized in that: The alkali metal inorganic salt solution in step S2 includes a mixture of potassium salt solution and sodium salt solution, and the ultrasonic frequency is 40-60 kHz.

4. The method for preparing silica, a catalyst support for petrochemical applications, according to claim 3, is characterized in that: The mass of the alkali metal inorganic salt is 15-45% of the mass of the silica gel matrix raw material.

5. The method for preparing silica, a catalyst support for petrochemical applications, according to claim 3, is characterized in that: The potassium salt solution includes one or more mixed aqueous solutions of potassium sulfate, carbonate, nitrate, and hydrochloride; the sodium salt solution includes one or more mixed aqueous solutions of sodium sulfate, carbonate, nitrate, and hydrochloride; the molar ratio of potassium ions to sodium ions in the alkali metal inorganic salt solution is 1:1 to 1:

3.

6. The method for preparing silica as a catalyst support in petrochemicals according to claim 3, characterized in that: Na + -k + In the aging and impregnation process of the silica gel by the composite inorganic salt solution, the temperature for impregnation is 50-80℃ and the impregnation time is 2-4h.

7. The method for preparing silica as a catalyst support in petrochemicals according to claim 1, characterized in that: The drying temperature in step S3 is 150-200℃, and the drying time is 3-5h; the calcination atmosphere is air or pure oxygen, the calcination temperature is 300-600℃, and the calcination time is 2-5h.

8. The method for preparing silica, a catalyst support for petrochemical applications, according to claim 7, is characterized in that: The roasting procedure in step S3 is as follows: roasting is carried out in an air atmosphere with a heating rate of 2-10℃ / min.

9. The method for preparing silica as a catalyst support in petrochemicals according to claim 7, characterized in that: The gradient drying temperature program in step S3 is as follows: maintain the temperature at 80℃-100℃ for 0.5-1h, and then increase it to the drying temperature at a rate of 5℃ / min.

10. The catalyst support silica prepared by the method according to any one of claims 1-9, characterized in that: The silica particles have a diameter of 5-80 μm, a specific surface area of ​​200-800 m² / g, and a specific pore volume of 0.3-3.0 mL / g.

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