High-activity adjustable solid catalyst as well as preparation method and application thereof
By preparing Cu1-xCoxFe2O4 spinel-type ferrite catalyst, the problems of poor selectivity and high cost in the preparation of phenolic antioxidants were solved, and efficient, low-temperature ortho-alkylation reaction was achieved, expanding the application field of phenolic antioxidants.
Patent Information
- Application Number
- CN202511199095.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-26
- Publication Date
- 2025-12-09
AI Technical Summary
Existing methods for preparing phenolic antioxidants suffer from poor selectivity, high investment costs, and are prone to reactor corrosion and byproduct formation. Furthermore, there is a lack of efficient and convenient catalysts.
A spinel-type ferrite catalyst, Cu1-xCoxFe2O4, was prepared by hydrothermal crystallization reaction using hexadecyltrimethylammonium bromide and ferric chloride hexahydrate as raw materials, combined with transition metal salts such as cobalt chloride hexahydrate or copper chloride dihydrate. The catalyst structure and metal distribution were optimized.
This method improves the selectivity and catalytic activity of ortho-alkylation of aromatic compounds, reduces the reaction temperature, and enables the large-scale preparation and application of phenolic antioxidants, overcoming the shortcomings of traditional methods.
Smart Images
Figure CN121082282A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of catalyst preparation technology, specifically to a highly active tunable solid catalyst, its preparation method, and its application. Background Technology
[0002] Phenolic antioxidants are a class of compounds containing one or more phenolic hydroxyl groups and exhibiting antioxidant properties. They are characterized by strong antioxidant activity, wide applicability, multifunctionality, and commercial availability, which makes phenolic antioxidants occupy a key position in the field of antioxidants.
[0003] There are many routes for preparing phenolic antioxidants. More than 60% of manufacturers both domestically and internationally use the p-cresol method, which involves using concentrated sulfuric acid or concentrated phosphoric acid as a catalyst in the presence of alumina as a dehydrating agent to alkylate p-cresol with isobutylene. The phenolic antioxidant is then prepared through processes such as catalyst separation, distillation, or purification. Some manufacturers directly use a mixture of (m- and p-)cresols produced by petrochemical or coal chemical processes as raw materials to react with isobutylene to prepare phenolic antioxidants. In 1956, Bayer and other companies in Germany invented the aluminum phenolate catalyst, opening a new route for synthesizing phenolic antioxidants and making them a major global supplier of phenolic antioxidants. However, the above methods for preparing phenolic antioxidants all have disadvantages such as poor selectivity, high investment costs, easy reactor corrosion, and the formation of byproducts. Therefore, developing a more efficient and convenient catalyst has become crucial for the large-scale preparation of phenolic antioxidants and for capturing the phenolic antioxidant market. Summary of the Invention
[0004] To address the aforementioned problems, this invention provides a highly active tunable solid catalyst, its preparation method, and its application. The specific solution of this invention is as follows: A method for preparing a highly active tunable solid catalyst includes the following steps: mixing and stirring hexadecyltrimethylammonium bromide, ferric chloride hexahydrate, and water at a solid-liquid ratio of (1~3):(1~3):(30~40) to prepare a mixed solution; then impregnating a transition metal salt alkali into the prepared mixed solution, followed by a hydrothermal crystallization reaction to obtain the highly active tunable solid catalyst.
[0005] More preferably, the aforementioned transition metal salt is one or more of the metal salts containing Co or Cu.
[0006] More preferably, the aforementioned transition metal salt is one or both of cobalt chloride hexahydrate and copper chloride dihydrate.
[0007] More preferably, the amount of the aforementioned transition metal salt added is 31.5% to 44.0% of the mass of ferric chloride hexahydrate.
[0008] More preferably, the above-mentioned transition metal salt alkali impregnation in the prepared mixed solution refers to mixing the metal salt with the mixed solution, and then slowly adding a 5% sodium hydroxide aqueous solution dropwise to the mixed solution to control the pH of the mixed solution to 9-11.
[0009] More preferably, the process parameters for the above-mentioned hydrothermal crystallization reaction are: heating to 150~160℃, heating rate of 10~20℃ / min, and heat treatment for 60~72h.
[0010] Based on the same technical concept, the present invention provides a highly active tunable solid catalyst, which is prepared by any of the above-described methods for preparing a highly active tunable solid catalyst.
[0011] More preferably, the chemical formula of the above catalyst is Cu. 1-x Co x Fe2O4; wherein the loading of transition metals Co and / or Cu is 13~25wt%.
[0012] Based on the same technical concept, this invention provides an application of a highly active tunable solid catalyst, which is applied to the ortho-alkylation of phenols by the above-mentioned method for preparing a highly active tunable solid catalyst.
[0013] More preferably, when the catalyst is applied to the ortho-alkylation of phenols, the reaction conditions are atmospheric pressure, reaction temperature of 80~120℃, and reaction time of 10~12 hours.
[0014] The advantages of this invention compared to the prior art are: This invention obtains Cu through a hydrothermal crystallization reaction using hexadecyltrimethylammonium bromide and ferric chloride hexahydrate as raw materials, and cobalt chloride hexahydrate and copper chloride dihydrate as transition metal salts. 1-x Co x This invention provides a highly active, tunable solid catalyst based on Fe2O4 spinel ferrite. Compared to spinel ferrites prepared by other existing methods, the product obtained in this invention exhibits stronger coupling due to the doping with transition metals. Furthermore, the catalyst structure and the distribution of transition metal elements are more uniform. The metal ions located at the vertices of its octahedral structure are more conducive to reactant adsorption, resulting in stronger selectivity for ortho-alkylation of aromatic compounds and a significant improvement in the catalyst's activity for ortho-alkylation.
[0015] Cu prepared by this invention 1-x Co xFe2O4 spinel-type ferrite nanocatalysts not only exhibit higher selectivity for ortho-alkylation of aromatic compounds, but also overcome most of the shortcomings of traditional methods for preparing phenolic antioxidants. Therefore, this novel catalyst is of great significance not only for the large-scale preparation of phenolic antioxidants, but also for the development of applications in phenolic antioxidant fields such as oil and fat preservatives and fuel anti-gumming agents, with extremely broad application prospects and substantial economic benefits.
[0016] This invention provides an application of a highly active tunable solid catalyst, which utilizes a tunable solid acidity catalyst (Cu) supported on a metal salt. 1-x Co x Fe2O4 spinel ferrite is used for the efficient ortho-alkylation reaction of aromatic molecules, featuring low reaction temperature (≤100℃), high ortho-selectivity, and excellent recyclability. The highly active tunable solid catalyst supported on metal salts prepared in this invention is applied to the production of hindered phenolic antioxidants from phenolic substances. Under the synergistic effect of the tunable solid acid and transition metals Co and Cu, alkyl groups can attack the less sterically hindered ortho-hydroxyl groups, thereby efficiently completing the selective cleavage of CH bonds and the formation of C / C bonds during ortho-alkylation, achieving the goal of producing hindered phenolic antioxidants from phenolic substances. The Lewis acidity is determined based on the nearby easily reducible ion (Cu). 2+ ) or non-reducible ions (Co) 2 + It changes with the changes in ). Attached Figure Description
[0017] Figure 1 The left figure is a SEM morphology image of the catalyst of Embodiment 1 of the present invention, and the right figure is an EDX elemental content image of the catalyst of Embodiment 1 of the present invention. Figure 2 The left figure is a SEM morphology image of the catalyst of Embodiment 2 of the present invention, and the right figure is an EDX elemental content image of the catalyst of Embodiment 2 of the present invention. Figure 3 The left figure is a SEM morphology image of the catalyst of Embodiment 3 of the present invention, and the right figure is a graph of the EDX elemental content of the catalyst of Embodiment 3 of the present invention. Figure 4 The left figure is a SEM morphology image of the catalyst in Embodiment 4 of the present invention, and the right figure is a graph of the EDX elemental content of the catalyst in Embodiment 4 of the present invention. Figure 5 The left figure is a SEM morphology image of the catalyst of Embodiment 5 of the present invention, and the right figure is an EDX elemental content image of the catalyst of Embodiment 5 of the present invention. Figure 6 The left figure is a SEM morphology image of the catalyst of Embodiment 6 of the present invention, and the right figure is a graph of the EDX elemental content of the catalyst of Embodiment 6 of the present invention. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described and illustrated below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments provided by this invention without creative effort are within the scope of protection of this invention. Unless otherwise specified, all embodiments and optional embodiments of this invention can be combined to form new technical solutions.
[0019] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.
[0020] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.
[0021] The present invention provides a method for preparing a highly active tunable solid catalyst, comprising the following steps: mixing and stirring cetyltrimethylammonium bromide and ferric chloride hexahydrate as raw materials to prepare a mixed solution; then impregnating the prepared mixed solution with transition metals Co and Cu as bases, followed by a hydrothermal crystallization reaction to obtain a highly active tunable solid catalyst.
[0022] Furthermore, the specific steps include: preparing a highly active tunable solid catalyst. a1. Weigh out equal masses of hexadecyltrimethylammonium bromide and ferric chloride hexahydrate, dissolve them in a certain amount of distilled water, and stir magnetically for 10-15 minutes. a2. Take a certain amount of metal salts, mix them, and add distilled water to obtain a mixed metal salt solution; a3. Slowly add the mixed metal salt solution to the above mixed solution and stir magnetically for 10-15 minutes; a4. Prepare a certain amount of 5% sodium hydroxide aqueous solution and slowly add it dropwise to the above mixed solution to make the pH of the mixed solution 9-11, and continue stirring for 20-25 minutes; a5. Add the above mixed solution to the reaction vessel for heat treatment at a temperature of 160°C for 72 hours to obtain a solid-liquid mixture. a6. Centrifuge the above solid-liquid mixture, filter, wash with water, and dry the filter cake in an oven at 90°C for 6 hours to obtain a highly active tunable solid catalyst.
[0023] Furthermore, in step a1, the solid-liquid ratio of hexadecyltrimethylammonium bromide, ferric chloride hexahydrate, and water is 1:1:35.
[0024] Further, in step a2, the transition metal salt is one or more metal salts of Co and Cu, and the metal loading is (13-25) wt%.
[0025] Furthermore, in step a5, during heat treatment, the temperature is raised to 160°C at a rate of 10°C / min, and the heat treatment lasts for 72 hours.
[0026] The specific implementation method is as follows: Example 1 A method for preparing a highly active tunable solid catalyst, comprising the following specific steps: (1) Dissolve 1g of cetyltrimethylammonium bromide and 1g of ferric chloride hexahydrate in 35mL of distilled water and stir magnetically for 15min at room temperature to obtain a mixed solution; (2) Dissolve 0.264 g of cobalt chloride hexahydrate and 0.126 g of copper chloride dihydrate in 3 mL of distilled water to obtain a mixed metal salt solution; (3) Slowly add the mixed metal salt solution to the above mixed solution and stir magnetically for 10 minutes; (4) Prepare a certain amount of 5% sodium hydroxide aqueous solution and slowly add it dropwise to the above mixed solution so that the pH of the mixed solution is 10, and continue stirring for 20 minutes; (5) The above mixed solution is added to the reaction vessel for heat treatment at a temperature of 160°C for 72 hours to obtain a solid-liquid mixture. (6) The above solid-liquid mixture was centrifuged, filtered, washed with water, and the filter cake was dried in an oven at 90°C for 6 hours to obtain a highly active tunable solid catalyst with a Co / Cu loading of 21.2%, i.e., Cu 0.4 Co 0.6 Fe2O4. Its SEM image is as follows: Figure 1 As shown.
[0027] Example 2 The difference from Example 1 is that the amounts of cobalt chloride hexahydrate and copper chloride dihydrate added were 0 g and 0.315 g, respectively, to prepare a highly active tunable solid catalyst with a Co / Cu loading of 13.5%, namely CuFe2O4. The SEM image is shown below. Figure 2 As shown.
[0028] Example 3 The difference from Example 1 is that the amounts of cobalt chloride hexahydrate and copper chloride dihydrate added are 0.0880 g and 0.252 g, respectively, to prepare a highly active tunable solid catalyst with a Co / Cu loading of 16.2%, i.e., Cu... 0.8 Co 0.2 Fe2O4, SEM image as follows Figure 3 As shown.
[0029] Example 4 The difference from Example 1 is that the amounts of cobalt chloride hexahydrate and copper chloride dihydrate added are 0.176 g and 0.189 g, respectively, to prepare a highly active tunable solid catalyst with a Co / Cu loading of 18.8%, i.e., Cu... 0.6 Co 0.4 Fe2O4, SEM image as follows Figure 4 As shown.
[0030] Example 5 The difference from Example 1 is that the amounts of cobalt chloride hexahydrate and copper chloride dihydrate added are 0.352 g and 0.0631 g, respectively, to prepare a highly active tunable solid catalyst with a Co / Cu loading of 22.9%, i.e., Cu... 0.2 Co 0.8 Fe2O4, SEM image as follows Figure 5 As shown.
[0031] Example 6 The difference from Example 1 is that the amounts of cobalt chloride hexahydrate and copper chloride dihydrate added were 0.440 g and 0 g, respectively, resulting in a highly active tunable solid catalyst with a Co / Cu loading of 24.2%, namely CoFe2O4. The SEM image is shown below. Figure 6 As shown.
[0032] Comparative Example 1: The difference from Example 1 is that the supporting metal is different; it is Ni, and the amount of nickel chloride hexahydrate added is 0.440g, resulting in a highly active tunable solid catalyst with a Ni loading of 25.1%, namely NiFe2O4.
[0033] Comparative Example 2: The difference from Example 1 is that the supporting metal is different; it is Zn, and the amount of zinc chloride tetrahydrate added is 0.450g, resulting in a highly active tunable solid catalyst with a Zn loading of 27.1%, namely ZnFe2O4.
[0034] The effects of different transition metal contents on the prepared highly active tunable solid catalysts in Examples 1-6 are shown in Table 1.
[0035]
[0036] Application Example 1 The catalysts prepared in Examples 1, 2, 3, 4, 5 and 6 were used in the ortho-alkylation of phenols.
[0037] The catalyst was evaluated under programmed temperature-controlled, high-pressure, mechanically stirred microreactor conditions.
[0038] Using p-cresol and tert-butanol as substrates, the reaction conditions were atmospheric pressure, 100℃, and 12 hours. The substrates were excess p-cresol (50 mmol, approximately 5.407 g) and tert-butanol (8 mL), with a catalyst added of 0.005 g. The catalyst's ability to alkylate aromatic compounds at the ortho-position was evaluated. The reaction results are shown in Table 2.
[0039] The analysis method for ortho-alkylation products was performed using an Agilent 7890 / 5973 quadrupole gas chromatograph / mass spectrometer to analyze the composition of the conversion products. The chromatographic column was a 60m × 0.25mm × 0.25um HP-5MS capillary cross-linked column.
[0040]
[0041] Application Example 2 The catalysts prepared in Examples 1, 2, 3, 4, 5 and 6 were used in ortho-alkylation.
[0042] The catalyst was evaluated under programmed temperature-controlled, high-pressure, mechanically stirred microreactor conditions.
[0043] A mixture of phenols (o-cresol (40%-50%), m-cresol (25%-35%), and p-cresol (<10%)) and tert-butanol was used as the reaction substrates. The reaction conditions were atmospheric pressure, 80℃, and 12 hours. Excess p-cresol (50 mmol, approximately 5.407 g), 8 mL of tert-butanol, and 0.05 g of catalyst were used as the reaction substrates. The catalyst's ability to alkylate aromatic compounds at the ortho-position was evaluated. The reaction results are shown in Table 3.
[0044] The analysis method for ortho-alkylation products was performed using an Agilent 7890 / 5973 quadrupole gas chromatograph / mass spectrometer to analyze the composition of the conversion products. The chromatographic column was a 60m × 0.25mm × 0.25um HP-5MS capillary cross-linked column.
[0045]
[0046] Application Example 3 The catalysts prepared in Examples 1, 2, 3, 4, 5 and 6 were used in ortho-alkylation.
[0047] The catalyst was evaluated under programmed temperature-controlled, high-pressure, mechanically stirred microreactor conditions.
[0048] Using p-cresol and tert-butanol as substrates, the reaction was conducted under ambient pressure at 80°C for 12 hours. The substrates used were excess p-cresol (50 mmol, approximately 5.407 g) and 8 mL of tert-butanol, with a catalyst dosage of 0.05 g. The catalyst's ability to alkylate aromatic compounds at the ortho-position was evaluated. The results are shown in Table 4.
[0049] The analysis method for ortho-alkylation products was performed using an Agilent 7890 / 5973 quadrupole gas chromatograph / mass spectrometer to analyze the composition of the conversion products. The chromatographic column was a 60m × 0.25mm × 0.25um HP-5MS capillary cross-linked column.
[0050]
[0051] Application Example 4 The catalysts prepared in Examples 1, 2, 3, 4, 5 and 6 were used in ortho-alkylation.
[0052] The catalyst was evaluated under programmed temperature-controlled, high-pressure, mechanically stirred microreactor conditions.
[0053] Using p-cresol and tert-butanol as substrates, the reaction conditions were atmospheric pressure, 120℃, and 12 hours. The substrates were excess p-cresol (50 mmol, approximately 5.407 g) and tert-butanol (8 mL), with a catalyst added of 0.05 g. The catalyst's ability to alkylate aromatic compounds at the ortho-position was evaluated. The reaction results are shown in Table 5.
[0054] The analysis method for ortho-alkylation products was performed using an Agilent 7890 / 5973 quadrupole gas chromatograph / mass spectrometer to analyze the composition of the conversion products. The chromatographic column was a 60m × 0.25mm × 0.25um HP-5MS capillary cross-linked column.
[0055]
[0056] Application Comparative Example 1 The ortho-alkylation reaction in Application Example 1 was compared with catalysts prepared with other metals (Comparative Example 1 and Comparative Example 2). With the preparation reaction and reaction conditions remaining unchanged (100°C), the ortho-alkylation selectivity is shown in Table 6. When the supported metals are Ni and Zn, the ortho-alkylation selectivity is less than 50%; when the supported metals are Co or Cu, the ortho-alkylation selectivity exceeds 80%; and when a composite Cu / Co support is used, the ortho-alkylation selectivity is 100%. The comparisons are shown in Table 6.
[0057]
[0058] Application Comparative Example 2 The ortho-alkylation reaction in Application Example 1 is compared with the current reaction for preparing hindered phenols, as shown in Table 7. When an aryl sulfonic acid catalyst is selected, strong acidic conditions are required to achieve an ortho-selectivity of over 95% when the reaction temperature does not exceed 150°C. When an aluminum-based catalyst is used, acidic conditions are required to achieve an ortho-selectivity of over 95% when the reaction temperature is 160°C. However, this application example uses a spinel nanocatalyst, which can prepare hindered phenolic antioxidants at low temperatures (≤100°C) with an ortho-selectivity of up to 100%.
[0059]
[0060] Examples 1, 2, 3, 4, 5, and 6, which use equal amounts of iron-based oxides as supports and load different amounts of metallic Co / Cu on p-methylphenol, demonstrate that Cu... 0.6 Co 0. 4Fe₂O₄ has advantages below 100℃; Cu 1- x Co x Fe2O4 can enable aromatic compounds to undergo ortho-alkylation reactions efficiently.
[0061] The above embodiments only illustrate one or more implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of protection of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.
Claims
1. A method for preparing a highly active tunable solid catalyst, characterized in that, The process includes the following steps: mixing hexadecyltrimethylammonium bromide, ferric chloride hexahydrate, and water in a solid-liquid ratio of (1~3):(1~3):(30~40) to prepare a mixed solution; then impregnating the prepared mixed solution with a transition metal salt base, followed by a hydrothermal crystallization reaction to obtain a highly active tunable solid catalyst.
2. The preparation method according to claim 1, characterized in that, The transition metal salt is one or more of the metal salts containing Co or Cu.
3. The preparation method according to claim 2, characterized in that, The transition metal salt is one or both of cobalt chloride hexahydrate and copper chloride dihydrate.
4. The preparation method according to claim 3, characterized in that, The amount of the transition metal salt added is 31.5% to 44.0% of the mass of ferric chloride hexahydrate.
5. The preparation method according to claim 4, characterized in that, The process of impregnating the transition metal salt in the prepared mixed solution involves mixing the metal salt with the mixed solution, and then slowly adding a 5% sodium hydroxide aqueous solution dropwise to the mixed solution to control the pH of the mixed solution to 9-11.
6. The preparation method according to claim 5, characterized in that, The process parameters for the hydrothermal crystallization reaction are: heating to 150~160℃, heating rate of 10~20℃ / min, and heat treatment for 60~72h.
7. A highly active tunable solid catalyst, characterized in that, It was prepared according to the preparation method of the highly active tunable solid catalyst according to any one of claims 1-6.
8. The highly active tunable solid catalyst according to claim 7, characterized in that, The chemical formula of the catalyst is Cu. 1-x Co x Fe2O4; wherein the loading of transition metals Co and / or Cu is 13~25wt%.
9. The application of a highly active tunable solid catalyst, characterized in that, The highly active tunable solid catalyst prepared by the method according to any one of claims 1-6 is applied to the ortho-alkylation of phenols.
10. The application of the highly active tunable solid catalyst according to claim 9, characterized in that, When the catalyst is applied to the ortho-alkylation of phenols, the reaction conditions are atmospheric pressure, reaction temperature of 80~120℃, and reaction time of 10~12 hours.