Extrusion molding catalyst for ortho-alkylation reaction and preparation method thereof

Abstract

The present invention relates to an extrusion molding catalyst for an ortho-alkylation reaction and a preparation method thereof, and more particularly, to an extrusion molding catalyst for an ortho-alkylation reaction, which can minimize the mass diffusion resistance of the catalyst in an ortho-alkylation reaction of a phenolic compound, and improve the yield of the catalyst. Therefore, the ortho-alkylation reaction product with high selectivity and conversion rate is obtained, and the invention also relates to a method for preparing the ortho-alkylation reaction product by using the catalyst.

Description

Technical Field

[0001] Cross-reference to related applications This application claims priority to Korean Patent Application No. 10-2023-0055405, filed on April 27, 2023, all of which is disclosed herein by reference.

[0002] This invention relates to an extrusion molding catalyst for ortho-alkylation reactions and a method for preparing the same, and more specifically, to an extrusion molding catalyst for ortho-alkylation reactions that minimizes the mass diffusion resistance of the catalyst in ortho-alkylation reactions of phenolic compounds, thereby obtaining ortho-alkylation reaction products with high selectivity and conversion, and a method for preparing the same. Background Technology

[0003] Alkylated hydroxyl aromatic compounds are used for a variety of purposes and are typically prepared from phenol and methanol via a gas-phase reaction. Furthermore, through further alkylation reactions, compounds with various structures can be produced, which are readily applicable to high-performance thermoplastic product lines.

[0004] These additional alkylation reactions are typically carried out in the presence of magnesium-based compounds, and various studies have been conducted to optimize the performance of magnesium-based catalysts.

[0005] In alkylation reactions, magnesium-based catalysts require high activity, long activity lifetime, and high selectivity for the desired reaction products. Most previously used alkylation catalysts produced large quantities of para-alkylation products, leading to various studies aimed at obtaining higher yields of more useful ortho-alkylation products.

[0006] However, conventional techniques, in addition to magnesium-based catalysts, require the use of co-catalyst compounds, alteration of catalyst composition, or modification of reaction conditions. Therefore, it is difficult to obtain the desired high selectivity and high yield of ortho-alkylated products using such conventional techniques.

[0007] Therefore, there is a need to develop an improved catalyst to enhance the catalyst selectivity, catalytic activity, productivity, cost reduction, and overall productivity of ortho-alkylation reactions.

[0008] Meanwhile, for alkylation reactions, powdered catalysts can be used in small quantities at the laboratory level, but in order to mass-produce catalysts and apply them to commercial fixed-bed reactors, the pressure drop during the reaction must be taken into account, and the catalysts must be properly shaped to fit the reactor.

[0009] Common methods for catalyst molding include extrusion molding and tableting. Tableting can produce molded bodies with precise shapes, but the equipment is expensive and the preparation cost is high, significantly reducing economic feasibility. On the other hand, extrusion molding is a commonly used molding method due to its simple equipment and relatively low preparation cost. However, catalyst molding can affect internal / external mass diffusion resistance, leading to a decrease in the activity of the prepared catalyst. Therefore, various studies are needed to minimize the activity reduction. Summary of the Invention

[0010] [Technical Issues] This invention aims to provide an extrusion molding catalyst for ortho-alkylation reactions, which achieves excellent conversion and yield in the production of products from selective ortho-alkylation reactions. Furthermore, this invention also aims to provide an extrusion molding catalyst for ortho-alkylation reactions that achieves uniform catalytic activity both inside and outside the molded catalyst without diminishing activity.

[0011] Furthermore, the present invention also provides a method for preparing the catalyst.

[0012] [Technical Solution] To address the aforementioned problems, this invention provides an extrusion catalyst for ortho-alkylation reactions, comprising magnesium oxide, having macropore diameters of 50 nm to 10000 nm, mesopore diameters of 2 nm to 50 nm, and a BET specific surface area of ​​45 m². 2 / g to 180 m 2 / g.

[0013] Furthermore, the present invention also provides a method for preparing the extrusion molding catalyst for ortho-alkylation reaction.

[0014] Specifically, the present invention provides a method for preparing an extrusion molding catalyst for ortho-alkylation reactions, comprising: The first step is to prepare a material with a bimodal pore structure and a BET specific surface area of ​​100 m². 2 / g to 180 m 2 A mixture of / g magnesium oxide, organic binder resin, and solvent; and The second step is to extrude the mixture into a shape.

[0015] Beneficial effects The extrusion catalyst for ortho-alkylation reaction according to the present invention exhibits high catalytic activity and high selectivity and conversion rate when used to prepare ortho-alkylation reaction products.

[0016] Furthermore, the present invention provides an extrusion-molded catalyst for ortho-alkylation reactions, wherein macropores and mesopores are appropriately formed and have a suitable BET specific surface area, thereby minimizing the mass transfer resistance of the catalyst and ensuring uniform and excellent catalytic activity both inside and outside the molded catalyst without any loss of activity.

[0017] The extrusion catalyst for ortho-alkylation reaction according to the present invention is prepared by using a combination of magnesium oxide with specific physical properties, organic binder resin and solvent, thereby exhibiting high catalytic activity without the need for separate co-catalysts or other additives, and exhibiting very high selectivity and conversion when used to prepare ortho-alkylation reaction products. Attached Figure Description

[0018] Figure 1 To illustrate the relationship between the conversion rate and selectivity of the catalyst type in the molding catalysts used for ortho-alkylation reactions according to the embodiments and comparative examples of the present invention.

[0019] Figure 2 A graph showing the relationship between the conversion rate and selectivity of the type / content of binder resin in the molding catalyst for ortho-alkylation reaction according to an embodiment of the present invention.

[0020] Figure 3 A graph showing the relationship between pore size and pore volume for the types of molded catalysts according to embodiments and comparative examples of the present invention. Detailed Implementation

[0021] Since the present invention can be modified and taken in various forms, specific embodiments will be described in detail below. However, this is not intended to limit the invention to the specific forms disclosed, but should be understood to cover all modifications, equivalents, or substitutions within the spirit and scope of the invention.

[0022] Furthermore, the terminology used in this specification is for describing exemplary embodiments only and is not intended to limit the invention. Unless the context clearly indicates otherwise, singular expressions also include plural expressions. In this specification, terms such as “comprising,” “including,” or “having” are intended to indicate the presence of implemented features, steps, components, or combinations thereof, and should be understood to not exclude the possibility of the presence or addition of one or more other features, steps, components, or combinations thereof.

[0023] Furthermore, in this invention, when a component is described as being formed "on" or "above" another component, it means that the component can be formed directly on the other component, or that additional components can be formed between layers, on an object, or on a substrate.

[0024] Typically, magnesium-based catalysts used in alkylation reactions require high activity, long activity lifetime, and high selectivity for the desired reaction products. Most alkylation catalysts used in the past produced large quantities of para-alkylation products, leading to various studies aimed at obtaining more useful ortho-alkylation products with high selectivity.

[0025] Specifically, in recent years, various techniques have been developed, such as combining magnesium-based catalysts with co-catalyst compounds, modifying catalyst composition, or altering reaction conditions. However, a problem with these techniques is the difficulty in obtaining ortho-alkylation products with the desired high selectivity and high conversion rates.

[0026] To address these issues, the inventors of this invention demonstrated that, for extrusion catalysts containing specific magnesium oxide, when the catalyst satisfies an appropriate pore distribution and BET specific surface area, it can achieve significantly high catalytic activity in alkylation reactions. Accordingly, the inventors discovered that the ortho-alkylation reaction catalyst according to the present invention, as a single catalyst, exhibits excellent catalytic activity without the need for additional co-catalysts or adjustment of reaction conditions, and when used to prepare ortho-alkylation reaction products, it can exhibit significantly high selectivity and conversion, thus completing the present invention.

[0027] Meanwhile, for alkylation reactions, powdered catalysts can be used in small quantities at the laboratory level. However, for mass production and application in industrial fixed-bed reactors, the pressure drop during the reaction must be considered, and the catalyst must be appropriately shaped to fit the reactor. Common methods for catalyst shaping include extrusion molding and tablet molding. Tableting molding can produce precisely shaped bodies, but the equipment is expensive, resulting in high preparation costs, which significantly reduces economic feasibility. On the other hand, extrusion molding is a commonly used method because the equipment is simple and the preparation cost is relatively low. However, during catalyst extrusion molding, the internal and external mass diffusion resistance is affected, leading to a decrease in the activity of the extruded catalyst.

[0028] Therefore, to address these issues, the inventors of this invention identified the main factors affecting the catalytic activity of the extrusion catalyst during preparation. Specifically, as described above, by using magnesium oxide with a specific pore structure, and simultaneously forming appropriate large and medium-sized pores in the final catalyst to obtain a suitable BET specific surface area, the influence on internal / external mass diffusion resistance was minimized, and it was confirmed that the prepared extrusion catalyst could achieve uniform catalytic activity, thus completing this invention.

[0029] I. Extrusion catalysts for ortho-alkylation reactions An extrusion catalyst for ortho-alkylation reactions according to embodiments of the present invention comprises magnesium oxide, having macropores with a diameter of 50 nm to 10000 nm and mesopores with a diameter of 2 nm to 50 nm, and satisfying a 45 nm... 2 / g to 180 m 2 / g BET specific surface area.

[0030] Typically, the catalytic activity of a catalyst depends on the reaction conditions or the acid-base properties of the catalyst. In the alkylation reaction of meta-alkyl-substituted phenolic monomers, if the catalyst is basic, it will adsorb the reactants vertically, which favors ortho-C-alkylation (see formula (a) below). Therefore, the ortho-alkylation catalyst according to the present invention comprises a magnesium oxide (MgO) component.

[0031]

[0032] This catalyst is prepared using magnesium oxide with a bimodal pore structure. Specifically, the magnesium oxide used in the preparation step has a bimodal form with medium-sized pores (mesopores), which facilitates reactant diffusion and allows the reaction to proceed efficiently. Therefore, it exhibits excellent catalytic activity in ortho-alkylation reactions, demonstrating high selectivity, conversion, and yield.

[0033] Extrusion catalysts used for ortho-alkylation reactions include macropores with pore sizes ranging from 50 nm to 10,000 nm and mesopores with pore sizes ranging from 2 nm to 50 nm.

[0034] In this way, by appropriately forming macropores and mesopores, the mass diffusion resistance of the catalyst is minimized, thereby enabling uniform and excellent catalytic activity both inside and outside the formed catalyst without reducing its activity.

[0035] The macropore content of the extruded catalyst for ortho-alkylation reaction can be 1 to 10% by volume relative to the total pore volume of macropores and mesopores, preferably 1 to 9% by volume, 2 to 10% by volume, 2 to 9% by volume, or 2 to 5% by volume. Contents within this range are preferred because they minimize the mass diffusion resistance of the shaped catalyst.

[0036] The mesopore content of the extruded catalyst for ortho-alkylation reaction can be 90 to 99% by volume relative to the total pore volume of macropores and mesopores, preferably 90 to 98% by volume, 91 to 98% by volume, or 95 to 98% by volume. When the content is within this range, the extruded catalyst can exhibit excellent catalytic activity without reduction in activity.

[0037] The methods for measuring the pore size and pore volume distribution of the catalyst will be described in more detail in the Experimental Examples section below.

[0038] The extrusion catalyst used for ortho-alkylation reaction has a 45 m 2 / g to 180 m 2 / g BET specific surface area.

[0039] By exhibiting a specific range of BET specific surface area values ​​with appropriately formed macropores and mesopores, this catalyst can minimize the mass diffusion resistance of the catalyst and achieve uniform and excellent catalytic activity both inside and outside the shaped catalyst without reducing its activity.

[0040] Preferably, the specific surface area of ​​BET can be 45 m². 2 / g to 150 m 2 / g、45 m 2 / g to 130 m 2 / g or 60 m 2 / g to 130 m 2 / g. A specific surface area within this range is preferred because it minimizes the mass diffusion resistance of the shaped catalyst. The method for measuring the BET specific surface area of ​​the catalyst will be described in more detail in the Experimental Examples section below.

[0041] Furthermore, by combining magnesium oxide with specific physical properties with organic binder resins and solvents to prepare catalysts, the pore size distribution and BET specific surface area of ​​the catalysts can be optimized. This will be described in more detail in the preparation method section.

[0042] The particle size of the extruded catalyst used for ortho-alkylation reactions can be from 0.5 mm to 6.0 mm, within which it exhibits uniform and excellent catalytic activity. More preferably, the catalyst particle size can be from 1.0 mm to 3.0 mm or from 1.2 mm to 2.0 mm. If the catalyst particle size deviates from the above range and becomes too small, a large pressure drop may occur during the alkylation reaction, causing problems. Conversely, if the catalyst particle size deviates from the above range and becomes too large, there is a concern that the catalytic activity may decrease.

[0043] The size of the catalyst can be controlled based on the diameter of the extrusion die used in the final extrusion step of the preparation process.

[0044] Typically, the shape of an extruded catalyst is a cylinder achieved by an extrusion die, and the extruded catalyst according to the present invention can have a 1:1 (±0.1) ratio of the diameter of the circular cross-section of the cylinder to the length of the cylinder.

[0045] Therefore, the dimensions of the extruded catalyst can refer to the diameter of the circular cross-section of the cylinder and / or the length of the cylinder, preferably both the cross-sectional diameter and the length of the cylinder falling within the aforementioned range.

[0046] The specific methods for measuring catalyst size will be described in more detail in the Experimental Examples section below.

[0047] II. A method for preparing an extrusion catalyst for ortho-alkylation reactions. According to another embodiment of the present invention, as a method for preparing the above-described extrusion molding catalyst, a method for preparing an extrusion molding catalyst for ortho-alkylation reaction is provided, comprising the following steps.

[0048] Specifically, it includes: First, preparing a material with a bimodal pore structure and a BET specific surface area of ​​100 m². 2 / g to 180m 2 A mixture of / g magnesium oxide, organic binder resin and solvent; the second step is to extrude the mixture.

[0049] The following is a detailed explanation of each step.

[0050] Step 1: Preparing the mixture First, by using a bimodal pore structure with a BET specific surface area of ​​100 m² 2 / g to 180 m 2 A mixture is prepared by mixing / g of magnesium oxide, organic binder resin and solvent.

[0051] The same descriptions of extrusion catalysts used in ortho-alkylation reactions can be applied to magnesium oxide.

[0052] Preferably, magnesium oxide has a bimodal pore structure, specifically a bimodal form within the medium-sized pore (medium-sized pore: mesopore) range, which facilitates reactant diffusion and allows the reaction to proceed efficiently. Therefore, it exhibits excellent catalytic activity in ortho-alkylation reactions, demonstrating high selectivity, conversion, and yield.

[0053] Generally, the larger the BET specific surface area, the more active sites the catalyst has. However, in the case of a single-peak morphology, even with an increase in the BET specific surface area, the diffusion of reactants is not smooth, making it difficult to achieve the desired reaction extent.

[0054] Preferably, in the bimodal pore structure, the diameter of the first pore can be from 2 nm to 10 nm, and the diameter of the second pore can be from 10 nm to 50 nm. More preferably, the diameter of the first pore can be from 4 nm to 8 nm, and the diameter of the second pore can be from 20 nm to 45 nm or from 35 nm to 45 nm. With a bimodal pore structure having diameters within this range, desired superior catalytic activity, improved selectivity, conversion, and yield can be exhibited.

[0055] The BET specific surface area of ​​magnesium oxide is 100 m². 2 / g to 180 m 2 Due to its relatively large specific surface area, it possesses numerous reaction sites, resulting in excellent catalytic activity. Furthermore, as mentioned above, its bimodal porous structure facilitates reactant diffusion, enabling efficient reaction. Therefore, it exhibits excellent catalytic activity in ortho-alkylation reactions, demonstrating improved selectivity, conversion, and yield. If the BET specific surface area is less than 100 m² / g... 2 The number of reaction sites decreases significantly with a surface area of ​​ / g, resulting in low reactant conversion and difficulty in achieving the desired activity. Furthermore, if the specific surface area of ​​BET exceeds 180m², the reaction will be significantly reduced. 2 / g, the number of reaction sites increases, but mainly the first pore is formed, which hinders the diffusion of reactants and products, making it difficult to achieve high activity.

[0056] Preferably, the BET specific surface area of ​​magnesium oxide can be 130 m². 2 / g to 180 m 2 / g, more preferably, 130 m 2 / g to 150 m 2 / g, and is preferred within this range, because excellent catalytic activity can be obtained without the aforementioned problems.

[0057] Organic binder resins are components that facilitate catalyst preparation by uniformly binding magnesium oxide during the preparation of molded catalysts, particularly in the preparation of extruded catalysts. They play a crucial role in achieving uniform catalytic activity by forming suitable pores within the catalyst through calcination. Using magnesium oxide alone, which possesses the aforementioned specific physical properties, may reduce the ease of catalyst preparation and make it difficult to form the desired pores; however, combined use is preferred because it can achieve superior catalytic activity more uniformly.

[0058] Specific examples of organic adhesive resins include methylcellulose, carboxymethylcellulose, ethylene glycol, polyethylene glycol, polyphenylene ether, glycerin, and propylene glycol. These resins can be used alone or in combination of two or more. More preferably, methylcellulose, carboxymethylcellulose, and polyethylene glycol (PEG20000 or PEG400) can be used.

[0059] Based on 100 parts by weight of magnesium oxide, the content of the organic adhesive resin can be from 0.1 to 20 parts by weight, preferably from 0.1 to 15 parts by weight, 0.1 to 10 parts by weight, or 1 to 5 parts by weight. Use within this range is beneficial for achieving the aforementioned effects.

[0060] Solvents are used to allow the mixture to be kneaded evenly and to aid in the extrusion process when preparing extruded parts.

[0061] Specific examples of solvents include water and alcohols, which can be used alone or in combination of two or more. Water is preferred. The water can be high-purity water, such as distilled water, ion-exchanged water, or deionized water (DIW). If the water contains impurities, these impurities may adhere to the catalyst and reduce its activity; therefore, deionized water is preferred. In the case of alcohols, primary alcohols with three or more carbon atoms are preferred.

[0062] Based on 100 parts by weight of magnesium oxide, the solvent content can be 50 to 200 parts by weight, preferably 80 to 150 parts by weight or 100 to 120 parts by weight. The mixture prepared in this proportion is preferably in paste form. In this case, the extrusion molding process is easier to perform and is therefore preferred.

[0063] Furthermore, according to one embodiment of the invention, optional additional additives may also be used in the mixture; for example, a lubricant may be used to prevent unevenness or breakage of the final catalyst during preparation. Specific examples of such lubricants include, but are not limited to, magnesium stearate, aluminum stearate, and graphite.

[0064] Furthermore, other additives used in the art may be used without particular limitation, provided that the desired physical properties are not impaired.

[0065] Step 2: Extrusion Molding Next, it includes a second step of extruding the mixture into a shape.

[0066] Tableting is a commonly used catalyst molding method that can produce precisely shaped molded bodies, but the equipment is expensive and the preparation cost is high, greatly reducing its economic feasibility. On the other hand, extrusion molding is a commonly used molding method because its equipment is simple and the preparation cost is relatively low. However, catalyst molding affects the internal / external mass diffusion resistance, resulting in a decrease in the activity of the prepared molded catalyst. As described above, in the case of the present invention, by using a combination of magnesium oxide, organic binder resin and solvent with specific physical properties, an extruded catalyst with high activity and uniform internal and external properties can be manufactured, thereby avoiding the above-mentioned problems.

[0067] Extrusion molding processes can typically utilize screw extruders and piston extruders, but a single-piston extruder is preferred. In this case, extrusion catalysts with low moisture content and high compression ratios can be produced under high pressure. In this scenario, the extrusion process can be performed using a die of a specific diameter, but is not limited to this.

[0068] The average diameter of the extrusion die used can be appropriately adjusted according to the desired diameter range of the final shaped catalyst.

[0069] Additional steps: drying and calcination In one embodiment of the present invention, the process after extrusion molding may further include drying and calcination steps.

[0070] The process conditions for the above drying and calcination steps can be those commonly used in the field, without any particular limitations.

[0071] Specifically, there are no particular restrictions on the temperature at which the drying step is performed; for example, the drying step can be performed at 80°C to 120°C, preferably at 90°C to 110°C.

[0072] There is no particular limitation on the time for the drying step, but it can be carried out for, for example, from 1 hour to 13 hours, preferably from 3 hours to 8 hours, or from 4 hours to 6 hours.

[0073] There are no particular restrictions on the temperature at which the calcination step is carried out, but it can be carried out, for example, at 300°C to 600°C, preferably at 400°C to 550°C.

[0074] The duration of the calcination step is not particularly limited, but it must be carried out for a sufficient time to remove the organic binder resin and solvent from the mixture, thereby forming the desired pores in the catalyst. Preferably, it is carried out for 1 to 9 hours, more preferably 3 to 6 hours.

[0075] The catalyst prepared according to the above method for preparing an extrusion-molded catalyst for ortho-alkylation reaction can achieve uniform and excellent catalytic activity inside and outside the molten catalyst by using a combination of magnesium oxide, organic binder resin and solvent with specific physical properties, without any loss of activity.

[0076] III. Ortho-alkylation reaction composition According to one embodiment of the present invention, the ortho-alkylation reaction composition comprises the above-described extrusion molding catalyst for ortho-alkylation reaction and a monomer composition comprising a meta-alkyl-substituted phenolic monomer.

[0077] The extrusion catalyst for ortho-alkylation reactions comprises magnesium oxide and has macropores with a pore size of 50 nm to 10,000 nm and mesopores with a pore size of 2 nm to 50 nm, and satisfies a BET specific surface area of ​​45 m². 2 / g to 180 m 2 / g, all of the above applies equally to this.

[0078] Specifically, by appropriately forming the aforementioned macropores and mesopores, the mass diffusion resistance of the catalyst is minimized, thereby enabling uniform and excellent catalytic activity both inside and outside the formed catalyst without reducing its activity.

[0079] Furthermore, the magnesium oxide contained in this catalyst has a bimodal pore structure, specifically a bimodal form of medium-sized pores (mesopores), which facilitates the diffusion of reactants and enables the reaction to proceed efficiently. In addition, by simultaneously satisfying the aforementioned specific range of BET specific surface area, this catalyst exhibits excellent catalytic activity, as well as high selectivity and conversion in ortho-alkylation reactions.

[0080] In this monomer composition, the meta-alkyl-substituted phenolic monomer may be m-cresol.

[0081] In addition to the meta-alkyl-substituted phenol monomer, the monomer composition further comprises an alkanol and distilled water (DIWater). The alkyl group can be introduced through reaction with the alkanol, and the decomposition reaction of the alkanol can be suppressed by the simultaneous use of distilled water, which is therefore preferred. The alkanol is preferably methanol.

[0082] The monomer composition preferably consists of a phenolic monomer: alkanol: distilled water in a weight ratio of 1:3-10:1-5, more preferably 1:4-6:1-3. In this case, if the alkanol content is below the above range, the conversion rate will decrease due to the small amount of alkylating agent used; if the distilled water content is below the above range, the effect of inhibiting the decomposition reaction of the alkanol will be reduced. If the alkanol or distilled water content is above the above range, it will compete with the phenolic monomer for adsorption at the catalyst active sites, which may lead to a decrease in reactivity.

[0083] It is preferred when it is present in the above-mentioned content range, because the ortho-alkylation reaction product can be prepared with the desired selectivity and conversion.

[0084] IV. Preparation method of ortho-alkylation reaction product According to an embodiment of the present invention, a method for preparing an ortho-alkylation reaction product includes: alkylating a monomer composition comprising a meta-alkyl-substituted phenolic monomer in the presence of the aforementioned extrusion molding catalyst for the ortho-alkylation reaction. Specifically, this method for preparing the ortho-alkylation reaction product can be carried out using an ortho-alkylation reaction composition comprising the aforementioned extrusion molding catalyst for the ortho-alkylation reaction. All of the foregoing applies equivalencely to the catalyst and the reaction composition.

[0085] The extrusion catalyst for the ortho-alkylation reaction comprises magnesium oxide and has macropores with a pore size of 50 nm to 10,000 nm and mesopores with a pore size of 2 nm to 50 nm, and satisfies a BET specific surface area of ​​45 m². 2 / g to 180 m 2 / g. All of the above applies equally to this.

[0086] Specifically, by including the above-mentioned extrusion-molded catalyst, uniform and excellent catalytic activity can be achieved both inside and outside the molded catalyst without reducing catalytic activity.

[0087] In the method for preparing the ortho-alkylation reaction product, all of the above-mentioned provisions are equally applicable to the monomer composition. Specifically, the meta-alkyl-substituted phenolic monomer in the monomer composition can be m-cresol. By using a reaction composition containing the above-described extrusion catalyst, the method for preparing the ortho-alkylation reaction product can exhibit high selectivity and conversion for the desired ortho-alkylation reaction product.

[0088] The ortho-alkylation product can be, for example, one or more selected from 2,5-dimethylphenol, 2,3-dimethylphenol, 2,3,6-trimethylphenol, 3-methylanisole, 3,4-dimethylphenol, and tetramethylphenol. For example, it can be prepared by selectively substituting the ortho-alkyl group in m-cresol through a multi-step reaction as shown below.

[0089]

[0090] The alkylation reaction is preferably carried out at 350°C to 550°C, more preferably at 350°C to 550°C. At this temperature, if the temperature is below 350°C, the alkylation reaction may not be sufficiently activated, while if the temperature exceeds 550°C, excessive reaction will produce a large amount of byproducts.

[0091] The alkylation reaction can be carried out under inert conditions, for example, in the presence of an inert carrier gas. Nitrogen, helium, neon, argon, etc., can be used as the inert carrier gas, with nitrogen being preferred.

[0092] There is no particular limitation on the flow rate of nitrogen, but it is preferably 5 to 70 cc / min, 10 to 50 cc / min or 15 to 40 cc / min. When the reaction is carried out under these conditions, the ortho-alkylated product can be generated with the desired selectivity and conversion.

[0093] Simultaneously, in the alkylation reaction, before injecting the monomer composition, a step can be performed to heat the inside of the reactor and maintain it at the activation temperature to activate the catalyst. This temperature range can be the same as the reaction temperature. There is no particular limitation on the catalyst activation time, but it can be approximately 30 minutes to 1 hour.

[0094] Alkylation reactions are preferably carried out using a continuous flow gas-phase reactor, in which case the monomer composition can be injected into the reactor at an LHSV (liquid hourly space velocity) of 0.5 hr⁻¹ to 2.0 hr⁻¹. If this space velocity range is exceeded, the reactants may not be sufficiently activated at the catalyst's active sites, making it difficult to obtain the product. Furthermore, the catalyst's activity or selectivity may decrease, reducing the amount of product.

[0095] The reaction is preferably carried out under the above conditions because the ortho-alkylation reaction product can be prepared with the desired selectivity and conversion.

[0096] The operation and effects of the present invention will be described in more detail below through specific embodiments. However, these embodiments are merely examples of the present invention and should not be construed as limiting the scope of the present invention or its patent rights.

[0097] [Example 1 and Comparative Example 1] Example 1-1. Preparation of extruded catalysts (Preparation of extruded catalysts) 50 g of magnesium oxide (MgO powder, grain size 9 nm, BET surface area 144.4 m²) was used. 2 / g, total pore volume 0.72 cm³ 3 In a mixing bowl, combine 1 g of organic binder resin (methylcellulose) with 60 g of water (pore size 6.40 nm) and mix thoroughly to form a paste. After mixing, extrude the paste through a 2 mm diameter die using a single-piston extruder. Spread the extruded noodle-like material evenly onto a tray.

[0098] Next, after drying in a convection furnace at 100°C for 4 hours, the dried extrusion catalyst was cut at 2 mm intervals and calcined in a muffle furnace at 450°C for 6 hours to prepare a magnesium-based extrusion catalyst (A-1).

[0099] Comparative Example 1-1. Preparation of Tablet Catalysts First, magnesium oxide (MgO powder, grain size 9 nm, BET surface area 144.4 m²) is pressed using a flatbed tablet press and an aluminum disc. 2 / g, total pore volume 0.72 cm³ 3 The tablets (6-40 nm pore size) were compressed into discs and then pulverized to prepare granules with an appropriate particle size to impart flowability. 10 wt% of an organic binder resin (PPO, polyphenylene ether) and 1 wt% of a lubricant (magnesium stearate) were mixed with the prepared granules, and tablets with a diameter of 2.4 mm were prepared using a single-rotation tableting catalyst molding machine.

[0100] Next, the sheet-shaped catalyst was dried in a convection furnace at 100°C for 4 hours and then calcined in a muffle furnace at 450°C for 1 hour to obtain a magnesium-based sheet-shaped catalyst (B-1).

[0101] Examples 1-2 to 1-8 Except for changes to the composition and content of the adhesive resin and solvent used, as shown in Table 1 below, the operation was carried out in the same manner as in Examples 1-1.

[0102]

Table 1

[0103] [Experimental Example 1: Analysis of Catalysts for Ortho-alkylation Reaction] (1) BET specific surface area analysis The catalysts of Example 1 and Comparative Example 1 were subjected to nitrogen adsorption-desorption analysis experiments. The BET specific surface area was measured by the isothermal adsorption curves and the amount of adsorbed nitrogen at standard temperature and pressure according to the BET (Brunauer Emmett Teller) calculation formula. The results are shown in Table 2.

[0104] The average diameter of a catalyst in extrusion form refers to the diameter of the circular cross-section of a cylindrical catalyst prepared by a die mounted on a single-piston extruder, while the average diameter of a catalyst in tablet form refers to the diameter of the circular cross-section of a cylindrical catalyst prepared by a punch mounted on a rotary tablet press.

[0105] Table 2

[0106] (2) Hg porosity analysis The pore structure of the macroporous and mesoporous regions of the catalysts in Example 1 and Comparative Example 1 was confirmed by mercury intrusion porosimetry. The results are shown in Table 3 and... Figure 3 As shown in the image.

[0107] Table 3

[0108] * Indicates the proportion of macro- and meso-holes in the total pore volume. From Tables 2 and 3 and Figure 3 It can be seen that, in order to minimize the loss of activity due to internal and external mass diffusion resistance, it is preferable to prepare the extruded catalyst in the form of an extrudate using appropriate organic binder resins and solvents as defined herein. Therefore, it was confirmed that appropriate pore sizes were formed in the mesoporous to microporous range, and the BET specific surface area was within an appropriate range.

[0109] By achieving the appropriate pore distribution and BET surface area, the mass diffusion resistance during the alkylation reaction can be minimized, thereby obtaining high conversion and selectivity. This will be described in more detail in Experimental Example 2.

[0110] [Example 2 and Comparative Example 2] Example 2-1: Preparation of the alkylation product of m-cresol The alkylation reaction of m-cresol was carried out in a continuous flow gas-phase reactor. First, 1 g of the shaped catalyst prepared in Example 1-1, which has the physical properties shown in Table 1, was loaded into a stainless steel tubular reactor with a diameter of 1 / 2 inch and a length of 50 cm, and then installed into the main furnace.

[0111] Subsequently, N2 carrier gas (37.5 cc / min) was introduced using a mass flow controller (MFC) to raise the reactor temperature to 450°C and maintain this temperature for 1 hour to activate the catalyst. Then, the monomer composition (12.5 mg / min, m-cresol:methanol:distilled water = 1:5:1, LHSV 0.75 / h) was introduced into the preheater (250°C), vaporized, and then injected. The reaction composition containing the catalyst and monomer composition was injected into the reactor, and then alkylation was carried out (450°C, maintained at atmospheric pressure) for 5 hours to obtain the reaction product.

[0112] The product was collected in liquid form during the reaction (using IPA (isopropanol) as a solvent) for analysis.

[0113] Examples 2-2 to 2-8, Comparative Example 2-1 Except that the catalyst was changed from that in Example 1-1 to that in Examples 1-2 to 1-8 and Comparative Examples 1-1 in Table 1, the alkylation reaction was carried out in the same manner as in Example 2-1 to obtain the reaction product.

[0114] [Experimental Example 2: Analysis of Products from Ortho-alkylation Reaction] (2-1) Analyze the reaction products according to the catalyst type The liquids containing the reaction products prepared in Example 2 and Comparative Example 2 were analyzed by gas chromatography (GC) using a gas chromatograph equipped with a flame ionization detector (FID). Based on the GC data, the conversion of m-cresol and the selectivity of the target products (2,3,6-TMP, 2,5-DMP, 2,3-DMP, tetramethylphenol) were calculated using Formulas 1 and 2 below. The results are shown in Table 4. Figure 1 (Catalyst type (size / shape)) and Figure 2 (The type / content of binder resin used in catalyst preparation is shown in the table.)

[0115] The target products are defined as the final target product 2,3,6-TMP and intermediate substances 2,5-DMP and 2,3-DMP, which are obtained through an addition reaction.

[0116] [Formula 1]

[0117] [Formula 2]

[0118] Table 4

[0119] The experimental data in Table 4 confirm that when using the extrusion molding catalyst according to the present invention, high catalytic activity is exhibited even when using a single catalyst, and when used to prepare ortho-alkylation reaction products, very high selectivity and conversion rates are demonstrated.

[0120] In Comparative Example 2-1, it was difficult to achieve the desired level of catalytic activity by using a sheet-shaped catalyst, thus confirming that the conversion rate and other parameters were lower compared to the examples.

[0121] (2-2) Analyze the products according to the reaction conditions Example 3: Changing the reaction temperature Except that the methylation reaction temperature was started at 400°C and increased by 10°C every 3 hours until it reached 450°C, the alkylation reaction was carried out in the same manner as in Example 2-1. Furthermore, the conversion rate of m-cresol and the selectivity of the target products (2,3,6-TMP, 2,5-DMP, 2,3-DMP) were calculated according to the method of Experimental Example 2 above, and the results are shown in Table 5 below.

[0122] Example 4: Changing the carrier gas flow rate Except that the carrier gas flow rate was 18.7 cc / min, the alkylation reaction was carried out in the same manner as in Example 2-1, and the conversion of m-cresol and the selectivity of the target products (2,3,6-TMP, 2,5-DMP, 2,3-DMP) were calculated according to the method of Experimental Example 2 above. The results are shown in Table 5 below.

[0123] Example 5: Changing the methanol injection volume Except for the injection of liquid mixtures containing reactants in the form of m-cresol:methanol:distilled water = 1:4:1 (11.1 mg / min, LHSV 0.666 / h) and m-cresol:methanol:distilled water = 1:3:1 (9.7 mg / min, LHSV 0.582 / h), the alkylation reaction was carried out in the same manner as in Example 1, and the conversion of m-cresol and the selectivity of the target products (2,3,6-TMP, 2,5-DMP, 2,3-DMP) were calculated according to the method of Experimental Example 2 above. The results are shown in Table 5 below.

[0124] Table 5

[0125] The experimental data in Table 5 confirm that, in the case of Example 3, the methylation reaction temperature started at 400°C and increased by 10°C every 3 hours until it reached 450°C. This confirms that the catalyst performance improves with increasing reaction temperature.

[0126] In Example 4, the flow rate of the nitrogen feed was changed, thereby confirming its effect on the catalyst-reactant contact time (GHSV, gas hourly space velocity).

[0127] In Example 5, the ratio of injected raw materials was changed, thus confirming that the ratio of reactant m-cresol to alkylating agent methanol had an effect.

Claims

1.An extrusion-molded catalyst for an ortho-alkylation reaction, comprising magnesium oxide; including a large pore having a diameter of 50 nm to 10,000 nm and a medium pore having a diameter of 2 nm to 50 nm; and having a BET specific surface area of 45 m 2 / g to 180 m 2 / g. 2.The extrusion-molded catalyst for an ortho-alkylation reaction according to claim 1, wherein with respect to the total pore volume of the large pore and the medium pore, the large pore content is 1 to 10 vol%, and the medium pore content is 90 to 99 vol%. 3.The extrusion-molded catalyst for an ortho-alkylation reaction according to claim 1, wherein the size of the extrusion-molded catalyst is 0.5 mm to 6.0 mm. 4.A method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 1, comprising: In a first step, a mixture of magnesium oxide having a bimodal pore structure and a BET specific surface area of 100 m 2 / g to 180 m 2 / g, an organic binder resin and a solvent is prepared; and a second step of extrusion-molding the mixture. 5.The method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 4, wherein the bimodal pore structure of the magnesium oxide includes a first pore having a diameter of 2 nm to 10 nm and a second pore having a diameter of 10 nm to 50 nm. 6.The method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 4, based on 100 parts by weight of the magnesium oxide, the content of the organic binder resin is 0.1 to 20 parts by weight, and the content of the solvent is 50 to 200 parts by weight. 7.The method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 4, wherein the organic binder resin includes one or more selected from the group consisting of methyl cellulose, carboxymethyl cellulose, ethylene glycol, polyethylene glycol, polyphenylene ether, glycerol, and propylene glycol. 8.The method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 4, wherein the solvent is an alcohol, water, or a mixture thereof. 9.The method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 4, wherein, the solvent is water. 10.The method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 4, wherein, the extrusion-molding of the second step is performed using a single-piston extrusion-molding machine. 11.The method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 4, the extrusion-molding of the second step is further followed by a drying and calcination step. 12.The method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 11, wherein, the drying is performed at 80°C to 120°C. 13.The method for preparing the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 11, wherein the calcination is performed at 300°C to 600°C. 14.An ortho-alkylation reaction composition, comprising, the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 1 and a monomer composition comprising a meta-alkyl-substituted phenolic monomer. 15.A method for preparing an ortho-alkylation reaction product, comprising performing an alkylating reaction on a monomer composition comprising a meta-alkyl-substituted phenolic monomer in the presence of the extrusion-molded catalyst for an ortho-alkylation reaction according to claim 1.

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