Vanadium-titanium catalyst, preparation method and application thereof, and method for synthesizing naphthoquinone

Abstract

The invention particularly relates to a vanadium-titanium catalyst, a preparation method and application thereof and a method for synthesizing naphthoquinone, the catalyst comprises a carrier and an active phase, the active phase comprises vanadium and titanium, and in the catalyst, the size of the active phase is 50-150 microns; the mass ratio of the active phase to the carrier is 0.03 to 0.30. The vanadium-titanium catalyst has high reaction activity, can effectively improve the reactant conversion rate and the product selectivity when being used for oxidation reaction, is applied to a reaction for synthesizing naphthoquinone, is green and environment-friendly in synthesis method, effectively improves the naphthoquinone product yield, and has good industrial application prospects.

Description

Technical Field

[0001] This invention relates to a vanadium-titanium catalyst, its preparation method and application, and a method for synthesizing naphthoquinone. Background Technology

[0002] Naphthoquinone and its derivatives are important fine chemicals, widely used in the synthesis of pharmaceuticals, dyes, fragrances, pesticides, and plasticizers. For example, 1,4-naphthoquinone is an intermediate in the synthesis of anthraquinones and 1-aminoanthraquinones, and also a raw material for the synthesis of 2,3-dihydro-1,4-naphthoquinone and naphthofuran series dyes; alkyl-substituted derivatives of 1,4-naphthoquinone are vitamin K drugs, among which 2-methyl-1,4-naphthoquinone has good hemostatic activity; many derivatives of hydroxy-1,4-naphthoquinone have good bactericidal, medical, and biological properties. Therefore, the direct preparation of naphthoquinone and its derivatives using naphthalene and its derivatives has promising applications.

[0003] There are two common preparation processes for naphthoquinone and its derivatives: 1. Sulfonation and hydrolysis to obtain phenols, followed by catalytic oxidation to obtain naphthoquinone and its derivatives; 2. Indirect electrolytic oxidation using high-valence heavy metal salts or oxidation using non-metallic oxides such as nitric acid and hydrogen peroxide. Both of these processes suffer from problems such as complex procedures, high production costs, small scale, and significant pollution. Direct oxidation of naphthalene and its derivatives with molecular oxygen to prepare naphthoquinone and its derivatives is a green and environmentally friendly process route; however, this process still suffers from problems such as low product yield.

[0004] Therefore, it is necessary to develop a catalyst suitable for the synthesis of naphthoquinone to effectively improve the yield of the synthesized naphthoquinone product. Summary of the Invention

[0005] To address the shortcomings of existing technologies, one of the technical problems this invention aims to solve is to provide a novel vanadium-titanium catalyst. This novel vanadium-titanium catalyst has high reactivity and can effectively improve reactant conversion and product selectivity in oxidation reactions. It is particularly suitable for applications in the oxidation of aromatic hydrocarbons, and especially suitable for applications in the synthesis of naphthoquinone.

[0006] To achieve the above objectives, the first aspect of the present invention provides a vanadium-titanium catalyst comprising a support and an active phase, wherein the active phase comprises vanadium and titanium, and the size of the active phase is 50-150 micrometers; the mass ratio of the active phase to the support is 0.03-0.30.

[0007] A second aspect of the present invention provides a method for preparing the vanadium-titanium catalyst of the present invention, the method comprising:

[0008] (1) Forming an active component source slurry, wherein the active component source slurry contains a polymer compound, wherein the polymer compound is selected from nonionic polymer compounds and / or anionic polymer compounds;

[0009] (2) The active component source slurry is brought into contact with the carrier for loading, and the resulting solid is calcined.

[0010] A third aspect of the present invention provides the application of the catalyst described herein in the oxidation of aromatic hydrocarbons, preferably in the oxidation of polycyclic aromatic hydrocarbons.

[0011] A fourth aspect of the present invention provides a method for synthesizing naphthoquinone, the method comprising: reacting raw material naphthalene and / or alkylnaphthalene with an oxidant in the presence of the catalyst described in the present invention.

[0012] The vanadium-titanium catalyst described in this invention has high reactivity and can effectively improve reactant conversion and product selectivity when applied to oxidation reactions. When this vanadium-titanium catalyst is applied to the synthesis of naphthoquinone, the synthesis method is green and environmentally friendly, and the yield of naphthoquinone product is effectively improved, showing good prospects for industrial application. Detailed Implementation

[0013] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0014] The specific embodiments of the present invention will be described in detail below. However, it should be noted that the scope of protection of the present invention is not limited by these specific embodiments, but is determined by the claims.

[0015] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0016] When this specification uses the prefixes "known to those skilled in the art," "prior art," or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those conventionally used in the art at the time the invention was proposed, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0017] It should be noted that the two or more aspects (or embodiments) disclosed in the context of this specification can be arbitrarily combined with each other, and the resulting technical solutions (such as methods or systems) are part of the original disclosure of this specification and also fall within the protection scope of this invention.

[0018] Unless otherwise specified, all percentages, parts, ratios, etc. mentioned in this specification are based on weight, unless being based on weight would not be in accordance with the common understanding of those skilled in the art.

[0019] This invention provides a vanadium-titanium catalyst comprising a support and an active phase. The active phase comprises vanadium and titanium. The size of the active phase is 50-150 micrometers, preferably 60-100 micrometers. In existing vanadium-titanium catalysts, the size of the active phase is generally greater than 150 micrometers. The mass ratio of the active phase to the support is 0.03-0.30, preferably 0.1-0.2. In this embodiment, a mass ratio of 0.15 is used as an example to illustrate the advantages of this invention, but this does not limit the scope of the invention. The size of the active phase formed by the active components and the mass ratio of the active components to the support have a balance and limiting relationship. The former affects the mass transfer between reactants and products and the transfer of heat of reaction, while the latter affects the reaction activity; therefore, the compatibility of the two is crucial. The vanadium-titanium catalyst of this invention has high reactivity. When applied to oxidation reactions, it can effectively improve the conversion rate of reactants and the selectivity of products. Applying this vanadium-titanium catalyst to the synthesis of naphthoquinone results in a green and environmentally friendly synthesis method, effectively improving the yield of naphthoquinone products, and showing good industrial application prospects.

[0020] In this invention, the active phase refers to the active phase formed by the oxide of the active component.

[0021] In this invention, the active phase scale is measured using a scanning electron microscope.

[0022] In this invention, the mass of the active phase is the mass of the oxide after calcination of the active element.

[0023] In this invention, the mass ratio of the active phase to the support is calculated based on the amount of material fed.

[0024] In this invention, there are no special requirements for the type of catalyst support. Commonly used supports can be used in this invention. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the support is selected from at least one of α-alumina, ceramic rings and silicon carbide. In the embodiments of the invention, α-alumina is used as an example to illustrate the advantages of the invention, but it does not limit the scope of the invention.

[0025] In this invention, the molar ratio of titanium to vanadium can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the molar ratio of titanium to vanadium is 1-50.

[0026] In this invention, other active component elements may be introduced as needed. According to a preferred embodiment of this invention, the active component elements further include non-metallic element M and / or metallic element N.

[0027] In this invention, the range of non-metallic element M is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the non-metallic element M is selected from at least one of the non-metallic elements in Group IIIA, Group VA, and Group VIA. Preferably, the non-metallic element M is selected from at least one of B, N, P, S, and Se, and more preferably from at least one of B, N, and P.

[0028] In this invention, the range of metal element N is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the metal element N is selected from at least one metal element among Group IA, Group IIIA, Group VA, Group IB, Group IIIB, Group VB, Group VIB, and Group VIII. Preferably, the metal element N is selected from at least one element among Li, Na, K, Cs, In, Sb, Bi, Ag, Au, Ce, Nd, Nb, Cr, Mo, W, Fe, Co, and Ir, and more preferably from at least one element among Ce, Mo, and W.

[0029] In this invention, the molar ratio of nonmetallic element M to vanadium can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the molar ratio of nonmetallic element M to vanadium is 0.001-0.1.

[0030] In this invention, the molar ratio of metal element N to vanadium can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the molar ratio of metal element N to vanadium is 0.001-0.05.

[0031] In this invention, the composition of the active component can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the composition of the active component is V-Ti. a -M b -N c -O xThe value of a ranges from 1 to 50, the value of b ranges from 0.001 to 0.1, the value of c ranges from 0.001 to 0.05, and x is the total number of oxygen atoms required to satisfy the oxidation states of each element in the catalyst.

[0032] Catalysts possessing the aforementioned characteristics of this invention can achieve the objectives of this invention, and there are no special requirements for their preparation methods. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, this invention provides a method for preparing the vanadium-titanium catalyst of this invention, the method comprising:

[0033] (1) Forming an active component source slurry, wherein the active component source slurry contains a polymer compound, wherein the polymer compound is selected from nonionic polymer compounds and / or anionic polymer compounds;

[0034] (2) The active component source slurry is brought into contact with the carrier for loading, and the resulting solid is calcined.

[0035] In this invention, the range of nonionic polymeric compounds that can be selected is relatively wide. The following examples illustrate this, but do not limit the scope of the invention. According to a preferred embodiment of the invention, the nonionic polymeric compound is selected from polyenol polymers and / or polyether polymers; preferably, at least one of poly(C2-C6) enols, C2-C18 alkyl polyoxyethylene (C2-C4) alkenyl ethers, and bis(C2-C18) alkyl polyethers; more preferably, at least one of poly(C2-C3) enols, C9-C12 alkyl polyoxyethylene (C2-C3) alkenyl ethers, and bis(C9-C12) alkyl polyethers. In the embodiments of this invention, dodecyl polyoxyethylene ether is used as an example to illustrate the advantages of the invention, but this does not limit the scope of the invention. The vanadium-titanium catalyst of this invention using the aforementioned nonionic polymeric compounds exhibits high reactivity, effectively improving reactant conversion and product selectivity, and is particularly suitable for use in the synthesis of naphthoquinone.

[0036] In this invention, the range of types of anionic polymer compounds is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the anionic polymer compound is selected from carboxylic acid polymers and / or sulfonic acid polymers; preferably, at least one of poly(C3-C6) olefinic acid, C3-C6 olefinic acid copolymer, polystyrene sulfonic acid, benzenesulfonic acid formaldehyde condensate, and sodium lignosulfonate; more preferably, at least one of poly(C3-C5) olefinic acid, acrylic acid maleic anhydride copolymer, polystyrene sulfonic acid, and sodium lignosulfonate.

[0037] According to a preferred embodiment of the present invention, the anionic polymeric compound is selected from poly(C3-C6) olefinic acid and polystyrene sulfonic acid, each with a content of not less than 20 wt%, preferably 30-70 wt%. The vanadium-titanium catalyst prepared using the aforementioned anionic polymeric compound has high reactivity and can effectively improve reactant conversion and product selectivity, making it particularly suitable for use in the synthesis of naphthoquinone.

[0038] In this invention, the degree of polymerization of the polymer compound can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the degree of polymerization of the polymer compound is 10-2000.

[0039] In this invention, the amount of the polymer compound can be selected within a wide range. The following is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the mass ratio of the polymer compound to the vanadium source in the active component source slurry is 0.1-5:1, preferably 1-3:1. In the embodiments of this invention, the mass ratios of the polymer compound to the vanadium source in the active component source slurry are 0.1:1, 2:1, 3:1, and 4.8:1, which are examples illustrating the advantages of the invention, but do not limit the scope of the invention. The vanadium-titanium catalyst prepared using the aforementioned mass ratio of the polymer compound to the vanadium source in the active component source slurry exhibits high reactivity. When applied to oxidation reactions, it can effectively improve reactant conversion and product selectivity, and is particularly suitable for use in the synthesis of naphthoquinone.

[0040] In this invention, the range of vanadium sources that can be selected in the active component source slurry is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the vanadium source is selected from vanadium salts and / or vanadium oxides, more preferably at least one of ammonium metavanadate, vanadium oxalate, and vanadium pentoxide.

[0041] In this invention, the range of titanium sources that can be selected in the active component source slurry is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the titanium source is selected from titanium salts and / or titanium oxides, more preferably at least one of titanium tetrachloride, titanium nitrate, titanium sulfate, and titanium dioxide.

[0042] In this invention, the range of non-metallic M sources in the active component source slurry is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the non-metallic M source is selected from salts and / or acids containing non-metallic M, more preferably at least one of ammonium pentaborate, boric acid, ammonium dihydrogen phosphate, and phosphoric acid.

[0043] In this invention, the range of metal N sources in the active component source slurry is relatively wide. The following is an illustrative description, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the metal N source is selected from salts and / or oxides containing metal N, and more preferably at least one of ammonium molybdate, molybdenum oxide, ammonium metatungstate, silver nitrate, and niobium oxalate.

[0044] In this invention, there are no special requirements for the form in which the polymer compound is added. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the polymer compound is provided in solution form.

[0045] In this invention, there are no special requirements for the process of forming the active component source slurry. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the process of forming the active component source slurry includes: dissolving the active component source compound to form a pre-slurry, and mixing the pre-slurry with a polymer compound solution.

[0046] In this invention, the concentration of the polymer compound solution can be selected from a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the concentration of the polymer compound solution is 5-40 wt%, preferably 5-20 wt%.

[0047] In this invention, the mass ratio of the pre-slurry to the polymer compound solution can be selected within a wide range. The following is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the mass ratio of the pre-slurry to the polymer compound solution is 1:0.1-5, preferably 1:1-2. In the embodiments of the invention, the mass ratios of the pre-slurry to the polymer compound solution of 1:0.1, 1:2, and 1:3 are used as examples to illustrate the advantages of the invention, but they do not limit the scope of the invention.

[0048] In this invention, the solvent for the polymer compound solution has a wide range of options, specifically selected according to the type of polymer compound. The following is an illustrative example, but does not limit the scope of the invention. According to a preferred embodiment of the invention, the solvent for the polymer compound solution is selected from one or more of water, organic alcohols, and organic acids, preferably water. In the embodiments of this invention, ethanol and water are used as examples to illustrate the advantages of the invention, but do not limit the scope of the invention.

[0049] In this invention, there are no special requirements for the mixing method of forming the active component source slurry. Conventional mixing methods in the art can achieve the purpose of this invention. In the embodiments of this invention, stirring and mixing are used as an example to illustrate the advantages of this invention, but this does not limit the scope of this invention.

[0050] In this invention, there are no special requirements for the temperature at which the active component source slurry is formed. It is sufficient to allow the active component source slurry to fully dissolve, generally 50-100°C, etc. In this embodiment of the invention, the temperature at which the active component source slurry is formed is 90°C as an example to illustrate the advantages of the invention, but this does not limit the scope of the invention.

[0051] In this invention, the method of loading the active component source slurry onto the carrier is quite versatile. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the active component source slurry is loaded onto the carrier by spraying. The above is an illustrative description, but it does not limit the scope of the invention.

[0052] In this invention, there are no special requirements for the roasting temperature. Conventional roasting temperatures in the art can be used to achieve this invention, generally 400-600℃. In this embodiment of the invention, the roasting temperature is 500℃ as an example to illustrate the advantages of the invention, but this does not limit the scope of the invention.

[0053] In this invention, there are no special requirements for the roasting time, which is adjusted according to the roasting temperature. For example, the roasting time is generally 1-10 hours.

[0054] This invention provides the application of the catalyst described herein in the oxidation of aromatic hydrocarbons, preferably in the oxidation of polycyclic aromatic hydrocarbons.

[0055] The present invention provides a method for synthesizing naphthoquinone, the method comprising: reacting raw material naphthalene and / or alkylnaphthalene with an oxidant in the presence of the catalyst described in the present invention.

[0056] In this invention, the temperature range of the contact reaction is relatively wide. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the temperature of the contact reaction is 400-500°C, preferably 450-480°C.

[0057] In this invention, the mass hourly space velocity (MHSV) of the contacting reaction raw materials can be selected within a wide range. The following is an illustrative description, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the MHSV of the contacting reaction raw materials is 0.02-10 h⁻¹. -1 .

[0058] In this invention, the reaction apparatus for the contact reaction has no special requirements, and commonly used apparatuses are applicable to this invention. For example, the contact reaction is carried out in a fixed-bed reactor.

[0059] In this invention, the range of oxidants is relatively wide, and commonly used oxidants can be applied to this invention. For example, the oxidant is selected from one or more oxidizing gases, preferably oxygen and / or air, and more preferably air.

[0060] The vanadium-titanium catalyst described in this invention has high reactivity and can effectively improve reactant conversion and product selectivity when applied to oxidation reactions. When this vanadium-titanium catalyst is applied to the synthesis of naphthoquinone, the synthesis method is green and environmentally friendly, and the yield of naphthoquinone product is effectively improved, showing good prospects for industrial application.

[0061] The present invention will be described in detail below through examples. In the following examples, the active phase scale parameters were measured by scanning electron microscopy.

[0062]

Example 1

[0063] 110g of oxalic acid and 300ml of distilled water were weighed into a flask, stirred, and heated to 90℃ to prepare an oxalic acid solution. 94g of ammonium metavanadate was added to the prepared oxalic acid solution and stirred to obtain an ammonium oxalate oxyvanadate solution. Then, 10g of ammonium molybdate, 1.2g of phosphoric acid, and 132g of anatase titanium dioxide were added to the ammonium oxalate oxyvanadate solution and stirred to form a pre-slurry. The pre-slurry was mixed with a 16wt% aqueous solution of polyacrylic acid (degree of polymerization of 1500) at a mass ratio of 1:2 to obtain the active component source slurry. The active component source slurry was sprayed onto an α-Al₂O₃ support and calcined at 500℃ for 4 hours to obtain a solid oxide catalyst. The mass ratio of the active phase to the support was 0.15, and the active phase size was 90 micrometers as determined by SEM.

[0064] 1,4-Naphthoquinone was prepared using naphthalene and air as raw materials in a fixed-bed reactor in the presence of the above-mentioned catalyst at a temperature of 450°C and a naphthalene mass hourly space velocity of 5 h⁻¹. -1 The conversion rate of naphthalene was 85%, and the yield of 1,4-naphthoquinone was 78%.

[0065] 2-Methyl-1,4-naphthoquinone was prepared using 2-methylnaphthalene and air as raw materials in a fixed-bed reactor in the presence of the above-mentioned catalyst at a temperature of 465℃ and a mass hourly space velocity (WHSV) of 5 h⁻¹ for 2-methylnaphthalene. -1 The conversion rate of 2-methylnaphthalene was 89%, and the yield of 2-methyl-1,4-naphthoquinone was 76%.

[0066]

Example 2

[0067] 110g of oxalic acid and 300ml of distilled water were weighed into a flask, stirred, and heated to 90℃ to prepare an oxalic acid solution. 94g of ammonium metavanadate was added to the prepared oxalic acid solution and stirred to obtain an ammonium oxalate oxyvanadate solution. Then, 10g of ammonium molybdate, 1.2g of phosphoric acid, and 132g of anatase titanium dioxide were added to the ammonium oxalate oxyvanadate solution and stirred to form a pre-slurry. The pre-slurry was mixed with a 16wt% aqueous solution of polyacrylic acid (degree of polymerization of 1500) at a mass ratio of 1:3 to obtain the active component source slurry. The active component source slurry was sprayed onto an α-Al₂O₃ support and calcined at 500℃ for 4 hours to obtain a solid oxide catalyst. The mass ratio of the active phase to the support was 0.15, and the active phase size was 70 micrometers as determined by SEM.

[0068] 1,4-Naphthoquinone was prepared using naphthalene and air as raw materials in a fixed-bed reactor in the presence of the above-mentioned catalyst at a temperature of 460 °C and a naphthalene mass hourly space velocity of 5 h⁻¹. -1 The conversion rate of naphthalene was 82%, and the yield of 1,4-naphthoquinone was 76%.

[0069] 2-Methyl-1,4-naphthoquinone was prepared in a fixed-bed reactor using 2-methylnaphthalene and air as raw materials, in the presence of the catalyst described above, at a temperature of 475 °C and a mass hourly space velocity (WHSV) of 5 h⁻¹ for 2-methylnaphthalene. -1 The conversion rate of 2-methylnaphthalene was 86%, and the yield of 2-methyl-1,4-naphthoquinone was 72%.

[0070]

Example 3

[0071] 110g of oxalic acid and 300ml of distilled water were weighed into a flask, stirred, and heated to 90℃ to prepare an oxalic acid solution. 94g of ammonium metavanadate was added to the prepared oxalic acid solution and stirred to obtain an ammonium oxalate oxyvanadate solution. Then, 10g of ammonium molybdate, 1.2g of phosphoric acid, and 132g of anatase titanium dioxide were added to the ammonium oxalate oxyvanadate solution and stirred to form a pre-slurry. The pre-slurry was mixed with a 16wt% aqueous solution of polyacrylic acid (degree of polymerization of 1500) at a mass ratio of 1:0.1 to obtain the active component source slurry. The active component source slurry was sprayed onto an α-Al₂O₃ support and calcined at 500℃ for 4 hours to obtain a solid oxide catalyst. The mass ratio of the active phase to the support was 0.15, and the active phase size was 140 micrometers as determined by SEM.

[0072] 1,4-Naphthoquinone was prepared using naphthalene and air as raw materials in a fixed-bed reactor in the presence of the above-mentioned catalyst at a temperature of 470 °C and a naphthalene mass hourly space velocity of 5 h⁻¹. -1 The conversion rate of naphthalene was 79%, and the yield of 1,4-naphthoquinone was 72%.

[0073] 2-Methyl-1,4-naphthoquinone was prepared using 2-methylnaphthalene and air as raw materials in a fixed-bed reactor in the presence of the above-mentioned catalyst at a temperature of 485℃ and a mass hourly space velocity (WHSV) of 5 h⁻¹ for 2-methylnaphthalene. -1 The conversion rate of 2-methylnaphthalene was 81%, and the yield of 2-methyl-1,4-naphthoquinone was 69%.

[0074]

Example 4

[0075] The method and steps were the same as in Example 1, except that the polymer compound was dodecyl polyoxyethylene ether (degree of polymerization 1500), the mass ratio of the active phase to the support was 0.15, and the size of the active phase was 80 micrometers as determined by SEM.

[0076] Using naphthalene as a raw material, the conversion rate of naphthalene was 84%, and the yield of 1,4-naphthoquinone was 77%.

[0077] Using 2-methylnaphthalene as a raw material, the conversion rate of 2-methylnaphthalene was 88%, and the yield of 2-methyl-1,4-naphthoquinone was 74%.

[0078]

Example 5

[0079] The method steps are the same as in Example 1, except that the polymer compound is polystyrene sulfonic acid (degree of polymerization is 1500), the mass ratio of active phase to support is 0.15, and the size of the active phase is 85 micrometers as determined by SEM.

[0080] Using naphthalene as a raw material, the conversion rate of naphthalene was 84%, and the yield of 1,4-naphthoquinone was 76%.

[0081] Using 2-methylnaphthalene as a raw material, the conversion rate of 2-methylnaphthalene was 87%, and the yield of 2-methyl-1,4-naphthoquinone was 73%.

[0082]

Example 6

[0083] The method and steps of Example 1 were followed, except that 35 wt% polyacrylic acid was added, the mass ratio of the active phase to the carrier was 0.15, and the size of the active phase was 40 micrometers as determined by SEM testing.

[0084] Using naphthalene as a raw material, the conversion rate of naphthalene was 72%, and the yield of 1,4-naphthoquinone was 68%.

[0085] Using 2-methylnaphthalene as a raw material, the conversion rate of 2-methylnaphthalene was 75%, and the yield of 2-methyl-1,4-naphthoquinone was 66%.

[0086]

Example 7

[0087] The method steps of Example 1 were followed, except that a polyacrylate ethanol solution was added, the mass ratio of the active phase to the carrier was 0.15, and the size of the active phase was 50 micrometers as determined by SEM testing.

[0088] Using naphthalene as a raw material, the conversion rate of naphthalene was 79%, and the yield of 1,4-naphthoquinone was 70%.

[0089] Using 2-methylnaphthalene as a raw material, the conversion rate of 2-methylnaphthalene was 81%, and the yield of 2-methyl-1,4-naphthoquinone was 67%.

[0090]

Example 8

[0091] The method steps of Example 1 were followed, except that an aqueous solution of polyacrylic acid and polystyrene sulfonic acid (each with a content of 50 wt%) with a concentration of 16 wt% was added, the mass ratio of the active phase to the carrier was 0.15, and the size of the active phase was 95 micrometers as determined by SEM testing.

[0092] Using naphthalene as a raw material, the conversion rate of naphthalene was 88%, and the yield of 1,4-naphthoquinone was 80%.

[0093] Using 2-methylnaphthalene as a raw material, the conversion rate of 2-methylnaphthalene was 90%, and the yield of 2-methyl-1,4-naphthoquinone was 78%.

[0094] Comparative Example 1

[0095] The method of Example 1 was followed, except that an aqueous polyacrylic acid solution was not added; instead, the pre-slurry was used directly for spraying, while all other conditions remained the same. The mass ratio of the active phase to the carrier was 0.15, and the size of the active phase was 190 micrometers as determined by SEM.

[0096] 1,4-Naphthoquinone was prepared using naphthalene and air as raw materials in a fixed-bed reactor in the presence of the above-mentioned catalyst at a temperature of 470 °C and a naphthalene mass hourly space velocity of 5 h⁻¹. -1 The conversion rate of naphthalene was 68%, and the yield of 1,4-naphthoquinone was 55%.

[0097] Using 2-methylnaphthalene and air as raw materials, a fixed-bed reactor was used to prepare 2-methyl-1,4-naphthoquinone in the presence of the above catalyst at a temperature of 485℃. The mass hourly space velocity (WHSV) of 2-methylnaphthalene was 5, the conversion rate of 2-methylnaphthalene was 70%, and the yield of 2-methyl-1,4-naphthoquinone was 51%.

[0098] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A vanadium-titanium catalyst, characterized by, The catalyst comprises a support and an active phase, wherein the active phase comprises vanadium and titanium, and the size of the active phase is 50-150 micrometers; the mass ratio of the active phase to the support is 0.03-0.

30.

2. The catalyst according to claim 1, wherein, The carrier is selected from at least one of α-alumina, ceramic rings, and silicon carbide; and / or The molar ratio of titanium to vanadium is 1-50; and / or The active phase has a size of 60-100 micrometers; and / or The mass ratio of the active phase to the support is 0.1-0.

2.

3. The catalyst of claim 1 or 2, wherein, The active phase also includes non-metallic element M and / or metallic element N. Preferably, The nonmetallic element M is selected from at least one nonmetallic element from Group IIIA, Group VA, and Group VIA; preferably, the nonmetallic element M is selected from at least one element from B, N, P, S, and Se, more preferably from at least one element from B, N, and P; and / or The metal element N is selected from at least one metal element from Group IA, Group IIIA, Group VA, Group IB, Group IIIB, Group VB, Group VIB, and Group VIII; preferably, the metal element N is selected from at least one element from Li, Na, K, Cs, In, Sb, Bi, Ag, Au, Ce, Nd, Nb, Cr, Mo, W, Fe, Co, and Ir, and more preferably, it is selected from at least one element from Ce, Mo, and W; Preferably, The molar ratio of the nonmetallic element M to vanadium is 0.001-0.1; and / or The molar ratio of the metallic element N to vanadium is 0.001-0.

05.

4. The catalyst of any one of claims 1-3, wherein, The active phase has a component elemental composition of V-Ti. a -M b -N c -O x The value of a ranges from 1 to 50, the value of b ranges from 0.001 to 0.1, the value of c ranges from 0.001 to 0.05, and x is the total number of oxygen atoms required to satisfy the oxidation states of each element in the catalyst.

5. A process for the preparation of the vanadium-titanium catalyst according to any one of claims 1 to 4, characterized in that, The method includes: (1) Forming an active component source slurry, wherein the active component source slurry contains a polymer compound, wherein the polymer compound is selected from nonionic polymer compounds and / or anionic polymer compounds; (2) The active component source slurry is brought into contact with the carrier for loading, and the resulting solid is calcined.

6. The preparation method according to claim 5, wherein, The nonionic polymer compound is selected from polyenol polymers and / or polyether polymers; preferably at least one of poly(C2-C6) enols, C2-C18 alkyl polyoxygenated C2-C4 alkenyl ethers, and bis(C2-C18) alkyl polyethers; more preferably at least one of poly(C2-C3) enols, C9-C12 alkyl polyoxygenated C2-C3 alkenyl ethers, and bis(C9-C12) alkyl polyethers. and / or The anionic polymer compound is selected from carboxylic acid polymers and / or sulfonic acid polymers; preferably at least one of poly(C3-C6) olefinic acid, C3-C6 olefinic acid copolymer, polystyrene sulfonic acid, benzenesulfonic acid formaldehyde condensate, and sodium lignosulfonate; more preferably at least one of poly(C3-C5) olefinic acid, acrylic acid maleic anhydride copolymer, polystyrene sulfonic acid, and sodium lignosulfonate; even more preferably poly(C3-C6) olefinic acid and polystyrene sulfonic acid, each with a content of not less than 20 wt%, preferably each with a content of 30-70 wt%; and / or The degree of polymerization of the polymer compound is 10-2000; and / or The mass ratio of the polymer compound to the vanadium source compound in the active component slurry is 0.1-5:1, preferably 1-3:

1.

7. The production method according to claim 5 or 6, wherein In the active component source slurry The vanadium source is selected from vanadium salts and / or vanadium oxides, more preferably from at least one of ammonium metavanadate, vanadium oxalate, and vanadium pentoxide; and / or The titanium source is selected from titanium salts and / or titanium oxides, more preferably at least one of titanium tetrachloride, titanium nitrate, titanium sulfate, and titanium dioxide; and / or The nonmetallic source M is selected from salts and / or acids containing nonmetal M, more preferably at least one of ammonium pentaborate, boric acid, ammonium dihydrogen phosphate, and phosphoric acid; and / or The metal N source is selected from salts and / or oxides containing metal N, more preferably at least one of ammonium molybdate, molybdenum oxide, ammonium metatungstate, silver nitrate, and niobium oxalate.

8. The preparation method according to any one of claims 5-7, wherein, The process of forming an active component source slurry includes: dissolving the active component source compound to form a pre-slurry, and mixing the pre-slurry with a polymer compound solution; Preferably, The concentration of the polymer solution is 5-40 wt%, preferably 5-20 wt%; and / or The mass ratio of the pre-slurry to the polymer compound solution is 1:0.1-5, preferably 1:1-2; and / or The solvent for the polymer compound solution is selected from one or more of water, organic alcohols, and organic acids, preferably water.

9. The use of the catalyst according to any one of claims 1-4 in the oxidation of aromatic hydrocarbons, preferably in the oxidation of polycyclic aromatic hydrocarbons.

10. A method of synthesizing naphthoquinone, characterized by, The method comprises: reacting a raw material naphthalene and / or alkylnaphthalene with an oxidant in the presence of a catalyst as described in any one of claims 1-4; Preferably, The conditions for the contact reaction include: The temperature is 400-500℃, preferably 450-480℃; and / or The mass space velocity of the feedstock is 0.02-10 h -1 ; and / or The reaction is carried out in a fixed-bed reactor; and / or The oxidant is selected from one or more oxidizing gases, preferably oxygen and / or air.