Preparation method and application of P-modified Fe-coated ZSM core-shell structure catalyst

Abstract

The invention relates to a preparation method and application of a P-modified Fe-coated ZSM core-shell structure catalyst, and belongs to the field of catalysts. The preparation method of the catalyst comprises preparation of an Fe-MOF precursor and preparation of a P-modified Fe-coated ZSM core-shell structure catalyst. According to the invention, P modification and formation of the catalyst with the core-shell structure are simultaneously carried out, and the specific phosphorus source, the organic ligand, the pore forming agent and the noble metal salt are screened out to prepare the catalyst, so that the catalytic activity, the service life and the storage stability of the catalyst are greatly improved, and the catalyst has excellent unexpected technical effects.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of catalysts, in particular to a preparation method of a P-modified Fe@ZSM core-shell structure catalyst and application thereof. BACKGROUND

[0002] Currently, the catalyst for preparing 1,1,1,3-tetrachloropropane by reacting ethylene and carbon tetrachloride is mainly a combination of iron powder, ferric chloride and organic phosphorus compounds.

[0003] (1) Iron powder: US patent application US4605802A provides a synthesis method of 1,1,1,3-tetrachloropropane, which uses iron powder as a catalyst. The carbon tetrachloride conversion rate of this method is 45% or more, and the selectivity is 95% or more. However, this method uses iron powder as the main catalyst, and the surface will form an oxide film after long-term contact with air, affecting the service life of the catalyst.

[0004] (2) Ferric chloride or / and phosphate esters: Chinese patent application CN1488614A uses ferric chloride or / and phosphate esters as catalysts. This method has the problems of low conversion rate and selectivity.

[0005] (3) Supported iron catalyst and phosphate esters: Chinese patent application CN114605226A discloses a method for continuously synthesizing 1,1,1,3-tetrachloropropane. This method uses a catalyst with a porous support material loaded with an iron catalyst to catalyze the preparation of 1,1,1,3-tetrachloropropane from carbon tetrachloride and ethylene. The carbon tetrachloride conversion rate of this method is 80% or more, and the selectivity is 90% or more. However, this method still needs to use phosphate esters as a cocatalyst, still needs to rely on liquid catalytic additives, and the catalyst has the problem of short service life.

[0006] Therefore, there is still an urgent need for a catalyst with high carbon tetrachloride conversion rate, high 1,1,1,3-tetrachloropropane selectivity, long service life and good storage stability. SUMMARY

[0007] The present application aims to at least partially solve one of the technical problems in the related art.

[0008] To this end, the first aspect of the present application provides a preparation method of a catalyst, comprising the following steps:

[0009] S1: Fe-MOF precursor preparation: dissolving an iron source in water to obtain an iron source solution; dissolving a phosphorus source, an organic ligand and a pore-forming agent in an organic solvent to obtain solution A; adding the iron source solution to solution A, heating and reacting, washing, centrifuging or filtering, obtaining a solid, drying the solid to obtain a Fe-MOF precursor;

[0010] S2: Preparation of the P-modified Fe@ZSM core-shell structure catalyst: the Fe-MOF precursor obtained in step S1 was dispersed in water, and a surfactant, an aluminum source, and a palladium source were added to obtain solution B; a silicon source was dissolved in an aqueous ammonia solution to obtain a silicon source solution; the silicon source solution was added to solution B, the pH was adjusted, and stirring was performed, and a solid was precipitated, washed, dried, calcined, and reduced at room temperature in a hydrogen atmosphere to obtain the P-modified Fe@ZSM core-shell structure catalyst, i.e., the catalyst.

[0011] In some embodiments, the iron source includes at least one of ferric chloride or a hydrate thereof, ferric nitrate or a hydrate thereof, ferric sulfate or a hydrate thereof, and ferric citrate.

[0012] In some embodiments, the iron source includes at least one of ferric chloride hexahydrate, ferric nitrate heptahydrate, ferric sulfate nonahydrate, and ferric citrate.

[0013] In some embodiments, the phosphorus source includes at least one of phosphoric acid, trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, triethyl phosphite, and triphenylphosphine. In some preferred embodiments, the phosphorus source is trimethyl phosphate.

[0014] In some embodiments, the organic ligand includes at least one of terephthalic acid, trimesic acid, trimellitic acid, and 2-hydroxyterephthalic acid. In some preferred embodiments, the organic ligand is terephthalic acid.

[0015] In some embodiments, the pore-forming agent includes at least one of benzoic acid, formic acid, oxalic acid, sodium formate, and sodium acetate. In some preferred embodiments, the pore-forming agent is formic acid.

[0016] In some embodiments, the organic solvent includes at least one of N,N-dimethylformamide, ethanol, and methanol.

[0017] In some embodiments, the concentration of the iron source in the iron source solution is 1.25 mol / L-2.50 mol / L. In some embodiments, the concentration of the iron source in the iron source solution is 1.25 mol / L, 1.50 mol / L, 1.75 mol / L, 2.00 mol / L, 2.25 mol / L, or 2.50 mol / L.

[0018] In some embodiments, the phosphorus source is dosed at 1.25 mmol - 5.00 mmol per 100 mL of the organic solvent. In some embodiments, the phosphorus source is dosed at 1.25 mmol - 3.75 mmol per 100 mL of the organic solvent. In some embodiments, the phosphorus source is dosed at 1.25 mmol, 1.50 mmol, 1.75 mmol, 2.00 mmol, 2.50 mmol, 3.00 mmol, 3.50 mmol, 3.75 mmol, 4.00 mmol, 4.50 mmol, or 5.00 mmol per 100 mL of the organic solvent.

[0019] In some embodiments, the iron source and the organic ligand are dosed at a molar ratio of 1 :2 - 2: 1. In some embodiments, the iron source and the organic ligand are dosed at a molar ratio of 1 : 1.5 - 1.5: 1. In some embodiments, the iron source and the organic ligand are dosed at a molar ratio of 1 :2, 1 : 1.5, 1 : 1, 1.5: 1, or 2: 1.

[0020] In some embodiments, the organic ligand and the pore former are dosed at a molar ratio of 1 :5 - 5: 1. In some embodiments, the organic ligand and the pore former are dosed at a molar ratio of 1 :2.5 - 2.5: 1. In some embodiments, the organic ligand and the pore former are dosed at a molar ratio of 1 :5, 1 :4.5, 1 :4, 1 :3.5, 1 :3, 1 :2.5, 1 :2, 1 : 1.5, 1 : 1, 1.5: 1, 2: 1, 2.5: 1, 3: 1, 3.5: 1, 4: 1, 4.5: 1, or 5: 1.

[0021] In some embodiments, the iron source and the phosphorus source are dosed at a molar ratio of 1000: 1 - 100:3. In some embodiments, the iron source and the phosphorus source are dosed at a molar ratio of 100: 1 - 100:3. In some embodiments, the iron source and the phosphorus source are dosed at a molar ratio of 1000: 1, 500: 1, 200: 1, 150: 1, 100: 1, 100: 1.5, 100:2, 100:2.5, or 100:3.

[0022] In some embodiments, the heating reaction is performed at a temperature of 80 °C - 150 °C. In some embodiments, the heating reaction is performed at a temperature of 120 °C - 150 °C. In some embodiments, the heating reaction is performed at a temperature of 130 °C - 150 °C. In some embodiments, the heating reaction is performed at a temperature of 80 °C, 85 °C, 90 °C, 95 °C, 100 °C, 105 °C, 110 °C, 115 °C, 120 °C, 125 °C, 130 °C, 135 °C, 140 °C, 145 °C, or 150 °C.

[0023] In some embodiments, the heating reaction comprises a microwave-assisted solvothermal reaction.

[0024] In some embodiments, the heating reaction has a reaction time of 0.5 h to 24 h. In some embodiments, the heating reaction has a reaction time of 10 h to 24 h. In some embodiments, the heating reaction has a reaction time of 12 h to 20 h. In some embodiments, the heating reaction has a reaction time of 0.5 h, 1 h, 5 h, 10 h, 11 h, 12 h, 13 h, 14 h, 15 h, 16 h, 17 h, 18 h, 19 h, 20 h, 21 h, 22 h, 23 h, or 24 h.

[0025] In some embodiments, the washing in step S1 comprises washing with ethanol and water, respectively.

[0026] In some embodiments, the washing in step S1 comprises washing with ethanol and water, each for 1 to 5 times (e.g., 1 time, 2 times, 3 times, 4 times, 5 times).

[0027] In some embodiments, the surfactant comprises at least one of ammonium lauryl sulfate or sodium cetyl sulfonate.

[0028] In some embodiments, the aluminum source comprises at least one of aluminum trichloride or a hydrate thereof, aluminum sulfate or a hydrate thereof, aluminum ammonium sulfate or a hydrate thereof.

[0029] In some embodiments, the aluminum trichloride or a hydrate thereof comprises aluminum trichloride or aluminum trichloride hexahydrate.

[0030] In some embodiments, the silicon source comprises at least one of a metal salt of metasilicic acid (e.g., sodium metasilicate), silicon dioxide, a metal salt of fluorosilicic acid, a metal salt of orthosilicic acid, a metal salt of silicic acid, a metal salt of orthodisilicic acid, a metal salt of disilicic acid, or a metal salt of trisilicic acid.

[0031] In some embodiments, the palladium source comprises at least one of palladium chloride or a hydrate thereof, palladium nitrate or a hydrate thereof.

[0032] In some embodiments, the mass ratio of Pd element in the palladium source to Fe element in the iron source is 0.005:1 to 0.05:1. In some embodiments, the mass ratio of Pd element in the palladium source to Fe element in the iron source is 0.01:1 to 0.05:1. In some embodiments, the mass ratio of Pd element in the palladium source to Fe element in the iron source is 0.005:1, 0.01:1, 0.02:1, 0.03:1, 0.04:1, or 0.05:1.

[0033] In some embodiments, the molar ratio of the silicon source to the surfactant is 10000:1 to 500:1. In some embodiments, the molar ratio of the silicon source to the surfactant is 3000:1 to 1000:1. In some embodiments, the molar ratio of the silicon source to the surfactant is 10000:1, 9000:1, 8000:1, 7000:1, 6000:1, 5000:1, 4000:1, 3000:1, 2500:1, 2400, 2300:1, 2200:1, 2100:1, 2000:1, 1900:1, 1800:1, 1700:1, 1600:1, 1500:1, 1000:1, 500:1.

[0034] In some embodiments, the molar ratio of Si atoms in the silicon source to Al atoms in the aluminum source is (5-100):1. In some embodiments, the molar ratio of Si atoms in the silicon source to Al atoms in the aluminum source is 15:1 to 20:1. In some embodiments, the molar ratio of Si atoms in the silicon source to Al atoms in the aluminum source is 5:1, 10:1, 15:1, 16:1, 17:1, 18:1, 19:1, 20:1, 21:1, 22:1, 23:1, 24:1, 25:1, 30:1, 40:1, 50:1, 60:1, 70:1, 80:1, 90:1, or 100:1. In some embodiments, the molar ratio of Si atoms in the silicon source to Al atoms in the aluminum source is 19:1.

[0035] In some embodiments, the concentration of ammonia in the aqueous ammonia solution is 25wt% to 28wt%. In some embodiments, the concentration of ammonia in the aqueous ammonia solution is 25wt%, 26wt%, 27wt%, or 28wt%.

[0036] In some embodiments, the adjusting the pH is adjusting the pH to 8 to 9. In some embodiments, the adjusting the pH is adjusting the pH to 8, 8.5, or 9.

[0037] In some embodiments, the calcining comprises: prior to the calcining in an air atmosphere.

[0038] In some embodiments, the calcining in an air atmosphere is at a temperature of 450°C to 700°C. In some embodiments, the calcining in an air atmosphere is at a temperature of 450°C, 500°C, 550°C, 600°C, 650°C, or 700°C.

[0039] In some embodiments, the calcining in an air atmosphere is for a time of 3h to 5h. In some embodiments, the calcining in an air atmosphere is for a time of 3h, 4h, or 5h.

[0040] In some embodiments, the heating rate of the calcination in the air atmosphere is 1℃ / min-5℃ / min. In some embodiments, the heating rate of the calcination in the air atmosphere is 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min or 5℃ / min.

[0041] In some embodiments, the temperature of the heating reduction in the hydrogen atmosphere is 300℃-500℃. In some embodiments, the temperature of the heating reduction in the hydrogen atmosphere is 400℃-500℃. In some embodiments, the temperature of the heating reduction in the hydrogen atmosphere is 300℃, 350℃, 400℃, 450℃ or 500℃.

[0042] In some embodiments, the heating reduction time of the heating reduction in the hydrogen atmosphere is 0.5h-2h. In some embodiments, the heating reduction time of the heating reduction in the hydrogen atmosphere is 0.5h, 1h, 1.5h or 2h.

[0043] In some embodiments, the heating rate of the heating reduction in the hydrogen atmosphere is 1℃ / min-5℃ / min. In some embodiments, the heating rate of the heating reduction in the hydrogen atmosphere is 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min or 5℃ / min.

[0044] In a second aspect, the present application provides a catalyst prepared by the preparation method of the first aspect.

[0045] In a third aspect, the present application provides an application of the catalyst prepared by the preparation method of the first aspect or the catalyst of the second aspect in catalyzing a reaction of carbon tetrachloride and ethylene to prepare 1,1,1,3-tetrachloropropane.

[0046] In a fourth aspect, the present application provides a synthesis method of 1,1,1,3-tetrachloropropane, which comprises:

[0047]

[0048] Carbon tetrachloride and ethylene react in the presence of the catalyst of the second aspect to obtain 1,1,1,3-tetrachloropropane.

[0049] In some embodiments, the reaction temperature of the reaction is 80℃-130℃. In some embodiments, the reaction temperature of the reaction is 100℃-130℃. In some embodiments, the reaction temperature of the reaction is 80℃, 85℃, 90℃, 95℃, 100℃, 105℃, 110℃, 115℃, 120℃, 125℃ or 130℃.

[0050] In some preferred embodiments, the reaction is carried out under the condition that the ethylene gas pressure is 0.5-1.5 MPa. In some embodiments, the reaction is carried out under the condition that the ethylene gas pressure is 0.6-1.4 MPa. In some embodiments, the reaction is carried out under the condition that the ethylene gas pressure is 0.7-1.3 MPa. In some embodiments, the reaction is carried out under the condition that the ethylene gas pressure is 0.7-1.2 MPa. In some preferred embodiments, the reaction is carried out under the condition that the ethylene gas pressure is 0.8-1.1 MPa.

[0051] Compared with the prior art, the technical scheme of the present application has the following beneficial technical effects:

[0052] (1) The catalyst provided by the present application has high catalytic activity, high selectivity, long service life and high storage stability, and has excellent unexpected technical effects.

[0053] (2) Compared with the catalyst without P modification, the catalyst of the present application is P modified. The use of the P modified catalyst provided by the present application to catalyze the reaction of carbon tetrachloride and ethylene to prepare 1,1,1,3,-tetrachloropropane can greatly improve the carbon tetrachloride conversion rate, the service life and the storage stability of the catalyst, and has unexpected technical effects.

[0054] (3) Compared with the catalyst without core-shell structure, the use of the catalyst with core-shell structure provided by the present application can greatly improve the carbon tetrachloride conversion rate, the service life and the storage stability of the catalyst in the reaction of carbon tetrachloride and ethylene to prepare 1,1,1,3,-tetrachloropropane, and has unexpected technical effects.

[0055] (4) The P modification and the core-shell structure of the present application are mutually synergistic. The use of the catalyst provided by the present application, which is simultaneously P modified and has a core-shell structure, can greatly improve the carbon tetrachloride conversion rate in the reaction of carbon tetrachloride and ethylene to prepare 1,1,1,3,-tetrachloropropane, and greatly improve the service life and the storage stability of the obtained catalyst, and has unexpected technical effects.

[0056] (5) Compared with the use of other phosphorus sources (such as triethyl phosphate or tributyl phosphate), the use of the catalyst prepared by using trimethyl phosphate as the phosphorus source according to the present application can greatly improve the carbon tetrachloride conversion rate and the selectivity of 1,1,1,3,-tetrachloropropane in the reaction of carbon tetrachloride and ethylene to prepare 1,1,1,3,-tetrachloropropane, and greatly improve the service life and the storage stability of the obtained catalyst, and has unexpected technical effects.

[0057] (6) Compared with other organic ligands (such as trimesic acid or 2-amino terephthalic acid), the catalyst prepared by using terephthalic acid as the organic ligand can greatly improve the carbon tetrachloride conversion rate and the 1,1,1,3,-tetra-chloropropane selectivity in the reaction of carbon tetrachloride and ethylene to prepare 1,1,1,3,-tetra-chloropropane, and greatly improve the service life and storage stability of the obtained catalyst, and has unexpected technical effects.

[0058] (7) Compared with other pore-forming agents (such as benzoic acid or oxalic acid), the catalyst prepared by using formic acid as the pore-forming agent can greatly improve the carbon tetrachloride conversion rate and the 1,1,1,3,-tetra-chloropropane selectivity in the reaction of carbon tetrachloride and ethylene to prepare 1,1,1,3,-tetra-chloropropane, and greatly improve the service life and storage stability of the obtained catalyst, and has unexpected technical effects.

[0059] (8) Compared with other noble metal salts (such as platinum nitrate or rhodium nitrate), the catalyst prepared by using palladium nitrate as the noble metal salt can greatly improve the 1,1,1,3,-tetra-chloropropane selectivity in the reaction of carbon tetrachloride and ethylene to prepare 1,1,1,3,-tetra-chloropropane, and greatly improve the service life and storage stability of the obtained catalyst, and has unexpected technical effects.

[0060] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following description, or can be learned by practice of the application. DETAILED DESCRIPTION

[0061] Embodiments of the present application are described in detail below. The embodiments described below are exemplary only and are not intended to limit the present application, which can be understood only by the description.

[0062] It should be noted that the terms "first", "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. Further, in the description of the present application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0063] The endpoints of the ranges and any values described herein are not limited to the precise values stated. The ranges and values should be construed to be approximations that allow for significant variation. Various ranges of values are stated in terms of being between two specific values. When values are provided as between lower and upper values, this is intended to include the values from the lower and values to the upper, as well as any value between these values.

[0064] For the purposes of the present application, certain technical and scientific terms are specifically defined below. Unless specifically defined herein, all other technical and scientific terms used in the present document have the meanings that are commonly understood by one of ordinary skill in the art in the field of the present application.

[0065] In this document, the terms "comprising" or "comprise" do not, unless otherwise specified, exclude the presence of other elements or steps than those listed.

[0066] In this document, the terms "optional", "optionally" or "may" generally mean that the subsequently described event or circumstance can or can not occur, and the description includes instances where the event or circumstance occurs and instances where it does not.

[0067] The term "room temperature" means ambient temperature, referring to a temperature of about 10 °C to about 35 °C, or about 10 °C to about 30 °C, or about 20 °C to 30 °C, or about 25 °C.

[0068] In the following disclosure, all numbers disclosed herein are approximations that can vary depending on the desired properties sought to be obtained by those of ordinary skill in the art. The numerical parameters recited in this disclosure are approximations that can vary from the numerical parameters with 1%, 2%, 5%, 7%, 8%, 10%, 15%, or 20% of the numerical parameters. Unless otherwise stated, each numerical parameter recited in the specification and claims is approximations. Whenever a numerical range is indicated, it is meant to include all cited number within the indicated ranges. The use of "about" or "approximately" in connection with a recited numerical value means that the algebraic value of the quantity is within 10% of the recited value.

[0069] The schemes of the present application will be explained below with reference to Examples. Those skilled in the art will appreciate that the following Examples are intended to be illustrative only and should not be viewed as limiting the scope of the present application. Unless otherwise indicated in the Examples, the techniques or conditions were performed according to those described in the literature or according to the manufacturer's instructions. Unless otherwise indicated, the reagents or instruments used in the Examples were commercially available and were conventional products.

[0070] Example 1

[0071] Preparation of Fe-MOF precursor: 0.25 mol of iron chloride hexahydrate was dissolved in 200 ml of water to obtain an iron source solution. 2.5 mmol of phosphorus source (trimethyl phosphate), 0.25 mol of organic ligand (terephthalic acid), and 0.1 mol of pore-forming agent (formic acid) were dissolved in 200 ml of DMF to obtain solution A. The above iron source solution was added to solution A, and microwave-assisted solvothermal reaction was performed at 130°C for 12 h, followed by washing with ethanol and water each for 3 times, centrifugation or filtration to obtain a solid, drying the obtained solid to obtain a powder of Fe-MOF precursor.

[0072] Preparation of P-modified Fe@ZSM core-shell structure catalyst: the above obtained Fe-MOF precursor was dispersed in 200 ml of water with vigorous stirring and 2.5 mmol of ammonium lauryl sulfate, 0.26 mol of aluminum chloride, and 2.5 mmol of palladium nitrate were added to obtain solution B. 5.0 mol of sodium metasilicate was dissolved in 100 ml of aqueous ammonia solution, and the sodium metasilicate solution was slowly added to solution B, and the pH was adjusted to 8-9, stirred, washed with water, and dried at 80°C for 12 h. First, calcination was performed in air (calcination temperature was 500°C, calcination time was 3 h, and the temperature rising rate was 5°C / min). After being reduced at room temperature, reduction was performed under a hydrogen atmosphere (temperature was 400°C, reduction time was 0.5 h, and the temperature rising rate was 5°C / min). It is denoted as catalyst 1.

[0073] Example 2

[0074] Preparation of Fe-MOF precursor: 0.25 mol of iron chloride hexahydrate was dissolved in 200 ml of water to obtain an iron source solution. 2.5 mmol of phosphorus source (trimethyl phosphate), 0.25 mol of organic ligand (terephthalic acid), and 0.1 mol of pore-forming agent (formic acid) were dissolved in 200 ml of DMF to obtain solution A. The above iron source solution was added to solution A, and microwave-assisted solvothermal reaction was performed at 130°C for 12 h, followed by washing with ethanol and water each for 3 times, centrifugation or filtration to obtain a solid, drying the obtained solid to obtain a powder of Fe-MOF precursor.

[0075] Preparation of P modified Fe@ZSM core-shell structure catalyst: The above obtained all Fe-MOF precursor was dispersed in 200 ml water with vigorous stirring and 2.5 mmol of ammonium lauryl sulfate, 0.26 mol of aluminum chloride, 2.5 mmol of palladium nitrate was added, 5.0 mol of sodium metasilicate was dissolved in 100 ml of aqueous ammonia solution, the sodium metasilicate solution was slowly added to the Fe-MOF precursor solution, the pH was adjusted to 8-9, stirred, washed with water, and dried at 80°C for 12 h. First, calcination was carried out in air (calcination temperature was 500°C, calcination time was 3h, and the heating rate was 5°C / min). After cooling to room temperature, reduction was carried out in a hydrogen atmosphere (temperature was 400°C, reduction time was 0.5h, and the heating rate was 5°C / min). Denoted as catalyst 2.

[0076] Example 3: Microwave-assisted solvothermal reaction temperature investigation

[0077] Example 3: The difference from Example 1 is that the microwave-assisted solvothermal reaction temperature 130°C is replaced by 150°C, and the rest of the conditions are the same as Example 1.

[0078] Comparative Example 1: Catalyst without P modification

[0079] The difference from Example 1 is only that no phosphorus source (trimethyl phosphate) is added, and the rest of the operation is the same as Example 1.

[0080] Comparative Example 2: Catalyst without forming a core-shell structure

[0081] Preparation of Fe-MOF precursor: The Fe-MOF precursor in powder form was prepared according to the method of Example 1.

[0082] Preparation of catalyst: The obtained Fe-MOF precursor in powder form was first calcined in air, the temperature was 500°C, the heat treatment time was 3h, and the heating rate was 5°C / min. Then reduction was carried out in a hydrogen atmosphere, the temperature was 400°C, the heat treatment time was 0.5h, and the heating rate was 5°C / min. Denoted as catalyst 4.

[0083] Comparative Example 3-Comparative Example 4: Phosphorus source screening investigation

[0084] Comparative Example 3: The difference from Example 1 is that the phosphorus source (trimethyl phosphate) is replaced by triethyl phosphate, and the rest of the conditions are the same as Example 1.

[0085] Comparative Example 4: The difference from Example 1 is that the phosphorus source (trimethyl phosphate) is replaced by tributyl phosphate, and the rest of the conditions are the same as Example 1.

[0086] Comparative Example 5, Comparative Example 6: Organic ligand investigation

[0087] Comparative Example 5: The difference from Example 1 is that the organic ligand (terephthalic acid) is replaced by trimesic acid, and the rest of the conditions are the same as in Example 1.

[0088] Comparative Example 6: The difference from Example 1 is that the organic ligand (terephthalic acid) is replaced by 2-amino terephthalic acid, and the rest of the conditions are the same as in Example 1.

[0089] Comparative Examples 7, 8: Pore-forming agent screening investigation

[0090] Comparative Example 7: The difference from Example 1 is that the pore-forming agent (formic acid) is replaced by oxalic acid, and the rest of the conditions are the same as in Example 1.

[0091] Comparative Example 8: The difference from Example 1 is that the pore-forming agent (formic acid) is replaced by benzoic acid, and the rest of the conditions are the same as in Example 1.

[0092] Comparative Examples 9-10: Noble metal salt investigation

[0093] Comparative Example 9: The difference from Example 1 is that the palladium nitrate is replaced by platinum nitrate, and the rest of the conditions are the same as in Example 1.

[0094] Comparative Example 10: The difference from Example 1 is that the palladium nitrate is replaced by rhodium nitrate, and the rest of the conditions are the same as in Example 1.

[0095] Investigation Example 1: Catalytic activity, service life and storage stability evaluation:

[0096] Catalytic activity investigation: The high-pressure reaction kettle was evacuated to replace the air, then the catalyst to be investigated, 700 g of carbon tetrachloride, was charged with ethylene at 0.5 MPa, the temperature was set, and after reaching 100°C, ethylene was charged to 1.1 MPa. As the reaction proceeded, ethylene was supplemented to maintain the pressure at 0.8-1.1 MPa. The reaction was carried out for 4 h, and the cooling water was circulated to reduce the temperature. The conversion of carbon tetrachloride and the selectivity of 1,1,1,3,-tetra-chloropropane were analyzed by sampling, and the results are shown in Table 1.

[0097] Service life investigation: The method of “catalytic activity investigation” was continuously used for 10 times, and the decrease of the conversion of carbon tetrachloride and the selectivity of 1,1,1,3,-tetra-chloropropane in the 10th time were compared, and the results are shown in Table 2.

[0098] Storage stability investigation: The catalysts obtained in each example and comparative example were sealed and packaged with a self-sealing bag, and were placed at 45°C and 75% RH for 12 months. The conversion of carbon tetrachloride and the selectivity of 1,1,1,3,-tetra-chloropropane were detected, and the results are shown in Table 2.

[0099] Table 1: Conversion of carbon tetrachloride and selectivity of 1,1,1,3,-tetra-chloropropane

[0100] Catalyst source Carbon tetrachloride conversion 1,1,1,3,-tetrachloropropane selectivity Example 1 99.6％ 97.7％ Example 2 98.7％ 95.6％ Example 3 95.4％ 97.2％ Comparative Example 1 45.8％ 97.5％ Comparative Example 2 86.1％ 95.3％ Comparative Example 3 79.9％ 94.5％ Comparative Example 4 80.4％ 90.5％ Comparative Example 5 85.5％ 96.9％ Comparative Example 6 83.6％ 97.6％ Comparative Example 7 79.9％ 94.5％ Comparative Example 8 83.7％ 95.6％ Comparative Example 9 98.4％ 92.1％ Comparative Example 10 98.8％ 93.5％

[0101] Table 2: Service life and storage stability investigation

[0102]

[0103]

[0104] Result analysis:

[0105] (1) Compared with the catalyst without P modification (Comparative Example 1), the catalysts of the present application are P modified (Examples 1-3), and the catalysts provided by the present application which are P modified can greatly improve the carbon tetrachloride conversion rate, service life and storage stability of the catalyst in the reaction of preparing 1,1,1,3,-tetrachloropropane from carbon tetrachloride and ethylene, and have unexpected technical effects.

[0106] (2) Compared with the catalyst without core-shell structure (Comparative Example 2), the catalysts provided by the present application which form core-shell structure (Examples 1-3) can greatly improve the carbon tetrachloride conversion rate, service life and storage stability of the catalyst in the reaction of preparing 1,1,1,3,-tetrachloropropane from carbon tetrachloride and ethylene, and have unexpected technical effects.

[0107] (3) The P modification and core-shell structure of the present application are mutually synergistic, and the catalysts provided by the present application which are both P modified and form core-shell structure (Examples 1-3) can greatly improve the carbon tetrachloride conversion rate in the reaction of preparing 1,1,1,3,-tetrachloropropane from carbon tetrachloride and ethylene, and greatly improve the service life and storage stability of the catalyst, and have unexpected technical effects.

[0108] (4) Compared with using other phosphorus sources (such as triethyl phosphate or tributyl phosphate), the catalysts prepared by the present application using trimethyl phosphate as the phosphorus source (Examples 1-3) can greatly improve the carbon tetrachloride conversion rate and 1,1,1,3,-tetrachloropropane selectivity in the reaction of preparing 1,1,1,3,-tetrachloropropane from carbon tetrachloride and ethylene, and greatly improve the service life and storage stability of the catalyst, and have unexpected technical effects.

[0109] (5) Compared with using other organic ligands (such as trimesic acid or 2-amino terephthalic acid), the catalysts prepared by the present application using terephthalic acid as the organic ligand (Examples 1-3) can greatly improve the carbon tetrachloride conversion rate and 1,1,1,3,-tetrachloropropane selectivity in the reaction of preparing 1,1,1,3,-tetrachloropropane from carbon tetrachloride and ethylene, and greatly improve the service life and storage stability of the catalyst, and have unexpected technical effects.

[0110] (6) Compared with other pore-forming agents (such as benzoic acid or oxalic acid), the use of formic acid as a pore-forming agent in the preparation of the catalyst provided by the present application can greatly improve the carbon tetrachloride conversion rate and 1,1,1,3,-tetra-chloropropane selectivity in the reaction of the catalyst (Examples 1-3) catalyzing the preparation of 1,1,1,3,-tetra-chloropropane from carbon tetrachloride and ethylene, and greatly improve the service life and storage stability of the obtained catalyst, having unexpected technical effects.

[0111] (7) Compared with other noble metal salts (such as platinum nitrate or rhodium nitrate), the use of palladium nitrate as a noble metal salt in the preparation of the catalyst (Examples 1-3) provided by the present application can greatly improve the 1,1,1,3,-tetra-chloropropane selectivity in the reaction of the catalyst catalyzing the preparation of 1,1,1,3,-tetra-chloropropane from carbon tetrachloride and ethylene, and greatly improve the service life and storage stability of the obtained catalyst, having unexpected technical effects.

[0112] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, different embodiments or examples described in the present specification and the features of different embodiments or examples can be combined and modified by those skilled in the art without contradiction.

[0113] Although the embodiments of the present application have been shown and described above, it should be understood that the above-described embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A method for producing a catalyst, characterized by, The method comprises the following steps: S1: Fe-MOF precursor preparation: dissolving iron source in water to obtain an iron source solution; dissolving phosphorus source, organic ligand and pore-forming agent in organic solvent to obtain solution A; adding the iron source solution into solution A, heating and reacting, washing, centrifuging or filtering, obtaining solid, drying the solid to obtain Fe-MOF precursor; S2: preparation of P-modified Fe@ZSM core-shell structure catalyst: dispersing the Fe-MOF precursor obtained in step S1 in water, stirring and adding surfactant, aluminum source and palladium source to obtain solution B; dissolving silicon source in ammonia-containing aqueous solution to obtain silicon source solution; adding the silicon source solution into solution B, adjusting pH, stirring, precipitating solid, washing, drying, calcining, cooling to room temperature, and then reducing in a hydrogen atmosphere to obtain the P-modified Fe@ZSM core-shell structure catalyst, which is the catalyst.

2. The preparation method according to claim 1, wherein the iron source comprises at least one of ferric chloride or its hydrate, ferric nitrate or its hydrate, ferric sulfate or its hydrate, and ferric citrate; and / or the iron source comprises at least one of ferric chloride hexahydrate, ferric nitrate heptahydrate, ferric sulfate nonahydrate, and ferric citrate; and / or the phosphorus source comprises at least one of phosphoric acid, trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, triethyl phosphite, and triphenyl phosphine, preferably trimethyl phosphate; and / or the organic ligand comprises at least one of terephthalic acid, trimesic acid, trimellitic acid, and 2-hydroxyterephthalic acid, preferably terephthalic acid; and / or the pore-forming agent comprises at least one of benzoic acid, formic acid, oxalic acid, sodium formate, and sodium acetate, preferably formic acid; and / or the organic solvent comprises at least one of N,N-dimethylformamide, ethanol, and methanol.

3. The preparation method according to claim 2, wherein the concentration of the iron source in the iron source solution is 1.25 mol / L-2.50 mol / L; and / or corresponding to 1.25 mmol-5.00 mmol or 1.25 mmol-3.75 mmol of the phosphorus source per 100 mL of the organic solvent; and / or the molar ratio of the iron source to the organic ligand is 1:2-2:1; and / or the molar ratio of the organic ligand to the pore-forming agent is 1:5-5:1 or 1:2.5-2.5:1; and / or the molar ratio of the iron source to the phosphorus source is 1000:1-100:3 or 100:1-100:3; and / or the reaction temperature of the heating and reacting is 80℃-150℃, preferably 120℃-150℃ or 130℃-150℃; and / or the heating and reacting comprises microwave-assisted solvothermal reaction; and / or the reaction time of the heating and reacting is 0.5h-24h or 10h-24h or 12h-20h; and / or the washing in step S1 comprises washing with ethanol and water respectively; and / or the washing in step S1 comprises washing with ethanol and water for 1-5 times respectively.

4. The preparation method according to any one of claims 1-3, wherein the surfactant comprises at least one of ammonium lauryl sulfate or sodium cetyl sulfonate; and / or the aluminum source comprises at least one of aluminum chloride or a hydrate thereof, aluminum sulfate or a hydrate thereof, aluminum ammonium sulfate or a hydrate thereof; and / or the aluminum chloride or a hydrate thereof comprises aluminum chloride or aluminum chloride hexahydrate; and / or the silicon source comprises at least one of a metal salt of metasilicic acid, silicon dioxide, a metal salt of fluorosilicic acid, a metal salt of orthosilicic acid, a metal salt of silicic acid, a metal salt of orthodisilicic acid, a metal salt of disilicic acid, a metal salt of trisilicic acid; and / or the metal salt of metasilicic acid comprises sodium metasilicate; and / or the palladium source comprises at least one of palladium chloride or a hydrate thereof, palladium nitrate or a hydrate thereof, preferably at least one of palladium chloride or a hydrate thereof, palladium nitrate or a hydrate thereof.

5. The preparation method according to any one of claims 1-4, wherein the mass ratio of Pd element in the palladium source to Fe element in the iron source is 0.005:1-0.05:1 or 0.01:1-0.05:1; and / or the feeding molar ratio of the silicon source to the surfactant is 10000:1-500:1 or 3000:1-1000:1 or 2000:1; and / or the feeding molar ratio of Si atom in the silicon source to Al atom in the aluminum source is (5-100):1 or 15:1-20:1 or 19:1; and / or the concentration of ammonia in the aqueous ammonia solution is 25wt%-28wt%; and / or the pH adjustment is adjusting the pH to 8-9.

6. The method of making according to any one of claims 1-5, said calcining comprising: the calcination is performed in an air atmosphere.

7. The preparation method according to claim 6, wherein the calcination temperature of the calcination in the air atmosphere is 450°C-700°C; and / or the calcination time of the calcination in the air atmosphere is 3h-5h; and / or the heating rate of the calcination in the air atmosphere is 1°C / min-5°C / min; and / or the temperature of the heating reduction in the hydrogen atmosphere is 300°C-500°C; and / or the heating reduction time of the heating reduction in the hydrogen atmosphere is 0.5h-2h; and / or the heating rate of the heating reduction in the hydrogen atmosphere is 1°C / min-5°C / min.

8. A catalyst prepared according to any one of the preparation methods of claims 1-7.

9. Use of the catalyst prepared according to any one of the preparation methods of claims 1-7 or the catalyst of claim 8 in catalyzing the reaction of carbon tetrachloride and ethylene to prepare 1,1,1,3-tetrachloropropane.

10. A method for the synthesis of 1,1,1,3-tetrachloropropane, characterized in that comprising: carbon tetrachloride and ethylene are allowed to react in the presence of the catalyst of claim 8 to obtain 1,1,1,3-tetrachloropropane; optionally, the reaction temperature of the reaction is 80°C-130°C or 100°C-130°C; optionally, the reaction is performed under the condition that the ethylene gas pressure is 0.5MPa-1.5MPa, preferably under the condition that the ethylene gas pressure is 0.8MPa-1.1MPa.

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