Method for catalytically synthesizing phenyl chlorosilane through ZnCo-ZIF / CeO2 and catalyst used in method

Abstract

The invention belongs to the field of chemical engineering, and particularly provides a method for synthesizing phenyl chlorosilane through catalysis of ZnCo-ZIF / CeO2 and a catalyst used in the method, and the method comprises the following steps: using Ce (NO3) 3.6 H2O and urea to synthesize nano CeO2 through a hydrothermal method, and using Co (NO3) 2.6 H2O, Zn (NO3) 2.6 H2O, CeO2 and 2-methylimidazole to prepare ZnCo-ZIF / CeO2. The invention also provides a method for preparing phenyl chlorosilane by using the ZnCo-ZIF / CeO2 catalyst, which comprises the following steps of: adding the catalyst into a fixed bed reaction furnace, and reforming and synthesizing phenyl chlorosilane in the fixed bed reaction furnace by taking chlorosilane and chlorobenzene as raw materials. The method has the characteristics of low reaction temperature, good selectivity and the like.

Description

Technical Field

[0001] The invention belongs to the field of chemical industry, relates to the preparation of catalytic materials and phenylchlorosilane, and specifically relates to the application of a ZnCo-ZIF / CeO2 catalyst in the preparation of phenylchlorosilane. Background Art

[0002] With the continuous development of the chemical industry, silane compounds have gradually become one of the important raw materials in the building materials, electronics, automobile and cosmetics industries. As silane compounds, phenylsilane and diphenylsilane are important raw materials for synthesizing a variety of coupling agents or crosslinking agents, and are particularly suitable for the manufacture of high-performance silicone rubber, silicone oil, silicone resin and other products. Introducing phenyl chains into the above-mentioned silicone polymer molecules can effectively improve the heat resistance, chemical stability, radiation resistance and refractive index of the products.

[0003] Commonly used phenylchlorosilanes include phenyltrichlorosilane, methylphenyldichlorosilane, and diphenyldichlorosilane. At present, the preparation of phenylsilane and diphenylsilane mainly adopts liquid phase condensation method, Grignard method, cracking method, acid binding method, disproportionation method, thermal condensation method, sodium condensation method, direct synthesis method, etc.

[0004] The liquid phase condensation method is to irradiate the raw materials involved in the reaction with light of a certain wavelength (such as ultraviolet light), and then a photo-induced free radical reaction occurs to generate phenylchlorosilane. The Jilin Chemical Research Institute has achieved a yield of more than 54% and a selectivity of 62% in the synthesis of methylphenyldichlorosilane using methyldichlorosilane, benzene and chlorine as raw materials (Research on the synthesis of methylphenyldichlorosilane by light irradiation [J]. Synthetic Rubber Industry, 1980 (3): 188-191). Xiao Lin et al. synthesized methylphenyldiethoxysilane using magnesium, methyltriethoxysilane and chlorobenzene as raw materials, with a yield of 60.1%. (Synthesis process and optimization of methylphenyldiethoxysilane [J]. Journal of Nanchang University, 2009, 31(3): 227-229.) Patent CN101195633A discloses that a mixture of trimethyltrichlorodisilane and dimethyltetrachlorodisilane is subjected to a cracking reaction with halobenzene under the catalysis of the eighth subgroup and its complex, and the yield of the product methylphenyldichlorosilane is as high as 80%, but the catalyst is expensive and difficult to recover. Patent CN1807432A discloses that alkylimidazole is used as an acid binding agent to promote the reaction of methylhydrogendichlorosilane and chlorobenzene, and the reaction is cooled and settled after completion to separate alkylimidazole hydrochloride from methylphenyldichlorosilane, with a yield of up to 84.2%, but the reaction time of this method is relatively long and the product composition is complex.

[0005] Patent CN101628917A uses chlorobenzene and methyldichlorosilane as raw materials, chloroform, dichloromethane or carbon tetrachloride as catalyst, and prepares methylphenyldichlorosilane in a homemade reactor under the conditions of 0.2-0.8 MPa and 350-600° C. This method has the following disadvantages, such as high temperature and high pressure reaction conditions, the maximum yield is 52.7%, and the reaction efficiency is not high.

[0006] The process of synthesizing phenylsilane in a fixed bed was studied by using the gas phase condensation method. If we can find a catalyst with excellent performance to reduce the reaction energy barrier and achieve efficient and green synthesis, it will be of great significance to the research and development of large-scale production technology of phenylchlorosilane. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a method for synthesizing phenylchlorosilane catalyzed by ZnCo-ZIF / CeO2 and the catalyst used.

[0008] In order to solve the above technical problems, the present invention provides a method for preparing a nano CeO2-loaded ZnCo-ZIF bimetallic material catalyst, comprising the following steps:

[0009] 1.1) Preparation of nano-CeO2 (synthesized by hydrothermal method): prepared by using Ce(NO3)3·6H2O and urea;

[0010] 1.2) Preparation of ZnCo-ZIF / CeO2: prepared using Co(NO3)2·6H2O, Zn(NO3)2·6H2O, CeO2 and 2-methylimidazole.

[0011] As an improvement of the preparation method of the nano CeO2 loaded ZnCo-ZIF bimetallic material catalyst of the present invention:

[0012] 1.1) Preparation of Nano-CeO2:

[0013] Ce(NO3)3·6H2O and urea were added to deionized water and stirred to form a homogeneous mixture, with a molar ratio of Ce(NO3)3·6H2O:urea = 1:(1.5±0.1);

[0014] Then, the homogeneous mixed solution is transferred into a hydrothermal kettle and hydrothermally treated at 120-160°C (preferably 150-160°C) for 5±0.5h; then centrifuged (centrifuged at 10000±1000rpm for 10±2min), the solid obtained by centrifugation is washed and dried, and then calcined at 600±50°C for 5±0.5h to obtain nano-CeO2 (light yellow nano-CeO2);

[0015] Note: Calcination can be carried out in a muffle furnace;

[0016] 1.2) Preparation of ZnCo-ZIF / CeO2

[0017] The molar ratio n(Co(NO3)2·6H2O):n(Zn(NO3)2·6H2O):n(CeO2):n(2-methylimidazole)=1-3:2-5:10:10;

[0018] CeO2 powder was dispersed in anhydrous methanol, and then Zn(NO3)2·6H2O and Co(NO3)2·6H2O were added for ultrasonic dispersion, which was recorded as dispersion A;

[0019] Dissolve 2-methylimidazole in anhydrous methanol, referred to as solution B;

[0020] Then, solution B was added to dispersion A and stirring was continued for 6 to 12 hours, followed by centrifugation (at 10000±1000 rpm for 10±2 min), and the solid obtained by centrifugation was washed and dried to obtain a ZnCo-ZIF / CeO2 catalyst.

[0021] As a further improvement of the preparation method of the nano-CeO2-loaded ZnCo-ZIF bimetallic material catalyst of the present invention, in the step 1.1):

[0022] For every 10 mmol of Ce(NO3)3·6H2O, use 100±20 ml of deionized water;

[0023] Stir at room temperature for 1.5 to 2.5 hours to form a homogeneous mixed solution;

[0024] The solid obtained by centrifugation was washed with ethanol and pure water respectively, and then vacuum dried at 70±10℃ for 10-14h, and then heated at 4-6℃·min -1 The temperature is raised to 600±50℃ and calcined for 5±0.5h.

[0025] As a further improvement of the preparation method of the nano CeO2-loaded ZnCo-ZIF bimetallic material catalyst of the present invention, in step 1.2):

[0026] For every 6.0mmol CeO2, use 20±5ml of anhydrous methanol;

[0027] For every 6.0mmol of 2-methylimidazole, use 20±5ml of anhydrous methanol;

[0028] The solid obtained by centrifugation was washed with ethanol and pure water respectively, and vacuum dried at 70±10° C. for 10 to 14 h to obtain a ZnCo-ZIF / CeO 2 catalyst.

[0029] As a further improvement of the preparation method of the nano CeO2-loaded ZnCo-ZIF bimetallic material catalyst of the present invention,

[0030] In step 1.1), the hydrothermal treatment temperature is 160°C;

[0031] In step 1.2), n(Co(NO3)2·6H2O):n(Zn(NO3)2·6H2O):n(CeO2):n(2-methylimidazole)=1:2~5:10:10; stirring time is 8~12h (more preferably 10h).

[0032] The present invention also provides a method for preparing phenylchlorosilane using the ZnCo-ZIF / CeO2 catalyst obtained by any of the above methods:

[0033] A catalyst (ZnCo-ZIF / CeO2 catalyst) is added to a fixed bed reactor, and then an inert gas (such as nitrogen) is introduced to purge the reaction device;

[0034] Then, the chlorosilane and chlorobenzene as raw materials are preheated and vaporized to obtain vaporized products, and the feed ratio V 含氯硅烷 :V 氯苯 =1:1.2~1.7; then the vapor is passed into a fixed bed reactor filled with catalyst, with a volume space velocity of 300~500h -1 (Preferably 350-425h -1 ), the reaction pressure is 0.1-1.0Mpa (0.4-0.7Mpa), and the reaction temperature is 200°C-350°C (preferably 250-300°C);

[0035] Volumetric space velocity = volume flow rate of raw material after gasification (L / h) / catalyst loading volume (L);

[0036] The reaction product is condensed (condensed to below 25°C) after exiting the fixed bed reactor, and then subjected to gas-liquid separation to obtain phenylchlorosilane as a product. That is, the condensate enters a gas-liquid separator to separate the product and hydrogen chloride gas.

[0037] As an improvement of the method for preparing phenylchlorosilane of the present invention:

[0038] The chlorosilane is any of the following: trichlorosilane, phenylchlorosilane, phenyldichlorosilane, methyldichlorosilane, dimethyldichlorosilane, triethylchlorosilane, ethyltrichlorosilane, diethyldichlorosilane, methylvinylchlorosilane, vinyltrichlorosilane.

[0039] As an improvement of the method for preparing phenylchlorosilane of the present invention: the liquid feed rate is 0.003 to 0.005 L / h.

[0040] The fixed bed reactor used in the present invention has a furnace length of 800 mm, an outer diameter of 30 mm, and an inner diameter of 25 mm. A catalyst is added into the fixed bed reactor, and the catalyst loading amount is 15 to 20 g.

[0041] The reaction formula is as follows:

[0042]

[0043] The present invention firstly prepares a CeO2-loaded ZnCo-ZIF alloy catalyst, uses chlorosilane and chlorobenzene as raw materials, and recombines them in a fixed bed reactor to synthesize phenylchlorosilane (phenylsilane or diphenylsilane, etc.). The process has the characteristics of low reaction temperature and good selectivity.

[0044] The present invention loads ZnCo-ZIF on the surface of nano CeO2, and successfully prepares ZnCo-ZIF / CeO2 bimetallic catalyst, which is used for catalyzing the recombination of chlorosilane and chlorobenzene into phenylsilane or diphenylsilane. ZnCo-ZIF / CeO2 has high specific surface area, pore volume and abundant acid-base sites, and has high adsorption capacity for chlorobenzene, which is conducive to the catalyst adsorption reaction raw materials. In addition, there is a strong interaction between the nano CeO2 carrier and the metal component, which helps to stabilize the metal particles and prevents the sintering or agglomeration of the metal particles during the reaction. The method for preparing phenylchlorosilane of the present invention is suitable for continuous production, and the production capacity is greatly improved. In addition, the present invention reduces the reaction temperature of chlorosilane and chlorobenzene recombination into phenylsilane or diphenylsilane, the prepared catalyst has a long service life, high reaction selectivity, high raw material conversion rate, and reduces production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings.

[0046] Figure 1 This is a schematic diagram of a fixed bed continuous production device. DETAILED DESCRIPTION

[0047] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto:

[0048] Device Example 1: A fixed bed continuous production device for synthesizing phenylchlorosilane, such as Figure 1 As shown;

[0049] It includes an N2 cylinder 1 for providing N2, a raw material tank Ⅰ2 for providing chlorosilane, a raw material tank Ⅱ3 for providing chlorobenzene, a preheating vaporization chamber 19, a fixed bed reaction furnace 22, a condensing tank 24, a low-temperature circulation tank 25, a gas-liquid separation tank 29 and a washing tank 34.

[0050] The cylinder 1 is connected to the inlet of the mixer 17 through the ball valve III 4, the rotor flow meter I 5, and the check valve III 6 in sequence;

[0051] The raw material tank Ⅰ2 is connected to the inlet of the mixer 17 through the ball valve Ⅰ7, the metering pump Ⅰ8 and the check valve Ⅰ11 in sequence; the metering pump Ⅰ8 is equipped with a flow display controller Ⅰ10; a pressure gauge Ⅰ9 is arranged between the metering pump Ⅰ8 and the check valve Ⅰ11;

[0052] The raw material tank Ⅱ3 is connected to the inlet of the mixer 17 through the ball valve Ⅱ12, the metering pump Ⅱ13 and the check valve Ⅱ16 in sequence. The metering pump Ⅱ13 is equipped with a flow display controller Ⅱ15, and a pressure gauge Ⅱ14 is arranged between the metering pump Ⅱ13 and the check valve Ⅱ16;

[0053] That is, each of the metering pump I8 and the metering pump II13 is provided with a flow rate display controller after the pump.

[0054] The outlet of the mixer 17 is connected to the inlet of the preheating vaporization chamber 19, and the outlet of the preheating vaporization chamber 19 is connected to the top of the fixed bed reactor 22 through a pipeline provided with a heating belt 20. The preheating vaporization chamber 19 is equipped with a temperature controller 18. A thermocouple 23 for temperature measurement is provided in the fixed bed reactor 22; a pressure gauge 21 is provided at the top of the fixed bed reactor 22.

[0055] The condensation tank 24 is provided with a low-temperature circulation tank 25 , and a flow regulating valve 26 is provided on the pipeline connecting the low-temperature circulation tank 25 and the condensation tank 24 .

[0056] The bottom outlet of the fixed bed reactor 22 is connected to the inlet of the condensation tank 24, and the outlet of the condensation tank 24 is connected to the inlet of the gas-liquid separation tank 29 through a pipeline provided with a ball valve 28; the bottom outlet (liquid phase outlet) of the gas-liquid separation tank 29 is provided with a ball valve 30 and a stop valve 31; the top outlet (gas phase outlet) of the gas-liquid separation tank 29 is divided into two paths, one of which is connected to the air receiving bag after passing through the stop valve 32, and the other is connected to the inlet of the water washing tank 34 through the stop valve 33 to absorb the hydrogen chloride in the tail gas, and the outlet of the washing tank 34 is the environment (VENT).

[0057] The fixed bed reactor 22 is a 316L stainless steel pipe with a furnace length of 800 mm, an outer diameter of 30 mm, an inner diameter of 25 mm, and a constant temperature zone length of about 50 mm.

[0058] Embodiment 1, a kind of method of using trichlorosilane and chlorobenzene to prepare phenyltrichlorosilane, carries out the following steps in sequence:

[0059] 1. Preparation of ZnCo-ZIF / CeO2 catalyst:

[0060] 1.1) Preparation of Nano-CeO2

[0061] CeO2 was synthesized by a hydrothermal method, i.e., 4.34 g (10.0 mmol) of Ce(NO3)3·6H2O and 0.90 g (15.0 mmol) of urea were dissolved in 100 ml of deionized water and stirred at room temperature for 2 h to form a homogeneous mixture; the homogeneous mixture was then transferred to a hydrothermal reactor and hydrothermally treated at 160°C for 5 h; then a centrifuge was used to centrifuge at 10,000 rpm for 10 min, and finally the solid obtained by centrifugation was washed 3 times with ethanol and pure water respectively to remove residual raw materials, and vacuum dried at 70°C overnight (about 12 h) to obtain a white powder, which was then precipitated at 4 to 6°C·min -1 The temperature was raised to 600 °C and calcined for 5 h to obtain light yellow CeO2 powder.

[0062] The light yellow CeO2 powder was tested by specific surface area, and the average particle size was about 10 nm; therefore, it was nano CeO2.

[0063] 1.2) Preparation of ZnCo-ZIF / CeO2

[0064] 1.03 g (6.0 mmol) of CeO2 powder was dispersed in 20 ml of anhydrous methanol, followed by the addition of 0.36 g (1.2 mmol) of Zn(NO3)2·6H2O and 0.17 g (0.6 mmol) of Co(NO3)2·6H2O, and ultrasonic dispersion was performed, which was recorded as dispersion A.

[0065] Separately, 0.58 g (6.0 mmol) of 2-methylimidazole was dissolved in 20 ml of anhydrous methanol, referred to as solution B;

[0066] Then, liquid B was added to liquid A and stirring was continued for 6 hours. Then, a centrifuge was used to centrifuge at 10,000 rpm for 10 minutes. Finally, the collected solid was washed three times with ethanol and pure water respectively, and vacuum dried at 70°C overnight to obtain a ZnCo-ZIF / CeO2 catalyst.

[0067] That is, in this Example 1, n(Co(NO3)2·6H2O):n(Zn(NO3)2·6H2O):n(CeO2):n(2-methylimidazole)=1:2:10:10.

[0068] 2. Catalyst loading

[0069] Take 20 g of the catalyst obtained in step 1.2) and place it in the constant temperature zone of the fixed bed reactor 22. Open the ball valve III4 and introduce N2 provided by the N2 cylinder 1 at a flow rate of 0.005 L / h. Figure 1 In the device, impurities in the device are evacuated; nitrogen mixed with air is finally discharged from the outlet of the washing tank 34, and the nitrogen passing time is 10 minutes.

[0070] Then close ball valve III4 and proceed to step 3 below.

[0071] 3. Feeding and discharging

[0072] The reaction pressure in the fixed bed reactor 22 is controlled to be stable at 0.4 MPa, and the temperature of the preheating vaporization chamber 19 is maintained at 240°C and the temperature of the fixed bed reactor 22 is maintained at 250°C by adjusting the heating power of the reactor jacket; the ball valve I7, the ball valve II12, the metering pump I8, and the metering pump II13 are opened, and then chlorobenzene is introduced at a rate of 0.005 L / h, and trichlorosilane is introduced at a rate of 0.003 L / h. The raw materials composed of chlorobenzene and trichlorosilane are mixed in the mixer 17 and uniformly enter the preheating vaporization chamber 19 for vaporization, and then react in the fixed bed reactor 22 under the action of the catalyst; the reaction pressure is 0.4 MPa, the reaction temperature is 250°C, and the raw material feed volume space velocity is 350 h -1 .

[0073] Note: Raw material feed volume space velocity = raw material gasification volume flow rate (L / h) / catalyst loading volume (L)

[0074] The reaction formula is

[0075] The reaction product is finally condensed in the condenser 24 and enters the gas-liquid separation tank 29. At this time, the phenyltrichlorosilane in the reaction product is condensed into liquid, while the hydrogen chloride in the reaction product is still gas. Therefore, phenyltrichlorosilane is discharged from the liquid phase outlet of the gas-liquid separation tank 29, and the hydrogen chloride is discharged from the gas phase outlet of the gas-liquid separation tank 29 and then absorbed in the water washing tank 34.

[0076] The liquid phase outlet of the gas-liquid separation tank 29 is connected to an online gas phase detection and evaluation device, and the product composition is detected every 5 minutes. After 30 minutes of reaction, the reaction is stable. After stabilization, every time the reaction is carried out for 1 minute, the amount of trichlorosilane used is 0.06710g, and 0.07367g of the target product phenyltrichlorosilane is obtained, so the yield is 70.3%.

[0077] Yield = n 苯基三氯硅烷 / n 三氯氢硅 ×100%.

[0078] Example 2-1: Compared with Example 1, the following changes are made: the hydrothermal temperature in the preparation of nano-CeO2 in step 1.1) is changed from 160°C to 120°C, and the rest is the same as Example 1.

[0079] The average particle size of the light yellow CeO2 powder was about 3 nm; the yield of phenyltrichlorosilane after stabilization was 64.7%.

[0080] Example 2-2: With respect to Example 1, the following changes are made: the hydrothermal temperature in the preparation of nano-CeO2 in step 1.1) is changed from 160°C to 140°C, and the rest is the same as Example 1.

[0081] The average particle size of the light yellow CeO2 powder was about 5 nm; the yield of phenyltrichlorosilane after stabilization was 67.2%.

[0082] Example 3-1: Compared with Example 1, the following changes are made:

[0083] Change the ratio of "n(Co(NO3)2·6H2O):n(Zn(NO3)2·6H2O):n(CeO2):n(2-methylimidazole)" in step 1) from 1:2:10:10 to 1:3:10:10;

[0084] That is, the amount of Co(NO3)2·6H2O used was 0.6 mmol, the amount of Zn(NO3)2·6H2O used was 1.8 mmol, the amount of CeO2 used was 6.0 mmol, and the amount of 2-methylimidazole used was 6.0 mmol.

[0085] The rest is the same as Example 1.

[0086] The yield of phenyltrichlorosilane after stabilization was 75.4%.

[0087] Embodiment 3-2, relative to embodiment 1, makes the following changes:

[0088] Change the ratio of "n(Co(NO3)2·6H2O):n(Zn(NO3)2·6H2O):n(CeO2):n(2-methylimidazole)" in step 1) from 1:2:10:10 to 1:5:10:10;

[0089] That is, the amount of Co(NO3)2·6H2O used was 0.6 mmol, the amount of Zn(NO3)2·6H2O used was 3.0 mmol, the amount of CeO2 used was 6.0 mmol, and the amount of 2-methylimidazole used was 6.0 mmol.

[0090] The rest is the same as Example 1.

[0091] The yield of phenyltrichlorosilane after stabilization was 80.6%.

[0092] Embodiment 3-3, relative to embodiment 1, makes the following changes:

[0093] Change the ratio of "n(Co(NO3)2·6H2O):n(Zn(NO3)2·6H2O):n(CeO2):n(2-methylimidazole)" in step 1) from 1:2:10:10 to 3:5:10:10;

[0094] That is, the amount of Co(NO3)2·6H2O used was 1.8 mmol, the amount of Zn(NO3)2·6H2O used was 3.0 mmol, the amount of CeO2 used was 6.0 mmol, and the amount of 2-methylimidazole used was 6.0 mmol.

[0095] The rest is the same as Example 1.

[0096] The yield of phenyltrichlorosilane after stabilization was 76.5%.

[0097] Example 4-1: Compared with Example 1, the following changes are made:

[0098] The stirring time in step 1.2) was changed from 6 h to 8 h, which was equivalent to Example 1.

[0099] The yield of phenyltrichlorosilane after stabilization was 85.3%.

[0100] Embodiment 4-2, relative to embodiment 1, makes the following changes:

[0101] The stirring time in step 1.2) was changed from 6 h to 10 h, which was equivalent to Example 1.

[0102] The yield of phenyltrichlorosilane after stabilization was 89.7%.

[0103] Embodiment 4-3, relative to embodiment 1, makes the following changes:

[0104] The stirring time in step 1.2) was changed from 6 h to 12 h, which was equivalent to Example 1.

[0105] The yield of phenyltrichlorosilane after stabilization was 87.6%.

[0106] Example 5-1, a method for preparing phenylmethyldichlorosilane using methyldichlorosilane and chlorobenzene;

[0107] Step 1 and step 2 are equivalent to Example 4-2.

[0108] 3. Feeding and discharging

[0109] The reaction pressure in the fixed bed reactor 22 is controlled to be stable at 0.6 MPa.

[0110] Maintain the temperature of the preheating vaporization chamber 19 at 240°C and the temperature of the fixed bed reaction furnace 22 at 250°C;

[0111] Chlorobenzene was introduced at a rate of 0.005 L / h, and methyldichlorosilane was introduced at a rate of 0.003 L / h.

[0112] The raw material feed volume space velocity is 350h -1 ,

[0113] The reaction formula is

[0114] The rest is as per step 3 of Example 1.

[0115] The product composition was detected every 5 minutes in an online gas phase detection and evaluation device. After 30 minutes of reaction, the reaction was stable. After stabilization, the amount of methyldichlorosilane was 0.05525 g for each 1 minute of reaction, and 0.06187 g of the target product phenylmethyldichlorosilane was obtained, so the yield was 67.4%.

[0116] Example 5-2: A method for preparing phenyldimethylchlorosilane using dimethylchlorosilane and chlorobenzene

[0117] Step 1 and step 2 are equivalent to Example 4-2.

[0118] 3. Feeding and discharging

[0119] The reaction pressure in the fixed bed reactor 22 is controlled to be stable at 0.6 MPa.

[0120] Maintain the temperature of the preheating vaporization chamber 19 at 290°C and the temperature of the fixed bed reaction furnace 22 at 300°C;

[0121] Chlorobenzene was introduced at a rate of 0.005 L / h, and dimethylchlorosilane was introduced at a rate of 0.004 L / h.

[0122] The raw material feed volume space velocity is 425h -1 ,

[0123] The reaction formula is

[0124] The rest is as per step 3 of Example 1.

[0125] The product composition was detected every 5 minutes in an online gas phase detection and evaluation device. After 30 minutes of reaction, the reaction was stable. After stabilization, the amount of dimethylchlorosilane used was 0.05708 g for each 1 minute of reaction, and 0.07374 g of the target product phenyldimethylchlorosilane was obtained, so the yield was 71.6%.

[0126] Example 5-3, a method for preparing diphenyldichlorosilane using dihydrogen dichlorosilane and chlorobenzene;

[0127] Step 1 and step 2 are equivalent to Example 4-2.

[0128] 3. Feeding and discharging

[0129] The reaction pressure in the fixed bed reactor 22 is controlled to be stable at 0.7 MPa.

[0130] Maintain the temperature of the preheating vaporization chamber 19 at 290°C and the temperature of the fixed bed reaction furnace 22 at 300°C;

[0131] Chlorobenzene was introduced at a rate of 0.005 L / h, and dichlorosilane was introduced at a rate of 0.003 L / h;

[0132] The raw material feed volume space velocity is 375h -1

[0133] The reaction formula is

[0134] The rest is as per step 3 of Example 1.

[0135] The product composition was detected every 5 minutes in an online gas phase detection and evaluation device. After 30 minutes of reaction, the reaction was stable. After stabilization, every time the reaction was carried out for 1 minute, the amount of dichlorosilane was 0.06250 g, and 0.09929 g of the target product diphenyldichlorosilane was obtained, so the yield was 58.9%.

[0136] Experiment 1: Stability

[0137] Example 4-2 was repeated. After the prepared ZnCo-ZIF / CeO2 catalyst was used continuously for 48 hours, the yield of phenyltrichlorosilane was still 86.9%, so the catalyst had a long service life.

[0138] Comparative Example 1: Compared with Example 4-2, the following changes were made:

[0139] Cancel "1.1), preparation of nano-CeO2", that is, directly use commercially available CeO2 in step 1.2); the rest is the same as Example 4-2.

[0140] The yield of phenyltrichlorosilane after stabilization was only 58.6%, and the stability test results showed that it could only be maintained for 3 hours.

[0141] Comparative Example 2: Compared with Example 1, the following changes were made:

[0142] The stirring time in step 1.2) was changed from 6 h to 3 h, which was equivalent to Example 1.

[0143] The yield of phenyltrichlorosilane after stabilization was 64.8%.

[0144] Comparative Example 3: Compared with Example 4-2, the following changes were made:

[0145] The addition of Co(NO3)2·6H2O in "1.2), Preparation of ZnCo-ZIF / CeO2" is cancelled, and the obtained catalyst is Zn-ZIF / CeO2, and the rest is the same as Example 4-2. The yield of phenyltrichlorosilane after stabilization is only 35.7%.

[0146] Comparative Example 4: Compared with Example 1, the following changes were made:

[0147] The reaction pressure in step 3 was changed from 0.4 MPa to 0.1 MPa, which is equivalent to Example 1.

[0148] The yield of phenyltrichlorosilane after stabilization was 52.2%.

[0149] Finally, it should be noted that the above examples are only some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and there are many variations. All variations that can be directly derived or associated with the content disclosed by a person skilled in the art should be considered as the protection scope of the present invention.

Claims

1. A method for preparing a nano-CeO2-loaded ZnCo-ZIF bimetallic material catalyst, characterized in that The following steps are involved: 1.1) Preparation of nano-CeO2: using Ce(NO3)3·6H2O and urea; 1.2) Preparation of ZnCo-ZIF / CeO2: prepared using Co(NO3)2·6H2O, Zn(NO3)2·6H2O, CeO2 and 2-methylimidazole.

2. The method for preparing a nano-CeO2-loaded ZnCo-ZIF bimetallic catalyst according to claim 1, characterized in that: 1.1) Preparation of Nano-CeO2: Ce(NO3)3·6H2O and urea were added to deionized water and stirred to form a homogeneous mixture, with a molar ratio of Ce(NO3)3·6H2O:urea = 1:(1.5±0.1); Then, the homogeneous mixed solution is transferred into a hydrothermal reactor and hydrothermally treated at 120-160°C for 5±0.5h; then centrifuged, the solid obtained by centrifugation is washed and dried, and then calcined at 600±50°C for 5±0.5h to obtain nano-CeO2; 1.2) Preparation of ZnCo-ZIF / CeO2 The molar ratio n(Co(NO3)2·6H2O):n(Zn(NO3)2·6H2O):n(CeO2):n(2-methylimidazole)=1-3:2-5:10:10; CeO2 powder was dispersed in anhydrous methanol, and then Zn(NO3)2·6H2O and Co(NO3)2·6H2O were added for ultrasonic dispersion, which was recorded as dispersion A; Dissolve 2-methylimidazole in anhydrous methanol, referred to as solution B; Then, solution B was added to dispersion A and stirring was continued for 6 to 12 hours, followed by centrifugation (centrifugation at 10000 rpm for 10 minutes), and the solid obtained by centrifugation was washed and dried to obtain a ZnCo-ZIF / CeO2 catalyst.

3. The preparation method of nano-CeO2 loaded ZnCo-ZIF bimetallic catalyst according to claim 2, characterized in that In the step 1.1): For every 10 mmol of Ce(NO3)3·6H2O, use 100±20 ml of deionized water; Stir at room temperature for 1.5 to 2.5 hours to form a homogeneous mixed solution; The solid obtained by centrifugation was washed with ethanol and pure water respectively, and then vacuum dried at 70±10℃ for 10-14h, and then heated at 4-6℃·min -1 The temperature is raised to 600±50℃ and calcined for 5±0.5h.

4. The preparation method of nano-CeO2-loaded ZnCo-ZIF bimetallic catalyst according to claim 3, characterized in that In step 1.2): For every 6.0mmol CeO2, use 20±5ml of anhydrous methanol; For every 6.0mmol of 2-methylimidazole, use 20±5ml of anhydrous methanol; The solid obtained by centrifugation was washed with ethanol and pure water respectively, and vacuum dried at 70±10° C. for 10 to 14 h to obtain a ZnCo-ZIF / CeO 2 catalyst.

5. The method for preparing the nano-CeO2-loaded ZnCo-ZIF bimetallic catalyst according to any one of claims 1 to 4, characterized in that: In step 1.1), the hydrothermal treatment temperature is 160°C; In step 1.2), n(Co(NO3)2·6H2O):n(Zn(NO3)2·6H2O):n(CeO2):n(2-methylimidazole)=1:2~5:10:10; stirring time is 8~12h.

6. A method for preparing phenylchlorosilane using the ZnCo-ZIF / CeO2 catalyst obtained according to any one of claims 1 to 5, characterized in that: Adding catalyst into the fixed bed reactor, followed by purging with inert gas; Then, the chlorosilane and chlorobenzene as raw materials are preheated and vaporized to obtain vaporized products, and the feed ratio V 含氯硅烷 :V 氯苯 =1:1.2~1.7; then the vaporized product is passed into a fixed bed reactor filled with catalyst, with a volume space velocity of 300~500h -1 , the reaction pressure is 0.1~1.0Mpa, and the reaction temperature is 200℃~350℃; The reaction product is condensed after coming out of the fixed bed reactor, and then subjected to gas-liquid separation to obtain phenylchlorosilane as a product.

7. The method for preparing phenylchlorosilane according to claim 6, characterized in that: The chlorosilane is any of the following: trichlorosilane, phenylchlorosilane, phenyldichlorosilane, methyldichlorosilane, dimethyldichlorosilane, triethylchlorosilane, ethyltrichlorosilane, diethyldichlorosilane, methylvinylchlorosilane, vinyltrichlorosilane.

8. The method for preparing phenylchlorosilane according to claim 6 or 7, characterized in that: Liquid feed rate 0.003~0.005L / h.

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