A zinc-based catalyst for gas-solid phase acetylene hydration reaction and a preparation method thereof

Abstract

The application discloses a zinc-based catalyst for gas-solid phase acetylene hydration reaction and a preparation method thereof, relates to the technical field of catalyst preparation, and solves the problems of poor stability, active component loss and carbon deposition when the catalyst participates in acetylene hydration reaction to produce acetaldehyde, and the preparation comprises the following steps: step one: two clean 500ml beakers are prepared, and the two beakers are marked as No. 1 and No. 2; 200ml deionized water and a magnet are added into the two beakers respectively; a magnetic stirrer is opened; and a constant temperature system of the stirrer is adjusted to 20-40 DEG C, and the stirring rate is 500rpm; step two: under the condition that the temperature is kept at 20-40 DEG C and the stirring rate is kept at 500rpm, 1.35g zinc chloride is added into the No. 1 beaker. The catalyst prepared by the application has the characteristics of low price and high yield, and takes ZIF-8 with high porosity, adjustable crystal structure and good thermal stability as a precursor and sodium diethyldithiocarbamate trihydrate as a heteroatom dopant.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of catalyst preparation, in particular to a zinc-based catalyst for gas-solid phase acetylene hydration reaction and a preparation method thereof. BACKGROUND

[0002] The acetylene hydration reaction for preparing acetaldehyde is an important unit for producing acetaldehyde downstream products in China. Acetaldehyde can be used to produce acetic acid, pentaerythritol, ethyl acetate, pyridine compounds and crotonaldehyde, and has wide application in the fields of pesticides, medicines, feed and food additives. There are two ways to produce acetaldehyde, acetylene hydration and ethylene oxidation, but ethylene is mainly derived from the cracking of petroleum. According to the energy structure characteristics of China, which is rich in coal, poor in oil and short of gas, it is an inevitable trend to develop chemical products sourced from coal, which can effectively alleviate the dependence of current industrial production on the petroleum chemical industry and is an important cornerstone to ensure China's energy security. Therefore, it is particularly important to develop a simple and efficient catalyst for producing acetaldehyde.

[0003] At present, the catalyst is mainly used to participate in the acetylene hydration reaction to produce acetaldehyde. The acetylene conversion rate and acetaldehyde selectivity of the catalyst are crucial. In the early stage of synthesizing acetaldehyde by gas-solid phase acetylene hydration method, the catalyst mainly used is a catalyst with zeolite as the carrier.

[0004] However, this type of catalyst still has many shortcomings. After that, more and more researchers began to study from the aspects of carrier modification, transition metal doping, ligand modification, catalytic mechanism, etc. Although certain research results have been achieved, the catalyst stability, active component loss and carbon deposition are still key problems that need to be studied. Therefore, the existing demand is not met, and we propose a zinc-based catalyst for gas-solid phase acetylene hydration reaction and a preparation method thereof. SUMMARY

[0005] The purpose of the present application is to provide a zinc-based catalyst for gas-solid phase acetylene hydration reaction and a preparation method thereof, to solve the problems of the catalyst participating in the acetylene hydration reaction to produce acetaldehyde, which has many shortcomings, and more and more researchers begin to study from the aspects of carrier modification, transition metal doping, ligand modification, catalytic mechanism, etc. Although certain research results have been achieved, the catalyst stability, active component loss and carbon deposition are still problems that need to be studied.

[0006] To achieve the above purpose, the present application provides the following technical scheme: a zinc-based catalyst for gas-solid phase acetylene hydration reaction, the zinc-based catalyst comprising a zinc source, an organic ligand, a deprotonation agent and a sulfur source dopant.

[0007] The zinc source is zinc chloride.

[0008] The organic ligand is 2-methylimidazole;

[0009] The deprotonating agent is triethylamine;

[0010] The sulfur source dopant is sodium diethyldithiocarbamate trihydrate;

[0011] The zinc-based catalyst is derived from a metal-organic framework ZIF-8 precursor to form a carbon material by calcination.

[0012] A preparation method of a zinc-based catalyst for gas-solid phase acetylene hydration reaction, comprising the following steps:

[0013] Step one: prepare two clean 500ml beakers, and label them as No. 1 and No. 2, respectively, add 200ml of deionized water and a magnetic stirrer to each of them, turn on the magnetic stirrer, and adjust the constant temperature system of the stirrer to 20-40℃, with a stirring rate of 500rpm;

[0014] Step two: under the condition of keeping the temperature at 20-40℃ and the stirring rate at 500rpm, add 1.35g of zinc chloride to the No. 1 beaker, and continuously stir for 10min to form a uniform solution;

[0015] Step three: under the condition of keeping the temperature at 20-40℃ and the stirring rate at 500rpm, add 6.5g of 2-methylimidazole to the No. 2 beaker, and stir for 10min to make the 2-methylimidazole completely dissolved, then add 1g of sodium diethyldithiocarbamate trihydrate to the No. 2 beaker, and continuously stir for 10min to form a mixed uniform solution;

[0016] Step four: use a clean 25ml measuring cylinder to measure 15ml of triethylamine, and add it to the No. 2 beaker, and continuously stir for 10min to form a mixed uniform solution;

[0017] Step five: under the condition of keeping the temperature at 20-40℃ and the stirring rate of the stirrer holding the No. 2 beaker at 600rpm, quickly pour the solution in the No. 1 beaker into the No. 2 beaker, and stir for 2h to form a sulfur source modified ZIF-8, which is labeled as S-ZIF-8;

[0018] Step six: use an inner diameter of 8cm suction filter funnel to suction filter the product in the No. 2 beaker, and use 500ml of deionized water to wash the product during the suction filtering process;

[0019] Step seven: the funnel containing the washed product is moved into the constant temperature drying oven at 80°C for 10h, after cooling, the product is ground and put into a clean ceramic capsule, under argon atmosphere, the temperature is raised to T at a rate of 5°C / min and kept for 4h, after cooling, the catalyst is obtained, the catalyst is labeled as Zn-NSC-T, the catalyst activity test is carried out, and the sample is stored in the sample bag for standby after the test.

[0020] Preferably, the temperature T is 500°C, 600°C, 700°C or 800°C.

[0021] An application of a zinc-based catalyst for gas-solid phase acetylene hydration reaction, including catalyst activity test, the catalyst activity test includes the following steps:

[0022] S1: purging the catalyst with N2, the purpose is to remove impurity gas in the reaction device;

[0023] S2: carrying out acetylene hydration reaction in a continuous fixed bed flow microreactor at normal pressure, the inner diameter of the continuous fixed bed flow microreactor at normal pressure is 10mm, 2ml catalyst sample is put into the tubular reactor, and the tubular reactor is placed in the middle of the reactor furnace;

[0024] S3: heating, at the same time, setting the condensation circulating pump temperature to-2°C, when the reaction temperature reaches temperature S1 and the display temperature of the reaction water reaches temperature S2, the catalyst in the fixed bed reactor is activated by the peristaltic pump for 0.012g·min -1 , and the activation time is thirty minutes;

[0025] S4: turning off the N2 switch, after the nitrogen flow meter shows zero, opening C2H2, according to the reaction conditions of and n(H2O) / n(C2H2)=4, acetylene and water vapor are injected into the reactor;

[0026] S5: the content of the product is detected by manual injection of gas chromatography every hour.

[0027] Preferably, the main product of the acetylene hydration reaction is acetaldehyde, the by-products are acetone and butenal, and there is also unreacted acetylene.

[0028] Preferably, the conversion rate of acetylene and the selectivity of acetaldehyde are calculated according to the following formula:

[0029] X C2H2 =[(φ A0 -φ A ) / φ A0 ]×100%;

[0030] S CH3CHO =[φ AA / (f A0 - f A )]*100%;

[0031] Wherein, f A0 represents the volume fraction of C2H2 in raw materials, f A represents the volume fraction of residual C2H2 in products, f AA represents the volume fraction of CH3CHO in products after reaction.

[0032] Preferably, the temperature S1 is 260 DEG C.

[0033] Preferably, the temperature S2 is 170 DEG C.

[0034] Compared with the prior art, the beneficial effects of the present application are:

[0035] 1、The present application forms a carbon shell on the surface of the carbon material derived from the metal organic framework ZIF-8 precursor, effectively inhibits the loss of zinc, and to some extent improves the stability of the catalyst, adopts the carbon material derived from the metal organic framework, the active metal is uniformly dispersed, and the doping of sulfur atoms inhibits the generation of carbon deposition to some extent, and improves the stability of the catalyst.

[0036] 2、The present application makes the whole catalytic system more stable and has higher catalytic activity through the doping of sulfur atoms. The conversion rate of acetylene and the selectivity of acetaldehyde are obviously improved. As the rate control step of the reaction, the doping of sulfur atoms significantly reduces the energy barrier of acetylene activation in the acetylene hydration process, so that the reaction is easier to proceed.

[0037] 3、The Zn-NSC catalyst prepared by the present application has the characteristics of low price, high yield and the like, and the ZIF-8 precursor has high porosity, adjustable crystal structure and good thermal stability. Therefore, the present application is a new method for synthesizing efficient, stable, environmentally friendly and economical catalysts. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 It is a performance schematic diagram of the catalyst prepared by the present application for catalyzing acetylene hydration.

[0039] Figure 2 It is an XRD characterization schematic diagram of the catalyst prepared by the present application.

[0040] Figure 3 It is a TG characterization schematic diagram of the Zn-NSC-600 catalyst prepared by the present application.

[0041] Figure 4 It is an XPS characterization schematic diagram of the Zn-NSC-600 catalyst prepared by the present application.

[0042] Figure 5 XAFS characterization of Zn-NSC-600 catalyst prepared in the present application. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments.

[0044] Please refer to Figures 1 to 5 An embodiment provided by the present application is a zinc-based catalyst for gas-solid phase acetylene hydration reaction, the zinc-based catalyst comprising a zinc source, an organic ligand, a deprotonating agent, and a sulfur source dopant.

[0045] The zinc source is zinc chloride.

[0046] The organic ligand is 2-methyl imidazole.

[0047] The deprotonating agent is triethylamine.

[0048] The sulfur source dopant is diethyl dithiocarbamic acid sodium salt trihydrate.

[0049] A preparation method of a zinc-based catalyst for gas-solid phase acetylene hydration reaction, comprising the following steps:

[0050] Step one: prepare two clean 500ml beakers, and label them as No. 1 and No. 2, respectively, add 200ml deionized water and magnetic sub into each of the two beakers, open the magnetic stirrer, and adjust the constant temperature system of the stirrer to 20-40℃, and the stirring rate is 500rpm;

[0051] Step two: under the condition that the temperature is kept at 20-40℃ and the stirring rate is kept at 500rpm, add 1.35g zinc chloride into the No. 1 beaker, and continuously stir for 10min to form a uniform solution;

[0052] Step three: under the condition that the temperature is kept at 20-40℃ and the stirring rate is kept at 500rpm, add 6.5g of 2-methyl imidazole into the No. 2 beaker, and stir for 10min to make the 2-methyl imidazole completely dissolved, then add 1g diethyl dithiocarbamic acid sodium salt trihydrate into the No. 2 beaker, and continuously stir for 10min to form a mixed uniform solution;

[0053] Step four: use a clean 25ml measuring cylinder to measure 15ml triethylamine, and add it into the No. 2 beaker, and continuously stir for 10min to form a mixed uniform solution;

[0054] Step five: keep the temperature at 20-40℃, the stirring speed of the stirring device in the No. 2 beaker at 600 rpm, quickly pour the solution in the No. 1 beaker into the No. 2 beaker, and stir for 2 h to form the sulfur source modified ZIF-8, which is marked as S-ZIF-8;

[0055] Step six: use a filter funnel with an inner diameter of 8 cm to filter the product in the No. 2 beaker, and use 500 ml of deionized water to wash the product during the filtering process;

[0056] Step seven: move the funnel containing the washed product into the constant temperature drying oven with the hole tin foil, dry at 80℃ for 10 h, cool down, grind the product and put it into a clean ceramic capsule, under argon atmosphere, use a temperature rising rate of 5℃ / min to rise to temperature T and keep it for 4 h, temperature T includes 500℃, 600℃, 700℃ and 800℃, after cooling down, get the catalyst, mark the catalyst as Zn-NSC-T, test the catalyst activity, after testing, save the sample bag for later use.

[0057] T in Zn-NSC-T can be 500, 600, 700 and 800, and the corresponding temperature T is 500℃, 600℃, 700℃ and 800℃, as follows:

[0058] Synthesis of Zn-NSC-500 catalyst: transfer the prepared S-ZIF-8 precursor to a ceramic capsule, heat to 500℃ at a temperature rising rate of 5℃ / min under argon atmosphere, then keep it for 4 h, after cooling down, get the sample and record it as Zn-NSC-500. The obtained material is directly used without further processing;

[0059] Synthesis of Zn-NSC-600 catalyst: transfer the prepared S-ZIF-8 precursor to a ceramic capsule, heat to 600℃ at a temperature rising rate of 5℃ / min under argon atmosphere, then keep it for 4 h, after cooling down, get the sample and record it as Zn-NSC-600. The obtained material is directly used without further processing;

[0060] Synthesis of Zn-NSC-700 catalyst: transfer the prepared S-ZIF-8 precursor to a ceramic capsule, heat to 700℃ at a temperature rising rate of 5℃ / min under argon atmosphere, then keep it for 4 h, after cooling down, get the sample and record it as Zn-NSC-700. The obtained material is directly used without further processing;

[0061] Synthesis of Zn-NSC-800 catalyst: The prepared S-ZIF-8 precursor was transferred to a ceramic capsule, heated to 800°C at a heating rate of 5°C / min under an argon atmosphere, and then held for 4h. After cooling, the sample was obtained and recorded as Zn-NSC-800. The resulting material was used directly without further processing.

[0062] An application of a zinc-based catalyst for gas-solid phase acetylene hydration reaction, including catalyst activity testing, the catalyst activity testing comprising the following steps:

[0063] S1: Purge the catalyst with N2 to remove impurity gases in the reaction device;

[0064] S2: Perform acetylene hydration reaction in a continuous fixed-bed flow microreactor at normal pressure, the continuous fixed-bed flow microreactor at normal pressure has an inner diameter of 10mm, 2ml of catalyst sample is placed in a tubular reactor, and the tubular reactor is placed in the middle of a reactor furnace;

[0065] S3: Perform heating, and set the temperature of a condensation circulating pump to -2°C, when the reaction temperature reaches 260°C, the reaction pressure is normal pressure, and the acetylene space velocity is 90h -1 , when the display temperature of the reaction water reaches 170°C, activate the catalyst in the fixed-bed reactor with water vapor through a peristaltic pump at 0.012g·min -1 , and the activation time is thirty minutes;

[0066] S4: Turn off the N2 switch, and after the nitrogen flow meter shows zero, open C2H2, and according to the reaction conditions of GHSV(C2H2)=90h -1 and n(H2O) / n(C2H2)=4, inject acetylene and water vapor into the reactor;

[0067] S5: Every other hour, detect the content of the product by manual injection of gas chromatography to analyze its composition.

[0068] The products obtained by acetylene hydration reaction are quantitatively analyzed using the calibration area normalization method, the conversion rate (X) of acetylene and the selectivity (S) of acetaldehyde are used as the standard for evaluating the performance of zinc-based catalysts in catalyzing acetylene hydration reaction, the main product of acetylene hydration reaction is acetaldehyde, the by-products are acetone and butenal, and there is also unreacted acetylene, the calculation formula of the conversion rate of acetylene and the selectivity of acetaldehyde is:

[0069] X C2H2 =[(φ A0 -φ A ) / φ A0 ]×100%;

[0070] S CH3CHO =[φAA / (φ A0 -φ A )]x100%;

[0071] wherein, φ A0 represents the volume fraction of C2H2 in raw materials, φ A represents the volume fraction of residual C2H2 in products, φ AA represents the volume fraction of CH3CHO in products after reaction, and the higher X is, the more reactants are contained in products, and the higher the conversion rate of C2H2 is, indicating that the consumption of C2H2 is large. S is used to measure the amount of target product acetaldehyde, and the higher the selectivity of acetaldehyde is, the more acetaldehyde is generated in the reaction.

[0072] The conversion rate of acetylene and the selectivity of acetaldehyde of Zn-NSC-T catalysts prepared at different calcination temperatures are shown in the description Figure 1 The test results of catalytic performance show that the performance of Zn-NSC-T catalyst is best when the calcination temperature is 600 DEG C. The selectivity of acetaldehyde of the optimal Zn-NSC-600 catalyst is still about 74% after 16h of reaction, indicating that the nitrogen and sulfur co-doped carbon zinc-based catalyst prepared at a suitable calcination temperature can better overcome the problem of high initial selectivity of acetaldehyde and rapid decline of Zn-based catalyst.

[0073] The catalyst prepared in the embodiment of the application is subjected to various characterization tests.

[0074] The loss of active components is an important factor for catalyst deactivation. In order to study the anti-loss performance of the catalyst, the ICP-OES test is performed on the catalyst of Zn-NSC-600 after 16h of reaction and the fresh catalyst, and the results are shown in Table 1, and Table 1 is shown as follows. The loss rate of Zn in Zn-NSC-600 catalyst is only 0.5%, and the results show that the Zn-NSC-600 catalyst has good anti-loss performance and exhibits excellent catalytic performance in acetylene hydration.

[0075] Table 1

[0076]

[0077] X-ray diffraction technology is used to analyze the crystal phase structure of the catalyst, and the results are shown in the description Figure 2 The catalyst before reaction does not detect the diffraction peak of Zn-containing substances, indicating that the Zn active component has good dispersity.

[0078] Carbon deposition is an important factor for catalyst deactivation. In order to study the anti-carbon deposition performance of the catalyst, the TG characterization analysis is performed on the catalyst of Zn-NSC-600 after 16h of reaction and the fresh catalyst, and the results are shown in the description Figure 3As shown, the carbon deposition was calculated by estimating the weight difference between the new catalyst and the old catalyst in the same temperature range, and the weight loss difference of the catalyst at 400-900°C can be considered as the carbon deposition. The amount of carbon deposition of Zn-NSC-600 catalyst was only 0.15%, and the results showed that the Zn-NSC-600 catalyst had good thermal stability and anti-carbon deposition performance, and therefore exhibited good catalytic performance in the acetylene hydration reaction.

[0079] The surface electronic structure of the Zn-NSC-600 catalyst was analyzed by X-ray photoelectron spectroscopy (XPS) technology, and the results are shown in the accompanying drawings of the specification. Figure 4 As shown, the XPS full spectrum of the Zn-NSC-600 catalyst confirmed the existence of Zn, N, S and C atoms, and there were two characteristic peaks S2p 3 / 2 (161.56 eV) and S2p 1 / 2 (163.99 eV) in the X-ray photoelectron spectrum of S2p, indicating the existence of C-S-C(N). No Zn-S signal was observed in the S2p spectrum, indicating that there was no direct coordination relationship between the S species and the Zn species. As can be seen from the C1s spectrum of the Zn-NSC catalyst, after S doping, the peak of the C-S bond (285.99 eV) was observed in the C1s spectrum of the Zn-NSC, indicating that the S atoms were doped in the carbon carrier in the form of C-S bonds.

[0080] The catalyst was structurally characterized by X-ray absorption fine structure spectroscopy (XAFS), and the local coordination structure of the Zn-NSC-600 catalyst was analyzed, and the results are shown in the accompanying drawings of the specification. Figure 5 The results of Zn K edge (XANES) spectrum showed that the absorption edge of the Zn-NSC-600 catalyst was between the absorption edges of Zn foil and ZnO, indicating that the valence of Zn species in the Zn-NSC-600 catalyst was between 0 and +2. The results of extended X-ray absorption fine structure (EXAFS) spectrum showed that there was only one main peak at 1.5 µm for the Zn-NSC-600, similar to zinc phthalocyanine, which was attributed to the Zn-N path. No signal of Zn-Zn path (about 2.3 µm) and Zn-S path (about 1.8 µm) was observed, indicating that in the atomic structure of the Zn-NSC-600, Zn was only coordinated with N, but not with sulfur. The Zn-NSC-600, Zn foil and ZnPc were fitted to further understand the structural parameters of the metal atoms in the material, and the EXAFS structural parameters are listed in Table 2, as shown below, and the results showed that the Zn atom was coordinated with three N atoms, and the Zn-N bond length was 2.00 Å.

[0081] Table 2

[0082]

[0083] (a CN : coordination number; b R : distance between absorber and backscatter atoms; c σ 2 : Debye-Waller factor to account for both thermal and structural disorders; d ΔΕ0: inner potential correction; R factor indicates the goodness of the fit. S0 2 was fixed to 0.87. A reasonable range of EXAFS fitting parameters: 0.600 < S0 2 < 1.000; CN > 0; σ 2 > 0 A 2 | ΔE0 | < 15 eV; R factor < 0.02)

[0084] It will be apparent to those skilled in the art that the application is not limited to the details of the foregoing exemplary embodiments and that the present application can be implemented in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalents of the claims are therefore intended to be embraced therein. No feature of the application is considered critical unless otherwise indicated herein.

Claims

1. A zinc-based catalyst for gas-solid phase acetylene hydration reaction, characterized in that: The zinc-based catalyst includes a zinc source, an organic ligand, a deprotonating agent, and a sulfur source dopant; The zinc source is zinc chloride; The organic ligand is 2-methylimidazole; The deprotonating agent is triethylamine; The sulfur source dopant is sodium diethyldithiocarbamate trihydrate; The zinc-based catalyst uses metal organic framework ZIF-8 as a precursor and is calcined to form a carbon material.

2. A method for preparing a zinc-based catalyst for gas-solid phase acetylene hydration reaction, characterized in that: The steps include: Step 1: Prepare two clean 500ml beakers and mark them as No. 1 and No.

2. Add 200ml of deionized water and a magnetic stirrer to each beaker. Turn on the magnetic stirrer and adjust the stirrer temperature to 20-40℃ and the stirring rate to 500rpm. Step 2: Add 1.35 g of zinc chloride to beaker 1 while maintaining the temperature at 20-40°C and stirring at 500 rpm. Continue stirring for 10 minutes to form a uniform solution. Step 3: While maintaining the temperature at 20-40°C and stirring at a rate of 500 rpm, add 6.5 g of 2-methylimidazole to beaker No. 2 and stir for 10 minutes to completely dissolve the 2-methylimidazole. Then, add 1 g of sodium diethyldithiocarbamate trihydrate to beaker No. 2 and continue stirring for 10 minutes to form a mixed solution; Step 4: Use a clean 25ml graduated cylinder to measure 15ml of triethylamine and add it to beaker No.

2. Stir continuously for 10 minutes to form a mixed solution. Step 5: While maintaining the temperature at 20-40°C and the stirring rate of the stirrer in beaker No. 2 at 600 rpm, the solution in beaker No. 1 was quickly poured into beaker No. 2 and stirred for 2 hours to form sulfur-modified ZIF-8, which was labeled as S-ZIF-8; Step 6: Use a suction funnel with an inner diameter of 8 cm to filter the product in beaker No.

2. During the filtration process, use 500 ml of deionized water to wash the product; Step 7: Move the funnel containing the washed product into a constant temperature drying oven with a perforated tin foil and dry it at 80°C for 10 hours. After cooling, grind the product and place it in a clean ceramic ark. Under an argon atmosphere, heat it to temperature T at a rate of 5°C / min and keep it warm for 4 hours. After cooling, obtain the catalyst, which is labeled Zn-NSC-T. Perform a catalytic activity test on the catalyst and store it in a sample bag for later use.

3. The method for preparing a zinc-based catalyst for gas-solid phase acetylene hydration reaction according to claim 2, characterized in that: The temperature T is 500°C, 600°C, 700°C or 800°C.

4. A use of the zinc-based catalyst for gas-solid phase acetylene hydration reaction as claimed in claim 1, comprising a catalyst activity test, characterized in that: The catalyst activity test includes the following steps: S1: Use N2 to purge the catalyst to remove impurity gases in the reaction device; S2: Acetylene hydration reaction was carried out in a continuous fixed-bed flow microreactor at atmospheric pressure. The inner diameter of the continuous fixed-bed flow microreactor at atmospheric pressure was 10 mm. 2 ml of catalyst sample was placed in the tubular reactor, and the tubular reactor was placed in the middle of the reactor furnace. S3: Heating is performed and the condensation circulation pump temperature is set to -2°C. When the reaction temperature reaches temperature S1 and the displayed temperature of the reaction water reaches temperature S2, the catalyst in the fixed bed reactor is activated with water vapor at a rate of 0.012 g min-1 by a peristaltic pump. -1 , activation time is thirty minutes; S4: Turn off the N2 switch, wait until the nitrogen flow meter shows zero, then turn on the C2H2, according to and the reaction conditions of n(H2O) / n(C2H2)=4, acetylene and water vapor were injected into the reactor; S5: The product content was checked every hour by manual injection of gas chromatography.

5. The use of a zinc-based catalyst for gas-solid phase acetylene hydration reaction according to claim 4, characterized in that: The main product of the acetylene hydration reaction is acetaldehyde, and the by-products include acetone and crotonaldehyde, as well as acetylene that has not participated in the reaction.

6. The use of a zinc-based catalyst for gas-solid phase acetylene hydration reaction according to claim 5, characterized in that: The calculation formula for the conversion rate of acetylene and the selectivity of acetaldehyde is: X C2H2 =[(φ A0 -f A ) / φ A0 ]×100%; S CH3CHO =[φ AA / (φ A0 -f A )]×100%; Among them, φ A0 Indicates the volume fraction of C2H2 in the raw material, φ A represents the volume fraction of C2H2 remaining in the product, φ AA Represents the volume fraction of CH3CHO in the reaction product.

7. The use of a zinc-based catalyst for gas-solid phase acetylene hydration reaction according to claim 4, characterized in that: The temperature S1 is 260°C.

8. The use of a zinc-based catalyst for gas-solid phase acetylene hydration reaction according to claim 4, characterized in that: The temperature S2 is 170°C.

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