A preparation method of an anti-pulverization catalyst for synthesizing high-concentration COS

Abstract

The invention discloses a preparation method of an anti-pulverization catalyst for synthesizing high-concentration COS, and the specific steps are as follows: Dissolve ammonium ferric citrate and calcium chloride in deionized water, add ethylene glycol and urea, stir and mix evenly, and let stand for 2 to 24 hours, then pour it into an ultrasonic atomizer for atomization treatment to form an atomized mixed solution; Introduce the atomized mixed solution into a high-temperature tubular furnace by pressurized carbon dioxide gas for heating and decomposition, and collect the sample powder generated by decomposition through electrostatic adsorption; Place the sample powder in a sugar coating machine, spray an atomized liquid containing a granulating agent for granulation to form spherical structures; Roast the spherical structures and then perform sulfidation treatment to obtain the required anti-pulverization catalyst for synthesizing high-concentration COS. The catalyst prepared by the invention has the characteristics of long service life, high mechanical strength, low loss rate, and strong anti-pulverization ability. When used in the dry method for preparing COS, the catalyst has a high conversion rate of CO and good selectivity for the product COS.

Description

Technical Field

[0001] The present invention relates to the technical field of catalyst preparation, and particularly relates to a preparation method of an anti-pulverization type catalyst for synthesizing high-concentration COS. Background Art

[0002] Carbonyl sulfide, with the chemical formula COS and also known as carbon oxysulfide, is often used as a raw material for chemical reaction intermediates and is widely applied in the synthesis of pesticides, pharmaceuticals, and other chemical products; it can also be used as a fumigant for protecting grain storage. In recent years, high-purity COS has been used as a substitute for fluoride gas in the etching of electronic components, and its development trend is quite rapid.

[0003] Currently, there are generally two categories of methods for synthesizing carbonyl sulfide: wet method and dry method. The most commonly used wet method is the reaction of sulfuric acid with ammonium thiocyanate. For example, CN110127702A discloses a method and device for preparing carbonyl sulfide gas, which includes co-currently dropping ammonium thiocyanate solution and concentrated sulfuric acid into a sulfuric acid solution with a certain concentration for reaction, and the generated carbon oxysulfide gas is filled after condensation, drying, and compression. The dry synthesis method, as disclosed in patents such as CN205653172U, CN205683986U, and CN114669298A, mainly involves reacting CO and sulfur vapor under the condition of a catalyst (such as calcium chloride, iron sulfide, etc.) to generate carbonyl sulfide. This method has the characteristics of simple process, high yield, and environmental friendliness, and is the preferred method for industrial large-scale production of carbonyl sulfide gas.

[0004] The catalysts used in the dry production of carbonyl sulfide are generally molecular sieves and metal sulfide materials. Among them, the molecular sieve has poor selectivity for COS, generally only about 65%. For metal sulfides, such as catalysts like NiS, CrS, CoS, WS, SnS, and FeS, their activity and selectivity can reach more than 90%. However, the state of these metal sulfide catalysts before use is generally their corresponding oxides, and they need to be sulfided into the corresponding sulfides during the reaction to have catalytic activity. However, precisely this sulfidation treatment causes the original oxygen element with a smaller ionic radius to be replaced by a sulfur element with a larger ionic radius, resulting in the catalyst being prone to pulverization. The pulverization of the catalyst not only increases the resistance of the reaction bed layer, but also significantly generates by-products carbon dioxide and carbon disulfide, reducing the yield of COS and increasing the purification cost of COS. Therefore, such catalysts generally need to be replaced after one month of use, and their service life is short. Summary of the Invention

[0005] In view of the technical deficiencies of the above-mentioned existing catalysts, such as easy pulverization, short service life, and poor product selectivity, the present invention provides a preparation method of an anti-pulverization catalyst, and prepares a catalyst with strong anti-pulverization performance for synthesizing high-concentration COS. Compared with the existing commercial catalysts, it has the characteristics of high mechanical strength, strong anti-pulverization performance, low loss rate, and long service life. When used in the dry method for preparing COS, it has a high CO conversion rate and good selectivity for the product COS.

[0006] The present invention adopts the following technical solutions:

[0007] A preparation method of an anti-pulverization catalyst for synthesizing high-concentration COS, comprising the following steps:

[0008] S1. Dissolve ammonium ferric citrate and calcium chloride in deionized water, add ethylene glycol and urea, and let the mixed solution obtained after stirring and mixing evenly stand at a certain temperature for 2 to 24 hours, and then pour the mixed solution into an ultrasonic atomizer for atomization treatment to form an atomized mixed solution;

[0009] S2. Introduce the atomized mixed solution obtained in step S1 into a high-temperature tubular furnace with pressurized carbon dioxide gas for heating and decomposition, and collect the sample powder generated by decomposition through electrostatic adsorption;

[0010] S3. Place the sample powder in a sugar coating machine, spray an atomized liquid containing a granulating agent for granulation into balls to obtain a spherical structure;

[0011] S4. Roast the spherical structure at 900 to 1100 °C for 4 to 12 hours, and then perform a sulfidation treatment to obtain the required anti-pulverization catalyst for synthesizing high-concentration COS.

[0012] The mass ratio of ammonium ferric citrate, calcium chloride, deionized water, ethylene glycol, and urea added in step S1 is (1-5):(1-4):(50-100):(1-2):(1-5).

[0013] The standing temperature of the mixed solution in step S1 is 70 to 90 °C.

[0014] The atomization rate of the atomization treatment in step S1 is 10 to 200 mL / h; the size of the ultrasonic atomized droplets is 1 to 10 microns.

[0015] The inlet pressure of the pressurized carbon dioxide gas in step S2 is 0.05 to 0.8 MPa, and the inlet gas volume is 1000 to 5000 times the volume of the atomized mixed solution.

[0016] The atomized liquid sprayed in step S3 is an aqueous solution containing a granulating agent. The ratio of the added powder to the granulating agent is not limited, mainly for formability. Generally, 0.1 mol / L of atomized liquid is sprayed until forming. The ratio of the liquid mass to the powder is generally 1:5.

[0017] The granulating agent added in step S3 is one or more of silica gel solution, aluminum hydroxide sol solution, and sodium carboxymethyl cellulose solution.

[0018] The technical solution of the present invention has the following advantages:

[0019] In the present invention, an organic iron source and an inorganic calcium source are effectively mixed under the action of a solvent, and quickly combined into a uniform composite system after atomized high-temperature treatment. Finally, after high-temperature treatment, a catalyst for synthesizing COS with strong anti-pulverization performance is formed. Compared with the existing commercial catalysts, it has the characteristics of high mechanical strength, strong anti-pulverization performance, low loss rate, and long service life. When used in the dry method for preparing COS reaction, it has a high CO conversion rate and good selectivity for the product COS. Specific Embodiments

[0020] The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. Example 1

[0021] This example provides a preparation method for a sulfided hydrodeoxygenation and isomerization catalyst, including the following steps:

[0022] S1. Dissolve 5.6 grams of ammonium ferric citrate and 4.2 grams of calcium chloride in 100 ml of deionized water, add 6 grams of ethylene glycol and 3.5 grams of urea, and let the stirred and mixed solution stand at 80 °C for 4 hours. Then pour the mixed solution into an ultrasonic atomizer for atomization treatment with an atomization rate of 15 mL / h to form an atomized mixed solution;

[0023] S2. Introduce carbon dioxide gas at 0.1 MPa into the atomizer with a flow rate of 0.4 m 3 / h. The atomized vapor carried out directly enters a quartz glass tube with an inner diameter of 100 mm for thermal decomposition. The quartz glass tube is placed in a high-temperature tubular furnace at 950 °C. The isothermal zone of the high-temperature tubular furnace is greater than 10 cm, and the pyrolyzed sample powder is collected by electrostatic adsorption;

[0024] S3. Place the sample powder in a sugar coating machine, spray an atomized liquid containing 0.1 mol / L of sodium carboxymethyl cellulose solution for granulation into spheres to obtain spherical structures;

[0025] S4. Roast the spherical structure at 1000 °C for 4 hours. After sulfiding the obtained spherical sample with hydrogen sulfide gas, it is used in the reaction for synthesizing high-concentration COS. The concentration of the generated product COS reaches 93.5%, and the loss rate after the catalyst is continuously used for 10 days is lower than 2.1%. Example 2

[0026] This example provides a preparation method of a sulfided hydrodeoxygenation and isomerization catalyst, including the following steps:

[0027] S1. Dissolve 43.3 g of ammonium ferric citrate and 38.1 g of calcium chloride in 1000 ml of deionized water, add 52 g of ethylene glycol and 22 g of urea. The solution after stirring and mixing evenly is left standing at 90 °C for 2 hours, and then the mixed solution is poured into an ultrasonic atomizer for atomization treatment. The atomization rate is 10 mL / h to form an atomized mixed solution;

[0028] S2. Pass carbon dioxide gas with a pressure of 0.8 MPa into the atomizer, with a flow rate of 0.4 m 3 / h. The entrained atomized vapor directly enters a quartz glass tube with an inner diameter of 100 mm for thermal decomposition. The quartz glass tube is placed in a high-temperature tube furnace at 930 °C. The isothermal zone of the high-temperature tube furnace is greater than 10 cm. The pyrolyzed sample powder is collected by electrostatic adsorption;

[0029] S3. Place the sample powder in a sugar coating machine, and spray an atomized liquid containing 0.1 mol / L of aluminum hydroxide solution to granulate into spheres to obtain a spherical structure;

[0030] S4. Roast the spherical structure at 1100 °C for 12 hours. After sulfiding the obtained spherical sample with hydrogen sulfide gas, it is used in the reaction for synthesizing high-concentration COS. The concentration of the generated product COS reaches 92.8%, and the loss rate after the catalyst is continuously used for 10 days is lower than 3.2%. Example 3

[0031] This example provides a preparation method of a sulfided hydrodeoxygenation and isomerization catalyst, including the following steps:

[0032] S1. Dissolve 5.6 g of ammonium ferric citrate and 4.2 g of calcium chloride in 100 ml of deionized water, add 6 g of ethylene glycol and 3.5 g of urea. The solution after stirring and mixing evenly is left standing at 70 °C for 24 hours, and then the mixed solution is poured into an ultrasonic atomizer for atomization treatment. The atomization rate is 200 mL / h to form an atomized mixed solution;

[0033] S2. Pass carbon dioxide gas with a pressure of 0.05 MPa into the atomizer, with a flow rate of 0.4 m 3 / h, the atomized vapor carried out directly enters a quartz glass tube with an inner diameter of 100 mm for thermal decomposition. The quartz glass tube is placed in a high-temperature tube furnace at 950 °C. The isothermal zone of the high-temperature tube furnace is greater than 10 cm. The pyrolyzed sample powder is collected by electrostatic adsorption;

[0034] S3. Place the sample powder in a sugar coating machine, spray an atomized liquid containing a 0.1 mol / L sodium carboxymethyl cellulose solution for granulation into spheres to obtain spherical structures;

[0035] S4. Calcinate the spherical structures at 900 °C for 4 hours. After sulfiding the obtained spherical samples with hydrogen sulfide gas, use them in the reaction for synthesizing high-concentration COS. The concentration of the generated product COS reaches 93.1%, and the loss rate of the catalyst after continuous use for 10 days is lower than 2.4%. Example 4

[0036] This example provides a preparation method of a sulfided hydrodeoxygenation and isomerization catalyst, including the following steps:

[0037] S1. Dissolve 10 grams of ammonium ferric citrate and 10 grams of calcium chloride in 1000 ml of deionized water, add 20 grams of ethylene glycol and 50 grams of urea. The solution after stirring and mixing evenly is left standing at 90 °C for 2 hours, and then the mixture is poured into an ultrasonic atomizer for atomization treatment. The atomization rate is 10 mL / h to form an atomized mixture;

[0038] S2. Pass carbon dioxide gas at 0.8 MPa into the atomizer, with a flow rate of 0.4 m 3 / h, the atomized vapor carried out directly enters a quartz glass tube with an inner diameter of 100 mm for thermal decomposition. The quartz glass tube is placed in a high-temperature tube furnace at 930 °C. The isothermal zone of the high-temperature tube furnace is greater than 10 cm. The pyrolyzed sample powder is collected by electrostatic adsorption;

[0039] S3. Place the sample powder in a sugar coating machine, spray an atomized liquid containing a 0.1 mol / L aluminum hydroxide solution for granulation into spheres to obtain spherical structures;

[0040] S4. Calcinate the spherical structures at 1100 °C for 12 hours. After sulfiding the obtained spherical samples with hydrogen sulfide gas, use them in the reaction for synthesizing high-concentration COS. The concentration of the generated product COS reaches 91.9%, and the loss rate of the catalyst after continuous use for 10 days is lower than 2.6%. Example 5

[0041] This example provides a preparation method of a sulfided hydrodeoxygenation and isomerization catalyst, including the following steps:

[0042] S1. Dissolve 50 g of ammonium ferric citrate and 40 g of calcium chloride in 500 ml of deionized water, add 10 g of ethylene glycol and 10 g of urea, and let the stirred and mixed solution stand at 70 °C for 24 hours. Then pour the mixed solution into an ultrasonic nebulizer for atomization treatment at an atomization rate of 200 mL / h to form an atomized mixed solution.

[0043] S2. Pass carbon dioxide gas at 0.05 MPa into the nebulizer at a flow rate of 0.4 m 3 / h. The atomized vapor carried out directly enters a quartz glass tube with an inner diameter of 100 mm for thermal decomposition. The quartz glass tube is placed in a high-temperature tubular furnace at 950 °C. The isothermal zone of the high-temperature tubular furnace is greater than 10 cm. Electrostatic adsorption is used to collect the pyrolyzed sample powder.

[0044] S3. Place the sample powder in a sugar coating machine, and spray an atomized liquid containing a 0.1 mol / L sodium carboxymethyl cellulose solution for granulation into spheres to obtain spherical structures.

[0045] S4. Calcinate the spherical structures at 900 °C for 4 hours. After sulfiding the obtained spherical samples with hydrogen sulfide gas, use them in the reaction for synthesizing high-concentration COS. The concentration of the generated product COS reaches 91.9%, and the loss rate of the catalyst after continuous use for 10 days is lower than 2.2%.

[0046] The following table is a comparison table of the use effects of commercially available catalysts and Examples 1-3 of this application.

[0047] Comparison Table of Catalyst Use Effects

[0048]

[0049] In summary, in the present invention, the organic iron source and the inorganic calcium source are effectively mixed under the action of a solvent, and are quickly combined into a uniform composite system after atomization and high-temperature treatment. Finally, after high-temperature treatment, a catalyst for synthesizing COS with strong anti-pulverization performance is formed. Compared with the existing commercially available catalysts, it has the characteristics of high mechanical strength, strong anti-pulverization performance, low loss rate, and long service life. When used in the dry method for preparing COS reaction, it has a high CO conversion rate and good selectivity for the product COS.

[0050] What is not described in the present invention is applicable to the prior art.

[0051] Obviously, the above embodiments are only examples clearly described and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.

Claims

1. A preparation method of an anti-pulverization catalyst for synthesizing high-concentration COS, characterized in that, It includes the following steps: S1. Dissolve ammonium ferric citrate and calcium chloride in deionized water, add ethylene glycol and urea, stir and mix evenly, let the mixed solution stand at a certain temperature for 2 to 24 hours, and then pour the mixed solution into an ultrasonic atomizer for atomization treatment to form an atomized mixed solution; S2. Introduce the atomized mixed solution obtained in step S1 into a high-temperature tubular furnace for heating decomposition with pressurized carbon dioxide gas, and collect the sample powder produced by electrostatic adsorption; S3. Place the sample powder in a sugar coating machine, spray an atomized liquid containing a granulating agent for granulation into balls to obtain a spherical structure; S4. Calcine the spherical structure at 900 - 1100 °C for 4 to 12 hours, and then perform a sulfidation treatment to obtain the required anti-pulverization catalyst for synthesizing high-concentration COS; Among them, the mass ratio of ammonium ferric citrate, calcium chloride, deionized water, ethylene glycol, and urea added in step S1 is (1 - 5):(1 - 4):(50 - 100):(1 - 2):(1 - 5).

2. The preparation method according to claim 1, characterized in that, The standing temperature of the mixed solution in step S1 is 70 - 90 °C.

3. The preparation method according to claim 1, characterized in that, The atomization rate of the atomization treatment in step S1 is 10 - 200 mL / h; the size of the ultrasonic atomized droplets is 1 - 10 microns.

4. The preparation method according to claim 1, wherein The inlet pressure of the pressurized carbon dioxide gas in step S2 is 0.05 - 0.8 MPa, and the inlet gas volume is 1000 - 5000 times the volume of the atomized mixed solution.

5. The preparation method according to claim 1, wherein The granulating agent added in step S3 is one or more of silica gel solution, aluminum hydroxide sol solution, and sodium carboxymethyl cellulose solution.

6. An anti-pulverization catalyst prepared by the preparation method according to any one of claims 1 - 5.

Images