Composite purifying agent as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of deoxidizing agents, and relates to a compound purifying agent as well as a preparation method and application thereof. The preparation method of the composite purifying agent comprises the following steps: (1) preparing a zinc-containing alumina gel solution in proportion, mixing the zinc-containing alumina gel solution with manganese carbonate, and grinding to obtain a reaction solution; and (2) carrying out spray dispersion on the reaction solution, dropwise adding the reaction solution into an alcohol receiving solution of organic amine in a liquid drop form, collecting the receiving solution and reactants, and carrying out hydrothermal aging to promote the reaction. After aging, washing and drying to obtain reactant particles; and (3) adding a binder into the reactant particles, carrying out extrusion molding or granulation, and carrying out drying and low-temperature roasting to obtain the composite purifying agent. Compared with the prior art, the obtained composite purifying agent can tolerate sulfur-containing conditions, is rich in pore structure, high in wear resistance and high in deoxidation efficiency, and can be applied to low-temperature deoxidation.

Description

Technical Field

[0001] This invention belongs to the field of deoxidizer technology, and relates to a composite purifying agent, its preparation method and application. Background Technology

[0002] Olefins, as the core raw material of the polymerization industry, are widely used in the production of polymer materials such as polypropylene and polyethylene. With the commercial application of new polymerization catalysts such as metallocene (e.g., zirconium diacene complex catalysts), their single active center and high polymerization selectivity have significantly improved product performance, but have also imposed strict requirements on the purity of the raw material gas. The oxygen impurity content in polymerization-grade olefins must be controlled below 0.1 ppm, and some high-end processes even require ≤0.01 ppm. This is because oxygen impurities have the following hazards: (1) Oxygen will react with olefins to generate peroxides, which will cause problems such as yellowing and abnormal cross-linking of the polymerization products, reducing the mechanical properties and processing stability of the products; (2) Trace amounts of oxygen can form irreversible coordination bonds with the active center of the catalyst, causing permanent poisoning and deactivation of the catalyst. At the same time, the exothermic oxidation reaction may cause the temperature of the reaction system to rise sharply, threatening the safe operation of the equipment.

[0003] Manganese-based deoxidizers, with metallic manganese (Mn), ferromanganese alloy (Fe-Mn), or manganese-based composite oxides as core components, have advantages such as strong deoxidation ability, low cost, and environmental friendliness, and are one of the mainstream deoxidizers currently available. Traditional deoxidizers face two major challenges: (1) Industrial raw gas often contains sulfides such as H2S and COS, which can accelerate the deactivation of deoxidizers and amplify the harm of impurities. (2) Insufficient wear resistance design, poor bonding between the manganese matrix and additives (such as binders and pore-forming agents), easy interface peeling under friction or fluid shear, resulting in pulverization, and pulverization can easily cause local exothermic runaway, posing a safety hazard. Although ordinary manganese-based deoxidizers are low in cost and have good deoxidation performance, they have problems such as high wear powdering and easy generation of manganese sulfide in sulfur-containing atmospheres, which lead to pore blockage, decreased activity, and significantly reduced performance. As sulfur-containing impurities in industrial raw gas are difficult to avoid, the development of new deoxidizers with both high deoxidation efficiency, sulfur resistance, and wear resistance has become an urgent need in the industry.

[0004] Chinese patent CN100513367C discloses the preparation of a manganese-based deoxidizer, which is an olefin deoxidizer using alkaline earth metal oxides and alumina as active promoters to improve the deoxidation capacity of the deoxidizer. However, this patented product uses manganese oxides (MnO / Mn3O4) as the main active component, has no sulfur resistance, and is easily deactivated in a sulfur-containing atmosphere.

[0005] Chinese patent CN102850159B discloses a deoxidizer with manganese oxide, titanium oxide, and silver as active components. This deoxidizer can be used to remove oxygen from olefins, with a deoxidation depth of less than 0.01 ppm. However, this patent uses precious metals as the main active components, which are easily deactivated in a sulfur-containing atmosphere.

[0006] Chinese patent CN108014629A discloses a deoxidizer with sulfur resistance and its preparation method. It uses iron and manganese oxides and modified molecular sieves as the main active components to improve its sulfur resistance. However, it uses iron compounds, such as iron oxide red and iron hydroxide, for desulfurization, resulting in poor sulfur resistance precision.

[0007] Existing technologies have not effectively solved the problem of poisoning and deactivation of manganese-based deoxidizers in sulfurized environments. Currently, the industry urgently needs a manganese-based deoxidizer that can operate stably under sulfur-containing conditions and has high wear resistance. Summary of the Invention

[0008] The purpose of this invention is to overcome the defects of the prior art by providing a composite purifying agent, its preparation method, and its application.

[0009] The objective of this invention can be achieved through the following technical solutions: A method for preparing a composite purifying agent includes the following steps: (1) Mix and grind the zinc-aluminum glue solution with manganese carbonate to obtain a reaction solution; (2) Spray the reaction solution obtained in step (1) into the receiving liquid in the form of droplets, and then perform aging, filtration, washing and drying in sequence to obtain the reaction product; (3) The reaction product obtained in step (2) is mixed with the binder and then extruded or granulated. After drying and low-temperature calcination, a composite purifying agent is obtained.

[0010] Further, in step (1), the zinc-aluminum adhesive solution is prepared by mixing basic zinc carbonate and boehmite, and then dissolving them in nitric acid.

[0011] Furthermore, in the zinc-aluminum adhesive solution, the content of aluminum source (calculated as alumina) is 10-20 wt%, and the content of zinc source (calculated as zinc oxide) is 5-10 wt%.

[0012] Further, in step (1), the mass ratio of the zinc-aluminum adhesive solution to manganese carbonate is 100:(20~40); the grinding is carried out by ball milling, and the grinding time is not less than 15 minutes.

[0013] Further, in step (2), the receiving liquid is an alcoholic solution of organic amine with a mass concentration of 5-10%.

[0014] Furthermore, the organic amine is selected from one or more of diethylamine, triethylamine, ethanolamine, or diethanolamine; the alcohol is selected from one or two of ethanol or isopropanol.

[0015] Further, in step (2), the spray is a pressure spray with a spray pressure of 0.2~0.5 MPa; the aging conditions are: temperature 30~60 ℃, aging time 4~12 h; and the drying temperature is 80~150 ℃.

[0016] Further, in step (3), the mass ratio of the reaction product to the binder is (80~90):(10~20); The adhesive is selected from one or more of high-alumina cement, attapulgite, alumina glue, or clay. The granulation process is performed by roller granulation, sugar coating machine granulation, disc granulation, or extrusion granulation, and the particle size of the granulated particles ranges from 1.6 to 3.0 mm. The drying temperature is 80~150℃; The roasting temperature is 250~500 ℃, and the roasting time is 2~5 h.

[0017] The present invention also provides a composite purifying agent, which is prepared by the method described in any of the preceding claims.

[0018] The present invention also provides an application of the composite purifier as described above, wherein the composite purifier is applied to deoxygenation treatment under sulfur-containing conditions.

[0019] Compared with the prior art, the present invention has the following beneficial effects: (1) The purifier prepared by the present invention has high activity. By mixing and grinding manganese carbonate with zinc-aluminum glue, the active components manganese and zinc are highly dispersed on the surface of alumina sol. Then, the dispersion system is sprayed into an alcohol solution of organic amine. Under the action of the alcohol solution of organic amine, the dispersed active components slowly aggregate to form a three-dimensional interconnected porous network structure, while avoiding the agglomeration of active particles before high-temperature calcination. Finally, a purifier sample with high specific surface area is obtained by mild drying and calcination process.

[0020] The high specific surface area gives the manganese oxide obtained by roasting and decomposition more active centers, and the excellent pore size distribution characteristics of the purifier can promote the rapid entry of reactants into the pores and full contact with the active centers, thereby significantly improving the reaction efficiency of the purifier.

[0021] (2) The purifying agent prepared by this invention has good strength and wear resistance. The reaction solution is introduced into the alcohol solution of organic amine by spraying. The active components in the reaction system undergo cross-linking and curing reaction with the organic amine. After molding, drying and calcination, a dense and firmly bonded three-dimensional network skeleton is formed, thereby giving the purifying agent excellent mechanical strength and wear resistance.

[0022] (3) The purifying agent prepared by the present invention is prepared by manganese carbonate and zinc-aluminum colloid. After calcination, it is converted into metal oxides. The product has manganese oxide, zinc oxide, aluminum oxide and other main active components. Zinc is highly dispersed on the surface of aluminum oxide sol. After subsequent curing and calcination, it is dispersed in the pore structure of the cured aluminum oxide in the form of zinc oxide. Zinc oxide preferentially reacts with hydrogen sulfide, which can effectively desulfurize and make the deoxidizer resistant to the application under sulfur-containing conditions.

[0023] (4) The composite purifier of the present invention is a composite metal oxide system, which has a high specific surface area, rich material pore structure, high strength and low wear. It not only has high reactivity, but also excellent sulfur resistance. It can play a stable role in the deoxygenation scenario of low oxygen concentration raw gas and is suitable for complex industrial operating conditions. Detailed Implementation

[0024] The present invention will now be described in detail with reference to specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0025] Unless otherwise specified, all raw materials used in this invention are commercially available products.

[0026] Example 1 A composite purifying agent is prepared according to the following steps: (1) Basic zinc carbonate and boehmite were mixed and dissolved in nitric acid to prepare a zinc-aluminum colloid solution. The aluminum source (calculated as alumina) in the solution had a mass concentration of 15% and the zinc source (calculated as zinc oxide) had a mass concentration of 10%. Subsequently, the zinc-aluminum colloid solution was mixed with manganese carbonate at a mass ratio of 100:30 and ball-milled for 20 min to obtain a reaction solution.

[0027] (2) Using a 5 wt% diethylamine ethanol solution as the receiving liquid, the reaction solution obtained in step (1) was sprayed into the receiving liquid at a pressure of 0.3 MPa. After aging at 40 °C for 8 h, the product was obtained by filtration, washing and drying at 90 °C.

[0028] (3) The reaction product obtained in step (2) is mixed with high alumina cement at a mass ratio of 80:20 and granulated by a sugar coating machine to obtain particles with a particle size of 2~3 mm; the particles are dried at 80 ℃ and then calcined at 350 ℃ for 4 h to obtain the composite purifying agent.

[0029] Comparative Example 1 A purification agent is prepared using the same types of raw materials as in Example 1, and the mass ratio of each raw material is the same as the actual input mass ratio of the corresponding raw materials in Example 1. The only difference is that steps (1) and (2) of Example 1 are omitted. The basic zinc carbonate, boehmite, manganese carbonate and high-alumina cement are mixed evenly and then the same granulation, drying and calcination process as step (3) of Example 1 is used to prepare the purification agent.

[0030] Comparative Example 2 A purification agent is prepared in a manner that is basically the same as that in Example 1, except that: in step (1), basic zinc carbonate is not added, but boehmite is mixed and dissolved with nitric acid to prepare an aluminum sol solution (the aluminum source is calculated as alumina, and the mass concentration is the same as that in Example 1, which is 15%); subsequently, the aluminum sol solution is mixed with manganese carbonate at a mass ratio of 100:30, and the process parameters of the remaining steps are exactly the same as those in Example 1.

[0031] Comparative Example 3 A purification agent, whose preparation method is basically the same as that in Example 1, except that: in step (2), a 5% diethylamine ethanol solution is not used as the receiving liquid, but a 5% ammonia solution is used instead.

[0032] Comparative Example 4 Conventional manganese-based deoxidizers are spherical particles with a particle size of 2-3 mm. The preparation process is as follows: manganese carbonate is mixed with high-alumina cement, granulated, and then calcined at 350 °C. The manganese oxide content in this commercial deoxidizer is about 47%.

[0033] Example 2 A composite purifying agent is prepared according to the following steps: (1) Basic zinc carbonate and boehmite were mixed and dissolved in nitric acid to prepare a zinc-aluminum colloid solution. The aluminum source (calculated as alumina) in the solution had a mass concentration of 10% and the zinc source (calculated as zinc oxide) had a mass concentration of 5%. Subsequently, the zinc-aluminum colloid solution was mixed with manganese carbonate at a mass ratio of 100:40 and ball-milled for 30 min to obtain a reaction solution.

[0034] (2) Using a 5% diethylamine isopropanol solution as the receiving liquid, the reaction solution obtained in step (1) was sprayed into the receiving liquid at a pressure of 0.5 MPa. After aging at 50 °C for 12 h, the product was obtained by filtration, washing and drying at 150 °C.

[0035] (3) The reaction product obtained in step (2) is mixed with attapulgite at a mass ratio of 80:20 and granulated by a sugar coating machine to obtain particles with a particle size of 2~3 mm; the particles are dried at 150 ℃ and then calcined at 400 ℃ for 3 h to obtain the composite purifying agent.

[0036] Example 3 A composite purifying agent is prepared according to the following steps: (1) Basic zinc carbonate and boehmite were mixed and dissolved in nitric acid to prepare a zinc-aluminum colloid solution. The aluminum source (calculated as alumina) in the solution had a mass concentration of 20% and the zinc source (calculated as zinc oxide) had a mass concentration of 10%. Subsequently, the zinc-aluminum colloid solution was mixed with manganese carbonate at a mass ratio of 100:30 and ball-milled for 40 min to obtain a reaction solution.

[0037] (2) Using a 10% diethanolamine ethanol solution as the receiving liquid, the reaction solution obtained in step (1) was sprayed into the receiving liquid at a pressure of 0.2 MPa. After aging at 60 °C for 4 h, the product was obtained by filtration, washing and drying at 100 °C.

[0038] (3) The reaction product obtained in step (2) is mixed with aluminum glue at a mass ratio of 80:20, and granulated by extrusion machine to obtain strip-shaped particles with a diameter of 2.5 mm; the particles are dried at 90 ℃ and then calcined at 300 ℃ for 4 h to obtain the composite purifying agent.

[0039] Example 4 A composite purifying agent is prepared according to the following steps: (1) Basic zinc carbonate and boehmite were mixed and dissolved in nitric acid to prepare a zinc-aluminum colloid solution. The aluminum source (calculated as alumina) in the solution had a mass concentration of 15% and the zinc source (calculated as zinc oxide) had a mass concentration of 5%. Subsequently, the zinc-aluminum colloid solution was mixed with manganese carbonate at a mass ratio of 100:20 and ball-milled for 50 min to obtain a reaction solution.

[0040] (2) Using an ethanol solution of diethylamine and ethanolamine with a mass concentration of 5% as the receiving liquid, the reaction solution obtained in step (1) was sprayed into the receiving liquid at a pressure of 0.4 MPa, aged at 30 °C for 12 h, and then filtered, washed and dried at 130 °C to obtain the reaction product.

[0041] (3) The reaction product obtained in step (2) is mixed with attapulgite at a mass ratio of 90:10 and granulated by a sugar coating machine to obtain spherical particles with a particle size of 1.6~3 mm; the particles are dried at 100 ℃ and then calcined at 500 ℃ for 2 h to obtain the composite purifying agent.

[0042] The purifying agents of Examples 1-4 and Comparative Examples 1-4 were subjected to the following performance tests: Deoxidation capacity: Tested in accordance with the national standard GB / T 31191-2014 "Test method for deoxidation performance of manganese-based deoxidizers at room temperature".

[0043] Deoxidation capacity under sulfur atmosphere (sulfur resistance): Refer to the test apparatus of GB / T 31191-2014, introduce 100 ppm hydrogen sulfide into the test gas, and evaluate its deoxidation capacity under sulfur resistance conditions.

[0044] Crushing resistance: Tested in accordance with the chemical industry standard HG / T 2782-2024 "Determination of crushing resistance of chemical catalyst particles".

[0045] Wear rate: The test was conducted in accordance with the chemical industry standard HG / T 2976-2011 "Determination of Wear Rate of Fertilizer Catalyst".

[0046] Specific surface area: The test was conducted in accordance with the national standard GB / T 19587-2017 "Determination of specific surface area of ​​solid substances by gas adsorption BET method".

[0047] Table 1 Performance test results of the purifying agents prepared in Examples 1-4 and Comparative Examples 1-4 The test results are shown in Table 1. The composite purifier prepared in Example 1 of this invention has a deoxidation capacity of 21.5 mL / g, a deoxidation capacity in a sulfur-containing atmosphere of 19.2 mL / g, a crushing resistance of 94 N / particle, an abrasion rate of 0.15%, and a specific surface area of ​​146 μm. 2 / g.

[0048] The sample prepared in Comparative Example 1 had a deoxidation capacity of 11.6 mL / g, a deoxidation capacity of 8.2 mL / g in a sulfur-containing atmosphere, a crushing resistance of 66 N / particle, an abrasion rate of 1.4%, and a specific surface area of ​​84 μm. 2 / g. Comparative Example 1 directly uses manganese carbonate, basic zinc carbonate, boehmite and binder for molding, the active components cannot be efficiently dispersed, the specific surface area and deoxidation capacity are low, and the wear rate is high.

[0049] The sample prepared in Comparative Example 2 had a deoxidation capacity of 21.8 mL / g, a deoxidation capacity of 12.5 mL / g in a sulfur-containing atmosphere, a crushing resistance of 95 N / particle, an abrasion rate of 0.12%, and a specific surface area of ​​156 μm. 2 / g. Comparative Example 2 used an organic amine system for curing, resulting in a sample with a high specific surface area, high deoxidation capacity, and low abrasion. However, since no zinc active component was introduced, it lacked sulfur resistance, thus its deoxidation performance was significantly reduced in a sulfur-containing atmosphere.

[0050] The sample prepared in Comparative Example 3 had a deoxidation capacity of 17.8 mL / g, a deoxidation capacity of 15.7 mL / g in a sulfur-containing atmosphere, a crushing resistance of 88 N / particle, an abrasion rate of 0.14%, and a specific surface area of ​​109 μm. 2 / g. In Comparative Example 3, the receiving liquid was replaced with ammonia. The aluminum glue in the ammonia quickly agglomerated and solidified, resulting in a significant decrease in the specific surface area of ​​the material and further reducing its deoxidation performance.

[0051] Comparative Example 4 showed a commercially available deoxidation capacity of 21 mL / g, a deoxidation capacity of 11.5 mL / g in a sulfur-containing atmosphere, a crushing resistance of 74 N / particle, an abrasion rate of 0.53%, and a specific surface area of ​​92 μm. 2 / g. It is directly granulated by mixing manganese carbonate and high-alumina cement, and calcined at 350 ℃. The manganese oxide content is 45%. The manganese content of the sample is higher than that of Example 1, but it has a lower specific surface area of ​​only 92 m. 2 / g, and without sulfur-resistant components, therefore under normal testing conditions, the deoxidation capacity is slightly lower than that of Example 1, but the deoxidation capacity is significantly reduced under sulfur-containing atmosphere.

[0052] The composite purifying agents prepared in Examples 2-4 have a deoxidation capacity of 19-22.4 mL / g, a deoxidation capacity in sulfur-containing atmospheres of 17.3-20.4 mL / g, a crushing resistance of 84-112 N / particle, an abrasion rate of 0.17%-0.26%, and a specific surface area of ​​150-194 m². 2 / g. After introducing the zinc active component, the deoxidation capacity of the sample in a sulfur-containing atmosphere was significantly improved, the wear rate was lower than that of commercially available conventional products, and the specific surface area of ​​the sample was effectively increased, which promoted the improvement of deoxidation efficiency.

[0053] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a composite purifying agent, characterized in that, Includes the following steps: (1) Mix and grind the zinc-aluminum glue solution with manganese carbonate to obtain a reaction solution; (2) Spray the reaction solution obtained in step (1) into the receiving liquid in the form of droplets, and then perform aging, filtration, washing and drying in sequence to obtain the reaction product; (3) The reaction product obtained in step (2) is mixed with the binder and then extruded or granulated. After drying and low-temperature calcination, a composite purifying agent is obtained.

2. The method for preparing the composite purifying agent according to claim 1, characterized in that, In step (1), the zinc-aluminum adhesive solution is prepared by mixing basic zinc carbonate and boehmite, and then dissolving them in nitric acid.

3. The method for preparing the composite purifying agent according to claim 2, characterized in that, The zinc-aluminum adhesive solution contains 10-20 wt% aluminum source (calculated as alumina) and 5-10 wt% zinc source (calculated as zinc oxide).

4. The method for preparing the composite purifying agent according to claim 1, characterized in that, In step (1), the mass ratio of the zinc-aluminum adhesive solution to manganese carbonate is 100:(20~40); the grinding is done by ball milling, and the grinding time is not less than 15 minutes.

5. The method for preparing the composite purifying agent according to claim 1, characterized in that, In step (2), the receiving liquid is an alcoholic solution of organic amine with a mass concentration of 5-10%.

6. The method for preparing the composite purifying agent according to claim 5, characterized in that, The organic amine is selected from one or more of diethylamine, triethylamine, ethanolamine, or diethanolamine; the alcohol is selected from one or two of ethanol or isopropanol.

7. The method for preparing the composite purifying agent according to claim 1, characterized in that, In step (2), the spray is a pressure spray with a spray pressure of 0.2~0.5 MPa; the aging conditions are: temperature 30~60 ℃, aging time 4~12 h; and the drying temperature is 80~150 ℃.

8. The method for preparing the composite purifying agent according to claim 1, characterized in that, In step (3), the mass ratio of the reaction product to the binder is (80~90):(10~20). The adhesive is selected from one or more of high-alumina cement, attapulgite, alumina glue, or clay. The granulation process is performed by roller granulation, sugar coating machine granulation, disc granulation, or extrusion granulation, and the particle size of the granulated particles ranges from 1.6 to 3.0 mm. The drying temperature is 80~150℃; The roasting temperature is 250~500 ℃, and the roasting time is 2~5 h.

9. A composite purifying agent, characterized in that, The composite purifying agent is prepared by the method described in any one of claims 1 to 8.

10. An application of the composite purifying agent as described in claim 9, characterized in that, The composite purifying agent is used for deoxygenation treatment under sulfur-containing conditions.

Images