Catalyst for simultaneously removing acetylene, oxygen and carbon monoxide in olefin as well as preparation and application of catalyst

Abstract

The invention belongs to the field of catalysts, and particularly relates to a catalyst for simultaneously removing acetylene, oxygen and carbon monoxide in olefin as well as preparation and application of the catalyst. The catalyst comprises the following components in percentage by mass: 30-50% of copper oxide, 10-50% of zinc oxide and 10-40% of aluminum oxide. The catalyst comprises the copper oxide, the zinc oxide and the aluminum oxide, all the components have a synergistic effect, and the compounded catalyst is used for removing trace acetylene, oxygen and carbon monoxide in olefin gases, has the characteristics of high adsorption capacity, high removal precision and long service life, can be repeatedly regenerated and used, and is simple in preparation process.

Description

Technical Field

[0001] The invention belongs to the field of catalysts, and in particular relates to a catalyst for simultaneously removing acetylene, oxygen and carbon monoxide from olefins, and the preparation and application of the catalyst. Background Art

[0002] Ethylene is an important chemical raw material, and its purity affects the quality of downstream products. At present, the main industrial processes for producing ethylene include petroleum hydrocarbon steam thermal cracking, catalytic cracking, and MTO, MTP, DMTO and other processes using methanol as raw material. In addition to the product ethylene, there are also a small amount of acetylene, water, carbon monoxide, oxygen and other impurities in the ethylene production process, which affect the deep processing of subsequent products. Therefore, it is very necessary to develop a catalyst that can remove multiple impurities at the same time.

[0003] There are two main types of deoxidizers. One is a hydrogenation deoxidation catalyst loaded with precious metals, the main active components of which are platinum and palladium. This type of deoxidizer has the characteristics of high activity and large deoxidation capacity, but it requires hydrogen replenishment, and new impurities such as hydrogen are easily introduced into the gas. The other type is an adsorption deoxidizer, which does not require hydrogen replenishment, but has a small oxygen capacity and requires regeneration and activation.

[0004] The deacetylation agent is mainly a hydrogenation deacetylation catalyst loaded with precious metals, and the main active components are platinum and palladium. This type of deacetylation agent has the characteristics of high deacetylation accuracy, but it is easy to produce green oil and deactivate the catalyst.

[0005] The carbon monoxide removal catalyst is mainly a catalytic oxidation catalyst, which has the advantages of low hydrogen consumption and low operating temperature, but has a high cost due to the high content of precious metals.

[0006] Therefore, in view of the shortcomings of existing deoxidizers, deacetylenes and carbon monoxide removal catalysts, the development of catalysts that can remove three impurities at the same time has broad market prospects. Summary of the invention

[0007] In order to overcome the deficiencies in the prior art, the object of the present invention is to provide a catalyst for simultaneously removing acetylene, oxygen and carbon monoxide from olefins, and its preparation and application.

[0008] To achieve the above purpose, the technical solution provided by the present invention is:

[0009] A catalyst for simultaneously removing acetylene, oxygen and carbon monoxide from olefins consists of the following components in percentage by mass: 30-50% copper oxide, 10-50% zinc oxide and 10-40% aluminum oxide.

[0010] Preferably, the catalyst is composed of the following components in percentage by mass: 30-47% copper oxide, 15-47% zinc oxide, and 18-38% aluminum oxide.

[0011] A method for preparing a catalyst comprises the following steps: adding copper salt and zinc salt to deionized water to dissolve them, adding an aluminum oxide precursor to obtain a mixed material, adding a precipitant to react and generate a precipitated product, filtering the precipitated product, washing, drying, and roasting to obtain a mixture of copper oxide, zinc oxide, and aluminum oxide, and pressing the mixture into tablets to obtain a catalyst.

[0012] The specific steps include:

[0013] (1) taking copper salt and zinc salt respectively, adding deionized water to dissolve, and then adding aluminum oxide precursor to stir to form a mixed material;

[0014] (2) heating the mixture prepared in step (1) to 70-80° C., stirring evenly, adding a precipitant, controlling the pH value of the system to 8-10, stirring for 1-6 hours, and generating a precipitated product;

[0015] (3) filtering the precipitated product of step (2), washing until neutral, drying at 80 to 120° C. for 5 to 12 hours, and then calcining at 300 to 500° C. in a nitrogen atmosphere for 5 to 12 hours to obtain a mixture containing copper oxide, zinc oxide and aluminum oxide;

[0016] (4) The mixture of step (3) is crushed and then pressed into tablets to obtain a catalyst for simultaneously removing acetylene, oxygen and carbon monoxide.

[0017] The copper salt in step (1) is one of copper nitrate, copper sulfate and copper chloride;

[0018] The zinc salt in step (1) is one of zinc nitrate, zinc sulfate and zinc chloride;

[0019] The alumina precursor in step (1) is one of pseudo-boehmite powder, activated alumina powder or aluminum nitrate.

[0020] The precipitant in step (2) is one of sodium hydroxide solution, potassium hydroxide solution and sodium carbonate solution, and the concentration of the precipitant solution is 2 mol / L.

[0021] A catalyst is used to simultaneously remove acetylene, oxygen and carbon monoxide from olefin gases.

[0022] The olefin gas is ethylene or propylene.

[0023] The conditions for removing acetylene, oxygen and carbon monoxide from olefins are: pressure 0.1-20 MPa, space velocity 1000-10000 h -1 , reaction temperature 80~120℃.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The catalyst of the present invention comprises copper oxide, zinc oxide and aluminum oxide, and the components act synergistically with each other. The composite catalyst is used to remove trace acetylene, oxygen and carbon monoxide in olefin gases, and has the characteristics of high adsorption capacity, high removal accuracy and long service life. It can be repeatedly regenerated and used, and the preparation process is simple. It can simultaneously remove trace oxygen, carbon monoxide and alkynes in olefin logistics, remove multiple impurities through a single fixed bed, greatly simplify the process flow, reduce equipment investment and floor space, reduce production costs, and has good industrial application prospects. DETAILED DESCRIPTION

[0026] The specific implementation modes of the present invention are further described below in conjunction with examples. It should be noted that the specific implementation modes described here are only for illustrating and explaining the present invention, and are not limited to the present invention.

[0027] Example 1

[0028] (1) Weigh 350 g of copper nitrate and 130.56 g of zinc nitrate respectively, add 400 g of deionized water to dissolve, add 135 g of pseudo-boehmite powder (with an aluminum oxide content of 66.7%), and stir thoroughly to prepare a mixed material;

[0029] (2) When the mixture prepared in step (1) is heated to 70° C., a 2 mol / L sodium carbonate aqueous solution is added dropwise while stirring until the pH value reaches 8.8, and stirring is continued at 70° C. for 2 hours to generate a precipitated product;

[0030] (3) filtering the precipitate from step (2), washing it to neutrality, drying it at 110° C. for 10 hours, and then calcining it at 500° C. in a nitrogen atmosphere for 5 hours to obtain a mixture containing copper oxide, zinc oxide and aluminum oxide;

[0031] (4) The mixture of step (3) is crushed, ground and sieved to obtain a powder of 200-300 mesh, and then pressed into tablets to obtain a catalyst containing 47% copper oxide, 15% zinc oxide and 38% aluminum oxide.

[0032] Example 2

[0033] (1) Weigh 120.74 g of copper nitrate and 141.25 g of zinc nitrate respectively, add 400 g of deionized water to dissolve, add 20 g of pseudo-boehmite powder (with an aluminum oxide content of 66.7%), and stir thoroughly to prepare a mixed material;

[0034] (2) When the mixture prepared in step (1) is heated to 70° C., a 2 mol / L sodium carbonate aqueous solution is added dropwise while stirring until the pH value reaches 8.8, and stirring is continued at 70° C. for 2 hours to generate a precipitated product;

[0035] (3) filtering the precipitate from step (2), washing it to neutrality, drying it at 110° C. for 10 hours, and then calcining it at 500° C. in a nitrogen atmosphere for 5 hours to obtain a mixture containing copper oxide, zinc oxide and aluminum oxide;

[0036] (4) The mixture of step (3) is crushed, ground and sieved to obtain a powder of 200-300 mesh, and then pressed into tablets to obtain a catalyst containing 43% copper oxide, 43% zinc oxide and 15% aluminum oxide.

[0037] Example 3

[0038] (1) Weigh 100.32 g of copper nitrate and 160.33 g of zinc nitrate respectively, add 400 g of deionized water to dissolve, add 25 g of pseudo-boehmite powder (with an aluminum oxide content of 66.7%), and stir thoroughly to prepare a mixed material;

[0039] (2) When the mixture prepared in step (1) is heated to 70° C., a 2 mol / L sodium carbonate aqueous solution is added dropwise while stirring until the pH value reaches 8.8, and stirring is continued at 70° C. for 2 hours to generate a precipitated product;

[0040] (3) filtering the precipitate from step (2), washing it to neutrality, drying it at 110° C. for 10 hours, and then calcining it at 500° C. in a nitrogen atmosphere for 5 hours to obtain a mixture containing copper oxide, zinc oxide and aluminum oxide;

[0041] (4) The mixture of step (3) is crushed, ground and sieved to obtain a powder of 200-300 mesh, and then pressed into tablets to obtain a catalyst containing 35% copper oxide, 47% zinc oxide and 18% aluminum oxide.

[0042] Comparative Example 1

[0043] (1) Weigh 30.22 g of copper nitrate and 160.33 g of zinc nitrate respectively, add 400 g of deionized water to dissolve, add 25 g of pseudo-boehmite powder (with an aluminum oxide content of 66.7%), and stir thoroughly to prepare a mixed material;

[0044] (2) When the mixture prepared in step (1) is heated to 70° C., a 2 mol / L sodium carbonate aqueous solution is added dropwise while stirring until the pH value reaches 8.8, and stirring is continued at 70° C. for 2 hours to generate a precipitated product;

[0045] (3) filtering the precipitate from step (2), washing it to neutrality, drying it at 110° C. for 10 hours, and then calcining it at 500° C. in a nitrogen atmosphere for 5 hours to obtain a mixture containing copper oxide, zinc oxide and aluminum oxide;

[0046] (4) The mixture of step (3) is crushed, ground and sieved to obtain a powder of 200-300 mesh, and then pressed into tablets to obtain a catalyst containing 14% copper oxide, 62% zinc oxide and 24% aluminum oxide.

[0047] Comparative Example 2

[0048] (1) Weigh 262 g of copper nitrate and 36.20 g of zinc nitrate respectively, add 600 g of deionized water to dissolve, add 10 g of pseudo-boehmite powder (with an aluminum oxide content of 66.7%), and stir thoroughly to prepare a mixed material;

[0049] (2) When the mixture prepared in step (1) is heated to 70° C., a 2 mol / L sodium carbonate aqueous solution is added dropwise while stirring until the pH value reaches 8.8, and stirring is continued at 70° C. for 2 hours to generate a precipitated product;

[0050] (3) filtering the precipitate from step (2), washing it to neutrality, drying it at 110° C. for 10 hours, and then calcining it at 500° C. in a nitrogen atmosphere for 5 hours to obtain a mixture containing copper oxide, zinc oxide and aluminum oxide;

[0051] (4) The mixture of step (3) is crushed, ground and sieved to obtain a powder of 200-300 mesh, and then pressed into tablets to obtain a catalyst containing 83% copper oxide, 10% zinc oxide and 7% aluminum oxide.

[0052] Comparative Example 3

[0053] (1) Weigh 110 g of copper nitrate, add 300 g of deionized water to dissolve, add 98 g of pseudo-boehmite powder (with an aluminum oxide content of 66.7%), and stir thoroughly to prepare a mixed material;

[0054] (2) When the mixture prepared in step (1) is heated to 70° C., a 2 mol / L sodium carbonate aqueous solution is added dropwise while stirring until the pH value reaches 8.8, and stirring is continued at 70° C. for 2 hours to generate a precipitated product;

[0055] (3) filtering the precipitate from step (2), washing it to neutrality, drying it at 110° C. for 10 hours, and then calcining it at 500° C. in a nitrogen atmosphere for 5 hours to obtain a mixture containing copper oxide and aluminum oxide;

[0056] (4) The mixture of step (3) is crushed, ground and sieved to obtain powder with a mesh size of 200-300, and then pressed into tablets to obtain a catalyst containing 35% copper oxide and 65% aluminum oxide.

[0057] Comparative Example 4

[0058] (1) Weigh 160.33 g of zinc nitrate, add 400 g of deionized water to dissolve, add 25 g of pseudo-boehmite powder (with an aluminum oxide content of 66.7%), and stir thoroughly to prepare a mixed material;

[0059] (2) When the mixture prepared in step (1) is heated to 70° C., a 2 mol / L sodium carbonate aqueous solution is added dropwise while stirring until the pH value reaches 8.8, and stirring is continued at 70° C. for 2 hours to generate a precipitated product;

[0060] (3) filtering the precipitate from step (2), washing it to neutrality, drying it at 110° C. for 10 hours, and then calcining it at 500° C. in a nitrogen atmosphere for 5 hours to obtain a mixture containing copper oxide, zinc oxide and aluminum oxide;

[0061] (4) The mixture of step (3) is crushed, ground and sieved to obtain powder with a mesh size of 200-300, and then pressed into tablets to obtain a catalyst containing 72% zinc oxide and 28% aluminum oxide.

[0062] Comparative Example 5

[0063] (1) Weigh 100.32 g of copper nitrate and 160.33 g of zinc nitrate respectively, add 400 g of deionized water to dissolve;

[0064] (2) When the temperature of the solution prepared in step (1) is raised to 70° C., a 2 mol / L sodium carbonate aqueous solution is added dropwise while stirring until the pH value reaches 8.8, and stirring is continued at 70° C. for 2 hours to generate a precipitated product;

[0065] (3) filtering the precipitate from step (2), washing it to neutrality, drying it at 110° C. for 10 hours, and then calcining it at 500° C. in a nitrogen atmosphere for 5 hours to obtain a mixture containing copper oxide, zinc oxide and aluminum oxide;

[0066] (4) The mixture of step (3) is crushed, ground and sieved to obtain a powder of 200-300 mesh, and then pressed into tablets to obtain a catalyst containing 42% copper oxide and 58% zinc oxide.

[0067] The samples prepared in the examples and comparative examples were subjected to an evaluation experiment for simultaneous removal of acetylene, carbon monoxide and oxygen. The experimental conditions were as follows: the catalyst was crushed and sieved to 20-30 meshes, 5 ml was taken and loaded into a stainless steel reactor with an inner diameter of 12 mm, and the reaction mixture was heated at a space velocity of 500 h -1 High-purity hydrogen was introduced for pre-reduction, and the reduction was carried out at 150-300°C for 6 hours. After the reduction was completed, high-purity nitrogen was introduced to replace the bed layer and cooled to room temperature. -1, 90℃, ethylene gas containing 50ppm acetylene, 50ppm carbon monoxide and 50ppm oxygen was introduced, and the outlet content was analyzed. When the outlet content of any of the above substances was first greater than 1ppm, the reaction was stopped and the removal capacity of each substance was calculated. The experimental results are shown in Table 1.

[0068] Table 1: Component content and acetylene, carbon monoxide and oxygen removal capacity of each sample

[0069]

[0070] As can be seen from Table 1, the content of each component in the catalyst has a significant effect on the adsorption capacity of the catalyst. The zinc oxide content of Comparative Example 1 is too high, and the copper oxide content of Comparative Example 2 is too high. The capacity of the corresponding catalyst to remove acetylene, carbon monoxide and oxygen is much lower than the adsorption capacity of Examples 1 to 3 of the present application, indicating that only the specific component content of the present application can achieve a good removal effect. In addition, Comparative Examples 3-5 are composed of only two components, but the removal capacity of acetylene, carbon monoxide and oxygen is also much lower than that of the embodiments. It can be seen that different components have a significant effect on the adsorption capacity of the catalyst. Therefore, the present invention selects specific components and contents, and copper oxide, zinc oxide and aluminum oxide work synergistically with each other to achieve the advantages of high adsorption capacity, high removal accuracy and long service life.

Claims

1. A catalyst for simultaneously removing acetylene, oxygen and carbon monoxide from olefins, characterized in that: The catalyst is composed of the following components in percentage by mass: 30-50% copper oxide, 10-50% zinc oxide and 10-40% aluminum oxide.

2. A method for preparing a catalyst according to claim 1, characterized in that: After copper salt and zinc salt are dissolved in deionized water, an aluminum oxide precursor is added to obtain a mixed material, a precipitant is added to react to generate a precipitated product, and the precipitated product is filtered, washed, dried, and roasted to obtain a mixture of copper oxide, zinc oxide, and aluminum oxide, which is pressed into tablets to form a catalyst.

3. The preparation method according to claim 2, characterized in that: The following steps are involved: (1) taking copper salt and zinc salt respectively, adding deionized water to dissolve, and then adding aluminum oxide precursor to stir to form a mixed material; (2) heating the mixture prepared in step (1) to 70-80° C., stirring evenly, adding a precipitant, controlling the pH value of the system to 8-10, stirring for 1-6 hours, and generating a precipitated product; (3) filtering the precipitated product of step (2), washing until neutral, drying at 80 to 120° C. for 5 to 12 hours, and then calcining at 300 to 500° C. in a nitrogen atmosphere for 5 to 12 hours to obtain a mixture containing copper oxide, zinc oxide and aluminum oxide; (4) The mixture of step (3) is crushed and then pressed into tablets to obtain a catalyst for simultaneously removing acetylene, oxygen and carbon monoxide.

4. The preparation method according to claim 3, characterized in that: The copper salt in step (1) is one of copper nitrate, copper sulfate and copper chloride; The zinc salt in step (1) is one of zinc nitrate, zinc sulfate and zinc chloride; The alumina precursor in step (1) is one of pseudo-boehmite powder, activated alumina powder or aluminum nitrate.

5. The preparation method according to claim 3, characterized in that: The precipitant in step (2) is one of sodium hydroxide solution, potassium hydroxide solution and sodium carbonate solution, and the concentration of the precipitant solution is 2 mol / L.

6. A catalyst as claimed in claim 1 for simultaneously removing acetylene, oxygen and carbon monoxide from olefin gas.

7. The use according to claim 6, characterized in that The olefin gas is ethylene or propylene.

8. The use according to claim 6, characterized in that The conditions for removing acetylene, oxygen and carbon monoxide from olefins are: pressure 0.1-20 MPa, space velocity 1000-10000 h -1 , reaction temperature 80~120℃.

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