Catalyst for the removal of o2 and no from olefin gas and method of making and using same x Catalyst for the removal of o2 and no from olefin gas and method of making and using same

Abstract

The application is a catalyst for removing O2 and NO from olefin gas and its preparation method and application. x The catalyst comprises an active component, an active adjuvant, a binder and a carrier; wherein: the active component is Ag and Ru bimetallic component; the active adjuvant is any one or mixture of both of Ba and Cs; the carrier is rare earth modified alumina; and the binder is pseudo-boehmite. The catalyst is applied to remove impurities O2 and NO from olefin gas in a refinery olefin purification process. x O2 in the olefin gas can be removed to less than 0.1 ppm at a low temperature of 100-160 DEG C, NO x is removed to ≤5 ppb, and the catalyst has good selectivity, the loss of olefin is less than 0.2%, and no reduction activation or sulfuration treatment is needed before use, which is convenient to use.

Description

Technical Field

[0001] This invention relates to the field of olefin gas purification processes in refineries, specifically to processes for removing O2 and NO from olefin gas. x Catalysts, their preparation methods, and applications. Background Technology

[0002] Ethylene and propylene are important chemical raw materials. Refinery catalytic cracking dry gas contains 15-50% hydrocarbon resources such as ethylene, propylene, methane, and ethane, which have high recovery and utilization value. Refinery catalytic cracking dry gas generally contains O2, CO2, CO, H2S, NH3, and NO. x Non-hydrocarbon harmful impurities such as NO and NO2 in the cracked gas can adversely affect the subsequent recovery and utilization of olefins. NO and NO2 in the cracked gas can react with O2 below -21°C to form liquid or solid N2O3, and with NH3 to form solid ammonium nitrate and ammonium nitrite. These substances are extremely unstable and pose an explosion hazard when heated or subjected to impact. Therefore, refinery dry gas recovery processes require that NO in olefins be... x The content should be below 10 ppb. In subsequent polyolefin industrial production, the presence of trace oxygen impurities can damage the active centers of highly efficient polyolefin catalysts or participate in the polymerization reaction, reducing catalyst activity and affecting product gas yield and quality. Therefore, olefin polymerization processes require that the oxygen content in ethylene and propylene be less than 1 ppm, and some processes with stringent requirements require an oxygen content of less than 0.1 ppm.

[0003] Currently, the most common deoxygenation methods used in industry are catalytic deoxygenation and chemical adsorption deoxygenation. Catalytic deoxygenation primarily uses noble metal deoxygenation catalysts, represented by Pd and Pt, and non-noble metal deoxygenation catalysts, represented by Cu, Mn, Ni, and Co. These catalysts have been widely applied to the purification of various high-purity gases, protective gases, and syngas. However, for olefin-rich gases such as catalytic cracking dry gas, especially under hydrogen-rich, high-pressure, and certain temperature conditions, with Pd, Pt, Cu, and Ni as active components, olefins readily undergo hydrogenation side reactions, resulting in significant ethylene losses.

[0004] Research on catalytic reduction catalysts for nitrogen oxides is primarily focused on environmental remediation of air pollution. The active components studied in these catalysts mainly include Pd, Pt, Ag, Cu, Mn, Ni, V, and W, such as those used for NO2 in automobile exhaust. x Purification treatment utilizes precious metals Pd and Pt. The denitrification catalyst for industrial exhaust gases is VW / Ti, but it is used for trace amounts of NO in olefin-containing gases. x There is limited research on removal.

[0005] Patent CN 101745391 A discloses a deoxidizer with Pd as the main active component and Ag, Au, Co, and Cr as co-active components, used for removing trace amounts of oxygen from catalytic cracking dry gas. Before use, it requires reduction activation with hydrogen at 100–550°C. This deoxidizer, with Pd as the main active component, is prone to hydrogenation side reactions during use, resulting in ethylene losses >1.0%.

[0006] US Patent 5340554 discloses a method for hydrocatalytic removal of nitrogen oxides (NOx) from refinery gas. x The method involves preparing a catalyst using sulfide-formed Ni and cobalt molybdate or iron / chromium oxide as the active components, and removing NO from refinery catalytic cracking dry gas under conditions of 150–190 °C and 0.8–1.1 MPa. x The removal rate is approximately 50%. This patented technology removes NO from refinery gas. x A sulfurized catalyst is used to prevent olefin loss, which is approximately 0.5%.

[0007] Patent CN 111068712 A discloses a catalyst for the simultaneous removal of oxygen and nitrogen oxides, using Pd as the active component and at least one auxiliary agent selected from Cu, Mn, Fe, Co, and Zn. This catalyst is used for deoxygenation and nitrogen oxide removal from dry gas from catalytic cracking in refineries. It requires pre-reduction treatment before use; after reduction, oxygen is removed to <1 ppm and NO is removed at 100-160°C. x <10ppb. This catalyst requires reduction treatment before use, and the use of Pd as the main active component makes it highly susceptible to olefin hydrogenation reactions, resulting in a significant loss of olefins.

[0008] Patent CN 102266788 A discloses a catalyst for removing oxygen and nitrogen oxides from hydrocarbon-containing gases and inert gases. It uses phosphorus-containing alumina as a support, and the active component is selected from at least one of Mo, W, and Cr, and at least one of Ni and Co. The catalyst needs to be sulfided before use. Under conditions where the feed gas contains less than 1000 ppm H2S and the reaction temperature is 120–260°C, it can remove oxygen to <1 ppm and NO. x <0.02ppm, olefin loss is less than 1%. The catalyst needs to be sulfided. The feed gas of the sulfided catalyst must contain H2S gas to maintain its activity and stability. Moreover, the operating temperature is high, the olefin loss is large, and the removal accuracy is not high.

[0009] The aforementioned patent discloses methods for removing O2 and NO from olefin-containing gases. xCatalysts all have certain drawbacks and limitations. Some operate at high temperatures, exceeding 200°C, which exacerbates olefin cracking and polymerization side reactions, resulting in excessive olefin losses. Others require pretreatment through reduction or sulfidation, have low removal precision, and cannot be used for the simultaneous deep removal of O2 and NO from olefin gases. x .

[0010] Ethylene is chemically reactive and readily undergoes side reactions at high temperatures, including catalytic hydrogenation to ethane, ethylene oligomerization, and coking. For olefin-rich gases such as catalytic cracking dry gas, especially under hydrogen-rich, high-pressure, and certain temperature conditions, olefins readily undergo catalytic hydrogenation. This necessitates catalysts with multiple functions and properties: low-temperature, highly selective catalytic removal of O2 and NO. x No olefin hydrogenation reaction occurs. Summary of the Invention

[0011] The purpose of this invention is to address the problems with the processes and catalysts mentioned in the background art by providing a method for removing O2 and NO from olefin gas in refineries. x This catalyst uses Ag and Ru bimetallic compounds as active components, with alkali and alkaline earth metals as promoters, rare earth-modified alumina as a support, and macroporous boehmite as a binder. This enhances the catalyst's ability to remove O2 and NO from olefin gases. x While maintaining low-temperature activity, selectivity, and stability, it can also reduce the loss of olefin gases.

[0012] To achieve the above-mentioned objectives, the specific technical solution of this invention is as follows:

[0013] Used for O2 and NO removal from olefins x The catalyst comprises an active component, an active promoter, a binder, and a support. The active component is an Ag / Ru bimetallic compound, accounting for 1.0–10.0% of the total catalyst mass; the active promoter is an alkali metal Cs and an alkaline earth metal Ba, accounting for 0.5–5.0% of the total catalyst mass; the support is rare earth modified alumina, accounting for 65–93.5% of the total catalyst mass; and the binder is boehmite, accounting for 5–20% of the total catalyst mass. The sum of the total mass percentages of all components is 100%.

[0014] Furthermore, the pseudoboehmite is a macroporous pseudoboehmite with an average pore size of 7–25 nm.

[0015] Furthermore, the rare earth modified alumina is an active alumina modified by oxides of rare earth metals Ce and Pr, wherein the rare earth oxides account for 2.0 to 15.0% of the mass of the modified carrier.

[0016] Furthermore, the precursors of the active components Ag and Ru are both selected from their nitrates; the precursors of the auxiliary agents Ba and Cs are both selected from their nitrates; and the precursors of the rare earth metals Ce and Pr are both selected from their nitrates.

[0017] In this catalyst, due to the use of Ag and Ru bimetallic components as active components, Ag exhibits excellent low-temperature deoxygenation activity. In the presence of H2, it can remove oxygen from olefins to <0.1 ppm at low temperatures of 80–160 °C without olefin loss. Ag also has catalytic reduction activity for NO. x The activity of the catalyst is enhanced by loading it with the noble metal Ru. The active sites of Ru atoms can promote the activation of hydrogen, and the bimetallic interaction has a synergistic effect on catalysis, effectively improving the catalyst's removal of O2 and NO. x Its low-temperature activity and selectivity allow for the simultaneous and deep removal of impurities O2 and NO from refinery catalytic cracking dry gas. x .

[0018] Adding the alkaline earth metal Ba to this catalyst can improve the catalyst's adsorption of NO. x This ability is beneficial for removing trace amounts of NO from olefin gases. x Reduced to less than 10 ppb. Adding alkali metal Cs as an auxiliary agent can adjust the acidity and alkalinity of the catalyst surface, reduce the occurrence of olefin oligomerization, reduce carbon accumulation on the catalyst surface, and extend the catalyst's service life.

[0019] In this catalyst, rare earth metals Ce and Pr are used to modify the active alumina support. Ce has a good oxygen storage capacity, which can effectively improve the deoxygenation activity of the catalyst. The addition of Pr can improve the structural performance of the catalyst, which is beneficial to the dispersion of the active metal components, effectively prevents the active metal from sintering and growing at high temperature, and ensures the thermal stability and activity of the catalyst.

[0020] Macroporous boehmite, as a binder, can improve catalyst strength, effectively enhance catalyst specific surface area and regulate pore size, improve the dispersibility of active components and additives loaded on the support surface, thereby improving catalyst activity.

[0021] As a preferred embodiment of this application, the preparation method of the catalyst for simultaneously removing impurity oxygen and nitrogen oxides from olefin gas in a refinery, as described above, includes the following steps:

[0022] (1) Prepare a rare earth metal salt solution; immerse the active alumina powder in the rare earth metal salt solution, remove and filter it after a period of time, dry it in an oven, and then calcine it in a muffle furnace to obtain rare earth modified alumina carrier powder.

[0023] (2) Dissolve the active component in deionized water to prepare an active component solution; dissolve the active additive in deionized water to prepare an active additive solution; mix the active component solution and the active additive solution to obtain a metal salt mixed solution; thoroughly stir and mix the modified alumina carrier powder and macroporous pseudoboehmite prepared in step (1), then add them to the metal salt mixed solution and continue stirring until uniform, then knead and extrude them in an extruder.

[0024] (3) The catalyst extruded in step (2) is placed in an oven to dry, and then calcined in a muffle furnace to obtain the catalyst.

[0025] As a preferred embodiment of this application, in the above-mentioned method for preparing a catalyst for simultaneously removing impurity oxygen and nitrogen oxides from olefin gas in a refinery, the impregnation in step (1) is at room temperature for 4-8 hours; the temperature in the oven is 100-200°C and the drying time is 4-10 hours; the calcination temperature in the muffle furnace is 300-600°C and the time is 4-6 hours.

[0026] As a preferred embodiment of this application, impurities O2 and NO are simultaneously removed from the above-mentioned olefin gas used in refineries. x In the preparation method of the catalyst, the mixing time in step (2) is 1 to 2 hours.

[0027] As a preferred embodiment of this application, impurities O2 and NO are simultaneously removed from the above-mentioned olefin gas used in refineries. x In the preparation method of the catalyst, the temperature in the oven in step (3) is 100-200℃ and the drying time is 4-10h; the calcination temperature in the muffle furnace is 300-500℃ and the time is 4-6h.

[0028] Another objective of this invention is to protect a method or combination thereof prepared according to the above method for simultaneously removing impurities O2 and NO from olefin gases in refineries. x The catalyst is used in the purification process of olefin gases in refineries to remove impurities O2 and NO. x At the same time, it is removed.

[0029] Furthermore, the catalyst is used for the removal of O2 and NO from olefin gases. x The reaction temperature was 100–160 °C, the pressure was atmospheric pressure to 4 MPa, and the space velocity was 1000–15000 h⁻¹. -1 .

[0030] The typical composition of olefin gases in refineries is as follows:

[0031]

[0032] Compared with existing technologies, the beneficial effects of this invention are:

[0033] (i) By utilizing the complementary functions between the two active components, the catalyst activity can be improved, resulting in highly efficient catalysis, while reducing the formation of byproducts.

[0034] (ii) The preparation method of modifying the support before loading the active component is adopted to improve the preparation activity and stability of the catalyst;

[0035] (III) Applying the catalyst to the removal of O2 and NO from olefin gases x It has high removal precision and low reaction temperature. It can simultaneously remove oxygen from olefin gas to less than 0.1 ppm and nitrogen oxides to ≤5 ppb at a low temperature of 100-160℃. It also has good catalyst selectivity, with olefin loss of less than 0.2%. No reduction activation or sulfidation treatment is required before use, making it convenient to use. Detailed Implementation

[0036] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.

[0037] Any feature disclosed in this specification (including the claims and abstract) may be replaced by other equivalent or similar features, unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is merely one example of a series of equivalent or similar features.

[0038] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0039] Comparative Example 1

[0040] Weigh 157.2g of activated alumina and 42.86g of macroporous pseudoboehmite (calcined alumina mass fraction is 70%), add them to a mixing tank and stir until homogeneous. Weigh 17.61g of silver nitrate and 1.91g of ruthenium nitrate and dissolve them in 112g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the mixing tank and knead for 1 hour. After kneading until homogeneous, extrude the mixture into strips with a diameter of 2mm, place them in an oven and dry at 120℃ for 8 hours. Then calcine them in a muffle furnace at 450℃ for 6 hours to obtain the finished catalyst, denoted as DON-1.

[0041] Example 1

[0042] 201.86g of cerium nitrate hexahydrate and 51.1g of praseodymium nitrate were weighed and dissolved in 860g of deionized water to prepare a mixed solution. Then, 900g of active Al2O3 powder was weighed and immersed in the solution. After stirring evenly, the mixture was adsorbed and impregnated at room temperature for 6 hours, dried in an oven at 150℃ for 6 hours, and then calcined in a muffle furnace at 550℃ for 6 hours to obtain the rare earth modified carrier raw powder, which is denoted as modified carrier ZC-1.

[0043] Example 2

[0044] Weigh 167.2g of the ZC-1 modified support and 28.57g of macroporous pseudoboehmite prepared in Example 1, add them to a kneading tank and stir to mix evenly. Weigh 17.61g of silver nitrate and 1.90g of ruthenium nitrate and dissolve them in 112g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the kneading tank and knead for 1 hour. After kneading evenly, extrude it into strips with a diameter of 2mm, place them in an oven and dry at 120℃ for 8 hours. Then calcine them in a muffle furnace at 450℃ for 6 hours to obtain the finished catalyst, which is designated as DON-2.

[0045] Example 3:

[0046] Weigh 167.60g of the ZC-1 modified support and 28.57g of macroporous pseudoboehmite prepared in Example 1, add them to a kneading tank and stir until homogeneous. Weigh 5.86g of silver nitrate, 0.95g of ruthenium nitrate and 15.35g of barium nitrate and dissolve them in 112g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the kneading tank and knead for 1 hour. After kneading until homogeneous, extrude the mixture into strips with a diameter of 2mm, place them in an oven and dry at 120℃ for 6 hours. Then calcine them in a muffle furnace at 450℃ for 6 hours to obtain the finished catalyst, denoted as DON-3.

[0047] Example 4:

[0048] Weigh 166.0 g of the ZC-1 modified support prepared in Example 1 and 42.86 g of macroporous pseudoboehmite, add them to a kneading tank and stir until homogeneous. Weigh 2.94 g of silver nitrate, 2.38 g of ruthenium nitrate and 1.38 g of cesium nitrate and dissolve them in 112 g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the kneading tank and knead for 1 h. After kneading until homogeneous, extrude the mixture into strips with a diameter of 2 mm, place them in an oven and dry at 120 °C for 6 h. Then calcine them in a muffle furnace at 450 °C for 6 h to obtain the finished catalyst, denoted as DON-4.

[0049] Example 5

[0050] Weigh 145.60g of the ZC-1 modified support and 57.14g of macroporous pseudoboehmite prepared in Example 1, add them to a kneading tank and stir until homogeneous. Weigh 11.74g of silver nitrate, 0.95g of ruthenium nitrate, 6.82g of barium nitrate and 2.76g of cesium nitrate and dissolve them in 112g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the kneading tank and knead for 1 hour. After kneading until homogeneous, extrude the mixture into strips with a diameter of 2mm, place them in an oven and dry at 120℃ for 6 hours. Then calcine them in a muffle furnace at 450℃ for 6 hours to obtain the finished catalyst, denoted as DON-5.

[0051] Example 6

[0052] 50.46g of cerium nitrate hexahydrate and 5.11g of praseodymium nitrate were weighed and dissolved in 176g of deionized water to prepare a mixed solution. Then, 188g of active Al2O3 powder was weighed and immersed in the solution. After stirring evenly, the mixture was adsorbed and impregnated at room temperature for 6 hours. Then, it was dried in an oven at 150℃ for 4 hours and calcined in a muffle furnace at 550℃ for 6 hours to obtain rare earth modified carrier powder. Weigh 160.0g of modified support and 42.86g of macroporous pseudoboehmite, add them to a mixing tank and stir until homogeneous. Weigh 2.93g of silver nitrate, 4.77g of ruthenium nitrate, 6.82g of barium nitrate, and 1.38g of cesium nitrate and dissolve them in 112g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the mixing tank and knead for 1 hour. After kneading until homogeneous, extrude the mixture into strips with a diameter of 2mm, place them in an oven and dry at 120℃ for 6 hours. Then calcine them in a muffle furnace at 450℃ for 6 hours to obtain the finished catalyst, designated DON-6.

[0053] Example 7

[0054] 50.46g of cerium nitrate hexahydrate and 5.11g of praseodymium nitrate were weighed and dissolved in 186g of deionized water to prepare a mixed solution. Then, 194g of active Al2O3 powder was weighed and immersed in the solution. After stirring evenly, the mixture was adsorbed and impregnated at room temperature for 4 hours, dried in an oven at 150℃ for 6 hours, and then calcined in a muffle furnace at 550℃ for 6 hours to obtain rare earth modified carrier powder. Weigh 146.0g of modified support and 42.86g of macroporous pseudoboehmite, add them to a mixing tank and stir until homogeneous. Weigh 25.0g of silver nitrate, 4.76g of ruthenium nitrate, 6.82g of barium nitrate, and 1.38g of cesium nitrate and dissolve them in 110g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the mixing tank and knead for 1 hour. After kneading until homogeneous, extrude the mixture into strips with a diameter of 2mm, place them in an oven and dry at 120℃ for 6 hours. Then calcine them in a muffle furnace at 450℃ for 6 hours to obtain the finished catalyst, designated DON-7.

[0055] Example 8

[0056] 100.90g of cerium nitrate hexahydrate and 25.55g of praseodymium nitrate were weighed and dissolved in 152g of deionized water to prepare a mixed solution. Then, 170g of active Al2O3 powder was weighed and immersed in the solution. After stirring evenly, the mixture was adsorbed and impregnated at room temperature for 4 hours, dried in an oven at 150℃ for 4 hours, and then calcined in a muffle furnace at 550℃ for 6 hours to obtain rare earth modified carrier powder. Weigh 163.8g of modified support and 37.14g of macroporous pseudoboehmite, add them to a mixing tank and stir until homogeneous. Weigh 11.74g of silver nitrate, 0.48g of ruthenium nitrate, 1.71g of barium nitrate, and 1.38g of cesium nitrate and dissolve them in 112g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the mixing tank and knead for 1 hour. After kneading until homogeneous, extrude the mixture into strips with a diameter of 2mm, place them in an oven and dry at 120℃ for 6 hours. Then calcine them in a muffle furnace at 450℃ for 6 hours to obtain the finished catalyst, designated DON-8.

[0057] Example 9

[0058] 50.46g of cerium nitrate hexahydrate and 10.2g of praseodymium nitrate were weighed and dissolved in 175g of deionized water to prepare a mixed solution. Then, 186g of active Al2O3 powder was weighed and immersed in the solution. After stirring evenly, the mixture was adsorbed and impregnated at room temperature for 4 hours, dried in an oven at 150℃ for 4 hours, and then calcined in a muffle furnace at 550℃ for 6 hours to obtain rare earth modified carrier powder. Weigh 176.60g of modified support and 14.29g of macroporous pseudoboehmite, add them to a mixing tank and stir until homogeneous. Weigh 14.68g of silver nitrate, 0.95g of ruthenium nitrate, 3.41g of barium nitrate, and 1.38g of cesium nitrate and dissolve them in 112g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the mixing tank and knead for 1 hour. After kneading until homogeneous, extrude the mixture into strips with a diameter of 2mm, place them in an oven, dry at 120℃ for 6 hours, and then calcine them in a muffle furnace at 450℃ for 6 hours to obtain the finished catalyst, designated DON-9.

[0059] Comparative Example 2

[0060] Weigh 153.40g of the ZC-1 modified support and 42.86g of macroporous pseudoboehmite prepared in Example 1, add them to a mixing tank and stir until homogeneous. Weigh 14.68g of silver nitrate, 0.95g of ruthenium nitrate, 6.82g of barium nitrate, and 2.76g of cesium nitrate. Take 20ml of palladium nitrate solution with a Pd content of 10mg / ml and dissolve it all in 92g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the mixing tank and knead for 1h. After kneading until homogeneous, extrude it into strips with a diameter of 2mm, place them in an oven and dry at 120℃ for 6h. Then calcine them in a muffle furnace at 450℃ for 6h to obtain the finished catalyst, denoted as DON-10.

[0061] Comparative Example 3

[0062] Weigh 153.40g of the ZC-1 modified support and 42.86g of macroporous pseudoboehmite prepared in Example 1, add them to a mixing tank and stir until homogeneous. Weigh 14.68g of silver nitrate, 0.95g of ruthenium nitrate, 6.82g of barium nitrate, and 2.76g of cesium nitrate. Take 20ml of platinum nitrate solution with a Pt content of 10mg / ml and dissolve it all in 92g of 2% nitric acid aqueous solution. Add the prepared mixed solution to the mixing tank and knead for 1h. After kneading until homogeneous, extrude it into strips with a diameter of 2mm, place them in an oven and dry at 120℃ for 6h. Then calcine them in a muffle furnace at 450℃ for 6h to obtain the finished catalyst, denoted as DON-11.

[0063] Comparative Example 4

[0064] Weigh 186.6g of the ZC-1 modified support prepared in Example 1 and add it to a kneading tank. Weigh 14.86g of silver nitrate, 0.95g of ruthenium nitrate, 3.41g of barium nitrate, and 1.38g of cesium nitrate and dissolve them in 105g of deionized water. Add the prepared mixed solution to the kneading tank and knead with the modified support for 1 hour. After kneading evenly, extrude it into strips with a diameter of 2mm, place them in an oven, dry them at 120℃ for 6 hours, and then calcine them in a muffle furnace at 450℃ for 6 hours to obtain the finished catalyst, which is designated as DON-12.

[0065] The catalysts obtained in Comparative Example 1, Comparative Example 4, and Examples 5 and 9 were subjected to BET characterization and mechanical strength tests, and the results are shown in Table 1.

[0066] Table 1. Results of BET characterization and strength tests

[0067]

[0068] The catalysts obtained in Comparative Examples 1, 4, 5, and 9 were evaluated for performance. Taking the removal of oxygen and nitrogen oxides from ethylene as an example, the composition of the feed gas is shown in Table 2. The catalyst loading was 15 mL, the reaction pressure was 2.0 MPa, and the space velocity was 8000 h⁻¹. -1 The evaluation results are shown in Table 3.

[0069] Table 2 Composition of Raw Gas

[0070] Components <![CDATA[C2H4]]> <![CDATA[CH4]]> <![CDATA[H2]]> <![CDATA[O2]]> <![CDATA[NO x ]]> <![CDATA[N2]]> Volume fraction 30.2％ 25.0％ 14.1％ 1990ppm 50ppm 30.5％

[0071] Table 3. Catalyst evaluation results for Comparative Examples 1-3 and Examples 2-9

[0072]

[0073] The embodiments described above merely illustrate specific implementation methods of this application, and while the descriptions are detailed and specific, they should not be construed as limiting the scope of protection of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the technical solution of this application, and these modifications and improvements all fall within the scope of protection of this application.

[0074] This background section is provided to generally present the context of the invention. The work of the currently named inventors, the work to the extent described in this background section, and aspects of this section that did not constitute prior art at the time of application are neither expressly nor impliedly acknowledged as prior art to the invention.

Claims

1. Used for O2 and NO removal from olefins. x The catalyst comprises an active component, an active additive, a binder, and a support; characterized in that: The active component is an Ag / Ru bimetallic component, accounting for 1.0~10.0% of the total mass of the catalyst; The active additive is any one or a mixture of two of Ba and Cs, accounting for 0.5-5.0% of the total mass of the catalyst; The support is rare earth modified alumina, accounting for 65-93.5% of the total mass of the catalyst; The binder is boehmite, accounting for 5-20% of the total mass of the catalyst; The sum of the total mass percentages of all components is 100%. The rare earth modified alumina is an active alumina modified by oxides of rare earth metals Ce and Pr, wherein the rare earth oxides account for 2.0~15.0% of the mass of the modified carrier; Used for O2 and NO removal from olefins x The method for preparing the catalyst includes the following steps: (1) Prepare a rare earth metal salt solution; immerse the active alumina powder in the rare earth metal salt solution, remove and filter it after a period of time, dry it in an oven, and then calcine it in a muffle furnace to obtain rare earth modified alumina carrier powder. (2) Dissolve the active component in deionized water to prepare an active component solution; dissolve the active additive in deionized water to prepare an active additive solution; mix the active component solution and the active additive solution to obtain a metal salt mixed solution; thoroughly stir and mix the modified alumina carrier powder and macroporous pseudoboehmite prepared in step (1), then add them to the metal salt mixed solution and continue stirring until uniform, then knead and extrude them in an extruder. (3) The catalyst extruded in step (2) is placed in an oven to dry, and then calcined in a muffle furnace to obtain the catalyst.

2. The method for removing O2 and NO from olefins according to claim 1 x The catalyst, characterized in that: The pseudoboehmite is a macroporous pseudoboehmite with an average pore size of 7~25nm.

3. The method for removing O2 and NO from olefins according to claim 1 x The catalyst, characterized in that: The precursors of the active components Ag and Ru are both selected from their nitrates; the precursors of the active auxiliaries Ba and Cs are both selected from their nitrates; and the precursors of the rare earth metals Ce and Pr are selected from their nitrates.

4. The method for removing O2 and NO from olefins according to claim 1 x The catalyst, characterized in that: The impregnation in step (1) is at room temperature for 4 to 8 hours; the temperature in the oven is 100 to 200°C and the drying time is 4 to 10 hours; the calcination temperature in the muffle furnace is 300 to 600°C and the time is 4 to 6 hours.

5. The method for removing O2 and NO from olefins according to claim 1 x The catalyst, characterized in that: The mixing time in step (2) is 1-2 hours.

6. The method for removing O2 and NO from olefins according to claim 1 x The catalyst, characterized in that: In step (3), the temperature in the oven is 100~200℃ and the drying time is 4h~10h; the calcination temperature in the muffle furnace is 300~500℃ and the time is 4~6h.

7. The method for removing O2 and NO from olefins according to any one of claims 1-6 x The catalyst, characterized in that: The catalyst is used to simultaneously remove O2 and NO from olefin gases in refineries. x .

8. The method for removing O2 and NO from olefins according to claim 7 x The catalyst, characterized in that: The catalyst is used to simultaneously remove O2 and NO from olefin gases in refineries. x The reaction temperature was 100–160 °C, the pressure was atmospheric pressure to 4 MPa, and the space velocity was 1000–15000 h⁻¹. -1 .

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