Purifying agents for removing CO and H2 from olefin disproportionation feedstocks, their preparation methods and applications

Abstract

This invention discloses a purification agent for removing CO and H2 from olefin disproportionation feedstock, its preparation method, and its application. The purification agent comprises a copper-based composite metal oxide and a silica molecular sieve. The component distribution coefficient D is defined as: D = (normalized weight content of the component measured by XRF) / (normalized weight content of the component measured by ICP), satisfying: DMO X The concentration is 0–0.8, and the concentration of DSiO2 is 1.8–5.0. This purifier is used in the process of removing CO and H2 from olefin disproportionation feedstock containing high-carbon olefins. It can selectively remove hydrogen and carbon monoxide from olefin disproportionation feedstock, and can also avoid the adsorption / reaction of small amounts of high-carbon olefins in the feedstock on the surface of the purifier, thus extending the service life of the purifier.

Description

Technical Field

[0001] This invention relates to the field of olefin feedstock purification, specifically to a purification agent for removing CO and H2 from olefin disproportionation feedstock and its preparation method, as well as its application in the purification of olefin disproportionation feedstock for the production of polymer-grade propylene. Background Technology

[0002] Olefin disproportionation is a process in which the C=C double bonds in olefins are broken and reformed under the action of a transition metal compound catalyst to obtain new olefin products.

[0003] By utilizing the cross-disproportionation effect of butene and ethylene, the relatively surplus and low-value-added C4 olefin feedstock can be converted into high-value-added propylene products by adding an appropriate amount of ethylene.

[0004] The olefin feedstock used in disproportionation reactions often comes from steam cracking or catalytic cracking units and contains small amounts of water, oxygen-containing compounds, and sulfur-containing compounds, among which the oxygen-containing compounds are mostly alcohols or ethers. These compounds can easily occupy the reactive sites of the disproportionation catalyst, thus causing catalyst poisoning. Therefore, the feedstock must be purified before it enters the bed to contact the disproportionation catalyst.

[0005] Currently used purification processes only target the removal of oxygen- and sulfur-containing compounds from olefin feedstocks, which is sufficient for conventional disproportionation reactions. However, olefin feedstocks also contain small amounts of hydrogen and carbon monoxide, which can affect the selectivity of olefin disproportionation reactions, reduce the yield of the target product, and cause additional material and energy consumption. Furthermore, if the hydrogen and carbon monoxide in the feedstock are not treated, they will also affect the quality of the propylene product, making it unusable as a raw material for polymerization-grade propylene and requiring secondary purification. Secondary purification requires an additional oxygen-containing compound removal unit, which prolongs the reaction process, increases investment, and is not conducive to the intensive configuration of production facilities.

[0006] CN114225959A discloses a catalyst for CO purification of olefin streams, its preparation method, and its application. The catalyst comprises a high-silica molecular sieve support, a cuprous component supported on the high-silica molecular sieve support, and an active additive.

[0007] CN101642707A discloses a two-component copper-zirconium catalyst for deep removal of carbon monoxide. The catalyst comprises: 0.1 wt% to 99.9 wt% of a main component CuO and 0.1 wt% to 99.9 wt% of a secondary component ZrO2.

[0008] The above-mentioned purifiers can remove CO and / or H2 from low-carbon olefins. However, when the olefin material contains high-carbon olefins, long-chain olefins are easily adsorbed and reacted on the surface of the purifier, which leads to the blockage and coverage of active sites, resulting in decreased activity and inability to maintain stability during long-term operation. Summary of the Invention

[0009] The technical problem this invention aims to solve is the poor activity and stability of olefin disproportionation feedstocks containing high-carbon olefins in the deep removal of hydrogen and carbon monoxide. This invention provides a purifying agent for removing CO and H2 from olefin disproportionation feedstocks, its preparation method, and its application. This purifying agent, when used for removing CO and H2 from olefin disproportionation feedstocks containing high-carbon olefins, can selectively remove hydrogen and carbon monoxide from the feedstock, and also avoids the adsorption / reaction of small amounts of high-carbon olefins on the surface of the purifying agent, thus extending the service life of the purifying agent.

[0010] The first aspect of this invention provides a purification agent for removing CO and H2 from olefin disproportionation feedstock, comprising a copper-based composite metal oxide and a silica molecular sieve. The component distribution coefficient D is defined as: D = normalized weight content of the component measured by XRF / normalized weight content of the component measured by ICP, satisfying: DMO X The concentration is 0–0.8, and the DSiO2 concentration is 1.8–5.0. Preferably, DMO... X The concentration is 0.2–0.7, and the concentration of DSiO2 is 2.5–4.5.

[0011] Furthermore, the copper-based composite metal oxide MO X MO in X DMO represents any metal oxide in copper-based composite metal oxides. X The values ​​of the component distribution coefficient D, which range from 0 to 0.8, represent the values ​​of any one of the metal oxides in the copper-based composite metal oxide. Each value is independently selected from 0 to 0.8.

[0012] Furthermore, the copper-based composite metal oxide includes copper oxide (CuO), cerium oxide (CeO2), and zirconium oxide (ZrO2).

[0013] Further, preferably, in the purifying agent, DCuO = 0.2-0.6, DCeO2 = 0.3-0.7, and DZrO2 = 0.3-0.8.

[0014] Furthermore, in the purifying agent, a silica molecular sieve is coated on the outer surface of the purifying agent, and the silica molecular sieve is a pure silica molecular sieve.

[0015] Further, the purifying agent preferably comprises, by weight parts: 100 parts copper oxide, 10-60 parts cerium oxide, 15-60 parts zirconium oxide, and 20-80 parts silicon oxide; more preferably, it comprises: 100 parts copper oxide, 20-55 parts cerium oxide, 18-50 parts zirconium oxide, and 30-60 parts silicon oxide.

[0016] Furthermore, the pure silica molecular sieve is at least one of Silicalite-1 and MCM-41.

[0017] A second aspect of the present invention provides a method for preparing the above-mentioned purifying agent, comprising:

[0018] (1) Prepare copper-based composite metal oxide particles as the core.

[0019] (2) The kernel from step (1) is mixed with water, silicon source and template agent, and then subjected to hydrothermal crystallization, drying and calcination to obtain the purifying agent.

[0020] Furthermore, the copper-based composite metal oxide in step (1) can be prepared by precipitation, impregnation, citric acid combustion, or other techniques well known in the art. The copper-containing composite metal oxide particles can be obtained as small particles of 20-100 mesh by pressing and sieving.

[0021] Further, in step (1), the copper-based composite metal oxide is preferably prepared by a co-current precipitation method, including: co-current precipitation of a metal salt solution and a precipitant alkaline solution under ultrasonic conditions, followed by solid-liquid separation, drying, and calcination to obtain the copper-based composite metal oxide. In the metal salt solution, the copper source, cerium source, and zirconium source can be soluble salts, such as nitrates. The alkali in the precipitant is sodium carbonate and sodium hydroxide, wherein the mass ratio of sodium carbonate to sodium hydroxide is 0.2–5.0. The ultrasonic conditions are as follows: 30–50 Hz, 0.2–1.0 kW. The precipitation conditions are as follows: temperature 40–70℃, pH 7–9, co-current time 0.5–2 hours. The drying conditions are: drying temperature 100–130℃, drying time 8–36 hours; calcination conditions are: calcination temperature 250–650℃, calcination time 2–12 hours.

[0022] Further, the hydrothermal crystallization conditions in step (2) are as follows: the crystallization temperature is 120-180℃, and the crystallization time is 4-72 hours, preferably 24-72 hours.

[0023] Further, the silicon source in step (2) is selected from at least one of silica sol or tetraethyl silicate; the template agent is tetrapropylammonium hydroxide or hexadecyltrimethylammonium bromide.

[0024] Furthermore, in step (2), the material ratio of water, silicon source (calculated as SiO2), and template agent (R) is H2O:SiO2:R = 20~300:2~10:1.

[0025] Further, the drying conditions described in step (2) are: drying temperature of 100-130℃, drying time of 8-36 hours, preferably 12-24 hours; and calcination conditions are: calcination temperature of 250-650℃, calcination time of 2-12 hours, preferably calcination temperature of 450-550℃, and calcination time of 3-6 hours.

[0026] Furthermore, after crystallization in step (2), the product can be dried after conventional steps such as filtration and washing.

[0027] A third aspect of the present invention provides the application of the above-mentioned purifying agent in removing carbon monoxide and hydrogen from olefin disproportionation feedstock.

[0028] Furthermore, the purifying agent is reduced before use; the reduction conditions are as follows: temperature 60–200°C, reducing gas is hydrogen-containing gas, and the volume hourly space velocity of the reducing gas is 100–1000 h⁻¹. -1 The hydrogen-containing gas can be a mixture of hydrogen and nitrogen, wherein hydrogen accounts for 1% to 5% by volume. Preferably, the reduction conditions are: a temperature of 80 to 180°C and a volume hourly space velocity (VHSV) of 200 to 800 h⁻¹. -1 .

[0029] Furthermore, in the olefin disproportionation feedstock, the hydrogen concentration is 1 ppm to 2000 ppm and the carbon monoxide concentration is 1 ppm to 2000 ppm by mass; further, the hydrogen concentration is 5 ppm to 2000 ppm and the carbon monoxide concentration is 2 ppm to 2000 ppm by mass.

[0030] Furthermore, the olefins in the olefin disproportionation feedstock are ethylene and butene, with a concentration of 50.0% to 99.9% by mass.

[0031] Furthermore, the olefin disproportionation feedstock also contains high-carbon olefins, i.e. olefins with more than five carbon atoms, including five-, six-, and seven-carbon olefins, especially five- and six-carbon olefins, with a concentration of 20 ppm to 2000 ppm by mass.

[0032] Furthermore, the olefin disproportionation feedstock also contains one or more of the following gases: an inert gas, an alkane with no more than 6 carbon atoms, and an alkyne with no more than 6 carbon atoms. Preferably, the alkane with no more than 6 carbon atoms is at least one of methane, ethane, propane, butane, pentane, and hexane. Preferably, the inert gas is nitrogen, argon, or helium.

[0033] Furthermore, the application employs a fixed-bed adsorption method, in which the purifying agent is filled into a purification tower, and the olefin disproportionation feedstock is introduced into the purification tower to contact with the purifying agent for purification, thereby obtaining purified olefin disproportionation feedstock.

[0034] Furthermore, the purification conditions are as follows: the gas hourly space velocity (VHSV) of the stream to be purified is 1000–20000 h⁻¹. -1 The bed temperature of the purification tower is 20-150℃, preferably 40-120℃, and the pressure of the purification tower is 0.1MPa-6MPa.

[0035] Furthermore, the purifying agent can be regenerated on-site at a temperature of 80–180°C, and the reducing gas is a hydrogen-containing gas with a volume hourly space velocity (VHSV) of 200–800 h⁻¹. -1 The hydrogen-containing gas can be a mixture of hydrogen and nitrogen, with hydrogen accounting for 1% to 5% by volume.

[0036] Compared with the prior art, the present invention has the following advantages:

[0037] (1) The purifier of the present invention has a core-shell structure, wherein the copper-based metal oxide is the core and the pure silicon molecular sieve is the shell. On the one hand, it can avoid high carbon olefins and other substances from covering the surface of copper-containing metal oxides, which would cause the active sites to be covered and affect the long-term performance and improve the stability of use. On the other hand, the use of pure silicon molecular sieve as the shell has a three-dimensional pore structure that can ensure that small molecules contact the active sites. At the same time, its diffusion resistance to high carbon olefins can prevent olefins from covering the active sites of oxides.

[0038] (2) The preparation method of the purifier of the present invention has a short preparation process. By synthesizing a core-shell structure, a shell is constructed to prevent high carbon olefins from contacting the active sites of oxides, thus achieving the predetermined goal.

[0039] (3) The purification agent of the present invention can remove carbon monoxide and hydrogen from olefin disproportionation feedstock in a single purification tower.

[0040] (4) The purification agent of the present invention removes carbon monoxide and hydrogen from olefin disproportionation feedstock, which can improve the selectivity of disproportionation reaction and reduce the adsorption reaction units for further removal of oxygen-containing compounds.

[0041] (5) When the olefin disproportionation feedstock contains a small amount of high carbon (carbon number greater than or equal to 5) olefins, the purifier of the present invention can avoid the surface and internal pores being covered and blocked due to adsorption / reaction on the surface of the purifier, so that the performance of the purifier can be maintained for a longer time and the purification efficiency of long-term operation can be improved. Attached Figure Description

[0042] Figure 1The image shows the XRD pattern of the purifying agent obtained in Example 1 of this invention. Detailed Implementation

[0043] The technical solution of the present invention will be described in detail below with reference to the embodiments.

[0044] In this invention, ICP (Inductively Coupled Plasma Spectrometer) was used to determine the bulk oxide content of the purifying agent and contrast agent on an iCAP 6300 Duo spectrometer.

[0045] In this invention, XRF (X-ray Fluorescence) analysis is performed on an SRS3400 X-ray fluorescence spectrometer to analyze the (surface) oxide content of the purifying agent and contrast agent.

[0046] In this invention, powder X-ray diffraction (XRD) was performed using a Bruker-AXS D8 Advanced X-ray diffractometer with a Cu target Kα line and a Ni filter, at a tube voltage of 40 kV and a tube current of 250 mA, with a scanning range of 5-80°.

[0047]

Example 1

[0048] Synthetic copper-based purifier:

[0049] (1) Under ultrasonic conditions (50 Hz, 0.5 kW), a mixed salt solution containing 24.30 g Cu(NO3)2·3H2O, 4.04 g Ce(NO3)3·6H2O, and 9.76 g Zr(NO3)4·5H2O was co-currently precipitated with an alkaline solution containing 19.19 g Na2CO3. The conditions were: temperature 60℃, pH 8.5, and co-current time 0.5 h. The resulting precipitate was filtered, washed, and the filter cake was dried at 130℃ for 10 h; then calcined at 350℃ for 4 h to obtain a composite metal oxide. This composite oxide was then pressed into tablets and sieved into small particles of 20–60 mesh.

[0050] (2) Small particles of composite metal oxide were used as the core and placed in a mixed synthesis solution containing 180.0 g of water, 13.89 g of tetraethyl silicate, and 5.32 g of tetrapropylammonium hydroxide (25 wt%). The mixture was stirred at 30 °C for 20 hours, hydrothermally crystallized at 110 °C for 24 hours, filtered, and the filter cake was washed with deionized water until the pH reached 7. The filter cake was dried at 120 °C for 12 hours and calcined at 450 °C for 3 hours to obtain a copper-based purifier with a core-shell structure, wherein the core is CuCeZr oxide and the outer shell is Silicalite-1 molecular sieve. The elemental analysis data of the purifier are shown in Table 1.

[0051] The XRD pattern of the purifier is shown below. Figure 1 ,Depend on Figure 1 It can be seen that, due to the penetrating power of X-rays, diffraction peaks of both the inner core CuCeZr oxide and the outer shell Silicalite-1 molecular sieve are present in the spectrum.

[0052] The purifying agent is reduced before use, with the following conditions: temperature 140℃; reducing gas 5% hydrogen / nitrogen mixture; reducing gas volume hourly space velocity (VHSV) 200 h⁻¹. -1 .

[0053] The olefin disproportionation feedstock, by molar weight, contains 60% ethylene, 30% butene, 8% methane, 150 ppm hydrogen, 30 ppm carbon monoxide, 200 ppm hexene-3, and the remainder is nitrogen. The gas hourly space velocity (VHSV) of the feedstock to be purified is 8000 h⁻¹. -1 The bed temperature of the purification tower is 100℃; the pressure of the purification tower is 3.0MPa.

[0054] The performance of the purifier after 50 days of operation is shown in Table 2.

[0055] Comparative Example 1

[0056] Synthetic copper-based purifier:

[0057] (1) Under ultrasonic conditions (50 Hz, 0.5 kW), a mixed salt solution containing 24.30 g Cu(NO3)2·3H2O, 4.04 g Ce(NO3)3·6H2O, and 9.76 g Zr(NO3)4·5H2O was co-precipitated with an alkaline solution containing 19.19 g Na2CO3. The conditions were: temperature 60℃, pH 8.5, and co-precipitation time 0.5 h. The resulting precipitate was filtered, washed, and the filter cake was dried at 130℃ for 10 h; then calcined at 350℃ for 4 h to obtain a composite metal oxide. This composite oxide was then pressed into tablets and sieved into small particles of 20–60 mesh.

[0058] (2) Using composite metal oxide particles as the core, the mixture was placed in a synthetic solution containing 180.0 g of water and 13.89 g of tetraethyl silicate. The mixture was stirred at 30°C for 20 hours, then hydrothermally crystallized at 110°C for 24 hours. After filtration, the filter cake was washed with deionized water until the pH reached 7. The filter cake was then dried at 120°C for 12 hours and calcined at 450°C for 3 hours to obtain a copper-based purifier with a core-shell structure. Elemental analysis data of the purifier are shown in Table 1.

[0059] The purifying agent is reduced before use, with the following conditions: temperature 140℃; reducing gas 5% hydrogen / nitrogen mixture; reducing gas volume hourly space velocity (VHSV) 200 h⁻¹. -1 .

[0060] The olefin disproportionation feedstock, by molar weight, contains 60% ethylene, 30% butene, 8% methane, 150 ppm hydrogen, 30 ppm carbon monoxide, 200 ppm hexene-3, and the remainder is nitrogen. The gas hourly space velocity (VHSV) of the feedstock to be purified is 8000 h⁻¹. -1 The bed temperature of the purification tower is 100℃; the pressure of the purification tower is 3.0MPa.

[0061] The performance of the purifier after 50 days of operation is shown in Table 2.

[0062] Comparative Example 2

[0063] Synthetic copper-based purifier:

[0064] Under ultrasonic conditions (50 Hz, 0.5 kW), a mixed salt solution containing 24.30 g Cu(NO3)2·3H2O, 4.04 g Ce(NO3)3·6H2O, and 9.76 g Zr(NO3)4·5H2O was co-precipitated with an alkaline solution containing 19.19 g Na2CO3. The conditions were: temperature 60℃, pH 8.5, and co-current time 0.5 h. The resulting precipitate was filtered, washed, and the filter cake was dried at 130℃ for 10 h; then calcined at 350℃ for 4 h to obtain a composite metal oxide. This was then tableted and sieved into small particles of 20–60 mesh.

[0065] The purifying agent is reduced before use, with the following conditions: temperature 140℃; reducing gas 5% hydrogen / nitrogen mixture; reducing gas volume hourly space velocity (VHSV) 200 h⁻¹. -1 .

[0066] The olefin disproportionation feedstock, by molar weight, contains 60% ethylene, 30% butene, 8% methane, 150 ppm hydrogen, 30 ppm carbon monoxide, 200 ppm hexene-3, and the remainder is nitrogen. The gas hourly space velocity (VHSV) of the feedstock to be purified is 8000 h⁻¹. -1 The bed temperature of the purification tower is 100℃; the pressure of the purification tower is 3.0MPa.

[0067] The performance of the purifier after 50 days of operation is shown in Table 2.

[0068] Comparative Example 3

[0069] Synthetic copper-based purifier:

[0070] (1) A mixed synthesis solution containing 180.0 g of water, 13.89 g of tetraethyl silicate and 5.32 g of tetrapropylammonium hydroxide with a content of 25 wt% was prepared; the mixture was stirred at 30 °C for 20 hours, hydrothermally crystallized at 110 °C for 24 hours, filtered, the filter cake was washed with deionized water until the pH was 7, the filter cake was dried at 120 °C for 12 hours, and calcined at 450 °C for 3 hours to obtain Silicalite-1 molecular sieve.

[0071] (2) Under ultrasonic conditions (50 Hz, 0.5 kW), S1 molecular sieve was used to co-precipitate a mixed salt solution containing 24.30 g Cu(NO3)2·3H2O, 4.04 g Ce(NO3)3·6H2O, and 9.76 g Zr(NO3)4·5H2O in a co-current flow with an alkaline solution containing 19.19 g Na2CO3. The conditions were: temperature 60℃, pH 8.5, and co-current flow time 0.5 h. The resulting precipitate was filtered, washed, and the filter cake was dried at 130℃ for 10 h. The copper-based purifier was then calcined at 350℃ for 4 h. The elemental analysis data of the purifier are shown in Table 1.

[0072] The purifying agent is reduced before use, with the following conditions: temperature 140℃; reducing gas 5% hydrogen / nitrogen mixture; reducing gas volume hourly space velocity (VHSV) 200 h⁻¹. -1 .

[0073] The olefin disproportionation feedstock, by molar weight, contains 60% ethylene, 30% butene, 8% methane, 150 ppm hydrogen, 30 ppm carbon monoxide, 200 ppm hexene-3, and the remainder is nitrogen. The gas hourly space velocity (VHSV) of the feedstock to be purified is 8000 h⁻¹. -1 The bed temperature of the purification tower is 100℃; the pressure of the purification tower is 3.0MPa.

[0074] The performance of the purifier after 50 days of operation is shown in Table 2.

[0075] Comparative Example 4

[0076] Synthetic copper-based purifier:

[0077] (1) Under ultrasonic conditions (50 Hz, 0.5 kW), a mixed salt solution containing 24.30 g Cu(NO3)2·3H2O, 4.04 g Ce(NO3)3·6H2O, and 9.76 g Zr(NO3)4·5H2O was co-currently precipitated with an alkaline solution containing 19.19 g Na2CO3. The conditions were: temperature 60℃, pH 8.5, and co-current time 0.5 h. The resulting precipitate was filtered, washed, and the filter cake was dried at 130℃ for 10 h; then calcined at 350℃ for 4 h to obtain a composite metal oxide. This composite oxide was then pressed into tablets and sieved into small particles of 20–60 mesh.

[0078] (2) Using composite metal oxide particles as the core, the mixture was placed in a synthetic solution containing 360.0 g of water, 43.05 g of tetraethyl silicate, and 16.55 g of tetrapropylammonium hydroxide (25 wt%). The mixture was stirred at 30°C for 20 hours, then hydrothermally crystallized at 110°C for 24 hours. After filtration, the filter cake was washed with deionized water until the pH reached 7. The filter cake was then dried at 120°C for 12 hours and calcined at 450°C for 3 hours to obtain a copper-based purifier with a core-shell structure. Elemental analysis data of the purifier are shown in Table 1.

[0079] The purifying agent is reduced before use, with the following conditions: temperature 140℃; reducing gas 5% hydrogen / nitrogen mixture; reducing gas volume hourly space velocity (VHSV) 200 h⁻¹. -1 .

[0080] The olefin disproportionation feedstock, by molar weight, contains 60% ethylene, 30% butene, 8% methane, 150 ppm hydrogen, 30 ppm carbon monoxide, 200 ppm hexene-3, and the remainder is nitrogen. The gas hourly space velocity (VHSV) of the feedstock to be purified is 8000 h⁻¹. -1 The bed temperature of the purification tower is 100℃; the pressure of the purification tower is 3.0MPa.

[0081] The performance of the purifier after 50 days of operation is shown in Table 2.

[0082]

Example 2

[0083] Synthetic copper-based purifier:

[0084] (1) Under ultrasonic conditions (50 Hz, 0.5 kW), a mixed salt solution containing 24.30 g Cu(NO3)2·3H2O, 8.07 g Ce(NO3)3·6H2O, and 5.57 g Zr(NO3)4·5H2O was co-currently precipitated with an alkaline solution containing 19.09 g Na2CO3. The conditions were: temperature 50℃, pH 8.0, and co-current time 0.5 h. The resulting precipitate was filtered, washed, and the filter cake was dried at 100℃ for 12 h; then calcined at 350℃ for 3 h to obtain a composite metal oxide. This composite oxide was then tableted and sieved into small particles of 20–60 mesh.

[0085] (2) Small particles of composite metal oxide were used as the core and placed in a mixed synthesis solution containing 96.0 g of water, 8.33 g of tetraethyl silicate, and 3.31 g of tetrapropylammonium hydroxide (25 wt%). The mixture was stirred at 30 °C for 20 hours, hydrothermally crystallized at 110 °C for 24 hours, filtered, and the filter cake was washed with deionized water until the pH reached 7. The filter cake was dried at 120 °C for 12 hours and calcined at 450 °C for 3 hours to obtain a copper-based purifier with a core-shell structure, wherein the core is CuCeZr oxide and the outer shell is Silicalite-1 molecular sieve. The elemental analysis data of the purifier are shown in Table 1.

[0086] The purifying agent is reduced before use, with the following conditions: temperature 140℃; reducing gas 5% hydrogen / nitrogen mixture; reducing gas volume hourly space velocity (VHSV) 200 h⁻¹. -1 .

[0087] The olefin disproportionation feedstock, by molar weight, contains 60% ethylene, 30% butene, 8% methane, 150 ppm hydrogen, 30 ppm carbon monoxide, 200 ppm hexene-3, and the remainder is nitrogen. The gas hourly space velocity (VHSV) of the feedstock to be purified is 8000 h⁻¹. -1 The bed temperature of the purification tower is 100℃; the pressure of the purification tower is 3.0MPa.

[0088] The performance of the purifier after 50 days of operation is shown in Table 2.

[0089]

Example 3

[0090] Synthetic copper-based purifier:

[0091] (1) Under ultrasonic conditions (50 Hz, 0.5 kW), a mixed salt solution containing 24.30 g Cu(NO3)2·3H2O, 6.05 g Ce(NO3)3·6H2O, and 8.36 g Zr(NO3)4·5H2O was co-currently precipitated with an alkaline solution containing 19.52 g Na2CO3. The conditions were: temperature 50℃, pH 8.0, and co-current time 0.5 h. The precipitate was filtered, washed, and the filter cake was dried at 100℃ for 12 h; then calcined at 350℃ for 3 h to obtain a composite metal oxide. This composite oxide was then compressed into tablets and sieved into small particles of 20–60 mesh.

[0092] (2) Using composite metal oxide particles as the core, a mixed synthesis solution containing 200.0 g water, 12.50 g tetraethyl silicate, 1.43 g cetyltrimethylammonium bromide, and 43.2 g 25% ammonia was prepared. The solution was stirred at 30°C for 20 hours, hydrothermally crystallized at 110°C for 12 hours, filtered, and the filter cake was washed with deionized water until the pH reached 7. The filter cake was then dried at 120°C for 12 hours and calcined at 450°C for 3 hours to obtain a copper-based purifier with a core-shell structure, wherein the core is CuCeZr oxide and the outer shell is MCM-41 molecular sieve. The elemental analysis data of the purifier are shown in Table 1.

[0093] The purifying agent is reduced before use, with the following conditions: temperature 140℃; reducing gas 5% hydrogen / nitrogen mixture; reducing gas volume hourly space velocity (VHSV) 200 h⁻¹. -1 .

[0094] The olefin disproportionation feedstock, by molar weight, contains 60% ethylene, 30% butene, 8% methane, 150 ppm hydrogen, 30 ppm carbon monoxide, 200 ppm hexene-3, and the remainder is nitrogen. The gas hourly space velocity (VHSV) of the feedstock to be purified is 8000 h⁻¹. -1 The bed temperature of the purification tower is 100℃; the pressure of the purification tower is 3.0MPa.

[0095] The performance of the purifier after 50 days of operation is shown in Table 2.

[0096] Table 1

[0097]

[0098]

[0099] Continued from Table 1

[0100] DCuO <![CDATA[DCeO2]]> <![CDATA[DZrO2]]> <![CDATA[DSiO2]]> Example 1 0.24 0.39 0.37 3.49 Example 2 0.31 0.52 0.53 3.93 Example 3 0.51 0.45 0.69 2.73 Comparative Example 1 0.68 0.73 0.73 2.11 Comparative Example 2 1.02 1.00 0.94 - Comparative Example 3 1.18 1.83 1.10 0.21 Comparative Example 4 0.59 0.54 0.60 1.39

[0101] Table 2

[0102]

[0103]

[0104] The specific embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combining the various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A purification agent for removing CO and H2 from olefin disproportionation feedstock, characterized in that, The purifying agent is of core-shell structure, the copper-based composite metal oxide is the inner core and the silica molecular sieve is the outer shell. The component distribution coefficient D is defined as: D = the normalized weight content of the component obtained according to XRF measurement / the normalized weight content of the component obtained according to ICP measurement, and satisfies: DMO X 0.2-0.8, DSiO2 1.8-5.0, wherein MO X represents any one of the metal oxides in the copper-based composite metal oxide.

2. The purifying agent according to claim 1, characterized in that, DMO X The concentration is 0.2~0.7, and the concentration of DSiO2 is 2.5~4.

5.

3. The purifying agent according to claim 1, characterized in that, The copper-based composite metal oxide includes copper oxide, cerium oxide, and zirconium oxide.

4. The purifying agent according to claim 1, characterized in that, The silica molecular sieve is at least one of Silicalite-1 and MCM-41.

5. The purifying agent according to claim 3, characterized in that, In the purifying agent, DCuO=0.2~0.6, DCeO2=0.3~0.7, and DZrO2=0.3~0.

8.

6. The purifying agent according to claim 1, characterized in that, The purifying agent comprises, by weight, 100 parts copper oxide, 10-60 parts cerium oxide, 15-60 parts zirconium oxide, and 20-80 parts silicon oxide.

7. The purifying agent according to claim 6, characterized in that, The purifying agent comprises, by weight, 100 parts copper oxide, 20-55 parts cerium oxide, 18-50 parts zirconium oxide, and 30-60 parts silicon oxide.

8. A method for preparing the purifying agent according to any one of claims 1-7, comprising: (1) Preparation of copper-based composite metal oxide particles as the core, (2) The kernel from step (1) is mixed with water, silicon source and template agent, and then subjected to hydrothermal crystallization, drying and calcination to obtain the purifying agent.

9. The preparation method according to claim 8, characterized in that, In step (1), the copper-based composite metal oxide is prepared by co-current precipitation.

10. The preparation method according to claim 8, characterized in that, The hydrothermal crystallization conditions described in step (2) are as follows: crystallization temperature is 120~180 ℃, and crystallization time is 4~72 hours.

11. The preparation method according to claim 8, characterized in that, The silicon source in step (2) is selected from at least one of silica sol or tetraethyl silicate, and the template agent is tetrapropylammonium hydroxide or hexadecyltrimethylammonium bromide.

12. The preparation method according to claim 8, characterized in that, In step (2), the material ratio of water, silicon source (calculated as SiO2), and template agent (R) is H2O: SiO2:R = 20~300:2~10:

1.

13. The preparation method according to claim 10, characterized in that, The crystallization time in step (2) is 24 to 72 hours.

14. The preparation method according to claim 8, characterized in that, The drying conditions described in step (2) are: drying temperature of 100~130 ℃ and drying time of 8~36 hours; and the calcination conditions are: calcination temperature of 250~650 ℃ and calcination time of 2~12 hours.

15. The preparation method according to claim 14, characterized in that, The drying conditions described in step (2) are: drying time of 12 to 24 hours and calcination conditions: calcination temperature of 450 to 550 ℃ and calcination time of 3 to 6 hours.

16. The use of the purifying agent according to any one of claims 1-7 or the purifying agent obtained by any one of the preparation methods of claims 8-15 in removing carbon monoxide and hydrogen from olefin disproportionation feedstock.

17. The application according to claim 16, characterized in that, The olefin disproportionation feedstock has a hydrogen concentration of 1 ppm to 2000 ppm and a carbon monoxide concentration of 1 ppm to 2000 ppm by mass.

18. The application according to claim 17, characterized in that, The olefin disproportionation feedstock has a hydrogen concentration of 5 ppm to 2000 ppm and a carbon monoxide concentration of 2 ppm to 2000 ppm by mass.

19. The application according to claim 17, characterized in that, The olefin disproportionation feedstock also contains high-carbon olefins, i.e. olefins with more than five carbon atoms, with a concentration of 20 ppm to 2000 ppm by mass.

20. The application according to any one of claims 16-19, characterized in that, The application employs a fixed-bed adsorption method, in which the purifying agent is filled into a purification tower, and the olefin disproportionation feedstock is introduced into the purification tower to contact with the purifying agent for purification, thereby obtaining purified olefin disproportionation feedstock.

21. The application according to claim 20, characterized in that, The purification conditions are as follows: Gas phase, volume hourly space velocity (VHSV) of 1000~20000 h⁻¹ -1 The bed temperature of the purification tower is 20~150℃, and the pressure of the purification tower is 0.1 MPa~6MPa.

22. The application according to claim 21, characterized in that, The purification conditions are as follows: the bed temperature of the purification tower is 40~120℃.

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