A process and system for the production of ethylene, propylene, co-product 1-butene and / or 2-butene

Abstract

The application discloses a method and system for producing ethylene and propylene while co-producing 1-butene and / or 2-butene, which comprises the following steps: (1) raw material methanol is reacted with a molecular sieve catalyst to obtain a mixture stream; (2) the mixture stream is separated to obtain an ethylene stream, a propylene stream and a C4 hydrocarbon stream; (3) the C4 hydrocarbon stream is subjected to heavy removal treatment to obtain a mixed carbon four hydrocarbon stream; (4) the mixed carbon four hydrocarbon stream is subjected to hydrogen isomerization treatment to obtain a 2-butene-rich material; the method further comprises the following steps: (5) removing isobutene in the 2-butene-rich material to obtain high-purity 2-butene; (6) 2-butene isomerization treatment to obtain a 1-butene-rich material, and optionally (7) selective hydrogenation treatment to obtain high-purity 1-butene. The method can produce ethylene and propylene while co-producing 2-butene and / or 1-butene.

Description

Technical Field

[0001] This invention relates to the production of ethylene, propylene and butene, and more particularly to a method and system for producing ethylene and propylene while simultaneously producing 1-butene and / or 2-butene. Background Technology

[0002] Currently, olefin production technology heavily relies on petroleum. However, with petroleum resources becoming increasingly scarce, the demand for olefins continues to grow rapidly. Therefore, the MTO (methanol-to-olefins) process, which uses coal or natural gas as feedstock to produce methanol and then low-carbon olefins, is gradually gaining attention from both academia and industry.

[0003] In recent years, with the surge in oil prices, the number of industrial plants using MTO technology to produce low-carbon olefins has increased year by year, and the output of its by-product, mixed C4, has also increased rapidly. However, in industry, most of the by-product C4 is directly used as fuel, wasting a large amount of olefin resources. Therefore, improving the comprehensive utilization rate of MTO by-product C4 resources has become a new economic growth point for enterprises.

[0004] CN103965003A relates to a method for producing butadiene, mainly addressing the technical problems of low carbon utilization, low utilization value of C4 hydrocarbons, and low economic efficiency in the methanol-to-olefins process in existing technologies. This invention employs the following steps: a) converting methanol-containing raw materials into a product stream containing ethylene, propylene, C4 olefins, and higher hydrocarbons under effective conditions; after separation, ethylene, propylene, mixed C4 and higher hydrocarbons, and other byproducts are obtained; b) after separating isobutane, isobutene, and n-butane components from the mixed C4 hydrocarbons, a butene-containing stream is obtained; the butene-containing stream undergoes an oxidative dehydrogenation reaction with oxygen-containing gas and water vapor in a reactor, in contact with a catalyst, to obtain a butadiene-rich stream. This technical solution effectively solves the problem and can be used for the industrial production of butadiene.

[0005] CN114133309A relates to a method for producing low-carbon olefins from methanol. This method employs a two-stage fluidized bed reactor, with an upper MTO reaction section and a lower C4 / C5 reaction section. The MTO reaction products are separated into dry gas, ethylene, propylene, C4, C5, and aromatic oil. Ethylene and propylene products exit the unit. The C4 / C5 reaction section mainly involves the cracking of C4 followed by etherification to produce ethylene and propylene. However, this existing technology is complex and requires etherification and cracking of C4, resulting in high energy consumption.

[0006] Currently, there are no methods for producing ethylene and propylene using the methanol-to-olefins (MTO) process, while simultaneously producing 1-butene and / or 2-butene. Summary of the Invention

[0007] To overcome the problems existing in the prior art, the present invention provides a method and system for producing ethylene and propylene while simultaneously producing 1-butene and / or 2-butene. The method includes first preparing ethylene and propylene using methanol to obtain mixed C4, and then processing the mixed C4 to obtain 2-butene and / or 1-butene. The method realizes the simultaneous production of ethylene and propylene while simultaneously producing 1-butene and / or 2-butene.

[0008] One objective of this invention is to provide a method for producing ethylene and propylene while simultaneously producing 1-butene and / or 2-butene, comprising:

[0009] (1) The raw material methanol reacts with a molecular sieve catalyst to obtain a mixture stream;

[0010] (2) The mixture stream is separated to obtain an ethylene stream, a propylene stream, and a C4+ hydrocarbon stream;

[0011] (3) The C4 and above hydrocarbon streams are subjected to deweighting treatment to obtain a mixed C4 hydrocarbon stream;

[0012] (4) The mixed C4 hydrocarbon stream is subjected to hydroisomerization to obtain 2-butene-rich material.

[0013] In a preferred embodiment, in step (1), the molecular sieve catalyst is selected from aluminum phosphate molecular sieve catalysts, preferably from at least one of SAPO-34 molecular sieve, SAPO-44 molecular sieve, SAPO-47 molecular sieve, SAPO-5 molecular sieve, and SAPO-56 molecular sieve.

[0014] In a preferred embodiment, the reaction conditions in step (1) include: a reaction temperature of 350–500°C, a reaction pressure of 0.1–1.0 MPa, and a methanol space velocity of 2–10 h⁻¹. -1 .

[0015] For example, the reaction conditions in step (1) include: a reaction temperature of 350℃, 380℃, 400℃, 420℃, 450℃, 480℃ or 500℃, a reaction pressure of 0.1MPa, 0.2MPa, 0.4MPa, 0.6MPa, 0.8MPa or 1.0MPa, and a methanol space velocity of 2h. -1 4h -1 6h -1 8h -1 or 10h -1 .

[0016] In a further preferred embodiment, the reaction conditions in step (1) include: a reaction temperature of 400–500°C, a reaction pressure of 0.1–0.5 MPa, and a methanol space velocity of 2–5 h⁻¹. -1 .

[0017] In a preferred embodiment, the separation in step (2) is performed by distillation.

[0018] In step (2), the separation or distillation can be carried out using publicly available technologies. The conditions for separation or distillation are not particularly limited, as long as the mixture stream can be separated to obtain ethylene stream, propylene stream and C4 or higher hydrocarbon stream. For example, the distillation or separation methods disclosed in CN103880577A and / or CN101921161A can be used.

[0019] For example, when using the system described in CN103880577A, the C4+ hydrocarbon stream described in step (1) of this invention is obtained from the bottom of the propane removal tower described in CN103880577A, the ethylene stream is obtained from the top of the ethylene distillation tower described in CN103880577A, and the propylene stream is obtained from the top of the propylene distillation tower described in CN103880577A. Optionally, a portion of the mixed C4 hydrocarbons obtained after the heavy removal treatment described in this invention can be collected and connected to the ethylene recovery tower described in CN103880577A.

[0020] In a further preferred embodiment, the separation in step (2) includes: (2.1) distilling the mixture stream to obtain a hydrocarbon stream with less than C3 and a hydrocarbon stream with more than C4, and (2.2) distilling the hydrocarbon stream with less than C3 to obtain an ethylene stream and a propylene stream, respectively.

[0021] The distillation processes in steps (2.1) and (2.2) are very mature in the prior art and are easy to implement for those skilled in the art. For details, please refer to CN103880577A.

[0022] Steps (1) to (2) of the present invention can also be carried out using any MTO process disclosed in the prior art, as long as methanol can be used to prepare and separate ethylene stream, propylene stream and C4 or higher hydrocarbon stream.

[0023] In a preferred embodiment, the C4 and above hydrocarbon stream contains a mixture of C4 and above olefins (including butadiene, 1-butene, 2-butene, and isobutene), aldehydes and ketones, optionally methanol, and optionally C5 and above hydrocarbons.

[0024] In a further preferred embodiment, the C4 and above hydrocarbon stream contains 60-98 wt% mixed C4 olefins, 700 ppm or more aldehydes and ketones, 0-1000 ppm methanol, and 0.5-40 wt% C5 and above hydrocarbons.

[0025] For example, the C4 and above hydrocarbon stream contains: 60wt%, 65wt%, 70wt%, 75wt%, 80wt%, 85wt%, 90wt%, 95wt%, or 98wt% mixed C4 olefins, 700ppm or more aldehydes and ketones, 0ppm, 10ppm, 50ppm, 100ppm, 200ppm, 400ppm, 600ppm, 800ppm, or 1000ppm methanol, and 0.5wt%, 1wt%, 5wt%, 10wt%, 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, or 40wt% C5 and above hydrocarbons.

[0026] In a preferred embodiment, in step (3), the weight removal process is carried out by distillation.

[0027] Among them, after extensive experimental research, the inventors discovered for the first time that aldehydes and ketones in the material have a great inhibitory effect on the hydroisomerization described in step (4). Therefore, the present invention uses a deweighting method to remove aldehydes and ketones from hydrocarbon streams containing C4 and above.

[0028] In a further preferred embodiment, in step (3), the distillation conditions include: a top temperature of 40–60°C, a bottom temperature of 70–100°C, and a pressure of 0.3–0.7 MPa.

[0029] For example, the distillation conditions include: a column top temperature of 40°C, 45°C, 50°C, 55°C, or 60°C; a column bottom temperature of 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, or 100°C; and a pressure of 0.3 MPa, 0.35 MPa, 0.4 MPa, 0.45 MPa, 0.5 MPa, 0.6 MPa, or 0.7 MPa.

[0030] In a further preferred embodiment, in step (3), the distillation conditions include: a top temperature of 45-55°C, a bottom temperature of 75-95°C, and a pressure of 0.35-0.45 MPa.

[0031] In this invention, distillation is used to remove heavy components. This not only removes aldehydes and ketones from C4 and above hydrocarbon streams, but also removes selectively chosen C5 and above hydrocarbons and other heavy components from the C4 and above hydrocarbon streams.

[0032] In a preferred embodiment, after the distillation process, the mixed C4 hydrocarbon stream is obtained at the top of the column, and the heavy components are discharged from the bottom of the column.

[0033] In a preferred embodiment, the content of aldehydes and ketones in the mixed C4 hydrocarbon stream obtained in step (3) is 50 to 550 ppm, for example, 50 ppm, 100 ppm, 150 ppm, 200 ppm, 250 ppm, 300 ppm, 350 ppm, 400 ppm, 450 ppm, 500 ppm or 550 ppm.

[0034] Through extensive experimental research, the inventors discovered that: (1) when the content of aldehydes and ketones in the mixed C4 hydrocarbon stream is higher than 550 ppm, it inhibits the isomerization of 1-butene and the selective hydrogenation of 1,3-butadiene; (2) when the content of aldehydes and ketones in the mixed C4 hydrocarbon stream is lower than 50 ppm, it leads to the over-hydrogenation of butene to generate butane, increasing butene loss and negatively impacting process economy. Therefore, the technical solution of this invention is to leave a small amount of aldehydes and ketones to prevent the formation of butane, the over-hydrogenation product.

[0035] In a preferred embodiment, the aldehyde and / or ketone compounds preferably include at least one of aldehyde and ketone compounds such as acetaldehyde, propionaldehyde, butyraldehyde, acetone, and butanone.

[0036] In a preferred embodiment, the hydroisomerization treatment in step (4) is carried out in the presence of a hydroisomerization catalyst.

[0037] In a further preferred embodiment, the hydroisomerization catalyst comprises a support and an active component; preferably, the support is selected from at least one of metal oxides and activated carbon, more preferably from at least one of alumina, silica, activated carbon, titanium dioxide, zirconium oxide, and iron oxide; and / or, the active component is selected from at least one of copper, nickel, platinum, and palladium, more preferably from nickel and / or palladium.

[0038] In a further preferred embodiment, the content of the active component is 0.01 to 30 wt%, preferably 0.1 to 20 wt%, based on a total content of 100 wt% of the carrier and the active component.

[0039] For example, based on a total content of 100 wt% for the carrier and active component, the content of the active component is 0.01 wt%, 0.05 wt%, 0.1 wt%, 0.5 wt%, 1 wt%, 5 wt%, 15 wt%, 20 wt%, 25 wt%, or 30 wt%.

[0040] In this invention, the hydroisomerization can also be carried out using any other catalyst disclosed in the prior art that can perform mixed C4 hydroisomerization, as long as it can achieve the hydroisomerization described in step (4) of this invention.

[0041] In a preferred embodiment, the hydroisomerization process in step (4) is carried out in the presence of hydrogen, wherein 1,3-butadiene is selectively hydrogenated to 1-butene, and 1-butene isomerized to 2-butene.

[0042] The mixed C4 hydrocarbon stream contains butadiene, 1-butene, 2-butene, and isobutene. However, isobutene and 1-butene differ in boiling point by only 0.6°C and in relative volatility by only 0.03, making separation difficult using conventional distillation methods. In this invention, through the aforementioned hydroisomerization treatment, the 1-butene and 1,3-butadiene in the mixed C4 stream are selectively hydrogenated to generate 1-butene, which is isomerized to 2-butene. 2-Butene can then be effectively separated from isobutene, solving the problem of the inability to separate isobutene and 1-butene due to their similar boiling points.

[0043] In a further preferred embodiment, the conditions for the hydroisomerization treatment in step (4) include: a temperature of 30 to 100°C and / or a pressure of 0.1 to 5 MPa.

[0044] For example, the hydroisomerization process described in step (4) is carried out in the presence of hydrogen, and the processing conditions include: a temperature of 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C or 100°C, and / or a pressure of 0.1 MPa, 0.5 MPa, 1 MPa, 2 MPa, 3 MPa, 4 MPa or 5 MPa.

[0045] In the method described in this invention, more than 75% of 1-butene in the mixed C4 hydrocarbon stream is isomerized to 2-butene, while more than 99% of 1,3-butadiene is selectively hydrogenated to 1-butene, and the increase in the mass percentage of n-butane in the 2-butene-rich material obtained in step (4) is less than 1 unit (e.g., ppm).

[0046] In a preferred embodiment, the method further includes: (5) removing isobutene from the 2-butene-rich material to obtain high-purity 2-butene.

[0047] In a further preferred embodiment, the removal described in step (5) is performed by distillation.

[0048] Among them, existing technologies can be used to remove isobutene from the 2-butene-rich material described in step (4).

[0049] In a further preferred embodiment, in step (5), the distillation conditions include: a top temperature of 40–60°C (e.g., 40°C, 45°C, 50°C, 55°C, or 60°C), a bottom temperature of 50–90°C (e.g., 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, or 90°C), and a pressure of 0.3–0.7 MPa (e.g., 0.3 MPa, 0.4 MPa, 0.5 MPa, 0.6 MPa, or 0.7 MPa).

[0050] In a preferred embodiment, the method optionally further includes: (6) isomerizing the 2-butene material to obtain 1-butene-containing material I, and optionally (7) selectively hydrogenating the 1-butene-containing material I to obtain 1-butene-containing material II.

[0051] In step (6), 2-butene isomerizes to 1-butene. During this isomerization process, a small amount of 1,3-butadiene may be generated. Therefore, step (7) is optionally performed after step (6), in which 1,3-butadiene is selectively hydrogenated to 1-butene.

[0052] The isomerization process described in step (6) can be carried out using any conditions or processes disclosed in the prior art that can isomerize 2-butene to 1-butene, and the selective hydrogenation process described in step (7) can be carried out using any conditions or processes disclosed in the prior art that can selectively hydrogenate 1,3-butadiene to 1-butene.

[0053] Thus, after steps (6) and (7), the method can yield ethylene, propylene, and 1-butene.

[0054] In a further preferred embodiment, the conditions for the isomerization treatment in step (6) include: a mass hourly space velocity (HHSV) of 5 to 30 h⁻¹ for the material (high-purity 2-butene). -1 For example, 5h -1 10h -1 15h -1 20h -1 25h -1 or 30h -1 The pressure is 0.1 to 1.2 MPa, for example, 0.1 MPa, 0.2 MPa, 0.4 MPa, 0.6 MPa, 0.8 MPa, 1 MPa or 1.2 MPa; the temperature is 220℃ to 450℃, for example, 220℃, 250℃, 280℃, 300℃, 320℃, 350℃, 380℃, 400℃, 420℃ or 450℃.

[0055] In step (6), the isomerization process is carried out in the presence of a catalyst, which can be selected from any catalyst disclosed in the prior art that can isomerize 2-butene to 1-butene, such as the catalysts prepared in documents CN102649673A and CN102649671A.

[0056] In a further preferred embodiment, the conditions for selecting hydrogenation in step (7) include: a mass hourly space velocity (HHSV) of 1.5 to 15 h⁻¹ for the feedstock (1-butene-rich feedstock). -1 For example, 1.5h -1 2h -1 4h -1 6h -1 8h -1 10h -1 12h -1 14h -1 or 15 hours -1 The pressure is 0.6 to 3.0 MPa, for example, 0.6 MPa, 1 MPa, 1.5 MPa, 2 MPa, 2.5 MPa or 3.0 MPa; the temperature is 30 to 60°C, for example, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C or 60°C; the molar ratio of hydrogen to 1,3-butadiene is 1 to 30.

[0057] In step (7), the selective hydrogenation is carried out in the presence of a catalyst, which is selected from any catalyst disclosed in the prior art that can selectively hydrogenate 1,3-butadiene to 1-butene, such as the catalysts described in references CN110639517A and / or CN109092303A.

[0058] In this invention, steps (6) and (7) can be performed or not. When steps (6) and (7) are not performed, the method of this invention yields ethylene, propylene, and 2-butene. When steps (6) and (7) are performed, the method of this invention yields ethylene, propylene, and 1-butene.

[0059] In this invention, "rich in...materials" means "materials including..." or "logistics mainly composed of...".

[0060] The higher isomerization efficiency described in this invention includes: higher 1-butene conversion, higher 2-butene selectivity, and can prevent the formation of butane, a product of over-hydrogenation, to the greatest extent possible.

[0061] A second objective of this invention is to provide a system for producing ethylene and propylene while simultaneously producing 1-butene and / or 2-butene, preferably for carrying out the method described in one objective of this invention, wherein the system includes a methanol-to-olefins unit, a mixed stream separation unit, a de-heavy stream unit, and a hydroisomerization unit.

[0062] In a preferred embodiment, the methanol-to-olefins unit is a fluidized bed reactor.

[0063] The methanol-to-olefins unit can be any methanol-to-olefins system disclosed in the prior art, such as an MTO system.

[0064] In a further preferred embodiment, the molecular sieve catalyst is packed inside the fluidized bed reactor.

[0065] In a preferred embodiment, the mixture stream separation unit includes one or more distillation columns.

[0066] In this invention, the mixture stream separation unit employs any system disclosed in the prior art that can successfully separate ethylene stream, propylene stream and C4+ hydrocarbon stream, such as the separation system disclosed in CN103880577A and / or CN101921161A.

[0067] In a further preferred embodiment, the mixture stream separation unit includes: (i) a propane stripper for separating C3 and below hydrocarbon streams and C4 and above hydrocarbon streams; and (ii) multiple distillation columns for separating C3 and below hydrocarbons to obtain ethylene and propylene, respectively. For example, the multiple distillation columns include a methanogen stripper, an ethane stripper, an ethylene distillation column, and a propylene distillation column, etc.

[0068] The setup of (i) the propane removal column and (ii) the plurality of distillation columns can be found in CN103880577A.

[0069] In a preferred embodiment, the deweighting unit includes a distillation column A, with a raw material inlet in the middle of the distillation column A, a mixed C4 hydrocarbon stream outlet at the top of the distillation column A, and a heavy component outlet at the bottom of the distillation column A.

[0070] The recombinant components include aldehydes and ketones and optionally hydrocarbons with more than 5 carbon atoms.

[0071] In a further preferred embodiment, the conditions of the distillation column A include: a top temperature of 40–60°C, a bottom temperature of 70–100°C, and a pressure of 0.3–0.7 MPa.

[0072] In a further preferred embodiment, the conditions of the distillation column A include: a top temperature of 45–55°C, a bottom temperature of 75–95°C, and a pressure of 0.35–0.45 MPa.

[0073] In a preferred embodiment, the hydroisomerization unit is a fixed-bed reactor.

[0074] In a further preferred embodiment, the hydroisomerization catalyst is packed inside the fixed-bed reactor.

[0075] In a further preferred embodiment, the conditions of the fixed-bed reactor include: a temperature of 30–100°C and / or a pressure of 0.1–5 MPa.

[0076] In a preferred embodiment, the system further includes an isobutylene removal unit; preferably, along the material flow direction, the isobutylene removal unit is disposed after the hydroisomerization unit, and is used to remove isobutylene from the 2-butene-rich material to obtain high-purity 2-butene.

[0077] In a further preferred embodiment, the isobutylene removal unit includes a distillation column B.

[0078] In a further preferred embodiment, a 2-butene-rich material inlet is provided in the middle of the distillation column B, an isobutene material outlet is provided at the top of the distillation column B, and a high-purity 2-butene outlet is provided at the bottom of the distillation column B.

[0079] In a preferred embodiment, the system may further optionally include a 2-butene isomerization unit and an optional selective hydrogenation unit, preferably arranged sequentially after the isobutene removal unit along the material flow direction.

[0080] The 2-butene isomerization unit is used to isomerize 2-butene to 1-butene, and the selective hydrogenation unit is used to selectively hydrogenate 1,3-butadiene to 1-butene.

[0081] In a further preferred embodiment, the 2-butene isomerization unit and the selective hydrogenation unit are each independently a fixed-bed reactor.

[0082] The catalyst is packed in the fixed-bed reactor of the 2-butene isomerization unit. This catalyst can be selected from any catalyst disclosed in the prior art that can isomerize 2-butene to 1-butene, such as the catalysts prepared in references CN102649673A and CN102649671A. The catalyst is also packed in the fixed-bed reactor of the selective hydrogenation unit. This catalyst is selected from any catalyst disclosed in the prior art that can selectively hydrogenate 1,3-butadiene to 1-butene, such as the catalysts described in references CN110639517A and / or CN109092303A.

[0083] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values; these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. In the following, various technical solutions can, in principle, be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0084] Compared with the prior art, the present invention has the following beneficial effects:

[0085] (1) The method of the present invention can produce 2-butene and / or 1-butene simultaneously with the production of ethylene and propylene;

[0086] (2) The method described in this invention can make full use of the mixed C4 produced by methanol-to-olefins to produce high-purity 2-butene and / or 1-butene, improve the chemical utilization rate of mixed C4 in China, and has high industrial application value.

[0087] (3) Step (4) of the method described in this invention has high isomerization efficiency;

[0088] (4) The method described in this invention can separate isobutylene in mixed C4. Attached Figure Description

[0089] Figure 1 A schematic diagram of the structure of the system described in this invention is shown. Figure 1 .

[0090] Figure 2 A schematic diagram of the structure of the system described in this invention is shown. Figure 2 .

[0091] A: Methanol to Olefins Unit, B: Mixture Stream Separation Unit, C: Heavy Stream Removal Unit, D: Hydroisomerization Unit, E: Deisobutene Unit, F: 2-Butene Isomerization Unit, G: Selective Hydrogenation Unit, 1: Feed Methanol, 2: Mixture Stream, 3.1: Ethylene Stream, 3.2: Propylene Stream, 4: C4+ Hydrocarbon Stream, 5: Mixed C4 Hydrocarbon Stream, 6: Heavy Components, 7: Hydroisomerization Product, 8: 2-Butene, 9: Isobutene, 10: Isomerization Product, 11: 1-Butene.

[0092] Figure 3 The diagram shows the structural schematics of the de-heavy unit and the hydroisomerization unit in the system described in this invention.

[0093] C: De-heavy unit, D: Hydrogenation isomerization unit, H: Pump, I: Reflux tank, J: Degassing tank, 12: Hydrogen, 13: Non-condensable gas removal, 14: Product refining. Detailed Implementation

[0094] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0095] It should also be noted that the various specific technical features described in the following embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the various possible combinations will not be described separately in this invention.

[0096] Furthermore, various embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention. The resulting technical solutions are part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0097] Unless otherwise specified, the raw materials used in the examples and comparative examples are all disclosed in the prior art, such as those that can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0098] In the embodiments and comparative examples of the present invention:

[0099] 1-Butene conversion rate = (1-Butene content in raw material - 1-Butene content in product) / 1-Butene content in raw material;

[0100] 2-Butene selectivity = (2-Butene content in product - 2-Butene content in raw material) / (1-Butene content in raw material - 1-Butene content in product + 1,3-Butadiene content in raw material - 1,3-Butadiene content in product);

[0101] 1,3-Butadiene conversion rate = (1,3-Butadiene content in feedstock - 1,3-Butadiene content in product) / 1,3-Butadiene content in feedstock

[0102] Butane increment = Butane content per unit product - Butane content per unit raw material.

[0103] [Example 1] Preparation of Catalyst I

[0104] 300g of alumina support was mixed with 1000g of chloropalladic acid aqueous solution containing 1.2g of palladium, dried at 110℃ and calcined at 550℃ for 4h to obtain catalyst I with a Pd loading of 0.4%.

[0105] [Example 2] Preparation of Catalyst II

[0106] 300g of alumina support was mixed with 400g of nickel ammonia solution containing 50g of nickel, dried at 110℃ and calcined at 450℃ for 4h to obtain catalyst II with a Ni loading of 15%.

[0107]

Example 3

[0108] use Figure 1 and Figure 3 The system shown is being implemented.

[0109] Methanol was contacted with a SAPO-34 molecular sieve catalyst at a reaction temperature of 460°C, a reaction pressure of 0.1 MPa, and a methanol space velocity of 3 h⁻¹. 1 At that time, a mixture stream was obtained through the reaction.

[0110] The mixture stream was processed using method CN103880577A to obtain a stream of hydrocarbons with C4 or higher content, the composition of which is shown in Table 1 below:

[0111] Table 1:

[0112] butadiene 1.56wt% 1-Butene 19.50wt% 2-Butene 44.53wt% Isobutylene 3.27wt% Aldehydes and ketones 1300ppm Hydrocarbons with C5 or higher margin methanol 10ppm

[0113] The hydrocarbon streams with C4 and above shown in Table 1 were subjected to distillation at a top temperature of 48°C, a bottom temperature of 88°C, and a top pressure of 0.4 MPa. The resulting stream contained a mixed C4 hydrocarbon stream with an aldehyde and ketone content of 270 ppm, as shown in Table 2 below.

[0114] Table 2:

[0115]

[0116]

[0117] Hydroisomerization was performed on the mixed C4 hydrocarbon stream from the top of the column: in a fixed bed, catalyst I was used, the reaction temperature was 55℃, and the pressure was 1.5MPa, yielding a 2-butene-rich feed. The results are shown in Table I.

[0118] Isobutylene removal: The 2-butene-rich material is subjected to distillation at a top temperature of 50°C, a bottom temperature of 64.9°C, and a top pressure of 0.5 MPa. The top of the distillation yields a light component rich in isobutylene, while the bottom of the distillation yields high-purity 2-butene with a purity of 99.2 wt%.

[0119]

Example 4

[0120] use Figure 1 and Figure 3 The system shown is being implemented.

[0121] Methanol was contacted with a SAPO-34 molecular sieve catalyst at a reaction temperature of 480℃, a reaction pressure of 0.3 MPa, and a methanol space velocity of 6 h⁻¹. -1 At that time, a mixture stream was obtained through the reaction.

[0122] The mixture stream was processed using method CN103880577A to obtain a stream of hydrocarbons with C4 or higher content, the composition of which is shown in Table 3 below:

[0123] Table 3:

[0124]

[0125]

[0126] The hydrocarbon streams with C4 and above shown in Table 1 were subjected to distillation at a top temperature of 50°C, a bottom temperature of 93°C, and a top pressure of 0.45 MPa. The resulting stream contained 440 ppm of aldehydes and ketones, and its composition is shown in Table 4 below.

[0127] Table 4:

[0128] butadiene 1.77wt% 1-Butene 25.55wt% 2-Butene 67.07wt% Isobutylene 5.65wt% Aldehydes and ketones 440ppm Hydrocarbons with C5 or higher margin methanol 10ppm

[0129] Hydroisomerization of the mixed C4 hydrocarbon stream at the top of the column was performed: In a fixed bed, catalyst II was selected, and catalyst B was first reduced at 440℃ for 6 hours, followed by C4 hydroisomerization at 55℃ and 1.5 MPa to obtain a 2-butene-rich feed. The results are shown in Table I.

[0130] Isobutylene removal: The hydroisomerized product is subjected to distillation at a top temperature of 51°C, a bottom temperature of 64.9°C, and a top pressure of 0.53 MPa. The top of the column yields a light component rich in isobutylene, while the bottom yields high-purity 2-butene with a purity of 99.3 wt%.

[0131]

Example 5

[0132] use Figure 1 and Figure 3 The system shown is being implemented.

[0133] The hydrocarbon streams with C4 and above shown in Table 1 were subjected to distillation at a top temperature of 48°C, a bottom temperature of 85°C, and a top pressure of 0.4 MPa. The resulting stream was a mixed C4 hydrocarbon stream with an aldehyde and ketone content of 160 ppm.

[0134] Hydroisomerization of the mixed C4 hydrocarbon stream at the top of the column was performed in a fixed bed reactor using catalyst I at a reaction temperature of 55°C and a pressure of 1.5 MPa. The results are shown in Table I.

[0135] Isobutylene removal: The hydroisomerized product is subjected to distillation at a top temperature of 50°C, a bottom temperature of 64.9°C, and a top pressure of 0.55 MPa. The top of the column yields a light component rich in isobutylene, while the bottom yields high-purity 2-butene with a purity of 99.2 wt%.

[0136]

Example 6

[0137] use Figure 1 and Figure 3 The system shown is being implemented.

[0138] The hydrocarbon streams with C4 and above shown in Table 1 were subjected to distillation at a top temperature of 51°C, a bottom temperature of 94°C, and a top pressure of 0.41 MPa. The resulting stream contained 430 ppm of aldehydes and ketones, and its composition is shown in Table 2 below.

[0139] Hydroisomerization was performed on the mixed C4 hydrocarbon stream from the top of the column: in a fixed bed, catalyst I was used, the reaction temperature was 55℃, and the pressure was 1.5MPa, yielding a 2-butene-rich feed. The results are shown in Table I.

[0140] Isobutylene removal: The hydroisomerized product is subjected to distillation at a top temperature of 49°C, a bottom temperature of 64.9°C, and a top pressure of 0.48 MPa. The top of the column yields a light component rich in isobutylene, while the bottom yields high-purity 2-butene with a purity of 99.3 wt%.

[0141] Comparative Example 1

[0142] The process of Example 3 was repeated, except that no deweighting treatment was performed. The results are shown in Table I.

[0143] Comparative Example 2

[0144] The process of Example 4 was repeated, except that no deweighting treatment was performed. The results are shown in Table I.

[0145] Comparative Example 3

[0146] The process of Example 1 was repeated, except that the deweighting conditions were different: the top temperature of the column was 38°C, the bottom temperature of the column was 64°C, the top pressure of the column was 0.42 MPa, and the mixed C4 hydrocarbon stream contained 5 ppm of aldehydes and ketones.

[0147] Table I:

[0148]

[0149]

Example 7

[0150] use Figure 2 and Figure 3 The system is in operation.

[0151] (1) Repeat the process of Example 3 to obtain high-purity 2-butene;

[0152] (2) Isomerization of high-purity 2-butene to 1-butene:

[0153] The 2-butene isomerization catalyst was prepared by mixing a slurry containing silicon, aluminum, a template agent, and water at a silicon-to-aluminum molar ratio (SiO2 / Al2O3) of 200. 150 g of ZSM-5 molecular sieve was synthesized at 130 °C for 70 hours. Then, 18 g of 40% (by weight) silica sol was added, mixed, extruded, and dried at 120 °C to obtain the sample. 90 g of this sample was weighed and placed in a sealed reactor, treated in an aqueous solution containing n-butylamine template agent at 110 °C for 130 hours. After washing, drying, and calcination, the sample was placed in 1000 mL of 5% (by weight) NH4NO3 solution and exchanged at 80–90 °C for 3 hours, repeated three times. After exchange, the sample was dried at 120 °C and calcined at 620 °C to obtain a 2-butene isomerization catalyst with a crystallinity of 96.8%.

[0154] Reaction conditions: In the presence of the catalyst prepared above, mass hourly space velocity (WHSV) was 9 h⁻¹. -1 The pressure was 0.45 MPa and the reaction temperature was 325 °C, and 1-butene-containing material I was obtained, which contained 40.9 wt% 1-butene and 0.01 wt% 1,3-butadiene.

[0155] (2) Selective hydrogenation of 1,3-butadiene to 1-butene:

[0156] A selective hydrogenation catalyst for 1,3-butadiene was prepared by mixing 99.2 g of alumina support, 37.5 g of an aqueous solution containing 0.15 g of cerium nitrate, and 37.5 g of an aqueous solution containing 0.15 g of lanthanum nitrate. The mixture was dried at 110 °C and calcined at 450 °C for 4 h to obtain a sample. This sample was then mixed with 100 g of an aqueous solution containing 0.5 g of palladium chloropalladium acid, dried at 110 °C, and calcined at 450 °C for 4 h to obtain a catalyst with a palladium loading of 0.5%.

[0157] Reaction conditions: In the presence of the catalyst obtained above, mass hourly space velocity (WHSV) was 10 h⁻¹. -1 The pressure was 1.7 MPa, the reaction temperature was 36 °C, and the hydrogen / 1,3-butadiene molar ratio was 11, yielding 1-butene-containing material II with a purity of 40.5 wt%.

[0158]

Example 8

[0159] use Figure 2 and Figure 3 The system is in operation.

[0160] (1) Repeat the process of Example 4 to obtain high-purity 2-butene;

[0161] The catalyst was prepared by mixing a slurry containing silicon, aluminum, a template agent, and water at a silicon-to-aluminum molar ratio (SiO2 / Al2O3) of 200. The slurry was then subjected to a 70-hour drying process at 130°C to synthesize 150 g of ZSM-5 molecular sieve. 18 g of 40% (by weight) silica sol was added and mixed. The mixture was then extruded, dried at 120°C, and the sample was obtained. 90 g of this sample was placed in a sealed reactor and treated in an aqueous solution containing n-butylamine template agent at 110°C for 130 h. After washing, drying, and calcination, the sample was placed in 1000 mL of 5% (by weight) NH4NO3 solution and subjected to an exchange process at 80–90°C for 3 h. This process was repeated three times. After the exchange process, the sample was dried at 120°C and calcined at 620°C to obtain a catalyst with a crystallinity of 96.8%.

[0162] Reaction conditions: In the presence of the catalyst prepared above, mass hourly space velocity (WHSV) was 12 h⁻¹. -1 The pressure was 0.4 MPa and the reaction temperature was 330 °C, and 1-butene-containing material I was obtained, which contained 42.5 wt% 1-butene and 0.01 wt% 1,3-butadiene.

[0163] (2) Selective hydrogenation of 1,3-butadiene to 1-butene:

[0164] Preparation of a selective hydrogenation catalyst for 1,3-butadiene: 99.5 g of alumina support and 100 g of chloropalladic acid aqueous solution containing 0.5 g of palladium were mixed, dried at 110 °C, and calcined at 450 °C for 4 h to obtain a catalyst with a palladium loading of 0.5%.

[0165] Reaction conditions: In the presence of the catalyst obtained above, mass hourly space velocity (WHSV) 4 h⁻¹ -1 The pressure was 1.4 MPa, the reaction temperature was 38 °C, and the hydrogen / 1,3-butadiene molar ratio was 1.1, yielding 1-butene-containing material II with a purity of 44 wt%.

[0166] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A method for producing ethylene and propylene while simultaneously producing 1-butene and / or 2-butene, comprising: (1) The raw material methanol reacts with the molecular sieve catalyst to obtain a mixture stream; (2) The mixture stream is separated to obtain an ethylene stream, a propylene stream and a C4+ hydrocarbon stream; the C4+ hydrocarbon stream contains 60~98wt% mixed C4 olefins, 700ppm+ aldehydes and ketones, 0~1000ppm methanol, and 0.5~40wt% C5+ hydrocarbons; (3) The C4 and above hydrocarbon streams are subjected to deweight treatment to obtain mixed C4 hydrocarbon streams; the content of aldehydes and ketones in the mixed C4 hydrocarbon streams obtained in step (3) is 50~550 ppm; (4) The mixed C4 hydrocarbon stream is subjected to hydroisomerization treatment to obtain 2-butene-rich material; the hydroisomerization catalyst includes a support and an active component, wherein the support is selected from at least one of metal oxides and activated carbon, and the active component is selected from palladium.

2. The method according to claim 1, characterized in that, In step (1), the molecular sieve catalyst is selected from aluminum phosphate molecular sieve catalysts.

3. The method according to claim 1, characterized in that, The molecular sieve catalyst is selected from at least one of SAPO-34 molecular sieve, SAPO-44 molecular sieve, SAPO-47 molecular sieve, SAPO-5 molecular sieve, and SAPO-56 molecular sieve.

4. The method according to claim 1, characterized in that, The reaction conditions in step (1) include: a reaction temperature of 350~500℃, a reaction pressure of 0.1~1.0MPa, and a methanol space velocity of 2~10h. -1 .

5. The method according to claim 1, characterized in that, The separation described in step (2) is carried out by distillation.

6. The method according to claim 5, characterized in that, The separation in step (2) includes: (2.1) distilling the mixture stream to obtain hydrocarbon streams with less than C3 and hydrocarbon streams with more than C4, and (2.2) distilling the hydrocarbon streams with less than C3 to obtain ethylene streams and propylene streams respectively.

7. The method according to claim 1, characterized in that, In step (3), the deweighting process is carried out by distillation; the distillation conditions include: the top temperature of the column is 40~60℃, the bottom temperature of the column is 70~100℃, and the pressure is 0.3~0.7MPa.

8. The method according to claim 1, characterized in that, The hydroisomerization treatment in step (4) is carried out in the presence of a hydroisomerization catalyst; and / or, The conditions for the hydroisomerization treatment in step (4) include: a temperature of 30~100℃ and / or a pressure of 0.1~5MPa.

9. The method according to claim 1, characterized in that, Based on a total content of 100wt% for the carrier and active components, the content of the active components is 0.01~30wt%.

10. The method according to claim 1, characterized in that, The active component content is 0.1~20wt% based on a total content of 100wt% for the carrier and active component.

11. The method according to any one of claims 1 to 10, characterized in that, The method further includes: (5) removing isobutene from the 2-butene-rich material to obtain 2-butene.

12. The method according to claim 11, characterized in that, The removal in step (5) is carried out by distillation; the distillation conditions include: the top temperature of the column is 40~60℃, the bottom temperature of the column is 50~90℃, and the pressure is 0.3~0.7MPa.

13. The method according to claim 11, characterized in that, The method optionally further includes: (6) isomerizing the 2-butene material to obtain 1-butene-containing material I, and optionally (7) selectively hydrogenating the 1-butene-containing material I to obtain 1-butene-containing material II.

14. The method according to claim 13, characterized in that, The conditions for the isomerization process in step (6) include: a material mass hourly space velocity of 5 to 30 h⁻¹. -1 The pressure is 0.1~1.2MPa, and the temperature is 220℃~450℃; and / or, The conditions for selecting hydrogenation in step (7) include: a mass hourly space velocity (HHSV) of 1.5 to 15 h⁻¹. -1 The pressure is 0.6~3.0MPa, the temperature is 30~60℃, and the molar ratio of hydrogen to 1,3-butadiene is 1~30.

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