Separation adsorbent and use thereof

Abstract

The present invention relates to an ethylene-ethane separation adsorbent and a method for preparing the same, the adsorbent including a modified A-type molecular sieve and a carrier, wherein the modified A-type molecular sieve includes an A-type molecular sieve and a metal salt active component including a component M1 which is a metal salt of at least one of Mg 2+ , Ca 2+ , and Sr 2+ , and a component M2 which is a metal salt of at least one of Fe 2+ , Cr 3+ , Co 2+ , and Ni 2+ . The adsorbent has improved ethylene adsorption capacity and adsorption selectivity.

Description

Technical Field

[0001] This invention relates to the field of adsorption separation, and more particularly to a separation adsorbent and its application in concentrating ethylene in a mixture of ethylene and ethane. Background Technology

[0002] Ethylene is a crucial basic chemical raw material and a vital bridge between oil and chemical industries, with its production, apparent consumption, and demand increasing year by year. In many ethylene production processes, after gas separation, ethylene and ethane coexist. This is because the physicochemical properties of ethylene and ethane are quite similar, making separation difficult. Currently, the commonly used method in industry is cryogenic distillation. This method requires high pressure (0.7-2.8 MPa), extremely low temperature (-160℃), and distillation columns with multiple trays (>100) and high reflux ratios (2.5-4), resulting in high energy consumption, large investment, and complex operation. Therefore, there is an urgent need to develop efficient, energy-saving, and environmentally friendly methods for concentrating ethylene.

[0003] Currently, molecular sieves or porous adsorbents are used to separate ethylene and ethane at room temperature and pressure, but these methods suffer from drawbacks such as low adsorption capacity, low selectivity, and poor stability. For example, NaY molecular sieve has an adsorption capacity of 2.1 mmol / g for ethylene at room temperature and pressure, but its ethylene / ethane separation selectivity is only 1.4 (AICHE Journal, 1995, 41(3): 509-517). The all-silica molecular sieve ITQ-55 achieves ethylene / ethane separation through the kinetic difference in diffusion between ethylene and ethane, but its adsorption capacity for ethylene at room temperature and pressure is only 1.3 mmol / g (Science, 2017, 358: 1068-1071). In addition to using the aforementioned unmodified molecular sieve materials, there are also adsorbents based on transition metal ions, such as AgA molecular sieves (Journal of the American Chemical Society, 2012, 134(36): 14635-14637), organic porous materials PAF-1-SO3Ag (Journal of the American Chemical Society, 2014, 136(24): 8654-8660), and CuCl supported alumina (CN1048010C), which selectively adsorb ethylene through metal π-complexation. However, these adsorbents are easily contaminated by water, oxygen, reducing gases, and sulfur-containing compounds in the raw gas, have poor stability, are prone to deactivation, and have a short service life, making them unsuitable for industrial applications. Summary of the Invention

[0004] The purpose of this invention is to address the problems existing in the prior art by providing a separation adsorbent that differs from the prior art and to provide its application in the separation of ethylene and ethane.

[0005] To achieve the above objectives, a first aspect of the present invention provides a separation adsorbent, characterized in that it comprises a modified type A molecular sieve and a support; the modified type A molecular sieve comprises a type A molecular sieve and a metal salt active component for modification, the metal salt active component for modification comprising component M1 and component M2, wherein component M1 is selected from Mg 2+ Ca 2+ and Sr 2+ At least one of the metal salts, wherein component M2 is selected from Fe 2+ Fe 3+ Co 2+ and Ni 2+ The modified type A molecular sieve comprises 90-97 wt% and the support comprises 3-10 wt% based on the separation adsorbent; or the modified type A molecular sieve comprises 64.0-92.0 wt%, the active component of the modified metal salt comprises 8.0-36.0 wt%, component M1 comprises 1.5-30.0 wt%, and component M2 comprises 1.5-8.0 wt%.

[0006] In some embodiments, based on modified type A molecular sieves, component M1 is 5.0-26.0 wt% and component M2 is 1.6-7.5 wt%.

[0007] In some embodiments, the average grain size of the modified type A molecular sieve is not greater than 1 μm, preferably not greater than 0.9 μm, and more preferably 0.70-0.85 μm.

[0008] In some embodiments, the carrier is selected from at least one of kaolin, bentonite, montmorillonite, diatomite, rettoite, and halloysite.

[0009] In some embodiments, the separating adsorbent is a molded microsphere with a particle size of 0.3-0.6 mm.

[0010] The separation adsorbent of the present invention comprises a modified type A molecular sieve with small crystal size and bimetallic salt active components. This separation adsorbent has improved ethylene adsorption capacity and adsorption selectivity, and good stability, and is not easily affected by ambient gases during use.

[0011] To achieve the above objectives, a second aspect of this application provides the application of the aforementioned separating adsorbent, characterized in that it includes: selectively adsorbing a mixed gas containing ethylene and ethane with the separating adsorbent under adsorption conditions; and desorbing ethylene from the separating adsorbent under desorption conditions.

[0012] In some implementations, the application includes the following steps:

[0013] S1) Activate the separation adsorbent of the present invention described above;

[0014] S2) Selective adsorption is achieved by contacting a bed of activated separation adsorbent with a mixed gas of ethylene and ethane at an adsorption temperature of 10-40℃ and an adsorption pressure of 0.3-1.0 MPa, preferably 0.5-0.8 MPa; the mass hourly space velocity (HSV) of the mixed gas of ethylene and ethane is 0.3-3 h⁻¹. -1 ;

[0015] S3) Desorb ethylene from the separation adsorbent at a temperature of 80-200℃ and a desorption pressure of 0.001-0.1MPa, preferably 0.005-0.08MPa.

[0016] In some embodiments, the activation temperature in step S1 is 150-550°C, preferably 200-500°C, the activation time is 30-180 min, preferably 60-150 min, and the activation is carried out in an atmosphere of nitrogen, argon, or helium.

[0017] In some embodiments, the contact between the ethylene and ethane mixture in step S2 and the bed of activated separation adsorbent is carried out in a fixed bed or a moving bed.

[0018] The separation adsorbent provided by this invention can separate high concentrations of ethylene gas from a mixture of ethylene and ethane, which can be used to produce high-value chemical raw materials. Moreover, this application can be carried out at lower temperatures and pressures, with simple operation, low industrial operating costs, and low energy consumption, and has strong industrial application prospects. Attached Figure Description

[0019] Figure 1 This is a scanning electron microscope image of the modified type A molecular sieve in Example 1. Detailed Implementation

[0020] The following details the ethylene-ethane separation adsorbent of this application, its preparation method, and the method for using the adsorbent to concentrate ethylene. However, unnecessary details may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0021] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0022] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0023] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0024] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0025] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, the condition "A or B" is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0026] Adsorption separation utilizes adsorbents to separate ethylene and ethane at room temperature and pressure. It offers advantages such as low energy consumption, low cost, and simple operation, making it a promising candidate for industrial applications. The core of adsorption separation is the adsorbent; an ideal adsorbent should possess characteristics such as high adsorption capacity, high selectivity, and long service life.

[0027] The separation adsorbent provided by this invention is characterized by comprising a modified type A molecular sieve and a support; the modified type A molecular sieve comprises a type A molecular sieve and a metal salt active component for modification, wherein the metal salt active component for modification comprises component M1 and component M2, and component M1 is selected from Mg. 2+ Ca 2+ and Sr 2+ At least one of the metal salts, wherein component M2 is selected from Fe 2+ Fe 3+ Co 2+ and Ni 2+ The modified type A molecular sieve comprises 90-97 wt% and the support comprises 3-10 wt% based on the separation adsorbent; or the modified type A molecular sieve comprises 64.0-92.0 wt%, the active component of the modified metal salt comprises 8.0-36.0 wt%, component M1 comprises 1.5-30.0 wt%, and component M2 comprises 1.5-8.0 wt%.

[0028] In some embodiments, the amount of component M1 in the modified type A molecular sieve is 5.0-26.0 wt%, and the amount of component M2 is 1.6-7.5 wt%, based on the weight of the modified type A molecular sieve.

[0029] In the modified type A molecular sieve, the loading amounts of components M1 and M2 are obtained by X-ray fluorescence spectroscopy. For example, this can be determined using a Rigaku ZSX100E X-ray fluorescence spectrometer with a tube voltage of 40 kV and a tube current of 250 mA, utilizing the proportionality between the intensity of the fluorescence rays of each element and its concentration for elemental analysis. For example, in one embodiment, the loading amount of component M1 in the modified type A molecular sieve is 18.6 wt%, and the loading amount of component M2 is 1.68 wt%, based on the weight of the modified type A molecular sieve.

[0030] In some embodiments, the average grain size of the modified type A molecular sieve is not greater than 1.0 μm, preferably not greater than 0.9 μm, and more preferably 0.70-0.85 μm.

[0031] The average grain size of the modified type A molecular sieve was obtained by observation and statistical analysis using a scanning electron microscope (SEM). For example, it could be measured using a Hitachi S4800 SEM from Japan, with an accelerating voltage of 5 kV, a working distance of 8 mm, and a magnification of 5 k to 50 k. The size of each grain was measured according to the scale bar on the image, with at least 100 grains measured, and then statistically analyzed. For example, in one embodiment, the average grain size of the modified type A molecular sieve was 793 nm.

[0032] In some embodiments, the carrier in the separating adsorbent is at least one of kaolin, bentonite, montmorillonite, diatomaceous earth, attapulgite, and halloysite.

[0033] In the invention patent application with application number 202111239467.8 and application date of October 25, 2021, the applicant disclosed the preparation method of the modified type A molecular sieve in the separation adsorbent of the present invention, which is hereby cited as follows:

[0034] A method for preparing modified type A molecular sieves includes: a preparation step of type A molecular sieves and an ion exchange modification step.

[0035] The preparation steps of the type A molecular sieve include:

[0036] (1) Sodium hydroxide, aluminum source, silicon source and deionized water are mixed evenly at room temperature according to the molar ratio of Na2O:Al2O3:SiO2:H2O of 2.5-4.0:0.8-1.0:1.9-3.8:100-150 to obtain the initial reaction gel;

[0037] (2) The initial reaction gel described in step (1) is aged at a temperature of 25-40℃ for 4-120h to obtain a mixed solution;

[0038] (3) The mixed solution described in step (2) is crystallized under hydrothermal reaction conditions at a temperature of 50-90℃ for 2-12 hours, and after filtration, washing and drying, type A molecular sieve is obtained.

[0039] In step (1), the molar ratio of Na2O:Al2O3:SiO2:H2O of the raw materials sodium hydroxide, aluminum source, silicon source and deionized water is 2.5-4.0:0.8-1.0:1.9-3.8:100-150, preferably 2.5-3.5:0.9-1.0:1.9-2.5:110-130; the aluminum source is selected from at least one of aluminum salts, aluminates, activated alumina, alkoxyaluminum, pseudoboehmite, and boehmite, preferably at least one of aluminates and boehmite; the silicon source is selected from at least one of silica, silica sol, silica gel, water glass, activated silica, and orthosilicate, preferably at least one of tetraethyl orthosilicate, water glass, and silica sol; the above mixture is stirred at room temperature to obtain an initial reaction gel.

[0040] In step (2), the initial reaction gel is aged to obtain a mixed solution. The aging temperature is 25-40℃, preferably 30-40℃, and the aging time is 4-120h, preferably 12-72h.

[0041] In step (3), the mixed solution is crystallized in a hydrothermal reactor at a temperature of 50-90℃, preferably 70-90℃, for a time of 2-12h, preferably 4-12h. After filtration and washing, type A molecular sieve is obtained.

[0042] The ion exchange modification step can be performed in the following order:

[0043] (1) Mix the soluble salt containing component M1 with type A molecular sieve and deionized water at a mass ratio of 0.1-2.5:1:10, exchange the mixed solution at a temperature of 50-90℃ for 30-120 min, and then filter, wash and dry.

[0044] (2) Mix the soluble salt containing component M2 with the product of (1) at a mass ratio of soluble salt containing component M2, type A molecular sieve and deionized water of 0.02-0.5:1:10. Exchange the mixed solution at a temperature of 50-90℃ for 30-120 minutes, and then filter, wash and dry.

[0045] Alternatively, the ion exchange modification step is as follows:

[0046] (1) Mix the soluble salt containing component M2 with type A molecular sieve and deionized water at a mass ratio of 0.1-2.5:1:10. Exchange the mixed solution at a temperature of 50-90℃ for 30-120 min, and then filter, wash and dry.

[0047] (2) Mix the soluble salt containing component M1 with the product of (1) at a mass ratio of soluble salt containing component M1, type A molecular sieve and deionized water of 0.02-0.5:1:10. Exchange the mixed solution at a temperature of 50-90℃ for 30-120 minutes, and then filter, wash and dry.

[0048] Alternatively, the ion exchange modification step is as follows: a soluble salt containing component M1, a soluble salt containing component M2, a type A molecular sieve, and deionized water are mixed at a mass ratio of 0.1-2.5:0.1-2.5:1:10. The mixed solution is exchanged at a temperature of 50-90℃ for 30-120 minutes, and then filtered, washed, and dried.

[0049] In the ion exchange step, the soluble salt is selected from at least one of nitrates and chlorides.

[0050] Based on the preparation of the modified type A molecular sieve provided above, the separation adsorbent of the present invention is made by further mixing the modified type A molecular sieve with a carrier. For example, the modified type A molecular sieve and the carrier are mixed evenly to form a mixed powder, which is then placed in a sugar coating pan and sprayed with about 12 wt% of deionized water based on the mixed powder while rolling. The mixture is then rolled into small balls with a particle size of 0.3-0.6 mm.

[0051] The present invention further provides the application of the above-mentioned adsorption and separation agent, characterized in that it includes: selectively adsorbing a mixed gas containing ethylene and ethane with the separation and adsorption agent under adsorption conditions; and desorbing ethylene from the separation and adsorption agent under desorption conditions.

[0052] In some implementations, the application includes the following steps:

[0053] S1) Activate the separation adsorbent of the present invention described above;

[0054] S2) Selective adsorption is achieved by contacting a bed of activated separation adsorbent with a mixed gas of ethylene and ethane at an adsorption temperature of 10-40℃ and an adsorption pressure of 0.3-1.0 MPa, preferably 0.5-0.8 MPa; the mass hourly space velocity (HSV) of the mixed gas of ethylene and ethane is 0.3-3 h⁻¹. -1 ;

[0055] S3) Desorb ethylene from the separation adsorbent at a temperature of 80-200℃ and a desorption pressure of 0.001-0.1MPa, preferably 0.005-0.08MPa.

[0056] In some embodiments, the activation temperature in step S1 is 150-550°C, preferably 200-500°C, the activation time is 30-180 min, preferably 60-150 min, and the activation is carried out in an atmosphere of nitrogen, argon, or helium.

[0057] In some embodiments, the contact between the ethylene and ethane mixture in step S2 and the bed of activated separation adsorbent is carried out in a fixed bed or a moving bed.

[0058] When a mixture of ethylene and ethane is contacted with a bed of separation adsorbent for selective adsorption, the ethylene content in the tail gas after passing through the separation adsorbent bed is determined using an Agilent 7890A gas chromatograph. Selective adsorption is stopped when an ethylene signal is detectable in the tail gas, i.e., step S2 is halted. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using an Agilent 7890A gas chromatograph.

[0059] In this application, the definitions within the broadest scope and the preferred definitions can be combined to form new technical solutions, which are also considered to be disclosed in this specification.

[0060] The present application is illustrated by way of examples below, but should not be construed as limiting the scope of the present application.

[0061] Example

[0062] I. Instruments

[0063] Hydrothermal reaction equipment (KLJX-811 homogeneous reactor manufactured by Yantai Keli Chemical Equipment Co., Ltd.)

[0064] Magnetic stirring equipment (DF-101S heat-collecting magnetic heating stirrer manufactured by Jiangsu Jinyi Instrument Technology Co., Ltd.)

[0065] Vacuum filtration equipment with Buchner funnel and filtration flask (SHZ-D(III) type circulating water vacuum pump manufactured by Gongyi Yuhua Instrument Co., Ltd.).

[0066] Electric tableting equipment (DY-20 tabletop electric tableting machine manufactured by Tianjin Keqi High-Tech Co., Ltd.)

[0067] Gas quantitative detection equipment (Agilent Technologies 7890A gas chromatograph).

[0068] Adsorbent forming equipment (sugar coating machine manufactured by Guangzhou Xulang Machinery Equipment Co., Ltd.)

[0069] II. Raw Materials

[0070] All reagents used in the synthesis of type A molecular sieves were of analytical grade and purchased from Beijing Innovent Technology Co., Ltd.

[0071] All reagents used for ion exchange modification were chemically pure and purchased from Alfa Aesar, USA.

[0072] Ethylene (purity >99.99%), ethane (99.95%), and a mixture of ethylene and ethane were purchased from Beijing Helium North Branch Gas Industry Co., Ltd.

[0073] The carriers, such as kaolin, bentonite, montmorillonite, diatomite, palygorskite, and halloysite, used in the ethylene ethane separation adsorbent were purchased from Changling Branch of China Petroleum & Chemical Corporation.

[0074] III. Detection methods for modified type A molecular sieves

[0075] Chemical composition of modified type A molecular sieve: determined using a Rigaku ZSX100E X-ray fluorescence spectrometer (40kV, 250mA). Elemental analysis was performed based on the relationship that the intensity of fluorescence rays of each element is proportional to its concentration.

[0076] The average grain size of the modified type A molecular sieve was determined using a Hitachi S4800 scanning electron microscope (SEM) with an accelerating voltage of 5 kV, a working distance of 8 mm, and a magnification of 5 kV-50 kV. The size of each grain was measured according to the scale on the image, with at least 100 grains measured, and then statistically analyzed.

[0077] IV. Determination of products after ethylene concentration in a mixture of ethylene and ethane gases

[0078] The ratio of the peak areas of ethylene and ethane after desorption from the adsorbent is determined using an Agilent 7890A gas chromatograph, which is the volume ratio of ethylene to ethane.

[0079] Example 1

[0080] 1) Preparation of modified type A molecular sieves

[0081] Add 1.81g NaOH, 1.35g sodium aluminate, and 8g water glass (SiO2 251.5g / L, Na2O 176.65g / L) to 33.0mL of deionized water, stir to obtain a mixed gel, transfer to a high-pressure hydrothermal reactor, age at 30℃ for 36h, after aging, raise the temperature to 70℃ and crystallize for 10h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100℃ to obtain 4A molecular sieve; weigh 4g of the obtained 4A molecular sieve, mix with 3g anhydrous CaCl2 and 40g deionized water, perform ion exchange at 80℃ for 60min, then filter, wash with deionized water until neutral, and dry at 100℃; weigh another 4g of the dried sample, and mix with 0.366g... Ni(NO3)2·6H2O and 40g of deionized water were mixed and subjected to ion exchange at 80℃ for 60min. The mixture was then filtered and washed with deionized water until neutral. Finally, it was dried at 100℃ to obtain the modified type A molecular sieve. The average grain size of the modified type A molecular sieve was 793nm. Its scanning electron microscope image is shown below. Figure 1 .

[0082] 2) Preparation of ethylene-ethane separation adsorbent

[0083] The modified type A molecular sieve and kaolin were mixed evenly at a mass ratio of 95:5 to form a mixed powder. The powder was placed in a sugar coating pan and 12wt% deionized water was sprayed in while rolling. Based on the weight of the mixed powder, it was then rolled into small balls with a particle size of 0.3-0.6mm.

[0084] 3) Concentrating ethylene from a mixture of ethylene and ethane gases

[0085] The above-mentioned ethylene-ethane separation adsorbent was activated at 450℃ under a nitrogen atmosphere for 30 min. Then, a mixture of ethylene and ethane with a volume ratio of 20:80 was introduced at 10℃ and 0.8 MPa for 0.6 h. -1 Selective adsorption was achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method was a moving bed. Selective adsorption was stopped when ethylene was detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature was then raised to 80°C and the pressure reduced to 0.001 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The ethylene / ethane volume ratio of the desorbed ethylene and ethane was determined using a 7890A gas chromatograph. The results are shown in Table 1.

[0086] Example 2

[0087] Modified type A molecular sieves were prepared using the same conditions as in Example 1.

[0088] The ethylene ethane separation adsorbent was prepared according to the method in Example 1, except that the carrier was montmorillonite and the mass ratio of modified type A molecular sieve to montmorillonite was 93:7.

[0089] The ethylene-ethane separation adsorbent was activated at 400℃ under an argon atmosphere for 60 min, and then a mixture of ethylene and ethane at a volume ratio of 26:74 was introduced at 20℃ and 0.6 MPa for 1.2 h. -1 Selective adsorption is achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method is a fixed bed. Selective adsorption is stopped when ethylene is detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature is then raised to 100°C and the pressure is reduced to 0.01 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using a 7890A gas chromatograph. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0090] Example 3

[0091] Modified type A molecular sieves were prepared using the same conditions as in Example 1.

[0092] The ethylene ethane separation adsorbent was prepared according to the method in Example 1, except that the carrier was diatomaceous earth and the mass ratio of modified type A molecular sieve to diatomaceous earth was 92:8.

[0093] The ethylene-ethane separation adsorbent was activated at 150℃ under a nitrogen atmosphere for 180 min, and then a mixture of ethylene and ethane at a volume ratio of 1:99 was introduced at 32℃ and 0.4 MPa for 3.0 h. -1 Selective adsorption is achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method is a fixed bed. Selective adsorption is stopped when ethylene is detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature is then raised to 160°C and the pressure is reduced to 0.02 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using a 7890A gas chromatograph. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0094] Example 4

[0095] Modified type A molecular sieves were prepared using the same conditions as in Example 1.

[0096] The ethylene ethane separation adsorbent was prepared according to the method in Example 1, except that the carrier was kaolin and the mass ratio of modified type A molecular sieve to kaolin was 95:5.

[0097] The ethylene-ethane separation adsorbent was activated at 250℃ under a helium atmosphere for 120 min, and then a mixture of ethylene and ethane at a volume ratio of 15:85 was introduced at 25℃ and 1.0 MPa for 2.7 h. -1 Selective adsorption is achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method is a fixed bed. Selective adsorption is stopped when ethylene is detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature is then raised to 140°C and the pressure is reduced to 0.06 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using a 7890A gas chromatograph. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0098] Example 5

[0099] Modified type A molecular sieves were prepared using the same conditions as in Example 1.

[0100] The ethylene ethane separation adsorbent was prepared according to the method in Example 1, except that the carrier was diatomaceous earth and the mass ratio of modified type A molecular sieve to diatomaceous earth was 90:10.

[0101] The ethylene-ethane separation adsorbent was activated at 500℃ under an argon atmosphere for 75 min, and then a mixture of ethylene and ethane (volume ratio 38:62) was introduced at 26℃ and 0.5 MPa for 2.4 h. -1Selective adsorption is achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method is a fixed bed. Selective adsorption is stopped when ethylene is detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature is then raised to 120°C and the pressure is reduced to 0.05 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using a 7890A gas chromatograph. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0102] Example 6

[0103] Modified type A molecular sieves were prepared using the same conditions as in Example 1.

[0104] The ethylene ethane separation adsorbent was prepared according to the method in Example 1, except that the carrier was montmorillonite and the mass ratio of modified type A molecular sieve to montmorillonite was 97:3.

[0105] The ethylene-ethane separation adsorbent was activated at 300℃ under a nitrogen atmosphere for 135 min, and then a mixture of ethylene and ethane at a volume ratio of 45:55 was introduced at 40℃ and 0.6 MPa for 0.9 h. -1 Selective adsorption is achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method is a fixed bed. Selective adsorption is stopped when ethylene is detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature is then raised to 200°C and the pressure is reduced to 0.005 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using a 7890A gas chromatograph. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0106] Example 7

[0107] Modified type A molecular sieves were prepared using the same conditions as in Example 1.

[0108] The ethylene ethane separation adsorbent was prepared according to the method in Example 1, except that the carrier was kaolin and the mass ratio of modified type A molecular sieve to kaolin was 96:4.

[0109] The ethylene-ethane separation adsorbent was activated at 550℃ under a helium atmosphere for 30 min, and then a mixture of ethylene and ethane at a volume ratio of 10:90 was introduced at 15℃ and 0.3 MPa for 2.1 h. -1Selective adsorption is achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method is a moving bed. Selective adsorption is stopped when ethylene is detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature is then raised to 100°C and the pressure is reduced to 0.1 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using a 7890A gas chromatograph. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0110] Example 8

[0111] Modified type A molecular sieves were prepared using the same conditions as in Example 1.

[0112] The ethylene ethane separation adsorbent was prepared according to the method in Example 1, except that the carrier was bentonite and the mass ratio of modified type A molecular sieve to bentonite was 92:8.

[0113] The ethylene-ethane separation adsorbent was activated at 250℃ under a nitrogen atmosphere for 105 min, and then a mixture of ethylene and ethane at a volume ratio of 34:66 was introduced at 30℃ and 0.7 MPa for 1.8 h. -1 Selective adsorption is achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method is a fixed bed. Selective adsorption is stopped when ethylene is detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature is then raised to 180°C and the pressure is reduced to 0.04 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using a 7890A gas chromatograph. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0114] Example 9

[0115] Modified type A molecular sieves were prepared using the same conditions as in Example 1.

[0116] The ethylene ethane separation adsorbent was prepared according to the method in Example 1, except that the carrier was kaolin and the mass ratio of modified type A molecular sieve to kaolin was 94:6.

[0117] The ethylene-ethane separation adsorbent was activated at 200℃ under an argon atmosphere for 150 min, and then a mixture of ethylene and ethane at a volume ratio of 40:60 was introduced at 28℃ and 0.8 MPa for 1.5 h. -1Selective adsorption is achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method is a fixed bed. Selective adsorption is stopped when ethylene is detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature is then raised to 160°C and the pressure is reduced to 0.08 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using a 7890A gas chromatograph. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0118] Example 10

[0119] Modified type A molecular sieves were prepared using the same conditions as in Example 1.

[0120] The ethylene ethane separation adsorbent was prepared according to the method in Example 1, except that the carrier was kaolin and the mass ratio of modified type A molecular sieve to kaolin was 91:9.

[0121] The ethylene-ethane separation adsorbent was activated at 350℃ under a helium atmosphere for 90 min, and then a mixture of ethylene and ethane (volume ratio 50:50) was introduced at 35℃ and 0.7 MPa for 0.3 h. -1 Selective adsorption is achieved by contacting the ethylene-ethane separation adsorbent bed with the adsorbent at a mass hourly space velocity (MHSV). The contact method is a fixed bed. Selective adsorption is stopped when ethylene is detectable by gas chromatography in the tail gas after passing through the ethylene-ethane separation adsorbent bed. The temperature is then raised to 180°C and the pressure is reduced to 0.07 MPa to desorb ethylene (and a small amount of ethane) from the adsorbent. The volume ratio of ethylene to ethane after desorption from the ethylene-ethane separation adsorbent is determined using a 7890A gas chromatograph. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0122] Example 11

[0123] Add 2.47 g NaOH, 1.68 g boehmite, and 8 g water glass (SiO2 251.5 g / L, Na2O 176.65 g / L) to 33.0 mL of deionized water, stir to obtain a mixed gel, transfer to a high-pressure hydrothermal reactor, age at 30 °C for 72 h, after aging, raise the temperature to 90 °C and crystallize for 4 h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100 °C to obtain 4A molecular sieve; weigh 4 g of the obtained 4A molecular sieve, mix with 9.24 g Mg(NO3)2·6H2O and 40 g deionized water, perform ion exchange at 80 °C for 60 min, then filter, wash with deionized water until neutral, and dry at 100 °C; weigh 4 g of the dried sample, and mix with 1.097 g of... Ni(NO3)2·6H2O and 40g of deionized water were mixed and subjected to ion exchange at 80℃ for 60min. The mixture was then filtered and washed with deionized water until neutral. Finally, it was dried at 100℃ to obtain the modified type A molecular sieve. The average grain size of the modified type A molecular sieve was 848nm.

[0124] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0125] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0126] Example 12

[0127] Add 3.5g NaOH, 1.35g sodium aluminate, and 1.88g solid silica gel to 38.5mL of deionized water, stir to obtain a mixed gel, transfer to a high-pressure hydrothermal reactor, age at 30℃ for 72h, after aging, raise the temperature to 80℃ and crystallize for 6h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100℃ to obtain 4A molecular sieve; weigh 4g of the obtained 4A molecular sieve, mix with 3g anhydrous CaCl2 and 40g deionized water, perform ion exchange at 80℃ for 60min, then filter and wash with deionized water until neutral, and dry at 100℃; weigh another 4g of the dried sample, mix with 0.25g FeCl2·4H2O and 40g deionized water, perform ion exchange at 80℃ for 60min, then filter and wash with deionized water until neutral, and dry at 100℃ to obtain modified type A molecular sieve. The average grain size of the modified type A molecular sieve is 877 nm.

[0128] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0129] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0130] Example 13

[0131] Add 2.47 g NaOH, 3.36 g aluminum isopropoxide, and 8 g water glass (SiO2 251.5 g / L, Na2O 176.65 g / L) to 33.0 mL of deionized water, stir to obtain a mixed gel, transfer to a high-pressure hydrothermal reactor, age at 25 °C for 4 h, after aging, raise the temperature to 80 °C and crystallize for 12 h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100 °C to obtain 4A molecular sieve; weigh 4 g of the obtained 4A molecular sieve, mix with 9.69 g SrCl2·6H2O and 40 g deionized water, perform ion exchange at 80 °C for 60 min, then filter, wash with deionized water until neutral, and dry at 100 °C; weigh another 4 g of the dried sample, and mix with 1.197 g of... CoCl2·6H2O was mixed with 40g of deionized water and subjected to ion exchange at 80℃ for 60min. The mixture was then filtered and washed with deionized water until neutral. Finally, it was dried at 100℃ to obtain the modified type A molecular sieve. The average grain size of the modified type A molecular sieve was 596nm.

[0132] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0133] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0134] Example 14

[0135] Add 5.27g NaOH, 3.36g aluminum isopropoxide, and 13.02g tetraethyl orthosilicate to 44.5mL of deionized water, stir to obtain a mixed gel, transfer to an autoclave, age at 40℃ for 24h, after aging, raise the temperature to 90℃ and crystallize for 12h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100℃ to obtain 4A molecular sieve; weigh 4g of the obtained 4A molecular sieve, mix with 1.36g FeCl3·6H2O and 40g deionized water, perform ion exchange at 80℃ for 60min, then filter, wash with deionized water until neutral, and dry at 100℃; weigh 4g of the dried sample, and mix with 1.16g... Mg(NO3)2·6H2O was mixed with 40g of deionized water and subjected to ion exchange at 80℃ for 60min. The mixture was then filtered and washed with deionized water until neutral. Finally, it was dried at 100℃ to obtain modified type A molecular sieve. The average grain size of the modified type A molecular sieve was 754nm.

[0136] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0137] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0138] Example 15

[0139] Add 3.29 g NaOH, 1.34 g boehmite, and 1.88 g solid silica gel to 41.5 mL of deionized water, stir to obtain a mixed gel, transfer to a high-pressure hydrothermal reactor, age at 30 °C for 96 h, after aging, raise the temperature to 70 °C and crystallize for 2 h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100 °C to obtain 4A molecular sieve; weigh 4 g of the obtained 4A molecular sieve, mix with 3 g anhydrous CaCl2 and 40 g deionized water, perform ion exchange at 80 °C for 60 min, then filter and wash with deionized water until neutral, and dry at 100 °C; weigh another 4 g of the dried sample, mix with 0.125 g FeCl2·4H2O and 40 g deionized water, perform ion exchange at 80 °C for 60 min, then filter and wash with deionized water until neutral, and dry at 100 °C to obtain modified type A molecular sieve. The average grain size of the modified type A molecular sieve is 469 nm.

[0140] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0141] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0142] Example 16

[0143] Add 3.95g NaOH, 1.52g boehmite, and 7.54g tetraethyl orthosilicate to 38.5mL of deionized water, stir to obtain a mixed gel, transfer to an autoclave, age at 40℃ for 24h, after aging, raise the temperature to 60℃ and crystallize for 10h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100℃ to obtain 4A molecular sieve; weigh 4g of the obtained 4A molecular sieve, mix with 2g anhydrous CaCl2 and 40g deionized water, perform ion exchange at 80℃ for 60min, then filter, wash with deionized water until neutral, and dry at 100℃; weigh another 4g of the dried sample, and mix with 0.366g... Ni(NO3)2·6H2O and 40g of deionized water were mixed and subjected to ion exchange at 80℃ for 60min. The mixture was then filtered and washed with deionized water until neutral. Finally, it was dried at 100℃ to obtain the modified type A molecular sieve. The average grain size of the modified type A molecular sieve was 716nm.

[0144] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0145] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0146] Example 17

[0147] 1.07 g NaOH, 1.08 g sodium aluminate, and 8 g water glass (SiO2 251.5 g / L, Na2O 176.65 g / L) were added to 35.9 mL of deionized water and stirred to obtain a mixed gel. The gel was transferred to a high-pressure hydrothermal reactor and aged at 30 °C for 96 h. After aging, the temperature was raised to 70 °C and crystallized for 8 h. The resulting hydrothermal reaction product was filtered, washed with deionized water until neutral, and dried at 100 °C to obtain 4A molecular sieve. 4 g of the obtained 4A molecular sieve was weighed and mixed with 4.620 g anhydrous CaCl2, 0.731 g Ni(NO3)2·6H2O, and 40 g deionized water. Ion exchange was performed in an 80 °C water bath for 60 min, followed by filtration and washing with deionized water until neutral. The mixture was then dried at 100 °C to obtain modified type A molecular sieve. The average grain size of the modified type A molecular sieve was 841 nm.

[0148] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0149] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0150] Example 18

[0151] Add 4.74 g NaOH, 1.08 g sodium aluminate, and 1.88 g solid silica gel to 44.5 mL of deionized water, stir to obtain a mixed gel, transfer to an autoclave, age at 30 °C for 120 h, after aging to 50 °C for 12 h, then crystallize at 50 °C, filter the resulting hydrothermal reaction product, wash with deionized water until neutral, and dry at 100 °C to obtain 4A molecular sieve; weigh 4 g of the obtained 4A molecular sieve, mix with 9.69 g SrCl2·6H2O and 40 g deionized water, perform ion exchange at 80 °C for 60 min, then filter, wash with deionized water until neutral, and dry at 100 °C; weigh 4 g of the dried sample, and mix with 0.75 g of... FeCl2·4H2O was mixed with 40g of deionized water and subjected to ion exchange at 80℃ for 60min. The mixture was then filtered and washed with deionized water until neutral. Finally, it was dried at 100℃ to obtain the modified type A molecular sieve. The average grain size of the modified type A molecular sieve was 749nm.

[0152] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0153] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0154] Example 19

[0155] Add 4.61g NaOH, 1.35g sodium aluminate, and 11.98g tetraethyl orthosilicate to 29.6mL of deionized water, stir to obtain a mixed gel, transfer to an autoclave, age at 40℃ for 12h, after aging to 60℃ for 12h, then crystallize. Filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100℃ to obtain 4A molecular sieve. Weigh 4g of the obtained 4A molecular sieve, mix with 4.84g SrCl2·6H2O and 40g deionized water, and perform ion exchange at 80℃ for 60min. Filter, wash with deionized water until neutral, and dry at 100℃. Weigh 4g of the dried sample and mix with 1.463g... Ni(NO3)2·6H2O was mixed with 40g of deionized water and subjected to ion exchange at 80℃ for 60min. The mixture was then filtered and washed with deionized water until neutral. Finally, it was dried at 100℃ to obtain the modified type A molecular sieve. The average grain size of the modified type A molecular sieve was 663nm.

[0156] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0157] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0158] Comparative Example 1

[0159] 1.81 g NaOH, 1.35 g sodium aluminate, and 8 g water glass (SiO2 251.5 g / L, Na2O 176.65 g / L) were added to 33.0 mL of deionized water and stirred to obtain a mixed gel. The gel was transferred to a high-pressure hydrothermal reactor and aged at 30 °C for 36 h. After aging, the temperature was raised to 70 °C and crystallized for 10 h. The obtained hydrothermal reaction product was filtered, washed with deionized water until neutral, and dried at 100 °C to obtain 4A molecular sieve.

[0160] The ethylene ethane separation adsorbent was prepared according to the method in Example 9.

[0161] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 9. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0162] Comparative Example 2

[0163] 1.81 g NaOH, 1.35 g sodium aluminate, and 8 g water glass (SiO2 251.5 g / L, Na2O 176.65 g / L) were added to 33.0 mL of deionized water and stirred to obtain a mixed gel. The gel was transferred to a high-pressure hydrothermal reactor and aged at 30 °C for 36 h. After aging, the temperature was raised to 70 °C and crystallized for 10 h. The resulting hydrothermal reaction product was filtered, washed with deionized water until neutral, and dried at 100 °C to obtain 4A molecular sieve. 4 g of the obtained 4A molecular sieve was weighed and mixed with 3 g anhydrous CaCl2 and 40 g deionized water. Ion exchange was carried out in an 80 °C water bath for 60 min. The mixture was then filtered, washed with deionized water until neutral, and dried at 100 °C to obtain modified type A molecular sieve.

[0164] The ethylene ethane separation adsorbent was prepared according to the method in Example 9.

[0165] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 9. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0166] Comparative Example 3

[0167] 1.81 g NaOH, 1.35 g sodium aluminate, and 8 g water glass (SiO2 251.5 g / L, Na2O 176.65 g / L) were added to 33.0 mL of deionized water and stirred to obtain a mixed gel. The gel was transferred to a high-pressure hydrothermal reactor and aged at 30 °C for 36 h. After aging, the temperature was raised to 70 °C and crystallized for 10 h. The hydrothermal reaction product was filtered, washed with deionized water until neutral, and dried at 100 °C to obtain 4A molecular sieve. 4 g of the obtained 4A molecular sieve was weighed and mixed with 0.366 g Ni(NO3)2·6H2O and 40 g deionized water. Ion exchange was performed at 80 °C for 60 min. The mixture was then filtered, washed with deionized water until neutral, and dried at 100 °C to obtain modified type A molecular sieve.

[0168] The ethylene ethane separation adsorbent was prepared according to the method in Example 9.

[0169] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 9. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0170] Comparative Example 4

[0171] 2.47 g NaOH, 3.36 g aluminum isopropoxide, and 8 g water glass (SiO2 251.5 g / L, Na2O 176.65 g / L) were added to 33.0 mL of deionized water and stirred to obtain a mixed gel. The gel was transferred to a high-pressure hydrothermal reactor and aged at 25 °C for 4 h. After aging, the temperature was raised to 80 °C and crystallized for 12 h. The obtained hydrothermal reaction product was filtered, washed with deionized water until neutral, and dried at 100 °C to obtain 4A molecular sieve.

[0172] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0173] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0174] Comparative Example 5

[0175] 2.47 g NaOH, 3.36 g aluminum isopropoxide, and 8 g water glass (SiO2 251.5 g / L, Na2O 176.65 g / L) were added to 33.0 mL of deionized water and stirred to obtain a mixed gel. The gel was transferred to a high-pressure hydrothermal reactor and aged at 25 °C for 4 h. After aging, the temperature was raised to 80 °C and crystallized for 12 h. The hydrothermal reaction product was filtered, washed with deionized water until neutral, and dried at 100 °C to obtain 4A molecular sieve. 4 g of the obtained 4A molecular sieve was weighed and mixed with 9.69 g SrCl2·6H2O and 40 g deionized water. Ion exchange was carried out in an 80 °C water bath for 60 min. The mixture was then filtered, washed with deionized water until neutral, and dried at 100 °C to obtain modified type A molecular sieve.

[0176] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0177] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0178] Comparative Example 6

[0179] 2.47 g NaOH, 3.36 g aluminum isopropoxide, and 8 g water glass (SiO2 251.5 g / L, Na2O 176.65 g / L) were added to 33.0 mL of deionized water and stirred to obtain a mixed gel. The gel was transferred to a high-pressure hydrothermal reactor and aged at 25 °C for 4 h. After aging, the temperature was raised to 80 °C and crystallized for 12 h. The resulting hydrothermal reaction product was filtered, washed with deionized water until neutral, and dried at 100 °C to obtain 4A molecular sieve. 4 g of the obtained 4A molecular sieve was weighed and mixed with 1.197 g CoCl2·6H2O and 40 g deionized water. Ion exchange was performed at 80 °C for 60 min, followed by filtration and washing with deionized water until neutral. The mixture was then dried at 100 °C to obtain modified type A molecular sieve. The average grain size of the modified type A molecular sieve was 596 nm.

[0180] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0181] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0182] Comparative Example 7

[0183] Add 3.29 g NaOH, 1.34 g boehmite and 1.88 g solid silica gel to 41.5 mL of deionized water, stir to obtain a mixed gel, transfer to a high-pressure hydrothermal reactor, age at 30 °C for 96 h, after aging, raise the temperature to 70 °C and crystallize for 2 h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100 °C to obtain 4A molecular sieve.

[0184] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0185] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0186] Comparative Example 8

[0187] Add 3.29 g NaOH, 1.34 g boehmite, and 1.88 g solid silica gel to 41.5 mL of deionized water, stir to obtain a mixed gel, transfer to a high-pressure hydrothermal reactor, age at 30 °C for 96 h, after aging, raise the temperature to 70 °C and crystallize for 2 h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100 °C to obtain 4A molecular sieve; weigh 4 g of the obtained 4A molecular sieve, mix with 3 g anhydrous CaCl2 and 40 g deionized water, perform ion exchange at 80 °C for 60 min, then filter and wash with deionized water until neutral, and dry at 100 °C to obtain modified type A molecular sieve.

[0188] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0189] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0190] Comparative Example 9

[0191] Add 3.29 g NaOH, 1.34 g boehmite, and 1.88 g solid silica gel to 41.5 mL of deionized water, stir to obtain a mixed gel, transfer to a high-pressure hydrothermal reactor, age at 30 °C for 96 h, after aging, raise the temperature to 70 °C and crystallize for 2 h, filter the obtained hydrothermal reaction product, wash with deionized water until neutral, and dry at 100 °C to obtain 4A molecular sieve; weigh 4 g of the obtained 4A molecular sieve, mix with 0.125 g FeCl2·4H2O and 40 g deionized water, perform ion exchange at 80 °C for 60 min, then filter and wash with deionized water until neutral, and dry at 100 °C to obtain modified type A molecular sieve.

[0192] The ethylene ethane separation adsorbent was prepared according to the method in Example 8.

[0193] Ethylene was concentrated from a mixture of ethylene and ethane gas according to the method described in Example 8. The volume ratio of ethylene to ethane in the product is shown in Table 1.

[0194] As shown in Table 1, compared with the ethylene / ethane volume ratio in the raw material, the ethylene concentration method of this application can increase the ethylene / ethane volume ratio in the product to over 72:28, resulting in an ethylene concentration increase of at least 76% relative to the raw material's ethylene / ethane volume ratio. Compared with the ethylene-ethane separation adsorbents in the comparative examples that contain no active component, only active component M1, or only active component M2, the ethylene concentration in the product can be increased by at least 5 percentage points using the ethylene-ethane separation adsorbent of this application. Therefore, the ethylene concentration obtained by the ethylene concentration method of this application is high, the operation process is simple, energy consumption is low, and industrial operating costs are low, showing strong industrial application prospects.

[0195] Table 1

[0196]

Claims

1. An ethylene-ethane separation adsorbent, characterized in that, The invention includes a modified type A molecular sieve and a support; the modified type A molecular sieve comprises a type A molecular sieve and a metal salt active component for modification, wherein the metal salt active component for modification comprises component M1 and component M2, and component M1 is selected from Mg. 2+ Ca 2+ and Sr 2+ At least one of the metal salts, wherein component M2 is Fe 2+ The metal salt; wherein, based on the separation adsorbent, the modified type A molecular sieve is 90-97 wt%, and the support is 3-10 wt%; based on the modified type A molecular sieve, the type A molecular sieve is 64.0-92.0 wt%, the active component of the metal salt used for modification is 8.0-36.0 wt%, component M1 is 1.5-30.0 wt%, and component M2 is 1.5-8.0 wt%.

2. The separation adsorbent according to claim 1, characterized in that, The component M1 is 5.0-26.0 wt%, and the component M2 is 1.6-7.5 wt%.

3. The separation adsorbent according to claim 1, characterized in that, The average grain size of the modified type A molecular sieve is no greater than 1 μm.

4. The separation adsorbent according to claim 3, characterized in that, The modified type A molecular sieve has an average grain size of no more than 0.9 μm.

5. The separation adsorbent according to claim 3, characterized in that, The modified type A molecular sieve has an average grain size of 0.70-0.85 μm.

6. The separation adsorbent according to claim 1, characterized in that, The carrier is selected from at least one of kaolin, bentonite, montmorillonite, diatomite, rettoite, and halloysite.

7. The separation adsorbent according to claim 1, characterized in that, The separation adsorbent is a molded microsphere with a particle size of 0.3-0.6 mm.

8. The application of the separating adsorbent according to any one of claims 1-7, characterized in that, include: Under adsorption conditions, a mixed gas containing ethylene and ethane is contacted with the separation adsorbent to achieve selective adsorption. Ethylene is desorbed from the separating adsorbent under desorption conditions.

9. The application according to claim 8, characterized in that... Includes the following steps: S1) Activate the separation adsorbent according to any one of claims 1-7; S2) Selective adsorption is achieved by contacting a bed of activated separation adsorbent with a mixed gas of ethylene and ethane at an adsorption temperature of 10-40℃ and an adsorption pressure of 0.3-1.0 MPa; the mass hourly space velocity (HSV) of the mixed gas of ethylene and ethane is 0.3-3 h⁻¹. -1 ; S3) Desorbs ethylene from the separation adsorbent at a temperature of 80-200℃ and a pressure of 0.001-0.1MPa.

10. The application according to claim 9, characterized in that, The adsorption pressure is 0.5-0.8 MPa.

11. The application according to claim 9, characterized in that, The desorption pressure is 0.005-0.08 MPa.

12. The application according to claim 9, characterized in that, The activation described in step S1 is performed at a temperature of 150-550℃ for 30-180 min, and the activation is carried out in an atmosphere of nitrogen, argon or helium.

13. The application according to claim 12, characterized in that, The activation described in step S1 is performed under the following conditions: temperature 200-500℃, time 60-150 min.

14. The application according to claim 9, characterized in that, Step S2 is performed on a fixed bed or a movable bed.

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