CN111018648A

CN111018648A - Method for producing 1-butene by isomerizing 2-butene

Info

Publication number: CN111018648A
Application number: CN201811175345.5A
Authority: CN
Inventors: 龚海燕; 刘俊涛; 钟源
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2018-10-10
Filing date: 2018-10-10
Publication date: 2020-04-17

Abstract

The invention relates to a method for producing 1-butene by isomerizing 2-butene. The method comprises the following steps: a) feeding a feed stream containing 2-butene into a first reaction zone to contact with a catalyst A to produce a stream I; b) passing said stream I to at least one second reaction zone for contact with catalyst B to produce a product stream comprising 1-butene; wherein the catalyst A contains molecular sieve Zr-ZSM with a framework of zirconium; the catalyst B contains molecular sieve Sn-ZSM with framework tin.

Description

Method for producing 1-butene by isomerizing 2-butene

Technical Field

The invention relates to a method for producing 1-butene by isomerizing 2-butene.

Background

1-butene is α -olefin with relatively active chemical property, is mainly used for producing Linear Low Density Polyethylene (LLDPE), High Density Polyethylene (HDPE), Polybutylene (PB) resin, decanol and the like, and has wide application, in recent years, the global demand for polyethylene is rapidly increased, so the demand for 1-butene serving as a comonomer is increased, however, most of domestic 1-butene manufacturers are self-used and rarely sell the 1-butene to other parts, so the purchase of the 1-butene is relatively difficult, and particularly, enterprises with relatively large gaps for the 1-butene exist.

Currently, there are two main routes for global 1-butene production, one is oligomerization process using ethylene as raw material, and the other is refinery C₄C, cracking₄Or coal-to-olefin byproduct mixed C₄Is obtained by separating raw materials. The latter is commonly adopted in China for the mixed C₄Butadiene extraction and hydrogenation are carried out, isobutene is removed through etherification, and then 1-butene products are obtained through rectification separation. But the yield of 1-butene in this route is limited by the source of 1-butene in the feed. Most petrochemical companies in the world use residual C rich in 2-butene₄Hydrocarbons are used as fuels. If the part of 2-butene is converted into 1-butene through isomerization reaction, a new path for producing the 1-butene can be opened up.

In recent years, a great deal of research and development has been carried out on the process for producing 1-butene by isomerizing 2-butene by related petrochemical companies at home and abroad. For example, CN102267853A discloses a method for producing 1-butene by isomerizing 2-butene, which adopts a surface area of 150-210 m²Taking alumina per gram as a carrier, dissolving 0.146-23.82 parts by weight of metal salt in 82-100 parts by weight of deionized water to prepare an aqueous solution, and then soaking 57 parts by weight of catalyst carrier; standing and soaking for 16-24 hours at room temperature, filtering out residual liquid, drying for 4-10 hours at the temperature of 120-160 ℃ until water is completely removed, and roasting for 1-12 hours at the temperature of 500-600 ℃ to obtain the metal composite oxide catalyst. The catalyst prepared by the method is filled in a fixed bed catalytic reactor, 2-butylene gas with the content of 85.0-99.0% passes through a catalyst bed layer, the temperature is 300-480 ℃, the pressure is 0.1-0.5 Mpa, and the gas hourly space velocity of the feed of the 2-butylene is 60-900 hours^-1Under the conditions of (1), a double bond isomerization reaction is carried out. And (3) sampling and analyzing the reacted gas at regular time, wherein the content of the 1-butene is 19.0-27.0%. When the reaction temperature is controlled to be lower (300-320 ℃), the content of isobutene serving as an impurity generated by the reaction is lower, the selectivity of 1-butene is higher, and the conversion rate is only 19%. When the reaction temperature is increased and the conversion rate is increased, the content of impurity isobutene in the product is obviously increased, particularly when the conversion rate reaches 24%, the content of isobutene reaches 0.5%, and the selectivity of 1-butene is obviously reduced.

As the isomerization of 2-butene to 1-butene is accompanied by other side reactions such as skeletal isomerization, dehydration and cracking, etc. in addition to butene double bond isomerization, the side reactions affect the selectivity of the reaction on 1-butene. Although a single type of catalyst can perform isomerization reaction under a wide range of conditions, conversion and selectivity cannot be taken into consideration when the reaction conditions are greatly changed.

Disclosure of Invention

The present inventors have assiduously studied on the basis of the prior art and, as a result, have accomplished the present invention by solving at least one of the aforementioned problems by loading catalysts having different catalytic activities in divided zones.

In particular, the invention relates to a method for producing 1-butene by isomerizing 2-butene. The method comprises the following steps:

a) feeding a feed stream containing 2-butene into a first reaction zone to contact with a catalyst A to produce a stream I;

b) passing said stream I to at least one second reaction zone for contact with catalyst B to produce a product stream comprising 1-butene;

wherein the catalyst A contains molecular sieve Zr-ZSM with a framework of zirconium; the catalyst B contains molecular sieve Sn-ZSM with framework tin.

According to one aspect of the invention, the catalyst A comprises 30-90 parts by weight of Zr-ZSM and 10-70 parts by weight of a first binder, preferably 40-80 parts by weight of Zr-ZSM and 20-60 parts by weight of the first binder, and more preferably 50-80 parts by weight of Zr-ZSM and 20-50 parts by weight of the first binder; relative to the total weight parts of the Zr-ZSM and the first binder.

According to one aspect of the invention, the Zr-ZSM molecule is selected from one of the group consisting of Zr-ZSM-5, Zr-ZSM-11, Zr-ZSM-35 and Zr-ZSM-39; preferably a mechanical mixture of at least two selected from the group consisting of Zr-ZSM-5, Zr-ZSM-11, Zr-ZSM-35 and Zr-ZSM-39; more preferably eutectic molecular sieves of at least two selected from the group consisting of Zr-ZSM-5, Zr-ZSM-11, Zr-ZSM-35 and Zr-ZSM-39; most preferred is Zr-ZSM-5/ZSM-11 eutectic molecular sieve.

According to an aspect of the present invention, the first binder is at least one selected from the group consisting of alumina and silica.

According to one aspect of the invention, in the Zr-ZSM molecular sieve, the molar ratio of silicon to zirconium is 50-1000, preferably 100-500.

According to one aspect of the invention, the catalyst B comprises 50-99 parts by weight of Sn-ZSM molecular sieve and 1-50 parts by weight of second binder, preferably 55-95 parts by weight of Sn-ZSM molecular sieve and 5-45 parts by weight of second binder; more preferably, the composite material comprises 60-90 parts of Sn-ZSM molecular sieve and 10-40 parts of second binder; relative to the total weight parts of the Sn-ZSM molecular sieve and the second binder.

According to one aspect of the invention, the Sn-ZSM molecule screens one of the group consisting of Sn-ZSM-5, Sn-ZSM-11, Sn-ZSM-35 and Sn-ZSM-39; preferably a mechanical mixture of at least two selected from the group consisting of Sn-ZSM-5, Sn-ZSM-11, Sn-ZSM-35 and Sn-ZSM-39; more preferably eutectic molecular sieves of at least two selected from the group consisting of Sn-ZSM-5, Sn-ZSM-11, Sn-ZSM-35 and Sn-ZSM-39; most preferred is Sn-ZSM-5/ZSM-11 eutectic molecular sieve.

According to an aspect of the present invention, the second binder is at least one selected from the group consisting of alumina and silica.

According to one aspect of the invention, the molar ratio of silicon to tin in the Sn-ZSM molecular sieve is 50-700, preferably 100-500.

According to an aspect of the present invention, the alkaline earth metal element or the oxide thereof is not contained in both of the catalyst a and the catalyst B.

According to an aspect of the present invention, the alkaline earth metal element is at least one selected from the group consisting of magnesium, calcium, strontium, and barium; in particular magnesium.

According to one aspect of the invention, the reaction temperature of the first reaction zone is 150-280 ℃, the reaction pressure is 0-1 MPa, and the weight space velocity is 1-20 hours^-1(ii) a The preferable reaction temperature is 180-270 ℃, the pressure is 0.5-1 MPa, and the weight space velocity is 2-10 hours^-1。

According to one aspect of the invention, the reaction temperature of the second reaction zone is 280-420 ℃, the pressure is 0-1 MPa, and the weight space velocity is 1-20 hours^-1(ii) a The preferable contact temperature is 320-400 ℃, the pressure is 0.5-1 MPa, and the weight space velocity is 2-10 hoursTime of flight^-1。

According to one aspect of the invention, the reaction temperature of the first reaction zone is lower than the reaction temperature of the second reaction zone.

According to one aspect of the invention, the stream containing 2-butene is derived from a refinery catalytic cracking unit, an ethylene plant steam cracking unit or a coal-to-olefin unit byproduct mixed C-IV stream, preferably a C-IV stream obtained by removing 1, 3-butadiene and isobutene from the refinery catalytic cracking unit, the ethylene plant steam cracking unit or the coal-to-olefin unit byproduct mixed C-IV stream.

According to one aspect of the invention, said 2-butene-containing stream is a mixture comprising 1-butene and 2-butene which does not meet thermodynamic equilibrium values.

According to one aspect of the invention, the 2-butene-containing stream has a mass concentration of 1-butene of less than 4% and a mass concentration of 2-butene of greater than 45%.

According to one aspect of the invention, the mass concentration of 1, 3-butadiene in the 2-butene-containing stream is less than 30 ppm.

According to one aspect of the invention, the weight ratio of the catalyst A to the catalyst B is 0.1 to 8:1, preferably 0.2 to 5:1, more preferably 0.5 to 4: 1.

The invention has the beneficial effects that:

according to the invention, the conversion rate of 2-butene and the selectivity of 1-butene can be simultaneously improved.

The invention is further described below by means of specific embodiments.

Detailed Description

The following describes in detail specific embodiments of the present invention. It is to be noted, however, that the scope of the present invention is not limited thereto, but is defined by the appended claims.

All publications, patent applications, patents, and other references mentioned in this specification are herein incorporated by reference in their entirety. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the present specification, including definitions, will control.

When the specification concludes with claims with the heading "known to those skilled in the art", "prior art", or the like, to derive materials, substances, methods, procedures, devices, or components, etc., it is intended that the subject matter derived from the heading encompass those conventionally used in the art at the time of filing this application, but also include those that are not currently in use, but would become known in the art to be suitable for a similar purpose.

In the context of the present specification, anything or things which are not mentioned, except where explicitly stated, are directly applicable to those known in the art without any changes. Moreover, any embodiment described herein may be freely combined with one or more other embodiments described herein, and the technical solutions or concepts resulting therefrom are considered part of the original disclosure or original disclosure of the invention, and should not be considered as new matters not disclosed or contemplated herein, unless a person skilled in the art would consider such a combination to be clearly unreasonable.

Unless otherwise expressly indicated, all percentages, parts, ratios, etc. mentioned in this specification are by weight unless otherwise not in accordance with the conventional knowledge of those skilled in the art.

Where not explicitly stated, reference to pressure within this specification is to gauge pressure.

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values 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 regarded as specifically disclosed herein.

The terms "first" and "second" in the "first binder", "second binder", "first mixture" and "second mixture" in the present invention are only named for distinguishing the catalyst a from the catalyst B, and do not have any other meanings.

It should be noted that the 2-butene double bond isomerization reaction to produce 1-butene is typically a reversible reaction, and generally the distribution of butene isomerization products is mainly controlled by thermodynamic factors. Therefore, different thermodynamic equilibrium conversions will be associated at different temperatures. Thermodynamic equilibrium conversion can be thermodynamically calculated for the reaction process by means of the Gibbs free energy minimum principle, which is well known to those skilled in the art.

The invention relates to a method for producing 1-butene by isomerizing 2-butene. The method comprises the following steps:

According to the invention, the catalyst A comprises 30-90 parts by weight of Zr-ZSM and 10-70 parts by weight of a first binder, preferably 40-80 parts by weight of Zr-ZSM and 20-60 parts by weight of the first binder, and more preferably 50-80 parts by weight of Zr-ZSM and 20-50 parts by weight of the first binder; relative to the total weight parts of the Zr-ZSM and the first binder.

According to the invention, in the Zr-ZSM molecular sieve, the molar ratio of silicon to aluminum is 50-500, preferably 100-450, and more preferably 200-400; the molar ratio of silicon to zirconium is 50 to 1000, preferably 100 to 500.

According to the present invention, the Zr-ZSM molecular sieve may be one selected from the group consisting of Zr-ZSM-5, Zr-ZSM-11, Zr-ZSM-35 and Zr-ZSM-39; or a mechanical mixture of at least two selected from the group consisting of Zr-ZSM-5, Zr-ZSM-11, Zr-ZSM-35 and Zr-ZSM-39; it may also be an eutectic molecular sieve of at least two selected from the group consisting of Zr-ZSM-5, Zr-ZSM-11, Zr-ZSM-35 and Zr-ZSM-39, preferably Zr-ZSM-5/ZSM-11 eutectic molecular sieve. The eutectic molecular sieves described herein, which may also be referred to in the art as intergrown molecular sieves, are distinguished from simple mechanical mixtures by having two or more distinct phases of intergrown materials of crystalline structure in one molecular sieve composition.

According to the present invention, the first binder is at least one selected from the group consisting of alumina and silica.

According to an embodiment of the present invention, the catalyst a does not contain an alkaline earth metal element or an oxide thereof from the viewpoint of more favorable isomerization reaction. The alkaline earth metal element is at least one selected from the group consisting of magnesium, calcium, strontium, and barium; in particular magnesium.

According to the invention, the catalyst A can be prepared by the following method. The method comprises the following steps: crystallizing a mixture (hereinafter, collectively referred to as a first mixture) comprising a template, a zirconium source, a silicon source, an aluminum source, and water to obtain a Zr-ZSM molecular sieve, and molding the Zr-ZSM molecular sieve with a first binder.

Wherein the template is at least one selected from the group consisting of tetrapropylammonium hydroxide, tetrapropylammonium bromide, n-butylamine, tetramethylethylenediamine, cyclohexylamine, n-propylamine, and hexamethyltetramine.

The zirconium source, any zirconium source conventionally used in the art for this purpose may be used, including but not limited to zirconium nitrate, zirconium oxychloride, and zirconium isopropoxide, with zirconium nitrate and zirconium oxychloride being preferred.

As the silicon source, any silicon source conventionally used in the art for this purpose can be used. Examples thereof include sodium silicate, silica sol and silicate ester. These silicon sources may be used singly or in combination in a desired ratio.

As the aluminum source, any aluminum source conventionally used in the art for this purpose can be used. Examples thereof include aluminum sol and aluminum hydroxide. These aluminum sources may be used singly or in combination in a desired ratio.

In the first mixture, the template agentThe source of zirconium (as ZrO)₂Calculated), the silicon source (in SiO)₂Calculated as Al), an aluminum source (calculated as Al)₂O₃Calculated) and water in a molar ratio of: 0.1-0.5: 0.001-0.025: 1: 0-0.08: 35-170; preferably: 0.2-0.4: 0.005-0.025: 0.005-0.06: 35-170. Preferably, the first mixture is controlled to have a pH of 4 to 9, and any acid or base conventionally used in the art for this purpose may be used therefor, such as hydrochloric acid, nitric acid, sulfuric acid, NaOH, KOH, and aqueous ammonia may be cited.

The crystallization may be performed in any manner conventionally known in the art, for example, a method of subjecting the mixture to hydrothermal crystallization under crystallization conditions may be exemplified. Crystallization may be in the presence of stirring as desired. The crystallization conditions include: the temperature is 120-200 ℃, and the time is 20-80 hours.

Preferably, an ageing step is included, carried out before crystallization, the ageing conditions including: the aging temperature is 30-75 ℃, and the aging time is 10-48 hours.

After the crystallization is completed, the Zr-ZSM molecular sieve may be separated from the obtained reaction mixture by any separation means conventionally known. The separation method includes, for example, a method of filtering, washing and drying the obtained product mixture. Here, the filtering, washing and drying may be performed in any manner conventionally known in the art. As a specific example, as the filtration, for example, the obtained product mixture may be simply filtered with suction. Examples of the washing include washing with deionized water and/or ethanol. The drying temperature is, for example, 40 to 250 ℃, preferably 60 to 150 ℃, and the drying time is, for example, 8 to 30 hours, preferably 10 to 20 hours. The drying may be carried out under normal pressure or under reduced pressure.

According to the requirement, the Zr-ZSM molecular sieve obtained by crystallization can be roasted to remove the organic template agent, the water and the like possibly existing, thereby obtaining the roasted molecular sieve. The calcination can be carried out in any manner conventionally known in the art, for example, the calcination temperature is generally 300 to 800 ℃, preferably 400 to 650 ℃, and the calcination time is generally 1 to 10 hours, preferably 3 to 6 hours. In addition, the calcination is generally carried out in an oxygen-containing atmosphere, such as air or oxygen.

And mixing the Zr-ZSM molecular sieve with a first binder, and molding to obtain the catalyst A. The catalyst a may be in the form of any molded article (e.g., a bar, a clover, etc.), and may be obtained in any manner conventionally known in the art, without particular limitation. As the first binder, any binder conventionally used in the art for this purpose may be used. For example, alumina or silica can be cited. Preferably, a pore-forming agent may be added during molding. As the porogen, any porogen conventionally used in the art for this purpose can be used. Examples thereof include sesbania powder and methyl cellulose.

The molded catalyst A may be dried and calcined as necessary. The drying may be carried out in any manner conventionally known in the art, and the drying temperature may be, for example, 40 to 250 ℃, preferably 60 to 150 ℃, and the drying time may be, for example, 8 to 30 hours, preferably 10 to 20 hours. The drying may be carried out under normal pressure or under reduced pressure. The calcination can be carried out in any manner conventionally known in the art, for example, the calcination temperature is generally 300 to 800 ℃, preferably 400 to 650 ℃, and the calcination time is generally 1 to 10 hours, preferably 3 to 6 hours. In addition, the calcination is generally carried out in an oxygen-containing atmosphere, such as air or oxygen.

In the preparation method of the catalyst a, the first mixture does not contain an alkaline earth metal source from the viewpoint of more favorable isomerization reaction. The alkaline earth metal is at least one selected from the group consisting of magnesium, calcium, strontium, and barium; in particular magnesium. The phrase "not including an alkaline earth metal source" as used herein means that the alkaline earth metal source is not intentionally or actively introduced during the production process.

According to the invention, the catalyst B comprises 50-99 parts by weight of Sn-ZSM molecular sieve and 1-50 parts by weight of second binder, preferably 55-95 parts by weight of Sn-ZSM molecular sieve and 5-45 parts by weight of second binder; more preferably, the composite material comprises 60-90 parts of Sn-ZSM molecular sieve and 10-40 parts of second binder; relative to the total weight parts of the Sn-ZSM molecular sieve and the second binder.

According to the invention, in the Sn-ZSM molecular sieve, the molar ratio of silicon to aluminum is 50-500, preferably 100-450, and more preferably 200-400; the molar ratio of Si to Sn is 50 to 700, preferably 100 to 500.

According to the present invention, the Sn-ZSM molecular sieve may be one selected from the group consisting of Sn-ZSM-5, Sn-ZSM-11, Sn-ZSM-35, and Sn-ZSM-39; or a mechanical mixture of at least two selected from the group consisting of Sn-ZSM-5, Sn-ZSM-11, Sn-ZSM-35, and Sn-ZSM-39; or may be eutectic molecular sieves of at least two selected from the group consisting of Sn-ZSM-5, Sn-ZSM-11, Sn-ZSM-35 and Sn-ZSM-39, preferably Sn-ZSM-5/ZSM-11 eutectic molecular sieves. The eutectic molecular sieves described herein, which may also be referred to in the art as intergrown molecular sieves, are distinguished from simple mechanical mixtures by having two or more distinct phases of intergrown materials of crystalline structure in one molecular sieve composition.

According to the present invention, the second binder is at least one selected from the group consisting of alumina and silica.

According to an embodiment of the present invention, the catalyst B does not contain an alkaline earth metal element or an oxide thereof from the viewpoint of more favorable isomerization reaction. The alkaline earth metal element is at least one selected from the group consisting of magnesium, calcium, strontium, and barium; in particular magnesium.

According to the invention, the catalyst B can be prepared by the following method. The method comprises the following steps: crystallizing a mixture (hereinafter, collectively referred to as a second mixture) comprising a templating agent, a tin source, a silicon source, an aluminum source, and water to obtain a Sn-ZSM molecular sieve, and molding the Sn-ZSM molecular sieve with a second binder.

The tin source may use any tin source conventionally used in the art for this purpose, including but not limited to tin nitrate, tin tetrachloride and stannous oxalate, with tin nitrate and tin tetrachloride being preferred.

As the aluminum source, any aluminum source conventionally used in the art for this purpose can be used. Examples thereof include aluminum sol, aluminum sulfate and aluminum hydroxide. These aluminum sources may be used singly or in combination in a desired ratio.

In the second mixture, the templating agent, the tin source (as SnO)₂Calculated), the silicon source (in SiO)₂Calculated as Al), an aluminum source (calculated as Al)₂O₃Calculated) and water in a molar ratio of: 0.1-0.5: 0.001-0.025: 1: 0-0.08: 35-170; preferably: 0.2-0.4: 0.005-0.025: 0.005-0.06: 35-170. Preferably, the second mixture is controlled to have a pH of 4 to 9, and any acid or base conventionally used in the art for this purpose may be used therefor, such as hydrochloric acid, nitric acid, sulfuric acid, NaOH, KOH, and aqueous ammonia may be cited.

After the crystallization is completed, the Sn-ZSM molecular sieve may be separated from the obtained reaction mixture by any separation means conventionally known. The separation method includes, for example, a method of filtering, washing and drying the obtained product mixture. Here, the filtering, washing and drying may be performed in any manner conventionally known in the art. As a specific example, as the filtration, for example, the obtained product mixture may be simply filtered with suction. Examples of the washing include washing with deionized water and/or ethanol. The drying temperature is, for example, 40 to 250 ℃, preferably 60 to 150 ℃, and the drying time is, for example, 8 to 30 hours, preferably 10 to 20 hours. The drying may be carried out under normal pressure or under reduced pressure.

If necessary, the crystallized Sn-ZSM molecular sieve may be calcined to remove the organic template and water, etc. that may be present, thereby obtaining a calcined molecular sieve. The calcination can be carried out in any manner conventionally known in the art, for example, the calcination temperature is generally 300 to 800 ℃, preferably 400 to 650 ℃, and the calcination time is generally 1 to 10 hours, preferably 3 to 6 hours. In addition, the calcination is generally carried out in an oxygen-containing atmosphere, such as air or oxygen.

And mixing the Sn-ZSM molecular sieve with a second binder, and molding to obtain the catalyst B. The catalyst B may be in the form of any molded article (e.g., a bar, a clover, etc.), and may be obtained in any manner conventionally known in the art, without particular limitation. As the second binder, any binder conventionally used in the art for this purpose can be used. For example, alumina or silica can be cited. Preferably, a pore-forming agent may be added during molding. As the porogen, any porogen conventionally used in the art for this purpose can be used. Examples thereof include sesbania powder and methyl cellulose.

The molded catalyst B may be dried and calcined as necessary. The drying may be carried out in any manner conventionally known in the art, and the drying temperature may be, for example, 40 to 250 ℃, preferably 60 to 150 ℃, and the drying time may be, for example, 8 to 30 hours, preferably 10 to 20 hours. The drying may be carried out under normal pressure or under reduced pressure. The calcination can be carried out in any manner conventionally known in the art, for example, the calcination temperature is generally 300 to 800 ℃, preferably 400 to 650 ℃, and the calcination time is generally 1 to 10 hours, preferably 3 to 6 hours. In addition, the calcination is generally carried out in an oxygen-containing atmosphere, such as air or oxygen.

In the preparation process of the catalyst B, the second mixture does not contain an alkaline earth metal source from the viewpoint of more favorable isomerization reaction. The alkaline earth metal is at least one selected from the group consisting of magnesium, calcium, strontium, and barium; in particular magnesium. The phrase "not including an alkaline earth metal source" as used herein means that the alkaline earth metal source is not intentionally or actively introduced during the production process.

According to the invention, the catalyst a contains Zr-ZSM with a framework of zirconium. The Zr skeleton can improve the acidity of the molecular sieve and ensure that the catalyst A has higher activity. According to this characteristic of the catalyst A, the first reaction zone is controlled at a lower reaction temperature. The reaction conditions of the first reaction zone include: the reaction temperature is 150-280 ℃, the reaction pressure is 0-1 MPa, and the weight space velocity is 1-20 hours^-1(ii) a The preferable reaction temperature is 180-270 ℃, the pressure is 0.5-1 MPa, and the weight space velocity is 2-10 hours^-1。

According to the invention, the catalyst B contains Sn-ZSM having a framework tin. Framework Sn may reduce the acidity of the molecular sieve. The second reaction zone is controlled at a higher reaction temperature according to this characteristic of the catalyst B. The reaction conditions of the second reaction zone include: the reaction temperature is 280-420 ℃, the pressure is 0-1 MPa, and the weight space velocity is 1-20 hours^-1(ii) a The preferable contact temperature is 320-400 ℃, the pressure is 0.5-1 MPa, and the weight space velocity is 2-10 hours^-1。

According to the invention, the weight ratio of the catalyst A to the catalyst B is 0.1-8: 1, preferably 0.2-5: 1, and more preferably 0.5-4: 1.

According to the present invention, it is particularly important to control the reaction temperature of the first reaction zone to be lower than the reaction temperature of the second reaction zone, depending on the different characteristics of the two catalysts. Because the reaction temperature of the first reaction zone is low, most of raw material 2-butylene is converted at low temperature through the high-activity catalyst A, and then the conversion rate is further improved through the reaction of the second reaction zone catalyst B at high temperature. Meanwhile, the catalyst A in the first reaction zone has relatively weak activity, so that side reactions are relatively less, and the effects of high conversion rate and high selectivity can be achieved simultaneously.

In the present invention, the composition of the catalyst was analyzed by ICP (inductively coupled plasma) and XRF (X-ray fluorescence) methods. ICP was used to test the zirconium content of the catalyst under the following test conditions: an iCAP7600Duo inductively coupled plasma emission spectrometer of American Sammer Feishell company is adopted, zirconium oxide is used as a standard sample, and the RF power of the instrument is 1.2 KW; the carrier gas flow is 0.72L/min; the flow rate of the cooling gas is 15L/min; the pump flow rate was 1.0ml/min and the analytical wavelength was 335 nm. ICP was used to test the tin content in the catalyst under the following test conditions: an iCAP7600Duo inductively coupled plasma emission spectrometer of American Sammer Feishell company is adopted, metallic tin is adopted as a standard sample, and the RF power of the instrument is 1.2 KW; the carrier gas flow is 0.72L/min; the flow rate of the cooling gas is 15L/min; the pump flow rate was 1.0ml/min and the analytical wavelength was 335 nm. XRF was used to test the content of molecular sieve in the catalyst under the following test conditions: a Rigaku ZSX100e XRF instrument is adopted, a rhodium target is used as an excitation source, the maximum power is 3600W, the tube voltage is 60KV, and the tube current is 120 mA.

The crystal phases of the catalyst A and the catalyst B are carried out on a Bruker D8 polycrystalline X-ray diffraction (XRD) instrument, a graphite monochromator is used, a Cu-Ka ray source is used (the K α 1 wavelength lambda is 0.15406nm), the scanning angle 2 theta is 5-50 degrees, and the scanning speed is 1 degree/min.

The existence form of Zr in the catalyst A is determined by adopting a Cary5000 type ultraviolet-visible spectrum (UV-vis) instrument, solid barium sulfate is taken as a reference, and the test wavelength range is 190-800. The multi-coordination zirconium in the molecular sieve framework can generate an absorption peak at the wavelength of 240-280 nm, and the absorption peak of the zirconium oxide is less than 200 nm.

The existence form of Sn of the catalyst B is measured by a Cary5000 type ultraviolet-visible spectrometer, a white board is taken as a reference, and the test wavelength range is 190-800. The multi-site tin in the molecular sieve framework can generate an absorption peak at the wavelength of 210-220 nm, while the absorption peak of non-framework tin or tin oxide is at the wavelength of 260-320 nm.

In the invention, the product composition is determined by gas chromatography, the chromatography model is Agilent 7890A, a FID detector is arranged, an FFAP capillary chromatographic column is used for separation, the temperature of the chromatographic column is programmed to be 90 ℃ initially, the chromatographic column is kept for 15 minutes, and then the temperature is increased to 220 ℃ at the speed of 15 ℃/minute and kept for 45 minutes.

The conversion X of 2-butene is calculated as:

X(_2-butene)＝(M_{Import 2-butene}-M_{Outlet 2-butene})/M_{Import 2-butene}×100％

The selectivity Y of 1-butene is calculated by the formula:

Y(_1-butene)＝M(_{Outlet 1-butene})/(M_{Import 2-butene}-M_{Outlet 2-butene})×100％

The present invention is further illustrated by the following examples.

[ example 1 ]

1) 6g of zirconium oxychloride is dissolved in isopropanol, and then the solution is added into 1000ml of ethyl orthosilicate to prepare a mixed solution I, and the mixed solution I is stirred for 50 minutes at room temperature. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 48 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z1-a. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework zirconium.

70g of the Z1-a molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst A1.

2) Tin tetrachloride (8.5 g) was dissolved in isopropanol, and then added to ethyl orthosilicate (1000 ml) to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 48 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z1-b. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework tin.

70g of the Z1-B molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst B1.

The results of the catalyst analysis are shown in Table 1.

[ example 2 ]

1) Take [ example 1 ] molecular Sieve Z1-a 70g, silica sol 75ml (containing 40% SiO)₂) Kneading with 5g sesbania powder, extruding into strips, baking at 120 ℃ for 4 hours, and baking at 500 ℃ for 4 hours to obtain the catalyst A2.

2) Take [ example 1 ] molecular Sieve Z1-b 70g, silica sol 75ml (containing 40% SiO)₂) Kneading with 5g sesbania powder, extruding into strips, baking at 120 ℃ for 4 hours, and baking at 500 ℃ for 4 hours to obtain the catalyst B2.

The results of the analytical tests are shown in Table 1.

[ example 3 ]

1) Taking 50g of Z1-a molecular sieve, 50g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder, kneading, extruding into strips, baking at 120 ℃ for 4 hours, and baking at 500 ℃ for 4 hours to obtain the catalyst A3.

2) Taking 65g of Z1-B molecular sieve, 35g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder, kneading, extruding into strips, baking at 120 ℃ for 4 hours, and baking at 500 ℃ for 4 hours to obtain the catalyst B3.

The results of the analytical tests are shown in Table 1.

[ example 4 ]

1) 42g of Z1-a molecular sieve, 58g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are taken to be kneaded, extruded into strips, baked at 120 ℃ for 4 hours and baked at 500 ℃ for 4 hours to obtain the catalyst A4.

2) The catalyst B1 from [ example 1 ] was charged to the second reaction zone.

The results of the analytical tests are shown in Table 1.

[ example 5 ]

1) 31g of Z1-a molecular sieve, 69g of alumina, 60ml of 0.5% nitric acid and 5g of sesbania powder are kneaded, extruded into strips, baked at 120 ℃ for 4 hours and baked at 500 ℃ for 4 hours to obtain the catalyst A5 in the embodiment 1.

2) 57g of the molecular sieve Z1-B, 43g of alumina, 60ml of 0.5% nitric acid and 5g of sesbania powder are kneaded, extruded into strips, baked at 120 ℃ for 4 hours and baked at 500 ℃ for 4 hours to obtain the catalyst B5 in the embodiment 1.

The results of the analytical tests are shown in Table 1.

[ example 6 ]

1) Taking 85g of Z1-a molecular sieve, 15g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder, kneading, extruding into strips, baking at 120 ℃ for 4 hours, and baking at 500 ℃ for 4 hours to obtain the catalyst A6.

2) 51g of molecular sieve Z1-B, 49g of alumina, 60ml of 0.5% nitric acid and 5g of sesbania powder are kneaded, extruded into strips, baked at 120 ℃ for 4 hours and baked at 500 ℃ for 4 hours to obtain the catalyst B6 in the embodiment 1.

The results of the analytical tests are shown in Table 1.

[ example 7 ]

1) 1g of zirconium oxychloride is dissolved in isopropanol, and then added into 1000ml of ethyl orthosilicate to prepare a mixed solution I, and the mixed solution I is stirred for 50 minutes at room temperature. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 48 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z7-a. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework zirconium.

70g of the Z7-a molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst A7.

2) Taking 85g of Z1-B molecular sieve, 15g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder, kneading, extruding into strips, baking at 120 ℃ for 4 hours, and baking at 500 ℃ for 4 hours to obtain the catalyst B7.

The results of the analytical tests are shown in Table 1.

[ example 8 ]

1) 4g of zirconium oxychloride is dissolved in isopropanol, and then the solution is added into 1000ml of ethyl orthosilicate to prepare a mixed solution I, and the mixed solution I is stirred for 50 minutes at room temperature. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 48 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z8-a. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework zirconium.

70g of the Z8-a molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst A8.

2) 4g of tin tetrachloride was dissolved in isopropanol, and then added to 1000ml of ethyl orthosilicate to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 48 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z8-b. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework tin.

70g of the Z8-B molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst B8.

The results of the analytical tests are shown in Table 1.

[ example 9 ]

1) 23g of zirconium oxychloride is dissolved in isopropanol, and then added to 1000ml of ethyl orthosilicate to prepare a mixed solution I, and the mixed solution I is stirred at room temperature for 50 minutes. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 48 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z9-a. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework zirconium.

70g of the Z9-a molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst A9.

2) 5.6g of tin tetrachloride was dissolved in isopropanol, and then added to 1000ml of ethyl orthosilicate to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 37 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z9-b. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework tin.

70g of the Z9-B molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst B9.

The results of the analytical tests are shown in Table 1.

[ example 10 ]

1) Take [ example 8 ] A8 and charge it to the first reactor.

2) 37g of tin tetrachloride was dissolved in isopropanol, and then added to 1000ml of ethyl orthosilicate to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 48 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain the molecular sieve powder. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework tin.

70g of the molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are dried for 4 hours at 120 ℃, and then the strips are roasted for 4 hours at 500 ℃, so that a catalyst B10 is obtained and is loaded into a second reactor.

The results of the analytical tests are shown in Table 1.

[ example 11 ]

1) 6g of zirconium oxychloride is dissolved in isopropanol, and then the solution is added into 1000ml of ethyl orthosilicate to prepare a mixed solution I, and the mixed solution I is stirred for 50 minutes at room temperature. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 48 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z11-a. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework zirconium.

70g of the Z11-a molecular sieve, 30g of alumina, 1g of magnesium oxide, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst A11.

2) B1 from [ example 1 ] was charged into the second reaction zone.

The results of the analytical tests are shown in Table 1.

[ example 12 ]

1) 6g of zirconium oxychloride was dissolved in isopropanol, and then added to 700ml of silica sol (containing 40% of SiO2) to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of water solution containing 8% of n-butylamine is prepared to prepare solution II. 10g of aluminum hydroxide was added to the solution II with stirring to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 50 hours at the temperature of 165 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z12 a-1. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5 type molecular sieve containing framework zirconium.

6g of zirconium oxychloride was dissolved in isopropanol, and then added to 700ml of silica sol (containing 40% of SiO2) to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of an aqueous solution containing 8% tetrabutylammonium bromide was prepared to prepare a solution II. 10g of aluminum hydroxide was added to the solution II with stirring to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 4 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 48 hours at the temperature of 135 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z12-a 2. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-11 type molecular sieve containing framework zirconium.

35g of each of the molecular sieves Z12-a1 and Z12-a2, 30g of alumina, 60ml of 0.5% nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked at 120 ℃ for 4 hours, and then the strips are baked at 500 ℃ for 4 hours to obtain the catalyst A12.

2) 8.5g of tin oxychloride is dissolved in isopropanol, and then added into 1000ml of ethyl orthosilicate to prepare a mixed solution I, and the mixed solution I is stirred for 50 minutes at room temperature. 2700ml of aqueous solution containing 10% tetrapropylammonium hydroxide was prepared to prepare solution II. 30g of alumina sol (40% of alumina content) was added to the solution II with stirring to obtain a feed solution III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 37 hours at the temperature of 170 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z12 b. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-11 eutectic molecular sieve containing framework tin.

70g of the Z12B molecular sieve, 30g of alumina, 1g of magnesium oxide, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst B12.

The results of the analytical tests are shown in Table 1.

[ example 13 ]

1) 6g of zirconium oxychloride is dissolved in isopropanol, and then the solution is added into 1000ml of ethyl orthosilicate to prepare a mixed solution I, and the mixed solution I is stirred for 50 minutes at room temperature. 2700ml of aqueous solution containing 11% tetramethylethylenediamine was prepared to prepare solution II. And adding 50g of aluminum sulfate into the solution II under the stirring state to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃ and then crystallized for 48 hours at the temperature of 180 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z13-a. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-35 eutectic molecular sieve containing framework zirconium.

70g of the Z13-a molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst A13.

2) After 8.5g of tin tetrachloride was dissolved in isopropanol, the resulting solution was added to 700ml of silica sol (containing 40% SiO2) to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of water solution containing 8% of n-butylamine is prepared to prepare solution II. 10g of aluminum hydroxide was added to the solution II with stirring to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 42 hours at the temperature of 165 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z13 b-1. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5 type molecular sieve containing framework tin.

After 8.5g of tin tetrachloride was dissolved in isopropanol, the resulting solution was added to 700ml of silica sol (containing 40% SiO2) to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of an aqueous solution containing 8% tetrabutylammonium bromide was prepared to prepare a solution II. 10g of aluminum hydroxide was added to the solution II with stirring to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 4 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 36 hours at the temperature of 135 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z13 b-2. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-11 type molecular sieve containing framework tin.

35g of each of the molecular sieves Z13B-1 and Z13B-2, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked at 120 ℃ for 4 hours, and then the strips are baked at 500 ℃ for 4 hours to obtain the catalyst B13.

The results of the analytical tests are shown in Table 1.

[ example 14 ]

1) Preparing Zr-ZSM-5 molecular sieve Z12a-1 by the method of [ example 12 ], taking 70g of the Z12a-1 molecular sieve, 30g of alumina, 60ml of 0.5% nitric acid and 5g of sesbania powder, kneading, extruding into strips, baking for 4 hours at 120 ℃, and then baking for 4 hours at 500 ℃ to obtain the catalyst A14.

2) Tin tetrachloride (8.5 g) was dissolved in isopropanol, and then added to ethyl orthosilicate (1000 ml) to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of aqueous solution containing 11% tetramethylethylenediamine was prepared to prepare solution II. And adding 50g of aluminum sulfate into the solution II under the stirring state to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃, and then crystallized for 42 hours at the temperature of 175 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z14-b. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-5/ZSM-35 eutectic molecular sieve containing framework tin.

70g of the Z14-B molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst B14.

The results of the analytical tests are shown in Table 1.

[ example 15 ]

1) Preparing Zr-ZSM-11 molecular sieve Z12a-2 by the method of [ example 12 ], kneading 70g of the molecular sieve, 30g of alumina, 60ml of 0.5% nitric acid and 5g of sesbania powder, extruding into strips, baking at 120 ℃ for 4 hours, and baking at 500 ℃ for 4 hours to obtain catalyst A15.

2) Preparing a Sn-ZSM-5 molecular sieve Z13B-1 by the method of [ example 13 ], kneading 70g of the molecular sieve, 30g of alumina, 60ml of 0.5% nitric acid and 5g of sesbania powder, extruding into strips, baking at 120 ℃ for 4 hours, and baking at 500 ℃ for 4 hours to obtain a catalyst B15.

The results of the analytical tests are shown in Table 1.

[ example 16 ]

1) 6g of zirconium oxychloride was dissolved in isopropanol, and then added to 700ml (containing 40% SiO2) to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of 11% cyclohexylamine-containing aqueous solution is prepared to prepare solution II. And adding 40g of aluminum sulfate into the solution II under the stirring state to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃ and then crystallized for 48 hours at the temperature of 180 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z16-a. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form of the molecular sieve is ZSM-35 molecular sieve containing framework zirconium.

70g of the Z16-a molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst A16.

2) Preparing a Sn-ZSM-11 molecular sieve Z13B-2 by the method of [ example 13 ], kneading 70g of the molecular sieve, 30g of alumina, 60ml of 0.5% nitric acid and 5g of sesbania powder, extruding into strips, baking at 120 ℃ for 4 hours, and baking at 500 ℃ for 4 hours to obtain a catalyst B16.

The results of the analytical tests are shown in Table 1.

[ example 17 ]

1) 6g of zirconium oxychloride was dissolved in isopropanol, and then added to 700ml (containing 40% SiO2) to prepare a mixed solution I, which was stirred at room temperature for 50 minutes. 2700ml of an aqueous solution containing 4% of n-propylamine and 8% of hexamethylenetetramine (R2) was prepared to prepare a solution II. And adding 5g of aluminum sulfate into the solution II under the stirring state to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH value to 4 by using sulfuric acid to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 60 ℃, and then crystallized for 130 hours at the temperature of 180 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z17-a. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form of the molecular sieve is ZSM-39 molecular sieve containing framework zirconium.

70g of the Z17-a molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst A17.

2) After 8.5g of tin tetrachloride was dissolved in isopropanol, 700ml (containing 40% SiO2) was added to prepare a mixed solution I, which was then stirred at room temperature for 50 minutes. 2700ml of 11% cyclohexylamine-containing aqueous solution is prepared to prepare solution II. And adding 40g of aluminum sulfate into the solution II under the stirring state to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH to 6 by using nitric acid and ammonia water to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 45 ℃ and then crystallized for 48 hours at the temperature of 180 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z17-b. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-35 molecular sieve containing framework tin.

70g of the Z17-B molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst B17.

The results of the analytical tests are shown in Table 1.

[ example 18 ]

1) After 8.5g of tin tetrachloride was dissolved in isopropanol, 700ml (containing 40% SiO2) was added to prepare a mixed solution I, which was then stirred at room temperature for 50 minutes. 2700ml of aqueous solution containing 4% of n-propylamine and 8% of hexamethylenetetramine is prepared to prepare solution II. And adding 5g of aluminum sulfate into the solution II under the stirring state to obtain a feed liquid III. Slowly adding the solution I into the feed liquid III under the stirring state, and adjusting the pH value to 4 by using sulfuric acid to obtain feed liquid IV; after being uniformly stirred, the material liquid IV is placed in a crystallization kettle for aging for 20 hours at the temperature of 60 ℃, and then crystallized for 140 hours at the temperature of 180 ℃; and after crystallization, taking out, carrying out vacuum filtration, washing with deionized water, placing in an oven for drying at 120 ℃, and roasting at 550 ℃ for 4 hours to obtain molecular sieve powder Z18-b. The obtained molecular sieve is characterized by XRD and UV-vis, and the crystal form is ZSM-39 molecular sieve containing framework tin.

70g of the Z18-B molecular sieve, 30g of alumina, 60ml of 0.5 percent nitric acid and 5g of sesbania powder are kneaded and extruded into strips, the strips are baked for 4 hours at 120 ℃, and then the strips are baked for 4 hours at 500 ℃ to obtain the catalyst B18.

2) Catalyst a1 was charged to the first reaction zone [ example 1 ].

The results of the analytical tests are shown in Table 1.

[ example 19 ]

Catalyst a17 was charged to the first reaction zone [ example 17 ].

Catalyst B18 was charged to the second reaction zone [ example 18 ].

[ COMPARATIVE EXAMPLE 1 ]

[ example 1 ] catalyst A1 was charged into the first and second reaction zones, respectively. The results of the analytical tests are shown in Table 1.

[ COMPARATIVE EXAMPLE 2 ]

[ example 1 ] catalyst B1 was charged into the first and second reaction zones, respectively. The results of the analytical tests are shown in Table 1.

TABLE 1

[ example 20 ]

Examine [ examples 1-19 ] the application of A/B two catalysts in butene double bond isomerization reaction.

The catalysts of the present invention [ examples 1 to 19 ] were charged into the first and second reaction zones, respectively, in the manner shown in Table 1 to conduct reaction evaluation.

The raw material comprises 12.1% of n-butane, 35.6% of cis-2-butene and 51.3% of trans-2-butene mixed C4. The temperature of the first reaction zone is controlled to be 250 ℃, the reaction pressure is 0.4MPa, and the weight space velocity is 8 hours^-1The temperature of the second reaction zone is 350 ℃, the reaction pressure is 0.4MPa, and the weight space velocity is 8 hours^-1The catalysts were evaluated under the conditions and the reaction results are shown in Table 2.

[ COMPARATIVE EXAMPLE 3 ]

The respective first and second reaction zones were charged in the manner as described in Table 1 of the catalyst to conduct evaluation of the reaction.

TABLE 2

Catalyst loading	2-butene conversion%	1-butene selectivity,%)
			Example 1	22.2	99.5
Example 2	22.3	99.4
			Example 3	22.2	99.3
Example 4	21.9	99.3
			Example 5	21.7	99.2
Example 6	22.3	99
			Example 7	21.8	99.3
Example 8	22.3	99.1
			Example 9	22.3	98.9
Example 10	21.8	99.5
			Example 11	19.8	99.4
Example 12	19.7	99.3
			Example 13	21.9	99.2
Example 14	22.1	99.1
			Example 15	22.3	99
Example 16	22.2	99.1
			Example 17	22.3	99.2
Example 18	22.3	99.1
			Example 19	21.9	99.2
Comparative example 1	22.3	94.54
			Comparative example 2	19.33	98.1

Therefore, the catalyst with different activities is loaded in different areas, so that higher conversion rate and selectivity can be obtained simultaneously, and the comprehensive performance is obviously higher than that of a reference sample.

[ examples 21 to 27 ]

The catalysts a1 and B1 obtained in the present invention [ example 1 ] were subjected to reaction evaluation in the manner of [ example 20 ], and tests were carried out while changing the process conditions, and the reaction conditions and results are shown in table 3.

TABLE 3

[ COMPARATIVE EXAMPLE 4 ]

The first reaction zone is SiO by the method disclosed in the document CN102649671A₂/Al₂O₃ZSM-11 molecular sieve with the mol ratio of 200, and the second reaction zone is silicon oxide.

The raw material comprises 12.1% of n-butane, 35.6% of cis-2-butene and 51.3% of trans-2-butene mixed C4. The temperature of the first reaction zone is controlled to be 320 ℃, the reaction pressure is 0.8MPa, and the weight space velocity is 20 hours^-1The temperature of the second reaction zone is 340 ℃, the reaction pressure is 0.5MPa, and the weight space velocity is 10 hours^-1The catalyst was evaluated under the conditions and the reaction results were: the 2-butene conversion was 23.2% and the 1-butene selectivity was only 97.1%.

Comparative example 4 the catalyst used in the first reaction zone was an unmodified ZSM-11 molecular sieve, which was less acidic and less active than the molecular sieve Zr-ZSM with framework zirconium of the present invention. The degree of conversion of 2-butene in the first reaction zone is higher and the amount of 2-butene participating in the reaction in the second reaction zone is smaller, compared to [ comparative example 4 ], so that the reaction severity in the second reaction zone is lower. Meanwhile, the molecular sieve Sn-ZSM with the framework tin in the second reaction zone not only keeps the activity of the catalyst, but also controls strong active sites, so that the catalyst can keep good 1-butene selectivity at high temperature.

Claims

1. A method for producing 1-butene through 2-butene isomerization comprises the following steps:

2. The method for producing 1-butene through 2-butene isomerization according to claim 1, wherein the catalyst A comprises 30 to 90 parts by weight of Zr-ZSM and 10 to 70 parts by weight of first binder, preferably 40 to 80 parts by weight of Zr-ZSM and 20 to 60 parts by weight of first binder, more preferably 50 to 80 parts by weight of Zr-ZSM and 20 to 50 parts by weight of first binder; relative to the total weight parts of the Zr-ZSM and the first binder.

3. The process for the isomerization of 2-butene to 1-butene according to any one of claims 1 to 2 wherein the Zr-ZSM molecule is selected from the group consisting of Zr-ZSM-5, Zr-ZSM-11, Zr-ZSM-35 and Zr-ZSM-39; preferably a mechanical mixture of at least two selected from the group consisting of Zr-ZSM-5, Zr-ZSM-11, Zr-ZSM-35 and Zr-ZSM-39; more preferably eutectic molecular sieves of at least two selected from the group consisting of Zr-ZSM-5, Zr-ZSM-11, Zr-ZSM-35 and Zr-ZSM-39; most preferred is Zr-ZSM-5/ZSM-11 eutectic molecular sieve.

4. The process for the isomerization of 2-butene to 1-butene according to claim 2 wherein the first binder is at least one member selected from the group consisting of alumina and silica.

5. The method for producing 1-butene through 2-butene isomerization according to any one of claims 1 to 4, wherein the Zr-ZSM molecular sieve has a Si/Zr molar ratio of 50 to 1000, preferably 100 to 500.

6. The method for producing 1-butene through 2-butene isomerization according to claim 1, wherein the catalyst B comprises 50 to 99 parts by weight of Sn-ZSM molecular sieve and 1 to 50 parts by weight of second binder, preferably 55 to 95 parts by weight of Sn-ZSM molecular sieve and 5 to 45 parts by weight of second binder; more preferably, the composite material comprises 60-90 parts of Sn-ZSM molecular sieve and 10-40 parts of second binder; relative to the total weight parts of the Sn-ZSM molecular sieve and the second binder.

7. The process for the isomerization of 2-butene to 1-butene according to claim 1 or 6 wherein the Sn-ZSM molecules are screened for one of the group consisting of Sn-ZSM-5, Sn-ZSM-11, Sn-ZSM-35 and Sn-ZSM-39; preferably a mechanical mixture of at least two selected from the group consisting of Sn-ZSM-5, Sn-ZSM-11, Sn-ZSM-35 and Sn-ZSM-39; more preferably eutectic molecular sieves of at least two selected from the group consisting of Sn-ZSM-5, Sn-ZSM-11, Sn-ZSM-35 and Sn-ZSM-39; most preferred is Sn-ZSM-5/ZSM-11 eutectic molecular sieve.

8. The process for the isomerization of 2-butene to 1-butene according to claim 6 wherein the second binder is at least one selected from the group consisting of alumina and silica.

9. The method for producing 1-butene through 2-butene isomerization according to claims 1 and 6-8, wherein the molar ratio of silicon to tin in the Sn-ZSM molecular sieve is 50-700, preferably 100-500.

10. The process for the isomerization of 2-butene to 1-butene according to claims 1 to 9 wherein neither of said catalyst a nor said catalyst B comprises an alkaline earth metal element or an oxide thereof.

11. The process for the isomerization of 2-butene to 1-butene according to claim 10 wherein the alkaline earth metal element is at least one selected from the group consisting of magnesium, calcium, strontium and barium; in particular magnesium.

12. The method for producing 1-butene through 2-butene isomerization according to claim 1, wherein the reaction temperature of the first reaction zone is 150-280 ℃, the reaction pressure is 0-1 MPa, and the weight space velocity is 1-20 hours^-1(ii) a The preferable reaction temperature is 180-270 ℃, the pressure is 0.5-1 MPa, and the weight space velocity is 2-10 hours^-1。

13. The method for producing 1-butene through 2-butene isomerization according to claim 1, wherein the reaction temperature of the second reaction zone is 280-420 ℃, the pressure is 0-1 MPa, and the weight space velocity is 1-20 hours^-1(ii) a The preferable contact temperature is 320-400 ℃, the pressure is 0.5-1 MPa, and the weight space velocity is 2-10 hours^-1。

14. The process for the isomerization of 2-butene to 1-butene according to claim 1 wherein the reaction temperature of said first reaction zone is lower than the reaction temperature of said second reaction zone.

15. The method for producing 1-butene through 2-butene isomerization according to claim 1, wherein the stream containing 2-butene is derived from a refinery catalytic cracking unit, an ethylene plant steam cracking unit or a coal-to-olefins unit by-product mixed C-IV stream, preferably a C-IV stream obtained by removing 1, 3-butadiene and isobutene from a refinery catalytic cracking unit, an ethylene plant steam cracking unit or a coal-to-olefins unit by-product mixed C-IV stream.

16. Process for the isomerization of 2-butene to 1-butene according to claim 1 wherein said 2-butene containing stream is a mixture of 1-butene and 2-butene not in accordance with thermodynamic equilibrium values.

17. The process for the isomerization of 2-butene to 1-butene according to claim 1 wherein the 2-butene containing stream has a mass concentration of 1-butene lower than 4% and a mass concentration of 2-butene higher than 45%.

18. The process for the isomerization of 2-butene to 1-butene according to claim 1 wherein the mass concentration of 1, 3-butadiene in said 2-butene containing stream is less than 30 ppm.

19. The method for producing 1-butene through 2-butene isomerization according to claim 1, wherein the weight ratio of the catalyst A to the catalyst B is 0.1-8: 1, preferably 0.2-5: 1, and more preferably 0.5-4: 1.