CN101244973B - Method for removing alkyne in high purity isoprene - Google Patents
Method for removing alkyne in high purity isoprene Download PDFInfo
- Publication number
- CN101244973B CN101244973B CN200710063958A CN200710063958A CN101244973B CN 101244973 B CN101244973 B CN 101244973B CN 200710063958 A CN200710063958 A CN 200710063958A CN 200710063958 A CN200710063958 A CN 200710063958A CN 101244973 B CN101244973 B CN 101244973B
- Authority
- CN
- China
- Prior art keywords
- isoprene
- alkynes
- high purity
- entrainer
- alkyne
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a method for removing alkyne in isoprene with high purity, belonging to technical field of alkyne removal; aiming at solving the existing problems of a second extraction unit in carbonium 5 separation process, such as high energy consumption, complex operation, harsh operation demand and big extraction solvent loss, etc., the invention provides a method for using entrainer which can form azeotrope with alkyne and can not form azeotrope with isoprene to remove alkyne by azeotropic distillation; the alkyne is separated by the isoprene and the entrainer through an azeotropic distillation tower; the entrainer with the alkyne which can be used repeatedly removes alkyne hydrogenation by the hydrogenation reactor, and then is separated by a gas-liquid separation tank. The method for removing the alkyne in the isoprene with high purity has the advantages of few types of equipment, simple operation and easy operation; the heat and energy consumption is about 20 percent of the heat and energy consumption of the existing second extraction unit under the same treatment load, thus reducing the production and construction cost largely. .
Description
Technical field
The present invention relates to a kind of method that removes alkynes, more particularly, the present invention relates to a kind of method that removes alkynes in the high purity isoprene.
Background technology
Diolefins such as isoprene, cyclopentadiene and m-pentadiene are rich in a considerable amount of C5 fractions of by-product in the C5 fraction in the process of petroleum cracking system ethene.These diolefin chemical property are active, are important chemical material.Because petroleum hydrocarbon cracking raw materials, cracking severity and separation degree is different, diolefin content is different in the cracked C 5 fraction, and total content is between 40～60%.Therefore, separate and utilize C5 fraction to improving the economic benefit of ethylene unit, the comprehensive utilization petroleum resources have far reaching significance.
Cracked C 5 fraction contain more than 20 kind of boiling point close, easily form the component of azeotrope each other, from wherein isolating the higher C 5 diene of comprehensive utilization value, technology is comparatively complicated.C5 fraction contains for example alkynes such as crotonylene and valylene, these alkynes content are generally in 0.1～2% scope, because their chemical property is active, be the main detrimental impurity of reaction of C 5 diene product and polymerization process, therefore the alkynes that removes effectively wherein is the important step of cracked C 5 fraction separating technology.
In order to produce highly purified isoprene product, generally adopt the two-section extraction rectificating method in the prior art, the existing employed extraction solvent of industrialized cracked C 5 fraction separation method has dimethyl formamide (DMF), acetonitrile etc.For example in carbon five separation process of Beijing Chemical Research Institute's exploitation, first extraction cells removes alkane and the monoolefine in the cracked C 5 fraction, make chemical grade isoprene, second extraction cells removes alkynes and cyclopentadiene wherein, alkynes mainly is crotonylene and valylene, but second extraction cells exists problems, (1) in such two-section extraction rectificating method, operating equipment is more, the energy consumption of second extraction cells is very high, needs strict operation, and the simmer down to operation in some equipment of (2) alkynes brings unsafe factor, there is black bits latch up phenomenon in (3) second extraction cells, solvent recovery unit has a large amount of burnt matter, and is difficult to cleaning, and (4) solvent-oil ratio is big, increase production cost, had problem of environmental pollution simultaneously.
Therefore the low technology of energy consumption of studying a kind of simple possible replaces the method that removes alkynes in second extraction cells, will be the huge advance made of cracked C 5 fraction separation method.
Summary of the invention
The present invention is directed to existing second extraction cells and remove the problem that alkynes exists, a kind of method that adopts the azeotropic distillation method to remove alkynes is proposed, do not need second extraction cells, utilize a kind of energy and alkynes, especially the valylene entrainer that forms azeotrope is isolated alkynes, makes alkynes in the high purity isoprene product reach the requirement of polymerization-grade.
Concrete technical scheme is as follows.
The method that removes alkynes in the high purity isoprene that the present invention proposes may further comprise the steps:
(1) azeotropic distillation: use can form azeotrope with alkynes in the isoprene and not form the entrainer of azeotrope with isoprene, entrainer and high purity isoprene enter azeotropy rectification column, isolate entrainer and alkynes from cat head, from tower still or tower still side line extraction isoprene;
(2) hydrogenation: hydrogen with enter the catalytic hydrogenation reaction device from the material that contains alkynes and entrainer of azeotropic distillation column overhead, through shortening with the alkynes hydrogenation and removing;
(3) gas-liquid separation: the material from the catalytic hydrogenation reaction device enters knockout drum, and the effusive liquid in lower end is delivered to azeotropy rectification column and recycled, and the compressed catalytic hydrogenation reaction device of delivering to of the gas that the upper end emits reuses.
Described entrainer is preferably iso-pentane.The boiling point of isoprene and valylene (valylene) is 34 ℃, adopts the conventional distillation method not separate between them.Yet iso-pentane can form azeotrope with crotonylene and valylene respectively, does not form azeotrope with isoprene, and the boiling point of the azeotrope that iso-pentane and valylene form is 26.3 ℃, and azeotropic consists of the iso-pentane of 63.8 quality %.The boiling point of the azeotrope that iso-pentane and crotonylene form is lower.
Described high purity isoprene is that cracked C 5 fraction is through taking off light and/or taking off the isoprene concentrated solution that heavily removes m-pentadiene and cyclopentadiene and obtain, isoprene or the chemical grade isoprene that cracked C 5 fraction obtains through extracting rectifying.The isoprene concentrated solution can be, cyclopentadiene dimerization light through taking off and take off the isoprene concentrated solution that heavy process obtains, such as concentrate the situation of separating isoprene again through this processing, also can be the isoprene concentrated solution that contains Skellysolve A that adopts Skellysolve A to obtain for entrainer rectifying, this concentrated solution can be used for polyreaction through removing alkynes.Cracking c_5 process extracting rectifying process can be removed alkane and monoolefine wherein, before extracting rectifying, can remove m-pentadiene in advance, also can not remove m-pentadiene, but remove cyclopentadiene generally speaking in advance, the situation that does not remove m-pentadiene can be isolated m-pentadiene, or the chemical grade isoprene that obtains of extracting rectifying, these isoprene adopt method of the present invention can remove alkynes.
There is no particular limitation to the number of theoretical plate of azeotropy rectification column and concrete operations condition, and those skilled in the art can utilize above-mentioned separation principle to select suitable number of theoretical plate and operational condition according to practical situation.Under the certain situation of number of theoretical plate, charging mass flux ratio that can be by changing iso-pentane and isoprene and reflux ratio are to remove the alkynes in the isoprene effectively, when the charging mass flux ratio of iso-pentane and isoprene increases, can reduce reflux ratio, in the charging mass flux ratio of iso-pentane and isoprene hour, can increase backflow and recently achieve the goal.Also can change number of theoretical plate, can remove alkynes effectively by changing number of theoretical plate and operational condition equally.By calculating design variable and the operational condition that those skilled in the art can easily obtain azeotropy rectification column.Example as an illustration, preferred described azeotropy rectification column has 70～200 theoretical stages, and from tower middle part charging, the weight ratio of high purity isoprene and entrainer is 20: 0.5～5, and reflux ratio is 50～120.
Palladium-based catalyst or nickel-base catalyst are housed in the catalytic hydrogenation reaction device.Because the material from the azeotropic distillation cat head contains a large amount of iso-pentane and a spot of alkynes and isoprene, the purpose of carrying out shortening in this hydrogenator is exactly the alkynes hydrogenation and removing with wherein, this hydrogenation reaction can be that alkynes is removed in selective hydrogenation, also can be that complete hydrogenation reaction is removed the hydrogenation of unsaturated hydrocarbons that comprises isoprene and removed, therefore can use industrial normally used hydrogenation with palladium-based catalyst or nickel-base catalyst, for example the various hydrogenation catalysts produced of China Petrochemical Industry Beijing Chemical Research Institute.There is no particular limitation to hydrogenation conditions, those skilled in the art can freely select according to general knowledge, as long as remove the crotonylene in the iso-pentane, valylene hydrogenation just passable, the crotonylene hydrogenation becomes butane, its boiling point is very low, can emit by emptying on the return tank of azeotropy rectification column when iso-pentane recycles, valylene and isoprene are hydrogenated into iso-pentane, do not need to separate again.The monoolefine that generates of the isoprene of hydrogenation and partial hydrogenation does not loop back azeotropy rectification column with iso-pentane, and the yield of isoprene is improved, and it is very little that a spot of alkene turns back in the azeotropy rectification column quality product influence to isoprene, can ignore.
Highly purified isoprene is when being used for polyreaction, a spot of alkynes can consume polymerizing catalyst in large quantities, and bring disadvantageous color to polymerisate, therefore general requirement be used for the polymeric high purity isoprene alkynes less than 50ppm, use method of the present invention can remove wherein alkynes easily.
In the present invention, concentration all in mass, per-cent is meant mass percent, ppm is meant * 10
-6(mass concentration).
Method of the present invention is compared with existing second extraction cells, has the following advantages:
1. the equipment that treatment process of the present invention is used is few, simple to operate, easy handling, and construction cost and production cost reduce.
2. under same treatment load, the heat energy consumption of treatment process of the present invention be about existing second extraction cells the heat energy consumption 20%, thereby can reduce production costs widely.
Description of drawings
Fig. 1 is the synoptic diagram of the existing cracked C 5 fraction separation process of China.
Fig. 2 is the schematic flow sheet that removes the method for alkynes in the high purity isoprene of the present invention.
Nomenclature:
In Fig. 1, the pre-lightness-removing column of T-101; The R-101 dipolymer reactor; The pre-weight-removing column of T-102; T-201 first extraction tower; T-202, T-203 one collection Analytic Tower; The T-204 weight-removing column; T-301 second extraction tower; The T-302 lightness-removing column; T-303 two collection Analytic Towers; T-304 vacuum analysis tower; T-401 carbon five steams tower; T-402 m-pentadiene treating tower; T-403 dicyclopentadiene treating tower; The E-501 solvent regeneration tower; The burnt matter dilution of V-501 tower; T-501 solvent treatment tower;
In Fig. 2,1 azeotropy rectification column; 2 hydrogenators; 3 knockout drums.
Embodiment
Below in conjunction with the further method that removes alkynes in the high purity isoprene of the present invention of accompanying drawing.
With reference to Fig. 1, C5 fraction separation method by Beijing Chemical Research Institute's research has the commerical test device in Kingsoft construction, adopt the two-section extraction rectificating method, comprise 5 unit altogether, i.e. raw materials pretreatment unit, first extraction cells, second extraction cells, m-pentadiene and dicyclo refined unit and solvent recovery unit.The raw materials pretreatment unit removes most of alkynes and light constituent in pre-lightness-removing column T-101, through dipolymer reactor R-101 cyclopentadiene is transformed into dicyclopentadiene, removes in pre-weight-removing column T-102.In first extraction cells, the first extraction tower T-201 adopts solvent removal alkane and monoolefine, the solvent that contains isoprene is resolved the recovery solvent through a collection Analytic Tower T-202 and T-203, the material that parses contains components such as isoprene, alkynes (being mainly crotonylene, valylene), m-pentadiene, a small amount of cyclopentadiene, cyclopentenes, pentamethylene, isolates isoprene, alkynes, micro-cyclopentadiene through weight-removing column T-204 from cat head.In second extraction cells, utilize solvent in the second extraction tower T-301, valylene and cyclopentadiene to be extracted in the solvent once more, cat head is isolated isoprene and crotonylene, this material enters lightness-removing column T-302 general crotonylene (isoprene: 34 ℃ wherein, crotonylene: 27 ℃) isolate, solvent reclaims solvent through normal pressure Analytic Tower T-303 and decompression Analytic Tower T-304.M-pentadiene and dicyclo refined unit obtain m-pentadiene product and dicyclo product through decarburization five tower T-401, m-pentadiene treating tower T-402 and dicyclo treating tower T-403.Solvent recovery unit at first utilizes regeneration still E-501 to remove wherein burnt matter, burnt matter is emitted through dilution in V-501, utilize water and dicyclo azeotropic to steam wherein dicyclo at solvent treatment tower T-501 then, the cyclopentadiene that the recovery solvent of avoiding entering second extraction cells has in the isoprene product that the dicyclo component makes production is defective.
Explain method of the present invention below with reference to Fig. 2.
As shown in Figure 2, high purity isoprene and entrainer iso-pentane enter from the middle part of azeotropy rectification column 1, iso-pentane and crotonylene in tower, valylene forms azeotrope, isolate iso-pentane and alkynes from cat head, from tower still or tower still side line extraction isoprene product, the material that comes out from cat head enters hydrogenator 2, remove wherein alkynes through the catalytic hydrogenation reaction of catalyzer, through knockout drum 3 tail gas and liquid separation are opened then, liquid mainly contains the butane of iso-pentane and trace, recycle as entrainer, tail gas enters the hydrogenator hydrogenation again through compressor compresses.
Embodiment 1
Adopt method of the present invention to remove alkynes in the chemical grade isoprene, contain the crotonylene of 400ppm and the valylene of 400ppm in the chemical grade isoprene.
The chemical grade isoprene of 1000kg/h and the iso-pentane of 50kg/h enter from the azeotropy rectification column middle part respectively, the number of theoretical plate of azeotropy rectification column is 100, charging on the 40th block of plate, reflux ratio is 100, the cat head produced quantity is 70kg/h, tower still produced quantity 980kg/h, by analysis, the alkynes total content is 35ppm in the tower still extraction material.This isoprene can be used for polyreaction.
The material of cat head extraction enters in the catalytic hydrogenation reaction device of the nickel-base catalyst that Beijing Chemical Research Institute's production is housed, and hydrogenation pressure is 3.0Mpa, and hydrogenation temperature is 45～60 ℃, and the volume hourly space velocity is 3h
-1, by analysis, the material behind the hydrogenation does not contain alkynes and alkene substantially, enters knockout drum then and carries out gas-liquid separation, and liquid recycles as entrainer, and the compressed hydrogenator that enters again of tail gas uses.
Embodiment 1
Adopt method of the present invention to remove alkynes in the isoprene concentrated solution, the table composed as follows of this isoprene concentrated solution.
| Component | Content (quality %) | Component | Content (quality %) |
| Skellysolve A | 6.90 | Isoprene | 62.40 |
| The 1-amylene | 4.70 | 2-butyne | 0.0003 |
| 2-methyl-1-butene alkene | 5.00 | Instead-1,3-pentadiene | 0.10 |
| Instead-the 2-amylene | 8.10 | Cyclopentadiene | 0.96 |
| Suitable-the 2-amylene | 6.40 | Valylene | 0.0090 |
| The 2-methyl-2-butene | 3.36 |
The isoprene concentrated solution of 1000kg/h and the iso-pentane of 80kg/h enter from the azeotropy rectification column middle part respectively, the number of theoretical plate of azeotropy rectification column is 110, charging on the 55th block of plate, reflux ratio is 100, the cat head produced quantity is 100kg/h, tower still produced quantity 980kg/h, by analysis, the alkynes total content is 20ppm in the tower still extraction material.This isoprene concentrated solution can be used for polyreaction.
The material of cat head extraction enters in the catalytic hydrogenation reaction device of the nickel-base catalyst that Beijing Chemical Research Institute's production is housed, and hydrogenation pressure is 3.0Mpa, and hydrogenation temperature is 45～60 ℃, and the volume hourly space velocity is 3h
-1, by analysis, the material behind the hydrogenation does not contain alkynes and alkene substantially, enters knockout drum then and carries out gas-liquid separation, and liquid recycles as entrainer, and the compressed hydrogenator that enters again of tail gas uses.
Claims (3)
1. a method that removes alkynes in the high purity isoprene is characterized in that, said method comprising the steps of:
(1) azeotropic distillation: use iso-pentane as entrainer, entrainer and high purity isoprene enter azeotropy rectification column, isolate entrainer and alkynes from cat head, from tower still or tower still side line extraction isoprene;
(2) hydrogenation: hydrogen with enter the catalytic hydrogenation reaction device from the material that contains alkynes and entrainer of azeotropic distillation column overhead, through shortening with the alkynes hydrogenation and removing;
(3) gas-liquid separation: the material from the catalytic hydrogenation reaction device enters knockout drum, and the effusive liquid in lower end is delivered to azeotropy rectification column and recycled, and the compressed hydrogenator of delivering to of the gas that the upper end emits reuses;
Described high purity isoprene is cracked C 5 fraction remove m-pentadiene and the cyclopentadiene isoprene concentrated solution that obtains, isoprene or the chemical grade isoprene that cracked C 5 fraction obtains through extracting rectifying.
2. the method that removes alkynes in the high purity isoprene as claimed in claim 1, it is characterized in that described azeotropy rectification column has 70～200 theoretical stages, from tower middle part charging, the weight ratio of high purity isoprene and entrainer is 20: 0.5～5, and reflux ratio is 50～120.
3. the method that removes alkynes in the high purity isoprene as claimed in claim 1 is characterized in that, palladium-based catalyst or nickel-base catalyst are housed in the catalyst hydrogenation reactor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200710063958A CN101244973B (en) | 2007-02-15 | 2007-02-15 | Method for removing alkyne in high purity isoprene |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200710063958A CN101244973B (en) | 2007-02-15 | 2007-02-15 | Method for removing alkyne in high purity isoprene |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101244973A CN101244973A (en) | 2008-08-20 |
| CN101244973B true CN101244973B (en) | 2010-05-19 |
Family
ID=39945693
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200710063958A Active CN101244973B (en) | 2007-02-15 | 2007-02-15 | Method for removing alkyne in high purity isoprene |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101244973B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103086833B (en) * | 2011-11-02 | 2015-03-11 | 中国石油化工股份有限公司 | Method for separating C5 fraction |
| CN103086822B (en) * | 2011-11-02 | 2016-03-30 | 中国石油化工股份有限公司 | A kind of separation method of m-pentadiene |
| AR101431A1 (en) * | 2013-06-05 | 2016-12-21 | Gtc Technology Us Llc | PROCESS AND APPARATUS TO SEPARATE DI-OLEFINS C₅ FROM PIRÓISIS NAFTAS |
| CN105481627B (en) * | 2015-11-23 | 2018-07-27 | 山东粤安新型材料有限公司 | A kind of high-purity propane production method for environmental protection refrigerant R290 |
| CN109721453A (en) * | 2017-10-27 | 2019-05-07 | 中国石油化工股份有限公司 | A kind of method of separating high-purity pentadiene |
| CN114276834B (en) * | 2021-12-24 | 2023-03-14 | 宁波甬华树脂有限公司 | Preparation method of refined C5 fraction |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1412165A (en) * | 2001-10-12 | 2003-04-23 | 中国石油化工股份有限公司 | Separation method of cracked C5 fraction |
| CN1490286A (en) * | 2002-10-16 | 2004-04-21 | 中国石油化工股份有限公司 | Separating method for cracking C5-fraction |
-
2007
- 2007-02-15 CN CN200710063958A patent/CN101244973B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1412165A (en) * | 2001-10-12 | 2003-04-23 | 中国石油化工股份有限公司 | Separation method of cracked C5 fraction |
| CN1490286A (en) * | 2002-10-16 | 2004-04-21 | 中国石油化工股份有限公司 | Separating method for cracking C5-fraction |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101244973A (en) | 2008-08-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101244974B (en) | Method for one-section abstraction distillation separation cracking carbon 5-cut fraction | |
| CN109912380B (en) | Pyrolysis gas separation method and device | |
| CN101450885B (en) | Method for separating carbon 5 fraction by one-stage extraction and rectification | |
| CN101244973B (en) | Method for removing alkyne in high purity isoprene | |
| CN100593530C (en) | Separation method of diene hydrocarbon in five fractions of petroleum cracked carbon | |
| CN1162380C (en) | Separation method of cracked C5 fraction | |
| CN101244976B (en) | Method for producing polymerization level isoprene | |
| CN105585411A (en) | Hydrogenation method of butadiene extraction tail gas | |
| CN103289740A (en) | Method for preparing clean fuel oil from coal tar | |
| CN101244975B (en) | Method for producing polymerization level isoprene with one-section abstraction combined azeotropy distillation | |
| CN101302135B (en) | Method for separating isoprene by front-end hydrogenation one-stage extraction | |
| CN101302134B (en) | Method for separating cracked carbon-5 fraction by front-end alkyne removal one-stage extraction | |
| CN101104573B (en) | Method for separating isoprene by combined rectification | |
| CN101508621A (en) | Method for separating and cracking diene in C5 fraction | |
| CN103205275A (en) | Method for preparing phenol compound and clean fuel oil from coal tar | |
| CN101450909B (en) | Segregation and fractionation regeneration method of dimethylformamide as extracting solvent for cracking carbon 5 | |
| CN115611698B (en) | Process for extracting and separating isoprene by DMF (dimethyl formamide) method | |
| CN102485708B (en) | C5 fraction separation method employing hypergravity extractive distillation apparatus | |
| CN101450908B (en) | Fractional condensation and regeneration method of dimethylformamide as extracting solvent for cracking carbon 5 | |
| CN106187659B (en) | A kind of cracking C6+Increase production the combined technical method of low-carbon aromatic hydrocarbons and low-carbon alkene | |
| CN101397261B (en) | Regeneration method of dimethylformamide as extracting solvent for cracking carbon 5 and use thereof | |
| CN101100412A (en) | Postheating dimerization method for separating C5 diene | |
| CN105087047A (en) | Heavy oil catalytic cracking process for producing heavy and light arene products in productive mode | |
| US9738575B2 (en) | Apparatus for producing ethylene and a producing method thereof | |
| CN101397232B (en) | Method for separating cracked carbon 5 fraction by using one section extraction of reaction rectification |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |