CN111909718A

CN111909718A - Process and apparatus for olefin polymerization

Info

Publication number: CN111909718A
Application number: CN201910374641.6A
Authority: CN
Inventors: 温朗友; 宗保宁; 郜亮; 夏玥穜; 张伟; 赵志海; 丁晖殿; 俞芳; 杜泽学; 董明会; 喻惠利
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2019-05-07
Filing date: 2019-05-07
Publication date: 2020-11-10
Anticipated expiration: 2039-05-07
Also published as: CN111909718B

Abstract

The invention relates to an olefin polymerization method, which comprises a first reaction zone and a second reaction zone, wherein a polymerization raw material and water enter the first reaction zone and react under the condition of olefin hydration; the output of the first reaction zone is fed into the second reaction zone separately or together with the polymerization raw material, and reacted under the condition of olefin polymerization. The invention effectively reduces the softening condition of the solid phosphoric acid catalyst by arranging two reaction zones.

Description

Process and apparatus for olefin polymerization

Technical Field

The present invention relates to a method and apparatus for olefin polymerization, and more particularly to a method and apparatus for olefin polymerization using a solid phosphoric acid catalyst.

Background

The term "oligomerization" refers to the process of reacting two or more low molecular olefins to form larger molecular olefins. The laminated olefin generated by the laminated reaction can be used as a gasoline component and also as a raw material for producing various fine chemical products, and has wide application. For example, isooctene produced by butene polymerization is a high-quality high-octane gasoline component, and is also a raw material for producing octylphenol, octylamine and the like. Particularly, after the country in 2020 comprehensively enforces the ethanol gasoline policy, butene superposition as a substitute technology of MTBE can be comprehensively popularized and applied.

The olefin polymerization reaction can adopt strong acid resin, solid phosphoric acid, amorphous silica-alumina, molecular sieve, supported sulfate, heteropoly acid, solid super acid and the like as catalysts. Commercially, full component polymerizations of butenes typically employ a solid phosphoric acid catalyst.

The solid phosphoric acid catalyst is a supported catalyst prepared by loading phosphoric acid on a silicon-based carrier (such as silica gel, diatomite, organic diatomite, kaolin, montmorillonite and the like), and the chemical composition of the supported catalyst mainly comprises free phosphoric acid, silicon phosphate, silicon pyrophosphate and poly-silicon phosphate. The important factor determining the catalytic performance of solid phosphoric acid is the content of free phosphoric acid, and the newly processed solid phosphoric acid catalyst generally contains 16-20 m% of free phosphoric acid. Since the solid phosphoric acid catalyst inevitably has free phosphoric acid loss during the use process and the free phosphoric acid loses water and becomes polyphosphoric acid to lose activity, the activator needs to be continuously supplemented during the use process to maintain the catalyst activity. Water is a satisfactory activator, but is also a factor in softening the solid phosphoric acid catalyst. Therefore, the control of the water adding amount is very important, the prior art carries out more researches on the control, and a plurality of methods for controlling the water adding amount are disclosed, but the control means of the methods are complicated, and the effect is still not very ideal.

CN1125827C proposes a method for controlling activity of solid phosphoric acid catalyst in reaction process, which adjusts water inflow of the reactor by detecting acidity of the output product of the polymerization reactor, so as to realize dynamic control of catalyst activity.

CN102361839A proposes a process for producing an olefin dimer, which comprises introducing an olefin-containing raw material containing 10 PPM or more by mass of water and less than the saturated water content at the reaction temperature into a reactor, and carrying out a dimerization reaction of an olefin in the presence of a solid phosphoric acid catalyst.

CN105669340A proposes a method for controlling the oligomerization reaction of low-carbon olefin, which comprises contacting the raw material of superimposed hydrocarbon with sodium dihydrogen phosphate solution in countercurrent, removing harmful impurities, and making the raw material contain 200-3000 PPM water (W ═ a + b. EXP (0.0023t +0.00019 t)²) Controlling, wherein t is the reaction temperature, a is the minimum water content of the reaction, and is a constant related to the olefin type; b is a parameter related to space velocity.

In addition to using water as an activator, the prior art also proposes a method using an alcohol as an activator to activate a solid phosphoric acid catalyst by decomposing the produced water by the alcohol under the action of the solid phosphoric acid catalyst. Compared with water addition, the addition of alcohol in the raw materials for lamination is more convenient, but the consumption of alcohol is large, the price is high, and the raw material cost of the process is increased. In addition, the decomposition of the alcohol simultaneously produces olefins which also participate in the polymerization reaction, and there is a limit to the choice of the alcohol in view of the influence on the properties of the product to be polymerized.

USP4334118 proposes a solid phosphoric acid catalyzed olefin polymerization process using alcohol as an activator for the catalyst instead of water. This application discloses the incorporation of 6.85 mg of isopropanol per gram of propylene and the results of the test show that the solid phosphoric acid catalyst is softened.

US6111159 proposes a hydrocarbon metathesis process in which a solid phosphoric acid catalyst is first started with an anhydrous hydrocarbon mixture and then switched to an alcohol-containing feedstock for the normal metathesis reaction.

The olefin polymerization reaction has the problem of selectivity of product distribution. For example, the mixed carbon four by-produced in the processes of catalytic cracking (FCC), catalytic cracking (DCC), steam cracking, etc. contains a plurality of butene isomers, many reactions can occur between the isomers, and the reaction products do not have high octane numbers, so that the selectivity problem of high octane number products is also faced no matter the selective superposition of butene or the non-selective superposition of butene. For example, in the process of C.sub.C.sub.four polymerization, in addition to the dimerization reaction between isobutylene, codimerization between isobutylene and butene-1 and butene-2, dimerization of butene-2 and butene-1 and codimerization between the two occur, the dimerization product further reacts with C4 olefin to form trimer (C12), tetramer (C16), isomerization reaction between isomers of the polymerization product, and the like. The octane number of the 2,3, 3-trimethylpentene (108 ℃), 2,3, 4-trimethylpentene (boiling point 108 ℃), 3,4, 4-trimethylpentene (boiling point 112 ℃), 2,4, 4-trimethylpentene-1 (boiling point 101 ℃) and 2,4, 4-trimethylpentene-2 (boiling point 105 ℃) in the mixed C.sub.D. product is high; dimethylhexene and methylheptene, which have low octane numbers, in particular trans, 2, 2-dimethylhexene-3 (100.9 ℃), cis-trans 5, 5-dimethylhexene-2 (104 ℃), are almost the same as or between the boiling points of the high octane isomers, and cannot be separated by distillation. In addition, the trimer (C12) in the superimposed product has a higher boiling point, but can still be added into gasoline; whereas the tetramer (C16) has a boiling point above the gasoline boiling range, its addition to gasoline needs to be severely limited or will affect the dry point of the gasoline. Therefore, the dry point of the product is also strictly controlled in the lamination process for the purpose of producing the gasoline component.

In the prior art, when a solid phosphoric acid catalyst is adopted in the superposition reaction, the requirement on the impurity content of raw materials is high, the refining process of the raw materials is complex, and for example, the four-carbon raw material needs to be subjected to demetalization and alkaline nitride treatment to ensure the operation period of the catalyst.

Disclosure of Invention

The object of the present invention is to produce useful products by olefin metathesis, in particular high octane gasoline components by metathesis of propylene and/or butylene.

The first technical problem to be solved by the invention is that olefin polymerization is carried out by taking solid phosphoric acid as a catalyst, and even if a complicated measure for adjusting the dosage of a catalyst activator is not adopted, the softening condition of the solid phosphoric acid catalyst can be effectively relieved, and particularly, the pressure drop rising trend of a solid phosphoric acid catalyst bed layer in a fixed bed reactor is remarkably relieved.

A second technical problem to be solved by the present invention is to improve the control of the dry point of the superimposed product and/or to increase the selectivity of the high octane product during the superimposition process.

The third technical problem to be solved by the present invention is to simplify the strict raw material refining process in the prior art of lamination, and directly use the lamination raw material containing a certain amount of impurities (metal cations and/or basic nitrogen compounds).

The invention provides the following technical scheme.

1. An olefin polymerization method comprises a first reaction zone and a second reaction zone, wherein the first reaction zone is filled with an olefin hydration catalyst, and the second reaction zone is filled with a solid phosphoric acid catalyst; the polymerization raw material and water enter a first reaction zone and react under the condition of olefin hydration; the discharge of the first reaction zone is used as the feed of a second reaction zone independently or together with the polymerization raw material, enters the second reaction zone and reacts under the condition of olefin polymerization; wherein the molar ratio of alcohol to water in the feed to the second reaction zone is 1: 1-20: the alcohol and water together act as an activator for the solid phosphoric acid catalyst in the second reaction zone.

2. The process according to 1, characterized in that the olefin hydration catalyst is selected from one or more of strongly acidic cation exchange resin catalysts, molecular sieve catalysts, heteropolyacid catalysts and acidic ionic liquid catalysts.

3. The method according to 2, characterized in that the strongly acidic cation exchange resin catalyst is one or more selected from the group consisting of sulfonated styrene-divinylbenzene-type resins, sulfonated styrene-divinylbenzene-type resins in which a part of hydrogen atoms on the benzene ring is substituted with chlorine, and perfluorinated sulfonated styrene-divinylbenzene-type resins.

4. Push buttonThe process according to claim 2 or 3, wherein the mass exchange capacity of the strongly acidic cation exchange resin catalyst is 3mmolH⁺/g～5.6mmolH⁺/g。

5. A process according to any one of the preceding claims, characterized in that the total phosphorus content of the solid phosphoric acid catalyst is expressed as P₂O₅Calculated by 50 to 70 percent of the total mass of the catalyst; amount of free phosphoric acid, in H₃PO₄Calculated by 16 to 20 percent of the total mass of the catalyst.

6. A process according to any one of the preceding claims, characterized in that the molar ratio of alcohol to water in the feed to said second reaction zone is 1: 1-10: 1, preferably 1: 1-6: 1, more preferably 1.5: 1-5: 1.

7. the method according to any of the preceding claims, characterized in that the amount of water fed to the first reaction zone is between 0.01% and 5%, preferably between 0.1% and 1%, based on 100% of the total mass of the raw materials for the superposition.

8. A process according to any one of the preceding claims, characterized in that the molar ratio of olefin to water in the feed to the first reaction zone is from 0.5: 1-5: 1.

9. a process according to any one of the preceding claims, characterized in that in the first reaction zone the olefin hydration catalyst is a strongly acidic cation exchange resin catalyst; the reaction temperature is 40-100 ℃; the reaction pressure is 0.5MPa to 10MPa, preferably 4MPa to 8 MPa.

10. The method according to 9, characterized in that the raw material for superposition entering the first reaction zone is 30% -50%, 50% -70%, 70% -90% or 90% -100% by total mass of the raw material for superposition being 100%.

11. The method according to 9 or 10, characterized in that the tertiary olefin content in the raw material for the superposition is 8-10%, 10-15%, 15-25%, 25-35% or 35-45%.

12. The method according to any one of the preceding claims, characterized in that the first reaction zone is operated continuously, the mass space velocity of the feed being 0.2h^－1～10h^－1Preferably 0.2h^－1～5h^－1。

13. The process according to any of the preceding claims, characterized in that the first reaction zone consists of one or more reactors in the form of one or more selected from the group consisting of fixed bed reactors, tank reactors, tubular reactors and tower reactors, preferably fixed bed reactors.

14. The process according to any of the preceding claims, characterized in that in the second reaction zone the reaction temperature is 160 ℃ to 250 ℃, preferably 180 ℃ to 230 ℃; the reaction pressure is 2MPa to 10MPa, preferably 4MPa to 6 MPa.

15. The method according to any of the preceding claims, characterized in that the second reaction zone is constituted by one or more reactors in the form of one or more selected from the group consisting of tank reactors and fixed bed reactors, preferably fixed bed reactors.

16. The method according to any one of the preceding claims, characterized in that the second reaction zone is operated continuously, the mass space velocity of the feed being 0.5h^－1～20h^－1Preferably 0.5h^－1～5h^－1。

17. A process according to any one of the preceding claims, characterized in that a third reaction zone is provided, into which the discharge from the second reaction zone or the superimposed product separated therefrom is passed, and in which the hydrogenation saturation is carried out.

18. The method according to any one of the preceding claims, characterized in that the raw material for the polymerization is a C3-C6 olefin or a mixture of C3-C6 olefin and C3-C6 alkane.

19. The method according to any one of the preceding claims, characterized in that the superimposed feedstock may be a propane dehydrogenation cut, a refinery gas containing propylene and butylene, an isobutane dehydrogenation carbon four cut, a catalytic cracking carbon four cut, a steam cracking carbon four cut, a catalytic cracking light gasoline or a steam cracking light gasoline.

20. A method according to any of the preceding claims, characterized in that the raw lamination stock has a metal content of 1-10 μ g/g (preferably 2-6 μ g/g) and/or a basic nitrogen compound content of 1-10 μ g/g (preferably 2-6 μ g/g).

21. The device for olefin polymerization is characterized by comprising a first reaction zone, a second reaction zone and a polymerization raw material pipeline, wherein the first reaction zone is provided with an activating agent inlet, a reaction raw material inlet and a reaction product outlet, and the second reaction zone is provided with a reaction raw material inlet and a reaction product outlet; the reaction raw material inlet of the first reaction zone and the reaction raw material inlet of the second reaction zone are both connected with a superposed raw material pipeline; the reaction product outlet of the first reaction zone is connected with the reaction raw material inlet of the second reaction zone.

In the prior art, when the solid phosphoric acid catalyst is used for olefin polymerization, a catalyst activator is required to be added. The catalyst activator also serves to soften the catalyst while regulating the catalytic activity. Generally, when a solid phosphoric acid catalyst is used, the reaction temperature is relatively high, for example, for the polymerization of propylene, butene and pentene, the reaction temperature is generally above the critical temperature of the raw materials. Therefore, it is generally considered that the catalyst activator is uniformly mixed with the reaction raw material, and the main factor causing the softening of the catalyst is the amount of the catalyst activator. For this reason, various complicated technical measures are adopted in the art to dynamically adjust the amount of the catalyst activator in accordance with the conditions of the catalyst and the reaction system, but the adjustment effect is not yet ideal. The inventors have found in experiments that the amount of catalyst activator used is not the only important factor in causing softening of the catalyst. If part of olefin in the polymerization raw material reacts with part of catalyst activator water at low temperature to generate alcohol, and then olefin polymerization reaction is carried out, the softening condition of the solid phosphoric acid catalyst can be effectively relieved, and particularly the pressure drop rising trend of a solid phosphoric acid catalyst bed layer in a fixed bed reactor is remarkably relieved. Thus, the present invention has been completed.

Compared with the prior art, the invention has the following characteristics and beneficial technical effects.

In the prior art, when olefin polymerization is carried out by using a solid phosphoric acid catalyst, only the polymerization reaction of the olefin is generally carried out, and other reaction steps are not carried out. Different from the prior art, the invention is provided with two reaction zones, and the hydration reaction of olefin is carried out in the first reaction zone; in the second reaction zone, the polymerization reaction of olefin is carried out by taking solid phosphoric acid as a catalyst.

Compared with the prior art, the invention improves the softening condition of the solid phosphoric acid catalyst by arranging two reaction zones on the premise of ensuring or improving the catalytic activity and selectivity of the solid phosphoric acid catalyst, and particularly remarkably slows down the pressure drop rising trend of a solid phosphoric acid catalyst bed layer in a fixed bed reactor. In addition, on the one hand, the invention does not need to completely react water in the first reaction zone, but controls the water conversion rate within a certain range, and experiments find that the water conversion rate required by the invention is easy to achieve; on the other hand, the process of the present invention is less costly than the commercially available alcohols, does not adversely affect the properties of the laminate, and in some cases also increases the selectivity of the laminate. The present inventors consider that at least the following factors are relevant to the aforementioned technical effect, one of which is that, in the first reaction zone, part of the olefins in the polymerization feed are converted into alcohols; secondly, in the first reaction zone, the conversion rate of water is controlled within a certain range; thirdly, the catalyst activator and the raw materials are uniformly mixed at a molecular level through the reaction process in the first reaction zone. The foregoing is included to assist in understanding the invention, but the invention is not limited by these principles.

Compared with the prior art, when the content of the tertiary olefin in the polymerization raw material is high, particularly the content of isobutene or isoamylene is high, the dry point of the polymerization product can be reduced by adopting the method, the selectivity of the polymerization product is improved, and particularly the selectivity of butene on a high-octane product during polymerization is improved.

Compared with the prior art, when the first reaction zone is filled with the strong acid resin catalyst, the requirement on the impurity content of the laminated raw material is reduced, so that the method is suitable for wider raw materials, and the complicated refining process of the laminated raw material can be simplified or eliminated.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

FIG. 1 is a schematic flow diagram of the process of the present invention.

Detailed Description

The present invention will be described in detail with reference to the following embodiments, but it should be understood that the scope of the present invention is not limited by these embodiments and the principle of the present invention, but is defined by the claims.

In the present invention, anything or matters not mentioned is directly applicable to those known in the art without any change except those explicitly described. Moreover, any embodiment described herein may be freely combined with one or more other embodiments described herein, and the technical solutions or ideas thus formed are considered part of the original disclosure or original description of the present invention, and should not be considered as new matters not disclosed or contemplated herein, unless a person skilled in the art would consider such combination to be clearly unreasonable.

All of the features disclosed in this application can be combined in any combination which is understood to be disclosed or described in this application and which, unless clearly considered to be too irrational by a person skilled in the art, is to be considered as being specifically disclosed and described in this application. The numerical points disclosed in the present specification include not only the numerical points specifically disclosed in the examples but also the endpoints of each numerical range in the specification, and ranges in which any combination of the numerical points is disclosed or recited should be considered as ranges of the present invention.

Technical and scientific terms used herein are to be defined only in accordance with their definitions, and are to be understood as having ordinary meanings in the art without any definitions.

In the present invention, the hydration of olefin means that olefin reacts directly with water to form alcohol.

In the present invention, the tertiary olefin is an olefin having a tertiary carbon atom among double-bonded carbon atoms.

In the present invention, the mass space velocity means the mass of the reaction raw material passing per unit mass of the catalyst per unit time.

In the present invention, C8-TMP represents trimethylpentene.

In the present invention, C8-DMH represents dimethylhexene.

In the present invention, C12-TIB represents trimeric isobutene.

In the present invention, C16-TEB represents tetrapolyisobutene.

In the present invention, TBA represents t-butanol.

In the present invention, when describing an ion exchange resin, the strong acid has the same meaning as that of the strong acid type.

The invention provides an olefin polymerization method, which comprises a first reaction zone and a second reaction zone, wherein the first reaction zone is filled with an olefin hydration catalyst, and the second reaction zone is filled with a solid phosphoric acid catalyst; the polymerization raw material and water enter a first reaction zone and react under the condition of olefin hydration; the discharge of the first reaction zone is used as the feed of a second reaction zone independently or together with the polymerization raw material, enters the second reaction zone and reacts under the condition of olefin polymerization; wherein the molar ratio of alcohol to water in the feed to the second reaction zone is 1: 1-20: the alcohol and water together act as an activator for the solid phosphoric acid catalyst in the second reaction zone.

According to the invention, an olefin hydration catalyst is provided in the first reaction zone. Any olefin hydration catalyst may be used as long as it does not depart from the object of the present invention. For example, the olefin hydration catalyst may be one or more selected from the group consisting of a strongly acidic cation exchange resin, a molecular sieve, a heteropolyacid and an acidic ionic liquid.

According to the present invention, the strongly acidic cation exchange resin catalyst may be one or more selected from the group consisting of a sulfonated styrene-divinylbenzene type resin, a sulfonated styrene-divinylbenzene type resin in which a part of hydrogen atoms on a benzene ring is substituted with chlorine, and a perfluorinated sulfonated styrene-divinylbenzene type resin. These types of resins are readily available from the market and can be prepared according to methods described in the classical literature. The sulfonated styrene-divinylbenzene resin is prepared through dropping the mixture of styrene and divinylbenzene into water phase system containing dispersant, initiator and pore creating agent under high speed stirring for suspension copolymerization, separating the obtained polymer beads from the system, extracting the pore creating agent from the polymer beads with solvent, sulfonating with dichloroethane as solvent and concentrated sulfuric acid as sulfonating agent, filtering, washing and other steps to obtain the product. Halogen atoms, such as fluorine, chlorine or bromine, are introduced into the skeleton of the common strong acid type ion exchange resin, so that the temperature resistance and the acid strength of the resin can be further improved. The strongly acidic high-temperature resistant resin containing halogen can be obtained by at least two ways, one way is to introduce halogen atoms, such as chlorine atoms, into benzene rings of a sulfonated styrene resin skeleton, and the strong electron-withdrawing effect of the halogen elements not only can stabilize the benzene rings, but also can improve the acidity of sulfonic acid groups on the benzene rings; the other approach replaces all hydrogen on the resin skeleton with fluorine, so that the fluorine has super-strong acidity and super-high thermal stability due to the strong electron-withdrawing property of the fluorine.

According to the invention, the mass exchange capacity of the strongly acidic cation exchange resin catalyst may be 3mmolH⁺/g～5.6mmolH⁺/g。

According to the invention, a solid phosphoric acid catalyst is provided in the second reaction zone. Any solid phosphoric acid catalyst may be used as long as it does not depart from the object of the present invention. The solid phosphoric acid catalyst is prepared from phosphoric acid and siliceous carrier such as silica gel, diatomite, kaolin, bentonite or organic diatomite. The common solid phosphoric acid catalyst is prepared with hot phosphoric acid and diatomite and through mixing, extruding, stoving, roasting, steam activation and other steps. The preparation and application of the solid phosphoric acid catalyst have been for more than 80 years, and the solid phosphoric acid catalyst can be conveniently purchased from the market or prepared according to the published documents.

According to the invention, the total phosphorus content of the solid phosphoric acid catalyst is P₂O₅The catalyst can be calculated by 50-70% of the total mass of the catalyst; amount of free phosphoric acid, in H₃PO₄The catalyst can be calculated by 16-20% of the total mass of the catalyst.

According to the invention, the polymerization feed and water are fed to the first reaction zone and reacted under olefin hydration conditions, and the molar ratio of alcohol to water in the feed to the second reaction zone can be controlled by controlling the conversion of said water. Unlike the existing olefin hydration technologies: in the olefin hydration reaction carried out by the invention, the conversion rate of the olefin is not required, but the conversion rate of the water added into the first reaction zone is controlled to be between 50 and 95 percent approximately. Unless further technical problems are posed, the present invention has no other limitations on the olefin composition, olefin content in the polymerization feed, and the amount of polymerization feed to be fed into the first reaction zone. For example, the olefin content in the raw material for lamination may be 10% -20%, 20% -30%, 30% -40%, 40% -50%, 50% -60%, 60% -70%, 70% -80%, 80% -90% or 90% -100%. As another example, the tertiary olefin content in the polymerization feedstock may be 2% -8%, 8% -10%, 10% -15%, 15% -25%, 25% -35%, 35% -45%, or 45% -60%. For another example, the amount of the raw material entering the first reaction zone may be 1% -2%, 2% -10%, 10% -20%, 20% -30%, 30% -50%, 50% -70%, 70% -90% or 90% -100% based on 100% of the total mass of the raw material.

According to the invention, the molar ratio of alcohol to water in the feed to the second reaction zone is 1: 1-10: 1, preferably 1: 1-6: 1, more preferably 1.5: 1-5: 1.

according to the present invention, in the first reaction zone, a portion of the water undergoes an olefin hydration reaction with the olefin in the polymerization feed, and the resulting alcohol and unreacted water together act as activators for the solid phosphoric acid catalyst in the second reaction zone. The appropriate amount of water to be added to the first reaction zone can be readily determined by one skilled in the art in light of the foregoing teachings of the present invention. Generally, the amount of water fed to the first reaction zone is from 0.01% to 5%, preferably from 0.1% to 1%, based on 100% of the total mass of the starting materials for the polymerization.

According to the invention, the feed to the first reaction zone is a polymerization feed and water, the molar ratio of olefin in the polymerization feed to the water may be 0.5: 1-5: 1.

according to one embodiment of the invention, in the first reaction zone, the olefin hydration catalyst is a strong acid cation exchange resin catalyst; the reaction temperature is 40-100 ℃; the reaction pressure is 0.5MPa to 10MPa, preferably 4MPa to 8 MPa.

According to the foregoing embodiment, the raw material for lamination entering the first reaction zone is 30% to 50%, 50% to 70%, 70% to 90%, or 90% to 100% based on 100% of the total mass of the raw material for lamination.

According to the foregoing embodiment, the tertiary olefin content in the raw material for lamination is 8% to 10%, 10% to 15%, 15% to 25%, 25% to 35%, or 35% to 45%.

According to the invention, the first reaction zone is operated continuously, and the mass space velocity of the feeding is 0.2h^－1～10h^－1。

According to the invention, the first reaction zone is composed of one or more reactors in the form of one or more selected from the group consisting of fixed bed reactors, tank reactors, tubular reactors and tower reactors, preferably fixed bed reactors.

According to the invention, the feed to the second reaction zone can be either the discharge from the first reaction zone or a mixture of the discharge from the first reaction zone and the raw materials for the superposition.

According to the invention, in the second reaction zone, the reaction temperature is 160-250 ℃, preferably 180-230 ℃; the reaction pressure is 2MPa to 10MPa, preferably 4MPa to 6 MPa.

According to the invention, the second reaction zone is composed of one or more reactors, and the form of the reactor is selected from one or more of a tank reactor and a fixed bed reactor, and is preferably a fixed bed reactor.

According to the invention, the second reaction zone is operated continuously, and the mass space velocity of the feeding is 0.5h^－1～20h^－1Preferably 0.5h^－1～5h^－1。

According to the present invention, the third reaction zone may or may not be provided.

When the third reaction zone is not provided, the superimposed product separated from the discharge of the second reaction zone can be directly used as a high-octane gasoline component.

When a third reaction zone is arranged, the discharge of the second reaction zone or a superposed product separated from the discharge enters the third reaction zone, and hydrogenation saturation is carried out in the third reaction zone; the superposed product after hydrogenation saturation is obtained after separation or not, and can be used as a high-octane gasoline component. The hydrogenation saturation of the product of the polymerization is prior art and is not described in detail in the present invention.

According to the invention, the raw material for the polymerization is C3-C6 olefin or a mixture of C3-C6 olefin and C3-C6 alkane. Specifically, it may be selected from propylene, propane, isobutylene, 1-butene, trans-2-butene, cis-2-butene, isobutane, 2-dimethylpropane, 3-methyl-1-butene, isopentane, 1-pentene, 2-methylbutene-1, n-pentane, trans-2-pentene, cis-2-pentene, 2-methyl-2-butene, 2-dimethylbutane, cyclopentene, 4-methyl-1-pentene, 3-methyl-1-pentene, cyclopentane, 2-methylpentane, 3-methylpentane, 2-methylpentene-1, n-hexane, 1-hexene, trans-3-hexene, 2-methyl-2-pentene and 3-methylcyclopentene.

According to the invention, the raw material for the polymerization is a mixture of propane and propylene, and the mass fraction of the propylene is 30-70%, preferably 40-60%.

According to the invention, the superimposed feedstock can be a propane dehydrogenation fraction, a refinery gas containing propylene and butylene, an isobutane dehydrogenation fraction, a catalytically cracked carbon four-fraction, a steam cracked carbon four-fraction, a catalytically cracked light gasoline or a steam cracked light gasoline.

According to one embodiment of the invention, the metal content in the raw lamination material is between 1 and 10. mu.g/g, preferably between 1.5 and 10. mu.g/g, more preferably between 2 and 6. mu.g/g.

According to one embodiment of the invention, the content of basic nitrogen compounds in the raw lamination material is 1 to 10. mu.g/g, preferably 1.5 to 10. mu.g/g, more preferably 2 to 6. mu.g/g.

According to the foregoing embodiment, the first reaction zone is filled with a strong acid cation exchange resin catalyst, which can effectively remove both metals and basic nitrides from the raw materials. Generally, the content of both metals and basic nitrides can be easily reduced to below 1. mu.g/g after the raw materials for lamination have passed through the first reaction zone.

The invention also provides a device for realizing the method, which is characterized by comprising a first reaction zone, a second reaction zone and a superposed raw material pipeline, wherein the first reaction zone is provided with an activating agent inlet, a reaction raw material inlet and a reaction product outlet, and the second reaction zone is provided with a reaction raw material inlet and a reaction product outlet; the reaction raw material inlet of the first reaction zone and the reaction raw material inlet of the second reaction zone are both connected with a superposed raw material pipeline; the reaction product outlet of the first reaction zone is connected with the reaction raw material inlet of the second reaction zone.

The first reaction zone is comprised of one or more fixed bed reactors. The first reaction zone is used for carrying out olefin hydration reaction.

The second reaction zone is composed of one or more fixed bed reactors, preferably 2-5 fixed bed reactors connected in series. The second reaction zone is used for carrying out olefin polymerization reaction.

The apparatus may be provided with or without a third reaction zone. When a third reaction zone is provided, the third reaction zone is used for carrying out hydrogenation saturation on the discharge of the second reaction zone or the superposed product separated from the discharge.

In one embodiment, the feed inlet of the third reaction zone is associated with the reaction product outlet of the second reaction zone.

In another embodiment, the apparatus is provided with a separation device for separating the output from the second reaction zone, and the feed inlet of the third reaction zone is connected to the superimposed product outlet of the separation device.

The apparatus may also be provided with a separation device for separating the discharge from the third reaction zone.

The invention is further illustrated with reference to the following examples, which are not to be construed as limiting the invention in any way.

Example 1

Referring to the process flow shown in FIG. 1, an experimental set-up was set up in a laboratory by connecting a first fixed bed reactor (i.e., a first reaction zone) having an inner diameter of 19mm and a length of 600mm in series with a second fixed bed reactor (i.e., a second reaction zone) having an inner diameter of 32mm and a length of 1000mmThe first fixed bed reactor is filled with 50mL KC110 type macroporous strong acid cation exchange resin (produced by Hebei Kerril environmental protection science and technology Co., Ltd., mass exchange capacity of 5.4 mmolH)⁺(water content: 35 m%), 200mL of RSPA-01 type supported solid phosphoric acid catalyst (produced by China petrochemical Long catalyst division, total phosphoric acid content: 65 m%, free phosphoric acid content: 18 m%) was charged into the second fixed bed reactor.

The mixed C4 (namely, a superimposed raw material) is taken from C four fraction of a catalytic cracking unit of a certain company, and the composition (mass fraction) of the C four fraction is as follows: propane 0.078%, propylene 0.035%, isobutane 33.796%, n-butane 14.220%, butylene 11.085%, n-butene 13.779%, isobutylene 20.425%, maleic 6.398%, 1, 3-butadiene 0.068%, C5 hydrocarbon 0.116%.

Introducing mixed C4 raw material into the first fixed bed reactor at the flow rate of 150g/h (mass space velocity of 1 h)^-1) And deionized water is introduced at the flow rate of 0.5g/h for reaction, the temperature of the first fixed bed reactor is controlled to be 60 ℃, and the pressure is controlled to be 6 MPa. The mixed carbon four raw material is introduced into the second fixed bed reactor at the speed of 50g/h, the mixed carbon four is mixed with the product at the outlet of the first fixed bed reactor, preheated to the reaction temperature (200 ℃) and then enters the second fixed bed reactor (the total mass space velocity is 1.25 h)^-1) The temperature of the second fixed bed reactor is controlled to be 200 ℃ and the pressure is controlled to be 5.8 MPa. The outlet of the raw material pump, the inlet and outlet of the first fixed bed reactor and the inlet and outlet of the second fixed bed reactor are all provided with online gas chromatography sampling, and the raw material composition, the material flow composition at the inlet and outlet of the first fixed bed reactor and the material flow composition at the inlet and outlet of the second fixed bed reactor can be analyzed by an online gas chromatograph. The reaction results were calculated from the analytical data and the total conversion of the polymerization was calculated according to the following formula. And measuring the pressure drop of the reactor by using a differential pressure gauge arranged at the inlet and the outlet of the second fixed bed reactor. The results of the 2-month run are shown in table 1.

TABLE 1

The experimental products were collected, after removal of unreacted carbon four by rectification, the oil was analyzed completely, the results are shown in table 2.

TABLE 2

Component name
		RON	102
Mercaptane sulfur, mg/kg	<3
		Water soluble acids or bases	Is free of
Copper sheet corrosion (50 ℃, 3h), grade	1a
		Initial cut point, DEG C	100.3
5% evaporation temperature, deg.C	105.4
		10% evaporation temperature, deg.C	107.1
30% evaporation temperature, deg.C	110.4
		50% evaporation temperature, deg.C	113.4
70% evaporation temperature, deg.C	118.4
		90% evaporation temperature, deg.C	171
95% evaporation temperature, deg.C	185
		End point of distillation,. degree.C	203
Induction period, min	65
		(unwashed) gum, mg/100mL	4.8
After washing, gum, mg/100mL	1.4
		Density at 20 ℃ in kg/m³	735.3
Vapor Pressure (RVPE), kPa	8.9
		Total sulfur mg/L	7.7

Comparative example 1

This comparative example differs from example 1 only in that the first fixed bed reactor was closed, and the mixed carbon four and water were mixed and preheated to the reaction temperature (200 ℃ C.) at flow rates of 200g/h and 0.5g/h, respectively, and then fed directly into the second fixed bed reactor. The other portions not mentioned in this comparative example were the same as in example 1. The results of the 2-month run are shown in table 3.

TABLE 3

The experimental products were collected and after removal of unreacted carbon four by rectification, the oil was analyzed completely, the results are shown in table 4.

TABLE 4

As can be seen from example 1 and comparative example 1, which is not provided with a first reaction zone according to the invention, but directly feeds the carbon four feedstock and water into a second reaction zone, shows that: the final distillation point of the superimposed oil product is obviously increased, the octane number is obviously reduced, and the pressure drop of the reactor is increased quickly.

Comparative example 2

The comparative example differs from comparative example 1 only in that the flow rate of water was 0.4 g/h. The results of the runs are shown in Table 5.

TABLE 5

The results of comparative example 2 and comparative example 1 show that, although lowering the water inflow retards the pressure rise of the reactor, the activator dosage does not reach the optimum value and the conversion of butene polymerization is significantly reduced.

Comparative example 3

The comparative example differs from example 1 only in that the first fixed bed reactor was closed, water was replaced with t-butanol, the mixed C4 feedstock and t-butanol were mixed and preheated to the reaction temperature (200 ℃ C.) at flow rates of 200g/h and 2.1g/h, respectively, and then fed directly to the second fixed bed reactor; the other portions not mentioned in this comparative example were the same as in example 1. The results of the 10-day run are shown in Table 6.

TABLE 6

Collecting experimental products, rectifying to remove unreacted carbon four, and performing total analysis on the oil product, wherein the result shows that the octane value RON99 of the oil product has a dry point of 215 ℃ and is beyond the range of gasoline.

The results of comparative example 3 show that when tert-butanol is used as the activator, the amount of the activator is large, the dry point of the product exceeds the standard, and the octane number is low.

Example 2

This example differs from example 1 only in that: all the carbon four raw materials enter the first fixed bed reactor, the flow rate is 200g/h, namely all the feeding materials of the second fixed bed reactor are the discharging materials of the first fixed bed reactor. The other portions not mentioned in this example are the same as those in example 1. The results of the 2-month run are shown in Table 7.

TABLE 7

Collecting experimental products, rectifying to remove unreacted carbon four, and performing total analysis on the oil product, wherein the result shows that the octane value RON103 of the oil product has a dry point of 201 ℃.

Example 3

Using the apparatus of example 1, a first fixed bed reactor (i.e., a first reaction zone) was charged with 50mL of D008 type macroporous strong acid cation exchange resin (produced by Kary environmental protection technology Co., Ltd., Hebei, mass exchange capacity of 4.0mmol H)⁺(g), the second fixed bed reactor (i.e., the second reaction zone) was charged with 200mL of a solid phosphoric acid catalyst (prepared from phosphoric acid and diatomaceous earth by a kneading bar extrusion method, total phosphoric acid content 66 m%, free phosphoric acid content 20 m%).

Feeding a mixture of the components in a first fixed bed reactor at a flow rate of 50g/h and a mass ratio of 1: 1, introducing deionized water at a flow rate of 0.5g/h to react, wherein the temperature of the first fixed bed reactor is controlled to be 60 ℃, and the pressure is controlled to be 6 MPa. Feeding into a second fixed bed reactor at a mass ratio of 150 g/h: 1, mixing the propylene-propane mixed raw material with the product flow at the outlet of the first fixed bed reactor, preheating the mixture to the reaction temperature (200 ℃), and then feeding the mixture into a second fixed bed reactor, wherein the temperature and the pressure of the second fixed bed reactor are controlled to be 200 ℃ and 5.8 MPa. The outlet of the raw material pump, the inlet and outlet of the first fixed bed reactor and the inlet and outlet of the second fixed bed reactor are all provided with online gas chromatography sampling, and the raw material composition, the material flow composition at the inlet and outlet of the first fixed bed reactor and the material flow composition at the inlet and outlet of the second fixed bed reactor can be analyzed by an online gas chromatograph. The reaction results were calculated from the analytical data and the total conversion of the polymerization was calculated according to the following formula. And measuring the pressure drop of the reactor by using a differential pressure gauge arranged at the inlet and the outlet of the second fixed bed reactor. The results of the 2-month run are shown in Table 8.

TABLE 8

Example 4

Clothes using example 1The first fixed bed reactor (i.e. the first reaction zone) is filled with 100mL KC110 type macroporous strong acid cation exchange resin (produced by Hebei Kerui environmental protection science and technology Co., Ltd., mass exchange capacity of 5.4mmol H⁺(g), the second fixed bed reactor (i.e., the second reaction zone) was charged with 200mL of RSPA-01 type supported solid phosphoric acid catalyst (produced by China petrochemical Long catalyst division, total phosphoric acid content 65 m%, free phosphoric acid content 18 m%).

Light gasoline is fed into the first fixed bed reactor at the flow rate of 50g/h, deionized water is fed into the first fixed bed reactor at the flow rate of 0.6g/h for reaction, the temperature of the first fixed bed reactor is controlled to be 90 ℃, and the pressure of the first fixed bed reactor is controlled to be 6 MPa. Light gasoline is introduced into the second fixed bed reactor at a rate of 150g/h, the light gasoline and the product at the outlet of the first fixed bed reactor are mixed and preheated to the reaction temperature (210 ℃) and then enter the second fixed bed reactor, and the temperature and the pressure of the second fixed bed reactor are controlled to be 210 ℃ and 5.0 MPa. The light gasoline composition is shown in Table 9. The outlet of the raw material pump, the inlet and outlet of the first fixed bed reactor and the inlet and outlet of the second fixed bed reactor are all provided with online gas chromatography sampling, and the raw material composition, the material flow composition at the inlet and outlet of the first fixed bed reactor and the material flow composition at the inlet and outlet of the second fixed bed reactor can be analyzed by an online gas chromatograph. The reaction results were calculated from the analytical data and the total conversion of the polymerization was calculated according to the following formula. And measuring the pressure drop of the reactor by using a differential pressure gauge arranged at the inlet and the outlet of the second fixed bed reactor. The results of the 2-month run are shown in Table 10.

TABLE 9 light gasoline blending stock composition

Name (R)	Carbon number	Mass fraction/%
			Isobutane	4	0.060
Butene (butylene)	4	0.690
			N-butane	4	1.003
Trans-butene-2	4	1.692
			2, 2-dimethylpropane	5	0.011
Cis-buten-2	4	1.117
			3-Methylbutene-1	5	0.310
Is unknown		0.025
			Isopentane	5	13.455
Pentene-1	5	1.041
			2-methylbutene-1	5	4.389
N-pentane	5	16.090
			Carbopentadienes	5	0.015
Trans-pentene-2	5	9.641
			Cis-pentene-2	5	3.391
2-methylbutene-2	5	16.315
			1, 3-pentadiene	5	0.016
1, 3-cyclopentadiene	5	0.464
			2, 2-dimethylbutane	6	0.199
Is unknown		0.012
			Cyclopentene	5	13.654
4-methylpentene-1	6	0.048
			3-methylpentene-1	6	0.039
Cyclopentane	5	10.974
			Is unknown		0.057
2-methylpentane	6	3.528
			3-methylpentane	6	0.856
2-methylpentene-1	6	0.221
			N-hexane	6	0.265
Trans-hexene-3	6	0.022
			Trans-hexene-2	6	0.025
2-methylpentene-2	6	0.073
			3-methylcyclopentene	6	0.117
Carbohexadienes	6	0.040
			Methylcyclopentane	6	0.019
Benzene and its derivatives	6	0.126
			Total up to		100.000

Watch 10

Example 5

This example illustrates the effect of the first reaction zone on the removal of metals and nitrogen compounds from the feed stream.

The device adopted in the embodiment is as follows: the first reactor (i.e., the first reaction zone) was a tubular reactor having an inner diameter of 32mm and a length of 1200mm, and filled with 500mL of a strongly acidic ion exchange resin catalyst (produced by Hebei Kairry environmental protection technology Co., Ltd., exchange capacity of 5.2mmol H)⁺/g)。

600g/h of mixed C-C (namely, a superimposed raw material) and 6g/h of tert-butyl alcohol are introduced into the first reactor to react at the temperature of 45 ℃ and the reaction pressure of 1.5 MPa. The composition of the laminating feed and the results of the operation of the reactor are shown in Table 11.

Table 11 table of physical distribution data of example 5

Number of commodity circulation	1	2	3
				Name of physical distribution	Carbon four feed	Tert-butanol feed	Discharge of the first reactor
Flow rate, g/h	600	6	606
				Temperature, C	45.00	45.00	45.00
Pressure, MPa	1.5	1.5	1.5
				Mass fraction
Isobutane	35.0000％	0.0000％	34.6535％
				N-butane	10.0000％	0.0000％	9.9010％
Isobutene	15.0000％	0.0000％	1.9307％
				1-butene	15.0000％	0.0000％	5.8995％
Cis-butenediol	9.9450％	0.0000％	9.3542％
				Butene of trans-butene	15.0000％	0.0000％	21.6832％
C8-TMP	0.0000％	0.0000％	11.9619％
				C8-DMH	0.0000％	0.0000％	1.8290％
C12-TIB	0.0000％	0.0000％	1.7822％
				C16-TEB	0.0000％	0.0000％	0.0000％
H₂O	0.0000％	0.0000％	0.0000％
				TBA	0.0000％	100.0000％	0.9901％
Metal cation	3μg/g		0.4μg/g
				Basic nitrogen compound	4μg/g		0.8μg/g

Claims

2. The process of claim 1 wherein the olefin hydration catalyst is selected from one or more of the group consisting of strongly acidic cation exchange resin catalysts, molecular sieve catalysts, heteropolyacid catalysts and acidic ionic liquid catalysts.

3. The method according to claim 2, wherein the strongly acidic cation exchange resin catalyst is one or more selected from the group consisting of a sulfonated styrene-divinylbenzene-type resin, a sulfonated styrene-divinylbenzene-type resin in which a part of hydrogen atoms on a benzene ring is substituted with chlorine, and a perfluorinated sulfonated styrene-divinylbenzene-type resin.

4. A process according to claim 2 or 3, wherein the mass exchange capacity of the strongly acidic cation exchange resin catalyst is 3mmolH⁺/g～5.6mmolH⁺/g。

5. The process of claim 1 wherein the solid phosphoric acid catalyst has a total phosphorus content, expressed as P₂O₅Calculated by 50 to 70 percent of the total mass of the catalyst; amount of free phosphoric acid, in H₃PO₄Calculated by 16 to 20 percent of the total mass of the catalyst.

6. The process of claim 1 wherein the molar ratio of alcohol to water in the feed to the second reaction zone is from 1: 1-10: 1, preferably 1: 1-6: 1.

7. the process according to claim 1, characterized in that the amount of water fed to the first reaction zone is between 0.01% and 5%, preferably between 0.1% and 1%, based on 100% of the total mass of the starting materials for the lamination.

8. The process according to claim 1, wherein the molar ratio of olefin in the polymerization feed to water introduced in the feed to the first reaction zone is 0.5: 1-5: 1.

9. the process of claim 1 wherein in the first reaction zone, the olefin hydration catalyst is a strong acid cation exchange resin catalyst; the reaction temperature is 40-100 ℃; the reaction pressure is 0.5 MPa-10 MPa.

10. A process according to claim 9, wherein the laminating feed to the first reaction zone is from 30% to 50%, from 50% to 70%, from 70% to 90% or from 90% to 100% based on 100% of the total mass of the laminating feed.

11. A process according to claim 9 or 10, wherein the tertiary olefin content of the raw lamination stock is from 8% to 10%, from 10% to 15%, from 15% to 25%, from 25% to 35% or from 35% to 45%.

12. The process of claim 1 wherein said first reaction zone is operated continuously and the mass space velocity of the feed is 0.2h^－1～10h^－1。

13. The process according to claim 1, wherein in the second reaction zone, the reaction temperature is 160 ℃ to 250 ℃, preferably 180 ℃ to 230 ℃; the reaction pressure is 2MPa to 10MPa, preferably 4MPa to 6 MPa.

14. The process of claim 1 wherein said second reaction zone is comprised of one or more fixed bed reactors.

15. The process of claim 1 wherein said second reaction zone is operated continuously with a mass space velocity of the feed of 0.5h^－1～20h^－1Preferably 0.5h^－1～5h^－1。

16. A process according to claim 1, wherein a third reaction zone is provided, the discharge from the second reaction zone or the superimposed product separated from the discharge being passed to the third reaction zone, and the hydrogenation saturation being carried out in the third reaction zone.

17. The process of claim 1 wherein said superimposed feedstock is selected from the group consisting of propane dehydrogenated distillate, refinery gas containing propylene and butylene, isobutane dehydrogenated carbon four-distillate, catalytically cracked carbon four-distillate, steam cracked carbon four-distillate, catalytically cracked light gasoline and steam cracked light gasoline.

18. The method according to claim 1, characterized in that the raw laminate has a metal content of 1 to 10 μ g/g and/or a basic nitrogen compound content of 1 to 10 μ g/g.

19. The device for olefin polymerization is characterized by comprising a first reaction zone, a second reaction zone and a polymerization raw material pipeline, wherein the first reaction zone is provided with an activating agent inlet, a reaction raw material inlet and a reaction product outlet, and the second reaction zone is provided with a reaction raw material inlet and a reaction product outlet; the reaction raw material inlet of the first reaction zone and the reaction raw material inlet of the second reaction zone are both connected with a superposed raw material pipeline; the reaction product outlet of the first reaction zone is connected with the reaction raw material inlet of the second reaction zone.