WO2017045489A1

WO2017045489A1 - Method and apparatus for alkylation of isoparaffin with olefin

Info

Publication number: WO2017045489A1
Application number: PCT/CN2016/092784
Authority: WO
Inventors: 魏小波; 韩海波
Original assignee: 中石化炼化工程（集团）股份有限公司
Priority date: 2015-09-18
Filing date: 2016-08-02
Publication date: 2017-03-23
Also published as: CN105061129A; CN105061129B

Abstract

Provided are a method and an apparatus for alkylation of an isoparaffin with an olefin. Steps of the alkylation method are: reacting an isoparaffin with an olefin in a group of microreactors with the presence of a catalyst, reaction conditions in the microreactors being a reaction temperature of 40°C to 200°C and a reaction pressure of 1.5 Mpa to 4.5 MPa; separating reaction products and obtaining a target reaction product, unreacted reactants, and the catalyst; re-feeding the unreacted reactants and the catalyst into the microreactors. The provided apparatus realizes continuous production, makes alkylation reaction rapid, greatly shortens a reaction time, improves the safety of the apparatus and selectiveness of the reaction process, and avoids occurrence of secondary reactions. There is no waste produced in the whole process, reducing costs and preventing pollution. In addition, because multiple reactors can be connected in parallel, simultaneous reactions can be realized by means of control, saving research and development costs for expanding a reaction scale, thereby further reducing costs.

Description

Method for alkylating isoparaffin and olefin and device thereof

Technical field

The present invention relates to the field of alkylation of isoparaffins and olefins, and in particular to a process for the alkylation of isoparaffins with olefins and apparatus therefor.

Background technique

The alkylation reaction process refers to a reaction process in which an alkyl group (methyl group, ethyl group, etc.) is introduced into a molecule of a compound. In the petroleum refining industry, it is generally referred to a process in which an isoparaffin is reacted with a C3-C5 olefin to form an alkylated oil. This alkylated oil is an important blending component of gasoline due to its high octane number, and as the environmental protection needs, the aromatic content of gasoline is increasingly restricted, which makes the alkylation process become more and more important.

There are two main alkylation processes currently used in the industry, namely the hydrofluoric acid process and the sulfuric acid process. The common disadvantages of these two methods are high acid consumption, unsafe use, severe corrosiveness and pollution, and the need for acid separation and acid recovery after the reaction. The cost of post-treatment is high, and thus to a large extent The increase in alkylation production capacity is limited. Since the 1960s, experts and scholars from all over the world have focused their attention on solid acid catalysts, hoping to develop a solid acid catalytic system that can replace the liquid acid catalytic process. There are also many patents related to this.

U.S. Pat. 4300015 discloses a catalyst for an alkylation reaction in which a macroporous molecular sieve is modified with a polyvalent metal ion to increase the activity and selectivity of the catalyst.

U.S. Pat. 5,816,626 discloses an isoparaffin-olefin alkylation process. The catalyst is a solid or liquid device divided into a reaction zone and a separation zone. The product is separated in the separation zone, and the temperature of the reaction zone is controlled at -30 ± 5 °C.

U.S. Pat. 5,849,976 discloses an isoparaffin-olefin alkylation catalyst which is a mobile bed alkylation catalyst employing a moving bed reaction regeneration system. The regeneration is carried out by a method of high temperature hydrogenation.

U.S. Pat. 5,304,698 discloses a solid acid catalyzed process for the alkylation of isoparaffin-olefins such that the entire reaction is carried out under supercritical conditions of the highest concentration of reactants to extend the useful life of the catalyst. However, due to the higher reaction temperature, the selectivity is lower than that of the liquid acid alkylation process, that is, the ratio of TMP (trimethylpentane) / DMH (dimethyl hexane) is low, and the alkane used. / olefin ratio is high, which limits the full utilization of alkanes to a certain extent.

USPat. 5,489,732 provides an alkylation process in which a solid homogeneous catalyst called HAL2100TM is used which has an optimized particle distribution and pore size and ensures good mass transfer. High alkylation activity for isoparaffins. Alkanes and olefins are fed separately, and isoparaffins and hydrogen are first introduced into the regeneration zone of the reactor to effect dissolution regeneration of the initially deactivated catalyst while inhibiting further deactivation thereof. After pretreatment, the olefin enters the riser along with the isoparaffin and the regenerated catalyst, and the alkylation reaction is mostly carried out in the riser. In the riser, the catalyst is rapidly separated from the hydrocarbons by gravity, and most of the catalyst enters the regenerative scrubbing zone of the reactor, a small portion is withdrawn through the side line, enters the regenerator, and is in contact with hydrogen at a higher temperature. In order to remove the heavy components deposited on the catalyst, the regenerated heavy components are returned to the bottom of the riser by gravity to react. After the mixture exiting the upper portion of the reactor is separated, the hydrocarbon phase enters the fractionation section, and the final product is fractionated, and the unreacted isoparaffin is recycled to the reactor for reaction.

The main side reaction of alkylation is the polymerization of olefins, and the production of olefin polymers is the main cause of catalyst deactivation. The above patents do not fundamentally solve this problem, so their common disadvantage is that the catalysts are deactivated quickly. The life expectancy is low, the reaction conditions of the reaction regeneration are different, and the energy consumption of the process system is high.

In view of this, the present invention has been specifically proposed.

Summary of the invention

A first object of the present invention is to provide a method for alkylating an isoparaffin with an olefin, the method of which is carried out in a microreactor, the reaction time is also greatly shortened, and the safety and reaction process of the apparatus are improved. Selectivity to avoid the occurrence of side reactions.

A second object of the present invention is to provide an apparatus for carrying out the method for alkylating an isoparaffin with an olefin, which allows the reaction to proceed continuously, is safe and effective, and produces no waste throughout the process.

In order to achieve the above object of the present invention, the following technical solutions are adopted:

A method for alkylating an isoparaffin with an olefin, comprising the steps of:

The isoparaffin and the olefin are reacted in the microreactor group under the action of a catalyst, and the reaction conditions of the microreactor are: a reaction temperature of 40-200 ° C, and a reaction pressure of 1.5-4.5 MPa;

The reaction product is separated to obtain a target reaction product, an unreacted reactant and a catalyst, respectively;

Unreacted reactants and catalysts re-enter the microreactor.

A microreactor is a three-dimensional structural unit made of a solid matrix that can be used for chemical reactions by means of special micromachining techniques. The average size of the internal unit structure width is on the order of micrometers, and usually contains fluid passages having an equivalent diameter of several tens to several hundreds of micrometers, and the overall size is on the order of centimeters.

For the reaction at the molecular level, the volume of the microreactor is very large, so its influence on the reaction mechanism and reaction kinetics is very small, its main role is to strengthen the mass and heat transfer process and the way of fluid flow. Improvement and other aspects.

Compared to conventional reactors, microreactors have the following main characteristics:

1. The line size is reduced. Within the microreactor, as the line scale decreases, the gradient of some physical quantities increases rapidly, such as temperature gradients, concentration gradients, pressure gradients, and density gradients, which are important for chemical reactions. An increase in the gradient will result in an increase in mass transfer and heat transfer driving forces, thereby expanding the diffusion flux per unit volume or unit area. These theories have been confirmed by a large number of microreactor mass transfer and heat transfer experiments. For example, in a micro heat exchanger, if the microchannel has a width of 50-500 μm and the rib width between the channels is 20-50 μm, the heat transfer coefficient of the micro device can reach 25 kW/(m2.K), which is Conventional heat exchangers are more than an order of magnitude larger. For example, the thickness of the fluid in the micro-mixer can be as small as several tens of micrometers, and the thickness of the fluid can be reduced to the nanometer scale by special design, so that the mixing time in the micro-mixer can be as small as milliseconds or even nanoseconds. , all of which are difficult to achieve with conventional equipment.

2. Increase in area to volume ratio. Within the microdevice, the corresponding area/volume ratio is significantly improved due to the reduced fluid thickness. Generally, the specific surface area in the microchannel device can reach 10,000 to 50,000 m ² /m ³ , while the specific surface area of conventional laboratory or industrial equipment does not exceed 1000 m ² /m ³ . In addition to enhancing heat transfer, the specific surface area can also enhance the reaction process. For example, a high-efficiency gas phase catalytic microreactor can adopt a structure in which a catalyst is coated on the inner surface of the microchannel. In addition, the increase of specific surface area is also very advantageous for some multi-phase processes. Even in the multi-phase system, as long as the thickness of one phase is controlled within the micro-scale, the purpose of strengthening mass transfer and heat transfer can be achieved. Theory and experiment The results all prove that the boundary area of the multiphase system in the microreactor can reach 5000-30000 m ² /m ³ . At present, the largest sector micro-reactor is a falling film type micro-reactor, which can reach the area bounded 25000m ² / m ^3, and the boundary area of conventional bubble column can only reach 100m ² / m ³ or so. If a circulation flow is employed in the microbubble column, the specific surface area can theoretically reach 50,000 m ² /m ³ or more.

3. The volume is reduced. Due to the reduction in line scale, the volume of the microreactor is drastically reduced, even as small as a few microliters. This difference is even more pronounced when a large-scale batch process is replaced with continuous micro-devices. For example, in an organometallic reaction process, if a microreactor is used, only 5 small reactors can be used instead of the original reactor, and the reaction volume can be reduced from 6000L to a few milliliters, and the reaction time is also greatly shortened and improved. Equipment safety and selectivity of the reaction process.

Since the structural characteristics of the microreactor are completely different from the conventional reactor, it is determined that the microreactor has unique advantages in the practical application of chemistry and chemical industry, mainly reflected in the following points:

(1) No amplification effect. Most fine chemical reactions use batch reactors. When the process is amplified from a small test process to a large reactor, due to the different mass transfer/heat transfer efficiency, the process conditions generally require a period of exploration, usually after a pilot test. Zoom into the big production. The amplification process of the microreactor is not achieved by increasing the feature size of the microchannel, but by increasing the number of microchannels.

(2) The reaction time can be precisely controlled. In the conventional one-pot reaction, in order to prevent the reaction from being too intense, the reactants are usually gradually added dropwise, which causes a part of the reactants to be added to stay too long. The reaction of most of the reactants, products or intermediates under reaction conditions for too long leads to the production of by-products. The microreactor technology takes a continuous flow reaction in the microchannel, which can precisely control the residence time of the material in the microchannel, and then pass to the next reaction or terminate the reaction immediately after the reaction reaches the optimal reaction time. This effectively suppresses the formation of by-products due to excessive reaction time.

(3) The reaction temperature can be precisely controlled. Since the microreactor has a large area/volume ratio, its high efficiency of heat exchange is determined, so that a large amount of heat released from the reaction can be removed to keep the reaction temperature uniform and constant. For the strong exothermic reaction, in the conventional reactor, due to the low mixing rate and heat exchange efficiency, local overheating often occurs, and local overheating often leads to the formation of by-products, thereby making the reaction Yield and selectivity decrease. In fine chemical production, if a large amount of heat generated by violent reaction cannot be exported in time, it may cause a material accident or even an explosion.

(4) Materials can be mixed instantaneously in precise proportions. In conventional reactors, the ratio of some of the fast-reacting materials is very strict. If the agitation is insufficient, a mismatch will occur locally to produce by-products. This phenomenon is almost unavoidable in conventional reactors, but in the microreactor system, the reaction channels are generally only a few tens of micrometers, and the materials can be mixed strictly according to the ratio, thereby avoiding the occurrence of side reactions.

The invention provides a method for alkylating an isoparaffin with an olefin, wherein the isoparaffin and the olefin are reacted in a microreactor under a specific reaction condition by a catalytic action of a particulate solid catalyst, the reaction is rapid, and the reaction time is greatly shortened. Moreover, the safety of the equipment and the selectivity of the reaction process are improved, and the occurrence of side reactions is avoided; the unreacted reactants and catalysts obtained after the reaction can be reused, no waste is generated, cost is saved, and pollution is prevented; The microreactors can be connected in parallel, and the reaction can be controlled at the same time, omitting the research and development expenses for expanding the reaction scale, and further saving the cost.

Preferably, the catalyst is any one or more of a catalyst composed of a molecular sieve, a solid super acid catalyst, and a supported heteropolyacid catalyst.

Further, the molecular sieve comprises: Y-type molecular sieve, ZSM-5, ZCM-22, USY, MCM-41, β-molecular sieve, mordenite and modified molecular sieve thereof.

The solid super acid catalyst refers to a multi-component solid super acid formed by adding metal oxides ZrO ₂ , TiO ₂ and Fe ₂ O ₃ as a matrix, adding other metals or oxides; and introducing rare earth element modification; A specific superfine acid is formed by a specific molecular sieve and a nano-sized metal oxide.

In order to ensure the flowability of the catalyst in the microreactor, it can flow in the reaction liquid to form a gas-liquid-solid slurry flow, and has good catalytic activity, preferably, the solid acid alkylation The particles of the catalyst are less than 20 μm and a suspension slurry having a solids content of less than 25% is formed in the alkane solution.

In order to more fully isoparaffin and olefin reaction, preferably, the isoparaffin and olefin ratio of alkane and alkene is 3-50: 1; space velocity of 1.1-1.3h ^-1.

In order to better recover the catalyst after the reaction and to maintain the activity of the recovered catalyst, the catalyst after the reaction is regenerated into the microreactor, and the regeneration treatment is carried out by supercritical extraction. Way of doing;

The operating conditions of the supercritical extraction are: temperature 135-150 ° C, pressure 3.7-4.0 MPa, extraction solvent is isoparaffin, mixing ratio of catalyst to extraction solvent is 1:3-4, extraction time is 5-100 minutes .

Further, the olefin polymer removed by the supercritical extraction is fractionated, fractionated to obtain an olefin polymer, and the extractant obtained by fractional distillation is recycled.

The method for alkylating an isoparaffin with an olefin provided by the invention is a continuous solid acid catalyst alkylation reaction regeneration process, which not only can maintain the activity and selectivity of the catalyst, but also prolong the service life, and the reaction can be carried out at the same time. Under lower alkane/ene ratio conditions, hydrogen regeneration is not required; the reaction time is short, which can effectively solve the regeneration problem of fast deactivated catalyst. Because the conditions of the reaction regeneration system are relatively close, the energy consumption of the process system is low, which is conducive to continuous operation. It can also realize rapid amplification and industrial application of the process.

The invention also provides an apparatus for implementing the above method, comprising:

Microreactor group: a microreactor group consisting of a plurality of microreactors in series for reacting isoparaffins and olefins under the action of a catalyst;

Flash tank: for separation of reaction products;

Alkyd oil storage tank: used to hold the target reaction product;

Wherein the outlet of the microreactor set is connected to the inlet of the flash tank, the outlet of the flash tank being connected to the inlet of the alkylated oil storage tank and the inlet of the microreactor set, respectively.

The device provided by the invention, the reaction product of the microreactor group is separated into a flash tank through a pipeline for separation, and the separated substances are passed through different pipelines into different equipment, wherein the target reaction product flows into the alkylation oil storage tank. The unreacted reactants and catalyst flow into the microreactor group to re-react. Achieve continuous production, high efficiency, and no waste discharge, energy saving and environmental protection.

Among them, the flash tank separates the gas liquid, and the gas is discharged from the top of the tank. The target reaction product is liquid into the alkylation oil storage tank, and the catalyst is solid and separated.

In order to facilitate the control of the amount of reactants, and in order to better separate the flash tank, the apparatus further comprises a mixing tank for mixing the isoparaffin with the catalyst, the outlet of the mixing tank and the micro The inlet connection of the reactor group;

A buffer tank is further disposed between the microreactor group and the flash tank.

The products in the microreactor group were discharged to a buffer tank which was metered into the flash tank in batches according to the requirements of the flash tank to allow the flash tank to better separate the product.

Preferably, the inlet of the mixing tank is connected to the outlet of the flash tank;

a sub-line is disposed between the mixing tank and the flash tank, and a regenerator for catalyst regeneration is disposed on the sub-line;

A rectification tank is connected to the outlet of the regenerator, and the fractionation tank is connected to a diesel storage tank.

In the reaction provided by the invention, the catalyst is deactivated slowly, and generally it is not necessary to regenerate all the catalysts at a time. Therefore, some of the catalysts can be directly returned to the mixing tank of the alkane and the catalyst mixture to carry out the catalytic reaction again, and the remaining catalyst. Then enter the regenerator to desorb regeneration. The ratio of catalyst regeneration and regeneration amount is adjusted depending on the activity, conversion rate, and selectivity of the catalyst. Further, depending on the situation, it is sometimes possible to return all of the catalyst directly to the mixing tank for catalytic reaction.

All or a part of the catalyst after the separation of the flash tank is driven by a small portion of unreacted reactants into the regenerator through the pipeline for desorption regeneration; the regenerated catalyst obtained in the regenerator Into the mixing tank; at the same time, the catalyst after the separation of the flash tank can also directly enter the mixing tank; the olefin polymer (coke precursor) is extracted from the regenerator, and enters the fractionation tank through the pipeline to realize the extractant and the olefin Separation of polymers, these olefin polymers are good diesel blending components, sent to diesel storage tanks, collected and then sent to the diesel hydrogenation unit or directly as a diesel blending component, and the fractionated extractant is recycled through the pipeline. Reaction.

Further, the number of the microreactor groups is one or more, and the microreactor groups are connected in parallel;

The number of microreactors in each of the microreactor groups is one or more.

Preferably, the number of the microreactor groups is from 1 to 50.

Preferably, the number of microreactors in each of the microreactor groups is 1-10.

An olefin such as a butene feed liquid is distributed in a ratio in a single microreactor in series in each microreactor group, reacted with an isoparaffin in the microreactor, and the reaction conditions are controlled. Improve the selectivity of the reaction process and reduce the occurrence of side reactions.

Each microreactor group may be composed of a plurality of microreactors in series, and the number of microreactors connected in series may be 1, 2, 3, ... n (n = 10), one of the microreactor groups The number can be one, or two, four, three, four, five, 50, and so on.

The present invention does not limit the form of the microreactor as long as it allows the solid particles to flow in the reactor, i.e., allows the gas-liquid-solid three-phase to flow.

Compared with the prior art, the beneficial effects of the present invention are:

(1) The method for alkylating an isoparaffin and an olefin provided by the present invention, reacting in a microreactor under specific reaction conditions, the reaction is rapid, the reaction time is greatly shortened, and the safety of the device and the reaction process are improved. Selectivity, avoid the occurrence of side reactions; unreacted reactants and catalysts obtained after the reaction can be reused, no waste is generated, cost is saved, and pollution is prevented.

(2) The method for alkylating an isoparaffin and an olefin provided by the present invention, wherein the microreactor can be connected in series, and the microreactor group can be formed by paralleling a plurality of microreactor groups, and the reaction can be simultaneously performed under controlled conditions. The development expenses for expanding the response are omitted, and the cost is further saved.

(3) The present invention also specifically limits the types and parameters of the catalyst to facilitate continuous production.

(4) The present invention also limits the alkene ratio of the isoparaffin and the olefin, and the rate of introduction to make the isoparaffin and olefin more fully and more efficiently reacted.

(5) The present invention also provides supercritical extraction and regeneration conditions of the catalyst, the catalyst regeneration operation is simple, the catalyst recovery efficiency is high, and the recovered catalyst maintains good activity.

(6) The present invention also provides an apparatus for carrying out a method for alkylating an isoparaffin with an olefin, which realizes continuous production, has high efficiency, and has no waste discharge in the entire process, and is energy-saving and environmentally friendly.

DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art description will be briefly described below.

1 is a schematic view of an apparatus for carrying out an alkylation method according to an embodiment of the present invention;

2 is a schematic diagram of a microreactor set provided by an embodiment of the present invention;

Reference mark:

Mixing tank 2, microreactor group 5, buffer tank 7, flash tank 9, regenerator 13, alkylated oil storage tank 17, fractionation tank 18, diesel storage tank 20, catalyst tank 22, microreactor 511-514

Lines

1, 3, 4, 6, 8, 10-12, 14-16, 19, 21, 23, branch line 31 of line 3, branch line 41-44 of line 4.

detailed description

The embodiments of the present invention will be described in detail below with reference to the embodiments, but those skilled in the art will understand that the following examples are only used to illustrate the invention and should not be construed as limiting the invention. Wai. Those who do not specify the specific conditions in the examples are carried out according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are conventional products which are commercially available.

Example 1

The method for alkylation of isoparaffins with olefins is as follows:

The isoparaffin is mixed with a catalyst composed of solid Y-type molecular sieve and then passed into a microreactor, and an olefin is introduced at the same time. The alkene ratio of the isoparaffin to the olefin is 3:1, and the reaction space velocity is 1.1 h ^-1 ;

The solid Y-type molecular sieve catalyst has a particle size of less than 20 μm, and a suspension slurry having a solid content of less than 25% is formed in the alkane solution;

The reaction conditions for controlling the microreactor are: a reaction temperature of 100 ° C, and a reaction pressure of 1.5 MPa;

The reacted product is separated to obtain a target reaction product, an unreacted reactant and a catalyst, respectively;

The unreacted reactant is directly passed into the microreactor to continue the reaction;

After supercritical extraction, the catalyst is remixed with the isoparaffin and then passed to the microreactor for reaction;

The reaction conditions of the supercritical extraction are: temperature 135 ° C, pressure 4.0 MPa, the extraction solvent is isoparaffin, the mixing ratio of the catalyst and the extraction solvent is 1:3, and the extraction time is 30 minutes;

The olefin polymer removed by the supercritical extraction is fractionated, fractionated to obtain an olefin polymer, and the extractant obtained by fractional distillation is recycled.

The method for alkylating an isoparaffin and an olefin provided by the invention is carried out in a microreactor, and the range of the control range of the reaction temperature is changed from 2-15 ° C of the sulfuric acid method to 0.5-2 ° C, and the reaction is stable and rapid. after the reaction; olefin space velocity was increased from 0.3h ^-1 to 1.1h ^-1, greatly reducing the reaction time, productivity increased by 62%, and selectivity is improved and the safety of the reaction apparatus, to avoid side reactions The obtained unreacted reactants and catalyst can be reused, saving cost; the whole reaction process is continuously produced, no waste is generated, and energy saving and environmental protection are achieved.

Example 2

The method for alkylation of isoparaffins with olefins is as follows:

The isoparaffin is mixed with the solid super acid catalyst and then passed into the microreactor, and the olefin is introduced at the same time. The alkene ratio of the isoparaffin to the olefin is 10:1, and the reaction space velocity is 1.2 h ^-1 ;

The solid acid alkylation catalyst has a particle size of less than 20 μm and a suspension slurry having a solid content of 20% in the alkane solution;

The reaction conditions for controlling the microreactor are: reaction temperature 40 ° C, reaction pressure 4.5 MPa;

The reaction conditions of the supercritical extraction are: temperature 150 ° C, pressure 3.7 MPa, the extraction solvent is isoparaffin, the mixing ratio of the catalyst and the extraction solvent is 1:4, and the extraction time is 60 minutes;

The method for alkylating an isoparaffin and an olefin provided by the invention is carried out in a microreactor, and the range of the control range of the reaction temperature is changed from 2-15 ° C of the sulfuric acid method to 0.5-2 ° C, and the reaction is stable and rapid. olefin space velocity is increased from 0.3h ^-1 to 1.2h ^-1, greatly reducing the reaction time, increase production efficiency, and selectivity is improved and the safety of the reaction apparatus, to avoid side reactions; obtained after the reaction is not The reactants and catalysts of the reaction can be reused, saving cost; the whole reaction process is continuously produced, no waste is generated, and energy saving and environmental protection are achieved.

Example 3

The method for alkylation of isoparaffins with olefins is as follows:

The isoparaffin is mixed with the solid super acid catalyst and then passed into the microreactor, and the olefin is introduced at the same time. The alkene ratio of the isoparaffin to the olefin is 50:1, and the reaction space velocity is 1.3 h ^-1 ;

The solid acid alkylation catalyst has a particle size of less than 20 μm and a suspension slurry having a solid content of 15% in the alkane solution;

The reaction conditions for controlling the microreactor are: a reaction temperature of 200 ° C, and a reaction pressure of 1.5 MPa;

After supercritical fluid extraction, the catalyst is re-introduced into the microreactor for reaction;

The reaction conditions of the supercritical extraction are: temperature 140 ° C, pressure 3.7 MPa, the extraction solvent is isoparaffin, the mixing ratio of the catalyst and the extraction solvent is 1:4, and the extraction time is 5 minutes;

The method for alkylating an isoparaffin and an olefin provided by the invention is carried out in a microreactor, and the range of the control range of the reaction temperature is changed from 2-15 ° C of the sulfuric acid method to 0.5-2 ° C, and the reaction is stable and rapid. The space velocity of olefins is greatly increased, the reaction time is greatly shortened, the production efficiency is improved, the safety of the equipment and the selectivity of the reaction process are improved, and the occurrence of side reactions is avoided; the unreacted reactants and catalysts obtained after the reaction can be reused. , cost saving; continuous production of the entire reaction process, no waste generation, energy saving and environmental protection.

Example 4

The method for alkylation of isoparaffins with olefins is as follows:

Isoparaffin ZCM-22 with a solid catalyst are mixed and nuanced mordenite through the reactor, while passing the olefin, isoparaffin and olefin ratio of alkane and alkene 20: 1, space velocity of 1.3h ^-1;

The catalyst consisting of solid ZCM-22 and mordenite has a particle size of less than 20 μm and a suspension slurry having a solid content of 10% is formed in the alkane solution;

The reaction conditions for controlling the microreactor are: reaction temperature 80 ° C, reaction pressure 4 MPa;

The reaction conditions of the supercritical extraction are: a temperature of 140 ° C, a pressure of 3.8 MPa, an extraction solvent of an isoparaffin, a mixing ratio of the catalyst to the extraction solvent of 1:3.5, and an extraction time of 100 minutes;

Example 5

The method for alkylation of isoparaffins with olefins is as follows:

The isoparaffin is mixed with the supported heteropolyacid catalyst and the solid super acid catalyst, and then introduced into the microreactor, and the olefin is introduced at the same time. The alkene ratio of the isoparaffin to the olefin is 20:1, and the reaction space velocity is 1.2 h ^-1 ;

The solid acid alkylation catalyst has a particle size of less than 20 μm and forms a suspension slurry having a solid content of 5% in the alkane solution;

The reaction conditions for controlling the microreactor are: a reaction temperature of 150 ° C, and a reaction pressure of 2.5 MPa;

The reaction conditions of the supercritical extraction are: temperature 150 ° C, pressure 3.7 MPa, the extraction solvent is isoparaffin, the mixing ratio of the catalyst and the extraction solvent is 1:4, and the extraction time is 40 minutes;

Example 6

The method for alkylation of isoparaffins with olefins is as follows:

The isoparaffin is mixed with the β-molecular sieve catalyst, the solid super acid catalyst and the supported heteropolyacid catalyst, and then introduced into the microreactor, and the olefin is introduced at the same time, and the alkene ratio of the isoparaffin and the olefin is 20:1. a space velocity of 1.2h ^-1;

The solid acid alkylation catalyst has a particle size of less than 20 μm and forms a suspension slurry having a solid content of 12% in the alkane solution;

The reaction conditions for controlling the microreactor are: reaction temperature 100 ° C, reaction pressure 3.0 MPa;

The reaction conditions of the supercritical extraction are: temperature 140 ° C, pressure 3.9 MPa, the extraction solvent is isoparaffin, the mixing ratio of the catalyst to the extraction solvent is 1:3.5, and the extraction time is 100 minutes;

Example 7

The alkylation process of the isoparaffins and olefins in Examples 1-6 can be carried out in the following apparatus.

As shown in Figure 1, the present invention also provides an apparatus for carrying out a method for alkylating an isoparaffin with an olefin, comprising:

Microreactor group 5: for the reaction of isoparaffins and olefins under the action of a catalyst;

Flash tank 9: for separation of reaction products;

Alkyd oil storage tank 17: for containing the target reaction product;

Wherein the outlet of the microreactor group 5 is connected to the inlet of the flash tank 9, the outlet of the flash tank 9 is respectively associated with the inlet of the alkylated oil storage tank 17 and the microreactor group 5 Entrance connection.

According to the apparatus provided by the present invention, the reaction product of the microreactor group 5 is separated into the flash tank 9 through the line 6 for separation, and the separated substances are passed through different lines to different apparatuses, wherein the target reaction product flows through the line 11. Alkyd oil storage tank 17, unreacted reactants and catalyst influx Reactor group 5 was re-reacted. Achieve continuous production, high efficiency, and no waste discharge, energy saving and environmental protection.

Among them, the flash tank 9 separates the gas liquid, the gas is discharged from the top of the tank, and the target reaction product is liquid into the alkylated oil storage tank 17, and the catalyst is solid and is also separated.

In order to facilitate the control of the amount of reactants, and at the same time, in order to better separate the flash tank 9, the apparatus further comprises a mixing tank 2 for mixing the isoparaffin with the catalyst, the outlet of the mixing tank 2 and The inlet of the microreactor group 5 is connected;

A buffer tank 7 is further disposed between the microreactor group 5 and the flash tank 9.

The product after the reaction in the microreactor group 5 is discharged to the buffer tank 7 through the line 6, and the buffer tank 7 quantitatively flows the product into the flash tank 9 in batches according to the demand of the flash tank, so that the flash tank 9 is better The product is isolated.

Preferably, the inlet of the mixing tank 2 is connected to the outlet of the flash tank 9;

Between the mixing tank 2 and the flash tank 9 is provided a sub-line 12, the sub-line 12 is provided with a regenerator 13 for catalyst regeneration;

The outlet of the regenerator 13 is connected to a fractionation tank 18 via a line 16, which is connected to a diesel storage tank 20 via a line 19.

In the reaction provided by the invention, the catalyst is deactivated slowly, and generally no regeneration treatment is required for each of the catalysts. Therefore, some of the catalyst can be directly returned to the mixing tank 2, ready for the catalytic reaction, and the remaining catalyst is recycled. The device 13 is desorbed and regenerated. The ratio of catalyst regeneration and regeneration amount is adjusted depending on the activity, conversion rate, and selectivity of the catalyst. In addition, depending on the situation, it is sometimes possible to return all of the catalyst directly to the mixing tank 2 for mixing; of course, it is also possible that all of the catalyst enters the regenerator and is desorbed and regenerated, directly returned to the mixing tank 2 for mixing, and then enters the microreactor group. The catalytic reaction is carried out.

All or a part of the catalyst after the separation of the flash tank 9 is driven by a small portion of unreacted reactants into the regenerator 13 via line 12 for desorption regeneration; the regenerated catalyst obtained in the regenerator 13 passes through the pipeline. 15 enters the mixing tank 2; at the same time, the catalyst separated by the flash tank 9 can also enter the mixing tank 2 directly through the line 14; the olefin polymer (coke precursor) is removed from the regenerator 13 through the pipeline 16 The separation agent is separated from the olefin polymer. The olefin polymer is a good diesel blending component. After separation, it is sent to the diesel storage tank 20 via line 19. After being collected, it can be sent to the diesel hydrogenation unit or directly. As a diesel blending component, a portion of the extractant fractionated is returned to the regenerator 13 via line 21.

Further, the number of the microreactor groups 5 is one or more, and the microreactor groups 5 are connected in parallel;

The number of microreactors in each of the microreactor groups 5 is one or more.

Preferably, the number of the microreactor groups 5 is from 1 to 50.

Preferably, the number of microreactors in each of said microreactor groups 5 is from 1 to 10.

The amount of reactant added per microreactor group 5 was controlled by different lines, and by controlling the reaction conditions of the microreactor group 5, different microreactor groups 5 were simultaneously reacted.

Specifically, the isoparaffin feedstock enters the mixing tank 2 through line 1, and the catalyst of the catalyst storage tank 23 enters the mixing tank 2 through line 24, and the two are mixed in a certain ratio in the mixing tank 2 to form a heterogeneous catalyst-containing particle. An alkane suspension which is separately aliquoted via line 3 into a first feed inlet of a plurality of (1-n) parallel microreactor groups 5 of the first microreactor; and another feedstock olefin (eg The butene) liquid enters each microreactor group 5 by the number of microreactor groups in line 4; in each microreactor group 5, it enters the series in a certain proportion. n microreactors first microreactor second feed inlet, second microreactor second feed inlet, third microreactor second feed inlet, etc.;

Specifically, as shown in FIG. 2, one microreactor group includes four microreactors, and the suspension of the isoparaffin raw material and the catalyst enters the

series microreactors

511 and 512 through the branch line 31 of the pipeline 3, respectively. 513, 514; the raw material olefins are passed into the micro-reactors 511, 512, 513, and 514 through the

branch lines

41, 42, 43, and 44 of the line 4, respectively, to sufficiently carry out the reaction.

By controlling the ratio and conditions of the reaction raw materials, the microreactor in series firstly introduces a suspension of the isoparaffin raw material and the catalyst, and then separately feeds the raw materials olefin in each reactor, so that the respective reactants and the solid suspended catalyst are More complete reaction in the microreactor, reduce the occurrence of side reactions, increase the conversion of olefins, and take heat through the exchange medium of the interlayer of the microreactor to control the reaction temperature, greatly reducing the fluctuation of the reaction temperature of the microreactor range. After the reaction, the unreacted reactants, reaction products, together with the catalyst, enter the buffer tank 7 from line 6, pass through the line 8 into the flash tank 9 through the regulated pressure, and the unreacted reactants are returned to the microreactor via the line 10, the target reaction The product liquid enters the alkylated oil storage tank 17 via line 11. All or a portion of the catalyst after the substantially separation of the flash tank 9 is fed, via a small amount of unreacted reactants, through a line 12 to a regenerator 13 in which the isoparaffin is in a supercritical state for desorption regeneration. Under the supercritical condition of the reactant isoparaffin, the isoparaffin is used as an extractant to extract and desorb the olefin polymer (coke precursor) adsorbed on the surface of the catalyst under supercritical conditions, and the extract is separated from the catalyst. The regenerated catalyst is repressurized or depressurized and then passed through line 15 to the mixing tank 2; a portion of the unregenerated catalyst from the flash tank 9 is directly fed into the mixing tank 2 from the line 14 for mixing; The tank 22 outputs a catalyst to the mixing tank 2 through a line 23 to replenish the catalyst, and the obtained catalyst isoparaffin suspension is sent back to the microreactor through the line 3 to be mixed with the olefin in stages, thereby achieving continuous reaction regeneration.

The extracted olefin polymer (coke precursor) is sent to a fractionation tank 18 via line 16 to separate the extractant from the olefin polymer. These olefin polymers are good diesel blending components and are fed to the diesel via line 19. The storage tank 20 can be sent to the diesel hydrogenation unit after being collected or directly discharged as a diesel blending component, and the fractionated extractant is returned to the microreactor reaction via the line 21.

Each microreactor group may be composed of n microreactors in series, and the number of microreactors connected in series may be 2, 3, ... n (n=10), and the number of microreactor groups may be 1 or 2, 3, 4, 5, 50, etc.

The present invention does not limit the form of the microreactor as long as solid particles can be allowed to flow in the reactor.

While the invention has been illustrated and described with reference to the embodiments of the present invention, it will be understood that many modifications and changes can be made without departing from the spirit and scope of the invention. Accordingly, it is intended to embrace in the appended claims

Claims

A method for alkylating an isoparaffin with an olefin, characterized by comprising the steps of:

The isoparaffin and the olefin are reacted in a microreactor under the action of a catalyst, and the reaction conditions of the microreactor are: a reaction temperature of 40-200 ° C, and a reaction pressure of 1.5-4.5 MPa;

The reaction product is separated to obtain a target reaction product, an unreacted reactant and a catalyst, respectively;

Unreacted reactants and catalysts re-enter the microreactor.
The alkylation process according to claim 1, wherein the catalyst is any one or more of a catalyst composed of a molecular sieve, a solid super acid catalyst, and a supported heteropolyacid catalyst.
The alkylation method according to claim 2, wherein the molecular sieve comprises: Y type molecular sieve, ZSM-5, ZCM-22, USY, MCM-41, β-molecular sieve, mordenite and modified molecular sieve thereof .
The alkylation process according to claim 2, wherein the solid acid alkylation catalyst has a particle size of less than 20 μm and a suspension slurry having a solid content of less than 25% is formed in the alkane solution.
The alkylation process according to claim 1, wherein the isoparaffin and the olefin have an alkene ratio of from 3 to 50:1; and the reaction space velocity is from 1.1 to 1.3 h -1 .
The alkylation method according to claim 1, wherein the reacted catalyst is reprocessed into the microreactor after the regeneration treatment, and the regeneration treatment is carried out by supercritical extraction;

The operating conditions of the supercritical extraction are: temperature 135-150 ° C, pressure 3.7-4.0 MPa, extraction solvent is isoparaffin, mixing ratio of catalyst to extraction solvent is 1:3-4, extraction time is 5-100 minutes ;

Preferably, the olefin polymer removed by the supercritical extraction is fractionated, fractionated to obtain an olefin polymer, and the extractant obtained by fractional distillation is recycled.
Apparatus for carrying out the alkylation process according to any one of claims 1 to 6, comprising:

Microreactor group: a microreactor group consisting of a plurality of microreactors in series for reacting isoparaffins and olefins under the action of a catalyst;

Flash tank: for separation of reaction products;

Alkyd oil storage tank: used to hold the target reaction product;

Wherein the outlet of the microreactor set is connected to the inlet of the flash tank, the outlet of the flash tank being connected to the inlet of the alkylated oil storage tank and the inlet of the microreactor set, respectively.
The apparatus according to claim 7, further comprising a mixing tank for mixing the isoparaffin with the catalyst, the outlet of the mixing tank being connected to the inlet of the microreactor;

A buffer tank is further disposed between the microreactor group and the flash tank.
The apparatus according to claim 8, wherein an inlet of said mixing tank is connected to an outlet of said flash tank;

a sub-line is disposed between the mixing tank and the flash tank, and a regenerator for catalyst regeneration is disposed on the sub-line;

A rectification tank is connected to the outlet of the regenerator, and the fractionation tank is connected to a diesel storage tank.
The apparatus according to any one of claims 7 to 9, wherein the number of the microreactor groups is one or more, and the microreactor groups are connected in parallel;

The number of microreactors in each of the microreactor groups is one or more;

The number of the microreactor groups is preferably from 1 to 50;

The number of microreactors connected in series in each of the microreactor groups is preferably from 1 to 10.