Microreactor and production device of poly-alpha-olefin base oil

Abstract

The utility model discloses a microreactor and a production device of poly-alpha-olefin base oil. The microreactor comprises a first fluid layer (1), a diffusion layer (2), a reaction layer (3) and a heat exchange layer (4) which are sequentially arranged, wherein the first fluid layer is communicated with the reaction layer through the diffusion layer, the reaction layer is not communicated with the heat exchange layer, the first fluid layer is provided with a first fluid inlet (6), and two ends of the reaction layer are respectively provided with a second fluid inlet (7) and a product outlet (12); a heat exchange medium inlet (8) and a heat exchange medium outlet (9) are formed in the two ends of the heat exchange layer respectively. The micro-reactor disclosed by the utility model is used for the mixed reaction process of gas-liquid, gas-liquid-liquid and other multi-phase fluids, the reaction system is good in mixing effect, and the conversion rate and the target product selectivity are increased. The production device of the poly-alpha-olefin base oil is suitable for producing the poly-alpha-olefin base oil through continuous reaction of synthesis gas.

Description

Technical Field

[0001] The utility model relates to a microreactor and an olefin polymerization reaction device. Background Art

[0002] Due to their small spatial characteristic dimensions and large specific surface area, microreactors have excellent mass and heat transfer effects and heat exchange capabilities, and can accurately control reaction time and temperature. They have great application potential, such as in polyalphaolefin synthesis, liquefied gas desulfurization, Fischer-Tropsch synthesis, and hydrogenation processes.

[0003] When scaling up microreactors for processing capacities exceeding 10,000 tons, the primary approach is to increase the number of channels. Because the dimensions of individual channels in a microreactor vary minimally, there is no inherent scaling effect. However, as the number of channels increases, distributing reactants and heat exchange fluids among the corresponding channels in pilot-scale and industrial-scale microreactors becomes a challenge.

[0004] CN108003938A discloses a system and method for converting biomass feedstock into lubricant base oil. The microreactor used in Fischer-Tropsch synthesis has a three-dimensional channel structure, with n parallel reaction channels forming a single reaction channel layer, m parallel fluid channels forming a single fluid channel layer, and x reaction channel layers and y fluid channel layers forming an interlaced three-dimensional channel structure. The channel distribution method of this reactor is suitable for gas-phase reaction systems. In a heat exchange structure, when the heat exchange medium is liquid and the number of channels is large, the heat exchange fluid will be difficult to distribute uniformly among the channels.

[0005] CN106635117A discloses a Fischer-Tropsch synthesis reaction method. After the synthesis gas is dispersed into bubbles by a fluid dispersion structure, it enters a mixer and is fully mixed with a catalytic liquid containing a nanocatalyst. The mixed reactant flows through a logistics inlet into the reaction microchannel of a microreactor to undergo a Fischer-Tropsch synthesis reaction to generate hydrocarbon products. The heat generated by the reaction is released by heat exchange with the heat exchange medium in the heat exchange microchannel. This structure is more suitable for systems with relatively low reaction speeds. If the reactants and catalysts start to react quickly after mixing, the time required for the reaction fluid to be mixed into the distribution chamber and distribution components is long, and the heat is difficult to remove quickly, which will directly affect the product quality. Utility Model Content

[0006] The technical problem to be solved by the utility model is to provide a microreactor for olefin polymerization and a polyalphaolefin base oil production device, which can produce polyalphaolefin base oil by using synthesis gas through Fischer-Tropsch reaction and polymerization reaction.

[0007] In the first aspect, the utility model provides a microreactor, comprising a first fluid layer, a diffusion layer, a reaction layer and a heat exchange layer arranged in sequence; wherein, the first fluid layer is connected to the reaction layer through the diffusion layer, and the reaction layer is not connected to the heat exchange layer, the first fluid layer is provided with a first fluid inlet, and the reaction layer is provided with a second fluid inlet and a product outlet at both ends; the heat exchange layer is provided with a heat exchange medium inlet and a heat exchange medium outlet at both ends.

[0008] In the second aspect, the production device of polyalphaolefin base oil provided by the utility model includes a Fischer-Tropsch microreactor, a first distillation tower, a second distillation tower, a polymerization microreactor, a centrifugal separator and a third distillation tower connected in sequence, and the polymerization microreactor is the above-mentioned microreactor; wherein, the side line discharge of the second distillation tower is connected to the second fluid inlet of the polymerization microreactor, the product outlet of the polymerization microreactor is connected to the centrifugal separator, and the light material outlet of the centrifugal separator is connected to the third distillation tower.

[0009] Preferably, the heavy material outlet of the centrifugal separator is connected to the first fluid inlet of the polymerization microreactor.

[0010] The beneficial effects of the microreactor and the polyalphaolefin base oil production device provided by the utility model are:

[0011] The microreactor provided by the utility model is used for gas-liquid, gas-liquid-liquid and other multiphase fluid mixing reaction processes. It is suitable for α-olefin polymerization reactions, with good mixing effect of reactants and catalysts, uniform distribution of the reaction system in the reaction layer, and increased conversion rate and target product selectivity.

[0012] The production device of polyalphaolefin base oil provided by the utility model is suitable for generating polyalphaolefin base oil by continuous reaction of synthesis gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0014] Figure 1 This is a schematic structural diagram of the microreactor provided by the utility model.

[0015] Figure 2 Schematic diagram of the structure of the reaction layer in one embodiment of the microreactor.

[0016] Figure 3 Schematic diagram of the structure of the reaction layer in the second embodiment of the microreactor.

[0017] Figure 4 Schematic diagram of the internal components in the second embodiment of the microreactor at sections aa and bb.

[0018] Figure 5 This is a schematic diagram of the process of a production unit for polyalphaolefin base oil.

[0019] Figure 6 This is a top view of the central section of the Fischer-Tropsch microreactor.

[0020] Figure 7 This is a central cross-sectional side view of the Fischer-Tropsch microreactor.

[0021] in:

[0022] 1-First fluid layer 2-Diffusion layer 3-Reaction layer

[0023] 4-heat exchange layer 5-mixer 6-first fluid inlet

[0024] 7- Second fluid inlet 8- Heat exchange medium inlet 9- Heat exchange medium outlet

[0025] 10- Third fluid inlet 11- Fourth fluid inlet 12- Product outlet

[0026] 13- baffle 14- baffle channel 15- internal component

[0027] 20-Fischer-Tropsch microreactor 21-first distillation tower 22-second distillation tower

[0028] 23-polymerization microreactor 24-centrifugal separator 25-third distillation tower

[0029] 26-Synthesis gas inlet 28-Fischer-Tropsch crude product 29-Polyolefin feedstock

[0030] 30-polymerization product 31-catalyst circulation pipeline 32-target product

[0031] 33-Byproduct

[0032] 101-heat exchange medium inlet 102-heat exchange strengthening component 103-heat exchange channel

[0033] 104-heat exchange medium outlet 105-reaction channel 106-microreactor shell

[0034] 107-heat exchange medium distribution chamber 108-heat exchange medium collection chamber 109-reactant distribution chamber

[0035] 109-Product Collection Chamber 27-Exit DETAILED DESCRIPTION

[0036] The following is a detailed description of the specific embodiments of the present invention. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0037] In the present invention, unless otherwise specified, the directions or positional relationships indicated by directional words such as "up, down, left, right, inside, outside, top, bottom" are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0038] In the first aspect, the utility model provides a microreactor, comprising a first fluid layer 1, a diffusion layer 2, a reaction layer 3 and a heat exchange layer 4 arranged in sequence; wherein, the first fluid layer is connected to the reaction layer through the diffusion layer, and the reaction layer and the heat exchange layer are not connected, the first fluid layer is provided with a first fluid inlet 6, and the reaction layer is provided with a second fluid inlet 7 and a product outlet 12 at both ends; the heat exchange layer is provided with a heat exchange medium inlet 8 and a heat exchange medium outlet 9 at both ends.

[0039] Preferably, the first fluid inlet 6 is further connected to at least one third fluid inlet 10; more preferably, multiple third fluid inlets 10 are connected to the first fluid inlet 6 via a mixer 5; the second fluid inlet 7 is further connected to at least one fourth fluid inlet 11, more preferably, multiple fourth fluid inlets 11 are connected to the second fluid inlet 7 via a mixer 5. Preferably, the mixer is selected from a jet mixer or a static mixer.

[0040] Preferably, the first fluid layer, reaction layer and heat exchange layer are sheet spaces, the diffusion layer is an open-pore structure, the first fluid layer sheet thickness h1 is 0.5cm-10cm, the diffusion layer sheet thickness h2 is 0.1cm-2cm, the reaction layer sheet thickness h3 is not greater than 3cm, and the heat exchange layer sheet thickness h4 is 0.5cm-3cm.

[0041] Preferably, the diffusion layer is a porous medium and / or a regular corrugated plate, preferably foam metal or sintered metal; the average pore size of the diffusion layer pores is 3 μm-500 μm, preferably 5-100 μm.

[0042] Preferably, the reaction layer is provided with a plurality of baffles, which are arranged in parallel or staggered to form baffle channels, and the width of the baffle channels is 0.1 cm to 1.5 cm. The baffles increase fluid disturbance and improve mixing quality.

[0043] Preferably, an internal component 15 is provided in the deflection channel 14, and the internal component has smooth notches in both the longitudinal and transverse sections. The longitudinal direction refers to the flow direction of the deflection channel, and the transverse direction refers to the direction perpendicular to the flow direction of the deflection channel, so that the cross-sectional area of ​​the deflection channel at the position of the internal component is reduced by 20%-80%.

[0044] Preferably, a rectifying and distributing plate is provided in the first fluid layer, and holes are opened on the rectifying and distributing plate.

[0045] The polymerization microreactor of this utility model can be used as an amplification unit, amplifying the processing capacity by stacking different units. A diffusion layer is provided in the polymerization microreactor, allowing the gaseous reactants to form uniform microbubbles within the dispersion layer and enter the reaction layer. Because the bubble size is smaller than the fluid channel size of the reaction layer, the pressure pulsation of the gas and liquid caused by bubble movement is reduced, thereby enhancing the uniformity of gas and liquid distribution during parallel amplification.

[0046] The microreactor provided by the present invention is suitable for multiphase fluid mixing reaction processes such as gas-liquid and gas-liquid-liquid, and is particularly suitable for exothermic reactions. The application method of the microreactor is illustrated using olefin polymerization as an example. Olefin enters the reaction layer of the microreactor through the second fluid inlet; the liquid catalyst entering through the first fluid inlet and the supplementary gas catalyst introduced through the third fluid inlet are pre-mixed in the mixer and then enter the first fluid layer. The catalyst mixture passes through the diffusion layer from the first fluid layer, is evenly dispersed, and then enters the reaction layer, where it contacts the olefin and catalyzes the olefin polymerization reaction. Since olefin polymerization is a highly exothermic reaction, the heat exchange medium enters the heat exchange layer through the heat exchange medium inlet and flows out through the heat exchange medium outlet, exchanging heat with the reactant flow in the reaction layer and promptly removing the heat of reaction.

[0047] In an olefin polymerization reaction, an olefin monomer is polymerized in the presence of a catalyst co-agent and a catalyst mixture to obtain an olefin polymer. The catalyst co-agent is an alcohol compound having 4 to 8 carbon atoms and / or an alkyl ester compound having 4 to 8 carbon atoms. The catalyst co-agent is used in an amount of 0.01 to 5.0% by weight based on the amount of the monomers used. The gas-phase catalyst is BF3, and the gas-phase catalyst is used in an amount of 0.01 to 5% by weight based on the amount of the monomers used.

[0048] The microreactor provided by the utility model is used for olefin polymerization reactions. The large contact surface between the reaction layer and the heat exchange layer prevents rapid temperature rise due to reaction exotherm and reduces the formation of dimer products due to localized temperature increases. Furthermore, in the microreactor provided by the utility model, the catalyst mixture is uniformly dispersed throughout the reaction layer from the first fluid layer through the diffusion layer. The presence of the diffusion layer ensures uniform distribution of the catalyst mixture within the reaction layer, improving olefin conversion and target product selectivity.

[0049] In one embodiment, the microreactor of the present invention is provided with baffles in the reaction layer, with multiple baffles arranged in parallel or staggered to form baffle channels. The baffles increase fluid disturbance and improve the mixing effect of reactants and catalysts.

[0050] In a preferred embodiment, a baffle is provided in the reaction layer, and a plurality of internal components are distributed in the baffle channel formed by the baffle, wherein the internal components are provided with semicircular, rectangular, triangular, trapezoidal or semi-elliptical channels with an equivalent diameter of less than 1 mm.

[0051] In a specific embodiment, the inner component is a structure with uneven thickness and a smooth surface. Along the direction of fluid advance, the thickness of the inner component first increases and then decreases. Along the radial direction from the side wall to the center, the thickness of the inner component first increases and then decreases, so that the cross-sectional area of ​​the deflection channel at the center position of the inner component is reduced to 20%-80%.

[0052] In a preferred embodiment, a rectifying and distributing plate is disposed within the first fluid layer, and the plate has openings therein. The plate has a thickness of 0.1 cm to 1 cm, and the openings therein may be multiple straight or curved channels that are distributed in parallel or staggered fashion. The rectifying and distributing plate can be positioned near the dispersion layer and closely fit the dispersion layer.

[0053] In the second aspect, the production device of polyalphaolefin base oil provided by the utility model includes a Fischer-Tropsch microreactor, a first distillation tower, a second distillation tower, a polymerization microreactor, a centrifugal separator and a third distillation tower connected in sequence, and the polymerization microreactor is any one of the above-mentioned microreactors; wherein, the side line discharge of the second distillation tower is connected to the second fluid inlet of the polymerization microreactor, the product outlet of the polymerization microreactor is connected to the centrifugal separator, and the light material outlet of the centrifugal separator is connected to the third distillation tower.

[0054] The polyalphaolefin base oil production device is used to produce polyalphaolefin base oil, wherein a Fischer-Tropsch microreactor is used for preparing alpha olefins by Fischer-Tropsch reaction of synthesis gas; a first distillation tower is used for separating a fraction with a carbon number of 8-12; a second distillation tower is used for separating an olefin mixture with a carbon number of 8-12; a polymerization microreactor is used for the polymerization reaction of alpha olefins to produce alpha olefin polymers; a centrifugal separator is used for separating liquid phases with different densities to obtain a liquid catalyst with a higher density, the separated liquid phase with a lower density flows out from a light material outlet, and the liquid phase with a higher density flows out from a heavy material outlet; and a third distillation tower is used for separating the alpha olefin polymer.

[0055] The present invention provides a polyalphaolefin base oil production apparatus, wherein a first distillation tower and a second distillation tower are each provided with an overhead discharge, a bottom discharge, and at least one side discharge for fractionating and cutting the Fischer-Tropsch synthesis product to obtain a C8-C12 olefin mixture. The side discharge of the first distillation tower is connected to the feed inlet of the second distillation tower, and the side discharge of the second distillation tower is connected to the fluid inlet of the polymerization reactor.

[0056] The centrifugal separator is provided with a light material outlet and a heavy material outlet. The heavy material outlet discharges a denser liquid catalyst. Preferably, the heavy material outlet of the centrifugal separator is connected to the first fluid inlet of the polymerization microreactor; the liquid catalyst separated by the centrifugal separator is returned to the polymerization microreactor for recycling.

[0057] Preferably, multiple groups of reaction channels and heat exchange channels are arranged in parallel in the Fischer-Tropsch microreactor, the two ends of the reaction channel are respectively connected to the synthesis gas inlet and the Fischer-Tropsch product outlet, and the two ends of the heat exchange channel are respectively connected to the heat exchange medium inlet and the heat exchange medium outlet; the heat exchange surface is between the reaction channel and the heat exchange channel, and in the vertical direction to the heat exchange surface, the layer height of the reaction channel and the heat exchange channel is respectively <1cm; preferably <3mm.

[0058] In the Fischer-Tropsch microreactor, a heat exchange internal component is provided in the heat exchange medium inlet, and the heat exchange internal component is a porous structure with a pore size of 3μm-5000μm, preferably 5-μm2000μm.

[0059] The apparatus provided in this utility model is used to produce polyalphaolefin base oil. The third distillation tower is used to separate lighter byproducts, target products, and heavier byproducts from the alpha olefin polymerization product. The third distillation tower is equipped with an overhead discharge, a side discharge, and a bottom discharge, respectively obtaining the lighter byproducts, target products, and heavier byproducts.

[0060] In a preferred embodiment, more than two heat exchange medium inlets are provided in the Fischer-Tropsch microreactor, and a heat exchange strengthening component is provided at the heat exchange medium inlet to change the initial flow direction of the heat exchange medium, so that the heat exchange medium is evenly distributed in the heat exchange channel, thereby solving the problem of uneven distribution of the heat exchange medium flow, thereby improving the heat transfer capacity of the reaction channel and improving product quality.

[0061] Preferably, the heat exchange strengthening component is provided with holes or slits, preferably made of foam metal or sintered metal. The opening size of the heat exchange strengthening component is 3 μm-5000 μm, more preferably 5-2000 μm.

[0062] The present invention provides an application method for a polyalphaolefin base oil production device. Synthesis gas is introduced into a Fischer-Tropsch microreactor for a Fischer-Tropsch reaction to obtain a crude Fischer-Tropsch product. The crude Fischer-Tropsch product is fractionated in a first distillation tower to obtain a C8-C12 alkane-olefin mixture. The C8-C12 alkane-olefin mixture is further fractionated in a second distillation tower to obtain a C8-C12 olefin mixture. A catalytic promoter, a supplementary gas catalyst, and a recycled catalyst are separately introduced into a mixer for premixing, and then introduced into a polymerization microreactor for olefin polymerization. The crude polymerization product passes through a centrifugal separator to separate the catalytic promoter and gas catalyst mixture, which is then returned to the polymerization microreactor via a catalyst recycling channel. The remaining solution is further distilled into a third distillation tower to obtain a base oil product.

[0063] The polyalphaolefin base oil production device provided by the utility model realizes the continuous flow production of polyalphaolefin base oil from synthesis gas via the Fischer-Tropsch reaction. The polyalphaolefin base oil production device utilizes a Fischer-Tropsch microreactor and a polymerization microreactor. The microreactor system has a compact architecture and a small footprint, saving significant upfront investment and reducing operating costs. The microreactor system also has a low liquid storage volume, reducing safety risks. The structure and form of the two microreactors facilitate scale-up, provide excellent mixing effects, and offer high heat exchange efficiency and selectivity for the target product.

[0064] During the synthesis of polyalphaolefin base oil, the substance with catalytic activity is a complex formed by the reaction of a catalytic promoter and a gas catalyst. By setting a catalyst recycling channel, a catalytic promoter inlet channel, a supplementary gas catalyst inlet channel and a premixing device in the polymerization microreactor, the recycled catalyst mixture and the supplementary catalyst are fully mixed, and the formation of catalytically active substances is precisely controlled.

[0065] The structure and application method of the microreactor and polyalphaolefin base oil production device provided by the present invention are described below with reference to the figures, but the present invention is not limited thereto.

[0066] Figure 1 This is a schematic diagram of the structure of the microreactor provided by the utility model. Figure 1 As shown, the microreactor includes a first fluid layer 1, a diffusion layer 2, a reaction layer 3, and a heat exchange layer 4, which are arranged adjacent to each other in sequence. The first fluid layer 1 communicates with the reaction layer 3 through the diffusion layer 2, while the reaction layer 3 is not connected to the heat exchange layer 4. The first fluid layer 1 is provided with a first fluid inlet 6, and the reaction layer 3 is provided with a second fluid inlet 7 and a product outlet 12 at both ends. The heat exchange layer 4 is provided with a heat exchange medium inlet 8 and a heat exchange medium outlet 9 at both ends. The second fluid inlet 7 is also connected to the outlet of the mixer 5, and the two fourth fluid inlets are connected to the inlet of the mixer 5.

[0067] Figure 2 FIG. 1 is a schematic diagram of the structure of the reaction layer in one embodiment of a microreactor. Figure 2 As shown, in the reaction layer 3, a plurality of baffles 13 are arranged in parallel to form a tortuous baffle channel 14, which increases fluid disturbance and improves mixing effect.

[0068] Figure 3 Schematic diagram of the structure of the reaction layer in the second embodiment of the microreactor. Figure 4 Schematic diagram of the internal components in the second embodiment of the microreactor at the aa section and the bb section. Figure 3 、 Figure 4 As shown, multiple baffles 13 are arranged in parallel in the reaction layer 3 to form a tortuous baffle channel 14. Multiple internal components 15 are evenly distributed in the baffle channel 14. The internal components 15 have smooth notches in both the longitudinal section aa and the transverse section bb, which reduces the cross-sectional area of ​​the baffle channel at the location of the internal components by 20%-80%. The longitudinal direction refers to the flow direction of the baffle channel, and the transverse direction refers to the direction perpendicular to the flow direction of the baffle channel.

[0069] Figure 5 The schematic diagram of the production process of the polyalphaolefin base oil provided by the utility model. Figure 5 As shown, the polyalphaolefin base oil production device includes a Fischer-Tropsch microreactor 20, a first distillation tower 21, a second distillation tower 22, a polymerization microreactor 23, a centrifugal separator 24 and a third distillation tower 25, which are sequentially connected. Synthesis gas enters the Fischer-Tropsch microreactor through the synthesis gas inlet 26. The Fischer-Tropsch crude product 28 obtained after the reaction enters the first distillation tower 21 for fractionation to obtain a C8-C12 hydrocarbon fraction. The fraction enters the second distillation tower 22 for further fractionation to obtain a C8-C12 olefin fraction. The fraction enters the reaction layer of the polymerization microreactor 13. The liquid catalyst and the catalyst mixture pre-mixed in the mixer with the supplementary gas catalyst enter the first fluid layer, pass through the diffusion layer and enter the reaction layer. The olefins contact the catalyst mixture to undergo polymerization reaction. The obtained post-polymerization stream 30 enters the centrifugal separator 24 to separate the polymerization product 32 and the liquid-phase catalyst according to different densities. The separated liquid-phase catalyst is returned to the polymerization reactor for recycling through the catalyst circulation line 31. The separated polymerization product enters the third distillation tower 25 for further separation into the target product 34 and the by-product 33.

[0070] The polymerization microreactor 23 can be used as a unit, and the processing volume can be amplified by stacking multiple units.

[0071] Figure 6 This is a top view of the central section of the Fischer-Tropsch microreactor. Figure 7 This is a side view of the central section of the Fischer-Tropsch microreactor. Figure 6 、 Figure 7As shown, the Fischer-Tropsch microreactor includes a cross-linked reaction channel 105 and a heat exchange channel 103, as well as a synthesis gas inlet 26, a product outlet 27, a Fischer-Tropsch heat exchange medium inlet channel 101, and a Fischer-Tropsch heat exchange medium outlet channel 104. A Fischer-Tropsch heat exchange enhancement member 102 is provided downstream of the heat exchange medium inlet channel 101.

[0072] The structure and technical effects of the microreactor provided by the present invention will be described below through examples, but the present invention is not limited thereto.

[0073] Comparative Example 1

[0074] 1-decene is used as the polymerization raw material for alpha olefin polymerization, the catalytic aid is 1-butanol, and the catalyst is BF3.

[0075] Purge the reactor with nitrogen. Add 20 mL of 1-decene to a stainless steel stirred tank reactor, then dropwise add 0.2 mL of n-butanol. BF₃ gas is introduced until bubbling forms at the liquid surface. The reaction is maintained at 40°C for 4 h, with the pressure maintained at 0.4 MPa, and then terminated.

[0076] The conversion rate and product distribution of the reaction are shown in Table 1.

[0077] The concentration of olefins in the product was analyzed by off-line chromatography and measured using Agilent's GC6890-SCD instrument.

[0078] Cool the raw material to room temperature and transfer it to a separatory funnel. Add NaOH solution and a small amount of distilled water, shake well, and let it stand. Once an aqueous layer has separated, check the pH of the aqueous layer with pH test paper. Repeat this process until the pH of the aqueous layer reaches 7. Let it stand for a while. Once all the water has separated, separate the solution and directly perform liquid chromatography analysis to determine the 1-decene concentration in the raw material.

[0079] Cool the product to room temperature and transfer it to a separatory funnel. Add NaOH solution and a small amount of distilled water, shake well, and let it sit. Once an aqueous layer has separated, test the pH of the aqueous layer with pH test paper. Repeat this process until the pH of the aqueous layer reaches 7. Let it sit for a while. Once all the water has separated, separate the product and directly perform liquid chromatography analysis to measure the concentrations of monomer, dimer, trimer, and tetramer in the product.

[0080] Calculation: Conversion rate of raw materials = 1 - 1-decene concentration in product / 1-decene concentration in raw materials.

[0081] The selectivity of each product (N-mer) = the concentration of N-mer in the product / the conversion rate of the raw material.

[0082] Example 1

[0083] The technical effect of the microreactor provided by the utility model is illustrated by the α-olefin polymerization process. Figure 1 The microreactor shown performs the synthesis of polyalphaolefin base oils.

[0084] The inlet channel for the supplementary gas catalyst adopts Ф2 stainless steel pipe, and other pipes adopt Ф6 stainless steel pipe. The premixing equipment adopts a small stirring kettle with a diameter of 100mm, and the blade adopts a six-straight blade inclined blade with a blade diameter of 60mm. The cross-section of the main structure of the polymerization reactor is 200mm*200mm square, the thickness of the rectifying distribution layer is 10mm, and 20 parallel channels are set on the rectifying distribution plate with a channel width of 5mm. The diffusion layer is made of foam metal with a pore size of 30μm and a diffusion layer thickness of 0.5mm. The reaction layer is 2mm thick, and a baffle is set inside with a spacing of 10mm. BF3, 1-decene, 1-butanol and the recovered catalyst mixture are respectively Figure 3 The supplementary gas enters the reactor through the catalyst inlet channel, the olefin channel, the catalyst auxiliary inlet channel and the catalyst mixture recycling channel to undergo polymerization reaction, and the obtained reaction product is drawn out from the polymerization crude product channel.

[0085] The reaction temperature in the experimental method was essentially the same as in Comparative Example 1, and the reaction pressure was 2.5 MPa. In this example, the feed rates for 1-decene, n-butanol, and BF3 were 10 mL / min, 0.08 mL / min, and 32 mL / min, respectively. The catalyst was recovered and separated at 8 mL / min. Ten minutes after the start of the reactant feed, a stable product was obtained. The product properties are shown in Table 1.

[0086] Table 1

[0087] Comparative Example 1 Example 1 Conversion rate (%) 90.35 91.2 Dimer selectivity, wt% 13.37 5.35 Trimer selectivity (%) 32.57 43.21 Tetramer selectivity (%) 24.69 34.52 Pentamer selectivity (%) 15.03 13.18 > Pentamer selectivity (%) 3.84 3.74

[0088] The results in Table 1 show that, compared to conventional batch reactors, the present invention achieves higher feedstock conversion rates and significantly better selectivity for trimers and tetramers in the product than batch reactor technology. Furthermore, the present invention enables continuous flow production of PAO.

[0089] Comparative Example 2

[0090] Use Figure 2The Fischer-Tropsch microreactor shown. A single reaction channel is a linear channel, 1800 mm long and 10 mm*1 mm in cross section. Every 85 channels form a flat layer, and a total of 25 flat layers make up the entire reaction channel. A heat exchange layer is set between each reaction flat layer. In the heat exchange layer, the structure and arrangement of each heat exchange channel are consistent with those of each reaction layer. The difference is that the channels in the reaction layer and the heat exchange layer are arranged vertically and crosswise. The Fischer-Tropsch heat exchange medium distribution chamber is hemispherical. The heat exchange medium is deionized water. The Fischer-Tropsch heat exchange medium distribution chamber is only connected to two heat exchange fluid inlets. The Fischer-Tropsch heat exchange medium collection chamber is only connected to one heat exchange fluid outlet. The standard deviation value of the heat exchange fluid distribution in each channel is measured when the total flow rate of different heat exchange media is different. The test results are shown in Table 2.

[0091] Example 2

[0092] The Fischer-Tropsch microreactor described in Comparative Example 1 was used, except that the Fischer-Tropsch heat exchange medium was divided into three inlet channels connected to the heat exchange medium distribution chamber. A Fischer-Tropsch heat exchange reinforcement member was placed downstream of each of the three inlet channels. This reinforcement member was a cylindrical material with sieve holes and an average pore diameter of 30 μm. The uniformity of the heat exchange fluid distribution was determined by measuring the standard deviation of the heat exchange fluid distribution within each channel at different total heat exchange medium flow rates. The test results are shown in Table 2.

[0093] Table 2

[0094]

[0095] As can be seen from Table 2, the technology adopted in the present invention can significantly improve the distribution effect of the heat exchange medium in each channel of the Fischer-Tropsch microreactor, so that the local heat generated in the reaction channel can be removed in time, thereby improving the product conversion rate and selectivity.

Claims

1. A microreactor, characterized in that The invention comprises a first fluid layer (1), a diffusion layer (2), a reaction layer (3) and a heat exchange layer (4) which are arranged in sequence; wherein the first fluid layer is connected to the reaction layer through the diffusion layer, and the reaction layer and the heat exchange layer are not connected; the first fluid layer is provided with a first fluid inlet (6); the reaction layer is provided with a second fluid inlet (7) and a product outlet (12) at both ends; and the heat exchange layer is provided with a heat exchange medium inlet (8) and a heat exchange medium outlet (9) at both ends.

2. The microreactor according to claim 1, characterized in that The first fluid inlet (6) is also connected to at least one third fluid inlet (10), and the second fluid inlet (7) is also connected to at least one fourth fluid inlet (11).

3. The microreactor according to claim 2, characterized in that The plurality of third fluid inlets are connected to the first fluid inlet via the mixer.

4. The microreactor according to claim 2, characterized in that The plurality of fourth fluid inlets are connected to the second fluid inlet via the mixer.

5. The microreactor according to claim 3 or 4, characterized in that The mixer is selected from a jet mixer or a static mixer.

6. A microreactor according to any one of claims 1 to 4, characterized in that The first fluid layer, reaction layer and heat exchange layer are sheet spaces, the diffusion layer is an open-pore structure, the first fluid layer sheet thickness h1 is 0.5cm-10cm, the diffusion layer sheet thickness h2 is 0.1cm-2cm, the reaction layer sheet thickness h3 is not greater than 3cm, and the heat exchange layer sheet thickness h4 is 0.5cm-3cm.

7. The microreactor according to claim 6, characterized in that The diffusion layer is selected from a porous medium structure and / or a regular corrugated plate, and the average pore size of the pores in the diffusion layer is 3 μm-500 μm.

8. The microreactor according to claim 7, characterized in that The diffusion layer is made of foam metal or sintered metal, and the average pore size of the diffusion layer pores is 5-100 μm.

9. The microreactor according to any one of claims 1 to 4, characterized in that A plurality of baffles (13) are provided in the reaction layer, and the baffles are arranged in parallel or staggered to form baffle channels (14). The width of the baffle channels is 0.1 cm-1.5 cm.

10. The microreactor according to claim 9, characterized in that An internal component (15) is provided in the deflection channel, and the internal component has smooth notches in both the longitudinal and transverse sections. The longitudinal direction refers to the flow direction of the deflection channel, and the transverse direction refers to the direction perpendicular to the flow direction of the deflection channel, so that the cross-sectional area of ​​the deflection channel at the position of the internal component is reduced by 20%-80%.

11. The microreactor according to any one of claims 1 to 4, characterized in that A rectifying and distributing plate is provided in the first fluid layer, and holes are opened on the rectifying and distributing plate.

12. A production device for polyalphaolefin base oil, characterized in that: The method comprises a Fischer-Tropsch microreactor, a first distillation tower, a second distillation tower, a polymerization microreactor, a centrifugal separator and a third distillation tower connected in sequence, wherein the polymerization microreactor is the microreactor described in any one of claims 1 to 11; wherein the side discharge of the second distillation tower is connected to the second fluid inlet of the polymerization microreactor, the product outlet of the polymerization microreactor is connected to the centrifugal separator, and the light material outlet of the centrifugal separator is connected to the third distillation tower.

13. The production device of polyalphaolefin base oil according to claim 12, characterized in that: The heavy material outlet of the centrifugal separator is connected to the first fluid inlet of the polymerization microreactor.

14. The production device of polyalphaolefin base oil according to claim 12, characterized in that: Multiple groups of reaction channels and heat exchange channels are arranged in parallel in the Fischer-Tropsch microreactor, the two ends of the reaction channel are respectively connected to the synthesis gas inlet and the Fischer-Tropsch product outlet, and the two ends of the heat exchange channel are respectively connected to the heat exchange medium inlet and the heat exchange medium outlet; the heat exchange surface is between the reaction channel and the heat exchange channel, and in the vertical direction to the heat exchange surface, the layer height of the reaction channel and the heat exchange channel is <1 cm.

15. The production device of polyalphaolefin base oil according to claim 14, characterized in that: In the direction perpendicular to the heat exchange surface, the layer heights of the reaction channel and the heat exchange channel are respectively less than 3 mm.

16. The production device of polyalphaolefin base oil according to claim 14 or 15, characterized in that: In the Fischer-Tropsch microreactor, a heat exchange internal component is provided in the heat exchange medium inlet, and the heat exchange internal component is a porous structure with a pore size of 3μm-5000μm.

17. The production device of polyalphaolefin base oil according to claim 16, characterized in that: The pore size of the porous structure is 5 μm-2000 μm.

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