Ethoxyquin clean production process using SMBR

Abstract

The application discloses a kind of ethoxyquin clean production process using SMBR, comprising: preparation of adsorbent filled with catalytic effect dual-purpose reactor of simulated moving bed chromatographic separation system;Preparation mixture, consisting of acetone and p-amino phenetol;Preparation eluent;The mixture is continuously injected into simulated moving bed chromatographic separation system, and eluent is injected simultaneously, under the catalytic effect of adsorbent, condensation reaction occurs between acetone and p-amino phenetol to generate ethoxyquin and water, and chromatographic separation is carried out simultaneously, and the eluent solution component of ethoxyquin and the eluent solution component of water are collected.The application obtains high-purity ethoxyquin under the premise of not using water-containing agent, without water washing and alkali washing, realizes efficient and sufficient use of reaction raw materials, completely eliminates the generation of high-salt high-COD wastewater, and improves the conversion rate of raw materials, the yield of product and the purity of product to more than 98%, reaching the international advanced level.

Description

Technical Field

[0001] This invention belongs to the field of organic preparation technology, specifically relating to a clean production process of ethoxyquinoline using SMBR. Background Technology

[0002] Currently, the production of ethoxyquinoline (6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline) mainly adopts the principle of "acidic catalyst-catalyzed condensation and dehydration reaction of p-aminophenethyl ether with acetone". The synthesis reaction process can be represented as follows:

[0003]

[0004] The production process basically follows the intermittent batch production process.

[0005] Chinese patent CN107098854A discloses a continuous production method for ethoxyquinoline. The method involves adding liquid p-aminophenethyl ether, an acidic catalyst p-toluenesulfonic acid, and half of the liquid solvent (toluene) used for dehydration, to the top of a tower reactor via a mixing vessel. Inside the tower reactor, the mixture reacts with a mixture of acetone vapor and the other half of the solvent (toluene) used for azeotropic dehydration. The condensation product is continuously discharged from the bottom of the tower and sent to a "water washing and neutralization process." The resulting mixture of water, toluene azeotropic vapor, and some unreacted acetone vapor is continuously discharged from the reactor and condensed into a liquid, continuously separated into a toluene phase and an aqueous phase. The toluene is returned to the system for reuse, and the aqueous solution containing some acetone is sent to a "distillation and purification process" to recover acetone. This method uses a tower reactor to allow the reaction to proceed continuously, thus improving reaction efficiency and shortening reaction time. However, because a solid catalyst is not used to fill the tower, the reaction mixture flowing from the bottom of the tower is essentially unchanged from the reaction mixture obtained in intermittent batch production. Both require large amounts of water and alkaline water for washing to obtain a qualified ethoxyquinoline product. This method still generates a large amount of difficult-to-treat high-salt, high-COD wastewater, and the process still needs to be improved to meet the requirements of environmentally friendly clean production. Summary of the Invention

[0006] The purpose of this invention is to provide a clean production process for ethoxyquinoline that can achieve continuous and stable production, eliminate the need for water washing and alkali washing processes, and achieve zero discharge of high-salt and high-COD wastewater.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] A clean production process for ethoxyquinoline using SMBR includes the following steps:

[0009] Step (1): Prepare a simulated moving bed chromatography separation system (SMBR) filled with an adsorbent that also serves as a reactor and has catalytic activity;

[0010] Step (2): Prepare a mixture consisting of (i) acetone and (ii) p-aminophenethyl ether;

[0011] Step (3): Prepare the eluent;

[0012] Step (4): The mixture is continuously injected into the simulated moving bed chromatography separation system, and the eluent is injected simultaneously. Under the catalysis of the adsorbent, acetone and p-aminophenethyl ether undergo a condensation reaction to generate ethoxyquinoline and water, and chromatographic separation is carried out simultaneously. The eluent solution components of ethoxyquinoline and water are collected.

[0013] Step (5): The eluent solution components of the water are dehydrated, and the dehydrated eluent is returned to the SMBR for recycling.

[0014] Step (6): Remove the eluent from the eluent solution component of ethoxyquinoline to obtain the ethoxyquinoline product; recover the eluent and return it to the SMBR for recycling.

[0015] The simulated moving bed chromatography system consists of 12 to 36 chromatography columns packed with adsorbent that also serves as a catalyst, connected end to end. Each column has two inlets and two outlets, with one inlet (I...) 混 One inlet is used for feeding the mixture as reactants, and the other inlet (I) is used for feeding the mixture as reactants. 洗 ) is used for eluent feeding, with one outlet (O) 产品 The other outlet (O) is used to discharge the eluent solution components of ethoxyquinoline. 水 The eluent solution components used to drain the water are controlled by solenoid valves at each inlet and outlet.

[0016] Specifically, the simulated moving bed chromatography separation system consists of 24 chromatography columns connected end to end, each filled with an adsorbent that also has catalytic activity.

[0017] Specifically, the feed inlet (I) of the 9th column in the simulated moving bed chromatography separation system. 混9 The mixture is continuously injected into the simulated moving bed chromatography system, from the feed inlet (I) of the first column of the simulated moving bed chromatography system. 洗1 The eluent is continuously injected into the simulated moving bed chromatography system, and the eluent is discharged from the outlet (O) of the 24th column. 酯24 The eluent solution fraction of ethoxyquinoline was discharged at the outlet of the 5th chromatography column (O). 水5The eluent solution component of the discharged water is switched to the feed port of the mixture of the next chromatography column, the feed port of the eluent of the next chromatography column, the discharge port of the water eluent solution component of the next chromatography column, and the discharge port of the ethoxyquinoline eluent solution component of the next chromatography column, respectively, according to the stepping speed.

[0018] The stepping speed is 5 to 10 minutes.

[0019] The adsorbent with catalytic activity can be at least one of immobilized p-toluenesulfonic acid, immobilized methanesulfonic acid, ion exchange resin or solid superacid, or a mixture of at least one of immobilized p-toluenesulfonic acid, immobilized methanesulfonic acid, ion exchange resin or solid superacid and at least one of activated carbon, diatomaceous earth, activated clay, silica gel, polyacrylamide, alumina.

[0020] Preferably, the adsorbent with catalytic activity is a combination of silica gel, solid superacid, and strong acid cation exchange resin in a mass ratio of 0.1:(0.1-0.3):(6-10).

[0021] Preferably, the adsorbent with catalytic activity is a combination of silica gel, solid superacid, and strong acid cation exchange resin in a mass ratio of 0.1:0.1:9.

[0022] The immobilized p-toluenesulfonic acid is prepared by the following method: while stirring, a mixed aqueous solution of sodium alginate, polyvinyl alcohol, and p-toluenesulfonic acid is added dropwise to a calcium chloride solution to obtain a granular gel. This gel is filtered, air-dried naturally, and then placed in an oven at 60°C overnight to obtain immobilized p-toluenesulfonic acid. The mass ratio of sodium alginate, polyvinyl alcohol, and p-toluenesulfonic acid is (3-6):(6-12):(1-40), specifically 5:10:35. In the mixed aqueous solution of sodium alginate, polyvinyl alcohol, and p-toluenesulfonic acid, the mass percentage of sodium alginate is generally 3-6%, specifically 5%. The mass percentage of the calcium chloride solution is 3-8%, specifically 5%. The volume ratio of the mixed aqueous solution of sodium alginate, polyvinyl alcohol, and p-toluenesulfonic acid to the calcium chloride solution is 1:1 to 1:3.

[0023] The immobilized methanesulfonic acid is prepared by the following method: while stirring, a mixed aqueous solution of sodium alginate, polyvinyl alcohol, and methanesulfonic acid is added dropwise to a calcium chloride solution to obtain a granular gel. This gel is filtered, air-dried naturally, and then placed in an oven at 60°C overnight to obtain immobilized methanesulfonic acid. The mass ratio of sodium alginate, polyvinyl alcohol, and methanesulfonic acid is (3-6):(6-12):(1-40), specifically 5:10:40. In the mixed aqueous solution of sodium alginate, polyvinyl alcohol, and methanesulfonic acid, the mass percentage of sodium alginate is generally 3-6%, specifically 5%. The mass percentage of the calcium chloride solution is 3-8%, specifically 5%. The volume ratio of the mixed aqueous solution of sodium alginate, polyvinyl alcohol, and methanesulfonic acid to the calcium chloride solution is 1:1 to 1:3.

[0024] The ion exchange resin is a 732 hydrogen-type strong acid cation exchange resin.

[0025] The solid superacid is prepared by the following method: Zr(OH)4 is impregnated in concentrated sulfuric acid overnight, and then calcined at 500-650°C for 5 hours in air to obtain the solid superacid.

[0026] The concentration of the concentrated sulfuric acid is 96%.

[0027] In the mixture, the molar ratio of acetone to p-aminophenethyl ether is greater than the theoretical molar ratio, i.e., >2:1.

[0028] The eluent is acetone, or a mixed solvent of toluene and acetone in a volume ratio of 0:100 to 100:0.

[0029] In the SMBR described above, the condensation reaction and simultaneous chromatographic separation are carried out at a temperature of 80–200°C and a pressure of 1–3 MPa, preferably at a temperature of 120–160°C and a pressure of 1–1.5 MPa.

[0030] The beneficial effects of this invention are:

[0031] In a simulated moving bed chromatography system filled with an adsorbent that also functions as a reactor, p-aminophenethyl ether and acetone undergo a condensation reaction under the catalysis of the adsorbent to produce ethoxyquinoline and water. Simultaneously, SMBR chromatography is performed to separate the ethoxyquinoline and water eluent solutions, collecting the eluent solution components of both. This allows for the high-conversion and high-purity ethoxyquinoline without the use of dehydrating agents, water washing, or alkali washing. This achieves efficient and full utilization of the reaction raw materials, completely eliminating the generation of high-salt, high-COD wastewater. The conversion rate of the raw materials, the yield of the product, and the purity of the product are all increased to over 98%, reaching the international advanced level.

[0032] Ethoxyquinoline products are bright yellow in color, of excellent quality, with significantly reduced production costs, a substantial decrease in solid waste generation, and a significant improvement in the environmental friendliness of the process. Detailed Implementation

[0033] The technical solution of the present invention will be further described below with reference to the embodiments.

[0034] A clean production process for ethoxyquinoline using SMBR includes the following steps:

[0035] Step (1): Prepare a simulated moving bed chromatography separation system (SMBR) filled with an adsorbent that also serves as a reactor and has catalytic activity;

[0036] Step (2): Prepare a mixture consisting of (i) acetone and (ii) p-aminophenethyl ether;

[0037] Step (3): Prepare the eluent;

[0038] Step (4): The mixture is continuously injected into the simulated moving bed chromatography separation system, and the eluent is injected simultaneously. Acetone and p-aminophen ether undergo a condensation reaction under the catalysis of the adsorbent to generate ethoxyquinoline and water, and chromatographic separation is performed simultaneously. The eluent solution components of ethoxyquinoline and water are collected respectively.

[0039] Step (5): The eluent solution components of the water are dehydrated, and the dehydrated eluent is returned to the SMBR for recycling.

[0040] Step (6): Remove the eluent from the eluent solution component of ethoxyquinoline to obtain the ethoxyquinoline product; recover the eluent and return it to the SMBR for recycling.

[0041] The adsorbent with catalytic activity can be at least one of immobilized p-toluenesulfonic acid, immobilized methanesulfonic acid, and ion exchange resin, or a mixture of at least one of immobilized p-toluenesulfonic acid, immobilized methanesulfonic acid, ion exchange resin, or solid superacid with at least one of activated carbon, diatomaceous earth, activated clay, silica gel, polyacrylamide, and alumina.

[0042] The eluent can be acetone or a mixed solvent of toluene and acetone in a volume ratio of 0:100 to 100:0.

[0043] In the SMBR described above, the condensation reaction and simultaneous chromatographic separation are carried out at a temperature of 80–200°C and a pressure of 1–3 MPa, preferably at a temperature of 120–160°C and a pressure of 1–1.5 MPa.

[0044] Example 1

[0045] This embodiment utilizes an SMBR system for the clean production of ethoxyquinoline. The system comprises a simulated moving bed chromatography (SMBR) system with 24 chromatography columns (φ800×2000 mm) connected in series. The last column (the 24th column) is connected to the first column (the 1st column), forming a connected simulated moving bed chromatography system. Each column is filled with a mixture of silica gel, solid superacid, and strong acid cation exchange resin in a mass ratio of 0.1:0.1:9 as an adsorbent with catalytic activity. Each column has two inlets and two outlets, one of which is a feed inlet (I...). 混n n is an integer from 1 to 24, and the feed inlet of the reaction mixture for the first chromatography column is I. 混1 The feed inlet for the reaction mixture of the second chromatography column is I. 混2 Similarly, the feed inlet for the mixture of reaction raw materials in the 24th chromatography column is I. 混24 One inlet is used for feeding the mixture of reactants, and the other inlet is (I). 洗n n is an integer from 1 to 24, and the eluent inlet of the first chromatography column is I. 洗1 The eluent inlet for the second chromatography column is I. 洗2 And so on, the eluent inlet for the 24th chromatography column is I. 洗24 ) for eluent feed, one outlet (O) 产品n n is an integer from 1 to 24, and the eluent solution component of the first chromatography column is discharged from port O. 产品1 The eluent solution component of ethoxyquinoline from the second chromatography column exits at port O. 产品2 Similarly, the eluent solution component of ethoxyquinoline in the 24th chromatography column exits at port O. 产品24 The other outlet (O) is used to discharge the eluent solution components of ethoxyquinoline. 水n n is an integer from 1 to 24, and the outlet of the water eluent solution component of the first chromatography column is O. 水1 The eluent solution component of the water in the second chromatography column exits at port O. 水2 Similarly, the outlet of the water eluent solution component of the 24th chromatography column is O. 水24 The eluent solution components used to drain water are controlled by solenoid valves at each inlet and outlet, opening and closing according to a preset program and step speed; one φ800×10000 acetone distillation column is used to dehydrate the water eluent solution components to obtain acetone; two φ1200×2500 desolvation kettles, one in use and one on standby, are used to remove the eluent from the ethoxyquinoline eluent solution components to obtain the ethoxyquinoline product; four 5m... 3Ingredient mixing tank.

[0046] The silica gel is for chromatography (product code: SGB-01, mesh size: 60-100 mesh).

[0047] Solid superacid is prepared by the following method: Zr(OH)4 is impregnated in 96% concentrated sulfuric acid overnight, and then calcined at 580-600℃ for 5 hours in air to obtain solid superacid.

[0048] The strong acid cation exchange resin is a 732 hydrogen type strong acid cation exchange resin.

[0049] The SMBR operates at a temperature of 140°C and a pressure of 1 MPa. A mixture of acetone (350 kg / h) and p-aminophenethyl ether (274 kg / h) is introduced from the feed inlet (I) of the reaction mixture on the 9th chromatography column. 混9 ) is continuously injected into the SMBR, where acetone and p-aminophenethyl ether undergo a condensation reaction under the catalysis of the adsorbent to produce ethoxyquinoline and water. Simultaneously, acetone (1000 kg / h) is introduced from the eluent inlet (I) of the first chromatography column. 洗1 ) is continuously injected into the SMBR as eluent, and chromatographic separation is performed simultaneously. The discharge port (O) of the 5th column is opened. 水5 (Flow rate set to 500 kg / h) Discharge the eluent solution components from the water, collect the eluent solution components from the water, and open the discharge port (O) of the 24th chromatography column. 产品24 (In valve fully open mode, flow uncontrolled) discharges the eluent solution component of ethoxyquinoline, collects the eluent solution component of ethoxyquinoline, and steps at a rate of switching every 10 minutes, switching to the inlet of the reaction mixture of the next chromatography column, the inlet of the eluent of the next chromatography column, the outlet of the water eluent solution component of the next chromatography column, and the outlet of the ethoxyquinoline eluent solution component of the next chromatography column, i.e., from I... 洗1 O 水5 I 混9 O 产品24 Switch to I 洗2 O 水6 I 混10 O 产品1 , by I 洗2 O 水6 I 混10 O 产品1 Switch to I 洗3 O 水7 I 混11 O 产品2 , by I 洗3 O 水7 I 混11 O 产品2 Switch to I 洗4 O水 8I 混12 O 产品3 The process continues in this manner; the water-based eluent solution component undergoes dehydration treatment, and the dehydrated acetone is returned to the SMBR for recycling; the acetone in the eluent solution component for removing ethoxyquinoline is used to obtain the ethoxyquinoline product; the acetone is recovered, returned to the SMBR, and recycled.

[0050] It can produce 5,000 tons of ethoxyquin with a purity of over 98% annually.

Claims

1. A process for the clean production of ethoxyquin using an SMBR, characterized in that: Includes the following steps: Step (1): Prepare a simulated moving bed chromatography separation system that also serves as a reactor, filled with an adsorbent that has catalytic activity. The simulated moving bed chromatography separation system consists of 12 to 36 chromatography columns filled with an adsorbent that has catalytic activity, connected end to end. The adsorbent that has catalytic activity is a combination of silica gel, solid superacid, and strong acid cation exchange resin in a mass ratio of 0.1:(0.1 to 0.3):(6 to 10). The strong acid ion exchange resin is 732 hydrogen-type strong acid cation exchange resin. The solid superacid is prepared by the following method: Zr(OH)4 is impregnated in concentrated sulfuric acid overnight and calcined at 500 to 650°C for 5 h in an air atmosphere to obtain the solid superacid. Step (2): Prepare a mixture consisting of acetone and p-aminophenethyl ether; Step (3): Prepare the eluent, wherein the eluent is acetone; Step (4): The mixture is continuously injected into the simulated moving bed chromatography separation system, and the eluent is injected simultaneously. Under the catalysis of the adsorbent, acetone and p-aminophen ether undergo a condensation reaction to generate ethoxyquinoline and water, and chromatographic separation is carried out simultaneously. The condensation reaction and simultaneous chromatographic separation are carried out at a temperature of 80-200℃ and a pressure of 1-3 MPa. The eluent solution components of ethoxyquinoline and water are collected. Step (5): The eluent solution components of water are dehydrated, and the dehydrated eluent is returned to the simulated moving bed chromatography separation system for recycling. Step (6): Remove the eluent from the eluent solution components of ethoxyquinoline to obtain the ethoxyquinoline product; recover the eluent and return it to the simulated moving bed chromatography separation system for recycling.

2. The ethoxyquin clean production process using SMBR according to claim 1, characterized in that: The adsorbent with catalytic activity is a combination of silica gel, solid superacid, and strong acid cation exchange resin in a mass ratio of 0.1:0.1:

9.

3. The ethoxyquin clean production process using SMBR according to claim 1, characterized in that: In the SMBR described above, the condensation reaction and simultaneous chromatographic separation are carried out at a temperature of 120–160 °C and a pressure of 1–1.5 MPa.

Images