CN-121988229-A - Reaction system and method for continuously preparing naphthenic amine hardener

CN121988229ACN 121988229 ACN121988229 ACN 121988229ACN-121988229-A

Abstract

The invention relates to a reaction system and a method for continuously preparing a naphthenic amine-based hardener. The system comprises a micro-channel reactor module, a slurry feeding unit and a hydrogen supply unit. The slurry feeding unit is used for providing slurry to the micro-channel reactor module. The slurry comprises a feedstock, a solvent, a catalyst, and the feedstock is 4,4' -diaminodiphenylmethane (MDA). The hydrogen supply unit is configured to supply hydrogen to the microchannel reactor module to be in gas-liquid contact with the slurry and to perform a hydrogenation reaction to form a product comprising 4,4' -diamino-dicyclohexylmethane (PACM).

Inventors

YUAN JINGYAO
CHEN ZHONGYU
WU RONGZU

Assignees

南亚塑胶工业股份有限公司

Dates

Publication Date: 20260508
Application Date: 20241111
Priority Date: 20241107

Claims (12)

1. A reaction system for the continuous preparation of a cycloalkane-based amine hardener, the reaction system comprising: A microchannel reactor module; A slurry feeding unit for providing a slurry to the microchannel reactor module, wherein the slurry comprises a feedstock, a solvent, and a catalyst, and the feedstock is 4,4' -diaminodiphenylmethane, and A hydrogen supply unit for supplying hydrogen to the microchannel reactor module for gas-liquid contact with the slurry and hydrogenation reaction to form a product comprising 4,4' -diamino-dicyclohexylmethane.
2. The reaction system for the continuous production of a cycloalkane-based amine hardener of claim 1, wherein the microchannel reactor module further comprises: A first micro-channel unit for receiving the slurry provided by the slurry feeding unit, preheating the slurry from a first temperature of feeding to a second temperature, wherein the first temperature is room temperature and the second temperature is 50-200 ℃, and A second microchannel unit connected in series with the rear side of the first microchannel unit for receiving the slurry having the second temperature, and maintaining the slurry at the second temperature; Wherein the second microchannel unit further receives the hydrogen gas provided by the hydrogen gas supply unit to make gas-liquid contact with the slurry to form the product.
3. The reaction system for continuous production of a cycloalkane-based amine-based hardener of claim 2, wherein the first microchannel unit receives only the slurry and performs preheating temperature rise on the slurry, and the first microchannel unit does not receive the hydrogen.
4. The reaction system for the continuous preparation of a cycloalkane-based amine hardener of claim 2, wherein the microchannel reactor module further comprises: A third microchannel unit connected in series to the rear side of the second microchannel unit, receiving the product comprising 4,4' -diamino-dicyclohexylmethane, and cooling the product from the second temperature to a third temperature of no greater than 50 ℃.
5. The reaction system for continuous preparation of a cycloalkane-based amine hardener of claim 1 wherein the solvent is at least one selected from the group consisting of tetrahydrofuran, methanol, ethanol, isopropanol, 1, 4-dioxane, cyclohexane, toluene, dimethylformamide, dimethyl sulfoxide, and ethyl acetate, wherein the catalyst has a carrier and a noble metal material supported on the carrier, and the carrier is at least one selected from the group consisting of aluminum oxide, titanium dioxide, silicon dioxide, zinc oxide, activated carbon, carbon black, and carbon nanotubes.
6. The reaction system for continuous production of a cycloalkane-based amine-based hardener of claim 1, wherein a weight ratio between the raw material and the solvent in the slurry is 1:1.5 to 10, and the catalyst is used in an amount of 1% to 20% by weight of the raw material.
7. The reaction system for continuous production of a cycloalkane-based amine-based hardener of claim 1, wherein a feed flow rate of the slurry fed to the microchannel reactor module by the slurry feeding unit is between 5ml/min and 20ml/min.
8. The reaction system for continuous production of a cycloalkane-based amine-based hardener of claim 1, wherein a reaction temperature of the hydrogenation reaction of the slurry by heating the slurry by the microchannel reactor module is between 50 ℃ and 200 ℃, and a residence time of the slurry in the microchannel reactor module is between 15 seconds and 300 seconds.
9. The reaction system for the continuous production of a cycloalkane-based amine-based hardener of claim 8, wherein the reaction temperature of the hydrogenation reaction of the slurry by the microchannel reactor module by heating is between 150 ℃ and 200 ℃, and the residence time of the slurry in the microchannel reactor module is between 40 seconds and 150 seconds.
10. The reaction system for continuous production of a cycloalkane-based amine-based hardener of claim 1, wherein a flow rate of hydrogen gas by the hydrogen gas supply unit into the microchannel reactor module is between 500ml/min and 680ml/min, and a pressure of hydrogen gas in the microchannel reactor module is between 10 bar and 100 bar.
11. The reaction system for the continuous production of a cycloalkane-based amine hardener of claim 1, further comprising: A product buffer unit connected to the back side of the microchannel reactor module to receive the product comprising 4,4' -diamino-dicyclohexylmethane; a product filtration unit to receive the product of the product buffer unit and filter the product to form a purified product and additionally form a reflux catalyst, wherein the reflux catalyst is configured to reflux to the slurry feed unit to mix with the slurry and reenter the microchannel reactor module, and A product collection unit that collects the purified product; Wherein, 4' -diamino-dicyclohexylmethane is a naphthenic amine hardener.
12. A method for continuously preparing a cycloalkane-based amine hardener, the method comprising: providing a microchannel reactor module; Providing a slurry to the microchannel reactor module, the slurry comprising a feedstock, a solvent, and a catalyst, and the feedstock being 4,4' -diaminodiphenylmethane, and Hydrogen is provided to the microchannel reactor module and is contacted with the slurry in a gas-liquid contact and hydrogenated to form a product comprising 4,4' -diamino-dicyclohexylmethane.

Description

Reaction system and method for continuously preparing naphthenic amine hardener Technical Field The invention relates to a chemical reaction system, in particular to a reaction system for continuously preparing a naphthenic amine hardener and a preparation method thereof. Background PACM (4, 4' -diamino-dicyclohexylmethane) is an important alicyclic diamine organic intermediate, and is widely applied to the manufacture of high-performance polyurethane and used as an epoxy resin curing agent. Since the chemical structure thereof has an alicyclic structure and does not contain pi electrons in an aromatic compound, it can exhibit excellent properties such as oxidation resistance, low dielectric constant, good solubility, low refractive index, low optical loss and good flexibility. In industrial production, PACM is usually produced by hydrogenation of MDA (4, 4' -diaminodiphenylmethane) at high temperature and pressure. PACM has three stereoisomers, trans-trans, cis-trans and cis-cis, respectively, where trans-trans is the thermodynamically most stable and most productive isomer. In industry, PACM is usually present as a mixture of isomers, the proportion of which affects the properties and the use of the final product. PACM is classified into various grades, such as PACM20 and PACM50, according to the content of the trans-trans isomer, wherein PACM20 (trans-trans isomer content about 20%) is commonly used to make polyurethane coatings with stable properties. Because of the complex and costly process of isomer separation, current research is focused on directly obtaining stable PACM20 products by catalytic hydrogenation. In the prior art, the conventional batch hydrogenation reactor has the problem of low contact efficiency of hydrogen and liquid in the hydrogenation process, and as the volume of the tank body increases, the heat dissipation efficiency is reduced, so that the hydrogenation reaction efficiency is low, and undesirable side reactions such as deamination or polycondensation easily occur, thereby influencing the yield of PACM. Likewise, fixed bed reactors have problems such as localized overheating, incomplete pretreatment of the catalyst bed, or fraying and accumulation of fluid bed catalyst. Disclosure of Invention The invention aims to solve the technical problem of providing a reaction system for continuously preparing a naphthenic amine-based hardener and a preparation method thereof, aiming at the defects of the prior art, wherein the reaction system adopts a microchannel reactor with high efficiency, high quality and high heat transmission efficiency so as to improve the contact efficiency of hydrogen and liquid and the heat conduction efficiency in the reaction process, thereby improving the yield of PACM and reducing the occurrence of side reactions. In order to solve the technical problems, one technical scheme adopted by the invention is to provide a reaction system for continuously preparing a naphthenic amine-based hardener, which comprises a micro-channel reactor module, a slurry feeding unit for providing slurry to the micro-channel reactor module, wherein the slurry comprises raw materials, a solvent and a catalyst, the raw materials are 4,4 '-diaminodiphenyl Methane (MDA), and a hydrogen supply unit for providing hydrogen to the micro-channel reactor module to be in gas-liquid contact with the slurry and perform hydrogenation reaction to form a product containing 4,4' -diamino-dicyclohexylmethane (PACM). Optionally, the micro-channel reactor module further comprises a first micro-channel unit used for receiving the slurry provided by the slurry feeding unit and carrying out preheating heating operation on the slurry, wherein the slurry is preheated from a first temperature of feeding to a second temperature, the first temperature is room temperature, the second temperature is 50-200 ℃, and a second micro-channel unit connected in series to the rear side of the first micro-channel unit and used for receiving the slurry with the second temperature, and the second micro-channel unit is used for keeping the temperature of the slurry at the second temperature. Optionally, the second microchannel unit further receives the hydrogen gas provided by the hydrogen gas supply unit to make gas-liquid contact with the slurry to form the product. Optionally, the first microchannel unit only receives the slurry and performs preheating temperature rise on the slurry, and the first microchannel unit does not receive the hydrogen. Optionally, the microchannel reactor module further comprises a third microchannel unit in series with the back side of the second microchannel unit, receiving the product comprising 4,4' -diamino-dicyclohexylmethane, and cooling the product from the second temperature to a third temperature of no greater than 50 ℃. Optionally, the solvent is at least one selected from the group consisting of tetrahydrofuran, methanol, ethanol, isopropanol, 1, 4-dioxane, cyclohexane, toluene