CN111196761B - Method and reaction device for preparing 3-aminopropanol - Google Patents

Method and reaction device for preparing 3-aminopropanol Download PDF

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CN111196761B
CN111196761B CN201811367131.8A CN201811367131A CN111196761B CN 111196761 B CN111196761 B CN 111196761B CN 201811367131 A CN201811367131 A CN 201811367131A CN 111196761 B CN111196761 B CN 111196761B
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ammonia
rectifying tower
liquid
gas
hydroxypropionitrile
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CN111196761A (en
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丁云杰
马雷
严丽
程显波
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Dalian Institute of Chemical Physics of CAS
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Dalian Institute of Chemical Physics of CAS
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C213/00Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
    • C07C213/02Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton by reactions involving the formation of amino groups from compounds containing hydroxy groups or etherified or esterified hydroxy groups

Abstract

The application discloses a method for preparing 3-aminopropanol, which comprises the steps of carrying out catalytic hydrogenation on a raw material containing 3-hydroxypropionitrile under the ammonia-facing condition, and separating and purifying an obtained product to obtain 3-aminopropanol and liquid ammonia and/or 3-hydroxypropionitrile for recycling. The method can realize the recycling of the reaction medium ammonia.

Description

Method and reaction device for preparing 3-aminopropanol
Technical Field
The application relates to a method and a reaction device for preparing 3-aminopropanol by using 3-hydroxypropionitrile as a raw material, in particular to a reaction process for producing 3-aminopropanol by hydrogenating 3-hydroxypropionitrile under the ammonia-contacting condition and a method for separating and purifying a product, belonging to the technical field of chemical material preparation.
Background
3-aminopropanol is used as an important chemical and pharmaceutical intermediate and is widely applied to the industries of medicines, pesticides, dyes, surfactants, daily cosmetics and the like; specifically, 3-aminopropanol is used as a drug intermediate and can be used for synthesizing anticancer drugs such as cyclophosphamide, cardiodine and DL-panthenol (provitamin B5); 3-aminopropanol is used as fine chemical intermediate, and can also be used for producing panthenol and pantothenic acid derivatives in daily chemicals. Along with the continuous progress of medicine and the improvement of living standard of people in recent years, the application of 3-aminopropanol in drug development and daily chemical product development is more and more extensive, and the market demand of 3-aminopropanol is greatly driven.
The methods currently used for the production of 3-aminopropanol are mainly the following: (1) Preparing 3-aminopropanol by catalytic hydrogenation of 3-hydroxypropionitrile; (2) Synthesizing ketoxime by using methyl isobutyl ketone or cyclohexanone as a raw material, then condensing the ketoxime with acrylonitrile, and preparing 3-aminopropanol by catalytic hydrocracking; (3) 3-aminopropanol is synthesized by taking 3-aminopropionic acid ethyl ester and 2-cyanoethanol as raw materials. The latter two methods have the problems of high raw material cost, complex process route or low yield, and the like, so the 3-hydroxypropionitrile catalytic hydrogenation method is usually adopted in the current industrial production.
German patent DE573983 reports transition metal synthesis hydrogenation catalysts for the hydrogenation of 3-hydroxypropionitrile, the product obtained being purified by fractional distillation. Switzerland patent CH244837 and German patent DE2655794 report catalytic hydrogenation of 3-hydroxypropionitrile, and it was found that when liquid ammonia was added during the hydrogenation, the formation of secondary amines as by-products was suppressed and the selectivity of 3-aminopropanol was improved. This is because the presence of liquid ammonia inhibits the occurrence of amination reactions between 3-aminopropanol molecules. Japanese patents JP2002201164 and JP05163213 use Raney cobalt catalysts for the catalytic hydrogenation of 3-hydroxypropionitrile in the presence of ammonia, increasing the yield of 3-aminopropanol. Japanese patent JP59210258 reports the catalytic hydrogenation of hydroxypropionitrile as raw material to produce 3-aminopropanol, but the reaction by-product is more and the yield of 3-aminopropanol is only 70%. Chinese patent CN103261148A published by BASF corporation reports a method for producing and purifying 3-aminopropanol, wherein a cobalt-based catalyst is adopted, P, mn or alkaline earth metal is added as an auxiliary agent, and a reaction product is distilled in two or more sections to obtain high-purity 3-aminopropionitrile, so as to meet the quality standard of cosmetics and pharmaceutical industry.
The existing production method is used for preparing 3-aminopropanol by hydrogenating 3-hydroxypropionitrile, and has the problems of poor catalyst activity, low 3-aminopropanol yield, high selectivity of byproducts, difficult product separation and the like.
Disclosure of Invention
According to one aspect of the application, a method for preparing 3-aminopropanol from a raw material containing 3-hydroxypropionitrile is provided, and the method can realize the recycling of reaction medium ammonia.
The method for preparing 3-aminopropanol is characterized in that,
under the ammonia-contacting condition, the raw material containing 3-hydroxypropionitrile is subjected to catalytic hydrogenation, and the obtained product is separated and purified to obtain 3-aminopropanol and recycled liquid ammonia and/or 3-hydroxypropionitrile.
Alternatively, the product comprises 3-hydroxypropionitrile, liquid ammonia and hydrogen as the main products, together with 3-aminopropanol and by-products, which may be water, n-propylamine, propylenediamine, dipropylenetriamine (H) 2 N(CH 2 ) 3 NH(CH 2 ) 3 NH 2 ) And hydroxypropyl propylenediamine (HO (CH) 2 ) 3 NH(CH 2 ) 3 NH 2 )。
Optionally, the separating and purifying comprises:
(1) Carrying out gas-liquid separation on a product to be treated to obtain a gas-phase mixture and a liquid-phase mixture;
(2) And (3) deaminating the gas-phase mixture and the liquid-phase mixture, and separating to obtain liquid ammonia and hydrogen for recycling.
Optionally, the pressure of the deamination is 0.1 to 3.0MPa.
Optionally, the upper pressure limit for deamination is selected from 3.0Mpa, 2.0Mpa, 1.0Mpa, 0.8Mpa, 0.5Mpa, or 0.3Mpa; the lower limit is selected from 2.0MPa, 1.0MPa, 0.8MPa, 0.5MPa, 0.3MPa or 0.1MPa.
Optionally, the deamination is performed in a rectification column.
Optionally, the separation and purification further comprises:
(3) And (3) performing ammonia stripping treatment on other substances obtained by the deamination separation in the step (2), separating to obtain ammonia and water, recovering ammonia, and recycling the liquid ammonia obtained by separation.
Optionally, the ammonia stripping pressure is 0.1 to 3.0MPa.
Optionally, the upper pressure limit of the ammonia stripping is selected from 3.0Mpa, 2.0Mpa, 1.0Mpa, 0.8Mpa, 0.5Mpa or 0.3Mpa; the lower limit is selected from 2.0MPa, 1.0MPa, 0.8MPa, 0.5MPa, 0.3MPa or 0.1MPa.
Optionally, the ammonia stripping is performed in a rectification column.
Optionally, the separating and purifying further comprises:
(4) Recovering ammonia in the step (3), and rectifying other substances obtained by separation to obtain a product amine and unreacted 3-hydroxypropionitrile;
the 3-hydroxypropionitrile is recycled.
Optionally, the pressure for ammonia recovery is 0.1 to 3.0MPa.
Optionally, the upper pressure limit for ammonia recovery is selected from 3.0Mpa, 2.0Mpa, 1.0Mpa, 0.8Mpa, 0.5Mpa, or 0.3Mpa; the lower limit is selected from 2.0MPa, 1.0MPa, 0.8MPa, 0.5MPa, 0.3MPa or 0.1MPa.
Optionally, the ammonia recovery is performed in a rectification column.
Optionally, the separation and purification comprises:
the reaction product is separated and purified by a gas-liquid separator, a rectifying tower for deamination, a rectifying tower for steam stripping and a rectifying tower for ammonia recovery, and the separated ammonia water or liquid ammonia is recycled.
Optionally, the separation and purification comprises: the reaction product enters a gas-liquid separator, and a gas-phase mixed product and a liquid-phase mixed product are flashed; the gas-phase mixed product and the liquid-phase mixed product enter a rectifying tower for deamination, the separated liquid ammonia and hydrogen can be recycled, and the rest mixture enters the rectifying tower for ammonia stripping; separating ammonia and water from the mixture in a rectifying tower for ammonia stripping, enabling the mixture to flow out of the tower top and enter the rectifying tower for ammonia recovery, and further separating liquid ammonia for recycling; discharging the rest products from the bottom of the rectifying tower for ammonia stripping, and performing subsequent rectification to obtain the final product amine; wherein unreacted 3-hydroxypropionitrile is recycled.
Optionally, the conditions of the catalytic hydrogenation comprise:
the temperature is 50-200 ℃, the pressure is 3.0-30.0 MPa, and the molar ratio of ammonia to 3-hydroxypropionitrile is 1.0.
Alternatively, the molar ratio of 3-hydroxypropionitrile to ammonia is 1.0: 1.0-20.0: 1.0.
alternatively, the upper limit of the molar ratio of 3-hydroxypropionitrile to ammonia is selected from 80.0:1.0, 70.0:1.0, 60.0:1.0, 50.0:1.0, 40.0:1.0, 30.0:1.0, 20.0:1.0, 15.0:1.0, 10.0:1.0 or 10.0:10.0; the lower limit is selected from 70.0:1.0, 60.0:1.0, 50.0:1.0, 40.0:1.0, 30.0:1.0, 20.0:1.0, 15.0:1.0, 10.0:1.0, 10.0:10.0 or 10.0:20.0.
optionally, the liquid hourly space velocity of the 3-hydroxypropionitrile is 0.1-10.0 h -1 ,H 2 The volume space velocity of the reactor is 50.0 to 2000.0h -1
Alternatively, the upper limit of the liquid hourly space velocity of 3-hydroxypropionitrile is selected from 10.0h -1 、8.0h -1 、5.0h -1 、3.0h -1 、1.0h -1 、0.8h -1 、0.6h -1 、0.5h -1 Or 0.3h -1 (ii) a The lower limit is selected from 8.0h -1 、5.0h -1 、3.0h -1 、1.0h -1 、0.8h -1 、0.6h -1 、0.5h -1 、0.3h -1 Or 0.1h -1
Alternatively, H 2 The upper limit of the volume space velocity is selected from 2000.0h -1 、1800.0h -1 、1500.0h -1 、1000.0h -1 、800.0h -1 、600.0h -1 、200.0h -1 Or 100.0h -1 (ii) a The lower limit is selected from 1800.0h -1 、1500.0h -1 、1000.0h -1 、800.0h -1 、600.0h -1 、200.0h -1 、100.0h -1 Or 50.0h -1
Optionally, the liquid hourly space velocity of the 3-hydroxypropionitrile is 0.2-2.0 h -1 ,H 2 The volume space velocity of the reactor is 200 to 800.0h -1
Optionally, the feedstock is preheated.
Alternatively, the catalytic hydrogenation is carried out in a gas-liquid-solid three-phase reactor.
Optionally, the catalytic hydrogenation catalyst is a supported catalyst;
optionally, the catalyst comprises an active component and a support;
the active component comprises an active metal element; the active metal elements include M and Re; m is at least one selected from Ni, co and Cu;
the carrier is selected from at least one of inorganic porous materials.
Optionally, the catalyst is subjected to an activation treatment.
As an embodiment, the method for preparing 3-aminopropanol from the raw material containing 3-hydroxypropionitrile is characterized by comprising the following steps:
s1) contacting a raw material containing 3-hydroxypropionitrile with a catalyst in a reactor, and carrying out catalytic hydrogenation reaction under the ammonia-contacting condition to generate a reaction product mainly containing 3-aminopropanol;
s2) separating and purifying the reaction product by a gas-liquid separator, a rectifying tower for deamination, a rectifying tower for steam stripping and a rectifying tower for ammonia recovery to obtain 3-aminopropanol; the separated ammonia water or liquid ammonia can be recycled.
Optionally, the step S1) comprises reacting with 3-ammoniaThe reaction products based on propyl alcohol include unreacted 3-hydroxypropionitrile, liquid ammonia and hydrogen, together with 3-aminopropanol and by-products, which may be water, n-propylamine, propylenediamine, dipropylenetriamine (H) 2 N(CH 2 ) 3 NH(CH 2 ) 3 NH 2 ) And hydroxypropyl propylenediamine (HO (CH) 2 ) 3 NH(CH 2 ) 3 NH 2 )。
Optionally, step S2) comprises the steps of:
s21) enabling the reaction product to enter a gas-liquid separator, and flashing to obtain a gas-phase mixed product and a liquid-phase mixed product; the gas-phase mixed product and the liquid-phase mixed product enter a rectifying tower for deamination, and a recycling part and a continuous separation part are separated; the recycling part comprises liquid ammonia and hydrogen;
s22) the continuous separation part enters a rectifying tower for ammonia stripping; continuously separating ammonia and water from the separation part in a rectifying tower for ammonia stripping, enabling the ammonia and the water to flow out of the tower top and enter the rectifying tower for ammonia recovery, and further separating liquid ammonia for recycling;
s23) discharging the rest products from the bottom of the rectifying tower for ammonia stripping, and performing subsequent rectification to obtain a final product 3-aminopropanol, wherein the 3-hydroxypropionitrile obtained by rectification is recycled.
Optionally, the operating pressure of the distillation tower for deamination is 0.1-3.0 MPa; the operating pressure of the rectifying tower for ammonia stripping is 0.1-3.0 MPa; the operating pressure of the rectifying tower for ammonia recovery is 0.1-3.0 MPa.
Optionally, the upper limit of the distillation column operating pressure for deamination is selected from 3.0Mpa, 2.0Mpa, 1.0Mpa, 0.8Mpa, 0.5Mpa, or 0.3Mpa; the lower limit is selected from 2.0MPa, 1.0MPa, 0.8MPa, 0.5MPa, 0.3MPa or 0.1MPa.
Optionally, the upper limit of the distillation column operating pressure for ammonia stripping is selected from 3.0Mpa, 2.0Mpa, 1.0Mpa, 0.8Mpa, 0.5Mpa, or 0.3Mpa; the lower limit is selected from 2.0MPa, 1.0MPa, 0.8MPa, 0.5MPa, 0.3MPa or 0.1MPa.
Optionally, the upper limit of the distillation column operating pressure for ammonia recovery is selected from 3.0Mpa, 2.0Mpa, 1.0Mpa, 0.8Mpa, 0.5Mpa, or 0.3Mpa; the lower limit is selected from 2.0MPa, 1.0MPa, 0.8MPa, 0.5MPa, 0.3MPa or 0.1MPa.
Optionally, the catalyst comprises an active component, an auxiliary agent and a carrier; the active component comprises an active metal element; the active metal element includes Ni and/or Cu; the auxiliary agent comprises at least one of metal elements Co, fe, cr, re, W, ru, B, mg, ba, mn, la and Mo; the carrier is selected from Al 2 O 3 、SiO 2 、Al 2 O 3 -SiO 2
Optionally, the catalyst is prepared by loading the active component precursor and the auxiliary agent precursor on a carrier through an impregnation method or a precipitation method.
Alternatively, the catalyst precursor used is a corresponding water-soluble compound, for example a nitrate, chloride, acetate or sulphate of the above-mentioned metals.
Alternatively, the carrier used may be in the form of powder, sphere, ring, porous, cylinder or strip.
Alternatively, the catalyst precursor is prepared by supporting the active component or the auxiliary agent on the carrier by an impregnation method or a precipitation method. Taking the dipping method as an example, the catalyst precursor is dissolved in a proper amount of water to prepare a precursor liquid, and the carrier is dipped by the precursor liquid. Then the hydrogenation catalyst is prepared through the steps of drying and roasting.
Optionally, the catalyst calcination temperature is 300-700 ℃.
Optionally, the catalyst calcination temperature is 400-550 ℃.
Optionally, the catalyst is activated in hydrogen-containing atmosphere before use, the activation temperature is 200-800 ℃, the pressure is 0.1-1.0 MPa, and the volume space velocity of hydrogen gas is 500-5000 h -1 The activation time is 0.5-10.0 h.
Optionally, the catalyst is activated in a hydrogen atmosphere before use, and the activation temperature is 400-600 ℃; the pressure in the activation process is 0.1-0.5 MPa; the volume space velocity of hydrogen gas is 1000-3000 h -1 (ii) a The reduction time is 1.5 to 6.0 hours.
Alternatively, the reaction conditions are:
the reaction pressure is 3.0-30 MPa;
the reaction temperature is 50-200 ℃;
NH 3 the mol ratio of the 3-hydroxypropionitrile is 1.0;
H 2 the volume space velocity is 50.0-2000.0 h -1
The liquid space velocity of the 3-hydroxypropionitrile is 0.1 to 10.0h -1
Alternatively, the molar ratio of 3-hydroxypropionitrile to ammonia is 1.0: 1.0-20.0: 1.0.
optionally, the molar ratio of 3-hydroxypropionitrile to ammonia in the 3-hydroxypropionitrile-containing feed in step S1) is 15:1.0.
alternatively, the upper limit of the molar ratio of 3-hydroxypropionitrile to ammonia is selected from 80.0:1.0, 70.0:1.0, 60.0:1.0, 50.0:1.0, 40.0:1.0, 30.0:1.0, 20.0:1.0, 15.0:1.0, 10.0:1.0 or 10.0:10.0; the lower limit is selected from 70.0:1.0, 60.0:1.0, 50.0:1.0, 40.0:1.0, 30.0:1.0, 20.0:1.0, 15.0:1.0, 10.0:1.0, 10.0:10.0 or 10.0:20.0.
optionally, the liquid hourly space velocity of the 3-hydroxypropionitrile is 0.1-10.0 h -1 ,H 2 The volume space velocity of the reactor is 50.0 to 2000.0h -1
Alternatively, the upper limit of the liquid hourly space velocity of 3-hydroxypropionitrile is selected from 10.0h -1 、8.0h -1 、5.0h -1 、3.0h -1 、1.0h -1 、0.8h -1 、0.6h -1 、0.5h -1 Or 0.3h -1 (ii) a The lower limit is selected from 8.0h -1 、5.0h -1 、3.0h -1 、1.0h -1 、0.8h -1 、0.6h -1 、0.5h -1 、0.3h -1 Or 0.1h -1
Alternatively, H 2 The upper limit of the volume space velocity is selected from 2000.0h -1 、1800.0h -1 、1500.0h -1 、1000.0h -1 、800.0h -1 、600.0h -1 、200.0h -1 Or 100.0h -1 (ii) a The lower limit is selected from 1800.0h -1 、1500.0h -1 、1000.0h -1 、800.0h -1 、600.0h -1 、200.0h -1 、100.0h -1 Or 50.0h -1
Optionally, the liquid hourly space velocity of the 3-hydroxypropionitrile is 0.2-2.0 h -1 ,H 2 The volume space velocity of the reactor is 200 to 800.0h -1
Optionally, the reactor is selected from an autoclave reactor, a fixed bed reactor, a fluidized bed reactor.
Optionally, the reaction temperature is 50-200 ℃, and the reaction pressure is 3.0-30 Mpa.
Optionally, the reaction temperature is 70-130 ℃, and the reaction pressure is 7.0-20 Mpa.
Optionally, the raw material containing 3-hydroxypropionitrile is mixed with ammonia, preheated by a raw material heater, and then fed into the reactor.
Optionally, step S1) comprises the steps of:
s11) placing the activated catalyst in a reactor, introducing hydrogen, pressurizing to 3.0-30.0 MPa, and adjusting the reaction temperature to 50-200 ℃;
s12) preheating the raw materials of 3-hydroxypropionitrile and ammonia in a raw material heater to xx-xx ℃, and pumping the preheated raw materials into a reactor for reaction.
Alternatively, the raw materials of 3-hydroxypropionitrile and liquid ammonia in step S12) are dissolved and diluted without adding any solvent. The feeding mode can be respectively feeding 3-hydroxypropionitrile and liquid ammonia, or feeding 3-hydroxypropionitrile and liquid ammonia in a mixing way.
As an embodiment, the method comprises the steps of:
(1) Activating a hydrogenation catalyst in a reducing atmosphere, and placing the activated catalyst in a hydrogenation reactor; introducing hydrogen, pressurizing to the reaction pressure of 3.0-30.0 MPa, and adjusting the reaction temperature to 50-200 ℃;
(2) Preheating raw materials, namely 3-hydroxypropionitrile and liquid ammonia, by a raw material heater, then feeding the preheated raw materials into a hydrogenation reactor, and contacting the preheated raw materials with a catalyst under the conditions of temperature and pressure in the step (1) to obtain a reaction mixed product;
(3) The reaction mixed product enters a gas-liquid separator through a control valve, and a gas-phase mixed product and a liquid-phase mixed product are flashed out;
(4) The gas-phase mixed product enters the upper part of a rectifying tower for deamination, and the liquid-phase mixed product enters the middle lower part of the rectifying tower for deamination; unreacted liquid ammonia and hydrogen flow out from the top of the tower after separation and can be recycled; the rest part of the mixture flows out from the bottom of the tower and enters a rectifying tower for ammonia stripping;
(5) Separating ammonia and water from the mixture in a rectifying tower for ammonia stripping, enabling the mixture to flow out of the tower top and enter the rectifying tower for ammonia recovery, and separating liquid ammonia for recycling; discharging the rest products from the bottom of the rectifying tower for ammonia stripping, and obtaining the product 3-aminopropanol by a rectifying system, wherein the unreacted 3-hydroxypropionitrile can be recycled.
Optionally, the reaction temperature in the step (1) is 50-200 ℃, and preferably the reaction temperature is 70-130 ℃; the reaction pressure is 3.0 to 30.0MPa, preferably 7.0 to 20.0MPa.
Optionally, the hydrogenation catalyst in the step (1) is a heterogeneous supported catalyst, and comprises an active component, an auxiliary agent and a carrier; the active component can be one or two of Ni or Cu, and is preferably Ni-Cu bimetal; the auxiliary agent can be one or more of Co, fe, cr, re, W, ru, B, mg, ba, mn, la and Mo, and the preferable auxiliary agent is Cr, re, B, mn and La; the carrier may be Al 2 O 3 、SiO 2 Or Al 2 O 3 -SiO 2 Preferably, the carrier is Al 2 O 3 -SiO 2
Alternatively, the catalyst precursors used are the corresponding water-soluble compounds, for example the nitrates, chlorides, acetates or sulfates of the abovementioned metals.
Alternatively, the carrier used may be in the form of powder, sphere, ring, porous, cylinder or strip.
Alternatively, the catalyst precursor is prepared by supporting the active component or the auxiliary agent on the carrier by an impregnation method or a precipitation method. Taking the dipping method as an example, the catalyst precursor is dissolved in a proper amount of water to prepare a precursor liquid, and the carrier is dipped by the precursor liquid. Then drying and roasting to prepare the hydrogenation catalyst.
Alternatively, the catalyst calcination temperature is usually 300 to 700 ℃, preferably 400 to 550 ℃.
Optionally, the catalyst is activated in a hydrogen atmosphere before use, wherein the activation temperature is 300-800 ℃, and preferably the activation temperature is 400-600 ℃; the pressure in the activation process can be 0.1-1.0 MPa, and the preferred pressure is 0.1-0.5 MPa; the volume space velocity of the hydrogen gas can be 500-5000 h -1 Preferably 1000 to 3000 hours -1 (ii) a The reduction time is 0.5 to 10.0h, preferably 1.5 to 6.0h.
Alternatively, in the step (2), the raw materials of 3-hydroxypropionitrile and liquid ammonia are dissolved and diluted without adding any solvent. The feeding mode can be respectively feeding 3-hydroxypropionitrile and liquid ammonia, or feeding 3-hydroxypropionitrile and liquid ammonia in a mixing way.
Optionally, in the step (2), the raw material 3-hydroxypropionitrile, the liquid ammonia and the hydrogen gas are mixed and then preheated by a raw material heater. The preheating temperature of the raw material heater is the same as the set reaction temperature. The reaction conditions are illustrated by taking a fixed bed reactor as an example: the liquid volume space velocity of the 3-hydroxypropionitrile is 0.1 to 10.0h -1 Preferably 0.2 to 2.0h -1 (ii) a The volume space velocity of the hydrogen gas is 50.0 to 2000.0h -1 Preferably 200.0 to 800.0h -1 (ii) a The molar ratio of ammonia to 3-hydroxypropionitrile is from 1.0 to 80.0, preferably from 1.0 to 20.0.
Optionally, the reaction mixture product in step (2) comprises unreacted 3-hydroxypropionitrile, liquid ammonia and hydrogen, together with 3-aminopropanol and by-products, which may be water, n-propylamine, propylenediamine, dipropylenetriamine (H) 2 N(CH 2 ) 3 NH(CH 2 ) 3 NH 2 ) And hydroxypropyl propylenediamine (HO (CH) 2 ) 3 NH(CH 2 ) 3 NH 2 )。
Optionally, the operating pressure of the distillation tower for deamination is 0.1-3.0 MPa; the operating pressure of the rectifying tower for ammonia stripping is 0.1-3.0 MPa; the operating pressure of the rectifying tower for recovering ammonia is 0.1-3.0 MPa.
According to another aspect of the application, a reaction device is provided, which is characterized by comprising a raw material heater, a hydrogenation reactor containing a hydrogenation catalyst, and a product separation, purification and recovery device;
the product separation, purification and recovery device comprises a gas-liquid separator, a rectifying tower for deamination, a rectifying tower for steam stripping and a rectifying tower for ammonia recovery;
the raw material heater comprises a feeding hole, a heating system and a discharging hole; mixing raw materials of 3-hydroxypropionitrile and liquid ammonia, then feeding the mixture into a raw material heater, and feeding the preheated material into a hydrogenation reactor through a discharge port; under the action of a hydrogenation catalyst, the raw material 3-hydroxypropionitrile is hydrogenated and converted into a reaction mixed product; the reaction mixed product enters a product separation, purification and recovery device through a discharge hole of the reactor; the separated and purified liquid ammonia or 3-hydroxypropionitrile can be recycled as raw materials.
As an embodiment, the hydrogenation reactor is a gas-liquid-solid three-phase reactor, and the reactor may be an autoclave type, a fixed bed or a fluidized bed reactor, preferably a fixed bed reactor; the reactor can be suitable for hydrogenation reaction at the temperature of 20-500 ℃ and the pressure of 0.1-40 MPa; the reactor is characterized by high mass transfer efficiency and good heat transfer property, and is suitable for catalytic hydrogenation reaction under the condition of ammonia.
The fixed bed reactor mainly comprises a feed inlet, a cylinder body, a catalyst supporting disk, a liquid distribution pipe, a gas-liquid distribution disk, a temperature monitoring port and a discharge port.
The product separation, purification and recovery device comprises a gas-liquid separator, a deamination rectifying tower, an ammonia stripping rectifying tower and an ammonia recovery rectifying tower.
The separation, purification and recovery processes are that the reaction mixed product is discharged from a discharge hole of the reactor and enters a gas-liquid separator, and the gas-phase mixed product and the liquid-phase mixed product are flashed; the gas-phase mixed product enters the upper part of a rectifying tower for deamination, the liquid-phase mixed product enters the middle lower part of the rectifying tower for deamination, the separated liquid ammonia and hydrogen flow out from the top of the tower and can be recycled, and the rest mixture flows out from the bottom of the tower and enters the rectifying tower for ammonia stripping; separating ammonia and water from the mixture in a rectifying tower for ammonia stripping, enabling the mixture to flow out of the tower top and enter the rectifying tower for ammonia recovery, and further separating liquid ammonia for recycling; discharging the rest products from the bottom of the rectifying tower for ammonia stripping, and performing subsequent rectification to obtain the final product 3-aminopropanol, wherein the unreacted 3-hydroxypropionitrile can be recycled.
And the outlet material at the bottom of the rectifying tower for deamination enters the rectifying tower for ammonia stripping, and the top of the rectifying tower is provided with a recovered liquid ammonia outlet.
An ammonia and water outlet is formed in the top of the rectifying tower for ammonia stripping, and materials at the ammonia and water outlet enter the rectifying tower for ammonia recovery; the bottom of the rectifying tower for ammonia stripping is provided with a product outlet after deamination.
The top of the rectifying tower for ammonia recovery is provided with a recovered liquid ammonia outlet, and the bottom of the rectifying tower is a wastewater outlet.
The technical scheme in the application can be applied to the hydrogenation of 3-hydroxypropionitrile to prepare 3-aminopropanol under the ammonia critical condition, but the method is not limited to the reaction, and other alcohol nitrile hydrogenation processes are also within the scope of the invention.
The beneficial effects that this application can produce include:
compared with the prior art, the catalyst has high activity, the liquid ammonia is recycled, the conversion rate of the 3-hydroxypropionitrile is obviously improved, the yield of the target product 3-aminopropanol is improved, the service life of the catalyst is prolonged, the purity of the product 3-aminopropanol is improved, and the energy consumption of the reaction is reduced.
Detailed Description
The present application will be described in detail with reference to examples, but the present application is not limited to these examples.
The raw materials in the examples of the present application were all purchased commercially, unless otherwise specified.
The analysis method in the examples of the present application is as follows:
the analysis is carried out by an Agilent 7890 gas chromatograph, a chromatographic column is a DB-35 capillary chromatographic column, and a detector is a hydrogen flame detector. Quantitative analysis was performed using N, N-Dimethylformamide (DMFA) as an internal standard. .
In the examples of the present application, the 3-hydroxypropionitrile conversion and the 3-aminopropanol selectivity were calculated on a carbon molar basis;
the conversion, selectivity in the examples of the present application were calculated as follows:
Figure BDA0001868867920000111
Figure BDA0001868867920000112
wherein C0 is the molar concentration of the 3-hydroxypropionitrile before reaction, and C is the molar concentration of the 3-hydroxypropionitrile in the reaction system after reaction; n is the molar weight of the 3-aminopropanol after the reaction, and Ntotal is the molar weight of all reaction products after the reaction.
According to one embodiment of the present application, a method for preparing 3-aminopropanol starting from 3-hydroxypropionitrile is provided.
The device adopted by the invention comprises: (1) a raw material heater; (2) The gas-liquid-solid three-phase reactor for hydrogenation reaction comprises a material inlet and a material outlet; (3) A gas-liquid separator comprising a gas phase outlet and a liquid phase outlet; (4) The rectifying tower for deamination comprises a gas-phase reactant inlet, a liquid-phase reactant inlet, an ammonia outlet at the top of the tower and a reactant outlet at the bottom of the tower; (5) A rectifying column for ammonia stripping comprising a reactant inlet, a top ammonia and water outlet and a bottom reactant outlet; (6) The rectifying tower for recovering ammonia comprises an ammonia and water inlet, a tower top liquid ammonia outlet and a tower bottom process wastewater outlet; (7) hydrogenation catalyst: the active component can be one or two of Ni or Cu, and is preferably Ni-Cu bimetal; the auxiliary agent can be one or more of Co, fe, cr, re, W, ru, B, mg, ba, mn, la and Mo, and the preferable auxiliary agent is Cr, re, B, mn and La; the carrier may be Al 2 O 3 、SiO 2 Or Al 2 O 3 -SiO 2 Preferably, the carrier is Al 2 O 3 -SiO 2
The preparation of the hydrogenation catalysts in the examples is described by taking the preparation of the hydrogenation catalysts in examples 1 and 2 as an example, by an isometric impregnation method.
In example 1, addThe preparation method of the hydrogen catalyst comprises the following steps: with Ni-Re-B/Al 2 O 3 -SiO 2 The catalyst is illustrated by an isovolumetric impregnation method, the procedure is as follows, al 2 O 3 -SiO 2 Drying at 120 deg.C for 4 hr before use to obtain Ni (NO) 3 ) 2 ·6H 2 O,NH 4 ReO 4 And H 3 BO 3 With which the above-mentioned Al is impregnated 2 O 3 -SiO 2 And naturally airing the carrier, drying at 100 ℃ for 4 hours, roasting at 500 ℃ for 4 hours, and raising the temperature at the rate of 5 ℃/min. Wherein the weight percentage of Ni in the catalyst is 20%, the weight percentage of Re in the catalyst is 1.2%, and the weight percentage of B in the catalyst is 2.5%.
In example 2, the preparation method of the hydrogenation catalyst: with Ni-Cu-Re/Al 2 O 3 The catalyst is illustrated by an isovolumetric impregnation method, the procedure is as follows, al 2 O 3 Drying at 120 deg.C for 4 hr before use to obtain Ni (NO) 3 ) 2 ·6H 2 O,Cu(NO 3 ) 2 And NH 4 ReO 4 With which the above-mentioned Al is impregnated 2 O 3 And naturally airing the carrier, drying at 100 ℃ for 4 hours, roasting at 500 ℃ for 4 hours, and raising the temperature at the rate of 5 ℃/min. Wherein the weight percentage of Ni in the catalyst is 15%, the weight percentage of Cu in the catalyst is 8%, and the weight percentage of Re in the catalyst is 1.5%.
Example 1
(1) Hydrogenation catalyst Ni-Re-B/Al 2 O 3 -SiO 2 Placing in a fixed bed reactor, activating in hydrogen atmosphere at 500 deg.C under 0.1MPa and hydrogen airspeed of 2000h -1 And the activation time is 6h. After the activation is finished, the reaction temperature is adjusted to 90 ℃, and hydrogen is introduced to charge the pressure to 10MPa.
(2) The raw material is a mixture of 3-hydroxypropionitrile and liquid ammonia, wherein the molar ratio of the 3-hydroxypropionitrile to the liquid ammonia is 15. Pumping the raw material into a raw material heater, feeding the preheated raw material into a fixed bed hydrogenation reactor through a feed inlet, contacting with a catalyst, and carrying out a catalytic hydrogenation reactionTo produce a product mainly containing 3-aminopropanol. The heating temperature of the raw material heater is 90 ℃, and the hourly space velocity of the 3-hydroxypropionitrile liquid is 0.5h -1 The volume space velocity of hydrogen is 1000h -1 . The reaction mixture product comprises unreacted 3-hydroxypropionitrile, liquid ammonia and hydrogen, as well as 3-aminopropanol and by-products, which may be water, n-propylamine, propylenediamine, dipropylenetriamine (H) 2 N(CH 2 ) 3 NH(CH 2 ) 3 NH 2 ) And hydroxypropyl propylenediamine (HO (CH) 2 ) 3 NH(CH 2 ) 3 NH 2 ). The obtained reaction mixed product enters a gas-liquid separator through a discharge hole.
(3) And the reaction mixed product enters a gas-liquid separator through a control valve, a gas-phase mixed product and a liquid-phase mixed product are flashed out at 80 ℃, and enter a rectifying tower for deamination from a gas-phase reactant inlet and a liquid-phase reactant inlet respectively.
(4) A rectifying tower for deamination, wherein the pressure is 0.5MPa; the gas phase effluent at the top of the tower is ammonia and hydrogen, and the liquid phase effluent at the bottom of the tower is a reaction mixture comprising 3-hydroxypropionitrile, liquid ammonia, 3-aminopropanol, water, n-propylamine, propylenediamine and dipropylenetriamine (H) 2 N(CH 2 ) 3 NH(CH 2 ) 3 NH 2 ) And hydroxypropyl propylenediamine (HO (CH) 2 ) 3 NH(CH 2 ) 3 NH 2 ). The reaction mixture enters a rectification column for ammonia stripping.
(5) A rectifying tower for ammonia stripping, wherein the pressure is 0.3MPa; the top discharge of the tower is a mixture of ammonia and water, and enters a rectifying tower for ammonia recovery; the bottom discharge of the tower is a mixture of reaction products, and the high-purity product 3-aminopropanol is obtained by rectifying subsequent products.
(6) A rectifying tower for recovering ammonia, wherein the pressure is 0.3MPa; the tower top discharge is liquid ammonia which can be recycled; the bottom discharge is process wastewater.
The analysis result of the liquid phase product of the reaction mixed product after passing through the deamination rectifying tower and the ammonia stripping rectifying tower is as follows:
the conversion rate of 3-hydroxypropionitrile is 99.31%, and the selectivity of 3-aminopropanol is 94.50%.
Liquid phase product results:
1.64% of 3-hydroxypropionitrile, 7.36% of water, 0.64% of ammonia, 0.64% of 3-aminopropanol 88.48%, 0.46% of n-propylamine, 0.59% of propylenediamine, 0.64% of dipropylenetriamine and 0.18% of hydroxypropyl propylenediamine.
Example 2
The other operation is the same as in example 1, except that the catalyst Ni-Cu-Re/Al is used 2 O 3
Example 3
The other operations are the same as example 1, except that the catalyst is used for activation at 200 deg.C, under 1.0MPa and at 5000h hydrogen space velocity -1 And the activation time is 6h.
Example 4
The other operations are the same as example 1, except that the catalyst is used for activating at 800 deg.C under 1.0MPa and hydrogen at 500 hr -1 And the activation time is 0.5h.
Example 5
The other operation was the same as in example 1 except that the reaction temperature was 50 ℃ and the reaction pressure was 30.0MPa.
Example 6
The other operation was the same as in example 1 except that the reaction temperature was 200 ℃ and the reaction pressure was 3.0MPa.
Example 7
The other operations are the same as example 1 except that the distillation column for deamination is operated at a pressure of 0.1MPa; the operating pressure of the rectifying tower for ammonia stripping is 3.0MPa; the operating pressure of the rectification column for ammonia recovery was 0.1Mpa.
Example 8
The other operations are the same as in example 1, except that the operating pressure of the rectification column for deamination is 3.0MPa; the operating pressure of the rectifying tower for ammonia stripping is 0.1MPa; the operating pressure of the rectifying tower for ammonia recovery is 3.0MPa.
The results of analyzing the liquid phase products of the operations of examples 2 to 8 after passing the reaction mixture through the deamination rectification column and the ammonia stripping rectification column were similar to those of example 1.
Although the present application has been described with reference to a few embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the application as defined by the appended claims.

Claims (15)

1. A method for preparing 3-aminopropanol is characterized in that,
under the ammonia-facing condition, carrying out catalytic hydrogenation on a raw material containing 3-hydroxypropionitrile, and separating and purifying an obtained product to obtain 3-aminopropanol and recycled liquid ammonia and/or 3-hydroxypropionitrile;
the separation and purification comprises the following steps:
separating and purifying the reaction product by a gas-liquid separator, a rectifying tower for deamination, a rectifying tower for steam stripping and a rectifying tower for ammonia recovery, and recycling the separated ammonia water or liquid ammonia;
the reaction product enters a gas-liquid separator, and a gas-phase mixed product and a liquid-phase mixed product are flashed; the gas-phase mixed product and the liquid-phase mixed product enter a rectifying tower for deamination, the separated liquid ammonia and hydrogen can be recycled, and the rest mixture enters the rectifying tower for ammonia stripping; separating ammonia and water from the mixture in a rectifying tower for ammonia stripping, enabling the mixture to flow out of the tower top and enter the rectifying tower for ammonia recovery, and further separating liquid ammonia for recycling; discharging the rest products from the bottom of the rectifying tower for ammonia stripping, and performing subsequent rectification to obtain a final product, namely 3-aminopropanol; wherein unreacted 3-hydroxypropionitrile is recycled.
2. The method of claim 1, wherein the pressure of deamination is 0.1 to 3.0MPa.
3. The process according to claim 1, characterized in that the ammonia stripping pressure is 0.1 to 3.0MPa.
4. The method of claim 1, wherein the ammonia recovery pressure is 0.1 to 3.0MPa.
5. The process of claim 1, wherein the conditions for catalytic hydrogenation comprise:
the temperature is 50 to 200 ℃, the pressure is 3.0 to 30.0MPa, and the molar ratio of ammonia to 3-hydroxypropionitrile is 1.0:20.0 to 80.0:1.0.
6. The method of claim 1, wherein the feedstock is preheated.
7. The process according to claim 1, characterized in that the catalytic hydrogenation is carried out in a gas-liquid-solid three-phase reactor.
8. The process of claim 1, wherein the catalyst employed in the catalytic hydrogenation is a supported catalyst.
9. The method of claim 1, wherein the catalyst used in the catalytic hydrogenation comprises an active component and a support;
the active component comprises an active metal element; the active metal elements include M and Re; m is selected from at least one of Ni, co and Cu;
the carrier is selected from at least one of inorganic porous materials.
10. The method of claim 9, wherein the catalyst is subjected to an activation treatment.
11. The method according to any one of claims 1 to 10, wherein the apparatus for preparing 3-aminopropanol comprises:
a reaction unit and a separation and purification unit;
the materials enter a material inlet of the separation and purification unit through a material outlet of the reaction unit; the separation and purification unit comprises: the ammonia recovery system comprises a gas-liquid separator, a deamination rectifying tower, an ammonia stripping rectifying tower and an ammonia recovery rectifying tower;
a liquid-phase outlet of the gas-liquid separator is connected with a liquid-phase feed inlet of the deamination rectifying tower;
a gas-phase outlet of the gas-liquid separator is connected with a gas-phase feed inlet of the deamination rectifying tower;
a discharge port at the bottom of the deamination rectifying tower is connected with a feed port of the ammonia stripping rectifying tower;
liquid ammonia and hydrogen which are recycled flow out of a discharge hole at the top of the deamination rectifying tower;
and the discharge hole of the ammonia stripping rectifying tower is connected with the feed inlet of the ammonia recovery rectifying tower, so that the obtained liquid ammonia is recycled.
12. The method of claim 11, wherein the reaction unit comprises a feedstock heater and a hydrogenation reactor;
and the material enters a feeding port of the hydrogenation reactor through a discharge port of the raw material heater.
13. The method of claim 12, wherein the outlet of the hydrogenation reactor is connected to the inlet of the separation and purification unit.
14. The method of claim 11, wherein the separation and purification unit further comprises: a subsequent rectification column;
a discharge port at the bottom of the ammonia recovery rectifying tower is connected with a feed port of the subsequent rectifying tower;
the discharge hole of the subsequent rectifying tower comprises 3-aminopropanol and unreacted 3-hydroxypropionitrile, wherein the unreacted 3-hydroxypropionitrile is recycled.
15. The method of claim 11, wherein the apparatus comprises:
a raw material heater, a hydrogenation reactor, a gas-liquid separator, a deamination rectifying tower, an ammonia stripping rectifying tower, an ammonia recovery rectifying tower and a subsequent rectifying tower;
preheating raw materials by a raw material heater, and pumping the raw materials into a hydrogenation reactor containing a catalyst to obtain a reaction product;
the reaction product enters a gas-liquid separator through a control valve, and a gas-phase mixed product and a liquid-phase mixed product are flashed out; the gas-phase mixed product and the liquid-phase mixed product enter a rectifying tower for deamination, the separated liquid ammonia and hydrogen are recycled, and the rest mixture enters the rectifying tower for ammonia stripping; separating ammonia and water from the mixture in a rectifying tower for ammonia stripping, enabling the mixture to flow out of the tower top and enter the rectifying tower for ammonia recovery, and further separating liquid ammonia for recycling; discharging the rest products from the bottom of the rectifying tower for ammonia stripping, and performing subsequent rectification to obtain the final product 3-aminopropanol, wherein unreacted 3-hydroxypropionitrile is recycled.
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