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CN-121988386-A - Ammonolysis catalyst, preparation method thereof and method for preparing monoethylamine

CN121988386ACN 121988386 ACN121988386 ACN 121988386ACN-121988386-A

Abstract

The invention relates to the technical field of preparation processes of ethylamine, and discloses an ammonolysis catalyst, a preparation method thereof and a method for preparing the ethylamine, wherein the ammonolysis catalyst comprises a carrier, and an active component and an auxiliary agent which are loaded on the carrier, and is characterized in that the carrier is alumina modified by a titanium-silicon molecular sieve, wherein the content of the alumina exceeds 60wt% of the total mass of the carrier, the active component comprises nickel, the auxiliary agent comprises iridium, the content of nickel element is 15-30wt% and the content of iridium element is 0.2-2wt% based on the total weight of the ammonolysis catalyst.

Inventors

  • TANG GUOQI
  • TIAN BAOLIANG
  • FU SIXIAN
  • CAI MAO
  • SU ZIMU
  • NIU SHU
  • ZHANG WENSHENG

Assignees

  • 中国石油化工股份有限公司
  • 中石化(北京)化工研究院有限公司

Dates

Publication Date
20260508
Application Date
20241104

Claims (10)

  1. 1. The ammonolysis catalyst comprises a carrier, and an active component and an auxiliary agent which are loaded on the carrier, and is characterized in that the carrier is alumina modified by titanium-silicon molecular sieve, wherein the content of the alumina exceeds 60wt% of the total weight of the carrier, the active component comprises nickel, the auxiliary agent comprises iridium, and the content of nickel element is 15-30wt% and the content of iridium element is 0.2-2wt% based on the total weight of the ammonolysis catalyst.
  2. 2. The ammonolysis catalyst as recited in claim 1, wherein the content of alumina exceeds 75wt% of the total mass of the carrier.
  3. 3. The ammonolysis catalyst according to claim 1 or 2, wherein the content of nickel element is 18-27wt% and the content of iridium element is 0.5-1.5wt%, based on the total weight of the ammonolysis catalyst.
  4. 4. The ammonolysis catalyst as recited in any one of claims 1-3, wherein SiO 2 /TiO 2 ratio in the titanium silicalite molecular sieve is 25-40, grain size is 0.2-0.5 μm, sodium content is 0.01wt%.
  5. 5. A process for preparing an ammonolysis catalyst as claimed in any one of claims 1 to 4, characterized in that said process comprises: (1) Modifying the alumina precursor by adopting a titanium silicalite molecular sieve to obtain a titanium silicalite molecular sieve modified alumina carrier; (2) And immersing the carrier in a mixed solution, wherein the mixed solution comprises a salt containing an active component, and the salt containing the active component is nickel salt and iridium salt to obtain the supported catalyst.
  6. 6. The preparation method according to claim 5, wherein in the step (1), the modification method comprises kneading, extrusion molding, drying and calcining the titanium silicalite molecular sieve, the alumina precursor and the dilute acid solution to prepare the titanium silicalite molecular sieve modified alumina carrier.
  7. 7. The method according to claim 5, wherein in step (2), the carrier is immersed in the mixed solution and then subjected to drying, calcination and reduction treatment; Preferably, the conditions of the calcination include a temperature of 150-500 ℃.
  8. 8. A process for preparing monoethylamine, said process comprising: (1) Uniformly mixing the top diethylamine of a diethylamine refining tower in an ethanol hydro-ammoniation device with hydrogen and ammonia in the presence of the hydrogen and the ammonia, and then catalyzing the mixture by an ammonolysis catalyst in an ammonolysis reactor to perform ammonolysis reaction to prepare a reactant stream containing monoethylamine; (2) The gas-liquid separation tank after the reactant flow containing the ethylamine is returned to the ethanol hydro-ammonification reactor enters a subsequent separation process, or the reactant flow containing the ethylamine is subjected to gas-liquid separation and is returned to the deamination tower for refining, or the reactant flow containing the ethylamine is subjected to gas-liquid separation and deamination and is returned to the ethylamine refining tower for refining.
  9. 9. The process according to claim 8, wherein the ammonolysis reaction conditions include a reaction temperature of 130-200 ℃ and a reaction pressure of 1-15MPa, preferably a reaction temperature of 140-180 ℃ and a reaction pressure of 3-10MPa; And/or, the space velocity of the feed liquid phase volume of diethylamine is 0.01m 3 /(m 3 ·h)-1m 3 /(m 3 h), preferably 0.1m 3 /(m 3 ·h)-0.6m 3 /(m 3 h); And/or the molar ratio of hydrogen to liquid ammonia to diethylamine is (1-10): 1-50): 1, preferably (3-8): 6-30): 1.
  10. 10. The method of claim 8, wherein the subsequent separation process comprises a deamination column, a monoethylamine purification column, a diethylamine purification column, a deethanol column, a triethylamine purification column, and a dehydration column.

Description

Ammonolysis catalyst, preparation method thereof and method for preparing monoethylamine Technical Field The invention relates to the technical field of preparation processes of monoethylamine, in particular to an ammonolysis catalyst, a preparation method thereof and a method for preparing monoethylamine. Background Amine refers to a product obtained by substituting one or more hydrogen atoms in an ammonia molecule with hydrocarbon groups, and can be divided into primary amine, secondary amine and tertiary amine according to the number of the hydrogen atoms in the amine molecule, wherein the amine is widely existing in the biological world and has extremely important physiological activity and biological activity, such as protein, nucleic acid, a plurality of hormones, antibiotics, alkaloids and the like, and most of clinically used medicaments are also amine or amine derivatives. Monoethylamine, also known as ethylamine, aminoethane, is a colorless liquid, flammable, and volatile with ammonia odor. The water-soluble polymer is arbitrarily mixed with water, alcohol and ether, is used for preparing dyes, rubber accelerators, extractants, emulsifying agents, pesticides, herbicides and mineral processing agents, is also widely used in the production of dyes, surfactants, antioxidants, preservatives and the like, and can also be used for preparing pesticides simazine, atrazine and the like. At present, the synthesis method of monoethylamine mainly comprises an ethylene ammonification method, a chloroethane ammonification method, an acetonitrile hydrogenation method, an acetaldehyde ammonification method, an ethanol hydro-ammonification method and the like. The reaction process for preparing monoethylamine by ammonolysis of chloroethane has the advantages of by-product hydrogen chloride, low raw material utilization rate, and high generation of chlorine-containing waste water and salt, and serious equipment corrosion and environmental pollution. The acetonitrile hydrogenation reduction method is to prepare monoethylamine by using acetonitrile as raw material and ammonia borane or hydrogen as hydrogen source and liquid phase hydrogenation reduction under the action of metal oxide or Raney nickel and other catalysts. However, acetonitrile is expensive, and has limited use, which makes mass production difficult. Compared with other preparation methods, the ethanol hydro-ammoniation method has the advantages that the ethanol raw material is cheap and easy to obtain, the whole reaction process is relatively safe and environment-friendly, the method has more economical efficiency, and the method is almost adopted to produce ethylamine products in China at present. The catalysts commonly used in the process are supported catalysts such as nickel and cobalt, and the like, and the catalysts are balanced catalysts and have good catalytic reaction performance, so that the hydro-ammoniation process ensures that the proportion of various ethylamine products in the reaction products is relatively fixed, the output proportion is basically 2:5:3, and the proportion of diethylamine is higher. However, the market has different requirements for monoethylamine, diethyl amine and triethylamine, the requirements for monoethylamine and triethylamine are relatively large, and more diethyl amine is produced, and the diethyl amine is required to be separated and then returned to the inlet of the reactor to be mixed with fresh materials and then enters the alcohol ammoniation reactor for a large number of cycles, so that the product proportion is regulated. CN112691677 discloses a catalyst for preparing ethylamine by hydro-ammonifying ethanol and application thereof, and the data of example 14 show that the product contains monoethylamine, diethyl amine and triethylamine, the proportion of diethyl amine is up to more than 50%, and the proportion of monoethylamine is only 17-20%. CN114315593 discloses a method for producing ethylamine with randomly adjustable product proportion, which uses diethylamine produced in the product to further react with ethanol, ammonia and the like to prepare triethylamine, thereby realizing adjustable ethylamine product proportion. However, the method for recycling the diethylamine product in a large quantity greatly improves the whole energy consumption of the device, reduces the production efficiency of the device, and simultaneously generates more byproducts, so that the subsequent separation is difficult, and the economic and environmental protection pressures are increased. Therefore, the development of a method for directly preparing and producing more monoethylamine without recycling a large amount in the existing ethylamine production device has important economic and practical significance. Disclosure of Invention The invention aims to overcome the defect that diethylamine needs to be recycled in a large amount in the prior art, and provides a method for directly preparing and producing more monoethy