Method and apparatus for preparing pentamethylene diisocyanate

Abstract

The present application provides a pentamethylene diamine derivative, a method for purifying a pentamethylene diamine derivative, and a method for using a pentamethylene diamine derivative and phosgene to prepare a pentamethylene diisocyanate by means of a liquid phase method. The present application also provides an apparatus for implementing the methods of the present application.

Description

Method and device for preparing pentamethylene diisocyanate Technical Field

[0001] The present application belongs to the field of chemical engineering, and specifically relates to a pentamethylenediamine derivative, a method for purifying the pentamethylenediamine derivative, and a method for preparing pentamethylene diisocyanate by a liquid phase method using the pentamethylenediamine derivative provided by the present application and phosgene, as well as an apparatus for implementing the method. Background Art

[0002] Isocyanates are a class of compounds containing one or more isocyanate groups, including aliphatic isocyanates, aromatic isocyanates, unsaturated isocyanates, halogenated isocyanates, thioisocyanates, phosphorus-containing isocyanates, inorganic isocyanates, and blocked isocyanates. Due to their highly unsaturated isocyanate groups, they are highly chemically active and can undergo significant chemical reactions with a variety of substances. Consequently, they are widely used in polyurethanes, polyurethaneureas and polyureas, polymer modification, organic synthesis reagents, agriculture, medicine, and other fields.

[0003] The principle of preparing isocyanates using phosgene and amines is well known in the prior art, primarily categorized into liquid-phase and vapor-phase methods. The vapor-phase method involves vaporizing an amine and then reacting it directly with gaseous phosgene to produce the isocyanate. However, since the amine must be vaporized at high temperatures, it is not suitable for heat-sensitive amines. Furthermore, due to the rapid vapor-phase reaction rate, ureas are easily produced as byproducts. A typical liquid-phase method involves three primary chemical reactions: the first reaction is the reaction of the amine with phosgene to form carbamoyl chloride and carbamoyl chloride hydrochloride; the second reaction is the further reaction of carbamoyl chloride hydrochloride with phosgene to form carbamoyl chloride; and the third reaction is the further reaction of carbamoyl chloride to form isocyanate and hydrogen chloride.

[0004] When pentamethylenediisocyanate is produced by the phosgene liquid phase method, pentamethylenediamine (PDA) salt is often prepared by fermentation. Before reacting with phosgene, the PDA salt usually needs to be purified. Common methods for purifying PDA salts include the following: (1) adding an alkaline substance to a PDA salt solution to form a free PDA solution, followed by distillation to obtain PDA (see, for example, CN107043332B). However, this process still needs improvement in terms of handling by-product salts and energy consumption; (2) adding an alkaline substance to a PDA salt solution to form a free PDA solution, using a cationic resin to adsorb PDA, and then eluting the PDA adsorbed on the cationic resin (see, for example, CN108276292B). However, this process is inefficient and has high resin maintenance costs; (3) adding an alkaline substance to a PDA salt solution to form a free PDA solution, and then using an extractant to extract the PDA from the solution. However, this process has high operating costs and a significant impact on the surrounding environment.

[0005] Therefore, there is still a need for new pentamethylenediamine derivatives, optimized purification methods of pentamethylenediamine derivatives, and methods for preparing pentamethylene diisocyanate. Summary of the Invention

[0006] In one aspect, the present application provides a pentamethylenediamine derivative having a chemical formula of H2N(CH2)5NH2CO2, wherein the N atom and the C atom are connected by a covalent bond.

[0007] In certain embodiments, the pentamethylenediamine derivatives provided herein have an amide ester In certain embodiments, the pentamethylenediamine derivatives provided herein have the chemical structure shown below: In certain embodiments, the pentamethylenediamine derivatives provided herein exist in the form of a mixture. In certain embodiments, the pentamethylenediamine derivatives provided herein comprise the following structure: In certain embodiments, in the pentamethylenediamine derivatives provided herein, The total molar amount of The molar amounts are essentially the same.

[0008] In certain embodiments, the pentamethylenediamine derivatives provided herein do not release carbon dioxide at temperatures above 70°C. In certain embodiments, the pentamethylenediamine derivatives provided herein do not release carbon dioxide at temperatures between 70°C and 140°C. In certain embodiments, the pentamethylenediamine derivatives provided herein have a sublimation temperature between 70°C and 140°C.

[0009] In certain embodiments, the chemical bond connection mode of the pentamethylenediamine derivative provided herein in deuterated water solvent and other deuterated solvents is different. In certain embodiments, the nuclear magnetic resonance analysis spectrum of the pentamethylenediamine derivative provided herein after dissolving in the deuterated solvent CD3OD is shown in Figure 1. In certain embodiments, the pentamethylenediamine derivative provided herein after dissolving in the deuterated water solvent (D2O) 1 H-NMR analysis and 13 C-NMR analysis spectra are shown in Figures 2 and 3, respectively. In certain embodiments, the pentamethylenediamine derivatives provided herein are 1 H- 1 H COSY spectrum and 1 H- 13 The C COSY spectra are shown in Figures 4 and 5, respectively.

[0010] In certain embodiments, the pentamethylenediamine derivatives provided herein do not contain carbonate ions (CO3 2- ) or bicarbonate ion (HCO3 - ).

[0011] In another aspect, the present application provides a method for purifying a pentamethylenediamine derivative, wherein the method comprises heating a mixture comprising the pentamethylenediamine derivative described herein to a sublimation temperature of the pentamethylenediamine derivative to obtain a gaseous pentamethylenediamine derivative. In certain embodiments, the sublimation temperature of the pentamethylenediamine derivative is 70° C. to 140° C.

[0012] In certain embodiments, the methods for purifying pentamethylenediamine derivatives provided herein do not include the step of alkalizing the mixture comprising the pentamethylenediamine derivative with an alkaline substance. In certain embodiments, the alkaline substance is selected from the group consisting of sodium hydroxide, potassium hydroxide, aqueous ammonia, calcium hydroxide, magnesium hydroxide, calcium oxide, magnesium oxide, and any combination thereof.

[0013] In certain embodiments, the method for purifying pentamethylenediamine derivatives provided herein further comprises desubliming the obtained gaseous pentamethylenediamine derivatives. In certain embodiments, the desublimation treatment is performed at 30-50°C.

[0014] In certain embodiments, the mixture comprising pentamethylenediamine derivatives is prepared by the following method: introducing carbon dioxide into lysine to form lysine carbonate (bicarbonate), and then reacting the lysine carbonate (bicarbonate) with lysine decarboxylase to generate pentamethylenediamine derivatives.

[0015] In another aspect, the present application provides a method for preparing pentamethylene diisocyanate, wherein the method comprises:

[0016] (a) mixing the pentamethylenediamine derivative described herein or the pentamethylenediamine derivative purified according to the method described herein with a solvent to form a first mixed solution;

[0017] (b) introducing phosgene into the first mixed solution obtained in step (a), adjusting the heating temperature to 100-150° C., and heating for 1-6 hours until the pentamethylenediamine derivative reacts completely and no longer generates hydrogen chloride gas, thereby forming a second solution;

[0018] (c) adjusting the temperature of the second solution obtained in step (b) to 160-180° C. and heating the solution for 6-24 hours until the reaction is complete when no solids are present, stopping the introduction of phosgene, and lowering the temperature to room temperature.

[0019] In certain embodiments, step (b) is replaced by introducing phosgene into the first mixed solution obtained in step (a), adjusting the heating temperature to 70-120°C, and then adding the pentamethylenediamine derivative by flow addition to form a second solution. In certain embodiments, the flow addition lasts for 1-3 hours. In certain embodiments, the flow addition in step (b) is carried out using a screw feeder. In certain embodiments, the flow addition is a uniform flow addition.

[0020] In certain embodiments, the solvent in step (a) is selected from the group consisting of dichloromethane, chlorobenzene, o-dichlorobenzene, benzene, toluene, xylene, hexane, tetrahydrofuran, chloronaphthalene, and any combination thereof. In certain embodiments, the mass ratio of the pentamethylenediamine derivative to the solvent in step (a) is 1:1 to 1:12.

[0021] In some embodiments, the phosgene introduced in step (b) has a flow rate of 0.5 to 5 L / min. In some embodiments, the molar ratio of the phosgene introduced in step (b) to the amino group of the pentamethylenediamine derivative in step (a) is 1.1:1 to 50:1.

[0022] In certain embodiments, the second solution obtained in step (b) contains aminoacyl chloride.

[0023] In certain embodiments, the cooling in step (c) is performed while introducing an inert gas. In certain embodiments, the inert gas is selected from the group consisting of nitrogen, carbon dioxide, carbon monoxide, helium, argon, and any combination thereof. In certain embodiments, the room temperature in step (c) is in the range of -10°C to 40°C.

[0024] In certain embodiments, the method for preparing pentamethylene diisocyanate described herein further comprises step (d): collecting the pentamethylene diisocyanate prepared in step (c).

[0025] In certain embodiments, the present application provides a method for preparing pentamethylene diisocyanate, wherein the method comprises:

[0026] (i) introducing carbon dioxide into the lysine solution to form lysine carbonate (bi) salt, and then reacting the lysine carbonate (bi) salt with lysine decarboxylase to generate a mixture comprising a pentamethylenediamine derivative;

[0027] (ii) heating the mixture comprising the pentamethylenediamine derivative obtained in step (i) to the sublimation temperature of the pentamethylenediamine derivative to obtain a gaseous pentamethylenediamine derivative;

[0028] (iii) The gaseous pentamethylenediamine derivative obtained in step (ii) is subjected to desublimation treatment to obtain a solid pentamethylenediamine derivative;

[0029] (iv) The solid form of the pentamethylenediamine derivative obtained in step (iii) is mixed with a solvent to form a first mixed solution;

[0030] (v) Phosgene is introduced into the first mixed solution obtained in step (iv), and the heating temperature is adjusted to 100 to 150 ° C, and heated for 1 to 6 hours until the pentamethylenediamine derivative reacts completely and no longer produces hydrogen chloride gas to form a second solution;

[0031] (vi) The temperature of the second solution obtained in step (v) is adjusted to above 150 ° C (eg, 160 to 180 ° C), and heated for 6 to 24 hours until the reaction is complete without solid matter, the phosgene is stopped, and the temperature is lowered to room temperature; and

[0032] (vii). Collecting the pentamethylene diisocyanate prepared in step (vi).

[0033] In certain embodiments, step (v) is replaced by introducing phosgene into the first mixed solution obtained in step (iv), adjusting the heating temperature to 70-120° C., and then adding the pentamethylenediamine derivative by flow addition, wherein the flow addition lasts for 1-3 hours to form a second solution.

[0034] In certain embodiments, the lysine decarboxylase in step (i) is purified lysine decarboxylase or is derived from bacteria expressing lysine decarboxylase.

[0035] In another aspect, the present application also provides an apparatus for preparing pentamethylene diisocyanate, wherein the apparatus is used to perform the method for preparing pentamethylene diisocyanate according to the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The above and other features of the present application will be more fully understood through the following description and the appended claims, taken in conjunction with the accompanying drawings. It should be understood that these drawings only depict several embodiments of the present application and, therefore, should not be construed as limiting the scope of the present application. By reference to the accompanying drawings, the present application will be more clearly and fully explained.

[0037] FIG1 shows the nuclear magnetic resonance analysis spectrum of the PDA·CO2 covalent compound described in the present application after being dissolved in deuterated methanol (CD3OD).

[0038] FIG2 shows the PDA·CO2 covalent compound described in this application after being dissolved in deuterated water solvent (D2O). 1 H-NMR analysis spectrum.

[0039] FIG3 shows the PDA·CO2 covalent compound described in this application after being dissolved in deuterated water solvent (D2O). 13 C-NMR analysis spectrum.

[0040] FIG4 shows the PDA·CO2 covalent compound described in this application. 1 H- 1 H COSY spectrum.

[0041] FIG5 shows the PDA·CO2 covalent compound described in this application. 1 H- 13 C COSY spectrum.

[0042] FIG6 and FIG7 show the phenomena observed during the preparation of pentamethylene diisocyanate using a method known in the prior art. DETAILED DESCRIPTION

[0043] The illustrative embodiments described in the detailed description, drawings, and claims are not intended to be limiting. Other embodiments may be employed, and other changes may be made, without departing from the spirit or scope of the subject matter of this application. It is understood that various configurations, substitutions, combinations, and designs of the various aspects of the present disclosure generally described herein and illustrated in the drawings may be made, all of which are expressly incorporated herein as a part of this disclosure.

[0044] Pentamethylenediamine derivatives

[0045] In one aspect, the present application provides a pentamethylenediamine derivative.

[0046] As used herein, the term "derivative" refers to any compound having the same or similar core structure as a compound (also referred to as a parent compound) but having at least one structural difference, including substitution, deletion, and / or addition of one or more atoms or functional groups. For example, a "pentanediamine derivative" refers to any compound having the same or similar core structure as pentamethylenediamine but having at least one structural difference, including substitution, deletion, and / or addition of one or more atoms or functional groups. A "derivative" may include a deuterated, oxidized, dehydrated, unsaturated, polymer-conjugated, or glycosylated form of the parent compound, or an ester, amide, lactone, homolog, ether, thioether, cyano, amino, alkylamino, sulfhydryl, heterocyclic, fused heterocyclic, polymeric, pegylated, benzylidene, triazolyl, piperazinyl, or deuterated form thereof.

[0047] In certain embodiments, the pentamethylenediamine derivatives provided herein have the same core structure as 1,5-pentanediamine (also known as "cadaverine", PDA). (where * is attached to other atoms), but with extra carbon and oxygen atoms.

[0048] In certain embodiments, the pentamethylenediamine derivatives provided herein are covalent compounds formed by pentamethylenediamine and carbon atoms and oxygen atoms, wherein the molar ratio of pentamethylenediamine to carbon atoms other than carbon atoms in pentamethylenediamine and oxygen atoms per molecule of the pentamethylenediamine derivative is 1:1:2. The molar ratio of each atom in the pentamethylenediamine derivative can be determined by methods known in the art, such as elemental analysis and mass spectrometry.

[0049] In certain embodiments, the pentamethylenediamine derivative provided herein is a derivative of 1,5-pentamethylenediamine. In certain embodiments, the pentamethylenediamine derivative provided herein has a chemical formula of H2N(CH2)5NH2CO2 (also referred to as "PDA·CO2" in this application).

[0050] In certain embodiments, the present application provides a pentamethylenediamine derivative having the chemical formula H2N(CH2)5NH2CO2, wherein the nitrogen atom (N atom) and the carbon atom (C atom) are connected by a covalent bond. As used herein, "covalent bond" refers to a chemical bond involving the sharing of electron pairs between atoms, specifically a stable balance of attractive and repulsive forces between atoms when electrons are shared.

[0051] In certain embodiments, the pentamethylenediamine derivatives provided herein have an amide ester In certain embodiments, the pentamethylenediamine derivatives provided herein comprise a zwitterionic structure with an amide ester structure. In certain embodiments, the pentamethylenediamine derivatives provided herein have the chemical structure shown below: In certain embodiments, the pentamethylenediamine derivative provided herein comprises (5-pentammonium)carbamate (ie, (5-azaniumylpentyl)carbamate).

[0052] In certain embodiments, the pentamethylenediamine derivative provided herein has the chemical structure shown below: In certain embodiments, the pentamethylenediamine derivatives provided herein comprise

[0053] In certain embodiments, the pentamethylenediamine derivatives provided herein exist in the form of a mixture. In certain embodiments, the pentamethylenediamine derivatives provided herein exist in the form of a mixture and include In certain embodiments, the pentamethylenediamine derivatives provided herein exist in the form of a mixture and include In certain embodiments, the pentamethylenediamine derivatives provided herein exist in the form of a mixture and include In certain embodiments, the pentamethylenediamine derivatives provided herein exist in the form of a mixture, comprising and The molar amounts are essentially the same.

[0054] "Substantially the same" means that the difference between two or more values ​​does not exceed ±5% (e.g., no more than ±4%, ±3%, ±2%, ±1%, ±0.5%, ±0.1%, etc.). For example, when referring to "substantially the same in molar amount," it means that the difference between the molar amounts does not exceed ±5% (e.g., no more than ±4%, ±3%, ±2%, ±1%, ±0.5%, ±0.1%, etc.).

[0055] In certain embodiments, the pentamethylenediamine derivatives provided herein exist in the form of a mixture, comprising and The molar amounts are the same.

[0056] In certain embodiments, the pentamethylenediamine derivative provided herein comprises the following structure: In certain embodiments, the pentamethylenediamine derivatives provided herein are composition.

[0057] In certain embodiments, the pentamethylenediamine derivatives provided herein comprise in The total molar amount of In certain embodiments, the pentamethylenediamine derivatives provided herein comprise in The total molar amount of The molar amounts are the same.

[0058] In certain embodiments, the pentamethylenediamine derivatives provided herein comprise in The molar amounts of The molar amounts are essentially the same.

[0059] In certain embodiments, the pentamethylenediamine derivatives provided herein comprise in The molar amounts of In certain embodiments, the pentamethylenediamine derivatives provided herein comprise And the molar ratio of the three is 2:1:1.

[0060] In certain embodiments, the pentamethylenediamine derivatives provided herein are Composition, of which The molar amounts of In certain embodiments, the pentamethylenediamine derivatives provided herein are composed of The molar ratio of the three is 2:1:1.

[0061] In certain embodiments, the pentamethylenediamine derivatives provided herein do not release carbon dioxide at temperatures above 70°C. In certain embodiments, the pentamethylenediamine derivatives provided herein sublime at temperatures above 70°C (e.g., 70-200°C) to form gaseous pentamethylenediamine derivatives, but do not decompose. In certain embodiments, the pentamethylenediamine derivatives provided herein do not release carbon dioxide at temperatures between 70°C and 200°C (e.g., 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, or any value between any two of the above ranges). In certain embodiments, the pentamethylenediamine derivatives provided herein do not release carbon dioxide at temperatures between 70°C and 140°C. In certain embodiments, the pentamethylenediamine derivatives provided herein have a sublimation temperature of 70°C to 140°C (e.g., 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, or any specific temperature between any two of the above numerical ranges). In certain embodiments, the pentamethylenediamine derivatives provided herein have an increased density and / or hardness after sublimation.

[0062] In certain embodiments, the chemical bonding patterns of the pentamethylenediamine derivatives provided herein differ in deuterated water and other deuterated solvents (e.g., deuterated chloroform, deuterated methanol, etc.). The chemical bonding patterns of the pentamethylenediamine derivatives provided herein in deuterated solvents can be determined using methods commonly used in the art (e.g., nuclear magnetic resonance analysis). The inventors of this application have discovered that when nuclear magnetic resonance analysis of the same sample of the pentamethylenediamine derivatives provided herein is performed using different deuterated solvents, the resulting nuclear magnetic resonance characterization information is different, indicating that the solvent affects the structural changes of the sample.

[0063] In certain embodiments, the NMR analysis spectrum of the pentamethylenediamine derivative provided by the present application after being dissolved in deuterated methanol (CD3OD) is shown in Figure 1. In certain embodiments, the NMR analysis spectrum of the pentamethylenediamine derivative provided by the present application after being dissolved in deuterated water solvent (D2O) is shown in Figure 1. 1 The H-NMR analysis spectrum is shown in Figure 2. In certain embodiments, the pentamethylenediamine derivative provided by the present application is dissolved in a deuterated water solvent (D2O). 13 C-NMR analysis spectrum is shown in Figure 3. In certain embodiments, the pentamethylenediamine derivatives provided herein are 1 H- 1 H chemical shift correlation spectroscopy ( 1 H- 1 H COSY spectrum) is shown in Figure 4. In certain embodiments, the pentamethylenediamine derivatives provided herein are 1 H- 13 C chemical shift correlation spectroscopy ( 1 H- 13 C COSY spectrum) is shown in Figure 5.

[0064] In certain embodiments, the pentamethylenediamine derivatives provided herein do not contain carbonate ions (CO3 2- In certain embodiments, the pentamethylenediamine derivatives provided herein do not contain bicarbonate ions (HCO3 - In certain embodiments, the pentamethylenediamine derivatives provided herein do not contain carbonate ions (CO3 2- ) and bicarbonate ions (HCO3 - In certain embodiments, the pentamethylenediamine derivative provided herein is a PDA·CO2 covalent compound.

[0065] Method for purifying pentamethylenediamine derivatives

[0066] In one aspect, the present application provides a method for purifying a pentamethylenediamine derivative, wherein the method comprises heating a mixture containing the pentamethylenediamine derivative described herein to the sublimation temperature of the pentamethylenediamine derivative to obtain a gaseous pentamethylenediamine derivative. All contents described in the "Pentamethylenediamine Derivatives" section of this application also apply to the description of the pentamethylenediamine derivative purification method in this section and are therefore not further elaborated.

[0067] In the present application, the "mixture containing a pentamethylenediamine derivative" contains, in addition to the pentamethylenediamine derivative, impurities such as salts, sugars, and bacteria other than the pentamethylenediamine derivative.

[0068] In certain embodiments, the pentamethylenediamine derivative in the mixture has a purity of 80% or greater (e.g., 85% or greater, 86% or greater, 87% or greater, 88% or greater, 89% or greater, 90% or greater, 91% or greater, 92% or greater, 93% or greater, 94% or greater, 95% or greater, or 96% or greater). The inventors of the present application unexpectedly discovered that a gaseous pentamethylenediamine derivative of higher purity can be obtained by heating the mixture containing the pentamethylenediamine derivative described herein to a certain temperature to cause the pentamethylenediamine derivative to sublime. The obtained higher-purity pentamethylenediamine derivative can then react with phosgene to prepare pentamethylene diisocyanate. The purity of the gaseous pentamethylenediamine derivative obtained by this method can reach 98% or greater, thus meeting the requirements of large-scale industrial production.

[0069] The mixture containing the pentamethylenediamine derivative can be sublimed using methods common in the art. For example, the mixture containing the pentamethylenediamine derivative can be heated by controlling parameters such as temperature and air pressure so that the pentamethylenediamine derivative is converted into a gaseous state while the impurities remain in the mixture. For another example, the mixture containing the pentamethylenediamine derivative can be heated using a commercial purification device (e.g., a flash evaporation device) so that the pentamethylenediamine derivative is converted into a gaseous state while the impurities remain in the mixture. In certain embodiments, the heating temperature is controlled to a temperature at which the pentamethylenediamine derivative sublimes but does not decompose. Without being limited by any theory, it is preferred to control the heating temperature to a temperature at which the pentamethylenediamine derivative sublimes but does not decompose because this setting can ensure that the purity of the obtained gaseous pentamethylenediamine derivative is sufficiently high and that the yield of the pentamethylenediamine derivative after purification is sufficiently high.

[0070] In certain embodiments, the sublimation temperature of the pentamethylenediamine derivative is 70-140°C (e.g., 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, or any specific temperature between any two numerical ranges above). In certain embodiments, the mixture comprising the pentamethylenediamine derivative is heated to 70-140°C (e.g., 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, or any specific temperature between any two numerical ranges above).

[0071] In certain embodiments, the mixture containing the pentamethylenediamine derivative is heated in a heater having a heating medium. The heating medium can be any heating medium known in the art. In certain embodiments, the heating medium is selected from the group consisting of an inorganic superconducting heat transfer medium, a composite heat-conducting fiber medium, a graphite heat-conducting medium, a carbon fiber heat-conducting medium, thermal oil, high-pressure steam, or molten salt. In certain embodiments, the heating medium is thermal oil. In certain embodiments, the thermal oil is selected from one or more of the group consisting of alkylnaphthalene, alkylbenzene, dibenzyltoluene, and hydrogenated terphenyl. In certain embodiments, the thermal oil is heated to a temperature at or above the sublimation temperature of the pentamethylenediamine derivative. For example, the heat transfer oil allows the heating temperature to reach or exceed 70-140°C (for example, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C or any specific temperature between any two numerical ranges above).

[0072] In certain embodiments, the outer surface of the inner tube of the heater is coated with a heat-conducting metal, such as aluminum, copper, silver, aluminum alloy, copper alloy, silver alloy, etc. Coating the outer surface of the inner tube of the heater with a heat-conducting metal can further save energy, thereby reducing energy consumption and saving costs.

[0073] Without being bound by any theory, it is believed that a preheating step prior to sublimation of the pentamethylenediamine derivative is particularly preferred in the pentamethylenediamine derivative purification method described herein. For example, prior to sublimation of the pentamethylenediamine derivative, the mixture containing the pentamethylenediamine derivative can be preheated to, for example, 100-140° C. (e.g., 100° C., 105° C., 110° C., 115° C., 120° C., 125° C., 130° C., 135° C., 140° C., or any specific temperature between any two of the above numerical ranges).

[0074] In certain embodiments, the method for purifying pentamethylenediamine derivatives provided herein comprises flash-subliming the preheated pentamethylenediamine derivatives in a separator to form gaseous pentamethylenediamine derivatives.

[0075] In certain embodiments, the method for purifying pentamethylenediamine derivatives provided herein further comprises desubliming the obtained gaseous pentamethylenediamine derivative. Without being bound by any theory, it is believed that the lower the desublimation temperature, the more favorable the desublimation of the gaseous pentamethylenediamine derivative. In certain embodiments, the obtained gaseous pentamethylenediamine derivative is desublimed at 30-50°C (e.g., 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C, 50°C, or any specific temperature between any two of the above numerical ranges).

[0076] In certain embodiments, the present application provides a method for purifying a PDA·CO2 covalent compound, wherein the method comprises: preheating a mixture containing the PDA·CO2 covalent compound to a temperature close to or equal to the sublimation temperature of the PDA·CO2 covalent compound; and separating the preheated PDA·CO2 covalent compound at the sublimation temperature of the PDA·CO2 covalent compound. In certain embodiments, the sublimation temperature of the PDA·CO2 covalent compound is 70 to 140°C (e.g., 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, or any specific temperature between any two numerical ranges above). In certain embodiments, the obtained gaseous PDA·CO2 covalent compound is subjected to a desublimation treatment. In certain embodiments, the obtained gaseous PDA·CO2 covalent compound is desublimated at 30-50°C (e.g., 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C, 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C, 50°C or any specific temperature between any two numerical ranges).

[0077] In certain embodiments, the method for purifying pentamethylenediamine derivatives provided herein does not include the step of alkalizing the mixture containing pentamethylenediamine derivatives using an alkaline substance (e.g., sodium hydroxide, potassium hydroxide, ammonia water, calcium hydroxide, magnesium hydroxide, calcium oxide, magnesium oxide, or any combination thereof). In conventional methods for preparing pentamethylenediamine diisocyanate, the mixture of pentamethylenediamine derivatives is desalted by the alkalization treatment and then converted into free pentamethylenediamine, which is then subjected to a subsequent phosgenation reaction to generate pentamethylenediamine diisocyanate. In the method of the present application, the pentamethylenediamine derivatives do not need to be converted into free amines by alkalization treatment. Instead, the pentamethylenediamine derivatives are directly purified to obtain purified pentamethylenediamine derivatives, which are then directly subjected to a phosgenation reaction. The method of directly purifying pentamethylenediamine derivatives of the present invention not only avoids the desalting step, reducing corrosion to equipment and investment costs, but also avoids the operational steps of separating free amines and water, greatly simplifying the process and reducing energy consumption.

[0078] In addition, the pentamethylenediamine derivative purified by the method provided in this application contains substantially no volatile organic compounds (VOCs). Pentamethylenediamine diisocyanate prepared by reacting the purified pentamethylenediamine derivative with phosgene also contains substantially no VOCs.

[0079] The mixture comprising pentamethylenediamine derivatives can be prepared using any method known in the art. In certain embodiments, the mixture comprising pentamethylenediamine derivatives is prepared by an enzyme-catalyzed method. In certain embodiments, the mixture comprising pentamethylenediamine derivatives is prepared by introducing carbon dioxide into a lysine solution to form lysine carbonate (bicarbonate), and then reacting the lysine carbonate (bicarbonate) with lysine decarboxylase to produce the pentamethylenediamine derivative.

[0080] In certain embodiments, carbon dioxide is introduced into the lysine solution until the pH reaches 7-8 (e.g., 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8.0, or any specific pH value within a range between any two of the above values), and then the supply of carbon dioxide is stopped.

[0081] In certain embodiments, the concentration of the lysine carbonate (bicarbonate) solution formed is 200 g / L to 650 g / L, for example, 210 g / L, 220 g / L, 230 g / L, 240 g / L, 250 g / L, 260 g / L, 270 g / L, 280 g / L, 285 g / L, 290 g / L, 300 g / L, 350 g / L, 400 g / L, 4 50g / L, 500g / L, 510g / L, 520g / L, 530g / L, 540g / L, 550g / L, 560g / L, 570g / L, 580g / L, 590g / L, 600g / L, 610g / L, 620g / L, 630g / L, 640g / L, 650g / L, or any specific concentration in a range between any two of the above values.

[0082] In certain embodiments, the lysine decarboxylase is a purified lysine decarboxylase. In certain embodiments, the lysine decarboxylase is derived from thalli expressing lysine decarboxylase. In certain embodiments, the thalli comprises wet thalli, a broken thalli solution, or immobilized thalli. In certain embodiments, the thalli is derived from recombinant engineered bacteria. In certain embodiments, the lysine decarboxylase is derived from recombinant engineered Escherichia coli bacteria expressing lysine decarboxylase. In certain embodiments, the lysine decarboxylase is derived from wet thalli of recombinant engineered Escherichia coli bacteria expressing lysine decarboxylase. In certain embodiments, the lysine decarboxylase is derived from a broken thalli of recombinant engineered Escherichia coli bacteria expressing lysine decarboxylase. In certain embodiments, the lysine decarboxylase is derived from immobilized thalli of recombinant engineered Escherichia coli bacteria expressing lysine decarboxylase.

[0083] In certain embodiments, the lysine (bi)carbonate reacts with lysine decarboxylase at a temperature of 20-40°C (e.g., 20°C, 25°C, 30°C, 31°C, 32°C, 33°C, 34°C, 35°C, 36°C, 37°C, 38°C, 39°C, 40°C or any specific temperature in the range between any two of the above values) to produce a pentamethylenediamine derivative.

[0084] In certain embodiments, the reaction time of lysine carbonate (bicarbonate) and lysine decarboxylase is 5 to 15 hours (e.g., 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours or any specific time within the range between any two of the above values).

[0085] In certain embodiments, when lysine content<0.5% (w / v), for example, 0.4%, 0.3%, 0.2%, 0.1% or even lower, it indicates that the catalytic reaction of lysine carbonate (bi) salt and lysine decarboxylase ends. Those skilled in the art can adopt the conventional means of this area to measure lysine content, for example, HPLC method.

[0086] In some embodiments, after the catalytic reaction of lysine carbonate (bi) salt and lysine decarboxylase ends, further comprising removing the residue in the reaction solution. In some embodiments, the residue comprises large particle impurities, such as impurities such as cells, bacterial fragments, aggregates, and flocculent bodies, and also comprises small molecule impurities, such as impurities such as nucleic acids and nucleic acid fragments, proteins, and culture medium components in bacterial culture. Those skilled in the art can use conventional separation means to remove the residue of the catalyst described in the mixture according to their actual needs, such as, one or more of the various means such as filtration, centrifugation, microfiltration, and ultrafiltration.

[0087] In certain embodiments, the filtration is achieved by using filter paper or filter cloth. The filter paper or filter cloth described in the present invention can be commercially available filter paper or filter cloth, such as filter paper or filter cloth produced by companies such as GE Healthcare Life Sciences, Shi Bichun, Asahi Chemical Corporation. In certain embodiments, the pore size of the filter paper or filter cloth is 10 to 150 μm, such as 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm or any value between any two of the above numerical ranges. Those skilled in the art can select a suitable filter paper or filter cloth pore size to remove impurities according to the size of the impurities.

[0088] In certain embodiments, the microfiltration is achieved by passing the reaction solution through a microfiltration membrane. The microfiltration membrane described in the present invention can be a commercially available microfiltration membrane, such as the microfiltration hollow fiber membrane series produced by GE Healthcare Life Sciences, Shi Bichun, Asahi Chemical Corporation, etc. In certain embodiments, the pore size of the microfiltration membrane is 0.1μm to 0.6μm, such as 0.1μm, 0.15μm, 0.2μm, 0.22μm, 0.25μm, 0.3μm, 0.35μm, 0.4μm, 0.45μm, 0.5μm, 0.55μm, 0.6μm or any value between any two of the above numerical ranges. Those skilled in the art can select a suitable microfiltration membrane pore size to remove impurities according to the size of the impurities.

[0089] In certain embodiments, the ultrafiltration is achieved by passing the reaction solution through an ultrafiltration membrane. The ultrafiltration membrane described in the present invention can be a commercially available ultrafiltration membrane, such as the ultrafiltration hollow fiber membrane series produced by GE Healthcare Life Sciences, Shi Bichun Company, Asahi Chemical Industry Co., Ltd., etc. In certain embodiments, the ultrafiltration membrane is a hollow fiber ultrafiltration membrane with a pore size of 5kD to 500kD, such as a hollow fiber ultrafiltration membrane with a pore size of 5kD, 6kD, 7kD, 8kD, 9kD, 10kD, 20kD, 30kD, 40kD, 50kD, 60kD, 70kD, 80kD, 90kD, 100kD, 150kD, 200kD, 250kD, 300kD, 350kD, 400kD, 450kD, 500kD or any value between any two numerical ranges above. Those skilled in the art can select a suitable ultrafiltration membrane pore size to remove impurities according to the size of the impurities.

[0090] In certain embodiments, the method further comprises concentrating the prepared pentamethylenediamine derivative. In certain embodiments, the concentration is achieved by reducing pressure. For example, the reaction solution after filtration, microfiltration, or ultrafiltration is pumped into a concentration device for concentration under reduced pressure to 1 / 3, 1 / 4, 1 / 5, 1 / 6, 1 / 7, 1 / 8, 1 / 9, 1 / 10 of the original volume, or any value between any two of the above values.

[0091] In certain embodiments, the process further comprises crystallizing the prepared pentamethylenediamine derivative. In certain embodiments, the crystallization is achieved by lowering the temperature and adding an organic solvent (e.g., methanol, ethanol, isopropanol, etc.). For example, 1, 2, 3, or 4 times the volume of the organic solvent is added dropwise to the concentrated reaction solution, and crystallization is carried out under low temperature conditions (e.g., 10°C, 5°C, or lower). In certain embodiments, the crystallization is carried out by vacuum drying. For example, the prepared pentamethylenediamine derivative is dried in a vacuum oven at 50-70°C (e.g., 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C, 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C, 70°C, or any specific temperature between any two specific numerical ranges above) to obtain the pentamethylenediamine derivative.

[0092] In certain embodiments, a lysine carbonate (bicarbonate) solution having a concentration of 500 g / L to 650 g / L (e.g., 500 g / L, 510 g / L, 520 g / L, 530 g / L, 540 g / L, 550 g / L, 560 g / L, 570 g / L, 580 g / L, 590 g / L, 600 g / L, 610 g / L, 620 g / L, 630 g / L, 640 g / L, 650 g / L or any specific concentration within the range between any two values) is prepared, and then the prepared lysine carbonate (bicarbonate) solution is added to the prepared lysine carbonate solution. Wet cells of an engineered Escherichia coli bacterium containing lysine decarboxylase are added to a lysine carbonate (bicarbonate) solution and subjected to an enzymatic reaction for 8 to 12 hours (e.g., 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, or any specific time within a range between any two of the above values). The reaction temperature is controlled at 35 to 40° C. (e.g., 35° C., 36° C., 37° C., 38° C., 39° C., 40° C., or any specific temperature within a range between any two of the above values). The reaction is terminated when the lysine content measured by HPLC is less than 0.5% (w / v). The residue in the reaction solution is then removed and the product is dried in a vacuum oven at 50 to 70° C. to obtain a crude pentamethylenediamine derivative.

[0093] In certain embodiments, a 600 g / L lysine carbonate (bicarbonate) solution is prepared, and wet cells of engineered Escherichia coli bacteria containing lysine decarboxylase are added to the prepared lysine carbonate (bicarbonate) solution for an enzymatic reaction for 10 hours. The reaction temperature is controlled at 37°C, and the reaction is terminated when the lysine content measured by HPLC is less than 0.5% (w / v). The residue in the reaction solution is then removed, and the product is dried in a vacuum oven at 50-70°C to obtain a crude pentamethylenediamine derivative.

[0094] The mixture comprising the pentamethylenediamine derivative can be in any suitable state. In certain embodiments, the mixture comprising the pentamethylenediamine derivative is in a solid state. In certain embodiments, the mixture comprising the pentamethylenediamine derivative is in a powdered state. Without being limited by theory, it is believed that a powdered mixture is more conducive to the purification of the pentamethylenediamine derivative.

[0095] Method for preparing pentamethylene diisocyanate

[0096] In another aspect, the present application also provides a method for preparing pentamethylene diisocyanate, wherein the method comprises:

[0097] (a) mixing the pentamethylenediamine derivative provided herein or the pentamethylenediamine derivative purified according to the method described herein with a solvent to form a first mixed solution;

[0098] (b) introducing phosgene into the first mixed solution obtained in step (a), adjusting the heating temperature to 100-150° C., and heating for 1-6 hours until the pentamethylenediamine derivative reacts completely and no longer generates hydrogen chloride gas, thereby forming a second solution;

[0099] (c) adjusting the temperature of the second solution obtained in step (b) to 160-180° C. and heating the solution at this temperature for 6-24 hours, or until the second solution becomes clear and free of solid matter, and then stopping the introduction of phosgene and lowering the temperature to room temperature.

[0100] In certain embodiments, the method for preparing pentamethylene diisocyanate provided herein further comprises step (d): collecting the pentamethylene diisocyanate prepared in step (c). In certain embodiments, the pentamethylene diisocyanate prepared by the method described herein is 1,5-pentamethylene diisocyanate.

[0101] The following describes in detail step (a), step (b), step (c), and optional step (d) of the method for preparing pentamethylene diisocyanate described in the present application.

[0102] Step (a)

[0103] In the method for preparing pentamethylene diisocyanate provided herein, step (a) comprises mixing the pentamethylenediamine derivative provided herein, or the pentamethylenediamine derivative purified according to the method described herein, with a solvent to form a first mixed solution. All contents described in the "Method for Purifying Pentamethylenediamine Derivatives" section of this application also apply to the description of the method for preparing pentamethylene diisocyanate in this section and are therefore not further elaborated here.

[0104] In certain embodiments, a pentamethylenediamine derivative provided herein or purified according to the methods described herein is mixed with a solvent to form a first mixed solution, wherein the solvent is selected from the group consisting of dichloromethane, chlorobenzene, o-dichlorobenzene, benzene, toluene, xylene, hexane, tetrahydrofuran, chloronaphthalene, and any combination thereof. In the present application, the preferred solvent for the pentamethylenediamine derivative is o-dichlorobenzene or chlorobenzene.

[0105] In certain embodiments, the mass ratio of the pentamethylenediamine derivative to the solvent in step (a) is 1:1 to 1:20 (e.g., 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19, 1:20, or any specific ratio between any two of the above specific ratio ranges). In certain embodiments, the mass ratio of the pentamethylenediamine derivative to the solvent in step (a) is 1:1 to 1:12. In certain embodiments, the mass ratio of the pentamethylenediamine derivative to the solvent in step (a) is 1:10.

[0106] In certain embodiments, the pentamethylenediamine derivative and the solvent in step (a) are mixed at a temperature of 20 to 50° C. (e.g., 20° C., 25° C., 30° C., 35° C., 40° C., 45° C., 50° C., or any specific temperature within a range between any two of the above values).

[0107] In certain embodiments, step (a) comprises mixing the PDA·CO2 covalent compound with a solvent (e.g., dichloromethane, chlorobenzene, o-dichlorobenzene, benzene, toluene, xylene, hexane, tetrahydrofuran, chloronaphthalene, and any combination thereof) to form a first mixed solution. In certain embodiments, step (a) comprises mixing the PDA·CO2 covalent compound with o-dichlorobenzene to form a first mixed solution. In certain embodiments, step (a) comprises mixing a PDA·CO2 covalent compound with o-dichlorobenzene to form a first mixed solution, wherein the mass ratio of the PDA·CO2 covalent compound to o-dichlorobenzene is 1:1 to 1:20 (e.g., 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19, 1:20, or any specific ratio between any two of the above specific ratio ranges). In certain embodiments, step (a) comprises mixing a PDA·CO2 covalent compound with o-dichlorobenzene to form a first mixed solution, wherein the mass ratio of the PDA·CO2 covalent compound to o-dichlorobenzene is 1:1 to 1:12. In certain embodiments, step (a) comprises mixing the PDA·CO2 covalent compound with o-dichlorobenzene to form a first mixed solution, wherein the mass ratio of the PDA·CO2 covalent compound to o-dichlorobenzene is 1:10. In certain embodiments, step (a) comprises mixing 20 g of the PDA·CO2 covalent compound with 200 g of o-dichlorobenzene to form the first mixed solution.

[0108] Step (b)

[0109] In the method for preparing pentamethylene diisocyanate provided in the present application, step (b) comprises introducing phosgene into the first mixed solution obtained in step (a), adjusting the heating temperature to 100-150° C., and heating for 1-6 hours until the pentamethylenediamine derivative reacts completely and no longer produces hydrogen chloride gas, thereby forming a second solution.

[0110] During the preparation of pentamethylene diisocyanate, a large excess of phosgene is often required. This is because when the phosgene concentration is insufficient, the formed pentamethylene diisocyanate reacts with excess amine to form urea or other highly viscous solid byproducts. Therefore, to prevent the formation of byproducts, phosgene is preferably provided in excess. For example, in certain embodiments, the phosgene introduced into the first mixed solution obtained in step (a) in step (b) is in stoichiometric excess based on the amino groups of the pentamethylenediamine derivative. For example, the molar ratio of phosgene to the amino groups of the pentamethylenediamine derivative is typically 1.1:1-50:1 (e.g., 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 7.5:1, 8:1, 8.5:1, 9:1, 9.5:1, 10:1, 11:1, 15:1, 20:1, 25:1, 30:1, 35:1, 40:1, 45:1, 50:1, and ranges therebetween). In certain embodiments, phosgene is used in a stoichiometric excess of 0% to 250% (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, 110%, 120%, 130%, 140%, 150%, 160%, 170%, 180%, 190%, 200%, 210%, 220%, 230%, 240%, 250%, etc.) of the theoretical amount based on the amino group of the pentamethylenediamine derivative.

[0111] In certain embodiments, the ratio of phosgene in step (b) to the pentamethylenediamine derivative in the first mixed solution (by mole) is 7:1 to 25:1 (e.g., 8:1, 9:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1, 20:1, 21:1, 22:1, 23:1, 24:1, 25:1, or any number between any two of the above ratios). Preferably, the ratio of phosgene in step (b) to the pentamethylenediamine derivative in the first mixed solution (by mole) is 8:1 to 20:1. In certain embodiments, the ratio of phosgene in step (a) to the pentamethylenediamine derivative in the first mixed solution (by mole) is 8:1.

[0112] The delivery rate of phosgene can be controlled by adjusting a flow meter, a valve, etc. In certain embodiments, the phosgene flow rate introduced in step (b) is 0.5 to 5 L / min (e.g., 0.5 L / min, 0.6 L / min, 0.7 L / min, 0.8 L / min, 0.9 L / min, 1 L / min, 1.1 L / min, 1.2 L / min, 1.3 L / min, 1.4 L / min, 1.5 L / min, 1.6 L / min, 1.7 L / min, 1.8 L / min, 1.9 L / min, 2 L / min, 2.5 L / min, 3 L / min, 3.5 L / min, 4 L / min, 4.5 L / min, 5 L / min or any specific value between any two numerical ranges). In certain embodiments, the phosgene flow rate introduced in step (b) is 1.2 L / min.

[0113] The phosgene described in step (b) can be fresh phosgene or recycled phosgene. The term "fresh phosgene" refers to a phosgene-containing stream that has not been recycled from the phosgenation process and has not yet undergone any reaction stage involving a phosgene reaction after phosgene is synthesized from chlorine and carbon monoxide. The term "recycled phosgene" refers to a phosgene-containing stream collected from the tail gas during the reaction process of preparing pentamethylene diisocyanate by the phosgenation process. As mentioned above, in the process of preparing pentamethylene diisocyanate by the liquid phase method, it is often necessary to use excess phosgene, so the reaction tail gas will contain a large amount of phosgene. Recycling the phosgene in the tail gas can achieve the purpose of reducing production costs. In certain embodiments, the phosgene described in step (b) exists in liquid form.

[0114] In certain embodiments, the first mixed liquid and phosgene described in step (b) are reacted at any temperature between 100 and 150°C, for example, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C or any value between any two of the above values. In certain embodiments, the first mixed liquid and phosgene described in step (b) are reacted at any temperature between 110 and 140°C. In certain embodiments, the reaction can be carried out at any constant temperature between 100 and 150°C, or at a variable temperature between 100 and 150°C. In certain embodiments, the reaction can be carried out at any constant temperature between 110 and 140°C, or at a variable temperature between 110 and 140°C.

[0115] In certain embodiments, the phosgene is stored in a gas storage tank before entering the first mixed liquid, and the pressure of the gas storage tank is maintained at 0.05-0.1 MPa (e.g., 0.06 MPa, 0.07 MPa, 0.08 MPa, 0.09 MPa, 0.1 MPa, etc.).

[0116] In certain embodiments, the phosgene is pressurized and then reacted with the first mixed solution, for example, to a pressure between 0.1 MPa and 0.7 MPa (for example, 0.15 MPa, 0.16 MPa, 0.17 MPa, 0.18 MPa, 0.19 MPa, 0.2 MPa, 0.21 MPa, 0.22 MPa, 0.23 MPa, 0.24 MPa, 0.25 MPa, 0.26 MPa, 0.27 MPa, 0.28 MPa, 0.29 MPa, 0.3 MPa, 0.31 MPa, 0.32 MPa, 0.33 MPa, 0.34 MPa, 0.35 MPa, 0.4 MPa, 0.45 MPa, 0.5 MPa, 0.55 MPa, 0.6 MPa, 0.65 MPa, 0.7 MPa or any value within a range between any two of the above values).

[0117] In certain embodiments, phosgene is introduced into the first mixed solution obtained in step (a), the heating temperature is adjusted to 100-150°C, and the mixture is heated at this temperature until the pentamethylenediamine derivative is completely reacted and no more hydrogen chloride gas is produced, thereby forming a second solution. In certain embodiments, phosgene is introduced into the first mixed solution obtained in step (a), the heating temperature is adjusted to 100-150°C, and the mixture is heated at this temperature for 1-6 hours (e.g., 1, 2, 3, 4, 5, 6 hours, or any number within a range between any two of these values), until the pentamethylenediamine derivative is completely reacted and no more hydrogen chloride gas is produced, thereby forming a second solution.

[0118] In certain embodiments, step (b) is replaced by passing phosgene into the first mixed solution obtained in step (a), adjusting the heating temperature to 70-120°C (e.g., 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, or any value between any two of the above values), and then adding the pentamethylenediamine derivative by stream addition to form a second solution. In certain embodiments, step (b) is replaced by passing phosgene into the first mixed solution obtained in step (a), adjusting the heating temperature to 80-100°C, and then adding the pentamethylenediamine derivative by stream addition to form a second solution. In certain embodiments, the duration of the stream addition is 1-3 hours (e.g., 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, or any value between any two of the above values). In certain embodiments, the duration of the stream addition is 2 hours.

[0119] Without being bound by any theory, it is believed that it is particularly beneficial to add the pentamethylenediamine derivative in an additional manner by stream addition. For example, in this case, the pentamethylenediamine derivative in the first mixed solution described in step (a) can be a small amount, thereby reducing the amount of solvent used, saving costs and reducing the pollution of the solvent to the environment. Moreover, stream addition of the pentamethylenediamine derivative can avoid the situation where the amine excess at the beginning of the reaction causes the reaction to be too violent and may cause the material to overflow, while also reducing the by-product ratio and stabilizing the phosgene unit time consumption. The pentamethylenediamine derivative can be streamed in a variety of ways, for example, by a screw feed device. The pentamethylenediamine derivative added in stream can be in solid form or in a liquid form dissolved in a solvent (for example, o-dichlorobenzene, etc.). In some embodiments, the pentamethylenediamine derivative and the solvent form a high concentration dispersible solvent, which is then streamed in liquid form. In some embodiments, it is preferred to stream add the pentamethylenediamine derivative at a uniform rate because the reaction rate of the pentamethylenediamine derivative and phosgene can be better controlled in this way, thereby improving the yield and reducing the generation of by-products.

[0120] In certain embodiments, step (b) involves the first-stage reaction of preparing pentamethylene diisocyanate using a phosgene liquid phase process, i.e., the reaction of a pentamethylenediamine derivative with phosgene to produce aminoacyl chloride and hydrogen chloride gas. In certain embodiments, the second solution obtained in step (b) contains aminoacyl chloride. In certain embodiments, the second solution obtained in step (b) is a mixed solution of aminoacyl chloride and the solvent (e.g., o-dichlorobenzene).

[0121] Step (c)

[0122] In the method for preparing pentamethylene diisocyanate provided in the present application, step (c) includes adjusting the temperature of the second solution obtained in step (b) to 160-180° C. and heating it for 6-24 hours until the reaction is completed when there is no solid matter, stopping the introduction of phosgene, and lowering the temperature to room temperature.

[0123] In certain embodiments, step (c) comprises adjusting the temperature of the second solution obtained in step (b) to 160° C., 161° C., 162° C., 163° C., 164° C., 165° C., 166° C., 167° C., 168° C., 169° C., 170° C., 171° C., 172° C., 173° C., 174° C., 175° C., 176° C., 177° C., 178° C., 179° C., 180° C., or any value within a range between any two of the above values. In certain embodiments, step (c) is a second-stage reaction of preparing pentamethylene diisocyanate using a phosgene liquid phase process, i.e., the aminoacyl chloride produced in step (b) further reacts with phosgene to produce pentamethylene diisocyanate and hydrogen chloride gas.

[0124] In certain embodiments, step (c) comprises adjusting the temperature of the second solution obtained in step (b) to 160-180° C. and heating the solution for 6-24 hours, for example, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, 24 hours or any value between any two of the above ranges.

[0125] In certain embodiments, an inert gas is introduced during the cooling process in step (c). In certain embodiments, the inert gas is selected from the group consisting of nitrogen, carbon dioxide, carbon monoxide, helium, argon, and any combination thereof. In certain embodiments, the room temperature in step (c) is in the range of -10°C to 40°C, for example, -10°C, -5°C, 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, or any value in the range between any two of the above values.

[0126] In certain embodiments, the present application provides a method for preparing pentamethylene diisocyanate, wherein the method comprises:

[0127] (i) introducing carbon dioxide into the lysine solution to form lysine carbonate (bi) salt, and then reacting the lysine carbonate (bi) salt with lysine decarboxylase to generate a mixture comprising a pentamethylenediamine derivative;

[0128] (ii) heating the mixture comprising the pentamethylenediamine derivative obtained in step (i) to the sublimation temperature of the pentamethylenediamine derivative to obtain a gaseous pentamethylenediamine derivative;

[0129] (iii) The gaseous pentamethylenediamine derivative obtained in step (ii) is subjected to desublimation treatment to obtain a solid pentamethylenediamine derivative;

[0130] (iv) The solid form of the pentamethylenediamine derivative obtained in step (iii) is mixed with a solvent to form a first mixed solution;

[0131] (v) adding phosgene to the first mixed solution obtained in step (iv), adjusting the heating temperature to 100-150° C. (e.g., 100° C., 105° C., 110° C., 115° C., 120° C., 125° C., 130° C., 135° C., 140° C., 145° C., 150° C., or any value between any two of the above values), and heating for 1-6 hours (e.g., 1, 2, 3, 4, 5, 6 hours, or any value within a range between any two of the above values), until the pentamethylenediamine derivative reacts completely and no longer produces hydrogen chloride gas, thereby forming a second solution;

[0132] (vi) adjusting the temperature of the second solution obtained in step (v) to above 150°C (e.g., 160-180°C, for example, 160°C, 161°C, 162°C, 163°C, 164°C, 165°C, 166°C, 167°C, 168°C, 169°C, 170°C, 171°C, 172°C, 173°C, 174°C, 175°C, 176°C, 177°C, 178°C, 179°C, 180°C or any two of the above values); and heating for 6 to 24 hours (e.g., 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, 24 hours or any number between any two of the above numerical ranges) until the reaction is completed when no solids are produced, stopping the phosgene introduction and lowering the temperature to room temperature; and

[0133] (vii). Collecting the pentamethylene diisocyanate prepared in step (vi).

[0134] In certain embodiments, the lysine decarboxylase in step (i) is purified lysine decarboxylase or is derived from bacteria expressing lysine decarboxylase.

[0135] In certain embodiments, step (v) is replaced by passing phosgene into the first mixed solution obtained in step (iv), adjusting the heating temperature to 70-120°C (e.g., 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, or any value between any two of the above values), and then adding the pentamethylenediamine derivative by a stream addition method to form a second solution. In certain embodiments, step (v) is replaced by passing phosgene into the first mixed solution obtained in step (iv), adjusting the heating temperature to 80-100°C, and then adding the pentamethylenediamine derivative by a stream addition method to form a second solution. In certain embodiments, the duration of the stream addition is 1-3 hours (e.g., 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, or any value between any two of the above values). In certain embodiments, the duration of the stream addition is 2 hours.

[0136] In certain embodiments, the present application provides a method for preparing pentamethylene diisocyanate, wherein the method comprises:

[0137] (i) Carbon dioxide is introduced into the lysine solution to form lysine carbonate (bi) salt, and then the lysine carbonate (bi) salt reacts with lysine decarboxylase to generate a mixture comprising a PDA·CO2 covalent compound;

[0138] (ii) The mixture comprising the PDA·CO2 covalent compound obtained in step (i) is heated to the sublimation temperature of the PDA·CO2 covalent compound to obtain a gaseous PDA·CO2 covalent compound;

[0139] (iii) The gaseous PDA·CO2 covalent compound obtained in step (ii) is subjected to desublimation treatment to obtain a solid form of PDA·CO2 covalent compound;

[0140] (iv) The solid form of the PDA·CO2 covalent compound obtained in step (iii) is mixed with a solvent to form a first mixed solution;

[0141] (v) Phosgene is introduced into the first mixed solution obtained in step (iv), and the heating temperature is adjusted to 100-150°C (e.g., 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C or any value between any two of the above values), and heated for 1-6 hours (e.g., 1, 2, 3, 4, 5, 6 hours or any value within the range between any two of the above values) until the PDA·CO2 covalent compound reacts completely and no longer produces hydrogen chloride gas, thereby forming a second solution;

[0142] (vi) adjusting the temperature of the second solution obtained in step (v) to above 150°C (e.g., 160-180°C, for example, 160°C, 161°C, 162°C, 163°C, 164°C, 165°C, 166°C, 167°C, 168°C, 169°C, 170°C, 171°C, 172°C, 173°C, 174°C, 175°C, 176°C, 177°C, 178°C, 179°C, 180°C or any two of the above values); and heating for 6 to 24 hours (e.g., 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, 24 hours or any number between any two of the above numerical ranges) until the reaction is completed when no solids are produced, stopping the phosgene introduction and lowering the temperature to room temperature; and

[0143] (vii). Collecting the pentamethylene diisocyanate prepared in step (vi).

[0144] In certain embodiments, the lysine decarboxylase in step (i) is purified lysine decarboxylase or is derived from bacteria expressing lysine decarboxylase.

[0145] In certain embodiments, step (v) is replaced by passing phosgene into the first mixed solution obtained in step (iv), adjusting the heating temperature to 70-120°C (for example, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C or any value between any two of the above values), and then adding the PDA·CO2 covalent compound by stream addition to form a second solution. In certain embodiments, step (v) is replaced by passing phosgene into the first mixed solution obtained in step (iv), adjusting the heating temperature to 80-100°C, and then adding the PDA·CO2 covalent compound by stream addition to form a second solution. In certain embodiments, the duration of the stream addition is 1 to 3 hours (for example, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours or any value between any two of the above values). In certain embodiments, the duration of the stream addition is 2 hours.

[0146] Step (d)

[0147] Optionally, the method for preparing pentamethylene diisocyanate provided in the present application further comprises step (d): collecting pentamethylene diisocyanate prepared in step (c).

[0148] The pentamethylene diisocyanate prepared in step (c) can be collected using conventional methods known in the art. For example, the pentamethylene diisocyanate can be collected by removing the solvent through negative pressure concentration and then using negative pressure vacuum distillation.

[0149] The method for preparing pentamethylene diisocyanate provided in this application has at least the following advantages:

[0150] (1) Compared with the conventional method of first converting a pentamethylenediamine salt into pentamethylenediamine and then reacting it with phosgene to prepare pentamethylenediisocyanate, the pentamethylenediamine derivative provided by the present invention (particularly a PDA·CO2 covalent compound) can be purified after simple sublimation and desublimation treatment and then directly reacted with phosgene in a liquid phase to prepare pentamethylenediisocyanate. The entire reaction process is simple to operate and can be produced continuously.

[0151] (2) In the method for preparing pentamethylene diisocyanate provided by the present invention, the reaction process is relatively gentle, the selectivity of the prepared target product is high, and the amount of by-products produced is small;

[0152] (3) In the method for preparing pentamethylene diisocyanate provided by the present invention, the amount of solvent used is reduced, the amount of phosgene used is saved, the generation of by-products is reduced, and the yield is improved by adding pentamethylenediamine derivatives (especially PDA·CO2 covalent compounds).

[0153] In another aspect, the present application also provides an apparatus for preparing pentamethylene diisocyanate, which is used to perform the method for preparing pentamethylene diisocyanate according to the present application.

[0154] The above is a summary of this application, which may contain simplifications, generalizations, and omissions of details. Therefore, those skilled in the art should recognize that this section is illustrative only and is not intended to limit the scope of this application in any way. This summary is neither intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0155] Example

[0156] In order to more fully understand the present invention, the following examples are shown. It should be understood that these examples are for illustrative purposes only and are not to be construed as limiting in any way.

[0157] Example 1: Preparation of crude pentamethylenediamine derivatives

[0158] The Escherichia coli engineered bacteria containing lysine decarboxylase were cultured in a 15 L fermenter for 30 hours, and then centrifuged in a high-speed centrifuge at a speed of 8000 rpm for 10 minutes to obtain wet Escherichia coli engineered bacteria, which were collected for later use.

[0159] A 600g / L lysine carbonate (bicarbonate) solution was prepared by adding 420g of 99% lysine to 680ml of water, stirring to dissolve the solution, and then introducing carbon dioxide until the pH reached 7.1-7.6. The carbon dioxide supply was then stopped. 9g of wet cells of the engineered Escherichia coli bacteria containing lysine decarboxylase prepared above and 0.05g of pyridoxal phosphate were then added. The reaction was initiated at 37°C. The pH was not controlled during the reaction, and the reaction was terminated after 10 hours of reaction. The lysine content, as measured by HPLC, was <0.5% (w / v).

[0160] The reaction solution was passed through a 0.2 μm ceramic membrane to remove large particle impurities, such as bacteria and bacterial fragments, and through a 10 KD ultrafiltration membrane to remove small molecular impurities, such as nucleic acids and nucleic acid fragments, amino acids, proteins, and other impurities in the fermentation broth. The solution was then concentrated under reduced pressure to 680 g and directly dried in a vacuum oven at 50-70° C. to obtain 467.3 g of a white solid with a pentamethylenediamine carbonate content of 98.1% and a yield of 94.7%.

[0161] Example 2: Purification and structure confirmation of compounds

[0162] purification

[0163] First, the inventors purified the pentamethylenediamine derivative prepared in Example 1. Specifically, the white solid prepared in Example 1 was heated and stirred at 70-140°C in a sealed container, causing gradual sublimation. The sublimated gaseous material was transported through a heated pipeline, and the obtained gaseous material was desublimated in a pipeline at a temperature below 80°C to obtain a pure white, dense solid.

[0164] During the aforementioned experiments, the inventors discovered that, unlike other amines that absorb CO₂ and then decompose upon heating, releasing the absorbed CO₂, the pentamethylenediamine derivative prepared in Example 1 of the present application forms a stable compound that does not release CO₂ upon heating but instead sublimes in a 1:1 ratio. The elemental analysis of the sublimated material is consistent with that of the pre-sublimated material, but the density (compactness) and hardness of the sublimated material increase.

[0165] Structure confirmation

[0166] (1) Elemental analysis

[0167] The elemental analysis of the material before and after sublimation was carried out to study its composition. It is known that its elemental composition is roughly C a H b N2O c , the elemental composition analysis is as follows:

[0168] The molecular weight of the sample can be inferred from the fixed composition of two nitrogen atoms in the sample and the nitrogen content obtained from elemental analysis. The number of carbon / hydrogen atoms can be inferred from the sample molecular weight combined with the carbon / hydrogen content. The oxygen content has not been determined, but the number of oxygen atoms can be inferred from the ratio of the content of each element.

[0169] As shown above, the elemental composition of the sample is C6H 14 N2O2, expressed as H2N(CH2)5NH2·CO2 or PDA·CO2.

[0170] (2) NMR analysis

[0171] The same PDA·CO2 sample was analyzed by NMR using different deuterated solvents, and different NMR characterization information was found. The NMR analysis spectrum after dissolving in deuterated methanol is shown in Figure 1. The pentamethylenediamine derivative prepared in Example 1 was subjected to one-dimensional NMR analysis using deuterated water solvent ( 1 H-NMR analysis, 13 C-NMR analysis) and 2D NMR analysis ( 1 H- 1 H COSY and 1 H- 13 C COSY), and the obtained NMR analysis spectra are shown in Figures 2, 3, 4 and 5 respectively.

[0172] After preliminary analysis, the inventors believe that the pentamethylenediamine derivative prepared in Example 1 is not carbonate (CO3 2- ) or bicarbonate (HCO3 - ) ionic bond form, but a covalent compound that tends to be PDA and CO2. The pentamethylenediamine derivative solution obtained in Example 1, after undergoing the concentration and drying process, is not a traditional PDA carbonate containing ionic bonds, but a PDA·CO2 covalent compound in the form of a mixture.

[0173] According to existing reports (Ciftja, AF; Hartono, A.; Svendsen, F. “Carbamate Formation in Aqueous-Diamine-CO2 Systems” Energy Procedia, 2013, 37, 1605) and the spectra of Figures 2, 3, 4 and 5, the pentamethylenediamine derivative prepared in Example 1 is a mixture mainly including the following three structures:

[0174] The molar ratio of the three is 2:1:1.

[0175] Example 3: Preparation of pentamethylene diisocyanate

[0176] Weigh 20 g of the purified PDA·CO2 covalent compound from Example 2 and 200 g of o-dichlorobenzene into a multi-necked flask. Connect the tail gas absorber and start stirring while introducing phosgene. Adjust the heating temperature to 130°C and heat for 2 hours. The first stage reaction is complete when the PDA·CO2 particles in the solution disappear and hydrochloric acid gas no longer forms.

[0177] During the second reaction stage, the internal temperature was maintained at 160-180°C for 8 hours. The reaction was terminated when the solution became clear and free of particles. Phosgene was then discontinued, and the temperature was lowered while nitrogen was introduced. When the temperature returned to room temperature, samples were collected for analysis. The resulting pentamethylene diisocyanate had a purity of 99.0% and a yield of 90%.

[0178] Example 4: Preparation of pentamethylene diisocyanate (feed addition method)

[0179] Example 4.1

[0180] 400g of o-dichlorobenzene and 60g of the purified PDA·CO2 covalent compound in Example 2 were added to a reaction flask and stirred. Phosgene was introduced (at a flow rate of 1.6L / min) and heating was started. The temperature was raised to 80-100°C. 60g of the purified PDA·CO2 covalent compound in Example 2 was then added to the reaction solution through a screw feeder. The feeding duration was 2h. The temperature was then raised to above 150°C and the reaction was kept warm for 8-10h. At this point, the reaction solution was essentially clear, the temperature was lowered, the introduction of phosgene was stopped, and samples were taken for analysis. The analysis showed that the reaction was complete, and the reaction solution was transferred to a distillation tower for rectification. 119.3g of pentamethylene diisocyanate was obtained with a purity of 99.8% and a yield of 94.2%.

[0181] Example 4.2

[0182] 560g of o-dichlorobenzene and 100g of the purified PDA·CO2 covalent compound in Example 2 were added to a reaction flask and stirred. Phosgene was introduced (at a flow rate of 1.6L / min) and heating was started. The temperature was raised to 80-100°C. 100g of the purified PDA·CO2 covalent compound in Example 2 was then added to the reaction solution through a screw feeder. The feeding duration was 2h. The temperature was then raised to above 150°C and the reaction was kept warm for 8-10h. At this point, the reaction solution was essentially clear, the temperature was lowered, the introduction of phosgene was stopped, and samples were taken for analysis. The analysis showed that the reaction was complete, and the reaction solution was transferred to a distillation tower for rectification. 201.4g of pentamethylene diisocyanate was obtained with a purity of 99.7% and a yield of 95.4%.

[0183] Comparative Example

[0184] Referring to the method of Chinese Patent CN107602419B, 61.2 g of pentamethylenediamine and 612 g of o-dichlorobenzene were directly mixed and stirred at room temperature while passing dry CO₂ gas (0.5 L / min) until the pH of the system was neutral. During the process, a large amount of white, serous salt was observed floating on the liquid surface (see Figure 6). After vigorous mechanical stirring, it became a viscous paste (see Figure 7), and the system was opaque. Phosgene was introduced and the temperature reaction was forced to continue. Distillation yielded 78.5 g of pentamethylene diisocyanate with a purity of 97.1% and a yield of 84.1%.

[0185] It can be seen from this that according to the method of the comparative test, the salt formation process in the system is first not easy to form a transparent system, and there will be a phenomenon of salt wrapping the solvent, which makes it relatively difficult to increase the concentration of the raw substrate (for example, difficult to reach 10%), and the reaction efficiency of the phosgene reaction is low. Obviously, the method of the present invention using PDA·CO2 covalent compound as the starting material for phosgenation reaction to prepare isocyanate is different from the method of preparing isocyanate using PDA as the starting material, and is also different from the method of directly salifying pure PDA and then using PDA salt as the starting material. Using the method of the present invention, not only can the reaction steps be saved, but the reaction substrate concentration is higher, and the reaction can proceed smoothly. More particularly, using the flow addition method provided by the present invention, by controlling the flow rate of the flow addition PDA·CO2 covalent compound, the reaction can be carried out well, which is equivalent to further increasing the concentration of the substrate (for example, increasing the mass ratio of the PDA·CO2 covalent compound to the solvent to 1:4), reducing the amount of organic solvent used, increasing production efficiency, and saving phosgene consumption.

Claims

1. A pentamethylenediamine derivative, whose chemical formula is H2N(CH2)5NH2CO2, wherein: The N atom and the C atom are connected by covalent bonds.

2. The pentamethylenediamine derivative according to claim 1, which has an amide ester structure.

3. The pentamethylenediamine derivative according to claim 2, which has the chemical structure shown below: and / or 4. The pentamethylenediamine derivative according to any one of the preceding claims, which is present in the form of a mixture.

5. The pentamethylenediamine derivative according to claim 4, comprising the following structure:

6. The pentamethylenediamine derivative according to claim 5, wherein The total molar amount and The molar amounts are essentially the same.

7. The pentamethylenediamine derivative according to any one of the preceding claims, which does not release carbon dioxide at a temperature of 70 to 140°C.

8. The pentamethylenediamine derivative according to any one of the preceding claims, which has a sublimation temperature of 70 to 140°C.

9. The pentamethylenediamine derivative according to any one of the preceding claims, which has different chemical bonding modes in deuterated water solvent and other deuterated solvents.

10. The pentamethylenediamine derivative according to any one of the preceding claims, wherein the NMR analysis spectrum of the pentamethylenediamine derivative after being dissolved in the deuterated solvent CD3OD is shown in FIG1 .

11. The pentamethylenediamine derivative according to any one of the preceding claims, which is dissolved in a deuterated water solvent (D2O) 1 H-NMR analysis and 13 The C-NMR analysis spectra are shown in Figures 2 and 3 respectively.

12. The pentamethylenediamine derivative according to any one of the preceding claims, 1 H- 1 H COSY spectrum and 1 H- 13 The C COSY spectra are shown in Figures 4 and 5, respectively.

13. The pentamethylenediamine derivative according to any one of the preceding claims, which does not contain carbonate ions (CO3 2- ) or bicarbonate ion (HCO3 - ).

14. A method for purifying a pentamethylenediamine derivative, wherein the method comprises heating a mixture comprising the pentamethylenediamine derivative according to any one of the preceding claims to a sublimation temperature of the pentamethylenediamine derivative to obtain a gaseous pentamethylenediamine derivative.

15. The method according to claim 14, wherein the sublimation temperature is 70 to 140°C.

16. The method according to claim 14 or 15, wherein the method does not include a step of alkalizing the mixture comprising the pentamethylenediamine derivative using an alkaline substance.

17. The method according to claim 16, wherein the alkaline substance is selected from the group consisting of sodium hydroxide, potassium hydroxide, ammonia water, calcium hydroxide, magnesium hydroxide, calcium oxide, magnesium oxide, and any combination thereof.

18. The method according to any one of claims 14 to 17, wherein the method further comprises desublimating the obtained gaseous pentamethylenediamine derivative.

19. The method according to claim 18, wherein the desublimation treatment is performed at 30 to 50°C.

20. The method according to any one of claims 14 to 19, wherein the mixture containing pentamethylenediamine derivatives is prepared by the following method: carbon dioxide is introduced into lysine to form lysine carbonate (bi) salt, and then the lysine carbonate (bi) salt is reacted with lysine decarboxylase to generate pentamethylenediamine derivatives.

21. A method for preparing pentamethylene diisocyanate, wherein the method comprises: (a) mixing the pentamethylenediamine derivative according to any one of claims 1 to 13 or the pentamethylenediamine derivative purified by the method according to any one of claims 14 to 20 with a solvent to form a first mixed solution; (b) introducing phosgene into the first mixed solution obtained in step (a), adjusting the heating temperature to 100-150° C., and heating for 1-6 hours until the pentamethylenediamine derivative reacts completely and no longer generates hydrogen chloride gas, thereby forming a second solution; (c) adjusting the temperature of the second solution obtained in step (b) to 160-180° C. and heating the solution for 6-24 hours until the reaction is complete when no solids are present, stopping the introduction of phosgene, and lowering the temperature to room temperature.

22. The method according to claim 21, wherein step (b) is replaced by introducing phosgene into the first mixed solution obtained in step (a), adjusting the heating temperature to 70-120°C, and then adding the pentamethylenediamine derivative by a flow addition method, wherein the flow addition lasts for 1 to 3 hours, to form a second solution.

23. The method according to claim 22, wherein the feeding in step (b) is carried out by a screw feeding device.

24. The method according to claim 22 or 23, wherein the feeding is a uniform feeding.

25. The method according to any one of claims 21 to 24, wherein the solvent in step (a) is selected from the group consisting of dichloromethane, chlorobenzene, o-dichlorobenzene, benzene, toluene, xylene, hexane, tetrahydrofuran, chloronaphthalene, and any combination thereof.

26. The method according to any one of claims 21 to 25, wherein in step (a), the mass ratio of the pentamethylenediamine derivative to the solvent is 1:1 to 1:

12.

27. The method according to any one of claims 21 to 26, wherein the flow rate of phosgene introduced in step (b) is 0.5 to 5 L / min; or the molar ratio of phosgene introduced in step (b) to the amino group of the pentamethylenediamine derivative described in step (a) is 1.1:1 to 50:

1.

28. The method according to any one of claims 21 to 27, wherein the second solution obtained in step (b) contains an aminoacyl chloride.

29. The method according to any one of claims 21 to 28, wherein an inert gas is introduced simultaneously during the temperature reduction in step (c).

30. The method of claim 29, wherein the inert gas is selected from the group consisting of nitrogen, carbon dioxide, carbon monoxide, helium, argon, and any combination thereof.

31. The method according to any one of claims 21 to 30, wherein the room temperature in step (c) is in the range of -10°C to 40°C.

32. The method according to any one of claims 21 to 31, wherein the method further comprises step (d): The pentamethylene diisocyanate prepared in step (c) is collected.

33. A method for preparing pentamethylene diisocyanate, wherein the method comprises: (i) introducing carbon dioxide into a lysine solution to form lysine carbonate (bicarbonate), and then reacting the lysine carbonate (bicarbonate) with lysine decarboxylase to generate a mixture comprising a pentamethylenediamine derivative; (ii) heating the mixture containing the pentamethylenediamine derivative obtained in step (i) to the sublimation temperature of the pentamethylenediamine derivative to obtain a gaseous pentamethylenediamine derivative; (iii) The gaseous pentamethylenediamine derivative obtained in step (ii) is subjected to desublimation treatment to obtain a solid pentamethylenediamine derivative; (iv) mixing the solid form of the pentamethylenediamine derivative obtained in step (iii) with a solvent to form a first mixed solution; (v) phosgene is introduced into the first mixed solution obtained in step (iv), the heating temperature is adjusted to 100 to 150 ° C, and the mixture is heated for 1 to 6 hours until the pentamethylenediamine derivative reacts completely and no longer produces hydrogen chloride gas to form a second solution; (vi) adjusting the temperature of the second solution obtained in step (v) to above 150°C (eg, 160 to 180°C), and heating for 6 to 24 hours until the reaction is complete without solid matter, stopping the phosgene introduction, and lowering the temperature to room temperature; and (vii). Collecting the pentamethylene diisocyanate prepared in step (vi).

34. The method according to claim 33, wherein step (v) is replaced by introducing phosgene into the first mixed solution obtained in step (iv), adjusting the heating temperature to 70-120°C, and then adding the pentamethylenediamine derivative by means of a flow addition method, wherein the flow addition lasts for 1 to 3 hours, to form a second solution.

35. The method according to claim 33 or 34, wherein the lysine decarboxylase described in step (i) is purified lysine decarboxylase or is from a bacterium expressing lysine decarboxylase.

36. An apparatus for preparing pentamethylene diisocyanate, the apparatus being used to carry out the method according to any one of claims 14 to 35.

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