A catalyst for synthesizing polyethylene polyamines by ethylene dichloride method and a method for synthesizing polyethylene polyamines by using the catalyst

Abstract

The present invention relates to the technical field of polyethylene polyamine synthesis, and in particular to a catalyst for synthesizing polyethylene polyamines by an ethylene dichloride method and a method for synthesizing polyethylene polyamines by using the catalyst. Conventional EDC method synthesizes polyethylene polyamines, and the yield of polyethylene polyamines is low, and it is difficult to reach more than 75%. In view of the above problems, the present invention provides a catalyst for synthesizing polyethylene polyamines by an ethylene dichloride method and a method for synthesizing polyethylene polyamines by using the catalyst, which includes a basic metal active component, 1,3-diazolyl, an additional metal element, and an oxygen element and a silicon dioxide skeleton that match the metal element in the catalyst. The present invention significantly improves the yield of polyethylene polyamines obtained by the EDC method and the conversion rate of ethylene dichloride by adjusting the metal element composition of the catalyst and additionally adding 1,3-diazolyl as a new component of the catalyst.

Description

Technical Field

[0001] The invention relates to the technical field of polyethylene polyamine synthesis, and in particular to a catalyst for synthesizing polyethylene polyamine using an ethylene dichloride method and a method for synthesizing polyethylene polyamine using the catalyst. Background Art

[0002] Ethyleneamine, also known as ethyleneamine, has a general molecular formula of H2N(C2H4NH)nH. It is an important fine chemical intermediate and is widely used in organic synthesis, dyes, medicines, chemical additives, pesticides, rubber and plastic additives, organic solvents and epoxy resin curing agents.

[0003] The main methods for synthesizing ethyleneamine include the ethylene dichloride method (EDC), the ethanolamine method (MEA), the ethylene amination method, the formaldehyde-hydrocyanic acid method, the diethylene glycol amination method, the chloroacetyl chloride amination method, and the aminoacetonitrile hydrogenation method. The methods for industrial production of ethyleneamine are mainly the EDC method and the MEA method. Other methods have not yet been industrialized due to reasons such as raw material sources and costs. The EDC method is obtained by reacting ethylene dichloride with ammonia.

[0004] In the prior art, when the EDC method is used to synthesize polyethylene polyamines, the conversion rate of ethylene dichloride is low, the yield of polyethylene polyamines is poor, and the total yield is usually around 50%. After adding a catalyst, the yield can be increased to 60%, but it is difficult to reach more than 75%. Summary of the invention

[0005] The problem in the prior art is that the conventional EDC method for synthesizing polyethylene polyamines has a low yield of polyethylene polyamines, which is difficult to reach more than 75%. In view of the above problems, the present invention provides a catalyst for synthesizing polyethylene polyamines by ethylene dichloride method and a method for synthesizing polyethylene polyamines using the catalyst, which comprises a basic metal active component, 1,3-diazolyl, an additional metal element, and an oxygen element and a silicon dioxide skeleton that match the metal element in the catalyst.

[0006] The basic metal active components include Fe, Cu and at least one La-based metal, Fe accounts for 35-45% of the total weight of the metal active components, Cu accounts for 30-40% of the total weight of the metal active components, and La-based metals account for 5-10% of the total weight of the metal active components. The content of the basic metal active components accounts for 30-35% of the total mass of the catalyst.

[0007] The additional metal elements include one or two of Mo, W, Ni, Sn, Bi, Mn, Ti, Zr, and Co.

[0008] The content of the additional metal element accounts for 10-15% of the total mass of the catalyst.

[0009] The 1,3-diazolyl accounts for 30-45% of the total mass of the catalyst.

[0010] Preferably, the lanthanide metal includes at least one of La, Ce, Nd and Sm.

[0011] Preferably, the lanthanide metal is Nd.

[0012] Preferably, the additional metal elements are Co and Mo, and the atomic ratio of Co to Mo is 2:1.

[0013] Preferably, Fe accounts for 40-45% of the total weight of the metal active components, Cu accounts for 30-35% of the total weight of the metal active components, and La-based metals account for 8-10% of the total weight of the metal active components.

[0014] The additional metal elements include one or two of Mo, W, Ni, Sn, Bi, Mn, Ti, Zr, and Co.

[0015] The content of the additional metal element accounts for 10-12% of the total mass of the catalyst.

[0016] The 1,3-diazolyl accounts for 30-35% of the total mass of the catalyst.

[0017] Preferably, the catalyst for synthesizing polyethylene polyamines by the ethylene dichloride method comprises the following steps:

[0018] (1) Weighing the soluble salt of the metal element oxide in the catalyst, respectively preparing a metal salt aqueous solution with a molar content of 0.008-0.015 M and placing it in a measuring bottle, and preparing an alkaline precipitant solution and placing it in a measuring bottle;

[0019] (2) adding pure water to a reaction tank, heating to 95±2° C. under stirring, adding a plurality of metal aqueous solutions in parallel, stirring at 250-300 rpm, slowly adding an alkali precipitant according to the isoelectric point at which the soluble metal salt in the raw material is completely precipitated, controlling the flow rate of the alkali precipitant, and using a stepwise pH swing method to achieve metal precipitation, the pH swing is repeated 5-8 times, the acid side pH=3.8-4.0, the alkaline side=10.1-10.5, the reaction end point pH=3.8-4.0, the overall time is 170-180 min, and at the same time, the solid content of the colloidal system is controlled to 0.5-2.0% by adding water. After the reaction is completed, the entire system is crystallized at 120-150° C. for 36 h, and then the pH is adjusted to 7.8-8.0, and then crystallized at 120-150° C. for 36-40 h, filtered to obtain a filter cake, and the filter cake is washed with pure water several times until the conductivity of the washing water is ≤10 μs / cm;

[0020] (3) mixing the qualified filter cake obtained after washing in step (2) with the carrier by adding water to adjust to a slurry, controlling the solid content at 1.0-5.0%, 880-900 rpm, slurrying for 55-60 min, and adjusting the pH to 4.8-6.0;

[0021] (4) adding an aqueous solution of a binder to the mixed slurry to ensure that the mass concentration of methyl cellulose in the system is 0.05-0.06%, sealing the dispersion tank, connecting compressed air, controlling the flow rate to 60-100 mL / min, and inputting the slurry into a fluidized bed for dehydration and oxidation in a boiling state of the fluidized bed at 600-650° C. to obtain a powdered catalyst with a particle size of 700-800 nm;

[0022] (5) The powdered catalyst is uniformly dispersed in the aqueous solution, 1,3-diazolyl is added, the mixture is stirred and mixed uniformly, and vacuum dried at 70-80° C. to obtain the target catalyst.

[0023] Preferably, the binder is selected from methyl cellulose, hydroxy cellulose or polyvinyl alcohol.

[0024] Preferably, the soluble salts include nitrates, hydrochlorides, acetates, wherein Mo and W are both oxygen-containing salts.

[0025] Preferably, the alkaline precipitant is sodium hydroxide, sodium carbonate, ammonium hydroxide or an organic amine, wherein the organic amine is triethylamine or n-butylamine.

[0026] Preferably, the carrier is silicon dioxide, which is added in the form of silica sol or ethyl silicate.

[0027] Preferably, the polyethylene polyamine is prepared according to the catalyst, and the preparation method thereof comprises the following steps:

[0028] (1) Open the feeding valve and pressure reducing valve to exhaust the air in the reactor, add 8 kg of catalyst and 1750 kg of water into the reactor in sequence, mix and stir evenly,

[0029] (2) Close the feeding valve and the pressure reducing valve, add liquid ammonia into the reactor to form a dilute ammonia water with a mass concentration of 30% in the reactor, then stir and heat to 110° C., then add 300 kg of ethylene dichloride into the reactor, the feeding time is 30 min, the ammonia-alkane ratio is 24.4, and the reaction is stirred at a constant temperature until the temperature in the reactor reaches 140° C., then turn on the cooling water to cool the reaction system, control the reaction temperature between 135-145° C. and keep warm for 30 min, and the reaction pressure is 2.45 mPa;

[0030] (3) Then, the temperature of the reaction system is lowered to below 100° C., the pressure reducing valve is slowly opened, the pressure in the reactor is reduced to atmospheric pressure, the pressure reducing valve is closed, the feed valve is opened, and the reaction materials are placed in a neutralization reactor for alkali neutralization reaction. The reaction temperature is 70° C. and the reaction time is 40 min. After the reaction is completed, vacuum distillation is performed to obtain polyethylene polyamine.

[0031] Preferably, the alkaline solution used in the alkali neutralization reaction is a solution obtained by adding 255 kg of caustic soda into 180 kg of water and stirring to completely dissolve the solution.

[0032] The present invention has the following beneficial effects:

[0033] (1) The present invention significantly improves the yield of polyethylene polyamines obtained by the EDC method and the conversion rate of ethylene dichloride by adjusting the metal element composition of the catalyst and adding 1,3-diazolyl as a new component of the catalyst;

[0034] (2) The catalyst obtained by the present invention has a higher selectivity for triethylenetetramine in polyethylene polyamines, and the selectivity can reach more than 40%. The total yield of polyethylene polyamines reaches more than 75%, achieving a good technical effect. DETAILED DESCRIPTION

[0035] The present invention is described in detail below with reference to the examples. However, it should be understood that the following examples are only illustrative of the embodiments of the present invention, and are not intended to limit the scope of the present invention.

[0036] The present invention adopts the sol-gel method, firstly, the soluble salt solution of the metal elements in the catalyst reacts with the alkaline precipitant to form a sol, the diameter of the sol particles is about 70-90nm, then skeleton silicon dioxide and a binder are added, and the sol particles are dehydrated and oxidized in a fluidized bed boiling state at 600-650℃ to obtain a powdered catalyst with a particle size of 700-800nm ​​and a total specific surface area of ​​380-430m 2 / g, pore volume 0.68-0.73mL / g, the powdered catalyst is evenly dispersed in the aqueous solution, 1,3-diazolyl is added, stirred and mixed evenly, and vacuum dried at 70-80°C to obtain the target catalyst.

[0037] Example 1

[0038] A catalyst for synthesizing polyethylene polyamines by the ethylene dichloride method, the preparation method is as follows:

[0039] The catalyst consists of basic metal active components, 1,3-diazolyl, additional metal elements, oxygen elements and a silicon dioxide skeleton that match the metal elements in the catalyst. The basic metal active components are Fe, Cu and Nd, Fe accounts for 40% of the total weight of the metal active components, Cu accounts for 35% of the total weight of the metal active components, Nd accounts for 8% of the total weight of the metal active components, the content of the basic metal active components accounts for 32% of the total mass of the catalyst, the additional metal elements are Co and Mo, the atomic ratio of Co to Mo is 2:1, the content of the additional metal elements accounts for 12% of the total mass of the catalyst, and 1,3-diazolyl accounts for 30% of the total mass of the catalyst.

[0040] (1) According to the formula, weigh the soluble salt of the metal element oxide in the catalyst, prepare a metal salt aqueous solution with a molar content of 0.008-0.015M and place it in a measuring bottle, and prepare an alkaline precipitant solution and place it in a measuring bottle;

[0041] (2) 1000 mL of pure water was added to a reaction tank, heated to 95±2° C. under stirring, and a metal aqueous solution was added in multiple streams in parallel, and stirred at 250-300 rpm. According to the isoelectric point at which the soluble metal salt in the raw material is completely precipitated, an alkaline precipitant was slowly added, and the flow rate of the alkaline precipitant was controlled. The precipitation of the metal was achieved by a stepwise pH swing method, and the pH swing was repeated 5-8 times, the acid side pH = 3.8-4.0, the alkaline side = 10.1-10.5, the reaction end point pH = 3.8-4.0, the overall time was 170-180 min, and at the same time, the solid content of the colloidal system was controlled to 0.5-2.0% by adding water. After the reaction was completed, the whole system was crystallized at 120-150° C. for 36 h, and then the pH was adjusted to 7.8-8.0, and then crystallized at 120-150° C. for 36-40 h, filtered to obtain a filter cake, and the filter cake was washed with pure water several times until the conductivity of the washing water was ≤10 μs / cm;

[0042] (3) mixing the qualified filter cake obtained after washing in step (2) with the carrier by adding water to adjust to a slurry, controlling the solid content at 1.0-5.0%, 880-900 rpm, slurrying for 55-60 min, and adjusting the pH to 4.8-6.0;

[0043] (4) adding an aqueous solution of a binder to the mixed slurry to ensure that the mass concentration of methyl cellulose in the system is 0.05-0.06%, sealing the dispersion tank, connecting compressed air, controlling the flow rate to 60-100 mL / min, and inputting the slurry into a fluidized bed for dehydration and oxidation in a boiling state of the fluidized bed at 600-650° C. to obtain a powdered catalyst with a particle size of 700-800 nm;

[0044] (5) The powdered catalyst is uniformly dispersed in the aqueous solution, 1,3-diazolyl is added, the mixture is stirred and mixed uniformly, and vacuum dried at 70-80° C. to obtain the target catalyst.

[0045] The adhesive is polyvinyl alcohol.

[0046] The soluble salts are respectively nitrates of Fe, Cu, Nd, Co and sodium molybdate.

[0047] The alkaline precipitant is sodium hydroxide.

[0048] The carrier is silicon dioxide, which is added in the form of silica sol. Silica sol is a solution formed by dissolving silica gel in water, with a specific gravity of 1.15 g / cm 3 The CAS number of silica gel is 63231-67-4.

[0049] Example 2

[0050] A catalyst for synthesizing polyethylene polyamines by the ethylene dichloride method, the preparation method is as follows:

[0051] The catalyst consists of basic metal active components, 1,3-diazolyl, additional metal elements, oxygen elements and a silicon dioxide skeleton that match the metal elements in the catalyst. The basic metal active components are Fe, Cu and Nd, Fe accounts for 40% of the total weight of the metal active components, Cu accounts for 35% of the total weight of the metal active components, Nd accounts for 8% of the total weight of the metal active components, the content of the basic metal active components accounts for 32% of the total mass of the catalyst, the additional metal elements are Co and Mo, the atomic ratio of Co to Mo is 2:1, the content of the additional metal elements accounts for 12% of the total mass of the catalyst, and 1,3-diazolyl accounts for 30% of the total mass of the catalyst.

[0052] (1) According to the formula, weigh the soluble salt of the metal element oxide in the catalyst, prepare a metal salt aqueous solution with a molar content of 0.008-0.015M and place it in a measuring bottle, and prepare an alkaline precipitant solution and place it in a measuring bottle;

[0053] (2) 1000 mL of pure water was added to a reaction tank, heated to 95±2° C. under stirring, and a metal aqueous solution was added in multiple streams in parallel, and stirred at 250-300 rpm. According to the isoelectric point at which the soluble metal salt in the raw material is completely precipitated, an alkaline precipitant was slowly added, and the flow rate of the alkaline precipitant was controlled. The precipitation of the metal was achieved by a stepwise pH swing method, and the pH swing was repeated 5-8 times, the acid side pH = 3.8-4.0, the alkaline side = 10.1-10.5, the reaction end point pH = 3.8-4.0, the overall time was 170-180 min, and at the same time, the solid content of the colloidal system was controlled to 0.5-2.0% by adding water. After the reaction was completed, the whole system was crystallized at 120-150° C. for 36 h, and then the pH was adjusted to 7.8-8.0, and then crystallized at 120-150° C. for 36-40 h, filtered to obtain a filter cake, and the filter cake was washed with pure water several times until the conductivity of the washing water was ≤10 μs / cm;

[0054] (3) mixing the qualified filter cake obtained after washing in step (2) with the carrier by adding water to adjust to a slurry, controlling the solid content at 1.0-5.0%, 880-900 rpm, slurrying for 55-60 min, and adjusting the pH to 4.8-6.0;

[0055] (4) adding an aqueous solution of a binder to the mixed slurry to ensure that the mass concentration of methyl cellulose in the system is 0.05-0.06%, sealing the dispersion tank, connecting compressed air, controlling the flow rate to 60-100 mL / min, and inputting the slurry into a fluidized bed for dehydration and oxidation in a boiling state of the fluidized bed at 600-650° C. to obtain a powdered catalyst with a particle size of 700-800 nm;

[0056] (5) The powdered catalyst is uniformly dispersed in the aqueous solution, 1,3-diazolyl is added, the mixture is stirred and mixed uniformly, and vacuum dried at 70-80° C. to obtain the target catalyst.

[0057] The binder is methyl cellulose.

[0058] The soluble salts are respectively nitrates of Fe, Cu, Nd, Co and sodium molybdate.

[0059] The alkaline precipitant is sodium carbonate.

[0060] The carrier is silicon dioxide, which is added in the form of silica sol. Silica sol is a solution formed by dissolving silica gel in water, with a specific gravity of 1.15 g / cm 3 The CAS number of silica gel is 63231-67-4.

[0061] Example 3

[0062] A catalyst for synthesizing polyethylene polyamines by the ethylene dichloride method, the preparation method is as follows:

[0063] The catalyst consists of basic metal active components, 1,3-diazolyl, additional metal elements, oxygen elements and a silicon dioxide skeleton that match the metal elements in the catalyst. The basic metal active components are Fe, Cu and Nd, Fe accounts for 40% of the total weight of the metal active components, Cu accounts for 35% of the total weight of the metal active components, Nd accounts for 8% of the total weight of the metal active components, the content of the basic metal active components accounts for 32% of the total mass of the catalyst, the additional metal elements are Co and Mo, the atomic ratio of Co to Mo is 2:1, the content of the additional metal elements accounts for 12% of the total mass of the catalyst, and 1,3-diazolyl accounts for 30% of the total mass of the catalyst.

[0064] (1) According to the formula, weigh the soluble salt of the metal element oxide in the catalyst, prepare a metal salt aqueous solution with a molar content of 0.008-0.015M and place it in a measuring bottle, and prepare an alkaline precipitant solution and place it in a measuring bottle;

[0065] (2) 1000 mL of pure water was added to a reaction tank, heated to 95±2° C. under stirring, and a metal aqueous solution was added in multiple streams in parallel, and stirred at 250-300 rpm. According to the isoelectric point at which the soluble metal salt in the raw material is completely precipitated, an alkaline precipitant was slowly added, and the flow rate of the alkaline precipitant was controlled. The precipitation of the metal was achieved by a stepwise pH swing method, and the pH swing was repeated 5-8 times, the acid side pH = 3.8-4.0, the alkaline side = 10.1-10.5, the reaction end point pH = 3.8-4.0, the overall time was 170-180 min, and at the same time, the solid content of the colloidal system was controlled to 0.5-2.0% by adding water. After the reaction was completed, the whole system was crystallized at 120-150° C. for 36 h, and then the pH was adjusted to 7.8-8.0, and then crystallized at 120-150° C. for 36-40 h, filtered to obtain a filter cake, and the filter cake was washed with pure water several times until the conductivity of the washing water was ≤10 μs / cm;

[0066] (3) mixing the qualified filter cake obtained after washing in step (2) with the carrier by adding water to adjust to a slurry, controlling the solid content at 1.0-5.0%, 880-900 rpm, slurrying for 55-60 min, and adjusting the pH to 4.8-6.0;

[0067] (4) adding an aqueous solution of a binder to the mixed slurry to ensure that the mass concentration of methyl cellulose in the system is 0.05-0.06%, sealing the dispersion tank, connecting compressed air, controlling the flow rate to 60-100 mL / min, and inputting the slurry into a fluidized bed for dehydration and oxidation in a boiling state of the fluidized bed at 600-650° C. to obtain a powdered catalyst with a particle size of 700-800 nm;

[0068] (5) The powdered catalyst is uniformly dispersed in the aqueous solution, 1,3-diazolyl is added, the mixture is stirred and mixed uniformly, and vacuum dried at 70-80° C. to obtain the target catalyst.

[0069] The binder is hydroxy cellulose.

[0070] The soluble salts are respectively nitrates of Fe, Cu, Nd, Co and sodium molybdate.

[0071] The alkaline precipitant is ammonium hydroxide.

[0072] The carrier is silicon dioxide, which is added in the form of silica sol. Silica sol is a solution formed by dissolving silica gel in water, with a specific gravity of 1.15 g / cm 3 The CAS number of silica gel is 63231-67-4.

[0073] Comparative Example 1 is the same as Example 1, except that the catalyst in Comparative Example 1 consists of basic metal active components, 1,3-diazolyl, additional metal elements, and oxygen elements and a silica skeleton that match the metal elements in the catalyst, the basic metal active components are Fe, Cu and Nd, Fe accounts for 40% of the total weight of the metal active components, Cu accounts for 35% of the total weight of the metal active components, Nd accounts for 8% of the total weight of the metal active components, the content of the basic metal active components accounts for 42% of the total mass of the catalyst, the additional metal elements are Co and Mo, the atomic ratio of Co to Mo is 2:1, the content of the additional metal elements accounts for 12% of the total mass of the catalyst, and 1,3-diazolyl accounts for 20% of the total mass of the catalyst.

[0074] Comparative Example 2 is the same as Example 1, except that the catalyst in Comparative Example 2 consists of basic metal active components, 1,3-diazolyl, additional metal elements, and oxygen elements and a silica skeleton that match the metal elements in the catalyst. The basic metal active components are Fe, Cu and Nd, Fe accounts for 40% of the total weight of the metal active components, Cu accounts for 35% of the total weight of the metal active components, Nd accounts for 8% of the total weight of the metal active components, the content of the basic metal active components accounts for 32% of the total mass of the catalyst, the additional metal elements are Ti and Mo, the atomic ratio of Ti to Mo is 1:1, the content of the additional metal elements accounts for 12% of the total mass of the catalyst, and 1,3-diazolyl accounts for 30% of the total mass of the catalyst.

[0075] Comparative Example 3 is the same as Example 1, except that the catalyst in Comparative Example 3 consists of basic metal active components, 1,3-diazolyl, additional metal elements, and oxygen elements and a silica skeleton that match the metal elements in the catalyst. The basic metal active components are Fe, Cu and Nd, Fe accounts for 40% of the total weight of the metal active components, Cu accounts for 35% of the total weight of the metal active components, Nd accounts for 8% of the total weight of the metal active components, the content of the basic metal active components accounts for 32% of the total mass of the catalyst, the additional metal elements are Co and Mo, the atomic ratio of Co to Mo is 1:2, the content of the additional metal elements accounts for 12% of the total mass of the catalyst, and 1,3-diazolyl accounts for 30% of the total mass of the catalyst.

[0076] Comparative Example 4 is the same as Example 1, except that the catalyst in Comparative Example 4 consists of basic metal active components, 1,3-diazolyl, additional metal elements, and oxygen elements and a silica skeleton that match the metal elements in the catalyst. The basic metal active components are Fe, Cu and Nd, Fe accounts for 40% of the total weight of the metal active components, Cu accounts for 35% of the total weight of the metal active components, Nd accounts for 8% of the total weight of the metal active components, the content of the basic metal active components accounts for 22% of the total mass of the catalyst, the additional metal elements are Co and Mo, the atomic ratio of Co to Mo is 1:1, the content of the additional metal elements accounts for 12% of the total mass of the catalyst, and 1,3-diazolyl accounts for 40% of the total mass of the catalyst.

[0077] Comparative Example 5 is the same as Example 1, except that the catalyst in Comparative Example 5 consists of a basic metal active component, 1,3-diazolyl, an additional metal element, and an oxygen element and a silica skeleton that match the metal elements in the catalyst. The basic metal active components are Fe and Nd, Fe accounts for 75% of the total weight of the metal active components, Nd accounts for 8% of the total weight of the metal active components, and the content of the basic metal active components accounts for 32% of the total mass of the catalyst. The additional metal elements are Co and Mo, the atomic ratio of Co to Mo is 2:1, the content of the additional metal elements accounts for 12% of the total mass of the catalyst, and 1,3-diazolyl accounts for 30% of the total mass of the catalyst.

[0078] Comparative Example 6 is the same as Example 1, except that the catalyst in Comparative Example 6 consists of basic metal active components, 1,3-diazolyl, additional metal elements, and oxygen elements and a silica skeleton that match the metal elements in the catalyst. The basic metal active components are Fe, Cu and La, Fe accounts for 40% of the total weight of the metal active components, Cu accounts for 35% of the total weight of the metal active components, La accounts for 8% of the total weight of the metal active components, the content of the basic metal active components accounts for 32% of the total mass of the catalyst, the additional metal elements are Co and Mo, the atomic ratio of Co to Mo is 2:1, the content of the additional metal elements accounts for 12% of the total mass of the catalyst, and 1,3-diazolyl accounts for 30% of the total mass of the catalyst.

[0079] The catalysts obtained in Examples 1-3 and Comparative Examples 1-6 of the present invention were used as catalysts for the EDC method to synthesize polyethylene polyamines, and the synthesis steps were as follows:

[0080] (1) Open the feeding valve and pressure reducing valve to exhaust the air in the reactor, add 8 kg of catalyst and 1750 kg of water into the reactor in sequence, mix and stir evenly,

[0081] (2) Close the feeding valve and the pressure reducing valve, add liquid ammonia into the reactor to form a dilute ammonia water with a mass concentration of 30% in the reactor, then stir and heat to 110° C., then add 300 kg of ethylene dichloride into the reactor, the feeding time is 30 min, the ammonia-alkane ratio is 24.4, and the reaction is stirred at a constant temperature until the temperature in the reactor reaches 140° C., then turn on the cooling water to cool the reaction system, control the reaction temperature between 135-145° C. and keep warm for 30 min, and the reaction pressure is 2.45 mPa;

[0082] (3) Then, the temperature of the reaction system is lowered to below 100° C., the pressure reducing valve is slowly opened, the pressure in the reactor is reduced to atmospheric pressure, the pressure reducing valve is closed, the feed valve is opened, and the reaction materials are placed in a neutralization reactor for alkali neutralization reaction. The reaction temperature is 70° C. and the reaction time is 40 min. After the reaction is completed, vacuum distillation is performed to obtain polyethylene polyamine.

[0083] The alkaline solution used in the alkali neutralization reaction is a solution obtained by adding 255 kg of caustic soda into 180 kg of water and stirring to completely dissolve.

[0084] Performance Testing

[0085] The reaction products obtained in Examples 1-3 of the present invention and Comparative Examples 1-6 were respectively subjected to relevant performance tests, and the test results are shown in Table 1.

[0086] Table 1

[0087]

[0088] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A catalyst for synthesizing polyethylene polyamines by ethylene dichloride method, characterized in that: It includes basic metal active components, 1,3-diazolyl, additional metal elements, oxygen elements matching the metal elements in the catalyst, and a silicon dioxide skeleton. The basic metal active components include Fe, Cu and at least one La-based metal, Fe accounts for 35-45% of the total weight of the metal active components, Cu accounts for 30-40% of the total weight of the metal active components, and La-based metals account for 5-10% of the total weight of the metal active components. The content of the basic metal active components accounts for 30-35% of the total mass of the catalyst. The additional metal elements include one or two of Mo, W, Ni, Sn, Bi, Mn, Ti, Zr, and Co. The content of the additional metal element accounts for 10-15% of the total mass of the catalyst. 1,3-Diazole accounts for 30-45% of the total mass of the catalyst; The La-based metal includes at least one of La, Ce, Nd, and Sm.

2. The catalyst for synthesizing polyethylene polyamines by the ethylene dichloride process according to claim 1, characterized in that: The La-based metal is Nd.

3. The catalyst for synthesizing polyethylene polyamines by the ethylene dichloride process according to claim 1, characterized in that: The additional metal elements are Co and Mo, and the atomic ratio of Co to Mo is 2:

1.

4. The catalyst for synthesizing polyethylene polyamines by the ethylene dichloride process according to claim 1, characterized in that: Fe accounts for 40-45% of the total weight of the metal active components, Cu accounts for 30-35% of the total weight of the metal active components, and La-based metals account for 8-10% of the total weight of the metal active components. The additional metal elements include one or two of Mo, W, Ni, Sn, Bi, Mn, Ti, Zr, and Co. The content of the additional metal element accounts for 10-12% of the total mass of the catalyst. 1,3-Diazole accounts for 30-35% of the total mass of the catalyst.

5. A method for preparing a catalyst for synthesizing polyethylene polyamines by ethylene dichloride method, characterized in that: The preparation method comprises the following steps: (1) Weigh the soluble salt of the metal element oxide in the catalyst, prepare a metal salt aqueous solution with a molar content of 0.008-0.015M and place it in a measuring bottle, and prepare an alkaline precipitant solution and place it in a measuring bottle; (2) Add pure water to the reaction tank, heat to 95±2°C while stirring, add the metal aqueous solution in multiple streams in parallel, stir at 250-300rpm, slowly add the alkali precipitant according to the isoelectric point of complete precipitation of the soluble metal salt in the raw material, control the flow rate of the alkali precipitant, and use the stepwise pH swing method to achieve metal precipitation. The pH swing is repeated 5-8 times, the acid side pH = 3.8-4.0, the alkaline side pH = 10.1-10.5, the reaction end point pH = 3.8-4.0, the overall time is 170-180min, and at the same time, the solid content of the colloidal system is controlled to 0.5-2.0% by adding water. After the reaction is completed, the whole system is crystallized at 120-150°C for 36h, and then the pH is adjusted to 7.8-8.0, and then crystallized at 120-150°C for 36-40h, filtered to obtain a filter cake, and the filter cake is washed with pure water for several times until the conductivity of the washing water is ≤10μs / cm; (3) The qualified filter cake obtained after washing in step (2) is mixed with the carrier by adding water to adjust to a slurry, the solid content is controlled at 1.0-5.0%, 880-900 rpm, slurrying for 55-60 minutes, and the pH is adjusted to 4.8-6.0; (4) Adding an aqueous solution of a binder to the mixed slurry to ensure that the mass concentration of methyl cellulose in the system is 0.05-0.06%, sealing the dispersion tank, connecting compressed air, controlling the flow rate to 60-100 mL / min, and inputting the slurry into a fluidized bed for dehydration and oxidation in a boiling state of the fluidized bed at 600-650° C. to obtain a powdered catalyst with a particle size of 700-800 nm; (5) Dispersing the powdered catalyst evenly in the aqueous solution, adding 1,3-diazolyl, stirring and mixing evenly, and vacuum drying at 70-80° C. to obtain the target catalyst; The binder is methyl cellulose.

6. The preparation method according to claim 5, characterized in that: The soluble salts include nitrates, hydrochlorides, and acetates, wherein Mo and W are both oxygen-containing salts.

7. The preparation method according to claim 5, characterized in that: The carrier is silicon dioxide, which is added in the form of silica sol or ethyl silicate.

8. The catalyst according to any one of claims 1 to 4 or the preparation method according to any one of claims 5 to 7, characterized in that: The preparation method comprises the following steps: (1) Open the feeding valve and pressure reducing valve to exhaust the air in the reactor. Add 8 kg of catalyst and 1750 kg of water into the reactor in sequence and mix and stir evenly. (2) Close the feeding valve and the pressure reducing valve, add liquid ammonia into the reactor to form a dilute ammonia water with a mass concentration of 30% in the reactor, then stir and heat it to 110°C, then add 300kg of ethylene dichloride into the reactor, the feeding time is 30min, the ammonia-alkane ratio is 24.4, and the reaction is stirred at a constant temperature until the temperature in the reactor reaches 140°C, then turn on the cooling water to cool the reaction system, control the reaction temperature between 135-145°C and keep it warm for 30min, and the reaction pressure is 2.45mPa; (3) Then, the temperature of the reaction system is lowered to below 100°C, the pressure reducing valve is slowly opened, the pressure in the reactor is reduced to atmospheric pressure, the pressure reducing valve is closed, the feed valve is opened, and the reaction materials are placed in a neutralization reactor for alkaline neutralization reaction. The reaction temperature is 70°C and the reaction time is 40 min. After the reaction is completed, polyethylene polyamine is obtained by vacuum distillation.

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