Preparation method of morpholine

Abstract

The invention discloses a preparation method of morpholine, which comprises the following steps: carrying out contact reaction on a raw material containing diethylene glycol and liquid ammonia and a catalyst to obtain morpholine, the catalyst comprises a carrier and an active component loaded on the carrier; the carrier is a pure silicon molecular sieve; the active components comprise Cu, Ni and Co. The catalyst provided by the invention is applied to a reaction for preparing morpholine through diethylene glycol ammonolysis reaction, so that the conversion rate of diethylene glycol and the selectivity of the generated morpholine are improved.

Description

Technical Field

[0001] The present application relates to a method for preparing morpholine, belonging to the technical field of chemical engineering. Background Art

[0002] In China, with the gradual maturity of the technology for synthesizing morpholine by the low-pressure ammonolysis cyclization method of diethylene glycol, the output has also increased significantly, and the application research of morpholine has always been widely concerned. Due to its special chemical properties, morpholine is widely used in the fields of medicine, pesticides, coatings, rubber, and fine petrochemicals, and has currently become one of the fine chemical products with important commercial uses.

[0003] There are relatively many studies on morpholine catalysts. Air Products and Chemicals, Inc. of the United States disclosed a morpholine catalyst with r-Al2O3 as the carrier and Ni, Co, and Cr as the active components in Patent EP0036331; the Research Institute of Jilin Petrochemical Company disclosed a C2-C8 fatty alcohol amination catalyst with synthetic silicon and aluminum oxides as the carrier and Ni and Co as the active components in the patent with the publication number CN1316297A; Jilin Chemical Industry Corporation disclosed a morpholine catalyst with amorphous SiO2 prepared by acidifying natural bentonite as the carrier and Ni, Co, and Cu as the active components in the patent with the publication number CN1569327A, and the conversion rate of diethylene glycol was 99.1 - 99.6%, and the yield of morpholine reached 94.14%; BASF Company of Germany disclosed a synthetic ammoniation catalyst with Al2O3 as the carrier and Co, Ni, and Cu as the active components in the patent with the patent number DE3125662, and the morpholine yield was 86.06%; a catalyst with Al2O3 as the carrier and Cu, Zn, and Ni as the active components was disclosed in the patent with the publication number CN1915497A in China, and the conversion rate of diethylene glycol was as high as 98.5 - 99.5%, and the selectivity of morpholine was as high as 97.7 - 98.4%.

[0004] Solid catalysts have become the focus of researchers due to many advantages such as high activity, high selectivity, and easy separation. There are relatively few reports in the literature on solid catalysts used for catalyzing the ammoniation reaction of diethylene glycol. With the progress of technology and the improvement of people's environmental protection awareness, in chemical production, a solid catalyst with advantages such as recyclability and reusability. Summary of the Invention

[0005] Applying the catalyst in the preparation process of morpholine in the present application has great significance. The catalyst has good activity, high conversion rate of diethylene glycol and high selectivity of morpholine, and good stability.

[0006] According to one aspect of the present application, a method for preparing morpholine is provided, and the preparation method includes:

[0007] React a raw material containing diethylene glycol and liquid ammonia with a catalyst to obtain morpholine;

[0008] The catalyst includes a carrier and an active component supported on the carrier;

[0009] The carrier is a pure silica molecular sieve;

[0010] The active component includes Cu, Ni, and Co.

[0011] Optionally, the catalyst is Cu,Ni,Co / pure silica molecular sieve obtained by impregnating a pure silica molecular sieve by the excess impregnation method.

[0012] Optionally, the active component accounts for 20 - 40 wt% of the weight of the Cu,Ni,Co / pure silica molecular sieve.

[0013] Optionally, the content of the active component in the Cu,Ni,Co / pure silica molecular sieve independently selects any value from 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt% or a range value between any two of the above.

[0014] Optionally, the preparation method of the catalyst includes:

[0015] Mix a mixture containing a copper source, a nickel source, a cobalt source, a pure silica molecular sieve, and a solvent, stir, dry, and calcine to obtain Cu,Ni,Co / pure silica molecular sieve.

[0016] Optionally, the preparation method of the Cu,Ni,Co / pure silica molecular sieve includes the following steps:

[0017] (1) Mix a copper source, a nickel source, a cobalt source, and a pure silica molecular sieve in a solvent;

[0018] (2) Stir at high temperature until dry, dry, and calcine to obtain Cu,Ni,Co / pure silica molecular sieve.

[0019] Optionally, the copper source is selected from at least one of copper nitrate, copper sulfate, and copper chloride.

[0020] Optionally, the nickel source is selected from at least one of nickel nitrate, nickel sulfate, and nickel chloride.

[0021] Optionally, the cobalt source is selected from at least one of cobalt nitrate, cobalt sulfate, and cobalt chloride.

[0022] Optionally, the molar ratio of the nickel source to the copper source is 1:1 - 3, the molar amount of the nickel source is based on the molar amount of nickel element, and the molar amount of the copper source is based on the molar amount of copper element.

[0023] Optionally, the molar ratio of the nickel source to the copper source is independently selected from any value among 1:1, 1:2, and 1:3 or a range value between any two of the above.

[0024] Optionally, the molar ratio of the nickel source to the cobalt source is 1:0.1 to 0.5. The molar amount of the nickel source is based on the molar amount of nickel element, and the molar amount of the cobalt source is based on the molar amount of cobalt element.

[0025] Optionally, the molar ratio of the nickel source to the cobalt source is independently selected from any value among 1:0.1, 1:0.2, 1:0.3, 1:0.4, and 1:0.5 or a range value between any two of the above.

[0026] Optionally, the pure silica molecular sieve is selected from one of pure silica SBA-15, pure silica Silicalite-1, and pure silica MCM-41.

[0027] Optionally, the solvent is selected from at least one of ethanol and water.

[0028] Optionally, the temperature of the stirring is 60°C to 80°C, and the time of the stirring is 5 to 10 h.

[0029] Optionally, the temperature of the stirring is independently selected from any value among 60°C, 70°C, and 80°C or a range value between any two of the above.

[0030] Optionally, the time of the stirring is independently selected from any value among 5 h, 6 h, 7 h, 8 h, 9 h, and 10 h or a range value between any two of the above.

[0031] Optionally, the temperature of the drying is 80 to 120°C, and the time of the drying is 1 to 10 h.

[0032] Optionally, the temperature of the drying is independently selected from any value among 80°C, 90°C, 100°C, 110°C, and 120°C or a range value between any two of the above.

[0033] Optionally, the time of the drying is independently selected from any value among 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, and 10 h or a range value between any two of the above.

[0034] Optionally, the temperature of the calcination is 400 to 600°C, and the time of the calcination is 4 to 8 h.

[0035] Optionally, the temperature of the calcination is independently selected from any value among 400°C, 450°C, 500°C, 550°C, and 600°C or a range value between any two of the above.

[0036] Optionally, the calcination time is independently selected from any value among 4 h, 5 h, 6 h, 7 h, 8 h or a range value between any two of the above.

[0037] Optionally, the molar ratio of liquid ammonia to diethylene glycol is 1-6:1.

[0038] Optionally, the molar ratio of liquid ammonia to diethylene glycol is independently selected from any value among 1:1, 2:1, 3:1, 4:1, 5:1, 6:1 or a range value between any two of the above.

[0039] Optionally, the mass space velocity of the reaction is 0.1-1 h -1 .

[0040] Optionally, the mass space velocity of the reaction is independently selected from any value among 0.1 h -1 , 0.2 h -1 , 0.3 h -1 , 0.4 h -1 , 0.5 h -1 , 0.6 h -1 , 0.7 h -1 , 0.8 h -1 , 0.9 h -1 , 1 h -1 or a range value between any two of them.

[0041] Optionally, the temperature of the reaction is 100-300 °C.

[0042] Optionally, the temperature of the reaction is independently selected from any value among 100 °C, 120 °C, 140 °C, 160 °C, 180 °C, 200 °C, 220 °C, 240 °C, 260 °C, 280 °C, 300 °C or a range value between any two of the above.

[0043] Optionally, the pressure of the reaction is 1-3 MPa.

[0044] Optionally, the pressure of the reaction is independently selected from any value among 1 MPa, 2 MPa, 3 MPa or a range value between any two of the above.

[0045] The beneficial effects that can be produced by this application include:

[0046] 1) The catalyst Cu, Ni, Co / pure silica molecular sieve provided by this application can be applied to the reaction of preparing morpholine by the ammoniation of diethylene glycol, and can improve the conversion rate of diethylene glycol and the selectivity of the generated morpholine.

[0047] 2) The preparation method of the catalyst Cu, Ni, Co / pure silica molecular sieve provided by this application is stable, controllable and has good reproducibility.

[0048] 3) The method for preparing morpholine by the ammoniation of diethylene glycol provided in this application uses the solid acid catalyst provided in this application, with a fast reaction rate and high yield, and can be applied to large-scale production. Detailed implementation mode

[0049] The following describes this application in detail with reference to the embodiments, but this application is not limited to these embodiments.

[0050] Unless otherwise specified, the raw materials in the embodiments of this application are all purchased through commercial channels.

[0051] Among them, the gas chromatograph is a 7890B type gas chromatograph from Agilent.

[0052] The calculation methods of the conversion rate and selectivity in the embodiments of this application are as follows:

[0053] The calculation formulas of the conversion rate and selectivity in the embodiments of this application are as follows (taking the conversion rate of diethylene glycol as the evaluation index):

[0054] Diethylene glycol conversion rate = (number of carbon atoms of diethylene glycol at the beginning - number of carbon atoms of diethylene glycol in the product) * 100 / initial mole number of diethylene glycol

[0055] Morpholine selectivity = number of carbon atoms of morpholine * 100 / ∑(number of carbon atoms of morpholine + number of carbon atoms of other products).

[0056] BET characterization:

[0057] Use a Quantachrome QuadraSorb SI4 type physical adsorption instrument to characterize the specific surface area of catalyst 1 # for specific surface area characterization.

[0058] Example 1 Preparation of catalyst

[0059] Dissolve copper nitrate, nickel nitrate and cobalt nitrate in deionized water, pour it into pure silicon SBA-15 (the copper source, nickel source, and cobalt source account for 30% of the catalyst weight, nickel:copper molar ratio = 1:2, nickel:cobalt molar ratio = 1:0.2), stir at 70 °C for 6 hours, dry at 100 °C for 8 hours, and calcine in a muffle furnace at 500 °C for 6 hours to obtain catalyst 1 # .

[0060] According to the following steps, adjust the types, dosages of each raw material and reaction parameters to obtain a series of catalysts numbered 2 to 28, which are respectively denoted as catalyst 2 # ~ catalyst 28 # , as shown in Table 1 below:

[0061] Table 1

[0062]

[0063] The explanations of each column in Table 1 above are as follows:

[0064] Copper sources: copper nitrate (Cu1), copper sulfate (Cu2), copper chloride (Cu3).

[0065] Nickel sources: nickel nitrate (Ni1), nickel sulfate (Ni2), nickel chloride (Ni3).

[0066] Cobalt sources: cobalt nitrate (Co1), cobalt sulfate (Co2), cobalt chloride (Co3).

[0067] Pure silica molecular sieves: pure silica SBA-15 (Si1), pure silica Silicalite-1 (Si2), pure silica MCM-41 (Si3).

[0068] Comparative Example 1

[0069] Dissolve copper nitrate in deionized water, pour it into pure silica SBA-15 (the copper source accounts for 30% of the catalyst weight), stir at 70 °C for 6 hours, dry at 100 °C for 8 hours, and calcine in a muffle furnace at 500 °C for 6 hours to obtain the catalyst of Comparative Example 1. # Catalyst.

[0070] Comparative Example 2

[0071] Dissolve nickel nitrate in deionized water, pour it into pure silica SBA-15 (the nickel source accounts for 30% of the catalyst weight), stir at 70 °C for 6 hours, dry at 100 °C for 8 hours, and calcine in a muffle furnace at 500 °C for 6 hours to obtain the catalyst of Comparative Example 2. # Catalyst.

[0072] Comparative Example 3

[0073] Dissolve cobalt nitrate in deionized water, pour it into pure silica SBA-15 (the cobalt source accounts for 30% of the catalyst weight), stir at 70 °C for 6 hours, dry at 100 °C for 8 hours, and calcine in a muffle furnace at 500 °C for 6 hours to obtain the catalyst of Comparative Example 3. # Catalyst.

[0074] Comparative Example 4

[0075] Dissolve copper nitrate and nickel nitrate in deionized water, pour it into pure silica SBA-15 (the copper source and nickel source account for 30% of the catalyst weight, nickel:copper molar ratio = 1:2), stir at 70 °C for 6 hours, dry at 100 °C for 8 hours, and calcine in a muffle furnace at 500 °C for 6 hours to obtain the catalyst of Comparative Example 4. # Catalyst.

[0076] Comparative Example 5

[0077] Copper nitrate and cobalt nitrate were dissolved in deionized water, and then poured into pure silica SBA-15 (the copper source and cobalt source accounted for 30% of the catalyst weight, copper:cobalt molar ratio = 2:0.2). After stirring at 70 °C for 6 hours, it was dried at 100 °C for 8 hours, and then calcined in a muffle furnace at 500 °C for 6 hours to obtain Comparative Example 5 # catalyst

[0078] Comparative Example 6

[0079] Nickel nitrate and cobalt nitrate were dissolved in deionized water, and then poured into pure silica SBA-15 (the nickel source and cobalt source accounted for 30% of the catalyst weight, nickel:cobalt molar ratio = 1:0.2). After stirring at 70 °C for 6 hours, it was dried at 100 °C for 8 hours, and then calcined in a muffle furnace at 500 °C for 6 hours to obtain Comparative Example 6 # catalyst

[0080] Example 2

[0081] The catalyst was used for the reaction of ammoniating diethylene glycol to prepare morpholine

[0082] The catalysts 1 corresponding to serial numbers 1 to 28 prepared in Example 1 # ~Catalyst 28 # , were used for the ammoniation of diethylene glycol to prepare morpholine. At a reaction temperature of 230 °C, a reaction time of 4 hours, a reaction pressure of 1.8 Mpa, and a mass space velocity of 0.15 h -1 , with an ammonia-alcohol molar ratio of 5:1, the raw materials were fed into a fixed-bed reactor loaded with 3 g of the catalyst, and the condensation reaction was carried out to produce morpholine

[0083] After the reaction was stabilized, both the reaction raw materials and products were analyzed by gas-phase online chromatography. The reaction results are shown in Table 2

[0084] Gas chromatography characterization:

[0085] An Agilent 7890B gas chromatograph (FID detector, FFAP capillary column) was used to analyze the composition of the products of the ethylene glycol dehydration reaction

[0086] Table 2

[0087]

[0088]

[0089] As can be seen from Table 2, the Cu, Ni, Co / pure silica molecular sieve catalyst has higher conversion and selectivity than the catalysts prepared with single or two of Cu, Ni, Co as the active substances in the reaction of ammoniating to prepare morpholine

[0090] Example 3

[0091] The catalyst 1 prepared in Table 1 was used# The reaction of preparing morpholine by the ammoniation of diethylene glycol was carried out. Each reaction parameter was changed. After the reaction was stabilized, both the reaction raw materials and products were analyzed by gas-phase on-line chromatography. The reaction results are shown in Table 3.

[0092] Table 3

[0093]

[0094]

[0095] It can be seen from Table 3 that the reaction temperature has a great influence on the conversion rate of diethylene glycol.

[0096] As mentioned above, the above are only several embodiments of the present application, and do not impose any form of limitation on the present application. Although the present application is disclosed above with preferred embodiments, it is not intended to limit the present application. Any person skilled in the art, without departing from the scope of the technical solution of the present application, makes some changes or modifications using the technical content disclosed above, which are equivalent to equivalent implementation cases and all fall within the scope of the technical solution.

Claims

1. A preparation method of morpholine, characterized in that, The preparation method includes the following steps: Reacting a raw material containing diethylene glycol and liquid ammonia with a catalyst to obtain morpholine; The catalyst includes a carrier and an active component supported on the carrier; The carrier is a pure silica molecular sieve; The active component includes Cu, Ni, and Co.

2. The preparation method according to claim 1, characterized in that, The active component accounts for 20 - 40 wt% of the weight of the Cu, Ni, Co / pure silica molecular sieve.

3. The preparation method according to claim 1, characterized in that, The preparation method of the catalyst includes the following steps: Stirring, drying, and calcining a mixture containing a copper source, a nickel source, a cobalt source, a pure silica molecular sieve, and a solvent to obtain Cu, Ni, Co / pure silica molecular sieve; Preferably, the copper source is selected from at least one of copper nitrate, copper sulfate, and copper chloride; Preferably, the nickel source is selected from at least one of nickel nitrate, nickel sulfate, and nickel chloride; Preferably, the cobalt source is selected from at least one of cobalt nitrate, cobalt sulfate, and cobalt chloride.

4. The preparation method according to claim 3, characterized in that, The molar ratio of the nickel source to the copper source is 1:1 - 3. The molar amount of the nickel source is calculated based on the molar amount of nickel element, and the molar amount of the copper source is calculated based on the molar amount of copper element; Preferably, the molar ratio of the nickel source to the cobalt source is 1:0.1 - 0.

5. The molar amount of the nickel source is calculated based on the molar amount of nickel element, and the molar amount of the cobalt source is calculated based on the molar amount of cobalt element.

5. The preparation method according to claim 3, characterized in that, The pure silica molecular sieve is selected from one of pure silica SBA - 15, pure silica Silicalite - 1, and pure silica MCM - 41; Preferably, the solvent is selected from at least one of ethanol and water.

6. The preparation method according to claim 3, characterized in that, The temperature of the stirring is 60°C - 80°C, and the stirring time is 5 - 10 h; Preferably, the drying temperature is 80 - 120°C, and the drying time is 1 - 10 h.

7. The preparation method according to claim 3, characterized in that, The calcining temperature is 400 - 600°C, and the calcining time is 4 - 8 h.

8. The preparation method according to claim 1, characterized in that, The molar ratio of the liquid ammonia to the diethylene glycol is 1 - 6:1; Preferably, the mass space velocity of the reaction is 0.1 to 1 h -1 .

9. The preparation method according to claim 1, characterized in that, The reaction temperature is 100 - 300°C.

10. The preparation method according to claim 1, characterized in that, The reaction pressure is 1 - 3 MPa.

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