Process for the synthesis of bismorpholinodiethyl ether

Abstract

The application belongs to the field of compound synthesis and particularly relates to a synthesis process of bimorpholinyl diethyl ether; comprising the following processes: I, preparation of a hydrotalcite-like nanometer copper-based catalyst: comprising adopting copper nitrate, transition metal M nitrate, aluminum nitrate, precipitant A and precipitant B; II, continuous synthesis of bimorpholinyl diethyl ether: firstly, the hydrotalcite-like nanometer copper-based catalyst is loaded into a fixed bed reactor and activated by hydrogen reduction; raw materials composed of morpholine and diethylene glycol are prepared; the raw materials are punched into the fixed bed reactor for reaction, so that reaction liquid containing bimorpholinyl diethyl ether is obtained. The application solves the problems of low raw material conversion rate, poor product selectivity and short catalyst service life in the prior art.

Description

Technical Field

[0001] This invention belongs to the field of compound synthesis, specifically relating to a synthesis process of bismorpholino diethyl ether. Background Technology

[0002] Dimorpholino diethyl ether (DMDEE), as a single-component polyurethane blowing agent catalyst, has a wide range of applications in the polyurethane industry and other materials fields, and is considered one of the three major polyurethane catalysts.

[0003] Currently, the most widely used industrial process for synthesizing DMDEE is the morpholine and diethylene glycol dehydration method. However, catalysts, as the core of DMDEE synthesis, generally suffer from drawbacks such as low activity, poor selectivity, short lifespan, and high cost, thus becoming a key factor restricting the industrialization of this process.

[0004] CN116425702A discloses a copper-based catalyst modified with both alkaline earth metals and silver. This catalyst uses alkaline earth metals strontium or calcium and noble metal silver to modify the copper-based catalyst, and adds a biomass binder to improve the catalyst's structural stability. The catalyst is tested under conditions of a morpholine to diethylene glycol molar ratio of 2–4:1, a temperature of 180–260 °C, a pressure of 1.5–3.5 MPa, and a space velocity of 0.3–1.0 h⁻¹. -1 DMDEE was synthesized using a catalyst modified with the precious metal silver, resulting in relatively high cost. Furthermore, the DMDEE selectivity decreased to below 90% as the reaction progressed, indicating poor stability.

[0005] CN112920139B discloses a composite catalyst comprising an alumina-titanium oxide matrix and at least two metals selected from nickel, copper, cobalt, zinc, and lanthanum. DMDEE is synthesized using a morpholine to diethylene glycol molar ratio of 1:1 to 10, at a reaction temperature of 180 to 260 °C, and a pressure of 1.5 to 2.2 MPa. This composite catalyst is prepared by an impregnation method, which suffers from drawbacks such as easy loss and uneven distribution of active metals and a small specific surface area of ​​the support, making it difficult to guarantee a long catalyst life and good stability.

[0006] CN105289709B discloses a metal catalyst prepared using a mixture of nickel, copper, cobalt, chromium, iron, zinc, and lanthanum as active components via a positive drop-kneading extrusion method. DMDEE was synthesized at 240℃ and 5 MPa, showing a high selectivity of 82%. However, this catalyst suffers from problems such as high operating temperature, low activity, and poor selectivity.

[0007] In summary, the synthesis of DMDEE is hampered by problems such as low catalyst activity, poor selectivity, short catalyst lifetime, and high cost, which are key factors restricting its development. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a method for synthesizing bismorpholino diethyl ether.

[0009] To solve the above-mentioned technical problems, the present invention provides a method for synthesizing bismorpholino diethyl ether, comprising the following steps:

[0010] I. Preparation of hydrotalcite-like copper nano-catalysts

[0011] (1) Dissolve copper nitrate, transition metal M nitrate and aluminum nitrate in water to obtain a metal nitrate solution; the molar ratio of Cu to Al is 2 to 3:1, and the molar ratio of Cu to transition metal M is 6.5 to 20:1.

[0012] Dissolve precipitant A in water to obtain precipitant A solution;

[0013] Dissolve precipitant B in water to obtain precipitant B solution;

[0014] (2) First, add precipitant A solution to the container and heat precipitant A solution to the set precipitation temperature; then, under the condition of keeping warm, add metal nitrate solution and precipitant B solution to precipitant A solution in a dropwise manner (dropping time is about 0.5 to 3 hours);

[0015] After the dripping is complete, the mixture is stirred and aged under heat preservation conditions, then filtered. The resulting filter cake is washed, dried, calcined, and shaped (pressed into tablets) to obtain a hydrotalcite-like nano-copper-based catalyst.

[0016] The ratio of (the sum of the moles of Cu, Al and transition metal M) to (the sum of the moles of precipitant A and precipitant B) is 1:2.2 to 2.6.

[0017] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0018] First, the hydrotalcite-like copper nano-catalyst is loaded into a fixed-bed reactor and activated by hydrogen.

[0019] Prepare a starting material with a molar ratio of morpholine to diethylene glycol of 2–4:1; set the reaction temperature at 170–220℃, the pressure at 1–4.0 MPa, and the volume hourly space velocity at 0.3–0.5 h⁻¹. -1 The raw materials are fed into a fixed-bed reactor to react, thereby obtaining a reaction solution containing bismorpholino diethyl ether.

[0020] Volumetric space velocity = feed rate per unit time / catalyst volume.

[0021] An improvement to the synthesis method of the bismorpholino diethyl ether of the present invention:

[0022] The sum of the concentrations of Cu, Al, and transition metal M in the metal nitrate solution is 0.5–2.0 mol / L (preferably 1.0–2.0 mol / L);

[0023] The concentration of precipitant A solution is 1.0–2.0 mol / L (preferably 1.0–1.5 mol / L);

[0024] The concentration of precipitant B solution is 1.0–2.0 mol / L (preferably 1.0–1.5 mol / L).

[0025] As a further improvement to the synthesis method of the bismorpholino diethyl ether of the present invention:

[0026] The transition metal M is at least one (i.e., one or more combinations) selected from the transition metals nickel, iron, zinc, cobalt, and chromium.

[0027] As a further improvement to the synthesis method of the bismorpholino diethyl ether of the present invention:

[0028] Precipitator A is either sodium carbonate or potassium carbonate;

[0029] Precipitator B is either sodium hydroxide or potassium hydroxide.

[0030] As a further improvement to the synthesis method of the bismorpholino diethyl ether of the present invention:

[0031] In step one (2): the precipitation temperature is 25-80℃, the drying temperature is 50-110℃, the drying time is 6-36h, the calcination temperature is 400-600℃, and the calcination time is 3-6h.

[0032] Preferred conditions include: precipitation temperature 40–70℃; drying temperature 60–100℃; drying time 12–24h; calcination temperature 450–550℃; and calcination time 4–5h.

[0033] As a further improvement to the synthesis method of the bismorpholino diethyl ether of the present invention:

[0034] In step one (2), the stirring time is 0.5 to 1.0 hours and the aging time is 1.0 to 2.0 hours.

[0035] As a further improvement to the synthesis method of the bismorpholino diethyl ether of the present invention:

[0036] In the reduction and activation process of step two: the reduction temperature is 230-250℃, the reduction time is 3-6h, the hydrogen pressure is 0.5-2.0MPa, and the hydrogen volume hourly space velocity is 50-200mL / min.

[0037] In this invention, as a preferred embodiment:

[0038] The reduction temperature is 230–240℃; the hydrogen pressure is 1–2 MPa; the hydrogen volume hourly space velocity is 50–150 mL / min; and the reduction time is 3–4 h.

[0039] The molar ratio of morpholine to diethylene glycol in the raw materials is 3–4:1; the reaction temperature is 180–210℃; the reaction pressure is 1.5–3.5 MPa; and the volume hourly space velocity is 0.3–0.4 h⁻¹. -1 ;

[0040] In the metal nitrate solution of the present invention, a molar ratio of trivalent metal to (sum of divalent and trivalent metals) of 0.2 to 0.4 is preferred.

[0041] Under the conditions set by this invention, morpholine and diethylene glycol were continuously added to a fixed bed to carry out the reaction, and the stability of the catalyst was examined.

[0042] The beneficial effects of this invention are:

[0043] (1) This invention provides a hydrotalcite-like nano-copper-based catalyst, which is prepared by co-precipitation method and has the advantages of small metal grain size, high dispersion and good stability.

[0044] The catalyst of this invention does not involve precious metals, thus having the technical advantage of low cost.

[0045] This catalyst exhibits low reaction temperature, high activity, and good selectivity when used to synthesize bismorpholino diethyl ether.

[0046] (2) The hydrotalcite-like nano-copper-based catalyst provided by this invention can achieve a diethylene glycol conversion rate of over 99.4% and maintain DMDEE selectivity between 90.7% and 95.9% in a 3000h stability test, solving the problems of low raw material conversion rate, poor product selectivity and short catalyst life in the prior art.

[0047] From an economic perspective: using non-precious metal elements as the active component of the catalyst greatly reduces the production cost of the catalyst, while continuous processes can efficiently increase production capacity, which is conducive to industrial promotion. Detailed Implementation

[0048] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto:

[0049] Example 1

[0050] I. Preparation of hydrotalcite-like copper nano-catalysts

[0051] The molar ratio of Cu to Al was set to 2:1, and the molar ratio of Cu to transition metal M was set to 10:1; the molar ratio of metal to precipitant in the metal nitrate solution was set to 1:2.59.

[0052] Specifically as follows:

[0053] (1) Weigh 0.40 mol (96.64 g) copper nitrate trihydrate, 0.02 mol (5.82 g) nickel nitrate hexahydrate, 0.02 mol (8.08 g) ferric nitrate nonahydrate and 0.20 mol (75.03 g) aluminum nitrate nonahydrate, add water to make up to 320 mL, and prepare a 2.0 mol / L metal nitrate solution;

[0054] Weigh 0.10 mol (10.60 g) of anhydrous sodium carbonate and add water to prepare a 2.0 mol / L precipitant A solution;

[0055] Dissolve 1.56 mol (62.40 g) of sodium hydroxide in water to prepare a 2.0 mol / L precipitant B solution;

[0056] (2) Place the precipitant A solution in a four-necked flask and heat it to the precipitation temperature of 80°C. Then, under the condition of heat preservation (80°C), add the metal nitrate solution and the precipitant B solution dropwise to the precipitant A solution.

[0057] After the addition was complete (the addition time was about 1 hour), the mixture was stirred (stirring time was about 0.5 hours) and aged (aging time was about 1 hour) under the heat preservation condition. Then it was filtered, and the resulting filter cake was washed (washed with water until the pH was neutral), dried at 70°C for 24 hours, ground and sieved (through a 200-mesh sieve), pressed into tablets (diameter about 3-5 mm, thickness about 10 mm), and calcined at 500°C for 4 hours to obtain a hydrotalcite-like nano-copper-based catalyst.

[0058] In this case, (Al) 3+ +Fe 3+ ) / (Cu 2+ +Ni 2+ +Fe 3+ +Al 3+ The molar ratio is approximately 0.34.

[0059] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0060] 1) The hydrotalcite-like copper nano-catalyst was loaded into a fixed bed (catalyst loading amount was 40 mL) and activated by reduction with 2.0 MPa hydrogen at 240 °C for 4 h. The hydrogen volume flow rate was set to 100 mL / min during this process.

[0061] 2) Prepare a starting material with a molar ratio of morpholine to diethylene glycol of 4:1; set the reaction temperature at 200℃, the reaction pressure at 4.0 MPa, and the volume hourly space velocity at 0.4 h⁻¹. -1The reaction was carried out in a fixed-bed reactor, and the resulting products were analyzed for their content.

[0062] The diethylene glycol conversion rate was 99.8%, and the DMDEE selectivity was 95.9%. The impurities were N-hydroxyethylmorpholine, 1,2-dimorpholinylethane, N-ethylmorpholine, and the intermediate 4-[2-(2-hydroxyethoxy)ethyl]morpholine. The results are shown in Table 1.

[0063] illustrate:

[0064] Diethylene glycol conversion rate = (1 - unconverted diethylene glycol / total diethylene glycol in feed) × 100%

[0065] DMDEE selectivity = Amount of DMDEE generated / Diethylene glycol conversion rate × 100%

[0066] 3) After 3000 hours of continuous reaction, the diethylene glycol conversion rate remained above 99.4% and the DMDEE selectivity remained above 90.7%, indicating that the catalyst has excellent catalytic activity and stability.

[0067] Note: The purified DMDEE can be obtained by distilling the product obtained in this invention using conventional methods.

[0068] Example 2

[0069] I. Preparation of hydrotalcite-like copper nano-catalysts

[0070] The molar ratio of Cu to Al was set to 2:1, and the molar ratio of Cu to transition metal M was set to 10:1; the molar ratio of metal to precipitant in the metal nitrate solution was set to 1:2.26.

[0071] Specifically as follows:

[0072] (1) Weigh 0.40 mol copper nitrate trihydrate, 0.02 mol nickel nitrate hexahydrate, 0.02 mol zinc nitrate hexahydrate and 0.20 mol aluminum nitrate nonahydrate, and add water to make a 0.5 mol / L metal nitrate solution;

[0073] Weigh 0.10 mol of anhydrous potassium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0074] Take 1.344 mol of potassium hydroxide and add water to prepare a 1.0 mol / L precipitant B solution;

[0075] (2) Change the precipitation temperature to 60°C, the stirring time to about 1.0 h, the aging time to about 1.0 h, and the rest are the same as step (2) of Example 1.

[0076] In this case, Al 3+ / (Cu 2+ +Ni2+ +Zn 2+ +Al 3+ The molar ratio is approximately 0.31.

[0077] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0078] 1) The hydrotalcite-like copper nano-catalyst was loaded into a fixed bed (catalyst loading amount was 40 mL) and activated by reduction with 0.5 MPa hydrogen at 250 °C for 3 h. The hydrogen volume flow rate was set to 100 mL / min.

[0079] 2) Prepare a starting material with a molar ratio of morpholine and diethylene glycol of 4:1; set the reaction temperature at 170℃, the reaction pressure at 1.0 MPa, and the volume hourly space velocity at 0.3 h⁻¹. -1 The reaction was carried out in a fixed bed, and the content of the obtained products was analyzed. The reaction results are shown in Table 1.

[0080] Example 3

[0081] I. Preparation of hydrotalcite-like copper nano-catalysts

[0082] The molar ratio of Cu to Al was set to 2:1, and the molar ratio of Cu to transition metal M was set to 20:3; the molar ratio of metal to precipitant in the metal nitrate solution was set to 1:2.55.

[0083] (1) Weigh 0.40 mol copper nitrate trihydrate, 0.04 mol nickel nitrate nonahydrate, 0.02 mol cobalt nitrate hexahydrate and 0.20 mol aluminum nitrate nonahydrate, and add water to prepare a 1.0 mol / L metal nitrate solution;

[0084] Weigh 0.10 mol of anhydrous sodium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0085] Alternatively, prepare a 2.0 mol / L precipitant B solution by adding 1.584 mol of sodium hydroxide to water;

[0086] (2) The precipitation temperature was changed to 60°C, the stirring time was about 1.0 h, the aging time was about 2.0 h, and the rest were the same as step (2) of Example 1.

[0087] In this case, Al 3+ / (Cu 2+ +Ni 2+ +Co 2+ +Al 3+ The molar ratio is approximately 0.30.

[0088] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0089] 1) The hydrotalcite-like copper nano-catalyst was loaded into a fixed bed (catalyst loading amount was 40 mL) and activated by reduction with 1.0 MPa hydrogen at 250 °C for 3 h. The hydrogen volume flow rate was set to 100 mL / min.

[0090] 2) Prepare a starting material with a molar ratio of morpholine and diethylene glycol of 3:1; set the reaction temperature at 220℃, the reaction pressure at 4.0 MPa, and the volume hourly space velocity at 0.4 h⁻¹. -1 The reaction was carried out in a fixed bed, and the content of the obtained products was analyzed. The reaction results are shown in Table 1.

[0091] Example 4

[0092] I. Preparation of hydrotalcite-like copper nano-catalysts

[0093] The molar ratio of Cu to Al was set to 2:1, and the molar ratio of Cu to transition metal M was set to 20:3; the molar ratio of metal to precipitant in the metal nitrate solution was set to 1:2.59.

[0094] (1) Weigh 0.40 mol copper nitrate trihydrate, 0.04 mol nickel nitrate hexahydrate, 0.02 mol chromium nitrate nonahydrate and 0.20 mol aluminum nitrate nonahydrate, and add water to prepare a 1.0 mol / L metal nitrate solution;

[0095] Weigh 0.10 mol of anhydrous sodium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0096] Alternatively, take 1.608 mol of sodium hydroxide and add water to prepare a 2.0 mol / L precipitant solution B;

[0097] (2) Change the precipitation temperature to 60°C, and the rest is the same as step (2) of Example 1.

[0098] In this case, (Al) 3+ +Cr 3+ ) / (Cu 2+ +Ni 2+ +Al 3+ +Cr 3+ The molar ratio is approximately 0.33.

[0099] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0100] 1) The hydrotalcite-like copper nano-catalyst was loaded into a fixed bed (catalyst loading amount was 40 mL), and activated by reduction with 2.0 MPa hydrogen at 240 °C for 4 h. The hydrogen volume flow rate was set to 50 mL / min.

[0101] 2) Prepare a starting material with a molar ratio of morpholine and diethylene glycol of 2:1; set the reaction temperature at 220℃, the reaction pressure at 4.0 MPa, and the volume hourly space velocity at 0.3 h⁻¹. -1 The reaction was carried out in a fixed bed, and the content of the obtained products was analyzed. The reaction results are shown in Table 1.

[0102] Example 5

[0103] I. Preparation of hydrotalcite-like copper nano-catalyst is the same as in Example 1.

[0104] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0105] 1) The hydrotalcite-like copper nano-catalyst was loaded into a fixed bed (catalyst loading amount was 40 mL) and activated by reduction with 2.0 MPa hydrogen at 230 °C for 6 h. The hydrogen volume flow rate was set to 200 mL / min.

[0106] 2) Prepare a starting material with a molar ratio of morpholine and diethylene glycol of 3:1; set the reaction temperature at 220℃, the reaction pressure at 3.0 MPa, and the volume hourly space velocity at 0.5 h⁻¹. -1 The reaction was carried out in a fixed bed, and the content of the obtained products was analyzed. The reaction results are shown in Table 1.

[0107] Example 6

[0108] I. The hydrotalcite-like nano-copper-based catalyst is the same as in Example 2.

[0109] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0110] 1) The reduction and activation of the hydrotalcite-like copper nano-based catalyst is the same as in Example 2.

[0111] 2) Prepare a starting material with a molar ratio of morpholine and diethylene glycol of 4:1; set the reaction temperature at 210℃, the reaction pressure at 4.0 MPa, and the volume hourly space velocity at 0.5 h⁻¹. -1 The reaction was carried out in a fixed bed, and the content of the obtained products was analyzed. The reaction results are shown in Table 1.

[0112] Example 7

[0113] I. Preparation of hydrotalcite-like copper nano-catalysts

[0114] The molar ratio of Cu to Al was set to 2:1, and the molar ratio of Cu to transition metal M was set to 20:1; the molar ratio of metal to precipitant in the metal nitrate solution was set to 1:2.60.

[0115] (1) Weigh 0.40 mol copper nitrate trihydrate, 0.02 mol ferric nitrate nonhydrate and 0.20 mol aluminum nitrate nonhydrate, and add water to prepare a 1.0 mol / L metal nitrate solution;

[0116] Weigh 0.10 mol of anhydrous sodium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0117] Weigh 1.512 mol of sodium hydroxide and add water to prepare a 2.0 mol / L precipitant solution B;

[0118] (2) Place the precipitant A solution in a four-necked flask and heat it to the precipitation temperature of 25°C. Then, under the condition of keeping warm (25°C), add the metal nitrate solution and the precipitant B solution dropwise to the precipitant A solution.

[0119] After the addition was complete (the addition time was about 0.5 h), the mixture was stirred (stirring time was about 0.5 h) and aged (aging time was about 1 h) under the heat preservation condition. Then it was filtered, and the resulting filter cake was washed (washed with water until the pH was neutral), dried at 110 °C for 6 h, ground and sieved (through a 200-mesh sieve), pressed into tablets (diameter about 3-5 mm, thickness about 10 mm), and calcined at 400 °C for 6 h to obtain a hydrotalcite-like nano-copper-based catalyst.

[0120] In this case, (Al) 3+ +Fe 3+ ) / (Cu 2+ +Al 3+ +Fe 3+ The molar ratio is approximately 0.35.

[0121] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0122] 1) The reduction and activation of the hydrotalcite-like copper nano-catalyst is the same as in Example 1.

[0123] 2) Prepare a starting material with a molar ratio of morpholine and diethylene glycol of 2:1; set the reaction temperature at 190℃, the reaction pressure at 3.0 MPa, and the volume hourly space velocity at 0.3 h⁻¹. -1 The reaction was carried out in a fixed bed, and the content of the obtained products was analyzed. The reaction results are shown in Table 1.

[0124] Example 8

[0125] I. Preparation of hydrotalcite-like copper nano-catalysts

[0126] The molar ratio of Cu to Al was set to 3:1, and the molar ratio of Cu to transition metal M was set to 10:1; the molar ratio of metal to precipitant in the metal nitrate solution was set to 1:2.60.

[0127] (1) Weigh 0.60 mol copper nitrate trihydrate, 0.06 mol ferric nitrate nonhydrate and 0.20 mol aluminum nitrate nonhydrate, and add water to prepare a 1.0 mol / L metal nitrate solution;

[0128] Weigh 0.10 mol of anhydrous sodium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0129] Weigh 2.136 mol of sodium hydroxide and add water to prepare a 2.0 mol / L precipitant B solution;

[0130] (2) The time for the metal nitrate solution and precipitant B to be dropped together was extended to 3 hours, and the calcination was changed to: calcination at 600°C for 3 hours, and the rest was the same as step (2) of Example 1.

[0131] In this case, (Al) 3+ +Fe 3+ ) / (Cu 2+ +Fe 3+ +Al 3+ The molar ratio is approximately 0.30.

[0132] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0133] 1) The reduction and activation of the hydrotalcite-like copper nano-based catalyst is the same as in Example 2.

[0134] 2) Prepare a starting material with a molar ratio of morpholine and diethylene glycol of 3:1; set the reaction temperature at 190℃, the reaction pressure at 2.0 MPa, and the volume hourly space velocity at 0.4 h⁻¹. -1 The reaction was carried out in a fixed bed, and the content of the obtained products was analyzed. The reaction results are shown in Table 1.

[0135] Example 9

[0136] I. Preparation of hydrotalcite-like copper nano-catalyst is the same as in Example 7.

[0137] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0138] 1) The reduction and activation of the hydrotalcite-like copper nano-catalyst is the same as in Example 7.

[0139] 2) Prepare a starting material with a molar ratio of morpholine and diethylene glycol of 2:1; set the reaction temperature at 190℃, the reaction pressure at 4.0 MPa, and the volume hourly space velocity at 0.3 h⁻¹. -1 The reaction was carried out in a fixed-bed reactor, and the content of the resulting products was analyzed. The reaction results are shown in Table 1.

[0140] Example 10

[0141] I. Preparation of hydrotalcite-like copper nano-catalyst is the same as in Example 8.

[0142] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0143] 1) The reduction and activation of the hydrotalcite-like nano-copper-based catalyst is the same as in Example 8.

[0144] 2) Prepare a starting material with a molar ratio of morpholine and diethylene glycol of 3:1; set the reaction temperature at 190℃, the reaction pressure at 4.0 MPa, and the volume hourly space velocity at 0.4 h⁻¹. -1 The reaction was carried out in a fixed-bed reactor, and the content of the resulting products was analyzed. The reaction results are shown in Table 1.

[0145] Comparative Example 1

[0146] I. Preparation of hydrotalcite-like copper nano-catalysts

[0147] The molar ratio of Cu to Al was set to 2:1; the molar ratio of metal to precipitant in the metal nitrate solution was 1:2.57.

[0148] (1) Weigh 0.40 mol of copper nitrate trihydrate and 0.20 mol of aluminum nitrate nonahydrate, and add water to prepare a 1.0 mol / L metal nitrate solution;

[0149] Weigh 0.10 mol of anhydrous sodium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0150] Weigh 1.44 mol of sodium hydroxide and add water to prepare a 2.0 mol / L precipitant solution B;

[0151] (2) Place the precipitant A solution in a four-necked flask and heat it to the precipitation temperature of 60°C. Then, under the condition of heat preservation (60°C), add the metal nitrate solution and the precipitant B solution dropwise to the precipitant A solution.

[0152] After the addition was complete (the addition time was about 1 hour), the mixture was stirred (stirring time was about 0.5 hours) and aged (aging time was about 1 hour) under the heat preservation condition. Then it was filtered, and the resulting filter cake was washed (washed with water until the pH was neutral), dried at 50°C for 36 hours, ground and sieved (through a 200-mesh sieve), pressed into tablets (diameter about 3-5 mm, thickness about 10 mm), and calcined at 500°C for 4 hours to obtain a hydrotalcite-like nano-copper-based catalyst.

[0153] In this case, Al 3+ / (Cu 2+ +Al 3+ The molar ratio is approximately 0.33.

[0154] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0155] 1) The reduction and activation of the hydrotalcite-like copper nano-catalyst is the same as in Example 1.

[0156] 2) The evaluation process for the hydrotalcite-like copper nano-catalyst is the same as in Example 1, and the reaction results are shown in Table 1.

[0157] Comparative Example 2

[0158] I. Preparation of hydrotalcite-like nickel-based nanocatalysts

[0159] The molar ratio of Ni to Al was set to 2:1; the molar ratio of metal to precipitant in the metal nitrate solution was 1:2.57.

[0160] (1) Weigh 0.40 mol nickel nitrate hexahydrate and 0.20 mol aluminum nitrate nonahydrate, and add water to prepare a 1.0 mol / L metal nitrate solution;

[0161] Weigh 0.10 mol of anhydrous sodium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0162] Weigh 1.44 mol of sodium hydroxide and add water to prepare a 2 mol / L precipitant B solution;

[0163] (2) Change the precipitation temperature to 60°C, and the rest is the same as step (2) of Example 1.

[0164] In this case, Al 3+ / (Ni 2+ +Al 3+ The molar ratio is approximately 0.33.

[0165] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0166] 1) The reduction and activation of the hydrotalcite-like nano-nickel-based catalyst is the same as in Example 1.

[0167] 2) The evaluation process for the hydrotalcite-like nano-nickel-based catalyst is the same as in Example 1, and the reaction results are shown in Table 1.

[0168] Comparative Example 3

[0169] I. Preparation of hydrotalcite-like cobalt nano-catalysts

[0170] The molar ratio of Co to Al was set to 2:1; the molar ratio of metal to precipitant in the metal nitrate solution was 1:2.57; the main active component was changed from nickel to cobalt, that is, 0.40 mol nickel nitrate hexahydrate was replaced with 0.40 mol cobalt nitrate hexahydrate, and the rest of the preparation process was the same as in Comparative Example 2.

[0171] In this case, Al 3+ / (Co 2+ +Al 3+ The molar ratio is approximately 0.33.

[0172] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0173] 1) The reduction and activation of the hydrotalcite-like nano-cobalt-based catalyst is the same as in Example 1.

[0174] 2) The evaluation process of the hydrotalcite-like nano-cobalt-based catalyst is the same as in Example 1, and the reaction results are shown in Table 1.

[0175] Comparative Example 4

[0176] I. Preparation of hydrotalcite-like copper nano-catalysts

[0177] The molar ratio of Cu to Al was set to 2:1; the molar ratio of Cu to transition metal M was set to 2:1; and the molar ratio of metal to precipitant in the metal nitrate solution was set to 1:2.53.

[0178] (1) Weigh 0.40 mol copper nitrate trihydrate, 0.20 mol nickel nitrate hexahydrate and 0.20 mol aluminum nitrate nonahydrate, and add water to prepare a 1.0 mol / L metal nitrate solution;

[0179] Weigh 0.10 mol of anhydrous sodium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0180] Alternatively, prepare a 2.0 mol / L precipitant B solution by adding 1.92 mol of sodium hydroxide to water;

[0181] (2) Change the precipitation temperature to 60°C, and the rest is the same as step (2) of Example 1.

[0182] In this case, Al 3+ / (Cu 2+ +Ni 2+ +Al 3+ The molar ratio is 0.25.

[0183] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0184] 1) The reduction and activation of the hydrotalcite-like copper nano-catalyst is the same as in Example 1.

[0185] 2) The evaluation process for the hydrotalcite-like copper nano-catalyst is the same as in Example 1, and the reaction results are shown in Table 1.

[0186] Comparative Example 5

[0187] I. Preparation of hydrotalcite-like copper nano-catalysts

[0188] The molar ratio of Cu to Al was set to 2:1; the molar ratio of Cu to transition metal M was set to 2:1; and the molar ratio of metal to precipitant in the metal nitrate solution was set to 1:2.53.

[0189] (1) Weigh 0.40 mol copper nitrate trihydrate, 0.20 mol cobalt nitrate hexahydrate and 0.20 mol aluminum nitrate nonahydrate, and add water to prepare a 1.0 mol / L metal nitrate solution;

[0190] Weigh 0.10 mol of anhydrous sodium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0191] Alternatively, prepare a 2.0 mol / L precipitant B solution by adding 1.92 mol of sodium hydroxide to water;

[0192] (2) Change the precipitation temperature to 60°C, and the rest is the same as step (2) of Example 1.

[0193] In this case, Al 3+ / (Cu 2+ +Co 2+ +Al 3+ The molar ratio is 0.25.

[0194] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0195] 1) The reduction and activation of the hydrotalcite-like copper nano-catalyst is the same as in Example 1.

[0196] 2) The evaluation process for the hydrotalcite-like copper nano-catalyst is the same as in Example 1, and the reaction results are shown in Table 1.

[0197] Comparative Example 6

[0198] The catalyst was prepared according to the "impregnation method" described in CN112920139B, and the metal composition and molar ratio in the catalyst were the same as those in Example 1 (Cu2Ni). 0.1 Fe 0.1 Al1". Details are as follows:

[0199] I. Preparation of Copper-Based Catalysts by Impregnation Method

[0200] Weigh 0.40 mol of copper nitrate trihydrate, 0.02 mol of nickel nitrate hexahydrate, and 0.02 mol of ferric nitrate nonahydrate, and add water to prepare a 2.0 mol / L metal nitrate solution. Separately weigh 0.10 mol of pretreated alumina support; place it in an Erlenmeyer flask containing the metal nitrate solution and immerse for 6 hours, then drain to obtain the filtrate and catalyst intermediate. Dry the catalyst intermediate at 140℃ for 12 hours, then calcine it in a muffle furnace at 500℃ for 4 hours, and allow it to cool naturally to obtain the catalyst precursor. Place the obtained catalyst precursor in the filtrate and repeat the above operation to finally obtain the shaped catalyst.

[0201] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0202] 1) The reduction and activation of the copper-based catalyst are the same as in Example 1.

[0203] 2) The evaluation process for the copper-based catalyst is the same as in Example 1, and the reaction results are shown in Table 1.

[0204] Comparative Example 7

[0205] The catalyst was prepared according to the "positive drop-kneading extrusion method" described in CN105289709B, with the same metal composition and molar ratio as in Example 1 (Cu2Ni). 0.1 Fe 0.1 Al1". Details are as follows:

[0206] I. Preparation of Copper-Based Catalysts by Positive Drop-Kneading Extrusion Method

[0207] Weigh out 0.40 mol of copper nitrate trihydrate, 0.02 mol of nickel nitrate hexahydrate, and 0.02 mol of ferric nitrate nonahydrate, and dilute with water to prepare a 2.0 mol / L metal nitrate solution;

[0208] Another method involves preparing a 20% wt alkaline solution by adding 0.54 mol of sodium carbonate to water. The sodium carbonate solution is continuously added to the metal nitrate solution at 40–60 °C until the pH of the mixed solution reaches 8. The solution is then filtered, and the filter cake is washed three times with deionized water. After drying, the filter cake is calcined at 500 °C for 3 hours to obtain a mixture of metal oxides. This mixture is then mixed with 13.60 g of boehmite and an aqueous nitric acid solution, extruded, and dried at room temperature for 1–10 days, then dried at 150 °C for 24 hours, and finally calcined at 530 °C for 5 hours to obtain the final shaped catalyst.

[0209] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0210] 1) The reduction and activation of the copper-based catalyst are the same as in Example 1.

[0211] 2) The evaluation process for the copper-based catalyst is the same as in Example 1, and the reaction results are shown in Table 1.

[0212] Comparative Example 8

[0213] I. Preparation of copper-based catalysts

[0214] The molar ratio of Cu to Al was set to 1:1, the molar ratio of Cu to transition metal M was set to 5:1, and the molar ratio of metal to precipitant in the metal nitrate solution was set to 1:2.71.

[0215] (1) Weigh 0.20 mol copper nitrate trihydrate, 0.04 mol nickel nitrate hexahydrate, 0.04 mol ferric nitrate nonhydrate and 0.20 mol aluminum nitrate nonhydrate, and add water to prepare a 1.0 mol / L metal nitrate solution;

[0216] Weigh 0.10 mol of anhydrous sodium carbonate and add water to prepare a 1.0 mol / L precipitant A solution;

[0217] Weigh 1.20 mol of sodium hydroxide and add water to prepare a 2.0 mol / L precipitant B solution;

[0218] (2) Change the precipitation temperature to 60°C, and the rest is the same as step (2) of Example 1.

[0219] In this case, (Al) 3+ +Fe 3+ ) / (Cu 2+ +Ni 2+ +Fe 3+ +Al 3+ The molar ratio is 0.50.

[0220] II. Continuous Synthesis of Bimorpholino Diethyl Ether

[0221] 1) The reduction and activation of the copper-based catalyst are the same as in Example 1.

[0222] 2) The evaluation process for the copper-based catalyst is the same as in Example 1, and the reaction results are shown in Table 1.

[0223] Table 1 Performance evaluation results of different catalysts

[0224]

[0225]

[0226] Finally, it should be noted that the above examples are merely some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments and many variations are possible. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A method for synthesizing bismorpholino diethyl ether, characterized in that... The process includes the following: I. Preparation of hydrotalcite-like copper nanoparticle catalysts: (1) Dissolve copper nitrate, transition metal M nitrate and aluminum nitrate in water to obtain metal nitrate solution; the molar ratio of Cu to Al is 2~3:1, and the molar ratio of Cu to transition metal M is 6.5~20:1; Dissolve precipitant A in water to obtain precipitant A solution; Dissolve precipitant B in water to obtain precipitant B solution; The transition metal M is at least one of the transition metals nickel, iron, zinc, cobalt, and chromium; Precipitator A is either sodium carbonate or potassium carbonate; Precipitator B is either sodium hydroxide or potassium hydroxide; In a metal nitrate solution, the molar ratio of trivalent metal to (the sum of divalent and trivalent metals) is 0.2 to 0.

4. (2) First, add precipitant A solution to the container and heat precipitant A solution to the set precipitation temperature; Then, under the condition of heat preservation, the metal nitrate solution and the precipitant B solution were added to the precipitant A solution dropwise; After the dripping is complete, the mixture is stirred and aged under heat preservation conditions, then filtered. The resulting filter cake is washed, dried, calcined, and shaped to obtain a hydrotalcite-like nano-copper-based catalyst. The ratio of (the sum of the moles of Cu, Al, and transition metal M) to (the sum of the moles of precipitant A and precipitant B) is 1:2.2~2.

6. II. Continuous Synthesis of Bismorpholino Diethyl Ether: First, the hydrotalcite-like copper nano-catalyst is loaded into a fixed-bed reactor and activated by hydrogen. Prepare a starting material with a molar ratio of morpholine to diethylene glycol of 2–4:1; set the reaction temperature at 170–220 °C, the pressure at 1–4.0 MPa, and the volume hourly space velocity at 0.3–0.5 h⁻¹. -1 The raw materials are fed into a fixed-bed reactor to react, thereby obtaining a reaction solution containing bismorpholino diethyl ether.

2. The method for synthesizing bismorpholino diethyl ether according to claim 1, characterized in that: The sum of the concentrations of Cu, Al, and transition metal M in the metal nitrate solution is 0.5~2.0 mol / L; The concentration of precipitant A solution is 1.0~2.0 mol / L; The concentration of precipitant B solution is 1.0~2.0 mol / L.

3. The method for synthesizing bismorpholino diethyl ether according to claim 2, characterized in that: In step one (2): the precipitation temperature is 25~80℃, the drying temperature is 50~110℃, the drying time is 6~36h, the calcination temperature is 400~600℃, and the calcination time is 3~6h.

4. The method for synthesizing bismorpholino diethyl ether according to claim 3, characterized in that: In step one (2), the stirring time is 0.5 to 1.0 hours and the aging time is 1 to 2 hours.

5. The method for synthesizing bismorpholino diethyl ether according to claim 4, characterized in that: In the reduction and activation process of step two: the reduction temperature is 230~250℃, the hydrogen pressure is 0.5~2.0MPa, the hydrogen volume hourly space velocity is 50~200mL / min, and the reduction time is 3~6h.

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