Catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine as well as preparation and application of catalyst

Abstract

The invention discloses a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine as well as preparation and application of the catalyst. The method comprises the following steps: mixing an active component soluble salt and an auxiliary agent soluble salt, and dissolving to obtain a soluble salt solution; dropwise adding the soluble salt solution and the precipitant solution into the bismuth-containing carrier solution under stirring for precipitation reaction, wherein the pH value of the reaction solution is controlled to be 9-11 in the precipitation process; and after the precipitation is finished, aging, filtering, washing, drying, roasting and carrying out reduction activation to prepare the catalyst for synthesizing piperazine and N-hydroxyethyl piperazine in one step by using hydroxyethyl ethylenediamine. The problems that an existing catalyst contains highly toxic Cr, the reaction temperature is larger than or equal to 200 DEG C, and stability is poor are solved. The prepared catalyst does not contain a toxic element Cr, piperazine and N-hydroxyethyl piperazine can be efficiently synthesized in one step, and the catalyst is good in stability, low in dosage and low in production cost.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of catalyst for synthesizing piperazine and N-hydroxyethyl piperazine, specifically to a kind of catalyst for hydroxyethyl ethylenediamine one-step synthesis piperazine and N-hydroxyethyl piperazine and its preparation and application. BACKGROUND

[0002] Piperazine molecular formula C4H 10 N2, it is six-membered heterocyclic ring containing two symmetrical nitrogen atoms, unique structure makes it become the key intermediate of medicine and fine chemical industry.In recent years, our country demand surges, market gap is big, price is high and quantity is short.N-hydroxyethyl piperazine (C6H 14 N2O) molecular structure includes piperazine ring and hydroxyethyl, is a kind of derivative of piperazine.It is an important chemical intermediate, often used for synthesis of medicine, pesticide and surfactant and other fine chemicals.Taking hydroxyethyl ethylenediamine (AEEA) as raw material, by catalyzing its dehydration cyclization preparation piperazine process is the current more efficient synthesis method, it has the advantages of mild reaction condition, high yield, product easy to refine etc., but the shortcoming is also inadmissible: reaction network is complex, reaction condition is harsh, catalyst is easy to lose, in Cu-Cr system catalyst with higher activity to this kind of reaction, Cr is toxic element, further popularization and application cause the trouble, and taking hydroxyethyl ethylenediamine as raw material one-step synthesis piperazine and N-hydroxyethyl piperazine synthesis method is less reported.

[0003] The existing document 1 (Chinese invention patent application with publication number CN106984343A) discloses a Ni-Cu-Fe-Cr-Zn / alkali-activated bentonite. The active metals, including Ni, Cu, Fe, Cr and Zn, are impregnated in the alkali-activated bentonite through a fixed bed reactor evaluation. The conversion rate of the prepared catalyst is >95%, and the total selectivity of piperazine and N-methyl piperazine is >95%. However, it has the disadvantages of containing Cr, high temperature, and lack of stability data. The existing document 2 (Chinese invention patent application with publication number CN1687041A) discloses a Ni-Cu-Cr-Mn-Zn-Fe / γ-Al2O3-diatomite for synthesizing piperazine in a continuous process. The conversion rate of hydroxyethyl ethylenediamine is higher than about 86% under the optimal catalyst at 220℃ and 3.5MPa. However, it has the disadvantages of containing Cr, harsh conditions, and low conversion rate. The existing document 3 (Chinese invention patent application with publication number CN114247449A) discloses a catalyst for synthesizing piperazine from hydroxyethyl ethylenediamine, its preparation method and application. The catalyst mainly contains Cu and Cr as active components, and is synthesized by a precipitation method. The precursor is dried and calcined to form a catalyst for synthesizing piperazine from hydroxyethyl ethylenediamine in a fixed bed continuous catalytic process. The optimal catalyst activity can reach 99% under the reaction conditions of 250℃ and 3MPa, and the selectivity of piperazine is close to 100% with good stability. However, it has the disadvantages of containing Cr and high temperature and pressure. The existing document 4 (Chinese invention patent application with publication number CN107051560A) discloses a N-β-hydroxyethyl ethylenediamine cyclization catalyst and its preparation method for synthesizing piperazine and N-methyl piperazine. The active substance of the catalyst is Cu1Cr0.1-2La0.1-0.8P0.05-0.6, and the carrier is Al2O3. The catalyst precursor is synthesized by a combustion method, and the precursor is dried and calcined to form a catalyst for synthesizing piperazine from hydroxyethyl ethylenediamine in a fixed bed continuous catalytic process. The catalyst activity can reach more than 90% under the reaction conditions of 200℃ and 1MPa, and the sum of the selectivity of piperazine and N-methyl piperazine is more than 90%. However, it has the disadvantages of containing Cr, high safety risk of combustion method, lack of stability data, and difficulty in scale-up.

[0004] Through comprehensive analysis of the above existing research, it is found that the common problems are: all containing highly toxic Cr, high environmental pressure; reaction temperature ≥200℃, most of the technical pressure ≥3MPa, harsh conditions; lack of or no long-term stability data of the catalyst. SUMMARY

[0005] The application aims to provide a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine and its preparation and application, solve the problems of existing catalysts containing toxic Cr, reaction temperature ≥ 200 ℃ and poor stability, and the prepared catalyst does not contain toxic element Cr, can efficiently synthesize piperazine and N-hydroxyethyl piperazine in one step, and has good catalyst stability, low dosage and low production cost.

[0006] In order to achieve the above-mentioned purpose, the application provides a preparation method of a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine, which comprises the following steps: (1) mixing and dissolving active component soluble salt and additive soluble salt to obtain a soluble salt solution; under stirring, the soluble salt solution and a precipitant solution are added dropwise into a bismuth-containing carrier solution to perform a precipitation reaction, and the pH value of the reaction solution is controlled to be 9-11 during the precipitation process; (2) after the precipitation is completed, aging, filtration, washing, drying, calcination and reduction activation are performed to obtain the catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine; The metal elements in the active component soluble salt are Ni and Cu; the metal elements in the additive soluble salt are any one and two or more of Zn, Mn, La, Fe, V, In and Co; the bismuth-containing carrier in the bismuth-containing carrier solution is prepared by adding bismuth salt solution into nano carrier microparticles, stirring and impregnating at room temperature, drying at 90-150 ℃, calcining at 300-600 ℃, and grinding into powder; and the nano carrier microparticles are any one or two or more of ZrO2, CeO2, Al2O3, SiO2, hydroxyapatite (Ca 10 (PO4)6(OH)2, and nano attapulgite (ATP).

[0007] Preferably, in step (1), the precipitant in the precipitant solution is any one or two or more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonium bicarbonate and ammonia water; and the active component soluble salt and the additive soluble salt are nitrate, sulfate, chloride or acetate.

[0008] Preferably, in step (1), the mass ratio of the total mass of the metal elements in the active component to the total mass of the metal elements in the additive is (20-100):(0-20); and the mass ratio of Ni to Cu is (10-60):(10-40).

[0009] Preferably, in step (1), in the bismuth-containing carrier, the mass fraction of bismuth element in the nano carrier microparticles is 1%-5%; and the mass ratio of the total mass of the metal elements in the soluble salt solution to the mass of the nano carrier microparticles in the bismuth-containing carrier solution is (30-85):(15-70).

[0010] Preferably, in step (1), the bismuth salt in the bismuth salt solution is bismuth nitrate or bismuth chloride; the concentration of the precipitant solution is 0.5-4 mol / L; and the total concentration of the soluble salt solution is 0.1-1.0 mol / L.

[0011] Preferably, in step (1), the temperature of the precipitation reaction is room temperature-90°C; and in step (2), the temperature of the aging is room temperature-90°C, and the time is 2-24 h.

[0012] Preferably, in step (2), the drying temperature is 90-150°C, and the time is 12-24 h; and the calcination temperature is 350-550°C, and the time is 2-8 h.

[0013] Preferably, in step (2), the reduction activation is carried out in high-purity hydrogen or hydrogen-nitrogen mixed gas at a pressure of normal pressure-3.0 MPa and a temperature of 400-600°C for 3-6 h.

[0014] The application provides a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine, which is prepared by the preparation method.

[0015] The application provides application of the catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine in synthesis of piperazine and N-hydroxyethyl piperazine.

[0016] The catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine, its preparation and application solve the problems of existing catalysts, such as containing toxic Cr, a reaction temperature ≥ 200°C, and poor stability, and have the following advantages: 1. The metal Bi is doped on the surface of the nano-carrier microparticles by impregnation and calcination, and due to the binding effect of Bi, the carrier and the supported metal can establish a stronger metal-carrier strong interaction, the stability of the catalyst is increased, the catalyst is not prone to inactivation phenomena such as agglomeration, sintering or loss during the reaction process, and thus the service life of the catalyst is prolonged.

[0017] 2. The introduction of the auxiliary metal can increase the oxygen vacancy sites on the surface of the catalyst, enhance the adsorption and activation capacity of the catalyst for reactants, improve the hydroxyl dehydrogenation, amination and hydrogenation capacity of the catalyst, make the catalyst synthesize piperazine and N-hydroxyethyl piperazine efficiently, and thus improve the catalyst activity. By adjusting the types, proportions of the auxiliary metal and changing the process conditions, the synthesis ratio of piperazine and N-hydroxyethyl piperazine can be changed. The interaction between the auxiliary metal and the catalyst carrier and active components can enhance the structural stability of the catalyst, inhibit sintering, agglomeration and loss of the active components of the catalyst at high temperatures, and thus improve the stability of the catalyst.

[0018] 3、The supported NiCu alloy catalyst system provided by the application does not contain toxic element Cr, and under milder reaction conditions, the catalyst can be used to efficiently synthesize piperazine and N-hydroxyethylpiperazine in one step in a continuous flow fixed bed or an intermittent reaction kettle, and has good stability, low catalyst dosage and low production cost. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 A result graph of the cycle stability of the catalyst 3 prepared from Example 3 in a high-pressure kettle according to the application.

[0020] Figure 2 A result graph of the cycle stability of the comparative catalyst 3 prepared from Comparative Example 3 in a high-pressure kettle according to the application.

[0021] Figure 3 A result graph of the cycle stability of the catalyst 3 prepared from Example 3 in a tubular fixed bed reactor according to the application.

[0022] Figure 4 A result graph of the cycle stability of the comparative catalyst 3 prepared from Comparative Example 3 in a tubular fixed bed reactor according to the application. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0024] Example 1 A preparation method of a catalyst for one-step synthesis of piperazine and N-hydroxyethylpiperazine from hydroxyethyl ethylenediamine, the method comprising: (1) To a container, 100 mL of deionized water was added, 0.35 g of bismuth nitrate was added, and 9.0 g of nitric acid was added as a solubilizer. After the bismuth nitrate was dissolved, 5.0 g of aluminum oxide nano-carrier microparticles was added, and the mixture was stirred at room temperature for 6 h, dried at 120°C for 12 h to remove excess water, and calcined at 450°C for 4 h. The mixture was ground into powder to obtain 3% Bi-Al2O3 carrier. 6.0 g of the 3% Bi-Al2O3 carrier was diluted with 24 mL of deionized water to 5 times (the total mass of the solution after dilution was 5 times that of the 3% Bi-Al2O3 carrier, and the same below), to obtain a carrier solution; 9.91 g of nickel nitrate and 7.61 g of copper nitrate were mixed and dissolved in 700 mL of deionized water to prepare a 0.1 mol / L salt solution; 7.42 g of sodium carbonate and 2.8 g of sodium hydroxide were mixed and dissolved in 140 mL of deionized water to prepare a mixed alkali aqueous solution containing 0.5 mol / L sodium carbonate and 0.5 mol / L sodium hydroxide. The 0.1 mol / L salt solution and the mixed alkali aqueous solution were added dropwise into the carrier solution to perform a co-precipitation reaction, and the temperature of the co-precipitation reaction was controlled at 90°C, and the pH of the co-precipitation reaction was adjusted to about 10 with the mixed alkali aqueous solution.

[0025] (2) After the reaction was completed, the mixture was aged at 90°C for 2 h, filtered, washed until the pH of the filtrate was about 7, dried at 150°C for 12 h, calcined at 350°C in an air atmosphere for 8 h, and ground and sieved into 60-100 mesh particles to obtain a catalyst, which was recorded as 20Ni20Cu-3% Bi-Al2O3.

[0026] For catalyst performance evaluation, the catalyst of Example 1 was activated as follows: under normal pressure, the catalyst was reduced and activated in a 20% H2-N2 mixed gas atmosphere at 100 mL / min and 400°C for 6 h to obtain an activated catalyst 1.

[0027] Example 2 A method for preparing a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine, the method comprising: (1) 100 mL of deionized water was added to a container, 0.58 g of bismuth nitrate was added, 15.0 g of nitric acid was added as a solubilizer, after the bismuth nitrate was dissolved, 5.0 g of silica nano-carrier microparticles was added, stirred at room temperature for 1 h, removed the excess water, dried at 90°C for 24 h, calcined at 600°C for 3 h, ground into powder to obtain 5% Bi-SiO2 carrier. 3.0 g of 5% Bi-SiO2 carrier was diluted with 57 mL of deionized water to 20 times to obtain a carrier solution; 26.75 g of nickel nitrate, 4.45 g of copper nitrate and 4.72 g of magnesium nitrate were mixed and dissolved in 130 mL of deionized water to prepare a 1.0 mol / L salt solution; 20.14 g of sodium carbonate was dissolved in 190 mL of deionized water to prepare a 1 mol / L sodium carbonate aqueous solution, the 1.0 mol / L salt solution and the 1 mol / L sodium carbonate aqueous solution were added to the carrier solution together for co-precipitation, and the pH was controlled at about 9 at room temperature.

[0028] (2) After the reaction was completed, the temperature was increased to 50°C and aged for 8 h, then filtered, washed until the pH of the filtrate was about 7, dried at 90°C for 24 h, calcined at 550°C in air for 2 h, ground and sieved into 60-100 mesh particles to obtain the catalyst, which is denoted as 54Ni12Cu4Mg-5%Bi-SiO2.

[0029] For catalyst performance evaluation, the catalyst of Example 2 was activated, specifically: under normal pressure, reduced and activated at 600°C in a H2 atmosphere at 100 mL / min for 4 h to obtain the activated catalyst 2.

[0030] Example 3 A method for preparing a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine, the method comprising: (1) To a container, 100 mL of deionized water was added, 0.58 g of bismuth nitrate was added, and 15.0 g of nitric acid was added as a solubilizer. After the bismuth nitrate was dissolved, 5.0 g of nano-attapulgite (referred to as ATP) nano-carrier particles were added, and the mixture was stirred at room temperature for 1 h. The excess water was removed, and the mixture was dried at 90°C for 24 h and calcined at 600°C for 3 h. The mixture was ground into powder to obtain 3% Bi-ATP carrier. 3.0 g of the 3% Bi-ATP carrier was diluted with 27 mL of deionized water to 10 times to obtain a carrier solution. 14.87 g of nickel nitrate, 7.61 g of copper nitrate, 2.28 g of zinc nitrate, 2.78 g of vanadium nitrate, 2.47 g of cobalt nitrate, and 3.62 g of iron nitrate were mixed and dissolved in 120 mL of deionized water to prepare a 1 mol / L salt solution. 19.08 g of sodium carbonate was dissolved in 180 mL of deionized water to prepare a 1 mol / L sodium carbonate aqueous solution. The 1 mol / L salt solution and the 1 mol / L sodium carbonate aqueous solution were added dropwise into the carrier solution to perform a co-precipitation reaction, and the precipitation temperature was controlled at 50°C. The pH was controlled at about 9 using the 1 mol / L sodium carbonate aqueous solution.

[0031] (2) After the reaction was completed, the mixture was aged at 50°C for 4 h, and then filtered and washed until the pH of the filtrate was about 7. The mixture was dried at 110°C for 20 h and calcined at 450°C in an air atmosphere for 4 h. The mixture was ground and sieved to obtain particles with a size of 60-100 mesh to obtain a catalyst, which was denoted as 30Ni20Cu5Zn5V5Co5Fe-3%Bi-ATP.

[0032] For catalyst performance evaluation, the catalyst of Example 3 was activated as follows: under normal pressure, the catalyst was reduced and activated at 450°C in a 20% H2-N2mixed gas atmosphere at a flow rate of 100 mL / min for 6 h to obtain an activated catalyst 3.

[0033] Example 4 A method for preparing a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine, the method comprising: (1) To a container, 100 mL of deionized water was added, 0.3 g of bismuth chloride was added, and 12.0 g of hydrochloric acid was added to assist the dissolution, after the bismuth chloride was dissolved, 5.0 g of aluminum oxide nano-carrier microparticles was added, stirred at room temperature for 10 h, removed the excess water, dried at 150°C for 8 h, calcined at 300°C for 6 h, ground into powder to obtain 4% Bi-Al2O3 carrier. 2.5 g of 4% Bi-Al2O3 carrier was diluted to 15 times with 35 mL of deionized water to obtain a carrier solution; 8.96 g of nickel sulfate, 15.73 g of copper sulfate, 2.20 g of zinc sulfate, 1.66 g of manganese sulfate and 2.39 g of cobalt sulfate were mixed and dissolved in 240 mL of deionized water to prepare a 0.5 mol / L salt solution; 24.84 g of potassium carbonate was dissolved in 180 mL of deionized water to prepare a 1 mol / L potassium carbonate aqueous solution, the 0.5 mol / L salt solution and the 1 mol / L potassium carbonate aqueous solution were added to the carrier solution to carry out the co-precipitation reaction, and the precipitation temperature was controlled at 80°C, and the pH of the co-precipitation reaction was controlled at about 9 by the potassium carbonate aqueous solution.

[0034] (2) After the reaction was completed, the aging was carried out at 80°C for 4 h, then the filter cake was washed until the pH of the filtrate was about 7, dried at 120°C for 15 h, calcined at 400°C in air for 6 h, and then ground and sieved into 60-100 mesh particles to obtain the catalyst, which was recorded as 20Ni40Cu5Zn5Mn5Co-4% Bi-Al2O3.

[0035] For catalyst performance evaluation, the catalyst of Example 4 was activated, specifically: under normal pressure, 100 mL / min, 500°C reduction activation in 20% H2-N2 mixed gas atmosphere for 4 h to obtain the activated catalyst 4.

[0036] Example 5 A method for preparing a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine, which is basically the same as Example 1, the difference is that: (1) Into a container, 100 mL of deionized water was added, 0.23 g of bismuth nitrate was added, and 5.0 g of nitric acid was added as a solubilizer. After the bismuth nitrate was dissolved, 5.0 g of zirconium oxide nano-carrier microparticles was added, and the same operation as in Example 1 was performed to obtain 2% Bi-ZrO2 carrier. 4.5 g of 2% Bi-ZrO2 carrier was diluted 10 times with 40.5 mL of deionized water to obtain a carrier solution; 10.86 g of nickel nitrate, 7.61 g of copper nitrate, 5.56 g of vanadium nitrate, and 3.62 g of iron nitrate were weighed and dissolved in 180 mL of deionized water to prepare a 0.5 mol / L salt solution; 19.32 g of potassium carbonate was weighed and dissolved in 140 mL of deionized water to prepare a 1 mol / L potassium carbonate aqueous solution, and the 0.5 mol / L salt solution and the 1 mol / L potassium carbonate aqueous solution were added to the carrier solution to perform a co-precipitation reaction, and the precipitation temperature was controlled at 80°C, and the pH of the co-precipitation reaction was controlled at about 9.5 using the potassium carbonate aqueous solution.

[0037] (2) After the reaction was completed, the pH of the filtrate was adjusted to about 7 by washing at 80°C for 4 h, and then the product was dried at 120°C for 12 h and calcined at 450°C in an air atmosphere for 4 h, and then ground and sieved to obtain a catalyst having a particle size of 60-100 mesh, which was denoted as 20Ni20Cu10V5Fe-2% Bi-ZrO2.

[0038] For catalyst performance evaluation, the catalyst of Example 5 was activated as follows: under normal pressure, the catalyst was reduced and activated at 100 mL / min in a 20% H2-N2 mixed gas atmosphere at 500°C for 4 h to obtain an activated catalyst 5.

[0039] Example 6 A method for preparing a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine was substantially the same as in Example 2, except that: (1) 5.0 g of silica nano-carrier microparticles was replaced with 5.0 g of hydroxyapatite (HAP for short) nano-carrier microparticles, and the same operation as in Example 2 was performed to obtain a 5% Bi-HAP carrier. 2.5 g of 5% Bi-HAP carrier was diluted 20 times with 47.5 mL of deionized water to obtain a carrier solution; 8.48 g of nickel acetate, 6.29 g of copper acetate, 1.74 g of indium acetate, 2.11 g of cobalt acetate, and 1.40 g of lanthanum acetate were mixed and dissolved in 160 mL of deionized water to prepare a 0.5 mol / L salt solution; 16.60 g of ammonium bicarbonate was dissolved in 110 mL of deionized water to prepare a 2 mol / L ammonium bicarbonate aqueous solution, and the 0.5 mol / L salt solution and the 2 mol / L ammonium bicarbonate aqueous solution were added to the carrier solution to perform a co-precipitation reaction, and the pH was controlled at about 9.0 using the 2 mol / L ammonium bicarbonate aqueous solution at room temperature.

[0040] (2) After the reaction is completed, aging is performed at room temperature for 24 h, filtration is performed, washing is performed until the pH of the filtrate is about 7, drying is performed at 150 °C for 10 h, grinding and sieving are performed into 60-100 mesh particles after calcination in an air atmosphere at 400 °C for 6 h, and a catalyst is obtained, which is recorded as 20Ni40Cu5In5Co5La-5% Bi-HAP.

[0041] For catalyst performance evaluation, the catalyst of Example 6 is activated, specifically: reduction activation is performed at 450 °C for 6 h at 100 mL / min under normal pressure in a 20% H2-N2mixed gas atmosphere to obtain an activated catalyst 6.

[0042] Example 7 A preparation method of a catalyst for one-step synthesis of piperazine and N-hydroxyethylpiperazine from hydroxyethyl ethylenediamine is basically the same as that in Example 3, except that: (1) 4.5 g of 3% Bi-ATP carrier is diluted to 10 times with 40.5 mL of deionized water to obtain a carrier solution. 4.05 g of nickel chloride, 7.2 g of copper chloride, 2.05 g of zinc chloride, 1.8 g of manganese chloride and 4.24 g of magnesium chloride are weighed and dissolved in 200 mL of deionized water to prepare a 0.5 mol / L salt solution; 13.8 g of potassium carbonate and 5.6 g of potassium hydroxide are weighed and dissolved in 200 mL of deionized water to prepare a mixed aqueous alkali solution containing 0.5 mol / L potassium carbonate and 0.5 mol / L potassium hydroxide, the 0.5 mol / L salt solution and the mixed aqueous alkali solution are added to the carrier solution at the same time, a coprecipitation reaction is performed, the precipitation temperature is controlled to be 70 °C, and the pH of the coprecipitation reaction is controlled to be about 11 by using the mixed aqueous alkali solution.

[0043] (2) After the reaction is completed, aging is performed at 70 °C for 4 h, filtration is performed, washing is performed until the pH of the filtrate is about 7, drying is performed at 110 °C for 20 h, grinding and sieving are performed into 60-100 mesh particles after calcination in an air atmosphere at 500 °C for 4 h, and a catalyst is obtained, which is recorded as 10Ni30Cu5Zn5Mn5Mg-3% Bi-ATP.

[0044] For catalyst performance evaluation, the catalyst of Example 7 is activated, specifically: reduction activation is performed at 450 °C for 3 h at 100 mL / min under normal pressure in a 20% H2-N2mixed gas atmosphere to obtain an activated catalyst 7.

[0045] Example 8 A preparation method of a catalyst for one-step synthesis of piperazine and N-hydroxyethylpiperazine from hydroxyethyl ethylenediamine is basically the same as that in Example 4, except that: (1) Take 0.08 g of bismuth chloride, 3.0 g of hydrochloric acid as a solvent, and perform the same operation as in Example 4 to obtain a 1% Bi-Al2O3 carrier. Dilute 7.0 g of the 1% Bi-Al2O3 carrier with 28 mL of deionized water to 5 times to obtain a carrier solution. Take 4.48 g of nickel sulfate, 3.93 g of copper sulfate, 2.20 g of zinc sulfate, and 1.54 g of manganese sulfate, mix them in 500 mL of deionized water to prepare a 0.1 mol / L salt solution; take 10.21 g of potassium carbonate, dissolve it in 74 mL of deionized water to prepare a 1 mol / L potassium carbonate aqueous solution, and drop the 0.1 mol / L salt solution and the 1 mol / L potassium carbonate aqueous solution into the carrier solution to perform a co-precipitation reaction, and control the precipitation temperature to be 90°C and the pH of the potassium carbonate aqueous solution to be about 9.

[0046] (2) After the reaction is completed, age at 90°C for 12 h, perform suction filtration, wash until the pH of the filtrate is about 7, dry at 110°C for 20 h, calcine at 400°C in an air atmosphere for 6 h, and then grind and sieve to obtain 60-100 mesh particles to obtain a catalyst, which is recorded as 10Ni10Cu5Zn5Mn-1% Bi-Al2O3.

[0047] For catalyst performance evaluation, the catalyst of Example 8 is activated as follows: reduce and activate the catalyst at 500°C for 3 h under normal pressure in a 20% H2-N2 mixed gas atmosphere to obtain an activated catalyst 8.

[0048] Example 9 A method for preparing a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine is basically the same as that of Example 8, except that: (1) Adjust 5.0 g of alumina nano-carrier particles to 2.5 g of cerium oxide nano-carrier particles and 2.5 g of alumina nano-carrier particles, perform the same operation as in Example 8 to obtain a 1% Bi-CeO2-Al2O3 carrier. Dilute 4.5 g of the 1% Bi-CeO2-Al2O3 carrier with 85.5 mL of deionized water to 20 times to obtain a carrier solution; take 14.87 g of nickel nitrate, 3.8 g of copper nitrate, 1.39 g of indium nitrate, 2.47 g of cobalt nitrate, and 5.34 g of magnesium nitrate, mix them in 200 mL of deionized water to prepare a 0.5 mol / L salt solution; take 34.18 g of 25wt% ammonia water, add 100 mL of deionized water, and prepare a 4.0 mol / L ammonia water solution, and drop the 0.5 mol / L salt solution and the 4.0 mol / L ammonia water solution into the carrier solution to perform a co-precipitation reaction, and control the pH of the ammonia water solution to be about 9 at room temperature.

[0049] (2) After the reaction is completed, ammonia is aged at 90°C until the system water vapor pH is about 7, and then filtered, washed until the filtrate pH is about 7, dried at 120°C for 12h, calcined at 500°C in air for 4h, and then ground and sieved into 60-100 mesh particles to obtain a catalyst, which is recorded as 30Ni10Cu5In5Co5Mg-1% Bi-CeO2-Al2O3.

[0050] For catalyst performance evaluation, the catalyst of Example 9 is activated as follows: under normal pressure, in a pure H2atmosphere, reduction activation is carried out at 80mL / min and 550°C for 3h to obtain an activated catalyst 9.

[0051] Example 10 A preparation method of a catalyst for one-step synthesis of piperazine and N-hydroxyethylpiperazine from hydroxyethyl ethylenediamine is basically the same as that of Example 5, except that: (1) 5.0g of zirconium oxide nano carrier particles is adjusted to 5.0g of cerium oxide nano carrier particles, and the same operation as in Example 5 is performed to obtain a 2% Bi-CeO2carrier. 2.0g of the 2% Bi-CeO2carrier is diluted to 10 times with 18 mL of deionized water to obtain a carrier solution; 24.78g of nickel nitrate, 3.8g of copper nitrate, 2.28g of zinc nitrate, 3.62g of iron nitrate, 2.78g of vanadic nitrate, and 5.34g of magnesium nitrate are weighed and dissolved in 150 mL of deionized water to prepare a 1.0mol / L salt solution; 23.32g of sodium carbonate is weighed and dissolved in 220 mL of deionized water to prepare a 1.0mol / L sodium carbonate aqueous solution; the 1.0mol / L salt solution and the 1.0mol / L sodium carbonate aqueous solution are added dropwise into the carrier solution to perform a coprecipitation reaction, and the precipitation temperature is controlled at 60°C and the pH is controlled at about 9 by the sodium carbonate aqueous solution.

[0052] (2) After the reaction is completed, ammonia is aged at 60°C for 8h, and then filtered, washed until the filtrate pH is about 7, dried at 120°C for 12h, calcined at 500°C in air for 4h, and then ground and sieved into 60-100 mesh particles to obtain a catalyst, which is recorded as 50Ni10Cu5Zn5Co5Fe5V5Mg-2% Bi-CeO2.

[0053] For catalyst performance evaluation, the catalyst of Example 10 is activated as follows: under normal pressure, in a pure H2atmosphere, reduction activation is carried out at 80mL / min and 500°C for 3h to obtain an activated catalyst 10.

[0054] Comparative Example 1 A preparation method of a catalyst for one-step synthesis of piperazine and N-hydroxyethylpiperazine from hydroxyethyl ethylenediamine is basically the same as that of Example 3, except that: In step (1), except that no Cu element is added, the rest of the element measurement and preparation method is the same as that of Example 3, and the catalyst of Comparative Example 1 is prepared, which is recorded as 30Ni5Zn5V5Co5Fe-3%Bi-ATP.

[0055] For catalyst performance evaluation, the catalyst of Comparative Example 1 is activated, specifically: under normal pressure, in a 20% H2-N2mixed gas atmosphere, reduction activation is carried out at 100 mL / min and 450°C for 6h to obtain the activated comparative catalyst 1.

[0056] Comparative Example 2 The preparation method of a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine is basically the same as that of Example 4, and the difference lies in that: In step (1), except that no Ni element is added, the rest of the element measurement and preparation method is the same as that of Example 4, and the catalyst of Comparative Example 2 is prepared, which is recorded as 40Cu5Zn5Mn5Co-4%Bi-Al2O3.

[0057] For catalyst performance evaluation, the catalyst of Comparative Example 2 is activated, specifically: in a 20% H2-N2mixed gas atmosphere, reduction activation is carried out at 100 mL / min and 500°C for 4h to obtain the activated comparative catalyst 2.

[0058] Comparative Example 3 The preparation method of a catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine is basically the same as that of Example 3, and the difference lies in that: In step (1), the surface of the ATP nanocarrier particle is not doped with metallic bismuth, and the rest of the element measurement and preparation method is the same as that of Example 3, and the catalyst of Comparative Example 3 is prepared, which is recorded as 30Ni20Cu5Zn5V5Co5Fe-ATP.

[0059] For catalyst performance evaluation, the catalyst of Comparative Example 3 is activated, specifically: under normal pressure, in a 20% H2-N2mixed gas atmosphere, reduction activation is carried out at 100 mL / min and 450°C for 6h to obtain the activated comparative catalyst 3.

[0060] Experimental Example 1 tests the performance of the catalyst in an autoclave The reaction of one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine is carried out in an autoclave with a volume of 100 mL, 25 g of 20% hydroxyethyl ethylenediamine aqueous solution is added, 0.5 g of the activated catalyst of Examples 1-10 and the activated comparative catalyst of Comparative Examples 1-3 is taken respectively, hydrogen is replaced, and the pressure is charged to 1.5 MPa, and the reaction is stirred at 170°C for 3h. The test results are shown in Table 1.

[0061] Table 1 Test performance of the activated catalyst of Examples 1-10 and the activated comparative catalyst of Comparative Examples 1-3 From the results of Table 1, it can be seen that after modification of the NiCu alloy catalyst with rare earth metals and alkaline earth metal additives, the hydroxyl dehydrogenation, amination and hydrogenation abilities of the active metal can be improved by synergistic effect, and the selectivity of piperazine in the product can be improved; by adjusting the types and proportions of the additives, the synthesis ratio of piperazine to N-hydroxyethylpiperazine in the product can be changed; the ATP carrier contains elements such as Mg and Fe, which can further improve the catalyst activity and product selectivity in cooperation with the active metal and the additive, and the price is low; from Comparative Example 1 and Comparative Example 2, it can be seen that the nickel-copper alloy catalyst has higher activity and product selectivity than the pure nickel-based or copper-based catalyst; from Comparative Example 3, it can be seen that after modification of the carrier surface with bismuth, the corresponding activity and selectivity of the catalyst are not reduced.

[0062] Experimental Example 2: Test of the influence of the activation catalyst 3 on the catalytic performance in a high-pressure kettle Hydroxyethyl ethylenediamine was used to synthesize piperazine and N-hydroxyethylpiperazine under different conditions. The reaction was carried out in a high-pressure kettle with a volume of 100 mL, 25 g-50 g of hydroxyethyl ethylenediamine aqueous solution with a certain concentration was added, 0.06 g-1.0 g of the activation catalyst 3 of Example 3 was taken, hydrogen was replaced for three times, and the pressure was charged to 0.5-5 MPa, and the reaction was stirred at 150-200 ℃ for 3-8 h. The results are shown in Table 2.

[0063] Table 2: Test of the influence of the activation catalyst 3 on the catalytic performance From the results of Table 2, it can be seen that the activation catalyst 3 of Example 3 has excellent activity for the one-step reaction of hydroxyethyl ethylenediamine to synthesize piperazine and N-hydroxyethylpiperazine, and it is more beneficial to improve the selectivity of piperazine under the conditions of low temperature, low concentration and high pressure. By adjusting the reaction process conditions, the synthesis ratio of piperazine to N-hydroxyethylpiperazine can be adjusted.

[0064] Experimental Example 3: Test of the cycle stability of the activation catalyst 3 of Example 3 in a high-pressure kettle The specific operation method for testing the cycle stability of the activation catalyst 3 of Example 3 is as follows: the kettle cycle stability of the catalyst 3 was investigated in a high-pressure kettle with a volume of 100 mL. 25 g of 20% hydroxyethyl ethylenediamine aqueous solution was added each time, hydrogen was replaced, the pressure was charged to 1.5 MPa, and the reaction was stirred at 170 ℃ for 3 h. Fresh activation catalyst 0.03 g was added each time except for the first reaction which added 0.375 g of fresh activation catalyst 3. The results are shown in Figure 1 The results of the test of the cycle stability of the activation catalyst 3 prepared in Example 3 in a high-pressure kettle are shown in the graph of Figure 1It can be seen that after ten cycles of batch circulation, the conversion rate of hydroxyethyl ethylenediamine and the sum of the selectivities of piperazine and N-hydroxyethyl piperazine are both ≥90%, and the catalyst activity decreases slowly.

[0065] Experiment 4 tested the cycle stability of Comparative Catalyst 3 activated in an autoclave. The specific operating method for testing the cycle stability of the activated comparative catalyst 3 in Comparative Example 3 is the same as the method for testing the cycle stability of the activated catalyst 3 in Example 3 above. The results are as follows: Figure 2 The figure shown is a graph illustrating the cycle stability of the activated comparative catalyst 3 prepared in Comparative Example 3, tested in a high-pressure reactor according to the present invention. Figure 2 It was found that the surface of the activated comparative catalyst 3 prepared in Comparative Example 3 was not modified with metallic bismuth, and its stability was very poor. After the fifth batch cycle, the conversion rate of hydroxyethyl ethylenediamine dropped to below 70%, and the sum of the selectivity of piperazine and N-hydroxyethyl piperazine did not decrease significantly.

[0066] Experiment 5: Testing the performance of the catalyst under different conditions in a tubular fixed-bed reactor. 1. Conversion and selectivity were tested at a hydrogen-to-ester ratio of 100:1. The specific operation for testing the conversion and selectivity of the catalyst prepared in Example 3 at a hydrogen-to-ester ratio of 100:1 was as follows: 5g of the catalyst prepared in Example 3 (30Ni20Cu5Zn5V5Co5Fe-3%Bi-ATP, unactivated) was weighed and loaded into the isothermal section of a tubular fixed-bed reactor, with the remainder filled with inert SiC. The catalyst was reduced and activated at 450℃ for 10h in a 3MPa, 10% H2-N2 mixed atmosphere. After the temperature of the tubular fixed-bed reactor dropped to 180℃, the pressure was increased to 5.0 MPa using high-purity H2. A 20% aqueous solution of hydroxyethyl ethylenediamine was then pumped into the tubular fixed-bed reactor via a feed pump at a hydrogen-to-ester ratio of 100:1 (volume ratio of hydrogen to hydroxyethyl ethylenediamine, as described below) and a feed mass hourly space velocity (WHSV) of 1.0 h⁻¹. -1 The results of sampling and analysis after 80 hours of reaction were as follows: the conversion rate of hydroxyethyl ethylenediamine was 99.0%, the selectivity of piperazine was 90.3%, the selectivity of N-hydroxyethyl piperazine was 6.5%, and the sum of the selectivities was 96.8%.

[0067] 2. Conversion and selectivity were tested at a hydrogen-to-ester ratio of 50:1. The specific operation for testing the conversion and selectivity of the catalyst prepared in Example 3 at a hydrogen-to-ester ratio of 50:1 was as follows: 5g of the catalyst prepared in Example 3 (30Ni20Cu5Zn5V5Co5Fe-3%Bi-ATP, unactivated) was weighed and loaded into the isothermal section of a tubular fixed-bed reactor, with the remainder filled with inert SiC. The catalyst was reduced and activated at 450℃ for 10h in a 20% H2-N2 mixed atmosphere at atmospheric pressure. After the temperature of the tubular fixed-bed reactor dropped to 170℃, the pressure was increased to 3.0 MPa using high-purity H2. A 20% aqueous solution of hydroxyethyl ethylenediamine was then pumped into the tubular fixed-bed reactor via a feed pump at a hydrogen-to-ester ratio of 50:1 and a feed mass hourly space velocity (WHSV) of 0.5 h⁻¹. -1 The results of sampling and analysis after 80 hours of reaction were as follows: the conversion rate of hydroxyethyl ethylenediamine was 99.2%, the selectivity of piperazine was 86.3%, the selectivity of N-hydroxyethyl piperazine was 7.5%, and the sum of the selectivities was 93.8%.

[0068] 3. Cyclic stability was tested at a hydrogen-to-ester ratio of 5:1. The specific method for testing the cycle stability of the catalyst prepared in Example 3 is as follows: 5g of the catalyst prepared in Example 3 (30Ni20Cu5Zn5V5Co5Fe-3%Bi-ATP, unactivated) was weighed and loaded into the isothermal section of a tubular fixed-bed reactor, with the remainder filled with inert SiC. The catalyst was reduced and activated at 450℃ for 10h in a 20% H2-N2 mixed atmosphere at atmospheric pressure. After the temperature of the tubular fixed-bed reactor dropped to 150℃, the pressure was increased to 3.0 MPa using high-purity H2. A 20% aqueous solution of hydroxyethyl ethylenediamine was then pumped into the tubular fixed-bed reactor via a feed pump, with a hydrogen-to-ester ratio of 5:1 and a feed mass hourly space velocity of 0.1 h⁻¹. -1 .like Figure 3 The figure shown is a graph illustrating the cycle stability of catalyst 3 prepared in Example 3, tested in a tubular fixed-bed reactor according to the present invention. Figure 3 As can be seen, after catalysis by catalyst 3 of the present invention, the average conversion rate of hydroxyethyl ethylenediamine is 96.4%, the average selectivity of piperazine is 88.5%, and the average selectivity of N-hydroxyethyl piperazine is 6.2%, with the sum of the two selectivities being 94.7%. No significant decrease was observed after 500 hours of reaction. It is evident that catalyst 3 prepared in Example 3 of the present invention has excellent stability.

[0069] Experiment 6: Testing the performance of the catalyst in Comparative Example 3 in a tubular fixed-bed reactor. The operating method for examining the cycle stability of the comparative catalyst 3 prepared in Comparative Example 3 was the same as the specific method used to test the cycle stability of the catalyst prepared in Example 3 in Experimental Example 5 above. The results are as follows: Figure 4 The figure shows the results of testing the cycle stability of the comparative catalyst 3 prepared in Comparative Example 3 in a tubular fixed-bed reactor. (From...) Figure 4It was found that although the catalyst of Comparative Example 3 and the catalyst of Example 3 have the same components and support, if the surface of the support is not modified by metallic bismuth, the stability of the comparative catalyst 3 is very poor, which is consistent with the conclusion of the stability of the batch circulation.

[0070] Based on the analysis of the above experimental results, it is concluded that the present invention, through impregnation and calcination, incorporates metallic Bi onto the surface of nanoparticles. Due to the binding effect of Bi, the carrier particles and the supported active metal establish stronger metal-carrier interactions, increasing the catalyst's stability and making it less prone to deactivation phenomena such as agglomeration, sintering, or loss during the reaction process, thereby extending the catalyst's lifespan and stability. The evaluation results from both the batch reactor and fixed-bed reactors show that the fixed-bed process is more conducive to improving the selectivity of piperazine.

[0071] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A process for the preparation of a catalyst for the one-step synthesis of piperazine and N-hydroxyethylpiperazine from hydroxyethylethylenediamine, characterized in that, The method comprises: (1) mixing active component soluble salt and auxiliary soluble salt, dissolving to obtain soluble salt solution; under stirring, dropping the soluble salt solution and precipitant solution into bismuth-containing carrier solution to carry out precipitation reaction, controlling pH value of reaction solution to be 9-11 during precipitation process; (2) after precipitation is completed, aging, filtering, washing, drying, roasting, reduction activation to obtain catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine; Metal elements in the active component soluble salt are Ni and Cu; Metal elements in the auxiliary soluble salt are any one and two or more of Zn, Mn, La, Fe, V, In and Co; The bismuth-containing carrier in the bismuth-containing carrier solution is prepared by adding nano carrier microparticles into bismuth salt solution, stirring and impregnating at room temperature, drying at 90-150 DEG C, roasting at 300-600 DEG C and grinding into powder; The nano carrier microparticles are any one or two or more of ZrO2, CeO2, Al2O3, SiO2, hydroxyapatite and nano attapulgite.

2. The production method according to claim 1, characterized by, In step (1), the precipitant in the precipitant solution is any one or two or more of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonium bicarbonate and ammonia water; the active component soluble salt and the auxiliary soluble salt are nitrate, sulfate, chloride or acetate.

3. The preparation method according to claim 1, characterized in that, In step (1), the mass ratio of total mass of metal elements in the active component to total mass of metal elements in the auxiliary is (20-100):(0-20); the mass ratio of Ni to Cu is (10-60):(10-40).

4. The production method according to claim 1, characterized by, In step (1), in the bismuth-containing carrier, bismuth element accounts for 1-5% of mass of nano carrier microparticles; the mass ratio of total mass of metal elements in the soluble salt solution to mass of nano carrier microparticles in the bismuth-containing carrier solution is (30-85):(15-70).

5. The method of claim 1, wherein, In step (1), the bismuth salt in the bismuth salt solution is bismuth nitrate or bismuth chloride; the concentration of the precipitant solution is 0.5-4 mol / L; the total concentration of the soluble salt solution is 0.1-1.0 mol / L.

6. The method of claim 1, wherein, In step (1), the temperature of the precipitation reaction is room temperature-90 DEG C; in step (2), the temperature of the aging is room temperature-90 DEG C and the time is 2-24 h.

7. The preparation method according to claim 1, characterized in that, In step (2), the temperature of the drying is 90-150 DEG C and the time is 12-24 h; the temperature of the roasting is 350-550 DEG C and the time is 2-8 h.

8. The method of claim 1, wherein, In step (2), the reduction activation is carried out in high-purity hydrogen or hydrogen-nitrogen mixed gas at normal pressure-3.0 MPa at 400-600 DEG C for 3-6 h.

9. The catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine prepared by the preparation method in any one of claims 1-8.

10. Application of the catalyst for one-step synthesis of piperazine and N-hydroxyethyl piperazine from hydroxyethyl ethylenediamine in claim 1 in synthesis of piperazine and N-hydroxyethyl piperazine.

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