Catalyst, process for its preparation and use
By preparing a catalyst with the chemical formula MxZn(2-x)[Co(CN)6]·yH2O·zL, the problems of complex catalyst preparation, high molecular weight, and numerous by-products in the existing technology were solved, and efficient and low-cost production of polyether carbonate and polycarbonate was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA PETROLEUM & CHEMICAL CORP
- Filing Date
- 2023-10-31
- Publication Date
- 2026-08-04
AI Technical Summary
Existing catalysts have complex preparation methods. When used to prepare polyether carbonate polyols and/or polycarbonates, they have high molecular weight, produce many byproducts, and have long reaction times, resulting in high costs.
A catalyst with a chemical formula of MxZn(2-x)[Co(CN)6]·yH2O·zL was prepared by reacting a mixed solution containing cyanate, zinc salt and organic ligands to produce a catalyst with a large specific surface area and excellent performance, which can be used for the copolymerization reaction of carbon dioxide and epoxide.
The catalyst preparation process has been simplified, the cost has been reduced, the catalytic efficiency has been improved, the product quality is well controlled, the reaction time has been shortened, and it is suitable for industrial production.
Smart Images
Figure CN119912501B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of catalyst preparation, specifically to a catalyst, its preparation method, and its application. Background Technology
[0002] Carbon dioxide and epoxides can be copolymerized to prepare polycarbonate or polyether carbonate polyols. Carbon dioxide is stable in this reaction and is difficult to react chemically, so research has mainly focused on catalyst development. Among them, the paper "Double metalcyanide catalyst prepared using H3Co(CN)6 for high carbonate fraction and molecular weight control in carbon dioxide / propylene oxide copolymerization" (J.Polym.Sci.,Part A:Polym.Chem,2013,51(22),4811) discloses the most widely used double metal cyanide coordination catalyst. This type of catalyst has high activity, is simple to prepare, and uses inexpensive raw materials, making it widely used in industrial production.
[0003] CN1044663A discloses a catalyst for synthesizing polycarbonate, polyester and polyether. It uses a high molecular weight organic complexing agent to prepare a highly active carbon dioxide / epoxide copolymerization catalyst. However, the polymerization generally requires 24-60 hours, which is a long reaction time and results in high polymerization costs when used in industrial production.
[0004] CN100484984C discloses a bimetallic catalyst and its preparation method and uses. The catalyst can significantly shorten the reaction time of copolymerizing epoxide and carbon dioxide to 2 hours. Using the catalyst can also significantly improve equipment utilization and reduce production costs. However, the catalyst preparation process is complex and the polyol product has a high molecular weight, between 4000 and 8000.
[0005] Therefore, there is an urgent need to develop a new catalyst. Summary of the Invention
[0006] The purpose of this invention is to overcome the problems of complex preparation methods of existing catalysts, high molecular weight and numerous by-products when used to prepare polyether carbonate polyols and / or polycarbonates, and to provide a catalyst, its preparation method and application.
[0007] To achieve the above objectives, a first aspect of the present invention provides a catalyst, wherein the chemical formula of the catalyst is as follows:
[0008] M x Zn (2-x)[Co(CN)6]X·yH2O·zL
[0009] Where M is a divalent metal ion, X is a monovalent anion, and L is an organic ligand; x, y, and z are all positive numbers, 0 <x<2;
[0010] The molar ratio of M, Zn, H2O to L is 1:(1-100):(1-40):(1-400).
[0011] A second aspect of the present invention provides a method for preparing a catalyst, wherein the method includes:
[0012] A catalyst is obtained by reacting a mixed solution containing cyanate solution, zinc salt, M salt and organic ligand.
[0013] A third aspect of the present invention provides the use of the above-described catalyst in the preparation of polyether carbonate polyols and / or polycarbonates.
[0014] Through the above technical solution, the catalyst, its preparation method, and its application provided by the present invention achieve the following beneficial effects:
[0015] (1) The catalyst provided by the present invention has the advantages of low cost, low dosage, high catalytic efficiency and good product quality control;
[0016] (2) The catalyst preparation method provided by the present invention simplifies the operating conditions and process flow, and the reaction conditions are mild, which is convenient for industrial production;
[0017] (3) When the catalyst provided by the present invention is used to prepare polyether carbonate polyol, its weight-average molecular weight is 2000 g / mol-4000 g / mol, the content of cyclic carbonate is 2-4 wt%, the conversion rate is 93-99%, and the amount of carbon dioxide fixed is 28-35 wt%; when used to prepare polycarbonate, its weight-average molecular weight is 50000 g / mol-76000 g / mol, the content of cyclic carbonate is 2-4 wt%, the conversion rate is 93-99%, and the amount of carbon dioxide fixed is 30-43 wt%. Attached Figure Description
[0018] Figure 1 This is a TEM image of the catalyst prepared in Example 1 of the present invention;
[0019] Figure 2 This is a TEM image of the catalyst prepared in Example 2 of the present invention;
[0020] Figure 3 This is the 1H NMR spectrum of the polyether carbonate polyol and the byproduct cyclic carbonate prepared in Test Example 1 of this invention. Detailed Implementation
[0021] The endpoints and any values of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of the various ranges, the endpoint values of the various ranges and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.
[0022] The first aspect of this invention provides a catalyst, wherein the chemical formula of the catalyst is as follows:
[0023] M x Zn (2-x) [Co(CN)6]X·yH2O·zL
[0024] Where M is a divalent metal ion, X is a monovalent anion, and L is an organic ligand; x, y, and z are all positive numbers, 0 <x<2;
[0025] The molar ratio of M, Zn, H2O to L is 1:(1-100):(1-40):(1-400).
[0026] In this invention, when the molar ratio of M, Zn, H2O and L meets the above-mentioned range, the catalyst has a large specific surface area and excellent catalyst performance.
[0027] According to the present invention, the catalyst has a specific surface area of 600-750 m². 2 / g.
[0028] In this invention, when the specific surface area of the catalyst meets the above-mentioned range, the catalyst has a large specific surface area and excellent catalyst performance.
[0029] According to the present invention, the divalent metal ion is selected from Ni. 2+ Cr 2+ Mg 2+ and Ca 2+ At least one of them.
[0030] In this invention, the divalent metal ions used are selected from Ni. 2+ Cr 2+ Mg 2+ and Ca 2+ The catalyst has a large specific surface area and excellent catalyst performance.
[0031] According to the present invention, the monovalent anion is selected from Cl. - ,Br - and I - At least one of them.
[0032] According to the present invention, the organic ligand is selected from at least one of tert-butanol (t-BuOH), ethylene glycol dimethyl ether (DMET), and polyether polyol (PP).
[0033] According to the present invention, the weight-average molecular weight of the polyether polyol is 1000 g / mol to 5000 g / mol.
[0034] A second aspect of the present invention provides a method for preparing a catalyst, wherein the method includes:
[0035] A catalyst is obtained by reacting a mixed solution containing cyanate solution, zinc salt, M salt and organic ligand.
[0036] According to the present invention, the cyanate is selected from at least one of K3Co(CN)6, Na3Co(CN)6 and Zn3[Co(CN)6]2.
[0037] According to the present invention, the zinc salt is selected from at least one of ZnCl2, ZnBr2 and ZnI2.
[0038] According to the present invention, the M salt is selected from at least one of NiCl2, CrCl2, MgCl2 and CaCl2.
[0039] According to the present invention, the mass-volume ratio of the cyanate, zinc salt, M salt and organic ligand is (1-5)g:(1-10)g:1g:(1-10)mL.
[0040] In this invention, when the molar ratio of the cyanate, zinc salt, M salt and organic ligand meets the above-mentioned range, the catalyst has a large specific surface area and excellent catalyst performance.
[0041] According to the present invention, the reaction conditions include a temperature of 10-50°C and a time of 0.5-24h.
[0042] According to the present invention, the reaction process further includes: repeatedly washing and centrifuging with a mixed solution of deionized water and organic ligands more than three times, followed by washing, centrifuging and drying with organic ligands a second time.
[0043] According to the present invention, the volume ratio of the single-use deionized water to the organic ligand is 1:(0.1-10).
[0044] According to the present invention, the drying conditions include: a vacuum degree of -0.095 MPa to -0.099 MPa and a temperature of 25-60°C.
[0045] A third aspect of the present invention provides the use of the above-described catalyst in the preparation of polyether carbonate polyols and / or polycarbonates.
[0046] In this invention, the method for preparing the polycarbonate includes: copolymerizing epoxide with CO2 in the presence of a catalyst to obtain polycarbonate, wherein the mass-to-volume ratio of the catalyst to the epoxide is 1 mg:(0.1-2) mL;
[0047] The method for preparing the polyether carbonate polyol includes: copolymerizing octanediol, epoxide and CO2 in the presence of a catalyst to obtain the polyether carbonate polyol, wherein the mass-volume ratio of the catalyst, octanediol and epoxide is 1 mg:(0.05-0.5) g:(0.1-2) mL.
[0048] The epoxide is selected from at least one of propylene oxide, ethylene oxide, cyclohexene oxide, butane oxide, isobutylene oxide, and cyclopentene oxide.
[0049] The conditions for the polymerization reaction include: a temperature of 60-150℃ and a time of 1-24h.
[0050] The absolute pressure of the carbon dioxide is 1-4 MPa.
[0051] The present invention will be described in detail below through embodiments. In the following embodiments,
[0052] All raw materials used in the examples and comparative examples are commercially available products.
[0053] Example 1
[0054] K3Co(CN)6 was added to 4 mL of deionized water, and then added dropwise to a mixed solution of ZnCl2, NiCl2, 5 mL of deionized water and tert-butanol. The mixture was reacted at 25 °C for 3 h. The first washing and first centrifugation were repeated more than 3 times with a mixed solution of water and tert-butanol at a volume ratio of 1:1. Then, the mixture was washed a second time with tert-butanol, centrifuged a second time, and dried at a vacuum of -0.097 MPa and a temperature of 45 °C to obtain catalyst A1, in which the mass-volume ratio of K3Co(CN)6, ZnCl2, NiCl2 and tert-butanol was 3 g: 5 g: 1 g: 5 mL.
[0055] Figure 1 This is a TEM image of the catalyst prepared in Example 1 of this invention. Figure 1 It can be seen that the catalyst mainly exhibits a columnar structure with a smooth surface.
[0056] Example 2
[0057] Add Na3Co(CN)6 to 4 mL of deionized water, then add dropwise a mixed solution of ZnBr2, CrCl2, 5 mL of deionized water and ethylene glycol dimethyl ether. React at 15 °C for 1 h. Repeat the first washing and first centrifugation more than 3 times with a mixed solution of water and ethylene glycol dimethyl ether at a volume ratio of 1:0.5. Then perform a second washing, a second centrifugation, and drying at a vacuum of -0.096 MPa and a temperature of 35 °C to obtain catalyst A2, in which the mass-volume ratio of Na3Co(CN)6, ZnBr2, CrCl2 and ethylene glycol dimethyl ether is 2 g:3 g:1 g:3 mL.
[0058] Figure 2 This is a TEM image of the catalyst prepared in Example 2 of this invention. Figure 2 It can be seen that the catalyst exhibits an overall coated structure with abundant microstructures.
[0059] Example 3
[0060] Zn3[Co(CN)6]2 was added to 4 mL of deionized water, and then added dropwise to a mixed solution of ZnI2, MgCl2, 5 mL of deionized water, and polyether polyol. The mixture was reacted at 40 °C for 6 h. The first washing and first centrifugation were repeated more than 3 times with a mixed solution of water and polyether polyol at a volume ratio of 1:3. Then, the mixture was washed a second time with polyether polyol, centrifuged a second time, and dried at -0.098 MPa and 50 °C to obtain catalyst A3. The mass-volume ratio of Zn3[Co(CN)6]2, ZnI2, MgCl2 to polyether polyol was 4 g:7 g:1 g:7 mL, and the weight-average molecular weight of polyether polyol was 5000 g / mol.
[0061] Example 4
[0062] Add K3Co(CN)6 to 4 mL of deionized water, then add dropwise a mixed solution of ZnCl2, CaCl2, 5 mL of deionized water and tert-butanol. React at 10 °C for 0.5 h. Repeat the first washing and first centrifugation more than 3 times with a mixed solution of water and tert-butanol with a volume ratio of 1:0.1. Then perform a second washing, a second centrifugation with tert-butanol and dry at a vacuum of -0.095 MPa and a temperature of 25 °C to obtain catalyst A4, wherein the mass-volume ratio of K3Co(CN)6, ZnCl2, CaCl2 and tert-butanol is 1 g:1 g:1 g:1 mL.
[0063] Example 5
[0064] K3Co(CN)6 was added to 4 mL of deionized water, and then added dropwise to a mixed solution of ZnCl2, NiCl2, 5 mL of deionized water, and polyether polyol. The mixture was reacted at 50 °C for 24 h. The first washing and first centrifugation were repeated more than 3 times with a mixed solution of water and polyether polyol at a volume ratio of 1:10. Then, the mixture was washed a second time with polyether polyol, centrifuged a second time, and dried at a vacuum of -0.099 MPa and a temperature of 60 °C to obtain catalyst A5. The mass-volume ratio of K3Co(CN)6, ZnCl2, NiCl2 and polyether polyol was 5 g:10 g:1 g:10 mL, and the weight-average molecular weight of the polyether polyol was 1000 g / mol.
[0065] Comparative Example 1
[0066] The method of Example 1 is followed, except that catalyst D1 is prepared by using different contents of K3Co(CN)6, ZnCl2, NiCl2 and tert-butanol, wherein the mass-volume ratio of K3Co(CN)6, ZnCl2, NiCl2 and tert-butanol is 0.5g:0.5g:1g:0.5mL.
[0067] Comparative Example 2
[0068] The method of Example 1 is followed, except that catalyst D2 is prepared by using different contents of K3Co(CN)6, ZnCl2, NiCl2 and tert-butanol, wherein the mass-volume ratio of K3Co(CN)6, ZnCl2, NiCl2 and tert-butanol is 6g:13g:1g:13mL.
[0069] Test Example 1
[0070] The specific surface area of the catalysts in the above examples and comparative examples was measured.
[0071] Specific surface area was measured using BET.
[0072] The results are detailed in Table 1.
[0073] Table 1. Specific surface area test results of the catalyst
[0074]
[0075]
[0076] Test Example 2
[0077] The catalysts prepared in the examples and comparative examples were used to prepare polyether carbonate polyols and polycarbonates.
[0078] Polyether carbonate polyols and polycarbonates were detected using 1H NMR spectroscopy and gel permeation chromatography.
[0079] The conversion rate was measured as the amount of epoxide consumed divided by the amount of epoxide added.
[0080] The carbon dioxide fixation capacity of polyether carbonate polyols is calculated using the following formula:
[0081] W c % = 44A 1.3 / (58A 1.15 +102A 1.3 )×%,
[0082] Where A 1.5 A 1.3 and A 1.15 Represent Figure 3 Peak areas at chemical shifts of 1.5, 1.3, and 1.15 ppm in the 1H NMR spectrum.
[0083] The content of the byproduct cyclic carbonates is calculated according to the following formula:
[0084] W PC % = 102A 1.5 / [102(A 1.3 +A 1.5 )+58A 1.15 ]×%
[0085] Where A 1.5 A 1.3 and A 1.15 Represent Figure 3 Peak areas at chemical shifts of 1.5, 1.3, and 1.15 ppm in the 1H NMR spectrum.
[0086] The results are detailed in Tables 2 and 3, respectively.
[0087] The preparation method of polycarbonate includes: in the presence of 9 mg catalyst, 35 mL of epoxide is copolymerized with CO2 at an absolute pressure of 4 MPa to obtain polycarbonate.
[0088] The preparation method of polyether carbonate polyol includes: in the presence of 2 mg catalyst, 7.2 g octanediol, 35 mL epoxide and CO2 with an absolute pressure of 2 MPa are copolymerized to obtain polyether carbonate polyol.
[0089] Table 2
[0090]
[0091] As shown in Table 2, the catalyst prepared in the embodiments of the present invention is used to prepare polyether carbonate polyols with a weight-average molecular weight of 2000 g / mol-4000 g / mol, a cyclic carbonate content of 2-4 wt%, a conversion rate of 93-99%, and a carbon dioxide fixation of 28-35 wt%, all of which are significantly superior to the catalyst prepared in the comparative example for the preparation of polyether carbonate polyols.
[0092] Table 3
[0093]
[0094] As shown in Table 3, the catalyst prepared in the embodiments of the present invention for the preparation of polycarbonate has a weight-average molecular weight of 50,000 g / mol-76,000 g / mol, a cyclic carbonate content of 2-4 wt%, a conversion rate of 93-99%, and a carbon dioxide fixation of 30-43 wt%, all of which are significantly superior to the catalyst prepared in the comparative example for the preparation of polycarbonate.
[0095] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.
Claims
1. A catalyst, characterized in that, The chemical formula of the catalyst is: NiZn[Co(CN)6]Cl·2H2O·4 t -BuOH, CrZn[Co(CN)6]Br·2H2O·4DMET, MgZn[Co(CN)6]I·2H2O·4PP, CaZn[Co(CN)6]Cl·2H2O·4 t At least one of -BuOH and NiZn[Co(CN)6]Cl·2H2O·4PP; In the CrZn[Co(CN)6]Br·2H2O·4DMET, DMET refers to ethylene glycol dimethyl ether; In the MgZn[Co(CN)6]I·2H2O·4PP, PP refers to polyether polyol, and the weight-average molecular weight of the polyether polyol is 5000 g / mol. In the NiZn[Co(CN)6]Cl·2H2O·4PP, PP refers to polyether polyol, and the weight-average molecular weight of the polyether polyol is 1000 g / mol. The catalyst has a specific surface area of 600-750 m². 2 / g.
2. A method for preparing the catalyst according to claim 1, wherein, The method includes: A catalyst is obtained by reacting a mixed solution containing cyanate, zinc salt, M salt and organic ligand; The cyanate is selected from at least one of K3Co(CN)6, Na3Co(CN)6 and Zn3[Co(CN)6]2; The M salt is selected from at least one of NiCl2, CrCl2, MgCl2 and CaCl2; The mass-to-volume ratio of the cyanate, zinc salt, M salt and organic ligand is (1-5) g:(1-10) g:1 g:(1-10) mL; The zinc salt is selected from at least one of ZnCl2, ZnBr2 and ZnI2; The organic ligand is selected from at least one of tert-butanol, ethylene glycol dimethyl ether, and polyether polyol; The polyether polyol has a weight-average molecular weight of 1000 g / mol or 5000 g / mol.
3. The preparation method according to claim 2, wherein, The reaction conditions include a temperature of 10-50℃ and a time of 0.5-24 h.
4. The preparation method according to claim 2, wherein, The reaction process also includes: repeating the first washing and first centrifugation more than 3 times with a mixed solution containing water and organic ligands, followed by a second washing, a second centrifugation and drying with organic ligands.
5. The preparation method according to claim 4, wherein, The volume ratio of water to organic ligands in the first wash and the first centrifugation is 1:(0.1-10).
6. The preparation method according to claim 4, wherein, The drying conditions include: a vacuum of -0.095 MPa to -0.099 MPa and a temperature of 25-60°C.
7. The use of the catalyst according to claim 1 and the catalyst prepared by any one of the preparation methods of 2-6 in the preparation of polyether carbonate polyols and / or polycarbonates.