Catalyst as well as preparation method and application thereof

Abstract

The invention relates to the field of catalyst preparation, and discloses a catalyst and a preparation method and application thereof. The chemical formula of the catalyst is as follows: MxZn (2-x) [Co (CN) 6] X.yH2O.zL, 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 lt; xlt; 2; wherein the molar ratio of M to Zn to H2O to L is 1: (1-100): (1-40): (1-400). The catalyst has the advantages of low cost, small dosage, high catalysis efficiency, good product quality control and the like; the preparation method simplifies operation conditions and process flow, has mild reaction conditions, and is convenient for industrial production; the method is used for preparing polyether carbonate polyols and / or polycarbonates.

Description

Technical Field

[0001] The present invention relates to the field of catalyst preparation, and in particular to a catalyst and a preparation method and application thereof. Background Art

[0002] Carbon dioxide and epoxide can be copolymerized to prepare polycarbonate or polyether carbonate polyol. In this reaction, carbon dioxide is stable and difficult to react chemically, so the research is mainly focused on the development of catalysts. Among them, "Double metalcyanide catalyst prepared using H3Co(CN)6for 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 that double metal cyanide coordination catalysts are the most widely used. This type of catalyst has high activity, simple preparation, and low raw material cost, and is widely used in industrial production.

[0003] CN1044663A discloses a catalyst for synthesizing polycarbonate, polyester and polyether, which uses a high molecular weight organic complexing agent to prepare a highly active carbon dioxide / epoxide copolymerization catalyst. However, the polymerization generally takes 24-60 hours, and the reaction time is relatively long. When used in industrial production, the polymerization cost is relatively high.

[0004] CN100484984C discloses a bimetallic catalyst and its preparation method and use. The catalyst can significantly shorten the reaction time of epoxide and carbon dioxide copolymerization to 2 hours. The use of the catalyst can also significantly improve equipment utilization and reduce production costs. However, the catalyst preparation process is complicated and the molecular weight of the polyol product is relatively high, between 4000 and 8000.

[0005] Therefore, there is an urgent need to develop a new catalyst. Summary of the invention

[0006] The purpose of the present invention is to overcome the problems of complicated preparation method of catalyst in the prior art, high molecular weight and many by-products when used for preparing polyether carbonate polyol and / or polycarbonate, and to provide a catalyst and its preparation method and application.

[0007] In order to achieve the above object, the 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] Wherein, the molar ratio of M, Zn, H2O and 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 comprises:

[0012] A mixed solution containing a cyanate solution, a zinc salt, an M salt and an organic ligand is reacted to obtain a catalyst.

[0013] The third aspect of the present invention provides use of the above catalyst in the preparation of polyether carbonate polyols and / or polycarbonates.

[0014] Through the above technical solution, a catalyst provided by the present invention and its preparation method and application can achieve the following beneficial effects:

[0015] (1) The catalyst provided by the present invention has the advantages of low cost, small dosage, high catalytic efficiency, and good product quality control;

[0016] (2) The preparation method of the catalyst 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 2000g / mol-4000g / mol, the content of cyclic carbonate is 2-4wt%, the conversion rate is 93-99%, and the fixed amount of carbon dioxide is 28-35wt%; when it is used to prepare polycarbonate, its weight average molecular weight is 50000g / mol-76000g / mol, the content of cyclic carbonate is 2-4wt%, the conversion rate is 93-99%, and the fixed amount of carbon dioxide is 30-43wt%. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a TEM image of the catalyst prepared in Example 1 of the present invention;

[0019] Figure 2 is a TEM image of the catalyst prepared in Example 2 of the present invention;

[0020] Figure 3 This is the H-NMR spectrum of the polyether carbonate polyol and the by-product cyclic carbonate obtained in Test Example 1 of the present invention. DETAILED DESCRIPTION

[0021] The endpoints and any values ​​of the ranges disclosed in this article 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 each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0022] The first aspect of the present 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] Wherein, the molar ratio of M, Zn, H2O and L is 1:(1-100):(1-40):(1-400).

[0026] In the present invention, when the molar ratio of M, Zn, H2O and L satisfies the above range, the specific surface area of ​​the catalyst is large and the catalyst performance is excellent.

[0027] According to the present invention, the specific surface area of ​​the catalyst is 600-750m 2 / g.

[0028] In the present invention, when the specific surface area of ​​the catalyst satisfies the above range, the specific surface area of ​​the catalyst is large and the catalyst performance is excellent.

[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 .

[0030] In the present invention, the divalent metal ion is 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 .

[0032] According to the present invention, the organic ligand is selected from at least one of tert-butyl alcohol (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-5000 g / mol.

[0034] A second aspect of the present invention provides a method for preparing a catalyst, wherein the method comprises:

[0035] A mixed solution containing a cyanate solution, a zinc salt, an M salt and an organic ligand is reacted to obtain a catalyst.

[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: 1 g: (1-10) mL.

[0040] In the present invention, when the molar ratio of the cyanate, zinc salt, M salt and organic ligand meets the above range, the specific surface area of ​​the catalyst is large and the catalyst performance is excellent.

[0041] According to the present invention, the reaction conditions include: temperature of 10-50° C. and time of 0.5-24 h.

[0042] According to the present invention, the reaction process further comprises: repeating the first washing and the first centrifugation with a mixed solution of deionized water and organic ligand for more than 3 times, followed by the second washing with organic ligand, the second centrifugation and drying.

[0043] According to the present invention, the volume ratio of the single deionized water to the organic ligand is 1:(0.1-10).

[0044] According to the present invention, the drying conditions include: vacuum degree of -0.095 MPa to -0.099 MPa, and temperature of 25-60°C.

[0045] The third aspect of the present invention provides use of the above catalyst in the preparation of polyether carbonate polyols and / or polycarbonates.

[0046] In the present invention, the preparation method of the polycarbonate comprises: copolymerizing epoxide with CO2 in the presence of a catalyst to obtain polycarbonate, wherein the mass volume ratio of the catalyst to the epoxide is 1 mg: (0.1-2) mL;

[0047] The preparation method of the polyether carbonate polyol comprises: 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, butylene oxide, isobutylene oxide and cyclopentene oxide.

[0049] The polymerization reaction conditions include: temperature of 60-150° C. and time of 1-24 h.

[0050] The absolute pressure of the carbon dioxide is 1-4 MPa.

[0051] The present invention will be described in detail below by way of examples. In the following examples,

[0052] The raw materials used in the examples and comparative examples are all commercially available.

[0053] Example 1

[0054] K3Co(CN)6 was added to 4 mL of deionized water, and then dropped into a mixed solution of ZnCl2, NiCl2, 5 mL of deionized water and tert-butanol, and reacted at 25°C for 3 h. The first washing and the first centrifugation were repeated more than 3 times with a single mixed solution of water and tert-butanol in a volume ratio of 1:1, followed by a second washing with tert-butanol, a second centrifugation and drying at a vacuum degree 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 is a TEM image of the catalyst prepared in Example 1 of the present invention. Figure 1 It can be seen that the catalyst mainly presents a columnar structure with a smooth surface.

[0056] Example 2

[0057] Na3Co(CN)6 was added to 4 mL of deionized water, and then dropped into a mixed solution of ZnBr2, CrCl2, 5 mL of deionized water and ethylene glycol dimethyl ether, reacted at 15°C for 1 h, and the first washing and the first centrifugation were repeated more than 3 times with a single mixed solution of water and ethylene glycol dimethyl ether in a volume ratio of 1:0.5, followed by a second washing with ethylene glycol dimethyl ether, a second centrifugation and drying at a vacuum degree of -0.096 MPa and a temperature of 35°C to obtain catalyst A2, wherein the mass volume ratio of Na3Co(CN)6, ZnBr2, CrCl2 and ethylene glycol dimethyl ether was 2g:3g:1g:3mL.

[0058] Figure 2 is a TEM image of the catalyst prepared in Example 2 of the present invention. Figure 2 It can be seen that the catalyst as a whole presents a coated structure with rich microstructure.

[0059] Example 3

[0060] Zn3[Co(CN)6]2 was added to 4 mL of deionized water, and then dropped into a mixed solution of ZnI2, MgCl2, 5 mL of deionized water and polyether polyol, and reacted at 40°C for 6 h. The first washing and the first centrifugation were repeated more than 3 times with a single mixed solution of water and polyether polyol in a volume ratio of 1:3, followed by a second washing with polyether polyol, a second centrifugation and drying at a vacuum degree of -0.098 MPa and a temperature of 50°C to obtain catalyst A3, wherein the mass volume ratio of Zn3[Co(CN)6]2, ZnI2, MgCl2 to polyether polyol was 4g:7g:1g:7mL, and the weight average molecular weight of the polyether polyol was 5000 g / mol.

[0061] Example 4

[0062] K3Co(CN)6 was added to 4 mL of deionized water, and then dropped into a mixed solution of ZnCl2, CaCl2, 5 mL of deionized water and tert-butanol, and reacted at 10°C for 0.5 h. The first washing and the first centrifugation were repeated more than 3 times with a single mixed solution of water and tert-butanol in a volume ratio of 1:0.1, followed by a second washing with tert-butanol, a second centrifugation and drying at a vacuum degree 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 was 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 dropped into a mixed solution of ZnCl2, NiCl2, 5 mL of deionized water and polyether polyol, and reacted at 50°C for 24 hours. The first washing and the first centrifugation were repeated more than three times with a single mixed solution of water and polyether polyol in a volume ratio of 1:10, followed by a second washing with polyether polyol, a second centrifugation and drying at a vacuum degree of -0.099 MPa and a temperature of 60°C to obtain catalyst A5, wherein the mass volume ratio of K3Co(CN)6, ZnCl2, NiCl2 and polyether polyol was 5g:10g:1g:10mL, and the weight average molecular weight of the polyether polyol was 1000g / mol.

[0065] Comparative Example 1

[0066] The method of Example 1 is followed, except that different contents of K3Co(CN)6, ZnCl2, NiCl2 and tert-butanol are used to prepare catalyst D1, 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 different contents of K3Co(CN)6, ZnCl2, NiCl2 and tert-butanol are used to prepare catalyst D2, 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] The specific surface area was measured using BET.

[0072] The results are shown in Table 1.

[0073] Table 1 Specific surface area test results of 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] The polyether carbonate polyols and polycarbonates were detected by hydrogen nuclear magnetic resonance spectroscopy and gel permeation chromatography.

[0079] The conversion was measured as epoxide consumed / epoxide added.

[0080] The fixed amount of carbon dioxide in polyether carbonate polyol is calculated according to the following formula:

[0081] W c %=44A 1.3 / (58A 1.15 +102A 1.3 )×%

[0082] Among them A 1.5 , A 1.3 and A 1.15 Respectively represent Figure 3 The peak areas at chemical shifts of 1.5, 1.3 and 1.15 ppm in the H NMR spectrum.

[0083] The content of the by-product cyclic carbonate is calculated according to the following formula:

[0084] W PC % = 102A 1.5 / [102(A 1.3 +A 1.5 )+58A 1.15 ]×%

[0085] Among them A 1.5 , A 1.3 and A 1.15 Respectively represent Figure 3 The peak areas at chemical shifts of 1.5, 1.3 and 1.15 ppm in the H NMR spectrum.

[0086] The results are shown in Tables 2 and 3 respectively.

[0087] The preparation method of polycarbonate comprises: in the presence of 9 mg of catalyst, 35 mL of epoxide is subjected to copolymerization reaction with CO2 introduced at an absolute pressure of 4 MPa to obtain polycarbonate.

[0088] The preparation method of the polyether carbonate polyol comprises: in the presence of 2 mg of a catalyst, copolymerizing 7.2 g of octanediol and 35 mL of epoxide with CO2 at an absolute pressure of 2 MPa to obtain the polyether carbonate polyol.

[0089] Table 2

[0090]

[0091] As can be seen from Table 2, the catalyst prepared in the embodiment of the present invention is used to prepare polyether carbonate polyols, with a weight average molecular weight of 2000g / mol-4000g / mol, a cyclic carbonate content of 2-4wt%, a conversion rate of 93-99%, and a fixed amount of carbon dioxide of 28-35wt%, which are significantly superior to the catalyst prepared in the comparative example for preparing polyether carbonate polyols.

[0092] Table 3

[0093]

[0094] As can be seen from Table 3, the catalyst prepared in the embodiment of the present invention is used to prepare polycarbonate, with a weight average molecular weight of 50000 g / mol-76000 g / mol, a cyclic carbonate content of 2-4wt%, a conversion rate of 93-99%, and a fixed amount of carbon dioxide of 30-43wt%, which are significantly superior to the catalyst prepared in the comparative example for preparing polycarbonate.

[0095] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A catalyst, characterized in that The chemical formula of the catalyst is as follows: M x Zn (2-x) [Co(CN)6]X·yH2O·zL 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; Wherein, the molar ratio of M, Zn, H2O and L is 1:(1-100):(1-40):(1-400).

2. The catalyst according to claim 1, wherein The specific surface area of ​​the catalyst is 600-750m 2 / g; Preferably, the divalent metal ion is selected from Ni 2+ Cr 2+ Mg 2+ and Ca 2+ At least one of; Preferably, the monovalent anion is selected from Cl - Br - and I - At least one of; Preferably, the organic ligand is selected from at least one of tert-butyl alcohol, ethylene glycol dimethyl ether and polyether polyol; More preferably, the weight average molecular weight of the polyether polyol is 1000 g / mol-5000 g / mol.

3. A method for preparing a catalyst, characterized in that: The method comprises: A mixed solution containing cyanate, zinc salt, M salt and organic ligand is reacted to obtain a catalyst.

4. The preparation method according to claim 3, wherein The cyanate is selected from at least one of K3Co(CN)6, Na3Co(CN)6 and Zn3[Co(CN)6]2; Preferably, the zinc salt is selected from at least one of ZnCl2, ZnBr2 and ZnI2; Preferably, the M salt is selected from at least one of NiCl2, CrCl2, MgCl2 and CaCl2; Preferably, the organic ligand is selected from at least one of tert-butyl alcohol, ethylene glycol dimethyl ether and polyether polyol; More preferably, the weight average molecular weight of the polyether polyol is 1000 g / mol-5000 g / mol.

5. The preparation method according to claim 3 or 4, wherein The mass volume ratio of the cyanate, zinc salt, M salt and organic ligand is (1-5) g: (1-10) g: 1 g: (1-10) mL.

6. The preparation method according to any one of claims 3 to 5, wherein: The reaction conditions include: temperature of 10-50° C. and time of 0.5-24 h.

7. The preparation method according to any one of claims 3 to 6, wherein: The reaction process further comprises: repeating the first washing and the first centrifugation with a mixed solution containing water and organic ligand for more than 3 times, and then performing the second washing with an organic ligand, the second centrifugation and drying.

8. The preparation method according to claim 7, wherein: The volume ratio of water to organic ligand in the first washing and the first centrifugation is 1:(0.1-10).

9. The preparation method according to any one of claims 7 or 8, wherein: The drying conditions include: vacuum degree of -0.095 MPa to -0.099 MPa, and temperature of 25-60°C.

10. Use of the catalyst according to claim 1 or 2 and the catalyst prepared by the preparation method according to any one of claims 3 to 9 in the preparation of polyether carbonate polyol and / or polycarbonate.

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