Preparation method of Zn-Co bimetallic catalyst and method for catalytically preparing allyl alcohol polyether

Abstract

The invention discloses a preparation method of a Zn-Co bimetallic catalyst and a method for catalytically preparing allyl alcohol polyether, and the method specifically comprises the following steps: (1) adding cobalt potassium cyanide into deionized water, and ultrasonically dispersing uniformly to obtain a solution A; adding zinc chloride and a complexing agent into deionized water, and ultrasonically dispersing uniformly to obtain a solution B; (2) adding the solution A into the solution B, reacting, then adding a mixture of a complexing agent and a triblock polymer, ultrasonically dispersing uniformly, continuously reacting, and centrifuging to obtain a precipitate; and (3) repeatedly cleaning and centrifuging the precipitate, and carrying out vacuum drying to obtain the product. A series of middle-high molecular weight allyl alcohol polyether products with narrow molecular weight distribution can be obtained, and the method is suitable for being applied to the downstream industries such as the fields of flatting agents, defoaming agents, textile auxiliaries, leather anti-sticking and water reducing agents and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of bimetallic catalysts, and more particularly to a Zn-Co bimetallic catalyst and a preparation method and application thereof. Background Art

[0002] Allyl alcohol polyether is a very important chemical raw material. According to its molecular weight, it is divided into low molecular weight (200-600), medium molecular weight (600-1000), medium-high molecular weight (1000-2000) and high molecular weight (2000-5000). It is widely used in coatings, adhesives, water reducers, sealants, textiles and personal care products.

[0003] Currently, there are two main methods for the synthesis of allyl alcohol polyethers: base catalysis and double metal cyanide catalysis. During base-catalyzed ring-opening polymerization of propylene oxide, rearrangement reactions are prone to occur. Propylene oxide monomers rearrange to allyl alcohol, which can act as a new initiator for the polymerization reaction. This rearrangement generates unsaturated groups in the polymer and increases the number of polymer chains, making it difficult to produce high-molecular-weight polyethers. This limits the molecular weight and molecular weight distribution of the polyethers, making the preparation of high-molecular-weight polyethers difficult. Furthermore, post-polymerization requires post-treatment steps to neutralize the base catalyst and separate the inorganic salt from the polymer.

[0004] Compared with base catalysis, double metal cyanide catalysis has become one of the main catalysts for the ring-opening polymerization of epoxides, especially propylene oxide. So far, the frontier research mainly focuses on complexing agents, among which the representative reports mainly include: (1) Using linear dicarbonyl compounds (3,4-hexanedione (34-HD), β-dicarbonyl compounds such as acetylacetone (AA), methyl acetoacetate (MAA), ethyl acetoacetate (EAA) and tert-butyl acetoacetate (TBAA), γ-dicarbonyl compound 2,5-hexanedione (25-HD)) as complexing agents and polypropylene glycol (PPG-400) as initiator, a series of high molecular weight polyethers were synthesized (Tran CH, Pham LTT, Lee Y, et al. Mechanistic insights on Zn(II)-Co(III) double metal cyanide-catalyzed ring-opening polymerization of epoxides[J]. Journal of Catalysis, 2019, 372: 86-102; Tran CH, Pham LTT, Jang HB, et al. Effect of α-, β-, γ-, and δ-dicarbonyl complexing agents on the double metalcyanide-catalyzed ring-opening polymerization of propylene oxide[J].CatalToday,2021,375:429-440.); (2) Using linear nitrile compounds (acetonitrile (AN), isobutyl cyanide (IBN), n-butyl cyanide (BN), succinonitrile (SN), propionitrile (PN), 2-methylbutyronitrile (MBN) and trimethylnitrile (TMA)) as complexing agents, a series of double metal cyanide catalysts were prepared, and polypropylene glycol (PPG-400) was used as an initiator for the synthesis of polyether, polyester and polycarbonate polyols (Tran CH,Lee SJ,Moon B,et al.Organonitriles as complexing agents for thedouble metal cyanide-catalyzed synthesis of polyether,polyester,andpolycarbonate polyols[J].Catalysis Today, 2023, 418: 114125.); (3) Using Schiff base as a complexing agent and PEG-600 as an initiator, the polyether polyol was synthesized by ring-opening polymerization with propylene oxide.

[0005] A review of existing bimetallic catalysts and polyether synthesis methods reveals that the complexing agents used in catalyst preparation are primarily linear, such as the classic tert-butyl alcohol, which can be used to modulate catalyst activity. However, research on cyclic complexing agents has yet to be reported, and the synthesis of allyl alcohol polyethers using bimetallic catalysts has yet to be reported. It is well known that complexing agents of varying types, structures, and functions can have varying degrees of impact on bimetallic catalysts, such as catalytic activity, selectivity, and stability.

[0006] Therefore, how to develop a bimetallic catalyst prepared based on a cyclic complexing agent is an urgent problem that needs to be solved by those skilled in the art. Summary of the Invention

[0007] In view of this, the object of the present invention is to provide a Zn-Co bimetallic catalyst and a preparation method and application thereof to address the deficiencies in the prior art.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] A method for preparing a Zn-Co bimetallic catalyst specifically comprises the following steps:

[0010] (1) Potassium cobalt cyanide (K3Co(CN)6) was added to deionized water and uniformly dispersed by ultrasonication to obtain solution A; zinc chloride (ZnCl2) and a complexing agent were added to deionized water and uniformly dispersed by ultrasonication to obtain solution B;

[0011] (2) adding solution A to solution B, reacting, then adding a mixture of a complexing agent and a triblock polymer, ultrasonically dispersing the mixture uniformly, continuing the reaction, and centrifuging to obtain a precipitate;

[0012] (3) The precipitate is repeatedly washed and centrifuged, and vacuum dried to obtain a Zn-Co bimetallic catalyst (DMC).

[0013] As a further improvement, in the above step (1), the complexing agent is at least one of saccharin (SAN), phthalic anhydride (PA), phthalimide (PI), N-hydroxyphthalimide (N-HPI) and N-bromophthalimide (N-BrPI), preferably at least one of saccharin and phthalic anhydride.

[0014] The structural formula is as follows:

[0015]

[0016] As a further improvement, in the above step (1), the molar ratio of potassium cobalt cyanide to zinc chloride is 1:(6-10), preferably 1:6; and the molar ratio of the complexing agent to zinc chloride is 1:(8.7-10.1).

[0017] Furthermore, in the above step (2), the triblock polymer is poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123).

[0018] As a further improvement, in the above step (2), the addition conditions are 70°C, vigorous stirring, and slow dropwise addition; the reaction time is 30 minutes; the molar ratio of the complexing agent to the triblock polymer is 1:(13-16), preferably 1:14.8; the reaction is continued at 70°C, vigorous stirring, and for 10 minutes; the centrifugal speed is 8000 rpm, and the time is 3 minutes.

[0019] As a further improvement, in the above step (3), the reagents used for repeated cleaning and centrifugation are deionized water and anhydrous ethanol, respectively, for three times; the vacuum drying temperature is 80° C. and the time is 24 h.

[0020] A further beneficial effect of the above method is that unreacted zinc chloride is thoroughly cleaned by repeated washing and centrifugation.

[0021] A method for catalytically preparing allyl alcohol polyether comprises the following steps:

[0022] Allyl alcohol (initiator), propylene oxide (PO) and the Zn-Co bimetallic catalyst prepared by the above preparation method are placed in a reaction kettle in sequence;

[0023] The mixture was purged with N2, polymerized, dissolved and centrifuged repeatedly, and dried under vacuum until the weight was constant, thereby obtaining allyl alcohol polyether with medium to high molecular weight (659-1618 g / mol) and narrow molecular weight distribution.

[0024] The reaction equation is as follows:

[0025]

[0026] As a further improvement, the molar ratio of allyl alcohol to propylene oxide is 1:(11-55), preferably 1:33;

[0027] The addition amount of the Zn-Co bimetallic catalyst is 5%-34% of the sum of the mass of allyl alcohol and propylene oxide, preferably 10%;

[0028] The flow rate of N2 purge was 20 mL / min and the time was 5 min;

[0029] The polymerization temperature is 90-120° C., preferably 105° C., and the pressure is 1-10 bar, preferably 5 bar. When the pressure rises to 14 bar, the reaction is carried out for 20 hours, cooled to room temperature, and the pressure is slowly released.

[0030] A further beneficial effect of the above method is that dissolved gases in the reaction mixture are removed by N2 purging, creating an inert atmosphere in the reactor.

[0031] In the present invention, an allyl alcohol polyether with high molecular weight and narrow molecular weight distribution is prepared in the catalytic preparation by using the prepared Zn-Co bimetallic catalyst.

[0032] It can be seen from the above technical solution that compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] The present invention adopts saccharin and other substances as novel cyclic complexing agents, thereby changing the crystallinity of the catalyst, the electronic environment of the Zn atom in the catalyst, and the coordination mode with the complex to varying degrees, thereby preparing a series of novel and highly efficient Zn-Co bimetallic catalysts. When used in the ring-opening polymerization reaction of allyl alcohol and propylene oxide, a series of medium- and high-molecular-weight allyl alcohol polyether products with narrow molecular weight distribution can be obtained compared with traditional alcohol linear complexing agents such as tert-butyl alcohol (TBA). The allyl alcohol polyether products are suitable for application in downstream industries such as leveling agents, defoaming agents, textile auxiliaries, leather anti-sticking and water-reducing agents, and other fields. DETAILED DESCRIPTION

[0034] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0035] In the following examples,

[0036] Zinc chloride was purchased from Shanghai Anaiji Chemical Co., Ltd.

[0037] Potassium cobalt cyanide was purchased from Shanghai Anaiji Chemical Co., Ltd.

[0038] Saccharin was purchased from Shanghai Anaiji Chemical Co., Ltd.

[0039] N-hydroxyphthalimide was purchased from Shanghai Anaiji Chemical Co., Ltd.

[0040] Tert-Butanol, Liaoning Quanrui Reagent Co., Ltd.;

[0041] Phthalic anhydride was purchased from Shanghai Anaiji Chemical Co., Ltd.

[0042] Propylene oxide was purchased from Shanghai Anaiji Chemical Co., Ltd.

[0043] Allyl alcohol was purchased from Jilin Ruiji Special Chemicals Co., Ltd.;

[0044] Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) was purchased from Shanghai Anaiji Chemical Co., Ltd.

[0045] Example 1

[0046] The preparation method of the Zn-Co bimetallic catalyst specifically comprises the following steps:

[0047] (1) Add 1.196 g (0.036 mol) of potassium cobalt cyanide to 6 mL of deionized water and disperse uniformly with ultrasonic waves to obtain solution A; add 14.12 g (0.216 mol) of zinc chloride and 3.705 g (0.025 mol) of phthalic anhydride to 18 mL of deionized water and disperse uniformly with ultrasonic waves to obtain solution B;

[0048] (2) Solution A was slowly added dropwise to solution B at 70°C with vigorous stirring, and the mixture was allowed to react for 30 min. Then, a mixture of 3.705 g (0.025 mol) of phthalic anhydride and 2.15 g (0.37 mmol) of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) was added and uniformly dispersed by ultrasonication. The mixture was allowed to react for 10 min at 70°C with vigorous stirring, and the mixture was centrifuged at 8000 rpm for 3 min to obtain a precipitate.

[0049] (3) The precipitate was washed repeatedly with deionized water and centrifuged three times, then washed repeatedly with anhydrous ethanol and centrifuged three times, and dried under vacuum at 80°C for 24 h to obtain the Zn-Co bimetallic catalyst (DMC-PA);

[0050] The preparation method of allyl alcohol polyether specifically comprises the following steps:

[0051] (1) 0.2909 g of allyl alcohol, 9.6 g of propylene oxide, and 0.03 g of Zn-Co bimetallic catalyst (DMC-PA) were placed in sequence into a 50 mL polytetrafluoroethylene-lined autoclave equipped with a magnetic stirrer. The autoclave was purged with nitrogen at a flow rate of 20 mL / min for 5 min and pressurized to 5 bar.

[0052] (2) heating the mixture at 105° C. and stirring vigorously at 500 rpm. When the reaction reaches the desired temperature, the pressure is increased to 14 bar and the reaction is continued for 20 hours. After the reactor is cooled to room temperature, the pressure is slowly released to obtain a crude allyl alcohol polyether;

[0053] (3) The crude allyl alcohol polyether was dissolved in anhydrous ethanol and centrifuged three times, and then vacuum-dried at 80° C. to a constant weight to obtain pure allyl alcohol polyether.

[0054] Example 2

[0055] The preparation method of the Zn-Co bimetallic catalyst specifically comprises the following steps:

[0056] (1) Add 1.196 g (0.036 mol) of potassium cobalt cyanide to 6 mL of deionized water and disperse uniformly with ultrasonic waves to obtain solution A; add 14.12 g (0.216 mol) of zinc chloride and 4.580 g (0.025 mol) of saccharin to 18 mL of deionized water and disperse uniformly with ultrasonic waves to obtain solution B;

[0057] (2) Solution A was slowly added dropwise to solution B at 70°C with vigorous stirring, and the mixture was allowed to react for 30 min. Then, a mixture of 4.580 g (0.025 mol) of saccharin and 2.15 g (0.37 mmol) of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) was added and uniformly dispersed by ultrasonication. The mixture was allowed to react for 10 min at 70°C with vigorous stirring, and the mixture was centrifuged at 8000 rpm for 3 min to obtain a precipitate.

[0058] (3) The precipitate was washed repeatedly with deionized water and centrifuged three times, then washed repeatedly with anhydrous ethanol and centrifuged three times, and dried under vacuum at 80°C for 24 h to obtain the Zn-Co bimetallic catalyst (DMC-SAN);

[0059] The preparation method of allyl alcohol polyether specifically comprises the following steps:

[0060] (1) 0.2909 g of allyl alcohol, 9.6 g of propylene oxide, and 0.03 g of Zn-Co bimetallic catalyst (DMC-SAN) were placed in sequence into a 50 mL polytetrafluoroethylene-lined autoclave equipped with a magnetic stirrer. The autoclave was purged with nitrogen at a flow rate of 20 mL / min for 5 min and pressurized to 5 bar.

[0061] (2) heating the mixture at 105° C. and stirring vigorously at 500 rpm. When the reaction reaches the desired temperature, the pressure is increased to 14 bar and the reaction is continued for 20 hours. After the reactor is cooled to room temperature, the pressure is slowly released to obtain a crude allyl alcohol polyether;

[0062] (3) The crude allyl alcohol polyether was dissolved in anhydrous ethanol and centrifuged three times, and then vacuum-dried at 80° C. to a constant weight to obtain pure allyl alcohol polyether.

[0063] Example 3

[0064] The preparation method of the Zn-Co bimetallic catalyst specifically comprises the following steps:

[0065] (1) Add 1.196 g (0.036 mol) of potassium cobalt cyanide to 6 mL of deionized water and disperse uniformly with ultrasonic waves to obtain solution A; add 14.12 g (0.216 mol) of zinc chloride and 5.405 g (0.025 mol) of N-hydroxyphthalimide to 18 mL of deionized water and disperse uniformly with ultrasonic waves to obtain solution B;

[0066] (2) Solution A was slowly added dropwise to solution B at 70°C with vigorous stirring, and the mixture was allowed to react for 30 min. Then, a mixture of 5.405 g (0.025 mol) of N-hydroxyphthalimide and 2.15 g (0.37 mmol) of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) was added and uniformly dispersed by ultrasonication. The mixture was allowed to react for 10 min at 70°C with vigorous stirring, and the mixture was centrifuged at 8000 rpm for 3 min to obtain a precipitate.

[0067] (3) The precipitate was washed repeatedly with deionized water and centrifuged three times, then washed repeatedly with anhydrous ethanol and centrifuged three times, and dried under vacuum at 80°C for 24 h to obtain the Zn-Co bimetallic catalyst (DMC-N-HPI);

[0068] The preparation method of allyl alcohol polyether specifically comprises the following steps:

[0069] (1) 0.2909 g of allyl alcohol, 9.6 g of propylene oxide, and 0.03 g of Zn-Co bimetallic catalyst (DMC-N-HPI) were placed in a 50 mL polytetrafluoroethylene-lined autoclave equipped with a magnetic stirrer, and the autoclave was purged with N2 at a flow rate of 20 mL / min for 5 min and pressurized to 5 bar.

[0070] (2) heating the mixture at 105° C. and stirring vigorously at 500 rpm. When the reaction reaches the desired temperature, the pressure is increased to 14 bar and the reaction is continued for 20 hours. After the reactor is cooled to room temperature, the pressure is slowly released to obtain a crude allyl alcohol polyether;

[0071] (3) The crude allyl alcohol polyether was dissolved in anhydrous ethanol and centrifuged three times, and then vacuum-dried at 80° C. to a constant weight to obtain pure allyl alcohol polyether.

[0072] Comparative Example 1

[0073] The preparation method of the Zn-Co bimetallic catalyst specifically comprises the following steps:

[0074] (1) Add 1.196 g (0.036 mol) of potassium cobalt cyanide to 6 mL of deionized water and disperse uniformly with ultrasonic waves to obtain solution A; add 14.12 g (0.216 mol) of zinc chloride and 6.13 mL of tert-butyl alcohol to 18 mL of deionized water and disperse uniformly with ultrasonic waves to obtain solution B;

[0075] (2) Solution A was slowly added dropwise to solution B at 70°C with vigorous stirring, and the reaction was continued for 30 min. Then, a mixture of 6.13 mL of tert-butyl alcohol and 2.15 g (0.37 mmol) of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) was added and uniformly dispersed by ultrasonication. The reaction was continued at 70°C with vigorous stirring for 10 min, and the mixture was centrifuged at 8000 rpm for 3 min to obtain a precipitate.

[0076] (3) The precipitate was washed repeatedly with deionized water and centrifuged three times, then washed repeatedly with anhydrous ethanol and centrifuged three times, and dried under vacuum at 80°C for 24 h to obtain the Zn-Co bimetallic catalyst (DMC-TBA);

[0077] The preparation method of allyl alcohol polyether specifically comprises the following steps:

[0078] (1) 0.2909 g of allyl alcohol, 9.6 g of propylene oxide, and 0.03 g of Zn-Co bimetallic catalyst (DMC-TBA) were placed in a 50 mL polytetrafluoroethylene-lined autoclave equipped with a magnetic stirrer, and the autoclave was purged with nitrogen at a flow rate of 20 mL / min for 5 min and pressurized to 5 bar.

[0079] (2) heating the mixture at 105° C. and stirring vigorously at 500 rpm. When the reaction reaches the desired temperature, the pressure is increased to 14 bar and the reaction is continued for 20 hours. After the reactor is cooled to room temperature, the pressure is slowly released to obtain a crude allyl alcohol polyether;

[0080] (3) The crude allyl alcohol polyether was dissolved in anhydrous ethanol and centrifuged three times, and then vacuum-dried at 80° C. to a constant weight to obtain pure allyl alcohol polyether.

[0081] Comparative Example 2

[0082] The preparation method of the Zn-Co bimetallic catalyst specifically comprises the following steps:

[0083] (1) Add 1.196 g (0.036 mol) of potassium cobalt cyanide to 6 mL of deionized water and disperse uniformly by ultrasonication to obtain solution A; add 14.12 g (0.216 mol) of zinc chloride to 18 mL of deionized water and disperse uniformly by ultrasonication to obtain solution B;

[0084] (2) Solution A was slowly added dropwise to solution B at 70°C with vigorous stirring, and the mixture was allowed to react for 30 min. Then, 2.15 g (0.37 mmol) of a mixture of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) was added and uniformly dispersed by ultrasonication. The mixture was allowed to react for 10 min at 70°C with vigorous stirring, and the mixture was centrifuged at 8000 rpm for 3 min to obtain a precipitate.

[0085] (3) The precipitate was washed repeatedly with deionized water and centrifuged three times, then washed repeatedly with anhydrous ethanol and centrifuged three times, and dried under vacuum at 80°C for 24 h to obtain the Zn-Co bimetallic catalyst (DMC-pure);

[0086] The preparation method of allyl alcohol polyether specifically comprises the following steps:

[0087] (1) 0.2909 g of allyl alcohol, 9.6 g of propylene oxide, and 0.03 g of Zn-Co bimetallic catalyst (DMC-pure) were placed in sequence into a 50 mL polytetrafluoroethylene-lined autoclave equipped with a magnetic stirrer. The autoclave was purged with nitrogen at a flow rate of 20 mL / min for 5 min and pressurized to 5 bar.

[0088] (2) heating the mixture at 105° C. and stirring vigorously at 500 rpm. When the reaction reaches the desired temperature, the pressure is increased to 14 bar and the reaction is continued for 20 hours. After the reactor is cooled to room temperature, the pressure is slowly released to obtain a crude allyl alcohol polyether;

[0089] (3) The crude allyl alcohol polyether was dissolved in anhydrous ethanol and centrifuged three times, and then vacuum-dried at 80° C. to a constant weight to obtain pure allyl alcohol polyether.

[0090] Performance Testing

[0091] The number average molecular weight (Mn) and weight average molecular weight (Mw) of each of the pure allyl alcohol polyethers prepared in Examples 1-3 and Comparative Examples 1-2 were determined by gel permeation chromatography (GPC). The analysis was performed using a Shimadzu LC-20A instrument. The samples were dissolved in tetrahydrofuran and measured at a flow rate of 1 mL / min using a polystyrene sample as a standard at 25°C.

[0092] The results are shown in Table 1.

[0093] Table 1 Mn and Mw of pure allyl alcohol polyethers of Examples 1-3 and Comparative Examples 1-2

[0094]

[0095] Examples 1 to 3 respectively used different complexing agents, phthalic anhydride, saccharin, and N-hydroxyphthalimide. From the test results, it can be seen that the complexing agent phthalic anhydride in Example 1 has the best effect, achieving the regulation of the molecular weight of the allyl alcohol polyether from low molecular weight to medium and high molecular weight. For medium and high molecular weight allyl alcohol polyethers, the allyl alcohol polyether obtained by the cyclic complexing agent has a narrower molecular weight distribution.

[0096] As shown in Table 1, the catalyst prepared in Comparative Example 2 without the addition of a complexing agent does not have the effect of catalyzing the synthesis of allyl alcohol polyethers. Under the same conditions, compared to the commercially available classic linear complexing agent TBA in Comparative Example 1, the Zn-Co bimetallic catalysts synthesized in Examples 1-3, due to the introduction of cyclic complexing agents (PA, SAN, N-HPI), change the crystallinity of the Zn-Co bimetallic catalyst, the electronic environment of the Zn atom, and the coordination mode with the complex during the preparation of allyl alcohol polyethers, thereby achieving regulation of the molecular weight of the allyl alcohol polyethers from low molecular weight to medium and high molecular weight. For medium and high molecular weight allyl alcohol polyethers, the allyl alcohol polyethers obtained with the cyclic complexing agent have a narrower molecular weight distribution.

[0097] From the Mn and Mw test results of the pure allyl alcohol polyethers of Examples 1-3 and Comparative Examples 1-2 in Table 1, it can be seen that the catalytic ability and activity of the Zn-Co bimetallic catalysts synthesized in Examples 1-3 of the present invention are significantly higher than those of the commercially available classic Zn-Co bimetallic catalyst in Comparative Example 1.

[0098] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a Zn-Co bimetallic catalyst, characterized in that: The specific steps include: (1) adding potassium cobalt cyanide to deionized water and uniformly dispersing by ultrasonication to obtain solution A; adding zinc chloride and a complexing agent to deionized water and uniformly dispersing by ultrasonication to obtain solution B; (2) adding solution A to solution B, reacting, then adding a mixture of a complexing agent and a triblock polymer, ultrasonically dispersing the mixture uniformly, continuing the reaction, and centrifuging to obtain a precipitate; (3) The precipitate is repeatedly washed and centrifuged, and vacuum dried to obtain the Zn-Co bimetallic catalyst.

2. The method for preparing a Zn-Co bimetallic catalyst according to claim 1, characterized in that: In step (1), the complexing agent is any one of saccharin, phthalic anhydride, phthalimide, N-hydroxyphthalimide and N-bromophthalimide.

3. The method for preparing a Zn-Co bimetallic catalyst according to claim 1, wherein: In step (1), the molar ratio of the potassium cobalt cyanide to zinc chloride is 1:(6-10); and the molar ratio of the complexing agent to zinc chloride is 1:(8.7-10.1).

4. The method for preparing a Zn-Co bimetallic catalyst according to claim 1, wherein: In step (2), the triblock polymer is poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol).

5. The method for preparing a Zn-Co bimetallic catalyst according to claim 1, characterized in that: The specific steps of step (2) are as follows: The addition conditions are 70°C, vigorous stirring, and slow dropwise addition; The reaction time is 30 min; The molar ratio of the complexing agent to the triblock polymer is 1:(13-16); The conditions for the continued reaction are 70°C, vigorous stirring, and time for 10 minutes; The centrifugal speed is 8000 rpm and the time is 3 minutes.

6. The method for preparing a Zn-Co bimetallic catalyst according to claim 1, characterized in that: In step (3), The reagents for repeated washing and centrifugation are deionized water and anhydrous ethanol, and the number of times is 3; The vacuum drying temperature is 80° C. and the time is 24 h.

7. A method for catalytically preparing allyl alcohol polyether, characterized in that: The following steps are included Allyl alcohol, propylene oxide and the Zn-Co bimetallic catalyst prepared by the preparation method according to any one of claims 1 to 6 are sequentially placed in a reaction kettle; N2 purging, polymerization reaction, repeated dissolution and centrifugation, vacuum drying to a constant weight, to obtain the allyl alcohol polyether; The reaction equation is as follows: The reaction equation is as follows:

8. The method for preparing allyl alcohol polyether by catalysis according to claim 7, characterized in that: The specific steps are as follows: The molar ratio of allyl alcohol to propylene oxide is 1:(11-55); The amount of the Zn-Co bimetallic catalyst added is 5%-34% of the sum of the mass of allyl alcohol and propylene oxide; The flow rate of the N2 purge was 20 mL / min and the time was 5 min; The polymerization reaction temperature is 90-120° C. and the pressure is 1-10 bar. When the pressure is increased to 14 bar, the reaction is carried out for 20 hours, cooled to room temperature, and the pressure is slowly released.

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