Linkage device suitable for transesterification reaction control and solid catalyst filtering, recycling and reusing

Abstract

The utility model relates to the technical field of chemical equipment, and particularly discloses a linkage device suitable for ester exchange reaction control and solid catalyst filtering, recycling and reusing, which comprises a kettle type reactor 1 with a stirring function, a rectification separation tower 2, a tower top primary condenser 3, a tower top secondary condenser 4, a reflux tank 5, a reflux pump 6, a collecting tank 7, a filtering device 8 and a receiving tank 9. The content of each component in the reaction device is adjusted through interlocking control of the reflux tank 5, the reflux pump 6 and the collection tank 7, so that forward proceeding of the reaction is promoted, and the raw materials are further converted completely. In the reaction process, the catalyst can be concentrated and directly recycled through the filtering device 8, the catalyst does not need to be filtered out, and continuous esterification reaction can be achieved. Finally, the synthetic liquid and the solid catalyst can be thoroughly separated, and the catalyst can be updated or replaced.

Description

Technical Field

[0001] The utility model relates to a linkage device suitable for controlling ester exchange reactions and filtering and recovering solid catalysts, and belongs to the technical field of chemical reactions and filtering equipment. Background Art

[0002] In existing fine chemical reaction devices, the synthesis reaction usually uses a tank reactor to carry out the reaction at a certain temperature or pressure to obtain a synthetic product, and then the main synthetic product is refined or distilled to obtain the final product. The same is true for the ester exchange reaction.

[0003] The esterification reaction is a reversible reaction. In the ester solution, there are small amounts of free alcohol and acid. The transesterification reaction is carried out based on the reversibility of the esterification reaction.

[0004] Since the transesterification reaction is generally mild and an endothermic reaction, the reaction speed is slow, resulting in a longer time for the transesterification reaction using a kettle structure, resulting in low reaction efficiency and high energy consumption cost.

[0005] Due to the reversibility of the transesterification reaction, if the transesterification reaction is to proceed, at least one of the following two conditions must be met: 1. The stability of the new ester generated is stronger than the previous ester; 2. The new alcohol generated can be continuously evaporated during the reaction.

[0006] Based on the principle of ester exchange reaction, the utility model provides a linkage device suitable for ester exchange reaction control and solid catalyst filtering and recovery application to solve the problems raised in the above-mentioned background technology. At the same time, after the synthesis reaction is completed, the solid catalyst in the synthesis liquid needs to be filtered and separated, and the catalyst can be applied to the next synthesis reaction. Utility Model Content

[0007] The problem to be solved by the utility model is that, due to the reversibility of the ester exchange reaction, in a conventional kettle reactor, when new esters and alcohols are generated, they coexist in the reactor and reach a certain concentration, and at the same time, there is a reverse reaction, so that the content of the target product cannot be increased, affecting the reaction to proceed to the forward reaction, and the raw alcohol cannot be deeply converted.

[0008] At the same time, after the reaction is completed, the solid catalyst needs to be recovered and reused to separate the solid and liquid and improve the separation effect.

[0009] Therefore, an esterification reaction device is needed to make the raw materials basically completely converted and the reaction proceeds in the forward direction.

[0010] The purpose of the utility model is to overcome the defects in the prior art and provide a linkage device suitable for controlling transesterification reaction and filtering and recovering solid catalysts.

[0011] In order to achieve the above technical effects, the technical solution of the utility model is: a linkage device suitable for controlling transesterification reaction and filtering and recovering solid catalyst, comprising a stirred kettle reactor (1), a distillation separation tower (2), a first-level condenser at the top of the tower (3), a second-level condenser at the top of the tower (4), a reflux tank (5), a reflux pump (6), a collection tank (7), a filtering device (8) and a receiving tank (9), wherein the content of each component in the reaction process is adjusted by interlocking control of the reflux tank (5), the reflux pump (6) and the collection tank (7), so as to promote the forward progress of the reaction. After the reaction is completed, the synthetic liquid and the solid catalyst are separated by the filtering device (8), and the solid catalyst is used for the next batch of synthesis.

[0012] Furthermore, the reflux tank (5) is provided with a liquid level meter (51).

[0013] Furthermore, the reflux pump (6) is interlocked with the liquid level meter (51) module of the reflux tank (5) to adjust the content of each component in the reaction device. When the liquid level reaches an upper limit, the liquid is output through the reflux pump; when the liquid level drops, the reflux pump is turned off and the liquid stops being output.

[0014] Furthermore, the filtering device (8) comprises a filtering pump (81), a filtering component (82), and a flow meter (83).

[0015] Furthermore, the types of the filter assembly (82) typically include a flat plate stirring and filtering two-in-one machine, a flat plate stirring and heating filtering three-in-one machine, a cylindrical cone stirring and filtering two-in-one machine, a cylindrical cone stirring and heating filtering three-in-one machine, and a dynamic membrane filter.

[0016] Furthermore, a filtering device (8) is used to achieve concentration and separation of the solid catalyst.

[0017] Furthermore, the flow meter (83), the filter outlet, the synthetic liquid outlet and the concentrated liquid outlet are adjusted by the flow meter (83) to control the concentration ratio of the solid catalyst.

[0018] Furthermore, the stirred tank reactor (1) is provided with a jacket, and a heat-conducting medium is passed into the jacket.

[0019] Furthermore, the tower top secondary condenser (4) is connected to the exhaust port.

[0020] Furthermore, the reflux tank (5) is provided with a double-pass sight glass, and the double-pass sight glass is provided with a sight glass scale.

[0021] Compared with the prior art, the beneficial effects of the utility model are:

[0022] 1. The utility model provides a linkage device suitable for transesterification reaction control and solid catalyst filtration and recovery, which can significantly reduce the time of transesterification reaction, improve reaction efficiency and reduce energy consumption. In addition, the device has a simple structure and is easy to maintain.

[0023] 2. The content of each component in the reaction process is adjusted through interlocking control of the liquid level meter (51) of the reflux tank (5) and the reflux pump (6), thereby promoting the forward progress of the reaction and achieving substantially complete conversion of the raw materials.

[0024] 3. Filtering through the filtering device (8), the synthetic liquid enters the receiving tank (9), and the solid catalyst after concentration enters the reactor with stirring (1) and is applied to the next batch of synthesis; as the reaction proceeds, new esters are continuously generated and the concentration increases, and new alcohols are continuously removed from the reaction system. Compared with the initial state, the concentration of the catalyst is continuously increased and reaches an excess, which easily causes the new ester to undergo secondary reaction decomposition or generate impurities under the action of the catalyst; and the filtering component can, on the one hand, play a role in concentrating the catalyst, and can achieve control of the concentration amount. The system operates in a closed manner, so that the solid catalyst is filtered, concentrated, and recycled; on the other hand, a part of the catalyst can be stored in the filtering device to achieve the effect of reducing the catalyst concentration in the reaction system and achieve control of the catalyst concentration in the reaction phase. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The utility model is a structural schematic diagram of a linkage device suitable for controlling ester exchange reactions and filtering and recovering solid catalysts.

[0026] Explanation of the reference numerals: 1. Agitated kettle reactor; 2. Distillation separation tower; 3. First-stage condenser at the top of the tower; 4. Second-stage condenser at the top of the tower; 5. Reflux tank; 51. Liquid level meter; 6. Reflux pump; 7. Collection tank; 8. Filter device; 81. Filter pump; 82. Filter assembly; 83. Flow meter; 9. Receiving tank. DETAILED DESCRIPTION

[0027] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] Example

[0029] The preparation of vinyl carbonate by transesterification of 3,4-diol-1-butene with dimethyl carbonate is taken as an example for description of the embodiment.

[0030] The transesterification reaction between esters and alcohols can be represented by the following reaction equation:

[0031]

[0032] In this reaction, represents ester, R''OH represents alcohol, R'OH represents the new ester generated, and R'OH represents the new alcohol generated. The reaction is carried out under alkaline catalyst conditions, and the raw ester and alcohol react to generate new alcohol and ester. Since there is a chemical equilibrium in the transesterification reaction, if the transesterification reaction is to proceed in the forward direction, at least one of the following two conditions must be met: 1. The stability of the new ester generated is stronger than the previous ester; 2. The new alcohol generated can be continuously removed during the reaction.

[0033] A typical transesterification reaction is a method for synthesizing vinyl carbonate, in which 3,4-diol-1-butene and dimethyl carbonate undergo an ester exchange reaction to produce vinyl carbonate and methanol. The reaction equation is as follows:

[0034]

[0035] 3,4-diol-1-butene and dimethyl carbonate are heated and reacted under the action of a catalyst in a stirred reactor. As methanol is produced, the concentration of methanol increases, which is not conducive to the forward reaction. Therefore, it is necessary to continuously separate methanol from the reaction system. The simplest solution is that after distillation and vaporization, methanol and dimethyl carbonate are brought to the top of the tower, and a certain reflux ratio is controlled to separate methanol, and dimethyl carbonate continues to return to the reaction. In this way, by controlling the extracted materials and realizing the control of the component content of the materials in the kettle, the reaction is carried out in the forward direction.

[0036] During the reaction, the synthetic liquid containing the solid catalyst is separated through the filtration assembly by circulating through the filtration device and the filter pump. The synthetic filtered clear liquid enters the receiving tank, and the filtered concentrated circulating recovered liquid containing the solid catalyst remains in the reactor, thereby achieving the separation of the synthetic liquid and the solid catalyst.

[0037] A linkage device suitable for transesterification reaction control and solid catalyst filtration and recovery, comprising a stirred kettle reactor 1, a distillation separation tower 2, a first-level condenser 3 at the top of the tower, a second-level condenser 4 at the top of the tower, a reflux tank 5, a reflux pump 6, a collection tank 7, a filtering device 8 and a receiving tank 9. The reflux tank 5, the reflux pump 6 and the collection tank 7 are used to adjust the content of each component in the reaction process to promote the forward progress of the reaction. Through the filtering device 8, the solid catalyst is filtered, concentrated and recovered through the filtering component, the synthetic liquid enters the receiving tank, and the solid catalyst after concentration in the reactor enters the next batch of synthesis.

[0038] The stirred tank reactor 1 is provided with a jacket, into which steam or circulating water is introduced. A secondary condenser 4 at the top of the tower is connected to the exhaust port.

[0039] The reflux tank 5 is provided with a liquid level meter 51 and a double-pass sight glass, and the double-pass sight glass is provided with a sight glass scale.

[0040] The reflux pump 6 is interlocked with the liquid level gauge of the reflux tank 5. When the liquid level reaches the upper limit, the liquid is output through the reflux pump; when the liquid level drops, the reflux pump is closed and the liquid stops being output.

[0041] During the production operation, the new alcohol continuously generated during the reaction is continuously distilled and vaporized and then taken out to the top of the tower. The content of each component in the reaction device is determined through the interlocking control of the reflux tank 5, the reflux pump 6, the collection tank 7 and the liquid level meter 51, and a certain reflux ratio is controlled. Energy and material exchange are carried out in the tower section packing layer, the raw materials are pressed in the tower and the kettle, and the generated new alcohol is quantitatively extracted and collected in the collection tank. The amount of new alcohol in the kettle is reduced, the reaction is promoted to proceed in the forward direction, the target product is obtained, and the reverse reaction is reduced.

[0042] During the reaction, a filter device 8 is used, including a filter pump 81, a filter assembly 82, and a flow meter 83. As the reaction proceeds, new esters are continuously generated and their concentration increases, and new alcohols are continuously removed from the reaction system. Compared with the initial state, the concentration of the catalyst is continuously increased and reaches an excess, which may easily lead to secondary reaction decomposition or generation of impurities of the new esters under the action of the catalyst. By filtering and recovering, on the one hand, the catalyst can be concentrated during filtration, and the concentration amount can be controlled. Through the filter pump circulation, the synthetic liquid containing the solid catalyst is separated through the filter assembly, and the synthetic filtered clear liquid enters the receiving tank 9. The filtered, concentrated, and recycled liquid containing the solid catalyst is retained in the reactor to separate the synthetic liquid and the solid catalyst. The system is operated in a closed manner, so that the solid catalyst is filtered, concentrated, and recycled. On the other hand, a portion of the catalyst can be stored in the filter device 8 to reduce the catalyst concentration in the reaction system and control the catalyst concentration in the reaction phase.

[0043] After the catalyst and the synthetic liquid are separated, the synthetic liquid is collected and then enters the next batch of transesterification reaction. The receiving tank 9 is filled with solvent and reactants in sequence, then enters the filtering device and then enters the reactor for transesterification reaction.

[0044] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the utility model in detail. The above description is only a specific embodiment of the utility model and is not intended to limit the utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A linkage device suitable for controlling transesterification reaction and filtering and recovering solid catalyst, comprising: A stirred tank reactor (1), a distillation separation tower (2), a first-stage condenser (3) at the top of the tower, and a second-stage condenser (4) at the top of the tower, characterized in that: the reaction device also includes a reflux tank (5), a reflux pump (6), a collection tank (7), a filtering device (8) and a receiving tank (9), and the content of each component in the reaction process is adjusted by interlocking control of the reflux tank (5), the reflux pump (6) and the collection tank (7), so as to promote the forward progress of the reaction; during the reaction process, the filtering device (8) separates the synthetic liquid and the solid catalyst, so that the solid catalyst can be recycled.

2. A linkage device suitable for controlling transesterification reaction and filtering and recovering solid catalyst according to claim 1, characterized in that: The reflux tank (5) is provided with a liquid level meter (51).

3. A linkage device suitable for transesterification reaction control and solid catalyst filtration and recovery according to claim 2, characterized in that: The reflux pump (6) is interlocked with the liquid level meter (51) of the reflux tank (5), and interlocking control is performed through the liquid level meter (51) module to adjust the content of each component in the reaction device. When the liquid level reaches the upper limit, the liquid is output through the reflux pump; when the liquid level drops, the reflux pump is closed and the liquid stops being output.

4. A linkage device suitable for transesterification reaction control and solid catalyst filtration and recovery according to claim 1, characterized in that: The filtering device (8) comprises a filtering pump (81), a filtering component (82) and a flow meter (83).

5. A linkage device suitable for transesterification reaction control and solid catalyst filtration and recovery according to claim 4, characterized in that: Typical types of the filtering assembly (82) include a flat plate stirring and filtering two-in-one machine, a flat plate stirring and heating filtering three-in-one machine, a cylindrical cone stirring and filtering two-in-one machine, a cylindrical cone stirring and heating filtering three-in-one machine, and a dynamic membrane filter.

6. A linkage device suitable for transesterification reaction control and solid catalyst filtration and recovery according to claim 4 or 5, characterized in that: The filtering device (8) is used to achieve the concentration and separation of the solid catalyst.

7. A linkage device suitable for controlling transesterification reaction and filtering and recovering solid catalyst according to claim 1 or 2, characterized in that: The filtration outlet, synthetic liquid and concentrated liquid outlets are regulated by a flow meter (83) to control the concentration ratio.

8. The linkage device for controlling transesterification reaction and filtering and recovering solid catalyst according to claim 1, characterized in that: The stirred kettle reactor (1) is provided with a jacket, and a heat-conducting medium is introduced into the jacket.

9. The linkage device for controlling transesterification reaction and filtering and recovering solid catalyst according to claim 1, characterized in that: The tower top secondary condenser (4) is connected to the exhaust port.

10. The linkage device suitable for transesterification reaction control and solid catalyst filtration and recovery according to claim 1, characterized in that: The reflux tank (5) is provided with a double-pass sight glass, and the double-pass sight glass is provided with a sight glass scale.

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