Device for reducing impurity content of diethyl carbonate
The described process effectively reduces DEC impurity levels and energy consumption by pre-treating and distilling DEC using a series of towers and reactors, with heat recovery from tower residues.
Patent Information
- Application Number
- CN202422365111.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-27
- Publication Date
- 2025-07-15
- Estimated Expiration
- 2034-09-27
AI Technical Summary
During the preparation process of existing diethyl carbonate, impurities are difficult to remove, and steam heating energy consumption is high and production costs are high. It is impossible to separate impurities with similar boiling points of diethyl carbonate through distillation.
The device consisting of components such as reaction towers, separation towers, and distillation towers can reduce energy consumption and remove impurities through distillation and pre-reaction impurities, combined with heat recycling, and reduce energy consumption and remove impurities.
Effectively reduce the impurity content in diethyl carbonate, improve product quality, and significantly reduce energy consumption through heat recycling and improve economic benefits.
Smart Images
Figure CN223096768U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a device for preparing diethyl carbonate, in particular to a device for reducing the impurity content of diethyl carbonate. Background Technique
[0002] With the rapid development of new energy vehicles, the rapid development of the lithium-ion battery industry has been driven. Diethyl carbonate mainly plays the role of an electrolyte in lithium-ion batteries. It can form a complex with lithium salts to prepare an electrolyte solution, increasing the ionic conductivity of the electrolyte solution of lithium-ion batteries, thereby improving the performance of lithium-ion batteries; in addition, diethyl carbonate can also protect the electrode material, reduce the reaction between the electrode and the electrolyte solution, and extend the service life of lithium-ion batteries.
[0003] Currently, in the preparation process of diethyl carbonate (DEC), steam is generally used for preheating and heating, which has high energy consumption and high production costs. The reaction of dimethyl carbonate and absolute ethanol to generate diethyl carbonate through transesterification not only has obvious advantages over the traditional preparation method in terms of production safety and pollution reduction, but also greatly reduces the production cost. Moreover, due to the advantages of non-toxic raw materials and no three wastes pollution in the production process, there are impurities with boiling points close to that of diethyl carbonate, and it is impossible to separate them by distillation. Content of the Utility Model
[0004] The purpose of the utility model is to provide a device for reducing the impurity content of diethyl carbonate, aiming at the above-mentioned defects existing in the prior art, removing some impurities carried in the raw materials before the reaction, and reducing the impurity content in diethyl carbonate; in addition, the heat of the separation tower is recycled to heat the preheater, greatly reducing the energy consumption.
[0005] A device for reducing the impurity content of diethyl carbonate according to the present utility model has the following technical solution: It includes a reaction tower (T101), a separation tower (T102), a methyl ethyl carbonate rectification tower (T103), a dimethyl carbonate rectification tower (T104), an absolute ethanol rectification tower (T105), a diethyl carbonate rectification tower (T106), a second diethyl carbonate rectification tower (T107), a reactor (1), and a preheater (2). The top of the dimethyl carbonate rectification tower (T104) and the top of the absolute ethanol rectification tower (T105) are connected through a pipeline to the tube-side inlet of the preheater (2). The tube-side outlet of the preheater (2) is connected through a pipeline to the upper part of the reactor (1). The lower part of the reactor (1) is connected to the reaction tower (T101). The bottom of the reaction tower (T101) is connected through a pipeline to the side line of the separation tower (T102). The upper side of the separation tower (T102) is connected through a pipeline to the methyl ethyl carbonate rectification tower (T103). The bottom of the separation tower (T102) is connected through a pipeline to the shell-side inlet of the preheater (2). The shell-side outlet of the preheater (2) is connected through a pipeline to the diethyl carbonate rectification tower (T106).
[0006] Preferably, the middle part of the above-mentioned diethyl carbonate rectification tower (T106) is connected through a pipeline to the second diethyl carbonate rectification tower (T107).
[0007] Preferably, a first reboiler (a1) is provided at the bottom of the above-mentioned reaction tower (T101). The top of the reaction tower (T101) is connected through a pipeline to the tube-side inlet of the first condenser (3). The tube-side outlet of the first condenser (3) is connected through a pipeline to the first buffer tank (5). The lower end of the first buffer tank (5) is connected through a pipeline and a second circulation pump (b2) to the upper side of the reaction tower (T101).
[0008] Preferably, a second reboiler (a2) is provided at the bottom of the above-mentioned separation tower (T102). The top of the separation tower (T102) is connected through a pipeline to the tube-side inlet of the third condenser (8). The tube-side outlet of the third condenser (8) is connected through a pipeline to the second buffer tank (6). The lower end of the second buffer tank (6) is connected through a pipeline and a fourth circulation pump (b4) to the middle upper part of the separation tower (T102).
[0009] Preferably, the top of the above-mentioned methyl ethyl carbonate rectification tower (T103) is connected through a pipeline to the tube-side inlet of the second condenser (4). The tube-side outlet of the second condenser (4) is connected through a pipeline to the third buffer tank (7). The lower end of the third buffer tank (7) is connected through a pipeline and a sixth circulation pump (b6) to the upper side of the methyl ethyl carbonate rectification tower (T103).
[0010] Preferably, a fourth reboiler (a4) is provided at the bottom of the above-mentioned dimethyl carbonate rectification tower (T104), and a fifth reboiler (a5) is provided at the bottom of the absolute ethanol rectification tower (T105).
[0011] Preferably, a sixth reboiler (a6) is provided at the bottom of the above-mentioned diethyl carbonate rectification column (T106).
[0012] The beneficial effects of the present utility model are as follows: by removing some impurities carried in the raw materials before the reaction and further removing the impurities in the diethyl carbonate during the rectification stage, the present utility model effectively reduces the impurity content in the diethyl carbonate and improves the product quality; on the other hand, the heat of the preheater comes from the withdrawn liquid at the bottom of the separation column T102, realizing the recycling of heat, greatly reducing the energy consumption, and improving the economic benefits of the product. Description of the Drawings
[0013] Figure 1 is a schematic structural diagram of the first embodiment of the present utility model;
[0014] Figure 2 is a schematic structural diagram of the second embodiment of the present utility model;
[0015] In the above figures: reaction tower T101, separation tower T102, methyl ethyl carbonate rectification tower T103, dimethyl carbonate rectification tower T104, absolute ethanol rectification tower T105, diethyl carbonate rectification tower T106, second diethyl carbonate rectification tower T107, reactor 1, preheater 2, first condenser 3, second condenser 4, first buffer tank 5, second buffer tank 6, third buffer tank 7, third condenser 8;
[0016] First reboiler a1, second reboiler a2, third reboiler a3, fourth reboiler a4, fifth reboiler a5, sixth reboiler a6, seventh reboiler a7, first circulation pump b1, second circulation pump b2, third circulation pump b3, fourth circulation pump b4, fifth circulation pump b5, sixth circulation pump b6. Detailed Embodiments
[0017] The following describes the preferred embodiments of the present utility model with reference to the drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present utility model and are not used to limit the present utility model.
[0018] Example 1, referring to Figure 1, a device for reducing the impurity content of diethyl carbonate mentioned in the present utility model, includes a reaction tower T101, a separation tower T102, a methyl ethyl carbonate rectification tower T103, a dimethyl carbonate rectification tower T104, an absolute ethanol rectification tower T105, a diethyl carbonate rectification tower T106, a second diethyl carbonate rectification tower T107, a reactor 1, and a preheater 2. The top of the dimethyl carbonate rectification tower T104 and the top of the absolute ethanol rectification tower T105 are connected to the tube-side inlet of the preheater 2 through pipelines. The tube-side outlet of the preheater 2 is connected to the upper part of the reactor 1 through a pipeline. The lower part of the reactor 1 is connected to the reaction tower T101. The bottom of the reaction tower T101 is connected to the side line of the separation tower T102 through a pipeline. The upper side of the separation tower T102 is connected to the methyl ethyl carbonate rectification tower T103 through a pipeline. The bottom of the separation tower T102 is connected to the shell-side inlet of the preheater 2 through a pipeline. The shell-side outlet of the preheater 2 is connected to the diethyl carbonate rectification tower T106 through a pipeline.
[0019] A first reboiler a1 is provided at the bottom of the above-mentioned reaction tower T101. The top of the reaction tower T101 is connected to the tube-side inlet of the first condenser 3 through a pipeline. The tube-side outlet of the first condenser 3 is connected to the first buffer tank 5 through a pipeline. The lower end of the first buffer tank 5 is connected to the upper side of the reaction tower T101 through a pipeline and a second circulation pump b2.
[0020] A second reboiler a2 is provided at the bottom of the above-mentioned separation tower T102. The top of the separation tower T102 is connected to the tube-side inlet of the third condenser 8 through a pipeline. The tube-side outlet of the third condenser 8 is connected to the second buffer tank 6 through a pipeline. The lower end of the second buffer tank 6 is connected to the middle upper part of the separation tower T102 through a pipeline and a fourth circulation pump b4.
[0021] The top of the above-mentioned methyl ethyl carbonate rectification tower T103 is connected to the tube-side inlet of the second condenser 4 through a pipeline. The tube-side outlet of the second condenser 4 is connected to the third buffer tank 7 through a pipeline. The lower end of the third buffer tank 7 is connected to the upper side of the methyl ethyl carbonate rectification tower T103 through a pipeline and a sixth circulation pump b6.
[0022] A fourth reboiler a4 is provided at the bottom of the above-mentioned dimethyl carbonate rectification tower T104, and a fifth reboiler a5 is provided at the bottom of the absolute ethanol rectification tower T105.
[0023] A sixth reboiler a6 is provided at the bottom of the above-mentioned diethyl carbonate rectification tower T106.
[0024] When the utility model is in use, the raw material dimethyl carbonate (DMC) is fed into the side line of the dimethyl carbonate rectification column T104 for rectification and impurity removal first. The raw material absolute ethanol (ET) is fed into the side line of the absolute ethanol rectification column T105 for rectification and impurity removal as well. Then, it is preheated by the preheater 2. After the preheating is completed, it enters the reactor 1 for reaction to generate ethyl methyl carbonate, diethyl carbonate, and methanol. The mixture enters the reaction column T101 for continuous reaction. The dimethyl carbonate-methanol azeotrope is drawn from the top of the reaction column T101, and the mixture of ethyl methyl carbonate and diethyl carbonate is drawn from the bottom of the column and enters the separation column T102. Ethyl methyl carbonate is drawn from the top of the separation column T102 and sent to the ethyl methyl carbonate rectification column T103. The liquid drawn from the bottom of the separation column T102 is fed into the diethyl carbonate rectification column T106 for rectification to obtain diethyl carbonate with a higher purity.
[0025] Among them, the heat of the preheater 2 comes from the liquid drawn from the bottom of the separation column T102, realizing the recycling of heat and reducing energy consumption. In addition, some impurities carried in the raw materials are removed before the reaction, reducing the impurity content in the subsequent diethyl carbonate.
[0026] Embodiment 2: A device for reducing the impurity content of diethyl carbonate mentioned in the utility model includes a reaction column T101, a separation column T102, an ethyl methyl carbonate rectification column T103, a dimethyl carbonate rectification column T104, an absolute ethanol rectification column T105, a diethyl carbonate rectification column T106, a second diethyl carbonate rectification column T107, a reactor 1, and a preheater 2. The top of the dimethyl carbonate rectification column T104 and the top of the absolute ethanol rectification column T105 are connected to the tube-side inlet of the preheater 2 through pipelines. The tube-side outlet of the preheater 2 is connected to the upper part of the reactor 1 through a pipeline. The lower part of the reactor 1 is connected to the reaction column T101. The bottom of the reaction column T101 is connected to the side line of the separation column T102 through a pipeline. The upper side of the separation column T102 is connected to the ethyl methyl carbonate rectification column T103 through a pipeline. The bottom of the separation column T102 is connected to the shell-side inlet of the preheater 2 through a pipeline. The shell-side outlet of the preheater 2 is connected to the diethyl carbonate rectification column T106 through a pipeline.
[0027] The difference from Embodiment 1 is:
[0028] Refer to Figure 2 , and the middle part of the diethyl carbonate rectification column T106 is connected to the second diethyl carbonate rectification column T107 through a pipeline.
[0029] When the utility model is in use, the raw material dimethyl carbonate (DMC) is fed into the side line of the dimethyl carbonate rectification column T104 for rectification to remove impurities first. The raw material absolute ethanol (ET) is fed into the side line of the absolute ethanol rectification column T105 for rectification to remove impurities too. Then, it is preheated through the preheater 2 and enters the reactor 1 after the preheating is completed to react to generate ethyl methyl carbonate, diethyl carbonate and methanol. The mixture enters the reaction tower T101 to continue the reaction. The azeotrope of dimethyl ester and methanol is drawn from the top of the reaction tower T101, and the mixture of ethyl methyl carbonate and diethyl carbonate is drawn from the bottom of the tower and enters the separation tower T102. Ethyl methyl carbonate is drawn from the top of the separation tower T102 and sent to the ethyl methyl carbonate rectification column T103. The liquid drawn from the bottom of the separation tower T102 is fed into the diethyl carbonate rectification column T106 for rectification. Impurities are removed from the top of the diethyl carbonate rectification column T106, and the middle line is fed through a pipeline into the second diethyl carbonate rectification column T107 for continuous rectification, so as to obtain diethyl carbonate with higher purity. By removing some of the impurities carried in the raw materials before the reaction and further removing the impurities in the diethyl carbonate during the rectification stage, the utility model effectively reduces the impurity content in the diethyl carbonate and improves the product quality.
[0030] The above are only the preferred embodiments of the utility model. Any person skilled in the art may modify the utility model by using the technical solutions described above or modify it into equivalent technical solutions. Therefore, any simple modification or equivalent transformation made according to the technical solutions of the utility model falls within the scope of protection required by the utility model.
Claims
1. A device for reducing the impurity content of diethyl carbonate, characterized in that: It includes a reaction tower (T101), a separation tower (T102), an ethyl methyl carbonate rectification tower (T103), a dimethyl carbonate rectification tower (T104), an absolute ethanol rectification tower (T105), a diethyl carbonate rectification tower (T106), a second diethyl carbonate rectification tower (T107), a reactor (1), and a preheater (2). The top of the dimethyl carbonate rectification tower (T104) and the top of the absolute ethanol rectification tower (T105) are connected to the tube-side inlet of the preheater (2) through pipelines. The tube-side outlet of the preheater (2) is connected to the upper part of the reactor (1) through a pipeline. The lower part of the reactor (1) is connected to the reaction tower (T101). The bottom of the reaction tower (T101) is connected to the side line of the separation tower (T102) through a pipeline. The upper side of the separation tower (T102) is connected to the ethyl methyl carbonate rectification tower (T103) through a pipeline. The bottom of the separation tower (T102) is connected to the shell-side inlet of the preheater (2) through a pipeline. The shell-side outlet of the preheater (2) is connected to the diethyl carbonate rectification tower (T106) through a pipeline.
2. The device for reducing the impurity content of diethyl carbonate according to claim 1, characterized in that: The middle part of the diethyl carbonate rectification tower (T106) is connected to the second diethyl carbonate rectification tower (T107) through a pipeline.
3. A device for reducing the impurity content of diethyl carbonate according to claim 1 or 2, characterized in that: A first reboiler (a1) is provided at the bottom of the reaction tower (T101). The top of the reaction tower (T101) is connected to the tube-side inlet of the first condenser (3) through a pipeline. The tube-side outlet of the first condenser (3) is connected to the first buffer tank (5) through a pipeline. The lower end of the first buffer tank (5) is connected to the upper side of the reaction tower (T101) through a pipeline and a second circulation pump (b2).
4. The device for reducing the impurity content of diethyl carbonate according to claim 3, wherein: A second reboiler (a2) is provided at the bottom of the separation tower (T102). The top of the separation tower (T102) is connected to the tube-side inlet of the third condenser (8) through a pipeline. The tube-side outlet of the third condenser (8) is connected to the second buffer tank (6) through a pipeline. The lower end of the second buffer tank (6) is connected to the middle-upper part of the separation tower (T102) through a pipeline and a fourth circulation pump (b4).
5. The device for reducing the impurity content of diethyl carbonate according to claim 4, wherein: The top of the ethyl methyl carbonate rectification tower (T103) is connected to the tube-side inlet of the second condenser (4) through a pipeline. The tube-side outlet of the second condenser (4) is connected to the third buffer tank (7) through a pipeline. The lower end of the third buffer tank (7) is connected to the upper side of the ethyl methyl carbonate rectification tower (T103) through a pipeline and a sixth circulation pump (b6).
6. The device for reducing the impurity content of diethyl carbonate according to claim 5, characterized in that: A fourth reboiler (a4) is provided at the bottom of the dimethyl carbonate rectification tower (T104), and a fifth reboiler (a5) is provided at the bottom of the absolute ethanol rectification tower (T105).
7. The device for reducing the impurity content of diethyl carbonate according to claim 6, wherein: A sixth reboiler (a6) is provided at the bottom of the diethyl carbonate rectification tower (T106).