A process for purifying tetrahydrofuran using an electrolyte

Abstract

The application relates to a treatment device and method for purifying tetrahydrofuran by using electrolyte, and relates to the technical field of purification devices, which comprises a treatment tank, an inner tank, a water conveying pipeline, an electrolyte conveying mechanism, a driving piece and a three-stage evaporator; a partition cover is arranged in the treatment tank; the electrolyte conveying mechanism is movably inserted in the partition cover and arranged at the lower end of the inner tank; a liquid discharge valve is arranged on the lower end surface of the inner tank; the inner tank is rotationally matched with the treatment tank under the driving of the driving piece; a condenser is connected with the treatment tank through the water conveying pipeline; a discharge pipe is arranged between the lower end of the treatment tank and the three-stage evaporator; and the lower end of the condenser is connected with the steam outlet of the three-stage evaporator through a pipeline. The application has the advantages of reasonable and compact structure, simple process, easy operation, good separation and purification effect, small energy consumption and repeated utilization of resources.

Description

Technical Field

[0001] This invention belongs to the field of purification equipment technology, specifically relating to a processing device and method for purifying tetrahydrofuran using electrolytes. Background Technology

[0002] Tetrahydrofuran is a colorless, water-miscible organic liquid with low viscosity at room temperature and pressure. Its main use is as a precursor for high molecular weight polymers. Methyl tert-butyl ether (MTBE) is an organic compound with the chemical formula [missing information - likely a chemical formula], a colorless and transparent liquid, insoluble in water but readily soluble in ethanol and ether. It is an excellent high-octane gasoline additive and antiknock agent.

[0003] In chemical production processes, a mixed solution of methyl tert-butyl ether (MTBE) and tetrahydrofuran is often formed, which requires further separation and purification to achieve resource recycling. Since MTBE is insoluble in water and tetrahydrofuran is miscible with water, water can be added to the mixed solution of MTBE and tetrahydrofuran to separate the MTBE and tetrahydrofuran first, and then the tetrahydrofuran aqueous solution can be further dehydrated and purified.

[0004] Existing dehydration systems for tetrahydrofuran (THF) are mostly distillation units. However, since THF is miscible with water, the dehydration accuracy using distillation is limited, and the distillation units are complex and expensive to operate. Furthermore, adsorption filtration cannot remove other harmful components (such as peroxides) from THF. Therefore, both of these separation methods suffer from problems such as complex separation processes, difficulty in operation, low product recovery rates, low separation purity, and secondary pollution. To address these issues, we propose a treatment device and method for purifying THF using electrolytes. Summary of the Invention

[0005] The purpose of this invention is to provide an apparatus and method for purifying tetrahydrofuran using an electrolyte in order to solve the above-mentioned problems.

[0006] The present invention achieves the above objectives through the following technical solutions:

[0007] This invention provides an activated carbon regeneration and circulation device for waste gas treatment, comprising a treatment tank, an inner tank, a water supply pipeline, an electrolyte delivery mechanism, a driving component, and a three-stage evaporator;

[0008] The processing tank is equipped with a partition cover inside. The electrolyte delivery mechanism is movably inserted into the partition cover and is located at the lower end of the inner tank. The lower end face of the inner tank is equipped with a drain valve. The inner tank rotates with the processing tank under the drive of the driving component.

[0009] The processing tank top end is connected with a condenser through a water delivery pipeline, and the lower end is connected with a discharge pipe between the third evaporator.

[0010] As a further optimization scheme of the application, the water delivery pipeline comprises a main pipeline, a backflow pipeline connecting the condenser and the inner tank, and a metering valve arranged on the backflow pipeline

[0011] As a further optimization scheme of the application, the processing tank upper end is provided with a feed pipe rotatably connected with the inner tank, and a pipeline booster is arranged on the feed pipe, a methyl tert-butyl ether discharge pipe provided with a vacuum pump is arranged to penetrate through the feed pipe, and one end of the methyl tert-butyl ether discharge pipe is arranged to penetrate into the inner tank and is close to the inner bottom wall of the inner tank

[0012] As a further optimization scheme of the application, the driving member comprises a driving motor arranged at the top end of the processing tank, and a driving gear set is arranged at the center of the top end of the inner tank and connected with the driving motor driving end and the driven end

[0013] As a further optimization scheme of the application, the electrolyte conveying mechanism comprises a receiving cover movably inserted into the partition cover and having an opening upward, a discharge pipe arranged on the side wall of the processing tank and close to the opening of the receiving cover, a flow guide ring arranged on the inner side wall of the receiving cover, and a flow guide cover arranged on the side surface of the lower end of the inner tank and corresponding to the flow guide ring

[0014] As a further optimization scheme of the application, the processing tank is connected with an activated carbon adsorption box below the partition cover on one side, and the lower end of the third evaporator is provided with a scraper feeder.

[0015] The application also provides a processing method for purifying tetrahydrofuran by using electrolyte, comprising the following steps:

[0016] S1, the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent is sent into the inner tank, the water is delivered to the inner tank through the water delivery pipeline, the weight ratio of the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent to water is 1:1-3, the driving member drives the inner tank to rotate, the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent and water are fully mixed, and then the mixture is placed for 60-120 min, and the temperature is controlled to be 25-40℃;

[0017] S2, after the placement is completed, the inner tank is layered, the upper layer is methyl tert-butyl ether, and the lower layer is tetrahydrofuran aqueous solution, the discharge valve is opened, the lower layer solution is sent to the processing tank below the partition cover, and the upper layer solution is collected separately;

[0018] S3, the driving member drives the inner tank to continue rotating, and the electrolyte conveying mechanism conveys electrolyte to the partition cover position of the treatment tank, and the electrolyte is dispersed into the tetrahydrofuran aqueous solution under the rotation of the inner tank, until the electrolyte is saturated in the tetrahydrofuran aqueous solution and precipitates, and after standing for 60-120 min, stratification occurs, the upper layer is tetrahydrofuran, which is collected separately, and the lower layer is a supersaturated electrolyte aqueous solution;

[0019] S4, while step S3 is being performed, step S1 is performed.

[0020] As a further optimization scheme of the present application, step S5 is further included, the supersaturated electrolyte aqueous solution obtained in step S3 is sent to the third evaporator through the discharge pipe for three-stage evaporation, the electrolyte is discharged from the lower end of the third evaporator and reused, and the water vapor is conveyed to the condenser along the upper end of the third evaporator for condensation and backflow to the water conveying pipeline.

[0021] As a further optimization scheme of the present application, in step S2, the electrolyte includes but is not limited to sodium chloride and potassium chloride.

[0022] The present application has the following advantages:

[0023] (1) The treatment device of the present application has a reasonable and compact structure, and can integrally realize the separation of waste methyl tert-butyl ether and tetrahydrofuran mixed solvent and the purification of tetrahydrofuran, has good separation and purification effect, small energy consumption, and can realize resource reuse.

[0024] (2) The treatment method of the present application uses electrolyte to purify tetrahydrofuran, which has simple process operation, less energy consumption, and good effect compared with the purification methods of rectification, adsorption and filtration. BRIEF DESCRIPTION OF DRAWINGS

[0025] Fig. 1 The overall structure schematic diagram provided by the present application is shown in the figure;

[0026] Fig. 2 The internal structure schematic diagram of the treatment tank provided by the present application is shown in the figure;

[0027] In the figure: 1, treatment tank; 2, partition cover; 3, inner tank; 4, water conveying pipeline; 41, main pipeline; 42, backflow pipeline; 43, metering valve; 5, liquid discharge valve; 6, three-stage evaporator; 7, scraper feeder; 8, electrolyte conveying mechanism; 81, receiving cover; 82, flow guide ring; 83, discharge pipe; 84, flow guide cover; 9, discharge pipe; 10, methyl tert-butyl ether discharge pipe; 11, feed pipe; 12, vacuum pump; 13, driving motor; 14, driving gear set; 15, pipeline booster; 16, activated carbon adsorption tank; 17, condenser. DETAILED DESCRIPTION

[0028] The present application will now be described in further detail with reference to the accompanying drawings. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0029] Example 1

[0030] like Figs. 1-2 As shown, a processing device for purifying tetrahydrofuran using electrolytes includes a processing tank 1, an inner tank 3, a water pipeline 4, an electrolyte conveying mechanism 8, a driving component, and a three-stage evaporator 6.

[0031] The processing tank 1 is provided with a partition cover 2 inside. The electrolyte conveying mechanism 8 is movably inserted into the partition cover 2 and is set at the lower end of the inner tank 3. The lower end face of the inner tank 3 is provided with a drain valve 5. The inner tank 3 rotates with the processing tank 1 under the drive of the driving component.

[0032] The top of the treatment tank 1 is connected to a condenser 17 via a water supply pipe 4, and the bottom is connected to a discharge pipe 9 between the condenser 17 and the three-stage evaporator 6. The bottom of the condenser 17 is connected to the steam outlet of the three-stage evaporator 6 via a pipe.

[0033] Furthermore, the water supply pipeline 4 includes a main pipeline 41, a return pipeline 42 connecting the condenser 17 and the inner tank 3, and a metering valve 43 installed on the return pipeline 42. The main pipeline 41 is used for water supply, the return pipeline 42 is used to supply the water condensed by the condenser 17 into the inner tank 3 for use, and the metering valve 43 is used to accurately control the water supply volume.

[0034] Furthermore, the upper end of the processing tank 1 is provided with a feed pipe 11 rotatably connected to the inner tank 3. The feed pipe 11 is used to transport the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent to be treated, and the feed pipe 11 is provided with a pipeline pressure booster 15 for pressurization, which can pressurize the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent into the inner tank 3. A methyl tert-butyl ether discharge pipe 10 equipped with a vacuum pump 12 extends through the inside of the feed pipe 11 for discharging the methyl tert-butyl ether separated from the tetrahydrofuran. One end of the methyl tert-butyl ether discharge pipe 10 extends into the interior of the inner tank 3 near the inner bottom wall of the inner tank 3. After the tetrahydrofuran aqueous solution is emptied from the inner tank 3, the remaining methyl tert-butyl ether in the inner tank 3 is discharged under the suction action of the vacuum pump 12.

[0035] Furthermore, the driving component includes a drive motor 13 located at the top of the processing tank 1 and a drive gear set 14 whose active end is connected to the drive end of the drive motor 13 and whose driven end is axially connected to the center of the top of the inner tank 3. In use, the drive motor 13 drives the drive gear set 14 to drive the inner tank 3 to rotate at a uniform speed.

[0036] Further, the electrolyte conveying mechanism 8 comprises a receiving cover 81 which is movably inserted into the partition cover 2 and has an opening facing upward, a discharge pipe 83 which is arranged on the side wall of the processing tank 1 near the opening of the receiving cover 81, a flow guide ring 82 which is arranged on the inner side wall of the receiving cover 81, and a flow guide cover 84 which is arranged on the lower end side of the inner tank 3 and corresponds to the flow guide ring 82. In use, the electrolyte is conveyed into the receiving cover 81 through the discharge pipe 83. With the uniform rotation of the inner tank 3, the flow guide cover 84 on the lower end side of the inner tank 3 uniformly disperses the electrolyte into the tetrahydrofuran aqueous solution at the lower end of the processing tank 1.

[0037] Further, the processing tank 1 is connected to the activated carbon adsorption box 16 at one side below the partition cover 2. The separated tetrahydrofuran is discharged from the activated carbon adsorption box 16, which can achieve further adsorption and purification. The lower end of the three-stage evaporator 6 is provided with the scraper feeder 7. The evaporated and crystallized electrolyte is attached to the scraper feeder 7. Under the driving of the scraper feeder 7, the electrolyte is scraped and discharged, which realizes collection and reuse.

[0038] Working principle: The waste methyl tert-butyl ether and tetrahydrofuran mixed solvent is fed through the feed pipe 11. The pipeline booster 15 pressurizes the feed pipe 11, so that the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent is pressed into the inner tank 3. At the same time, water is fed into the inner tank 3 through the metering valve 43 of the main pipeline 41. The driving member is started. The driving motor 13 controls the driving gear set 14 to drive, which realizes the uniform rotation of the inner tank 3 in the processing tank 1. At the same time, the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent is fully mixed with water. Then, the rotation of the inner tank 3 is stopped, and the inner tank 3 is placed.

[0039] After the placement is completed, the inner tank 3 is layered into upper and lower layers. The upper layer is methyl tert-butyl ether, and the lower layer is tetrahydrofuran aqueous solution. The discharge valve 5 is opened to send the lower layer to the position below the partition cover 2 of the processing tank 1. The upper layer is pumped out of the inner tank 3 by the vacuum pump 12 and is separately collected.

[0040] The driving member drives the inner tank 3 to continue rotating. The electrolyte is conveyed to the position of the partition cover 2 of the processing tank 1 by the electrolyte conveying mechanism 8. The electrolyte is dispersed into the tetrahydrofuran aqueous solution under the rotation of the inner tank 3. Until the electrolyte is saturated in the tetrahydrofuran aqueous solution, the electrolyte is separated into upper and lower layers after being placed for 60-120 minutes. The upper layer is tetrahydrofuran, which is pumped into the activated carbon adsorption box 16 for further adsorption and purification, so as to obtain tetrahydrofuran with high purity. The lower layer is a supersaturated electrolyte aqueous solution, which is conveyed to the three-stage evaporator 6 through the discharge pipe 9 for evaporation. The evaporated and crystallized electrolyte is attached to the scraper feeder 7. The electrolyte is scraped and discharged by the scraper feeder 7, which realizes collection. The collected electrolyte can be reused. At the same time, the vapor is conveyed to the condenser 17 along the upper end of the three-stage evaporator 6, is condensed, and is returned to the reflux pipeline 42 for reuse.

[0041] The processing device of the present application is compact in structure arrangement, and can integrally realize separation of waste methyl tert-butyl ether and tetrahydrofuran mixed solvent and purification of tetrahydrofuran, has good separation and purification effect, small energy consumption and can realize resource recycling.

[0042] Example 2

[0043] The present embodiment also provides a processing method for purifying tetrahydrofuran by using electrolyte, comprising the following steps:

[0044] S1, the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent is sent into the inner tank 3, and the water is sent to the inner tank 3 through the water pipeline 4, the weight ratio of the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent to water is 1:1-3, the driving part drives the inner tank 3 to rotate to make the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent and water fully mixed, then the temperature is controlled at 25-40℃ for 60-120min;

[0045] S2, after the standing is completed, the inner tank 3 appears upper and lower stratification, the upper solution is methyl tert-butyl ether, and the lower solution is tetrahydrofuran aqueous solution, the lower solution is sent to the processing tank 1 under the separation cover 2, and the upper solution is collected separately;

[0046] S3, the driving part drives the inner tank 3 to continue to rotate, the electrolyte is sent to the separation cover 2 of the processing tank 1 by the electrolyte conveying mechanism 8, the electrolyte is dispersed into the tetrahydrofuran aqueous solution under the rotation of the inner tank 3, until the electrolyte is saturated in the tetrahydrofuran aqueous solution and precipitates, after standing for 60-120min, stratification appears, the upper solution is tetrahydrofuran, which is collected separately, and the lower solution is supersaturated electrolyte aqueous solution;

[0047] S4, step S1 is performed at the same time as step S3.

[0048] It also includes step S5, the supersaturated electrolyte aqueous solution obtained in step S3 is sent to the three-stage evaporator 6 through the discharge pipe 9 for three-stage evaporation, the electrolyte is discharged from the lower end of the three-stage evaporator 6 and is recycled, and the water vapor is sent to the condenser 17 along the upper end of the three-stage evaporator 6 for condensation and backflow to the water pipeline 4.

[0049] In the step S2, the electrolyte includes but is not limited to sodium chloride and potassium chloride.

[0050] In order to verify the superiority of the processing method for purifying tetrahydrofuran by using electrolyte by the device as described in example 1, the present embodiment provides the following examples:

[0051] Example 1

[0052] The methyl tert-butyl ether and tetrahydrofuran mixed solvent 10L (the volume ratio of methyl tert-butyl ether to tetrahydrofuran is 1:1) is sent into the inner tank 3, water is sent into the inner tank 3 through the water conveying pipeline 4, the water amount is 30L, the driving member drives the inner tank 3 to rotate to make the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent and water fully mixed, then the temperature is controlled to be 25℃ after standing for 60min; after standing, the upper and lower layers appear in the inner tank 3, the lower layer solution tetrahydrofuran aqueous solution is sent to the treatment tank 1 below the separation cover 2 position, the upper layer solution is collected separately; the driving member drives the inner tank 3 to continue to rotate, the potassium chloride is conveyed to the separation cover 2 position of the treatment tank 1 by the electrolyte conveying mechanism 8, the electrolyte is dispersed into the tetrahydrofuran aqueous solution under the rotation of the inner tank 3, until the electrolyte is saturated in the tetrahydrofuran aqueous solution and precipitates, after standing for 60min, the upper layer solution tetrahydrofuran is collected separately and sent to the activated carbon adsorption box 16 for further adsorption and purification, the finished product tetrahydrofuran is obtained, through detection, the yield of methyl tert-butyl ether is 99.9%, the yield of tetrahydrofuran is 99.9%, the purity of tetrahydrofuran is 99.8%, and the water content is 0.05%.

[0053] Example 2

[0054] The methyl tert-butyl ether and tetrahydrofuran mixed solvent 10L (the volume ratio of methyl tert-butyl ether to tetrahydrofuran is 1:1) is sent into the inner tank 3, water is sent into the inner tank 3 through the water conveying pipeline 4, the water amount is 10L, the driving member drives the inner tank 3 to rotate to make the waste methyl tert-butyl ether and tetrahydrofuran mixed solvent and water fully mixed, then the temperature is controlled to be 40℃ after standing for 60min; after standing, the upper and lower layers appear in the inner tank 3, the lower layer solution tetrahydrofuran aqueous solution is sent to the treatment tank 1 below the separation cover 2 position, the upper layer solution is collected separately; the driving member drives the inner tank 3 to continue to rotate, the sodium chloride is conveyed to the separation cover 2 position of the treatment tank 1 by the electrolyte conveying mechanism 8, the electrolyte is dispersed into the tetrahydrofuran aqueous solution under the rotation of the inner tank 3, until the electrolyte is saturated in the tetrahydrofuran aqueous solution and precipitates, after standing for 60min, the upper layer solution tetrahydrofuran is collected separately, through detection, the yield of methyl tert-butyl ether is 99.9%, the yield of tetrahydrofuran is 99.8%, the purity of tetrahydrofuran is 99.7%, and the water content is 0.08%.

[0055] Therefore, it can be seen that the device of the application can separate methyl tert-butyl ether and tetrahydrofuran by using electrolyte to purify tetrahydrofuran, the yield of tetrahydrofuran can reach 99.8-99.9%, the purity can reach 99.8%, and the water content is less than 0.1%, which can realize the recycling and application of tetrahydrofuran, has high economic value, and has good industrial application prospect.

[0056] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are within the protection scope of the present application.

Claims

1. A treatment apparatus for purifying tetrahydrofuran using an electrolyte, characterized by: The application relates to a treatment method for purifying tetrahydrofuran by electrolyte, which comprises the following steps: S1, sending waste methyl tert-butyl ether and tetrahydrofuran mixed solvents into an inner tank (3), feeding water into the inner tank (3) through a water feeding pipeline (4), the weight ratio of the waste methyl tert-butyl ether and tetrahydrofuran mixed solvents to water being 1:1-3, driving the inner tank (3) to rotate to make the waste methyl tert-butyl ether and tetrahydrofuran mixed solvents and water fully mixed, and then standing for 60-120 min with the temperature being controlled to be 25-40 DEG C; S2, after standing, upper and lower layers are formed in the inner tank (3), the upper layer is methyl tert-butyl ether, the lower layer is a tetrahydrofuran aqueous solution, the lower layer solution is sent to a treatment tank (1) below a partition cover (2) by opening a liquid discharge valve (5), and the upper layer solution is separately collected; S3, the inner tank (3) is continuously driven to rotate by a driving element, electrolyte is fed to the partition cover (2) of the treatment tank (1) by an electrolyte feeding mechanism (8), the electrolyte is dispersed into the tetrahydrofuran aqueous solution under the rotation of the inner tank (3), until the electrolyte is saturated and precipitates in the tetrahydrofuran aqueous solution, after standing for 60-120 min, upper and lower layers are formed, the upper layer is tetrahydrofuran and is separately collected, and the lower layer is a supersaturated electrolyte aqueous solution; S4, the step S1 is simultaneously performed with the step S3. The water feeding pipeline (4) comprises a main pipeline (41), a reflux pipeline (42) connecting the condenser (17) and the inner tank (3), and a metering valve (43) arranged on the reflux pipeline (42). The top end of the treatment tank (1) is provided with a feed pipe (11) which is rotationally connected with the inner tank (3), the feed pipe (11) is provided with a pipeline booster (15), a methyl tert-butyl ether discharge pipe (10) provided with a vacuum pump (12) is arranged in the feed pipe (11), and one end of the methyl tert-butyl ether discharge pipe (10) extends into the inner tank (3) and is close to the inner bottom wall of the inner tank (3). The driving element comprises a driving motor (13) arranged at the top end of the treatment tank (1), a driving gear set (14) which is rotationally connected with the driving motor (13) and is arranged at the top end center of the inner tank (3).

2. The apparatus for purifying tetrahydrofuran using an electrolyte according to claim 1, characterized by: ​ 3. The apparatus for purifying tetrahydrofuran using an electrolyte according to claim 1, wherein: ​ 4. The apparatus for purifying tetrahydrofuran using an electrolyte according to claim 1, wherein: ​ 5. The apparatus for purifying tetrahydrofuran using an electrolyte according to claim 1, wherein: The electrolyte conveying mechanism (8) comprises a receiving cover (81) movably connected with the partition cover (2) and having an opening facing upward, a discharge pipe (83) arranged on the side wall of the processing tank (1) near the opening of the receiving cover (81), a flow guide ring (82) arranged on the inner side wall of the receiving cover (81), and a flow guide cover (84) arranged on the lower end side of the inner tank (3) corresponding to the flow guide ring (82).

6. The apparatus for purifying tetrahydrofuran using an electrolyte according to claim 1, wherein: The processing tank (1) is connected with an activated carbon adsorption box (16) at one side below the partition cover (2), and the lower end of the three-stage evaporator (6) is provided with a scraper feeder (7).

7. The apparatus for purifying tetrahydrofuran using an electrolyte according to claim 1, wherein: The method further comprises the step S5 of sending the supersaturated electrolyte aqueous solution obtained in the step S3 to the three-stage evaporator (6) through the discharge pipe (9) to perform three-stage evaporation, so that the electrolyte is discharged from the lower end of the three-stage evaporator (6) and reused, and water vapor is conveyed along the upper end of the three-stage evaporator (6) to the condenser (17) to be condensed and returned to the water conveying pipeline (4).

8. The apparatus for purifying tetrahydrofuran using an electrolyte according to claim 1, wherein: In the step S3, the electrolyte includes but is not limited to sodium chloride and potassium chloride.

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