Process for extracting electronic-grade isopropanol from industrial isopropanol

Abstract

The invention belongs to the technical field of isopropanol production, and particularly relates to a process for extracting electronic-grade isopropanol from industrial isopropanol, which comprises the following steps: S1, pre-filtering a raw material to remove large-particle impurities, and sequentially removing light components and heavy components from the raw material isopropanol to obtain a secondary raw material; s2, inputting the second-stage raw material into a dehydration processor for dehydration to obtain a third-stage raw material; s3, inputting the third-stage raw material into an ion tank to remove metal ions contained in the third-stage raw material so as to obtain a fourth-stage raw material; s4, inputting the fourth-grade raw material into filtering and separating equipment to remove impurity particles in the fourth-grade raw material, so as to obtain an electronic-grade isopropanol product; heat in the extraction process can be fully utilized, energy consumption in the refining process can be reduced, meanwhile, water vapor condensation and liquefaction are promoted in the auxiliary dehydrator, water vapor component partial pressure on the other side of the membrane is reduced, water dehydration is promoted, and the dehydration effect and efficiency are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of isopropanol production, in particular to a process for extracting electronic-grade isopropanol from industrial isopropanol. Background Art

[0002] Electronic grade isopropyl alcohol is mainly used for ultra-clean cleaning and drying in the processing of precision electronic components such as chips, liquid crystals, magnetic heads, circuit boards, and as an ultra-clean cleaning organic solvent for clean room equipment. Among them, the product quality of electronic grade isopropyl alcohol seriously affects the yield rate of precision electronic components. When isopropyl alcohol contains trace metal elements, it is easy to cause integrated circuits or semiconductor components to be broken down, affecting the life of the product.

[0003] At present, the price difference between electronic-grade isopropyl alcohol and industrial-grade isopropyl alcohol is significant. Industrial-grade isopropyl alcohol is usually used as raw material, and electronic-grade isopropyl alcohol is obtained after more sophisticated separation, refining and purification. The main technical difficulty in producing electronic-grade isopropyl alcohol is that the water content is required to be less than 100ppm, and the impurity content of acetone, isopropyl ether and other impurities is less than 3ppm. Ordinary isopropyl alcohol has a water content of about 3000ppm and also contains about 200ppm of impurities such as acetone and isopropyl ether. Isopropyl alcohol and water are miscible, and the distillation separation process will form an azeotrope, which not only consumes a huge amount of energy, but is also difficult to dehydrate to below 200ppm.

[0004] In the prior art, the technology of refining isopropanol by distillation, gas phase high temperature adsorption or molecular sieve membrane consumes huge energy and requires high equipment investment. Summary of the invention

[0005] In order to make up for the shortcomings of the prior art, make full use of the heat in the extraction process, reduce the energy consumption in the refining process, and at the same time, promote the condensation and liquefaction of water vapor in the auxiliary dehydrator, reduce the partial pressure of the water vapor component on the other side of the membrane, promote the removal of water, and improve the removal effect and efficiency, the present invention proposes a process for extracting electronic grade isopropyl alcohol from industrial isopropyl alcohol.

[0006] The technical solution adopted by the present invention to solve the technical problem is: a process for extracting electronic grade isopropanol from industrial isopropanol according to the present invention comprises the following steps: S1: performing multi-stage pre-filtration treatment on the raw material isopropyl alcohol to remove large particle impurities in the raw material isopropyl alcohol, and then performing light fractionation and heavy fractionation on the raw material isopropyl alcohol to remove light components and heavy components contained in the raw material isopropyl alcohol to obtain a secondary raw material; S2: The secondary raw material is input into a dehydration adsorption device for processing, and the moisture contained in the material is removed to obtain a tertiary raw material: the material is first sent into a dehydration tower, and the vaporized material distilled from the dehydration tower is directly sent into an auxiliary dehydrator, and the remaining moisture in the material is removed through a permeation vaporization membrane; wherein a detector and a temporary storage tank are arranged behind the auxiliary dehydrator: the tertiary raw material that fails the moisture content test is stored in a temporary storage tank, and then the material in the temporary storage tank is input into the dehydration tower for circulation, and the tertiary raw material that passes the moisture content test is directly transported from the temporary storage tank to subsequent processing equipment; S3: Inputting the tertiary raw material into an ion tank to remove the metal ions contained therein to obtain a quaternary raw material; S4: Inputting the quaternary raw material into a filtering and separation device to remove impurity particles therein to obtain an electronic grade isopropyl alcohol product; Wherein, in step S1, the components with lower and higher boiling points than isopropanol are light components and heavy components respectively; in step S1, the raw material isopropanol is de-lightened and de-heaved by a multi-stage distillation tower; the ion tank and the filtering and separation equipment in steps S3 and S4 are multi-stage series-arranged; the ion tank is filled with ion exchange resin; Wherein, the water absorption and desorption device comprises a dehydration tower and an auxiliary dehydrator, and the product outlet on the dehydration tower is connected to the auxiliary dehydrator; An upper isolation plate and a lower isolation plate are installed in the auxiliary dehydrator from top to bottom, and the upper isolation plate and the lower isolation plate divide the space in the auxiliary dehydrator from top to bottom into a separation chamber, a heat exchange chamber and an extension chamber, and an insulation layer is installed outside the auxiliary dehydrator; The separation chamber is provided with a feed inlet and a discharge inlet, the heat exchange chamber is provided with an input inlet and an output inlet, and the seepage chamber is provided with a seepage liquid inlet; A fixed plate is installed in the separation chamber, a seepage vaporization membrane tube is installed between the fixed plate and the lower isolation plate, a heat pipe is installed in the seepage vaporization membrane tube, the upper end of the heat pipe passes through the upper isolation plate and is located in the heat exchange chamber, the heat pipe is fixed by the upper isolation plate, the space between the fixed plate and the upper isolation plate is an air pumping chamber, an air pumping port is installed in the air pumping chamber, the air pumping chamber and the seepage chamber are interconnected through the seepage vaporization membrane tube, and a retaining ring is installed on the part of the heat pipe located in the air pumping chamber.

[0007] Preferably, a limiting frame is installed in the seepage vaporization membrane tube, and the limiting frame clamps and fixes the heat pipe; The surfaces of the heat pipe and the limiting frame are provided with a hydrophobic coating.

[0008] Preferably, a groove is provided on the surface of the heat pipe, and a protrusion is provided on the limiting frame, and the protrusion and the groove cooperate with each other; A deformation sheet is installed on the limiting frame, and the deformation sheet is a bimetallic sheet.

[0009] Preferably, a vibration plate is installed in the separation chamber, a connecting rod is installed on the vibration plate, and two ends of the connecting rod are respectively connected to the fixed plate and the lower isolation plate; The vibration plate is arranged in a plurality of groups in the separation chamber, each group of the vibration plate is composed of a plurality of units from top to bottom, and the vibration plate is located near the seepage vaporization membrane tube.

[0010] Preferably, the connecting rod is located near the middle of the vibration plate, and the installation positions of the connecting rods on each group of the vibration plate are different.

[0011] Preferably, an elastic sleeve is installed on the connecting rod, the vibration plates on the connecting rod are fixed by the elastic sleeve, and the vibration plates are slidably installed on the connecting rod.

[0012] Preferably, the vibration plate is provided with evenly distributed through holes.

[0013] Preferably, an elastic thread is installed on the side surface of the vibration plate, and the elastic thread contacts the surface of the seepage vaporization membrane tube.

[0014] The beneficial effects of the present invention are as follows: 1. The process for extracting electronic-grade isopropyl alcohol from industrial isopropyl alcohol of the present invention fully utilizes the heat carried by the material from the dehydration tower through the cooperation between the dehydration tower and the auxiliary dehydrator, and performs heat exchange on the raw material isopropyl alcohol in the auxiliary dehydrator to increase the temperature of the raw material isopropyl alcohol, thereby fully utilizing the heat in the extraction process, reducing the energy consumption in the refining process, and improving the effect and efficiency of extracting electronic-grade isopropyl alcohol.

[0015] 2. The process for extracting electronic-grade isopropyl alcohol from industrial isopropyl alcohol described in the present invention comprises a seepage vaporization membrane tube, a heat pipe, a heat exchange chamber, and a limit frame, so that the water entering the seepage vaporization membrane tube will condense and liquefy after contacting the surface of the heat pipe, thereby further reducing the component partial pressure of the water inside the seepage vaporization membrane tube, thereby promoting the removal of water from the material and improving the efficiency and effect of dehydration.

[0016] 3. The process for extracting electronic-grade isopropyl alcohol from industrial isopropyl alcohol described in the present invention provides a vibrating plate, a connecting rod, an elastic sleeve and a through hole, so that the vibrating plate vibrates to stir and disturb the material, promotes uniform distribution of the material, avoids concentration polarization near the seepage vaporization membrane tube, prevents clogging of the permeation membrane, and improves the dehydration effect and efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings.

[0018] Figure 1 This is a schematic diagram of the process principle for extracting electronic grade isopropanol according to the present invention; Figure 2 It is a process flow diagram of the present invention; Figure 3 It is a front view of the auxiliary dehydrator in the present invention; Figure 4 It is a structural schematic diagram of the auxiliary dehydrator in the present invention; Figure 5 It is a schematic diagram of the structure of the vibrating plate and the connecting rod in the auxiliary dehydrator of the present invention; Figure 6 It is a schematic diagram of the installation of the seepage vaporization membrane tube and the heat pipe in the auxiliary dehydrator of the present invention; In the figure: light removal tower 1, heavy removal tower 2, dehydration tower 3, auxiliary dehydrator 4, separation chamber 41, feed inlet 411, air extraction port 412, discharge port 413, fixed plate 414, seepage chamber 42, seepage liquid port 421, lower isolation plate 422, heat exchange chamber 43, input port 431, output port 432, upper isolation plate 433, seepage vaporization membrane tube 44, vibration plate 45, connecting rod 451, elastic pipe sleeve 452, through hole 453, heat pipe 46, groove 461, limit frame 462, deformation plate 463, retaining ring 464, ion tank 5, filtering and separation equipment 6. DETAILED DESCRIPTION

[0019] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0020] like Figures 1 to 6 As shown, the process of extracting electronic grade isopropanol from industrial isopropanol of the present invention comprises the following steps: S1: performing multi-stage pre-filtration treatment on the raw material isopropyl alcohol to remove large particle impurities in the raw material isopropyl alcohol, and then performing light fractionation and heavy fractionation on the raw material isopropyl alcohol to remove light components and heavy components contained in the raw material isopropyl alcohol to obtain a secondary raw material; S2: The secondary raw material is input into the dehydration adsorption device for processing, and the water contained in the material is removed to obtain the tertiary raw material: the material is first sent into the dehydration tower 3, and the vaporized material distilled from the dehydration tower 3 is directly sent into the auxiliary dehydrator 4, and the remaining water in the material is removed by the permeation vaporization membrane; wherein, a detector and a temporary storage tank are arranged behind the auxiliary dehydrator 4: the tertiary raw material that fails the moisture content test is stored in the temporary storage tank, and then the material in the temporary storage tank is input into the dehydration tower 3 for circulation, and the tertiary raw material that passes the moisture content test is directly transported from the temporary storage tank to the subsequent processing equipment; S3: Inputting the tertiary raw material into the ion tank 5 to remove the metal ions contained therein to obtain the quaternary raw material; S4: Inputting the quaternary raw material into the filtering and separation device 6 to remove the impurity particles therein to obtain an electronic grade isopropyl alcohol product; Wherein, in the step S1, the components with lower and higher boiling points than isopropanol are light components and heavy components respectively; in the step S1, the raw material isopropanol is de-lightened and de-heaved by a multi-stage distillation tower; the ion tank 5 and the filtering and separating device 6 in the steps S3 and S4 are multi-stage series-arranged; the ion tank 5 is filled with ion exchange resin; The water absorption and desorption device comprises a dehydration tower 3 and an auxiliary dehydrator 4, and the product outlet on the dehydration tower 3 is connected to the auxiliary dehydrator 4; An upper isolation plate 433 and a lower isolation plate 422 are installed in the auxiliary dehydrator 4 from top to bottom. The upper isolation plate 433 and the lower isolation plate 422 divide the space in the auxiliary dehydrator 4 into a separation chamber 41, a heat exchange chamber 43 and an extension chamber from top to bottom. A heat preservation layer is installed outside the auxiliary dehydrator 4. The separation chamber 41 is provided with a feed port 411 and a discharge port 413, the heat exchange chamber 43 is provided with an input port 431 and an output port 432, and the seepage chamber 42 is provided with a seepage liquid port 421; A fixing plate 414 is installed in the separation chamber 41, a seepage vaporization membrane tube 44 is installed between the fixing plate 414 and the lower isolation plate 422, a heat pipe 46 is installed in the seepage vaporization membrane tube 44, the upper end of the heat pipe 46 passes through the upper isolation plate 433 and is located in the heat exchange chamber 43, the heat pipe 46 is fixed by the upper isolation plate 433, the space between the fixing plate 414 and the upper isolation plate 433 is an air extraction chamber, an air extraction port 412 is installed in the air extraction chamber, the air extraction chamber and the seepage chamber 42 are connected to each other through the seepage vaporization membrane tube 44, and a retaining ring 464 is installed on the part of the heat pipe 46 located in the air extraction chamber; During operation, the raw material isopropyl alcohol is sequentially fed into the light-removal tower 1 and the heavy-removal tower 2, so that the light components and heavy components in the raw material are fully removed, such as acetone, water, and some metal ions. After that, the material after light-removal and heavy-removal is fed into the adsorption dehydration device for dehydration. After dehydration, the material is sequentially fed into the ion tank 5 and the filtration separation device 6 to remove the remaining trace metal ions and particulate impurities in the material as much as possible, so as to ensure that the electronic grade isopropyl alcohol product with good quality is obtained; wherein, the unspecified parts in this process are implemented by the technical methods known in the prior art; In the dehydration process, the material transported by the deweighting tower 2 first enters the dehydration tower 3, where it is dehydrated to remove most of the remaining water in the material. After that, the material distilled from the dehydration tower 3 is input into the auxiliary dehydrator 4 from the feed port 411 to be further fully dehydrated to remove the remaining water in the material as much as possible. After that, the material discharged from the discharge port 413 subsequently enters the ion tank 5 and the filtering and separation device 6. At the same time, the pipeline between the dehydration tower 3 and the feed port 411 adopts an insulated pipeline, and the auxiliary dehydrator 4 is arranged at a position close to the dehydration tower 3, so as to ensure that the insulated pipeline between the dehydration tower 3 and the feed port 411 is short and the temperature of the material transported in the pipeline does not drop too much, so that the material entering the separation chamber 41 on the auxiliary dehydrator 4 is in a vaporized state, making full use of heat and improving the working efficiency of the equipment; wherein, as another embodiment, according to actual conditions, an evaporator is arranged at the auxiliary dehydrator 4 to further heat the material, so as to ensure that the raw material is in a vaporized state when entering the separation chamber 41; At the same time, after the material enters the auxiliary dehydrator 4, the material is located in the separation chamber 41, and the external vacuum pump evacuates air from the air extraction port 412, so that the pressure in the air extraction chamber, the inside of the seepage vaporization membrane tube 44 and the seepage chamber 42 is reduced, so that the water in the material seeps and separates into the inside of the seepage vaporization membrane tube 44, and then the water enters the seepage chamber 42 and is discharged from the seepage liquid port 421, thereby completing the removal of water from the material and ensuring that the water content of the material is low after treatment; At the same time, the raw material isopropanol with a relatively low temperature enters the heat exchange chamber 43 from the input port 431, and the raw material isopropanol with a higher temperature after heat exchange leaves from the output port 432 and is sent to the entrance of the light removal tower 1, thereby improving the utilization of heat in the production process and reducing energy consumption. At the same time, since the upper end of the heat pipe 46 is located in the heat exchange chamber 43 and the lower end of the heat pipe 46 is located in the seepage vaporization membrane tube 44, the heat contained in the water entering the seepage vaporization membrane tube 44 and contacting the surface of the heat pipe 46 will be transferred to the heat exchange chamber 43, thereby promoting the rapid condensation and liquefaction of the water in the seepage vaporization membrane tube 44, reducing the component partial pressure of the water in the seepage vaporization membrane tube 44, and promoting the water contained in the material in the separation chamber 41 to pass through the seepage vaporization membrane tube 44 to be separated and collected, thereby improving the efficiency and effect of removing water from the material; At the same time, after the moisture in the seepage vaporization membrane tube 44 condenses and liquefies on the surface of the heat pipe 46, it will slide downward under the action of gravity and enter the seepage cavity 42, and finally be discharged from the seepage liquid port 421 in the seepage cavity 42. In this process, the moisture discharged from the air extraction port 412 is relatively reduced, thereby reducing the moisture content in the gas entering the vacuum pump pipeline system, and reducing the possibility of vacuum pump failure caused by excessive moisture content. At the same time, the retaining ring 464 on the heat pipe 46 is close to the opening of the seepage vaporization membrane tube 44 in the air extraction cavity, so that the retaining ring 464 blocks the tiny droplets on the surface of the heat pipe 46 driven by the airflow, reducing the possibility of the droplets flying off the surface of the heat pipe 46 driven by the airflow and leaving the air extraction cavity from the air extraction port 412; at the same time, the liquid discharged from the seepage liquid port 421 can also be conveniently collected and processed, avoiding the difficulty of collecting and processing the moisture after it is sucked into the pipeline system of the vacuum pump along with the air.

[0021] As an embodiment of the present invention, a limiting frame 462 is installed in the seepage vaporization membrane tube 44, and the limiting frame 462 clamps and fixes the heat pipe 46; The surfaces of the heat pipe 46 and the limiting frame 462 are provided with a hydrophobic coating; Since the length of the seepage vaporization membrane tube 44 is relatively long and the diameter of the heat pipe 46 is relatively thin, the heat pipe 46 inside the auxiliary dehydrator 4 is prone to swing and vibrate during operation, resulting in contact or collision between the heat pipe 46 and the inner wall of the seepage vaporization membrane tube 44, affecting the normal use of the seepage vaporization membrane tube 44. The contact between the heat pipe 46 and the seepage vaporization membrane tube 44 is likely to cause the temperature of the seepage vaporization tube surface to decrease, making the vaporized material in the separation chamber 41 easily cooled and liquefied in advance, affecting the dehydration separation effect. At the same time, a limit frame 462 is installed inside the seepage vaporization membrane tube 44, and the limit frame 462 is used to clamp and fix the heat pipe 46 to ensure that the position of the heat pipe 46 inside the seepage vaporization membrane tube 44 is stable, thereby preventing the heat pipe 46 from swinging and vibrating, which would affect the normal use and service life of the heat pipe 46 and the seepage vaporization membrane tube 44.

[0022] As an embodiment of the present invention, a groove 461 is provided on the surface of the heat pipe 46, and a protrusion is provided on the limiting frame 462, and the protrusion and the groove 461 cooperate with each other; The limit frame 462 is provided with a deformation sheet 463 , and the deformation sheet 463 is a bimetallic sheet; The protrusion on the limit frame 462 and the groove 461 on the heat pipe 46 cooperate with each other to stabilize the position of the heat pipe 46 in the seepage vaporization membrane tube 44, and prevent the limit frame 462 from being skewed or offset under the influence of external vibration or external force, so that the position of the limit frame 462 is unstable and affects the normal use of the auxiliary dehydrator 4; At the same time, since a deformation piece 463 made of a bimetallic sheet is installed on the limit frame 462, during the dehydration process, the temperature inside the seepage vaporization membrane tube 44 increases, so that the deformation piece 463 on the limit frame 462 is deformed by the heat, so that the limit frame 462 becomes an interference fit between the heat pipe 46 and the inner wall of the seepage vaporization membrane tube 44, further improving the stability of the limit frame 462 and ensuring the stable position of the heat pipe 46.

[0023] As an embodiment of the present invention, a vibration plate 45 is installed in the separation chamber 41, and a connecting rod 451 is installed on the vibration plate 45, and two ends of the connecting rod 451 are respectively connected to the fixed plate 414 and the lower isolation plate 422; The vibration plate 45 is provided in multiple groups in the separation chamber 41, and each group of the vibration plate 45 is composed of multiple units from top to bottom, and the vibration plate 45 is located near the seepage vaporization membrane tube 44; Since multiple sets of vibration plates 45 are installed in the separation chamber 41 and the vibration plates 45 are located near the seepage vaporization membrane tube 44, when the material enters the separation chamber 41, the material will be blocked and disturbed by the vibration plates 45, so that the material is evenly distributed in the separation chamber 41, and the time the material stays in the separation chamber 41 is extended, thereby improving the efficiency and effect of material dehydration; At the same time, after the material impacts the vibration plate 45, the vibration plate 45 will move, so that the material near the vibration plate 45 is stirred. In addition, since the vibration plate 45 is located near the seepage vaporization membrane tube 44, after the material is stirred by the vibration plate 45, it will further make the material evenly distributed near the seepage vaporization membrane tube 44, thereby effectively reducing the possibility of concentration polarization near the seepage vaporization membrane tube 44, preventing the osmotic membrane from being blocked, and ensuring that the dehydration effect and efficiency of the auxiliary dehydrator 4 are good.

[0024] As an embodiment of the present invention, the connecting rod 451 is located near the middle of the vibration plate 45, and the installation positions of the connecting rods 451 on each group of the vibration plate 45 are different; Since the installation positions of the connecting rods 451 on each group of vibration plates 45 are different, the vibration amplitudes and frequencies of each group of vibration plates 45 when vibrating under impact are different, which will fully disturb the material in the separation chamber 41, promote uniform distribution of the material, avoid concentration polarization, and ensure the removal of water from the material. At the same time, since the vibration amplitudes and frequencies between each group of vibration plates 45 are different, resonance between the vibration plates 45 can also be avoided, thereby ensuring the safety of the operation of the auxiliary dehydrator 4.

[0025] As an embodiment of the present invention, an elastic sleeve 452 is installed on the connecting rod 451, and the vibration plate 45 on the connecting rod 451 is fixed by the elastic sleeve 452, and the vibration plate 45 is slidably installed on the connecting rod 451; Since the vibration plate 45 is slidably installed on the connecting rod 451, when the vibration plate 45 is impacted by the material and affected by external vibration, the vibration plate 45 will slide up and down on the connecting rod, thereby expanding the range of the vibration plate 45 stirring the material, prompting the material to be evenly distributed near the seepage vaporization membrane tube 44, avoiding concentration polarization, and ensuring the smooth dehydration of the material. At the same time, since the elastic sleeve 452 is installed on the connecting rod 451, and the elastic sleeve 452 is located between adjacent vibration plates 45, the vibration plate 45 will be evenly distributed on the connecting rod 451 under the elastic action of the elastic sleeve 452, and there will be mutual correlation between the vibration plates 45 on the connecting rod 451, and then after the vibration plate 45 slides up and down, it will drive the entire group of vibration plates 45 installed on the connecting rod 451 to move, fully expanding the stirring effect of the vibration plate 45 on the material, so that the material near the seepage vaporization membrane tube 44 is stirred, prompting the material to be evenly distributed, and promoting the removal of water in the material.

[0026] As an embodiment of the present invention, the vibration plate 45 is provided with evenly distributed through holes 453; Since the through hole 453 is provided on the vibration plate 45, the material in the separation chamber 41 passes through the through hole 453 during the up and down movement and vibration of the vibration plate 45, causing a turbulent flow of the material, thereby increasing the dispersion and uniformity of the material, and preventing the material from flowing too orderly, causing concentration polarization near the pervaporation membrane tube, and affecting the effect of removing water from the material; At the same time, the through hole 453 is opened to relatively reduce the interaction area between the vibration plate 45 and the material during vibration and up and down movement, thereby reducing the resistance to the interaction between the vibration plate 45 and the material during movement, facilitating the vibration and up and down movement of the vibration plate 45, improving the disturbance effect on the material near the seepage vaporization membrane tube 44, making the material evenly distributed, and promoting the removal of moisture in the material.

[0027] As an embodiment of the present invention, an elastic thread is installed on the side of the vibration plate 45, and the elastic thread contacts the surface of the seepage vaporization membrane tube 44; Since the vibration plate 45 is located near the permeation vaporization membrane tube 44, when the vibration plate 45 vibrates and moves up and down, the elastic wire on the vibration plate 45 will sweep the surface of the permeation vaporization membrane tube 44, thereby simply cleaning the surface of the permeation vaporization membrane tube 44, removing impurities attached to the surface of the permeation vaporization membrane tube 44 during the material dehydration process, and reducing the possibility of blockage of the permeation vaporization membrane tube, thereby ensuring the normal use of the auxiliary dehydrator 4.

[0028] The specific workflow is as follows: During operation, the raw material isopropanol is sequentially fed into the light-removal tower 1 and the heavy-removal tower 2 to fully remove the light components and heavy components in the raw material. After that, the material after light-removal and heavy-removal is fed into the adsorption dehydration device for dehydration. After dehydration, the material is sequentially fed into the ion tank 5 and the filtering and separation device 6 to remove the remaining trace metal ions and particulate impurities in the material. Among them, the unspecified parts in this process are implemented by the technical methods known in the prior art. In the dehydration process, the material transported by the deweighting tower 2 first enters the dehydration tower 3, and is dehydrated in the dehydration tower 3. After that, the material distilled from the dehydration tower 3 is input into the auxiliary dehydrator 4 from the feed port 411 for further dehydration. After that, the material discharged from the discharge port 413 enters the ion tank 5 and the filtering and separation device 6. At the same time, the pipeline between the dehydration tower 3 and the feed port 411 adopts an insulated pipeline, and the auxiliary dehydrator 4 is arranged at a position close to the dehydration tower 3, so that the material entering the separation chamber 41 of the auxiliary dehydrator 4 is in a vaporized state; wherein, as another embodiment, according to actual conditions, an evaporator is arranged at the auxiliary dehydrator 4 to further heat the material; At the same time, after the material enters the auxiliary dehydrator 4, the material is located in the separation chamber 41, and the external vacuum pump extracts air from the air extraction port 412, so that the pressure in the air extraction chamber, the inside of the seepage vaporization membrane tube 44 and the seepage chamber 42 is reduced, so that the water in the material seeps and separates into the inside of the seepage vaporization membrane tube 44, and then the water enters the seepage chamber 42 and is discharged from the seepage liquid port 421; At the same time, the raw material isopropanol with a relatively low temperature enters the heat exchange chamber 43 from the input port 431, and the raw material isopropanol with a higher temperature after heat exchange leaves from the output port 432 and is sent to the entrance of the light removal tower 1. At the same time, the heat pipe 46 transfers the heat contained in the water that enters the seepage vaporization membrane tube 44 and contacts the surface of the heat pipe 46 to the heat exchange chamber 43, and the water in the seepage vaporization membrane tube 44 is quickly condensed and liquefied, reducing the component partial pressure of the water in the seepage vaporization membrane tube 44, and promoting the water contained in the material in the separation chamber 41 to pass through the seepage vaporization membrane tube 44 to be separated and collected; At the same time, after the water in the seepage vaporization membrane tube 44 condenses and liquefies on the surface of the heat pipe 46, it will slide downward under the action of gravity and enter the seepage cavity 42, and finally be discharged from the seepage liquid port 421 in the seepage cavity 42. In this process, the water discharged from the air extraction port 412 is relatively reduced, thereby reducing the water content in the gas entering the vacuum pump pipeline system. At the same time, the baffle ring 464 on the heat pipe 46 is close to the opening of the seepage vaporization membrane tube 44 in the air extraction cavity, and the baffle ring 464 is used to block the tiny droplets on the surface of the heat pipe 46 driven by the air flow, thereby reducing the possibility that the droplets fly off the surface of the heat pipe 46 driven by the air flow and leave the air extraction cavity from the air extraction port 412. A limiting frame 462 is installed inside the seepage vaporization membrane tube 44, and the limiting frame 462 is used to clamp and fix the heat pipe 46 to ensure that the position of the heat pipe 46 inside the seepage vaporization membrane tube 44 is stable; The cooperation between the protrusion on the limiting frame 462 and the groove 461 on the heat pipe 46 ensures that the heat pipe 46 is positioned stably in the permeation vaporization membrane tube 44, and prevents the limiting frame 462 from being skewed or offset due to external vibration or external force. At the same time, since the deformation piece 463 made of bimetallic sheet is installed on the limiting frame 462, during the dehydration process, the temperature inside the seepage vaporization membrane tube 44 rises, causing the deformation piece 463 on the limiting frame 462 to be deformed by the heat, so that the limiting frame 462 becomes an interference fit between the heat pipe 46 and the inner wall of the seepage vaporization membrane tube 44; When the material enters the separation chamber 41, the material will be blocked and disturbed by the vibration plate 45, so that the material is evenly distributed in the separation chamber 41 and the time the material stays in the separation chamber 41 is prolonged; At the same time, after the material impacts the vibration plate 45, the vibration plate 45 will move, so that the material near the vibration plate 45 is stirred. In addition, since the vibration plate 45 is located near the seepage vaporization membrane tube 44, after the material is stirred by the vibration plate 45, the material will be further evenly distributed near the seepage vaporization membrane tube 44, reducing the possibility of concentration polarization near the seepage vaporization membrane tube 44. Since the installation positions of the connecting rods 451 on the vibration plates 45 of each group are different, the vibration amplitudes and frequencies of the vibration plates 45 of each group are different when they are impacted and vibrate, which will fully disturb the materials in the separation chamber 41 and promote uniform distribution of the materials. At the same time, since the vibration amplitudes and frequencies of the vibration plates 45 of each group are different, resonance between the vibration plates 45 can also be avoided. Since the vibration plate 45 is slidably installed on the connecting rod 451, when the vibration plate 45 is impacted by the material and the influence of external vibration, the vibration plate 45 will slide up and down on the connecting rod, thereby expanding the range of the vibration plate 45 stirring the material. At the same time, since the elastic sleeve 452 is installed on the connecting rod 451, and the elastic sleeve 452 is located between adjacent vibration plates 45, the vibration plate 45 will be evenly distributed on the connecting rod 451 under the elastic action of the elastic sleeve 452, and there will be mutual correlation between the vibration plates 45 on the connecting rod 451, so that after the vibration plate 45 slides up and down, it will drive the whole group of vibration plates 45 installed on the connecting rod 451 to move, fully expanding the stirring effect of the vibration plate 45 on the material; Since the through hole 453 is provided on the vibration plate 45, during the up and down movement and vibration of the vibration plate 45, the material in the separation chamber 41 passes through the through hole 453, causing a turbulent flow of the material; At the same time, the through hole 453 is provided to relatively reduce the interaction area between the vibration plate 45 and the material during vibration and up and down movement, so that the resistance of the interaction between the vibration plate 45 and the material during the movement is reduced, which facilitates the vibration and up and down movement of the vibration plate 45. Since the vibration plate 45 is located near the seepage vaporization membrane tube 44, when the vibration plate 45 vibrates and moves up and down, the elastic wire on the vibration plate 45 will sweep the surface of the seepage vaporization membrane tube 44, thereby simply cleaning the surface of the seepage vaporization membrane tube 44 and removing impurities attached to the surface of the seepage vaporization membrane tube 44 during the material dehydration process.

[0029] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A process for extracting electronic grade isopropanol from industrial isopropanol, characterized in that: The process comprises the following steps: S1: performing multi-stage pre-filtration treatment on the raw material isopropyl alcohol to remove large particle impurities in the raw material isopropyl alcohol, and then performing light fractionation and heavy fractionation on the raw material isopropyl alcohol to remove light components and heavy components contained in the raw material isopropyl alcohol to obtain a secondary raw material; S2: The secondary raw material is input into a dehydration adsorption device for treatment to remove the water contained in the material to obtain a tertiary raw material: the material is first fed into a dehydration tower (3), and the vaporized material distilled from the dehydration tower (3) is directly fed into an auxiliary dehydrator (4), and the remaining water in the material is removed by a permeation vaporization membrane; wherein a detector and a temporary storage tank are arranged behind the auxiliary dehydrator (4): the tertiary raw material that fails the moisture content test is stored in a temporary storage tank, and then the material in the temporary storage tank is input into the dehydration tower (3) for circulation, and the tertiary raw material that passes the moisture content test is directly transported from the temporary storage tank to subsequent processing equipment; S3: Inputting the tertiary raw material into an ion tank (5) to remove the metal ions contained therein to obtain a quaternary raw material; S4: feeding the quaternary raw material into a filtering and separation device (6) to remove impurity particles therein, thereby obtaining an electronic grade isopropyl alcohol product; wherein, in step S1, the components with lower and higher boiling points than isopropanol are light components and heavy components, respectively; in step S1, the raw material isopropanol is de-lightened and de-heaved by a multi-stage distillation tower; the ion tank (5) and the filtering and separation equipment (6) in steps S3 and S4 are multi-stage series-connected; the ion tank (5) is filled with ion exchange resin; The water absorption and desorption device comprises a dehydration tower (3) and an auxiliary dehydrator (4), and the product outlet on the dehydration tower (3) is connected to the auxiliary dehydrator (4); An upper isolation plate (433) and a lower isolation plate (422) are installed in the auxiliary dehydrator (4) from top to bottom, and the upper isolation plate (433) and the lower isolation plate (422) divide the space in the auxiliary dehydrator (4) from top to bottom into a separation chamber (41), a heat exchange chamber (43) and an extension chamber, and a heat insulation layer is installed outside the auxiliary dehydrator (4); The separation chamber (41) is provided with a feed port (411) and a discharge port (413), the heat exchange chamber (43) is provided with an input port (431) and an output port (432), and the seepage chamber (42) is provided with a seepage liquid port (421); A fixed plate (414) is installed in the separation chamber (41), and a seepage vaporization membrane tube (44) is installed between the fixed plate (414) and the lower isolation plate (422). A heat pipe (46) is installed in the seepage vaporization membrane tube (44). The upper end of the heat pipe (46) passes through the upper isolation plate (433) and is located in the heat exchange chamber (43). The heat pipe (46) is fixed by the upper isolation plate (433). The space between the fixed plate (414) and the upper isolation plate (433) is an air extraction chamber. An air extraction port (412) is installed in the air extraction chamber. The air extraction chamber and the seepage chamber (42) are interconnected through the seepage vaporization membrane tube (44). A retaining ring (464) is installed on the part of the heat pipe (46) located in the air extraction chamber.

2. A process for extracting electronic grade isopropanol from industrial isopropanol according to claim 1, characterized in that: A limiting frame (462) is installed in the seepage vaporization membrane tube (44), and the limiting frame (462) clamps and fixes the heat pipe (46); The surfaces of the heat pipe (46) and the limiting frame (462) are provided with a hydrophobic coating.

3. A process for extracting electronic grade isopropanol from industrial isopropanol according to claim 2, characterized in that: A groove (461) is provided on the surface of the heat pipe (46), and a protrusion is provided on the limiting frame (462), and the protrusion and the groove (461) cooperate with each other; A deformation sheet (463) is installed on the limiting frame (462), and the deformation sheet (463) is a bimetallic sheet.

4. A process for extracting electronic grade isopropanol from industrial isopropanol according to claim 1, characterized in that: A vibration plate (45) is installed in the separation chamber (41), a connecting rod (451) is installed on the vibration plate (45), and two ends of the connecting rod (451) are respectively connected to the fixed plate (414) and the lower isolation plate (422); The vibration plates (45) are arranged in a plurality of groups in the separation chamber (41), each group of the vibration plates (45) is composed of a plurality of units from top to bottom, and the vibration plates (45) are located close to the seepage vaporization membrane tube (44).

5. A process for extracting electronic grade isopropanol from industrial isopropanol according to claim 4, characterized in that: The connecting rod (451) is located near the middle of the vibration plate (45), and the installation positions of the connecting rods (451) on each group of the vibration plate (45) are different.

6. A process for extracting electronic grade isopropyl alcohol from industrial isopropyl alcohol according to claim 4, characterized in that: An elastic sleeve (452) is installed on the connecting rod (451), and the vibration plates (45) on the connecting rod (451) are fixed by the elastic sleeve (452), and the vibration plates (45) are slidably installed on the connecting rod (451).

7. A process for extracting electronic grade isopropyl alcohol from industrial isopropyl alcohol according to claim 4, characterized in that: The vibration sheet plate (45) is provided with evenly distributed through holes (453).

8. A process for extracting electronic grade isopropyl alcohol from industrial isopropyl alcohol according to claim 4, characterized in that: An elastic thread is installed on the side surface of the vibration sheet (45), and the elastic thread contacts the surface of the seepage vaporization membrane tube (44).

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