An ultra-high purity methanol production device and method

Abstract

The present invention discloses a production device and method for ultra-high-purity methanol, comprising a heater, a distillation device, a first filter membrane, a second filter membrane, and a third filter membrane, wherein the first inlet of the first filter membrane is connected to the first outlet of the heater, and the first retentate side of the first filter membrane is connected to the first inlet of the distillation device; the second inlet of the second filter membrane is connected to the top outlet of the distillation device, and the second retentate side of the second filter membrane is connected to the first inlet of the distillation device; the second permeate side of the second filter membrane is connected to the third inlet of the third filter membrane, and the retentate side of the third filter membrane is connected to the second inlet of the second filter membrane. The present invention can further improve low-purity methanol or high-purity methanol to ultra-high-purity methanol, and the product purity of ultra-high-purity methanol is high.

Description

Technical Field

[0001] The present invention relates to the technical field of ultra-clean high-purity chemical reagents, and in particular to a production device and method for ultra-high-purity methanol. Background Art

[0002] Ultra-clean, high-purity reagents, also known as wet chemicals or process chemicals, are key chemicals in the manufacturing of large-scale or ultra-large-scale integrated circuits and high-end semiconductor devices. They are primarily used in processes such as cleaning, photolithography, and etching of silicon single wafers. Their purity and cleanliness have a crucial impact on the yield, electrical performance, and reliability of integrated circuits. For megabit devices, particles as small as 0.10μm can cause device failure. Submicron devices (4.0-35.0μm) require fewer than 10 particles of 0.1μm. Furthermore, various metal impurities, such as Fe, Cu, Cr, Ni, Al, and Na, must be controlled below the detection limit of current analytical techniques (approximately 1×1010 atoms / cm2). At present, the international SEMI standardization organization divides ultra-clean and high-purity reagents into four levels according to their application scope: SEMI-C1 standard (applicable to the production of IC process technology >4.2μm), SEMI-C7 standard (applicable to the production of IC process technology 0.8~4.2μm), SEMI-C8 standard (applicable to the production of IC process technology 0.09~0.20μm), and SEMI-C12 standard (applicable to the production of IC process technology 0.09~0.20μm).

[0003] Using existing ultra-high purity methanol production and preparation equipment and methods, the high-purity methanol finally extracted still contains a certain amount of organic impurities and metal ions, resulting in a relatively low purity of the finally extracted methanol. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention provides a device and method for producing ultra-high purity methanol, which can further improve the product purity of ultra-high purity methanol.

[0005] The present invention is achieved through the following technical solutions:

[0006] A production device for ultra-high-purity methanol includes a heater, a distillation device, a first filter membrane, a second filter membrane and a third filter membrane, wherein the first inlet of the first filter membrane is connected to the first discharge outlet of the heater, and the first retentate side of the first filter membrane is connected to the first inlet of the distillation device; the second inlet of the second filter membrane is connected to the top outlet of the distillation device, and the second retentate side of the second filter membrane is connected to the first inlet of the distillation device; the second permeate side of the second filter membrane is connected to the third inlet of the third filter membrane, and the third retentate side of the third filter membrane is connected to the second inlet of the second filter membrane.

[0007] Furthermore, the distillation device includes a light removal tower and a heavy removal tower, the bottom outlet of the light removal tower is connected to the second inlet of the heavy removal tower, the first inlet is provided on the light removal tower, and the top outlet is provided on the heavy removal tower.

[0008] Furthermore, the production device further includes a first condensing device, and the second inlet of the first condensing device is connected to the first permeation side of the first filter membrane.

[0009] Furthermore, the production device also includes a second condensation device arranged between the second filter membrane and the third filter membrane, the third inlet of the second condensation device is connected to the second permeation side of the second filter membrane, and the third outlet of the second condensation device is connected to the third inlet of the third filter membrane.

[0010] Furthermore, the first filter membrane is an organic composite membrane, an inorganic composite membrane, or an organic-inorganic composite water-permeable membrane, and is used to filter water in methanol.

[0011] Furthermore, the second filter membrane is an organic composite membrane, the support layer of the second filter membrane is polytetrafluoroethylene, and the separation layer is a fluorine-containing polymer.

[0012] Furthermore, the third filter membrane is an organic composite membrane, the support layer of the third filter membrane is polytetrafluoroethylene, and the separation layer is a fluorocarbon polymer chelate membrane.

[0013] Furthermore, the preparation method of the fluorocarbon polymer chelate membrane is as follows:

[0014] The porous PTFE membrane is subjected to hydrophilic treatment to obtain a hydrophilic base membrane;

[0015] The chelating resin is washed with hydrochloric acid solution, sodium hydroxide solution and deionized water in sequence and then dried;

[0016] Grinding and sieving the cleaned and dried chelating resin to obtain powder;

[0017] The powder is mixed with polyisobutylene and polyhexafluoroethylene emulsion, and vacuum degassing is performed to form a coating liquid;

[0018] The coating liquid is applied on a hydrophilic base film to form a chelating film;

[0019] The prepared chelating membrane is washed with hydrochloric acid solution, sodium hydroxide solution and pure water in sequence until it becomes neutral, and then dried for storage.

[0020] A method for producing ultra-high purity methanol comprises the following steps:

[0021] Heating treatment of low-purity methanol;

[0022] Remove water content from low-purity methanol;

[0023] Remove organic impurities and most metal ions from low-purity methanol;

[0024] Further remove metal ions and particulate matter from low-purity methanol;

[0025] Cooling of low-purity methanol;

[0026] Metal ions and particulate matter are removed again from low-purity methanol.

[0027] Furthermore, the step of removing organic impurities and most metal ions in low-purity methanol specifically includes:

[0028] Removal of lighter organic impurities from low-purity methanol;

[0029] Remove most metal ions and organic impurities with higher boiling points than methanol in low-purity methanol.

[0030] Compared with the prior art, the advantages of the present invention are:

[0031] 1. The present invention first uses a pervaporation water-permeable membrane to remove the water content in methanol. Compared with the dehydration treatment in a distillation tower, the energy consumption is reduced by more than 50% and the product yield is high.

[0032] 2. The present invention removes most of the metal ions and organic impurities that are lighter than methanol and have a higher boiling point than methanol through light and heavy removal distillation towers.

[0033] 3. The present invention uses a second filter membrane to remove metal ions through an electronic-grade pervaporation membrane that preferentially permeates methanol. Compared with traditional multi-effect distillation tower treatment, energy consumption is reduced by more than 90%. The second filter membrane is a dense membrane that can also remove particulate matter, thereby improving the product purity of ultra-high-purity methanol.

[0034] 4. The present invention removes trace metal ions by preparing an electronic-grade fluorocarbon polymer chelate membrane reaction. The retentate side of the third filter membrane is returned to the second filter membrane. The reaction removal effect is good and the product yield can be improved. The membrane pore size is relatively small, and particulate matter can be removed at the same time, thereby improving the product purity of ultra-high purity methanol. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic structural diagram of an ultra-high purity methanol production device according to one embodiment of the present invention;

[0036] Figure 2 The present invention is a flow chart of a method for producing ultra-high purity methanol.

[0037] 1. Heater; 10. First inlet; 11. First outlet; 2. Rectification unit; 20. Light-removal column; 200. First distillation column; 201. First condensing column; 202. First reboiler; 203. First inlet; 204. Bottom outlet; 21. Heavy-removal column; 210. Second distillation column; 211. Second condensing column; 212. Second reboiler; 213. Second inlet; 214. Top outlet; 3. First filter membrane; 30. First inlet; 31. First retentate side; 32 , first permeate side; 4, second filter membrane; 40, second inlet; 41, second retentate side; 42, second permeate side; 5, third filter membrane; 50, third inlet; 51, third retentate side; 52, third permeate side; 7, first condensation device; 70, first condenser; 700, second inlet; 701; second outlet; 71, first vacuum pump; 8, second condensation device; 80, second condenser; 800, third inlet; 801, third outlet; 81, second vacuum pump. DETAILED DESCRIPTION

[0038] The following is a further non-restrictive detailed description of the technical solution of the invention in conjunction with the preferred embodiments and the accompanying drawings. In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and cannot be understood as limiting the present invention.

[0039] like Figure 1 As shown, an ultra-high purity methanol production device according to one embodiment of the present invention includes a heater 1, a distillation device 2, a first filter membrane 3, a second filter membrane 4, a third filter membrane 5, a first condensing device 7 and a second condensing device 8. First filtrationThe first inlet 30 of membrane 3 is connected to the first outlet 11 of heater 1. The first retentate side 31 of first filter membrane 3 is connected to the first inlet 203 of distillation unit 2. The first permeate side 32 of first filter membrane 3 is connected to the second inlet 700 of first condenser 7. The second outlet 701 of first condenser 7 is used to discharge condensed wastewater. The second inlet 40 of second filter membrane 4 is connected to the top outlet 214 of distillation unit 2. The second retentate side 41 of second filter membrane 4 is connected to the first inlet 203 of distillation unit 2. The second permeate side 42 of second filter membrane 4 is connected to the third inlet 50 of third filter membrane 5. Second condenser 8 is disposed between second filter membrane 4 and third filter membrane 5. Specifically, the third inlet 800 of second condenser 8 is connected to the second permeate side 42 of second filter membrane 4. The third outlet 801 of second condenser 8 is connected to the third inlet 50 of third filter membrane 5. The third retentate side 51 of third filter membrane 5 is connected to the second inlet 40 of second filter membrane 4. The third permeate side 52 of third filter membrane 5 is the final product.

[0040] The distillation device 2 includes a light removal column 20 and a heavy removal column 21. The bottom outlet 204 of the light removal column 20 is connected to the second inlet 213 of the heavy removal column 21. The first inlet 203 is provided on the light removal column 20, and the top outlet 214 is provided on the heavy removal column 21. By providing the distillation device 2, the distillation device 2 removes organic impurities that are lighter than methanol and have a higher boiling point than methanol, as well as most metal ions.

[0041] The light-removal tower 20 includes a first distillation tower 200 , a first condensing tower 201 and a first reboiler 202 . The first condensing tower 201 is arranged at the top of the first distillation tower 200 , and the first reboiler 202 is arranged at the bottom of the first distillation tower 200 .

[0042] The de-weighting tower 21 includes a second distillation tower 210, a second condensing tower 211, and a second reboiler 212. The second condensing tower 211 is arranged at the top of the second distillation tower 210, and the second reboiler 212 is arranged at the bottom of the second distillation tower 210. The first inlet 203 of the first distillation tower 200 is connected to the first retentate side 31 of the first filter membrane 3, the bottom outlet 204 of the first distillation tower 200 is connected to the second inlet 213 of the second distillation tower 210, and the top outlet 214 of the second distillation tower 210 is connected to the second inlet 40 of the second filter membrane 4. The de-weighting tower 21 and the de-lighting tower 20 remove organic impurities lighter than methanol and with a higher boiling point than methanol, and most metal ions.

[0043] The first condensing device 7 includes a first condenser 70 and a first vacuum pump 71. The first condenser 70 and the first vacuum pump 71 are connected. The second inlet 700 of the first condenser 70 is connected to the first permeate side 32 of the first filter membrane 3. The second outlet 701 of the first condenser 70 is used to discharge the condensed wastewater. The first vacuum pump 71 extracts air from the first condenser 70 to prevent nitrogen, oxygen, and other non-condensable gases in the air from causing a pressure increase in the first condenser 70.

[0044] The second condensing device 8 includes a second condenser 80 and a second vacuum pump 81. The second condenser 80 and the second vacuum pump 81 are connected. The third inlet 800 of the second condenser 80 is connected to the second permeate side 42 of the second filter membrane 4. The third outlet 81 of the second condenser 80 is connected to the third inlet 50 of the third filter membrane 5. The function of the second vacuum pump 81 is similar to that of the first vacuum pump 71 and will not be further described here.

[0045] In this embodiment, the first filter membrane 3 is an organic composite membrane, an inorganic composite membrane, or an organic-inorganic composite membrane, and is used to filter water from methanol. The organic composite membrane can be made of PVA / PVDF / PET, and the inorganic composite membrane can be made of a molecular sieve membrane / ceramic composite membrane. The organic-inorganic composite membrane is a composite membrane that combines organic and inorganic membrane technologies, such as an organic-inorganic composite hydrophobic membrane. This is prior art and will not be described in detail here. The present invention first uses a pervaporation permeable membrane to remove water from methanol. Compared to dehydration treatment in a distillation tower, this reduces energy consumption by over 50% and achieves a high product yield.

[0046] The second filter membrane 4 is an organic composite membrane with a support layer of polytetrafluoroethylene and a separation layer of a fluoropolymer. It has a preferential selectivity for methanol, and the components that permeate the membrane remain in the vapor phase, effectively retaining metal ions. The second filter membrane 4 removes metal ions through an electronic-grade pervaporation membrane that preferentially permeates methanol, reducing energy consumption by over 90% compared to traditional multi-effect distillation towers. The second filter membrane 4 is a dense membrane that also removes particulate matter.

[0047] The third filter membrane 5 is an organic composite membrane, with a polytetrafluoroethylene support layer and a fluorocarbon polymer chelate membrane as the separation layer. The chelate membrane contains atoms with unbonded lone pairs of electrons, which form coordination bonds with metal ions, thereby removing metal ions. The electronic-grade fluorocarbon polymer chelate membrane is used to remove trace metal ions through a reaction. The retentate side of the third filter membrane 5 is returned to the second filter membrane 4, resulting in effective removal and increased product yield. The membrane's relatively small pore size also allows for the removal of particulate matter.

[0048] The preparation method of the fluorocarbon polymer chelate membrane is as follows:

[0049] Step 1: The porous PTFE membrane is subjected to hydrophilic treatment to obtain a hydrophilic base membrane;

[0050] Step 2: The chelating resin is washed with hydrochloric acid solution, sodium hydroxide solution and deionized water in sequence and then dried;

[0051] Step 3: Grinding and sieving the cleaned and dried chelating resin to obtain a powder;

[0052] Step 4: mixing the powder with polyisobutylene and polyhexafluoroethylene emulsion, and vacuum degassing to form a coating liquid;

[0053] Step 5: coating the coating liquid on a hydrophilic base film to form a chelating film;

[0054] Step 6: The prepared chelating membrane is washed with hydrochloric acid solution, sodium hydroxide solution and pure water in sequence until neutral, and then dried and stored.

[0055] The present invention removes metal ions through two membrane technologies, the second filter membrane 4 and the third filter membrane 5, so that the metal ion requirements in the SEMI-C12 standard are met; the membrane materials of the two membranes have little dissolution, reaching the semiconductor level; in addition to removing metal ions, the two membranes can also remove particulate matter, thereby improving the product purity of ultra-high purity methanol.

[0056] like Figure 2 As shown, a method for producing ultra-high purity methanol comprises the following steps:

[0057] S1: heating low-purity methanol;

[0058] Specifically, low-purity methanol enters the heater 1 from the first inlet 10 and is heated to 50-100°C.

[0059] S2: removing water content from low-purity methanol;

[0060] Specifically, the heated low-purity methanol enters from the first inlet 30 of the first filter membrane 3, the absolute pressure of the first permeate side 32 of the first filter membrane 3 is 1000-8000 Pa, and the water content that passes through the first permeate side 32 of the first filter membrane 3 is condensed by the first condensation device 7 and then discharged.

[0061] S3: Removal of organic impurities and most metal ions in low-purity methanol;

[0062] Step S3 specifically includes:

[0063] S30: removing lighter organic impurities in low-purity methanol;

[0064] Specifically, after the low-purity methanol from the first retentate side 31 of the first filter membrane 3 enters the light-removal tower 20, the lighter organic impurities such as alcohols, aldehydes, ketones, and esters in the methanol are removed; wherein the operating temperature of the light-removal tower 20 is 40-70°C, the operating pressure is 0-50kPa, and the reflux ratio is 0.5-30.

[0065] S31: Remove most of the metal ions and organic impurities with higher boiling points than methanol in low-purity methanol.

[0066] The bottoms from light-removal column 20 then enter heavy-removal column 21, where organic impurities such as alcohols, aldehydes, ketones, and esters with higher boiling points than methanol, as well as most metal ions, are removed. Heavy-removal column 21 operates at a temperature of 60-90°C, a pressure of 0-50 kPa, and a reflux ratio of 0.5-30.

[0067] S4: further removing metal ions and particulate matter from low-purity methanol;

[0068] Specifically, the low-purity methanol discharged from the top outlet 214 of the second distillation tower 210 enters the second filter membrane 4 to further remove some metal ions and particulate matter. The feedstock on the second retentate side 41 of the second filter membrane 4 then enters the first inlet 203 of the lightness removal tower 20, and step S3 is repeated. The operating temperature of step S4 is 40-70°C, and the absolute pressure on the second permeate side 42 is 1000-8000 Pa.

[0069] S5: Cooling the low-purity methanol.

[0070] Specifically, the methanol coming out of the permeate side 42 of the second filter membrane 4 enters the second condensation device 8 for cooling.

[0071] S6: Remove metal ions and particulate matter from low-purity methanol again.

[0072] Specifically, the methanol cooled by the second condensation device 8 enters the third filter membrane 5 for processing to further remove metal ions and particulate matter; and the raw material located on the third retentate side 51 of the third filter membrane 5 enters again from the second inlet 40 of the second filter membrane 4, and step S4 is performed again. The third permeate side 52 of the third filter membrane 5 is the final ultra-high purity methanol.

[0073] In order to better understand the present invention, the specific steps of a method for producing ultra-high purity methanol are further described below through two specific examples:

[0074] Example 1:

[0075] Step 1: Heat low-purity methanol to 100°C.

[0076] Step 2: Methanol heated to 100° C. enters the molecular sieve membrane / ceramic composite membrane (first filter membrane 3 ), the absolute pressure on the permeate side of which is 3000 Pa, and water in the methanol is removed.

[0077] Step 3: The first retentate side 31 of the first filter membrane 3 enters the first distillation tower 200. The top operating temperature of the first distillation tower 200 is 45°C, the bottom operating temperature is 70°C, the top operating pressure is 50 kPa, and the reflux ratio is 15. The lighter organic impurities such as alcohols, aldehydes, ketones, and esters are separated from the top of the tower.

[0078] The bottom components of the first distillation tower 200 enter the second distillation tower 210. The top operating temperature of the second distillation tower 210 is 60°C, the bottom operating temperature is 80°C, the top operating pressure is 0 kPa, and the reflux ratio is 20. Components with higher boiling points than methanol in the bottom of the second distillation tower 210, such as alcohols, aldehydes, ketones, and esters, and most of the metal ions are separated.

[0079] Step 4: The top fraction of the second distillation column 210 enters the polysulfonated vinyl chloride ether polymer / PTFE membrane (second filter membrane 4) to further remove some metal ions and particulate matter. The operating temperature of step 4 is 50°C, and the absolute pressure of the second permeate side 42 is 3000 Pa.

[0080] Step 5: The components on the second permeate side 42 of the second filter membrane 4 enter the second condensation device 8 for cooling; the components on the second retentate side 41 of the second filter membrane 4 enter the first distillation tower 200 again, and step 3 is performed again.

[0081] Step 6: After cooling through the second condenser 8, the components enter a polysulfonated vinyl chloride ether-imidodiacetate chelating membrane / PTFE (third filter membrane 5) to further remove metal ions and particulate matter. The third retentate side 51 of the third filter membrane 5 enters the second filter membrane 4 again, and step 4 is repeated. The third permeate side 52 of the third filter membrane 5 is ultra-high-purity methanol. The analysis results of the ultra-high-purity methanol are shown in Table 1.

[0082] Example 2:

[0083] Step 1: Heat low-purity methanol to 80°C.

[0084] Step 2: Methanol heated to 90° C. enters the PVA / PVDF / PET organic composite membrane (first filter membrane 3 ), the absolute pressure on the permeate side of which is 3000 Pa, and water in the methanol is removed.

[0085] Step 3: The first retentate side 31 of the first filtration membrane 3 enters the first distillation tower 200. The first distillation tower 200 operates at a top temperature of 40°C, a bottom temperature of 70°C, a top pressure of 50 kPa, and a reflux ratio of 15. Lighter organic impurities such as alcohols, aldehydes, ketones, and esters are separated from the top of the tower.

[0086] The bottom components of the first distillation tower 200 enter the second distillation tower 210. The top operating temperature of the second distillation tower 210 is 60°C, the bottom operating temperature is 80°C, the top operating pressure is 0 kPa, and the reflux ratio is 15. Components with higher boiling points than methanol in the bottom of the second distillation tower, such as alcohols, aldehydes, ketones, and esters, and most of the metal ions, are separated.

[0087] Step 4: The top fraction of the second distillation tower 210 enters the polyhexafluoropropylene / PTFE membrane (second filter membrane 4) to further remove some metal ions and particulate matter. The operating temperature of step 4 is 50°C, and the absolute pressure of the second permeate side 42 is 3000Pa.

[0088] Step 5: The components on the second permeate side 42 of the second filter membrane 4 enter the second condensation device 8 for cooling; the components on the second retentate side 41 of the second filter membrane 4 enter the first distillation tower 200 again, and step 3 is performed again.

[0089] Step 6: After cooling through the second condenser 8, the components enter a polyhexafluoropropylene-imidodiacetate chelating membrane / PTFE (third filter membrane 5) to further remove metal ions and particulate matter. The third retentate side 51 of the third filter membrane 5 enters the second filter membrane 4 again, and step 4 is repeated. The third permeate side 52 of the third filter membrane 5 is ultra-high-purity methanol. The analysis results of the ultra-high-purity methanol are shown in Table 1.

[0090] Table 1 Analysis results

[0091]

[0092]

[0093] The above table is intended to illustrate the components contained in the methanol raw material. The content of the components is closely related to the source, but it does not limit the applicability of the invention. The methanol products produced by the production device and method provided by the invention can meet the standard requirements of SEMIC12 (G4) and above.

[0094] The present invention removes metal ions through two membrane technologies, the second filter membrane 4 and the third filter membrane 5, so that the metal ion requirements in the SEMI-C12 standard are met; the membrane materials of the two membranes have little dissolution, reaching the semiconductor level; in addition to removing metal ions, the two membranes can also remove particulate matter, thereby improving the product purity of ultra-high purity methanol.

[0095] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A production device for ultra-high purity methanol, characterized in that: The invention comprises a heater (1), a distillation device (2), a first filter membrane (3), a second filter membrane (4) and a third filter membrane (5), wherein the first inlet (30) of the first filter membrane (3) is connected to the first outlet (11) of the heater (1), and the first retentate side (31) of the first filter membrane (3) is connected to the first inlet (203) of the distillation device (2); the second inlet (40) of the second filter membrane (4) is connected to the tower top outlet (214) of the distillation device (2), and the second retentate side (41) of the second filter membrane (4) is connected to the first inlet (203) of the distillation device (2); the second permeate side (42) of the second filter membrane (4) is connected to the third inlet (50) of the third filter membrane (5), and the third retentate side (51) of the third filter membrane (5) is connected to the second inlet (40) of the second filter membrane (4); The first filter membrane (3) is an organic composite membrane, an inorganic composite membrane, or an organic-inorganic composite water-permeable membrane, and is used to filter water in methanol; The second filter membrane (4) is an organic composite membrane, the support layer of the second filter membrane (4) is polytetrafluoroethylene, and the separation layer is a fluorine-containing polymer; The third filter membrane (5) is an organic composite membrane, the support layer of the third filter membrane (5) is polytetrafluoroethylene, and the separation layer is a fluorocarbon polymer chelate membrane; The fluorocarbon polymer chelate membrane is prepared by the following method: The porous PTFE membrane is subjected to hydrophilic treatment to obtain a hydrophilic base membrane; The chelating resin is washed with hydrochloric acid solution, sodium hydroxide solution and deionized water in sequence and then dried; Grinding and sieving the cleaned and dried chelating resin to obtain powder; The powder is mixed with polyisobutylene and polyhexafluoroethylene emulsion, and vacuum degassing is performed to form a coating liquid; The coating liquid is applied on a hydrophilic base film to form a chelating film; The prepared chelating membrane is washed with hydrochloric acid solution, sodium hydroxide solution and pure water in sequence until it becomes neutral, and then dried for storage.

2. The production device of ultra-high purity methanol according to claim 1, characterized in that: The distillation device (2) comprises a light removal tower (20) and a heavy removal tower (21), wherein the bottom outlet (204) of the light removal tower (20) is connected to the second inlet (213) of the heavy removal tower (21), the light removal tower (20) is provided with the first inlet (203), and the heavy removal tower (21) is provided with the top outlet (214).

3. The production device of ultra-high purity methanol according to claim 1, characterized in that: The production device further comprises a first condensation device (7), wherein a second inlet (700) of the first condensation device (7) is connected to the first permeation side (32) of the first filter membrane (3).

4. The production device of ultra-high purity methanol according to claim 1, characterized in that: The production device further includes a second condensation device (8) arranged between the second filter membrane (4) and the third filter membrane (5), the third inlet (800) of the second condensation device (8) is connected to the second permeate side (42) of the second filter membrane (4), and the third outlet (801) of the second condensation device (8) is connected to the third inlet (50) of the third filter membrane (5).

Images