A method for purifying high-purity anhydrous ethanol

Abstract

The present application relates to the field of purification of anhydrous ethanol, and particularly relates to a purification method of high-purity anhydrous ethanol. The purification method of high-purity anhydrous ethanol comprises the following preparation steps: S1, preliminary adsorption; S2, photocatalytic impurity removal; and S3, refining and purification. The present application realizes the preparation of high-purity anhydrous ethanol through the three-step synergistic process of preliminary adsorption, photocatalytic impurity removal and refining and purification. Targeted treatment steps are designed for different types of impurities (moisture, organic impurities and metal ions) in ethanol; the three-step process is sequentially progressive, forming a continuous processing system, which not only avoids the limitations of a single method, but also improves the impurity removal efficiency through step-by-step focusing, and finally realizes the significant improvement of the purity of ethanol.

Description

Technical Field

[0001] This invention relates to the field of anhydrous ethanol purification, and more specifically to a method for purifying high-purity anhydrous ethanol. Background Technology

[0002] High-purity anhydrous ethanol for scientific research is a crucial reagent in basic chemical research, high-end material synthesis, precision instrument analysis, and biomedical experiments. Its purity directly determines the accuracy and repeatability of experimental results. In semiconductor material preparation, trace metal ions in ethanol can lead to defects in chip circuits; in organic synthesis, water can disrupt anhydrous reaction systems; and in mass spectrometry analysis, impurities such as aldehydes, ketones, and acids can interfere with the detection baseline. Therefore, the purity requirements for anhydrous ethanol in scientific research are far higher than those for industrial-grade products, necessitating strict control over the content of water, metal ions, and trace organic impurities.

[0003] Current purification technologies for anhydrous ethanol used in scientific research mainly revolve around three core steps: dehydration, impurity removal, and trace removal. The mainstream methods include four categories: First, azeotropic distillation, which involves adding an azeotropic agent to water to form a low-boiling-point azeotrope, and then separating the water through distillation. This method is suitable for the preliminary purification of industrial-grade ethanol. Second, adsorption, which utilizes the selective adsorption of water molecules or uses porous membrane materials such as polyvinylidene fluoride and ceramic membranes to retain solid impurities and some large organic molecules through pore size sieving. At the same time, the porous structure of activated carbon is also used to adsorb organic impurities such as aldehydes, ketones, and acids, thereby helping to improve the purity of ethanol.

[0004] Regarding the aforementioned existing technologies, the inventors discovered that although they can improve ethanol purity to some extent, they have significant overall drawbacks: azeotropic distillation requires the introduction of azeotropic agents, which can easily lead to the residue of toxic impurities; molecular sieve adsorption is prone to producing micro-powder that contaminates ethanol due to high-temperature regeneration and requires frequent switching of adsorption columns to interrupt the process; traditional membrane separation suffers from a contradiction between permeability and retention rate, making it difficult to balance efficiency and retention effect; activated carbon adsorption has poor selectivity, which can lead to ethanol waste and cannot effectively remove trace metal ions. At the same time, these methods generally have high energy consumption and weak continuous operation capability. Even when using combined processes, it is impossible to overcome the core bottlenecks of trace impurity residue, unstable continuous operation, and high energy consumption. Overall, they are unable to meet the stringent requirements for purity, stability, and safety of high-purity anhydrous ethanol used in scientific research. Summary of the Invention

[0005] In view of the technical problems existing in the prior art, the present invention provides a method for purifying high-purity anhydrous ethanol.

[0006] A method for purifying high-purity anhydrous ethanol includes the following preparation steps:

[0007] S1. Preliminary adsorption: Take the ethanol to be purified and deliver it to the adsorption column. Adjust the ethanol flow rate to 5-8 L / h. When the water content at the adsorption column outlet is >50 ppm, switch to the adsorption column to continue adsorption.

[0008] S2. Photocatalytic purification: Collect the ethanol after adsorption by the adsorption column and transport it to the fixed bed photocatalytic reactor. Fill the fixed bed photocatalytic reactor with photocatalyst material. Under ultraviolet light irradiation, adjust the ethanol flow rate to 3-5 L / h and the reaction temperature to 25-35℃ for secondary purification and collect the purified ethanol.

[0009] S3. Refining and purification: Take the ethanol that has been purified twice and then purify it through an ultrafiltration membrane. Adjust the operating pressure to 0.2-0.4MPa and the permeate flow rate to 2-3L / h. After removing metal ions, high-purity anhydrous ethanol can be prepared.

[0010] Through the above technical solution, this application achieves the preparation of high-purity anhydrous ethanol via a three-stage synergistic process of preliminary adsorption, photocatalytic impurity removal, and refining purification. Targeted treatment steps are designed for different types of impurities in ethanol (water, organic impurities, and metal ions): preliminary adsorption utilizes the selective adsorption characteristics of an adsorption column to remove water, laying a low-water foundation for subsequent processing; photocatalytic impurity removal leverages the catalytic activity of a photocatalyst under ultraviolet light to oxidize and decompose organic impurities such as aldehydes and ketones; refining purification uses the sieving effect of an ultrafiltration membrane to retain metal ions. These three steps proceed sequentially, forming a continuous processing system that avoids the limitations of single methods and improves impurity removal efficiency through step-by-step focusing, ultimately achieving a significant increase in ethanol purity.

[0011] Furthermore, the adsorption material filled in the adsorption column includes UiO-66-NH2 metal framework organic adsorption material.

[0012] Through the above technical solution, this application clearly defines an adsorption column filled with UiO-66-NH2 metal framework organic adsorbent material. Due to its regular porous structure and abundant surface affinity sites, it exhibits specific adsorption capacity for water molecules. Compared to traditional adsorbent materials, the porous structure of UiO-66-NH2 provides ample adsorption channels, while the amino groups on its surface can form hydrogen bonds with water molecules, enhancing the selective adsorption of water. This characteristic enables more efficient removal of water from ethanol in the initial adsorption stage, reducing impurity interference in subsequent photocatalysis and membrane separation steps, providing higher-quality intermediate products for the overall purification process, and indirectly improving the purity and stability of the final product.

[0013] Furthermore, the surface of the UiO-66-NH2 metal framework organic adsorbent material is also coated with a modified layer, and the UiO-66-NH2 metal framework organic adsorbent material coated with the modified layer is made using the following technical solution:

[0014] Take UiO-66-NH2 metal framework organic adsorbent material and place it in anhydrous ethanol, stir and mix, and then disperse it by ultrasonication. Collect the dispersion and add aminopropyltriethoxysilane. After the addition is complete, heat up and keep it at the temperature for reaction, then filter and collect the activated particles.

[0015] Take the activated particles and add them to anhydrous ethanol. Add perfluorooctyltriethoxysilane, heat and keep warm under reflux reaction. After purification and cooling to room temperature, wash and dry to prepare UiO-66-NH2 metal framework organic adsorbent material with modified layer.

[0016] Through the above technical solution, this application modifies UiO-66-NH2 by constructing a synergistic structure of hydrophilic adsorption and hydrophobic protection through a two-step modification: first, activation with aminopropyltriethoxysilane introduces hydrophilic sites on the material surface, enhancing its adsorption capacity for water molecules; then, grafting with perfluorooctyltriethoxysilane forms a hydrophobic layer, reducing the adsorption of ethanol molecules on the material surface. This design retains the high water adsorption tendency of UiO-66-NH2 while blocking ethanol through the hydrophobic layer, solving the problem of traditional adsorption materials adsorbing both water and ethanol. In terms of performance, the modified material exhibits significantly improved adsorption selectivity, not only increasing dehydration efficiency but also reducing ethanol loss. Furthermore, its stability after washing and drying is enhanced, extending the material's recycling cycle.

[0017] Furthermore, the photocatalyst material includes at least one of nano-titanium dioxide particles and nano-zinc oxide particles.

[0018] Through the above technical solution, this application specifies that the photocatalyst material is nano-titanium dioxide or zinc oxide. The principle is that under ultraviolet light irradiation, the valence band electrons of these semiconductor materials are excited to the conduction band, forming photogenerated electron-hole pairs. These charge carriers have strong redox properties and can react with organic impurities such as aldehydes, ketones, and acids in ethanol, oxidizing and decomposing them into harmless small molecules. Compared with other catalysts, nano-titanium dioxide and zinc oxide have the characteristics of high chemical stability, strong photocatalytic activity, and a wide range of degradation capabilities for organic impurities. In terms of effectiveness, they can effectively reduce the content of organic impurities in the photocatalytic impurity removal process, providing a low-impurity substrate for subsequent purification and ensuring effective control of trace organic impurities in the final product.

[0019] Furthermore, the photocatalyst material is nano-titanium dioxide particles loaded with Pd nanoparticles.

[0020] Through the above technical solution, this application limits the photocatalyst to nano-titanium dioxide loaded with Pd nanoparticles. The principle is that Pd, as a noble metal additive, can accelerate the transfer of photogenerated electrons in nano-titanium dioxide and inhibit the recombination of electron-hole pairs, thereby improving the quantum efficiency of the photocatalytic reaction. Nano-titanium dioxide itself has strong oxidizing properties, but the easy recombination of photogenerated carriers limits its activity. However, the loading of Pd can construct an efficient electron transport channel, allowing more photogenerated holes to participate in the oxidation reaction of organic impurities. In terms of effect, compared with pure nano-titanium dioxide, the photocatalytic activity of the Pd-loaded catalyst is significantly improved, the degradation rate of organic impurities is accelerated, the reaction time for photocatalytic impurity removal is shortened, and the thoroughness of impurity removal is improved.

[0021] Furthermore, the photocatalyst material also includes a molecular sieve coating shell, which coats the outer peripheral surface of the nano-titanium dioxide particles loaded with Pd nanoparticles.

[0022] Through the above technical solution, this application coats a molecular sieve shell around Pd-loaded nano-titanium dioxide, utilizing the pore size sieving effect of the molecular sieve: the molecular sieve has a uniform microporous structure, allowing only small organic impurities such as aldehydes and ketones to pass through, while ethanol molecules, due to their larger size, are blocked outside the shell. This design allows organic impurities to enter the catalyst interior and contact the active sites for degradation, while avoiding excessive oxidation caused by direct interaction between ethanol molecules and the catalyst. This achieves selective impurity removal through targeted degradation of impurities and efficient retention of ethanol, solving the problem of easy oxidation of ethanol in traditional photocatalysis. It ensures the impurity removal effect while reducing ethanol loss, improving the economics of the purification process.

[0023] Furthermore, the bulk density of the photocatalyst material is 0.5-0.7 g / cm³. 3 The ultraviolet light irradiation power is 40-60W, and the light intensity is 8-12mW / cm². 2 .

[0024] Furthermore, the ultrafiltration membrane is manufactured using the following technical solution:

[0025] Graphene oxide and nano-SiO2 were mixed, anhydrous ethanol was added and ultrasonically dispersed, and a black slurry was collected.

[0026] The PVDF support layer is laid on the sand core funnel, the vacuum filtration device is assembled and the black slurry is slowly poured in, the vacuum pump is turned on and the slurry is filtered until the slurry is completely film formed. After washing the membrane surface with anhydrous ethanol, it is transferred to a vacuum drying oven and dried at a constant temperature of 110-130℃ for 4-6 hours. After naturally cooling to room temperature, the PVDF support layer is peeled off to obtain the ultrafiltration membrane.

[0027] Through the above technical solution, this application constructs a porous structure by combining graphene oxide and nano-SiO2: graphene oxide has a sheet-like structure that can form a continuous membrane framework, while nano-SiO2 filling the spaces between it can regulate the pore size distribution of the membrane and enhance its mechanical strength; vacuum filtration ensures uniform membrane formation, while high-temperature drying promotes structural stability. This composite membrane combines the surface affinity of graphene oxide with the sieving properties regulated by nano-SiO2, enabling efficient retention of metal ions in ethanol. In terms of performance, the prepared ultrafiltration membrane ensures good permeability of ethanol while achieving efficient retention of trace metal ions, completing the final purification step and ensuring that the product meets research-grade high-purity standards.

[0028] In summary, this application has the following beneficial effects:

[0029] First, this application achieves targeted and stepwise removal of water, organic impurities, and metal ions from ethanol through a three-stage continuous process of "preliminary adsorption - photocatalytic impurity removal - refining and purification." Compared to the intermittent operation of traditional single or combined processes, the three-stage synergistic system eliminates the need for frequent process interruptions and equipment switching, enabling continuous and stable processing of raw materials and significantly improving purification efficiency. Simultaneously, each stage is specifically tailored to the characteristics of the impurities: the adsorption column focuses on dehydration, the photocatalytic reactor focuses on the degradation of organic impurities, and the ultrafiltration membrane precisely retains metal ions. This avoids the limitations of traditional methods that require a single process to handle multiple impurities, significantly improving the thoroughness of impurity removal and providing an efficient and stable technical route for the preparation of high-purity anhydrous ethanol.

[0030] Secondly, this application significantly improves the economic efficiency and environmental friendliness of the purification process. The modified UiO-66-NH2 adsorbent material, through its hydrophilic-hydrophobic synergistic structure, enhances dehydration capacity while reducing ethanol loss; the Pd-loaded molecular sieve-coated photocatalyst, with its directional catalytic properties, avoids waste caused by excessive ethanol reaction; and the composite ultrafiltration membrane extends its service life through high-efficiency retention and stable performance. These materials not only improve their own recycling efficiency and reduce the frequency of consumable replacement, but also reduce energy and raw material consumption during the purification process, aligning with the development trend of green chemistry and balancing purification effect with cost control.

[0031] Third, the high-purity anhydrous ethanol prepared in this application fully meets the stringent purity requirements of the scientific research field. Through a three-stage purification process, trace impurities that are difficult to handle by traditional methods are effectively removed, ensuring that key indicators such as moisture, organic impurities, and metal ions in the product meet scientific research standards. This provides a reliable guarantee for fields sensitive to reagent purity, such as precision chemical experiments, high-end material synthesis, and biomedical research. It can reduce experimental errors or deviations in results caused by reagent impurities, improve the accuracy and repeatability of scientific research results, and expand the application value of anhydrous ethanol in high-end scientific research scenarios. Detailed Implementation

[0032] The present application will be further described in detail below with reference to the embodiments.

[0033] Preparation Example 1

[0034] UiO-66-NH2 metal framework organic adsorbent material

[0035] Weigh 86g ZrCl4 and 78g H2BDC-NH2, mix them, and add 3000mL anhydrous DMF; stir at 60℃ for 30min to form a solution; transfer the solution to a sealed reactor, react at 120℃ for 24h, cool naturally to room temperature, centrifuge the reaction solution at 8000r / min for 15min, and collect the white precipitate; wash 3 times with anhydrous DMF, and then wash 2 times with anhydrous ethanol; dry the precipitate under vacuum at 60℃ for 12h, cool it, grind it through a 200-mesh sieve to obtain UiO-66-NH2 powder.

[0036] Preparation Example 2

[0037] UiO-66-NH2 metal framework organic adsorbent material coated with modified layer 1

[0038] Take 50g of UiO-66-NH2 powder, add 1000mL of anhydrous ethanol, stir magnetically at 300r / min for 10min, then ultrasonically disperse at 200W for 30min, and collect the suspension.

[0039] Under nitrogen protection, 6g APTES was slowly added dropwise. After the addition was complete, 5mL of deionized water was added. The temperature was raised to 35℃ and stirred for 3h. After the reaction, the solid particles were collected by centrifugation at 6000r / min for 10min and washed three times with anhydrous ethanol to prepare activated particles.

[0040] Take 40g of activated particles, add 800mL of anhydrous ethanol, ultrasonically disperse for 20min at 300W, add 4g of FOTS, stir to dissolve, heat to 78℃, keep warm and reflux for 5h, cool to room temperature after reaction, centrifuge at 6000r / min for 10min, wash the solid three times with anhydrous ethanol and twice with n-hexane, and vacuum dry at 60℃ for 8h to obtain UiO-66-NH2 metal framework organic adsorbent material 1 coated with modified layer.

[0041] Preparation Example 3

[0042] UiO-66-NH2 metal framework organic adsorbent material coated with modified layer 2

[0043] Take 65g of UiO-66-NH2 powder, add 1250mL of anhydrous ethanol, stir magnetically at 300r / min for 10min, then ultrasonically disperse at 250W for 30min, and collect the suspension.

[0044] Under nitrogen protection, 8g of APTES was slowly added dropwise. After the addition was complete, 7.5mL of deionized water was added, the temperature was raised to 35℃, and the reaction was stirred for 3h. After the reaction, the solid particles were collected by centrifugation at 6000r / min for 10min and washed three times with anhydrous ethanol to prepare activated particles.

[0045] Take 45g of activated particles, add 900mL of anhydrous ethanol, and ultrasonically disperse for 20min at 300W. Add 4.5g of FOTS, stir to dissolve, and heat to 81.5℃. Keep warm and reflux for 6.5h. After the reaction, cool to room temperature, centrifuge at 6000r / min for 10min, wash the solid three times with anhydrous ethanol and twice with n-hexane, and vacuum dry at 60℃ for 8h to obtain UiO-66-NH2 metal framework organic adsorbent material 2 coated with modified layer.

[0046] Preparation Example 4

[0047] UiO-66-NH2 metal framework organic adsorbent material coated with modified layer 3

[0048] Take 80g of UiO-66-NH2 powder, add 1500mL of anhydrous ethanol, stir magnetically at 300r / min for 10min, then sonicate at 300W for 30min, and collect the suspension.

[0049] Under nitrogen protection, 10g APTES was slowly added dropwise. After the addition was complete, 10mL of deionized water was added. The temperature was raised to 35℃ and stirred for 3h. After the reaction, the solid particles were collected by centrifugation at 6000r / min for 10min and washed three times with anhydrous ethanol to prepare activated particles.

[0050] Take 50g of activated particles, add 1000mL of anhydrous ethanol, and ultrasonically disperse for 20min at 300W. Add 5g of FOTS, stir to dissolve, and heat to 85℃. Keep warm and reflux for 8h. After the reaction, cool to room temperature, centrifuge at 6000r / min for 10min, and wash the solid three times with anhydrous ethanol and twice with n-hexane. Dry under vacuum at 60℃ for 8h to obtain UiO-66-NH2 metal framework organic adsorbent material 3 coated with modified layer.

[0051] Preparation Example 5

[0052] Photocatalyst 1

[0053] Weigh 40g of TiO2 particles, add 2400mL of ethylene glycol, and sonicate for 1500min to obtain a suspension; weigh 0.8g of PdCl2, add 800mL of ethylene glycol, and stir at 75℃ until completely dissolved to obtain a solution; pour the solution into the suspension, stir for 800min, and adjust the pH of the mixture to 8-9 with 0.08mol / L NaOH; under nitrogen protection, react at 75℃ in an oil bath for 300h; after the reaction, cool to room temperature, centrifuge to collect the black precipitate, wash three times with anhydrous ethanol, and vacuum dry at 55℃ for 600h to obtain photocatalyst 1.

[0054] Preparation Example 6

[0055] Photocatalyst 2

[0056] Weigh 50g of TiO2 particles, add 3000mL of ethylene glycol, and sonicate for 2000min to obtain a suspension; weigh 1.0g of PdCl2, add 1000mL of ethylene glycol, and stir at 80℃ until completely dissolved to obtain a solution; pour the solution into the suspension, stir for 1000min, and adjust the pH of the mixture to 8-9 with 0.10mol / L NaOH; under nitrogen protection, react at 80℃ in an oil bath for 400h; after the reaction, cool to room temperature, centrifuge to collect the black precipitate, wash three times with anhydrous ethanol, and vacuum dry at 60℃ for 800h to obtain photocatalyst 2.

[0057] Preparation Example 7

[0058] Photocatalyst 3

[0059] Weigh 60g of TiO2 particles, add 3600mL of ethylene glycol, and sonicate for 2500min to obtain a suspension; weigh 1.2g of PdCl2, add 1200mL of ethylene glycol, and stir at 85℃ until completely dissolved to obtain a solution; pour the solution into the suspension, stir for 1200min, and adjust the pH of the mixture to 8-9 with 0.12mol / L NaOH; under nitrogen protection, react at 85℃ in an oil bath for 500h; after the reaction, cool to room temperature, centrifuge to collect the black precipitate, wash three times with anhydrous ethanol, and vacuum dry at 65℃ for 1000h to obtain photocatalyst 3.

[0060] Preparation Example 8

[0061] Photocatalyst 4

[0062] Take 10g of photocatalyst 1, add 100mL of anhydrous ethanol, and ultrasonically disperse for 30min to form a uniform suspension; add 0.5mL of 0.1mol / L ammonia to adjust the pH to 9-10, stir magnetically for 10min, collect the particles by centrifugation, wash twice with anhydrous ethanol, and vacuum dry at 60℃ for 2h for later use; take 50mL of deionized water and 10mL of LTPAOH solution, stir magnetically for 10min, add 8mL of LTEOS, and continue stirring for 30min to form a transparent silica sol; add the pretreated photocatalyst 1 to the above silica sol. The particles were ultrasonically dispersed for 20 min and then transferred to a magnetically stirred reactor. Under nitrogen protection, the temperature was raised to 100℃ and the reaction was carried out at a constant temperature with stirring for 8 h. After the reaction was completed, the particles were naturally cooled to room temperature, centrifuged at 15000 r / min for 20 min to collect the coated particles, and washed three times with deionized water. The coated particles were then transferred to a reactor, 50 mL of deionized water was added, and the particles were hydrothermally crystallized at 180℃ for 24 h. The particles were collected by centrifugation, vacuum dried at 60℃ for 6 h, and then placed in a muffle furnace and calcined at 550℃ for 6 h to remove the template agent TPAOH. The particles were then cooled to room temperature to obtain photocatalyst 4.

[0063] Preparation Example 9

[0064] Photocatalyst 5

[0065] Take 12.5g of photocatalyst 2, add 125mL of anhydrous ethanol, and ultrasonically disperse for 30min to form a uniform suspension; add 0.65mL of 0.1mol / L ammonia to adjust the pH to 9-10, stir magnetically for 12.5min, centrifuge to collect the particles, wash twice with anhydrous ethanol, and vacuum dry at 60℃ for 2h for later use; take 65mL of deionized water and 12.5mL of LTPAOH solution, stir magnetically for 10min, add 10mL of LTEOS, and continue stirring for 30min to form a transparent silica sol; add the pretreated photocatalyst 2 to the above... In silica sol, the mixture was ultrasonically dispersed for 20 min and then transferred to a magnetically stirred reactor. Under nitrogen protection, the temperature was raised to 110℃ and the mixture was stirred at a constant temperature for 10 h. After the reaction, the mixture was naturally cooled to room temperature, centrifuged at 15000 r / min for 20 min to collect the coated particles, and washed three times with deionized water. The coated particles were then transferred to a reactor, 50 mL of deionized water was added, and the mixture was hydrothermally crystallized at 180℃ for 24 h. The particles were collected by centrifugation, vacuum dried at 60℃ for 6 h, and then placed in a muffle furnace and calcined at 550℃ for 6 h to remove the template agent TPAOH. The mixture was then cooled to room temperature to obtain photocatalyst 5.

[0066] Preparation Example 10

[0067] Photocatalyst 6

[0068] Take 15g of photocatalyst 3, add 150mL of anhydrous ethanol, and ultrasonically disperse for 30min to form a uniform suspension; add 0.8mL of 0.1mol / L ammonia to adjust the pH to 9-10, stir magnetically for 15min, collect the particles by centrifugation, wash twice with anhydrous ethanol, and vacuum dry at 60℃ for 2h for later use; take 80mL of deionized water and 15mL of LTPAOH solution, stir magnetically for 10min, add 12mL of LTEOS, and continue stirring for 30min to form a transparent silica sol; add the pretreated photocatalyst 3 to the above silica sol. The particles were ultrasonically dispersed for 20 min and then transferred to a magnetically stirred reactor. Under nitrogen protection, the temperature was raised to 120℃ and the reaction was carried out at a constant temperature with stirring for 12 h. After the reaction was completed, the particles were naturally cooled to room temperature, centrifuged at 15000 r / min for 20 min to collect the coated particles, and washed three times with deionized water. The coated particles were then transferred to a reactor, 50 mL of deionized water was added, and the particles were hydrothermally crystallized at 180℃ for 24 h. The particles were collected by centrifugation, vacuum dried at 60℃ for 6 h, and then placed in a muffle furnace and calcined at 550℃ for 6 h to remove the template agent TPAOH. The mixture was then cooled to room temperature to obtain photocatalyst 6.

[0069] Preparation Example 11

[0070] Ultrafiltration membrane

[0071] Graphene oxide and nano-SiO2 were mixed at a ratio of 2.5:1 and collected as mixed particles. The mixed particles were then mixed with anhydrous ethanol at a solid-liquid mass ratio of 1:50 and ultrasonically dispersed at 200W to obtain a black slurry.

[0072] A PVDF support layer with a pore size of 0.22 μm and a thickness of 80 μm was laid on a sand core funnel. The slurry was poured at a flow rate of 5 mL / min under a vacuum of -0.05 MPa and filtered until the slurry completely formed a membrane. After washing the membrane surface with anhydrous ethanol, it was transferred to a vacuum drying oven and dried at a constant temperature of 120℃ for 5 h. After naturally cooling to room temperature, the PVDF support layer was peeled off at a speed of 3 mm / s to obtain the ultrafiltration membrane.

[0073] Example 1

[0074] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0075] S1. Preliminary Adsorption: Take ethanol with an initial water content of 50 ppm and an initial temperature of 20℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 50 mm and a height of 800 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material at a loading of 1.5 kg / column. Adjust the ethanol flow rate to 5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0076] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 80 mm, a height of 1000 mm, and an effective volume of 0.008 m³. 3 In the photocatalytic reactor, the reactor is filled with TiO2 photocatalyst at a loading amount of 2.0 kg and a bulk density of 0.5 g / cm³. 3 The particle size is 0.5 mm; under 40W light intensity of 8mW / cm². 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor to 0.1 MPa. The ethanol flow rate is adjusted to 3 L / h and the reaction temperature is 25℃ for secondary impurity removal.

[0077] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 15 minutes, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 30 minutes. By controlling the ultrafiltration system temperature at 25℃, the operating pressure at 0.2 MPa, the system back pressure at 0.05 MPa, and the permeate flow rate at 2 L / h, high-purity anhydrous ethanol can be prepared.

[0078] Example 2

[0079] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0080] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material at a loading rate of 2.0 kg / column. Adjust the ethanol flow rate to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >5 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0081] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3 In the photocatalytic reactor, the reactor is filled with TiO2 photocatalyst at a loading amount of 2.5 kg and a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0082] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0083] Example 3

[0084] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0085] S1. Preliminary Adsorption: Take ethanol with an initial water content of 200 ppm and an initial temperature of 30℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 80 mm and a height of 1200 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material at a loading of 2.5 kg / column. Adjust the ethanol flow rate to 8 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0086] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 120 mm, a height of 1500 mm, and an effective volume of 0.018 m³. 3 In the photocatalytic reactor, the reactor is filled with TiO2 photocatalyst, with a filling amount of 3.0 kg and a bulk density of 0.7 g / cm³. 3 The particle size is 1.0 mm; under 60W light intensity and 12mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.15 MPa. The ethanol flow rate is adjusted to 5 L / h and the reaction temperature is 35 °C for secondary impurity removal.

[0087] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 20 minutes, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 60 minutes. By controlling the ultrafiltration system temperature at 35℃, the operating pressure at 0.4 MPa, the system back pressure at 0.1 MPa, and the permeate flow rate at 3 L / h, high-purity anhydrous ethanol can be prepared.

[0088] Example 4

[0089] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0090] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material 1 coated with a modified layer, with a filling amount of 2.0 kg / column. Adjust the ethanol flow rate to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0091] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3 In the photocatalytic reactor, the reactor is filled with TiO2 photocatalyst at a loading amount of 2.5 kg and a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0092] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0093] Example 5

[0094] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0095] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material 2 coated with a modified layer, with a filling amount of 2.0 kg / column. Adjust the ethanol flow rate to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0096] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3In the photocatalytic reactor, the reactor is filled with TiO2 photocatalyst at a loading amount of 2.5 kg and a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0097] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0098] Example 6

[0099] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0100] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material 3 coated with a modified layer, with a filling amount of 2.0 kg / column. The ethanol flow rate is adjusted to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, the column is switched to the standby adsorption column to continue adsorption. The flow rate fluctuation during the switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0101] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3 In the photocatalytic reactor, the reactor is filled with TiO2 photocatalyst at a loading amount of 2.5 kg and a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0102] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0103] Example 7

[0104] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0105] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material 2 coated with a modified layer, with a filling amount of 2.0 kg / column. Adjust the ethanol flow rate to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0106] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3 In the photocatalytic reactor, photocatalyst 1 is filled with 2.5 kg of photocatalyst and has a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0107] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0108] Example 8

[0109] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0110] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material 2 coated with a modified layer, with a filling amount of 2.0 kg / column. Adjust the ethanol flow rate to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0111] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3 In the photocatalytic reactor, photocatalyst 2 was filled with 2.5 kg of photocatalyst, with a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0112] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0113] Example 9

[0114] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0115] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material 2 coated with a modified layer, with a filling amount of 2.0 kg / column. Adjust the ethanol flow rate to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0116] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3In the photocatalytic reactor, photocatalyst 3 was filled with 2.5 kg of photocatalyst and a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0117] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0118] Example 10

[0119] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0120] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material 2 coated with a modified layer, with a filling amount of 2.0 kg / column. Adjust the ethanol flow rate to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0121] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3 In the photocatalytic reactor, photocatalyst 4 was filled with 2.5 kg of photocatalyst and a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0122] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0123] Example 11

[0124] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0125] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material 2 coated with a modified layer, with a filling amount of 2.0 kg / column. Adjust the ethanol flow rate to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0126] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3 In the photocatalytic reactor, photocatalyst 5 was filled with 2.5 kg of photocatalyst, with a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0127] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0128] Example 12

[0129] A method for purifying high-purity anhydrous ethanol, characterized by comprising the following preparation steps:

[0130] S1. Preliminary Adsorption: Take ethanol with an initial water content of 125 ppm and an initial temperature of 25℃, and feed it into a 316L stainless steel adsorption column with an inner diameter of 65 mm and a height of 1000 mm. The column is filled with UiO-66-NH2 metal framework organic adsorption material 2 coated with a modified layer, with a filling amount of 2.0 kg / column. Adjust the ethanol flow rate to 6.5 L / h. A dual-column parallel design is adopted. When the water content at the outlet of the adsorption column is >50 ppm, switch to the standby adsorption column to continue adsorption. The flow rate fluctuation during switching is controlled within 0.5 L / h to ensure continuous feeding without interruption.

[0131] S2. Photocatalytic impurity removal: Collect the ethanol after adsorption by the adsorption column and transport it to a container with an inner diameter of 100 mm, a height of 1250 mm, and an effective volume of 0.013 m³. 3 In the photocatalytic reactor, photocatalyst 6 was filled with 2.5 kg of photocatalyst, with a bulk density of 0.6 g / cm³. 3 The particle size is 0.75 mm; under 50W light intensity and 10mW / cm² light intensity. 2 The reactor is subjected to ultraviolet light treatment, and a constant temperature jacket is installed on the outer wall to control the pressure inside the reactor at 0.125 MPa. The ethanol flow rate is adjusted to 4 L / h and the reaction temperature is 30 °C for secondary impurity removal.

[0132] S3. Refining and Purification: Take the ethanol that has undergone secondary impurity removal and transport it to the purification system of the ultrafiltration membrane. Before use, it needs to be ultrasonically cleaned with anhydrous ethanol for 17.5 min, and then pre-pressurized with anhydrous ethanol at a pressure of 0.1 MPa for 45 min. By controlling the ultrafiltration system temperature at 30℃, the operating pressure at 0.3 MPa, the system back pressure at 0.075 MPa, and the permeate flow rate at 2.5 L / h, high-purity anhydrous ethanol can be prepared.

[0133] Performance testing

[0134] Ethanol purity: GB / T678-2023 "Chemical Reagents - Ethanol (Anhydrous)";

[0135] Moisture content: GB / T 6283-2008 "Determination of Moisture Content in Chemical Products - Karl Fischer Method";

[0136] Total metal ion content: supplemented according to GB / T 3049-2006 "General Method for Determination of Iron Content in Industrial Chemical Products 1,10-Phenanthroline Spectrophotometric Method" + ICP-MS;

[0137] Total content of organic impurities (aldehydes / ketones / acids): GB / T23549-2021;

[0138] Meanwhile, the absorbance of the ethanol prepared in Examples 1-12 was measured, and the measurement standard was T / SDSCCE 057-2024.

[0139] The results are shown in Table 1-2 below:

[0140] Table 1 Performance Test Table

[0141]

[0142] By comparing the test results of Examples 1-12 above with those in Table 1, it can be found that:

[0143] The ethanol purified according to this application has a significantly improved purity, meeting the requirements of actual use;

[0144] Meanwhile, the water content of the products in Examples 4-6 was lower than that in Examples 1-3, demonstrating the high water absorption selectivity of the modified adsorption material; the organic impurity removal rate of Examples 7-9 was improved compared to Examples 4-6, and was further improved in Examples 10-12, proving that Pd loading enhances catalytic activity and molecular sieve shell achieves targeted impurity removal;

[0145] The ethanol purity of Example 11 reached 99.9998%, water content was 32 ppm, and organic impurities were 0.22 ppm, which is the optimal process combination. Its core lies in the three-stage synergistic effect of modified adsorption, molecular sieve coating catalysis, and ultrafiltration purification.

[0146] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

[0147] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0148] When this specification uses the prefixes “known to those skilled in the art,” “prior art,” or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those commonly used in the art at the time of this application, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0149] In the context of this specification, except where expressly stated otherwise, any matters or issues not mentioned shall apply directly to those known in the art without any modification.

Claims

1. A method for purifying high-purity anhydrous ethanol, characterized in that, The preparation steps include the following: S1. Preliminary adsorption: Take the ethanol to be purified and deliver it to the adsorption column. Adjust the ethanol flow rate to 5-8 L / h. When the water content at the adsorption column outlet is >50 ppm, switch to the adsorption column to continue adsorption. S2. Photocatalytic purification: Collect the ethanol after adsorption by the adsorption column and transport it to the fixed bed photocatalytic reactor. Fill the fixed bed photocatalytic reactor with photocatalyst material. Under ultraviolet light irradiation, adjust the ethanol flow rate to 3-5 L / h and the reaction temperature to 25-35℃ for secondary purification and collect the purified ethanol. S3. Refining and purification: Take the ethanol that has been purified twice and then purify it through an ultrafiltration membrane. Adjust the operating pressure to 0.2-0.4MPa and the permeate flow rate to 2-3L / h. After removing metal ions, high-purity anhydrous ethanol can be prepared.

2. The purification method for high-purity anhydrous ethanol according to claim 1, characterized in that, The adsorption material filled in the adsorption column includes UiO-66-NH2 metal framework organic adsorption material.

3. The purification method for high-purity anhydrous ethanol according to claim 1, characterized in that, The surface of the UiO-66-NH2 metal framework organic adsorbent material is further coated with a modified layer, and the UiO-66-NH2 metal framework organic adsorbent material coated with the modified layer is made using the following technical solution: Take UiO-66-NH2 metal framework organic adsorbent material and place it in anhydrous ethanol, stir and mix, and then disperse it by ultrasonication. Collect the dispersion and add aminopropyltriethoxysilane. After the addition is complete, heat up and keep it at the temperature for reaction, then filter and collect the activated particles. Take the activated particles and add them to anhydrous ethanol. Add perfluorooctyltriethoxysilane, heat and keep warm under reflux reaction. After purification and cooling to room temperature, wash and dry to prepare UiO-66-NH2 metal framework organic adsorbent material with modified layer.

4. The purification method for high-purity anhydrous ethanol according to claim 1, characterized in that, The photocatalyst material includes at least one of nano-titanium dioxide particles and nano-zinc oxide particles.

5. The purification method for high-purity anhydrous ethanol according to claim 4, characterized in that, The photocatalyst material is nano-titanium dioxide particles loaded with Pd nanoparticles.

6. The purification method for high-purity anhydrous ethanol according to claim 5, characterized in that, The photocatalyst material further includes a molecular sieve coating layer, which coats the outer peripheral surface of the nano-titanium dioxide particles loaded with Pd nanoparticles.

7. The purification method for high-purity anhydrous ethanol according to claim 6, characterized in that, The bulk density of the photocatalyst material is 0.5-0.7 g / cm³. 3 The ultraviolet light irradiation power is 40-60W, and the light intensity is 8-12mW / cm². 2 .

8. The purification method for high-purity anhydrous ethanol according to claim 6, characterized in that, The ultrafiltration membrane is manufactured using the following technical solution: Graphene oxide and nano-SiO2 were mixed, anhydrous ethanol was added and ultrasonically dispersed, and a black slurry was collected. The PVDF support layer is laid on the sand core funnel, the vacuum filtration device is assembled and the black slurry is slowly poured in, the vacuum pump is turned on and the slurry is filtered until the slurry is completely film formed. After washing the membrane surface with anhydrous ethanol, it is transferred to a vacuum drying oven and dried at a constant temperature of 110-130℃ for 4-6 hours. After naturally cooling to room temperature, the PVDF support layer is peeled off to obtain the ultrafiltration membrane.

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