Dehydration of glycol-containing mixtures with high water content using optimized pervaporation

Abstract

Systems and methods for dewatering a mixture of an organic liquid and water are disclosed. The mixture of the organic liquid and water is fed to a membrane. The mixture is then subjected to process conditions sufficient to cause pervaporation. A permeate comprising a higher weight percent of water than the mixture is recovered. A retentate comprising a higher weight percent of the organic liquid than the mixture is also recovered.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 202080019682.4, filed on January 9, 2020, entitled "Dehydration of a Diol-Containing Mixture with High Water Content Using an Optimized Pervaporation Method".

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 790,407, filed January 9, 2019, which is incorporated herein by reference in its entirety. Technical Field

[0003] This invention generally relates to liquid separation technology. More specifically, this invention relates to systems and methods for separating mixtures of water and organic liquids using pervaporation. Background Technology

[0004] Separation of liquid mixtures is a crucial process in the chemical industry for purifying products and / or recovering unreacted materials. Distillation is conventionally the most widely used technique for separating liquid components. However, several drawbacks, including high energy requirements, high steam consumption, and low single-pass separation efficiency, limit the economic feasibility of distillation.

[0005] The separation of water from organic compounds such as glycols, monohydric alcohols, and polyhydric alcohols typically requires extremely high energy expenditures. Due to azeotropic formation, the high heat capacity of water, and / or the close boiling point range between water and organic compounds, multi-stage distillation involving a series of distillation columns with high reflux rates is often employed. Therefore, the infrastructure and operating costs of distilling water-organic mixtures are generally high. Other technologies such as reverse osmosis, ultrafiltration, and nanofiltration have been explored as alternative methods for separating water from organic compounds. However, upgrading these technologies to commercial-grade methods is technically challenging due to factors such as low separation factors, low flux, and / or product loss.

[0006] In summary, although systems and methods exist for separating water from organic compounds, the field still needs improvement due to at least the aforementioned drawbacks of conventional methods. Summary of the Invention

[0007] Solutions have been found to at least some of the aforementioned problems associated with conventional methods for separating water and organic compounds. The solution lies in a method for dehydrating a mixture of organic liquids and water using a membrane under process conditions sufficient to induce pervaporation. Compared to distillation, this can advantageously reduce at least the energy consumption and infrastructure costs required to separate organic liquids from water. Notably, this method enables high membrane flux levels, resulting in low requirements for membrane surface area. Furthermore, implementing this method allows the membrane to have a high separation factor for water and organic liquids, including glycols, ethanol, and / or polyhydric alcohols, thereby reducing product loss. Moreover, the method of the present invention is more easily scalable to commercial-scale processes compared to other membrane-based separation methods. Therefore, the method of the present invention provides a technical solution to at least some of the problems associated with currently available methods for separating water and organic liquids.

[0008] Embodiments of the present invention include a method for dehydrating a mixture of an organic liquid and water. The method includes feeding the mixture into a membrane. The mixture contains at least 85% by weight of water and at most 15% by weight of an organic liquid. The method further includes subjecting the mixture in the membrane to process conditions sufficient to cause pervaporation. The process conditions include temperatures in the range of 85°C to 160°C. The method also includes recovering permeate containing a percentage by weight of water greater than the percentage by weight of water in the mixture and a residue containing a percentage by weight of organic liquid greater than the percentage by weight of organic liquid in the mixture.

[0009] Embodiments of the present invention include a method for dehydrating a mixture of an organic liquid and water. The method includes feeding the mixture into a membrane. The mixture contains at least 85% by weight of water and at most 15% by weight of an organic liquid. The method further includes subjecting the mixture in the membrane to process conditions sufficient to cause pervaporation. The process conditions include a temperature in the range of 85°C to 160°C and a pressure in the range of 3 bar to 8 bar. The method further includes recovering a permeate containing a weight percentage of water greater than the weight percentage of water in the mixture and a residue containing a weight percentage of organic liquid greater than the weight percentage of organic liquid in the mixture.

[0010] Embodiments of the present invention include a method for dehydrating a mixture of ethylene glycol and water. The method includes feeding the mixture into a membrane. The mixture contains at least 85% by weight of water and at most 15% by weight of an organic liquid. The method further includes subjecting the mixture in the membrane to process conditions sufficient to cause pervaporation. The process conditions include a temperature in the range of 85°C to 160°C and a pressure in the range of 3 bar to 8 bar. The method further includes recovering permeate containing a weight percentage of water greater than the weight percentage of water in the mixture and a residue containing a weight percentage of organic liquid greater than the weight percentage of organic liquid in the mixture.

[0011] The following includes definitions of all terms and expressions used throughout this specification.

[0012] The terms “about” or “approximately” are defined as close to, as understood by those skilled in the art. In one non-limiting embodiment, these terms are defined as within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%.

[0013] The terms “weight%”, “volume%”, or “molar%” refer to the weight, volume, or mole percentage of a component, based on the total weight, volume, or number of moles of the material containing that component. In a non-limiting example, 10 moles of a component in 100 moles of material constitutes 10 moles of the component.

[0014] The term “substantially” and its variations are defined as including deviations within 10%, 5%, 1%, or 0.5%.

[0015] When used in the claims and / or description, the terms “inhibit” or “reduce” or “prevent” or “avoid” or any variation thereof include any measurable reduction or complete inhibition to achieve the desired result.

[0016] The term "effective," as used in the specification and / or claims, means sufficient to achieve the desired, expected, or anticipated result.

[0017] The term "pervaporation," as used in the specification and / or claims, refers to the process of separating a liquid mixture by partial evaporation of the mixture through a membrane. Pervaporation combines osmosis and evaporation.

[0018] In the claims or description, when used in conjunction with the terms “comprising,” “including,” “containing,” or “having,” the singular noun may refer to “one,” but it also has the same meaning as “one or more,” “at least one,” and “one or more than one.”

[0019] The words “contain,” “have,” “include,” or “contain” are inclusive or open-ended and do not exclude other, undocumented elements or methods.

[0020] The method of the present invention may include, consist of, or be composed of specific ingredients, components, compositions, etc. disclosed throughout the specification.

[0021] The term "major," as used in the specification and / or claims, means greater than any one of 50 wt%, 50 mol%, and 50 vol%. For example, "major" may include all values ​​and ranges from 50.1 wt% to 100 wt%, from 50.1 mol% to 100 mol%, or from 50.1 vol% to 100 vol%.

[0022] Other objects, features, and advantages of the present invention will become apparent from the following drawings, detailed description, and embodiments. However, it should be understood that while the drawings, detailed description, and embodiments illustrate specific embodiments of the invention, they are given by way of illustration only and are not intended to be limiting. Furthermore, upon reading this detailed description, changes and modifications within the spirit and scope of the invention will be apparent to those skilled in the art. In further embodiments, features from a particular embodiment may be combined with features from other embodiments. For example, a feature from one embodiment may be combined with features from any other embodiment. In further embodiments, the specific embodiments described herein may be supplemented with additional features. Attached Figure Description

[0023] For a more comprehensive understanding, please refer to the following description in conjunction with the accompanying drawings, in which:

[0024] Figure 1 A schematic diagram of a separation process via pervaporation according to an embodiment of the present invention is shown; and

[0025] Figure 2 A schematic flowchart of a method for dehydrating a mixture of organic liquid and water according to an embodiment of the present invention is shown. Detailed Implementation

[0026] Currently, distillation is used to separate organic liquids and water when purifying organic liquids. Alternatively, reverse osmosis, ultrafiltration, and / or nanofiltration can also be used on a limited scale to separate organic liquids and water. However, these existing methods have several problems. Distillation of mixtures of organic liquids and water typically consumes a large amount of energy and requires multiple distillation columns in series, due to the formation of azeotropes between water and organic liquids. Therefore, operating costs can be high when using distillation to separate mixtures of organic liquids and water. Reverse osmosis, ultrafiltration, and / or nanofiltration require less energy than distillation. However, using these methods on an industrial scale is challenging due to the limited separation factor (SF) and the need for large membrane surfaces. This invention provides a solution to these problems. The solution is based on a method for dehydrating mixtures of organic liquids and water. The method involves separating water from organic liquids via pervaporation using one or more membranes. This method requires less energy than distillation. Furthermore, the infrastructure costs using this method are lower than those for distillation, which requires a series of distillation columns. Furthermore, compared to conventional reverse osmosis, ultrafiltration, and / or nanofiltration, this method improves membrane separation efficiency and increases the flux per unit area of ​​the membrane, thereby enabling scalability for commercial production. These and other non-limiting aspects of the invention will be discussed in further detail in the following sections.

[0027] A. Membrane module for separating organic liquids and water via pervaporation

[0028] In embodiments of the present invention, a pervaporation system for separating a mixture of organic liquid and water may include one or more membrane modules. (See also...) Figure 1 A schematic diagram of a membrane separation module 100 is shown, which, compared to conventional systems for separating mixtures of organic liquids and water, is capable of separating organic liquids from water with reduced energy consumption and high separation efficiency. According to embodiments of the invention, the membrane separation module 100 includes a frame-plate structure, a tubular module, a series-parallel network structure, a core-shell structure, a hollow fiber structure, or a combination thereof.

[0029] According to an embodiment of the invention, the membrane separation module 100 may include a frame 101. In an embodiment of the invention, the frame 101 is adapted to accommodate one or more membranes 102. According to an embodiment of the invention, the frame 101 is also adapted to receive and release a mixture stream 11 of organic liquid and water therein and from it a permeate stream 12 and / or a residual stream 13. In an embodiment of the invention, the permeate stream 12 may be released downstream of one or more membranes 102. The residual stream 13 may be released upstream of one or more membranes 102. In an embodiment of the invention, the permeate stream 12 mainly comprises water. The residual stream 13 may mainly comprise organic liquid. According to an embodiment of the invention, the membrane separation module 100 further includes a support member 103 disposed against the membrane 102. The support member 103 is adapted to support the membrane 102 so that the membrane 102 remains fixed. In an embodiment, the support member 103 is disposed on the side of the membrane 102 away from the mixture stream 11 of organic liquid and water. Non-limiting examples of support 103 may include polyvinyl alcohol, polysulfone, silicon dioxide, polyimide, zeolite, and combinations thereof.

[0030] In embodiments of the invention, membrane 102 is adapted to allow the vapor of an organic liquid to pass through while substantially blocking the passage of water. Membrane 102 may comprise one or more flat sheet membranes, one or more hollow fiber membranes, or combinations thereof. According to embodiments of the invention, the thickness of each membrane 102 is within all ranges and values ​​from 10 nm to 10 mm, including 10 nm to 20 nm, 20 nm to 30 nm, 30 nm to 40 nm, 40 nm to 50 nm, 50 nm to 60 nm, 60 nm to 70 nm, 70 nm to 80 nm, 80 nm to 90 nm, 90 nm to 100 nm, 100 nm to 200 nm, 200 nm to 300 nm, 300 nm to 400 nm, and 400 nm to 500 nm. The range of 0nm, 500nm to 600nm, 600nm to 700nm, 800nm ​​to 900nm, 900nm to 1000nm, 1000nm to 2000nm, 2000nm to 3000nm, 3000nm to 4000nm, 4000nm to 5000nm, 5000nm to 6000nm, 6000nm to 7000nm, 7000nm to 8000nm, 8000nm to 9000nm, 9000nm to 10µm, 10µm to 100µm, 100µm to 500µm, 500µm to 1mm, 1mm to 2mm, 2mm to 3mm, 3mm to 4mm, 4mm to 5mm, 5mm to 6mm, 6mm to 7mm, 7mm to 8mm, 8mm to 9mm, and 9mm to 10mm. The pore size of each membrane 102 can be in the range of 0.01 angstroms to 10 µm and all ranges and values ​​therebetween, including 0.01 angstroms to 0.1 angstroms, 0.1 angstroms to 1 angstrom, 1 angstrom to 1 nm, 1 nm to 10 nm, 10 nm to 20 nm, 20 nm to 40 nm, 40 nm to 60 nm, 60 nm to 80 nm, 80 nm to 100 nm, 100 nm to 200 nm, 200 nm to 400 nm, 400 nm to 600 nm, 600 nm to 800 nm, 800 nm to 1 µm, 1 µm to 2 µm, 2 µm to 3 µm, 3 µm to 4 µm, 4 µm to 5 µm, 5 µm to 6 µm, 6 µm to 7 µm, 7 µm to 8 µm and 9 µm to 10 µm. In embodiments of the present invention, membrane 102 comprises one or more organic polymer membranes, one or more ceramic membranes, one or more zeolite membranes, one or more mixed membranes, or combinations thereof. Non-limiting examples of organic polymer membranes include chitosan membranes, polyvinyl alcohol (PVA) membranes, polyamide membranes, polyimide membranes, polyacrylonitrile membranes, polyacrylic acid membranes, cellulose acetate membranes, polyblock ether amide membranes, polyurethane membranes, polydimethylsiloxane (PDMS) membranes, and combinations thereof. Non-limiting examples of ceramic membranes include silica membranes, alumina membranes, zirconia membranes, and combinations thereof.Non-limiting examples of zeolite membranes include silica zeolite-1 membranes, ZSM-5 membranes, zeolite NaA membranes, zeolite-Y membranes, and combinations thereof. Hybrid membranes may include membranes containing silica in a polymer matrix (e.g., HYBSI). ® (Netherlands)), polymer-mixed matrix membranes, or combinations thereof. Membrane 102 may include materials from Vito. ® (Belgium) membranes and / or from Alfa Laval ® (American) membrane.

[0031] According to embodiments of the present invention, the organic liquid in the mixture stream 11 of organic liquid and water may contain one or more organic chemicals having one or more hydroxyl groups. In embodiments of the present invention, the organic liquid includes ethanol, glycols, aldehydes, organochlorides, organosulfates, mixtures of bisphenol A (BPA) and phenol, mixtures of acetic acid and hydrochloric acid, methanol-toluene mixtures, toluene, tetrahydrofuran (THF), mixtures of dimethyl carbonate and methanol, or combinations thereof. In embodiments of the present invention, one or more membrane separation modules 100 may form a separation unit for an industrial dehydration process of the organic liquid and water mixture.

[0032] B. Methods for dehydrating mixtures of organic liquids and water

[0033] A method for dehydrating a mixture of organic liquid and water has been discovered. The method may include a pervaporation process for separating water and organic liquid. In the pervaporation process, the upstream of the membrane may be in contact with the liquid mixture feed. When a slight vacuum or purge gas is applied, the component exhibiting an affinity for the membrane (permeate) can become vapor, which diffuses / permeates through the membrane on the permeate side. Due to the low vapor (partial) pressure on the permeate side, the permeate component can be converted into the evaporating phase. The permeate can then be condensed back into a liquid. Pervaporation essentially consists of the steps of evaporation, optionally adsorption and adsorption, permeation and / or diffusion, desorption and evaporation, and then condensation.

[0034] like Figure 2 As shown, embodiments of the present invention include a method 200 for dehydrating a mixture of organic liquid and water. Method 200 may be performed by, for example... Figure 1The separation module 100 shown and described above is implemented. According to an embodiment of the invention, as shown in block 201, method 200 includes feeding a mixture stream 11 of organic liquid and water into the membrane 102 of the separation module 100. In an embodiment of the invention, the mixture stream 11 of organic liquid and water comprises at least 85% by weight of water and at most 15% by weight of organic liquid. As described above, the organic liquid in the mixture stream 11 of organic liquid and water may include ethanol, glycols, aldehydes, organochlorides, organosulfates, mixtures of bisphenol A (BPA) and phenol, mixtures of acetic acid and hydrochloric acid, methanol-toluene mixtures, toluene, tetrahydrofuran (THF), mixtures of dimethyl carbonate and methanol, or combinations thereof. The membrane 102 may include one or more flat sheet membranes, one or more hollow fiber membranes, or combinations thereof.

[0035] In an embodiment of the invention, the feed at frame 201 results in a flux in the membrane of 10 kg∙m⁻¹. -2 ∙hr -1 Up to 40 kg∙m -2 ∙hr -1 Within and between all ranges and values, including 10 kg∙m -2 ∙hr -1 Up to 12kg∙m -2 ∙hr -1 12kg∙m -2 ∙hr -1 Up to 14 kg∙m -2 ∙hr -1 14kg∙m -2 ∙hr -1 Up to 16 kg∙m -2 ∙hr -1 16kg∙m -2 ∙hr -1 Up to 18kg∙m -2 ∙hr -1 18kg∙m -2 ∙hr -1 Up to 20kg∙m -2 ∙hr -1 20kg∙m -2 ∙hr -1 Up to 22kg∙m -2 ∙hr -1 22kg∙m -2 ∙hr -1 Up to 24 kg∙m -2 ∙hr -1 24kg∙m -2 ∙hr -1 Up to 26 kg∙m -2 ∙hr -1 26kg∙m-2 ∙hr -1 Up to 28kg∙m -2 ∙hr -1 28kg∙m -2 ∙hr -1 Up to 30kg∙m -2 ∙hr -1 30kg∙m -2 ∙hr -1 Up to 32kg∙m -2 ∙hr -1 32kg∙m -2 ∙hr -1 Up to 34 kg∙m -2 ∙hr -1 34kg∙m -2 ∙hr -1 Up to 36kg∙m -2 ∙hr -1 36kg∙m -2 ∙hr -1 Up to 38kg∙m -2 ∙hr -1 and 38kg∙m -2 ∙hr -1 Up to 40 kg∙m -2 ∙hr -1 The range. In embodiments of the invention, each membrane separation module 100 comprises 1 to 500 membranes 102 and all ranges and values ​​therebetween, including 1 to 5, 5 to 10 to 15, 15 to 20, 20 to 25, 25 to 30, 30 to 35, 35 to 40, 40 to 45, 45 to 50, 55 to 60, 60 to 65, 65 to 70, 70 to 75, 75 to 80, 80 to 85, 85 to 90, 90 to 95, 95 to 100, 100 to 150, 150 to 200, 200 to 250, 250 to 300, 300 to 350, 350 to 400, 400 to 450, and 450 to 500. The contact surface of each membrane 102 with the mixture flow 11 of organic liquid and water can be 0.001m. 2 Up to 1m 2 The range and all ranges and values ​​within and between, including 0.001m. 2 up to 0.005m 2 0.005m 2 up to 0.01m 2 0.01m 2 up to 0.05m 2 0.05m 2 up to 0.1m 2 0.1m 2 up to 0.2m 2 0.2m2 up to 0.3m 2 0.3m 2 up to 0.4m 2 0.4m 2 up to 0.5m 2 0.5m 2 up to 0.6m 2 0.6m 2 up to 0.7m 2 0.7m 2 up to 0.8m 2 0.8m 2 up to 0.9m 2 0.9m 2 Up to 1m 2 The range. In an embodiment of the invention, at block 201, the mixture flow 11 of organic liquid and water flows at a flow rate of 80 kg / hr to 1200 kg / hr per membrane module 100 and all ranges and values ​​therebetween, including 80 kg / hr to 90 kg / hr, 90 kg / hr to 100 kg / hr, 100 kg / hr to 150 kg / hr, 150 kg / hr to 200 kg / hr, 200 kg / hr to 250 kg / hr, 250 kg / hr to 300 kg / hr, 300 kg / hr to 350 kg / hr, 350 kg / hr to 400 kg / hr, 375 kg / hr to 400 kg / hr, 400 kg / hr to 450 kg / hr. The ranges are: kg / hr, 450 kg / hr to 500 kg / hr, 500 kg / hr to 550 kg / hr, 550 kg / hr to 600 kg / hr, 575 kg / hr to 600 kg / hr, 600 kg / hr to 650 kg / hr, 650 kg / hr to 700 kg / hr, 700 kg / hr to 750 kg / hr, 750 kg / hr to 800 kg / hr, 800 kg / hr to 850 kg / hr, 850 kg / hr to 900 kg / hr, 900 kg / hr to 950 kg / hr, 950 kg / hr to 1000 kg / hr, and 1000 kg / hr to 1200 kg / hr.

[0036] According to an embodiment of the invention, method 200 further includes subjecting the mixture stream 11 of organic liquid and water in membrane 102 to process conditions sufficient to induce pervaporation, as shown in block 202. In an embodiment of the invention, the subjection step at block 202 also induces vapor permeation. In an embodiment of the invention, the process conditions include temperatures in the range of 85°C to 160°C and all ranges and values ​​therebetween, including the ranges of 85°C to 90°C, 90°C to 95°C, 95°C to 100°C, 100°C to 105°C, 105°C to 110°C, 110°C to 115°C, 115°C to 120°C, 120°C to 125°C, 125°C to 130°C, 130°C to 135°C, 135°C to 140°C, 140°C to 145°C, 145°C to 150°C, 150°C to 155°C, and 155°C to 160°C.

[0037] The process conditions at frame 202 may also include feed pressure in the range of 3 bar to 8 bar and all ranges and values ​​therebetween, including the ranges of 3 bar to 3.5 bar, 3.5 bar to 4.0 bar, 4.0 bar to 4.5 bar, 4.5 bar to 5.0 bar, 5.0 bar to 5.5 bar, 5.5 bar to 6.0 bar, 6.0 bar to 6.5 bar, 6.5 bar to 7.0 bar, 7.0 bar to 7.5 bar and 7.5 bar to 8.0 bar. According to an embodiment of the invention, the process conditions at frame 202 may include a vacuum on the permeate side of membrane 102 in the range of 20 mbar to 250 mbar and all ranges and values ​​therebetween, including 20 mbar to 30 mbar, 30 mbar to 40 mbar, 40 mbar to 50 mbar, 50 mbar to 60 mbar, 60 mbar to 70 mbar, 70 mbar to 80 mbar, 80 mbar to 90 mbar, 90 mbar to 100 mbar, 100 mbar to 110 mbar, 110 mbar to 1... The ranges are 20 mbar, 120 mbar to 130 mbar, 130 mbar to 140 mbar, 140 mbar to 150 mbar, 150 mbar to 160 mbar, 160 mbar to 170 mbar, 170 mbar to 180 mbar, 180 mbar to 190 mbar, 190 mbar to 200 mbar, 200 mbar to 210 mbar, 210 mbar to 220 mbar, 220 mbar to 230 mbar, 230 mbar to 240 mbar, and 240 mbar to 250 mbar.

[0038] In an embodiment of the invention, method 200 may include soaking membrane 102 in an immersion solution prior to the undergoing step at block 202. In an embodiment, the immersion solution comprises 25% to 30% by weight of the organic component of a mixture stream 11 of organic liquid and water, within all ranges and values ​​therebetween, including 26%, 27%, 28%, and 29% by weight. The immersion solution may also comprise 70% to 75% by weight of water, within all ranges and values ​​therebetween, including 71%, 72%, 73%, and 74% by weight. The immersion solution may also comprise about 50 ppm of acetaldehyde and / or about 50 ppm of acetic acid. According to an embodiment of the invention, the immersion of membrane 102 is carried out at a temperature of 100°C to 125°C, including all ranges and values ​​therebetween, including 100°C to 102°C, 102°C to 104°C, 104°C to 106°C, 106°C to 108°C, 108°C to 110°C, 110°C to 112°C, 112°C to 114°C, 114°C to 116°C, 116°C to 118°C, 118°C to 120°C, 120°C to 122°C, 122°C to 124°C, and 124°C to 125°C. The immersion of the membrane can be carried out for a duration of 3 hours to 3.5 hours, including all ranges and values ​​therebetween, including 3.1 hours, 3.2 hours, 3.3 hours, and 3.4 hours.

[0039] According to an embodiment of the invention, as shown in block 203, method 200 further includes recovering permeate of permeate stream 12 containing a higher weight percentage (wt%) of water than the water in the organic liquid and water mixture stream 11, and permeate of permeate stream 13 containing a higher weight percentage (wt%) of organic liquid than the organic liquid in the organic liquid and water mixture stream 11. In an embodiment of the invention, permeate stream 12 contains 90 wt% to 99.9 wt% water, including all ranges and values ​​therebetween, including 90 wt% to 90.5 wt%, 90.5 wt% to 91.0 wt%, 91.0 wt% to 91.5 wt%, 91.5 wt% to 92.0 wt%, 92.0 wt% to 92.5 wt%, 92.5 wt% to 93.0 wt%, 93.0 wt% to 93.5 wt%, 93.5 wt% to 94.0 wt%, 94.0 wt% to 94.9 wt%. The range is 0.5% by weight, 94.5% by weight to 95.0% by weight, 95.0% by weight to 95.5% by weight, 95.5% by weight to 96.0% by weight, 96.0% by weight to 96.5% by weight, 96.5% by weight to 97.0% by weight, 97.0% by weight to 97.5% by weight, 97.5% by weight to 98.0% by weight, 98.0% by weight to 98.5% by weight, 98.5% by weight to 99.0% by weight, 99.0% by weight to 99.5% by weight, and 99.5% by weight to 99.9% by weight. In an embodiment, the permeate stream 13 comprises 20 wt% to 99 wt% organic liquid, including all ranges and values ​​therebetween, including 20 wt% to 25 wt%, 25 wt% to 30 wt%, 30 wt% to 35 wt%, 35 wt% to 40 wt%, 40 wt% to 45 wt%, 45 wt% to 50 wt%, 50 wt% to 55 wt%, 55 wt% to 60 wt%, 60 wt% to 65 wt%, 65 wt% to 70 wt%, 70 wt% to 75 wt%, 75 wt% to 80 wt%, 80 wt% to 85 wt%, 85 wt% to 90 wt%, 90 wt% to 95 wt%, and 95 wt% to 99 wt%. In an embodiment of the invention, recovery at block 203 includes cooling, second-stage membrane recovery, extraction, separator distillation, reactive distillation, electrochemical processes, crystallization, adsorption, stripping, or combinations thereof.

[0040] In an embodiment of the invention, the separation module 100 can be used for vapor permeation without causing the liquid in the membrane to evaporate. In the vapor permeation process without causing the liquid in the membrane to evaporate, the feed stream is in vapor form when it comes into contact with the membrane of the separation module 100.

[0041] Although it has been referenced Figure 2 The boxes described embodiments of the invention, but it should be understood that the operation of the invention is not limited to these. Figure 2 The specific boxes and / or the specific order of the boxes are illustrated in the diagram. Accordingly, embodiments of the invention can be related to... Figure 2 Different sequences use various boxes to provide the functionality described in this article.

[0042] As part of the disclosure of this invention, the following specific embodiments are included. These embodiments are for illustrative purposes only and are not intended to limit the invention. Those skilled in the art will readily recognize that parameters can be changed or modified to produce substantially the same results. Pervatech is used in a pilot-scale pervaporation unit. ® The membrane dehydrates a mixture of monoethylene glycol and water. The membrane comprises silica in a polymer matrix and a mixed silica (Hybsi) sourced from ECN. ® Polymer-mixed matrix membranes, PDMS, and polyetherimide. Other materials that can be used include PVA, chitosan, polyamide, polyimide, PAN, polyacrylic acid, cellulose acetate, PDMS, polyblock ether amide, polyurethane, ceramics, silica, alumina, zirconium oxide, hydrophilic zeolite membranes (zeolite NaA, Y) or hydrophobic zeolite membranes (silica zeolite-1, ZSM-5).

[0043] Example

[0044] Example 1

[0045] (Pervaporation experiment for separating monoethylene glycol on a pilot scale)

[0046] Pervatech was used in a pilot-scale pervaporation unit. ® The membrane is used for dehydration of a mixture of monoethylene glycol and water. Each module in the pilot plant contains 10 membrane tubes. Each membrane tube has an outer diameter of 10.04 mm and an inner diameter of 6.5 mm. The wall thickness of each membrane tube is 1.89 mm. The contact area of ​​each membrane tube is approximately 46.9 cm². 2 The film comprises silica in a polymer matrix and a mixed silica (Hybsi) from ECN. ® A polymer-mixed matrix membrane, PDMS, or polyetherimide was used. The feed concentration of monoethylene glycol ranged from 10% to 80% by weight. The flow rate was fixed at 100 L / hr. The feed temperature ranged from 60°C to 120°C. The feed pressure was set between 1 bar and 5 bar. The vacuum on the permeate side of the membrane was approximately 70 mbar. Cooling water for permeate recovery was maintained at approximately 5°C. Results showed that the optimal conditions for pervaporation included a feed temperature of 120°C, a feed pressure of approximately 5 bar, a flow rate of 100 L / hr, and a flow rate of 12.5 kg∙m⁻². -2 ∙hr -1 The flux was measured. Further tests were conducted, and the results are shown in Table 1.

[0047] Table 1. Results of dehydration of a mixture of monoethylene glycol and water

[0048]

[0049] Example 2

[0050] (Dehydration simulation of a mixture of monoethylene glycol and water)

[0051] In Aspen Plus ® A mixing model was established in the platform to simulate the separation of a mixture of monoethylene glycol and water via pervaporation. This mixing model uses parameters from both a solution-diffusion model and a pore flow model to calculate the permeate flux. No assumptions were made regarding the state of the components within the membrane phase.

[0052] To determine the state of the components in the membrane phase, the model assumes that the components exist as an imaginary phase. When the pressure of the imaginary phase exceeds the saturation pressure of the diffusing component, it is in a liquid state. When the pressure of the imaginary phase is less than the saturation pressure, it is in a vapor state. When the membrane phase is liquid, the flux and concentration in the membrane phase are assumed to follow a solution-diffusion model. Furthermore, in the membrane phase corresponding to the liquid segment, the diffusivity is independent of concentration. In the vapor segment, the diffusivity is assumed to increase exponentially with concentration. Table 2 shows the simulation results for the dehydration of a mixture of monoethylene glycol and water.

[0053] Table 2. Simulation results of dehydration of a mixture of monoethylene glycol and water

[0054]

[0055] Example 3

[0056] (Pervaporation experiment for separating monoethylene glycol on a pilot scale)

[0057] Pervatech was used in a pilot-scale pervaporation unit. ® Acid-resistant HybSi membranes are used for the dehydration of mixtures of monoethylene glycol and water. Each module in this pilot plant contains eight membrane tubes arranged in series. Each membrane tube has an outer diameter of 10.04 mm and an inner diameter of 6.5 mm. The wall thickness of each membrane tube is 1.89 mm. The contact area of ​​each membrane tube is approximately 46.9 cm². 2The membrane was the same as in Example 1. The feed concentration of monoethylene glycol ranged from 4.2 wt% to 18.2 wt%. Flow rates were 200 L / hr, 375 L / hr, 575 L / hr, and 1200 L / hr, respectively. Feed temperatures ranged from 122°C to 155°C. Feed pressures were set between 2.5 bar and 6 bar. Vacuum on the permeate side of the membrane ranged from 50 mbar to 300 mbar. Cooling water for permeate recovery was at approximately 5°C. Results showed improvements were achieved due to 1) a decrease in the glycol feed concentration and 2) an increase in the feed temperature. The separation can be scaled up and has been shown to achieve higher flow rates. All data results in the table are provided for the separation obtained for each single tube. Additional data are provided in Table 3 below.

[0058] Table 3. Results of dehydration of a mixture of monoethylene glycol and water

[0059]

[0060] Table 4. Tube dimensions of Example 3

[0061]

[0062] Example 4

[0063] Further simulations were performed according to Example 3. The results are shown in Table 5 below.

[0064] Table 5. Simulation results of dehydration of a mixture of monoethylene glycol and water

[0065]

[0066] In the context of this invention, at least 18 embodiments are disclosed. Embodiment 1 is a method for dehydrating a mixture of an organic liquid and water. The method includes feeding the mixture into a membrane, wherein the mixture contains at least 85% by weight of water and at most 15% by weight of an organic liquid. The method further includes subjecting the mixture in the membrane to process conditions sufficient to cause pervaporation, wherein the process conditions include a temperature in the range of 85°C to 160°C. Additionally, the method includes recovering a permeate containing a weight percentage of water greater than the weight percentage of water in the mixture and a residue containing a weight percentage of organic liquid greater than the weight percentage of organic liquid in the mixture. Embodiment 2 is the method of Embodiment 1, wherein the process conditions in the subjecting step include a feed pressure in the range of 3 bar to 8 bar. Embodiment 3 is the method of Embodiment 1 or 2, wherein the subjecting step also causes vapor permeation. Embodiment 4 is the method of any one of Embodiments 1 to 3, wherein the organic liquid contains an organic compound having one or more hydroxyl groups. Embodiment 5 is the method of Embodiment 4, wherein the organic liquid comprises BPA-phenol, THF-methanol, acetic acid-HCl, toluene, DMC-methanol, methanol-toluene, ethanol, diol, polyol, triol, or combinations thereof. Embodiment 6 is the method of any one of Embodiments 1 to 5, wherein the membrane comprises a flat sheet membrane and / or a hollow fiber membrane. Embodiment 7 is the method of Embodiment 6, wherein the flat sheet membrane comprises a membrane suitable for nanofiltration, ultrafiltration, reverse osmosis, pervaporation, vapor permeation, or combinations thereof. Embodiment 8 is the method of any one of Embodiments 6 or 7, wherein the flat sheet membrane is selected from polysulfonamide on polysulfone, polyacrylonitrile, polydimethylsiloxane, and combinations thereof. Embodiment 9 is the method of any one of Embodiments 6 to 8, wherein the flat sheet membrane is configured as a plate-frame structure, a series-parallel network structure, a core-shell structure, or combinations thereof. Embodiment 10 is the method of any one of Embodiments 6 to 9, wherein the hollow fiber membrane is selected from hybrid silica membranes, zeolite membranes, hybrid ceramic membranes, organic polymer membranes, and combinations thereof. Embodiment 11 is a method of any one of embodiments 1 to 10, wherein the process conditions include a mixture flow rate of 80 kg / hr to 1000 kg / hr per membrane module. Embodiment 12 is a method of any one of embodiments 1 to 11, wherein the process conditions include a vacuum pressure on the permeate side of the membrane in the range of 20 mbar to 250 mbar. Embodiment 13 is a method of any one of embodiments 1 to 12, wherein the method further includes soaking the membrane in an soaking liquid prior to the step, the soaking liquid comprising 25% to 30% by weight of the organic component of the mixture, 70% to 75% by weight of water, about 50 ppm of acetaldehyde, and about 50 ppm of acetic acid. Embodiment 14 is a method of embodiment 13, wherein the membrane soaking is performed at a temperature of 100°C to 125°C for 3 to 3.5 hours.Implementation scheme 15 is a method of any one of implementation schemes 1 to 14, wherein the flux of the membrane is 10 kg∙m. -2 ∙hr -1 Up to 40 kg∙m -2 ∙hr -1 Within the range of... Embodiment 16 is the method of any one of embodiments 1 to 15, wherein the permeate contains 90.0% to 99.9% by weight of water. Embodiment 17 is the method of any one of embodiments 16, wherein the permeate contains 20% to 99% by weight of organic liquid. Embodiment 18 is the method of any one of embodiments 1 to 17, wherein the thickness of the membrane is in the range of 10 nm to 1 mm.

[0067] While the embodiments and advantages of this application have been described in detail, it should be understood that various changes, substitutions, and modifications may be made herein without departing from the spirit and scope of the embodiments, which are defined by the appended claims. Furthermore, the scope of this application is not intended to be limited to the specific embodiments of the processes, machines, manufactures, compositions of matter, means, methods, and steps described in the specification. From the foregoing disclosure, those skilled in the art will readily understand that existing or later-developed processes, machines, manufactures, compositions of matter, means, methods, or steps can perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein. Accordingly, the appended claims are intended to include such processes, machines, manufactures, compositions of matter, means, methods, or steps within their scope.

Claims

1. A method for dehydrating a mixture of an organic liquid and water, the method comprising: The mixture is fed into a membrane, wherein the mixture contains at least 85% by weight water and at most 15% by weight organic liquid; The mixture in the membrane is subjected to process conditions sufficient to cause pervaporation, wherein the process conditions include temperatures from 85°C to 160°C. The permeate contains water at a weight percentage higher than the weight percentage of water in the mixture, and the residue contains organic liquid at a weight percentage higher than the weight percentage of organic liquid in the mixture.

2. The method of claim 1, wherein the process conditions subjected to the step include a feed pressure of 3 to 8 bar.

3. The method according to any one of claims 1 to 2, wherein the step further causes vapor permeation.

4. The method according to any one of claims 1 to 2, wherein the organic liquid comprises an organic compound having one or more hydroxyl groups.

5. The method according to claim 4, wherein the organic liquid comprises BPA-phenol, THF-methanol, acetic acid-HCl, toluene, DMC-methanol, methanol-toluene, ethanol, diol, polyol, triol, or a combination thereof.

6. The method according to any one of claims 1 to 2, wherein the membrane comprises a flat sheet membrane and / or a hollow fiber membrane.

7. The method of claim 6, wherein the flat sheet membrane comprises a membrane suitable for nanofiltration, ultrafiltration, reverse osmosis, pervaporation, vapor permeation, or a combination thereof.

8. The method of claim 6, wherein the flat sheet membrane is selected from polysulfonamide, polyacrylonitrile, polydimethylsiloxane, and combinations thereof.

9. The method of claim 6, wherein the flat sheet membrane is configured as a plate-frame structure, a series-parallel network structure, a core-shell structure, or a combination thereof.

10. The method according to claim 6, wherein the hollow fiber membrane is selected from hybrid silica membranes, zeolite membranes, hybrid ceramic membranes, organic polymer membranes, and combinations thereof.

11. The method according to any one of claims 1 to 2, wherein the process conditions include a mixture flow rate of 80 kg / hr to 1000 kg / hr per membrane module.

12. The method according to any one of claims 1 to 2, wherein the process conditions include a vacuum pressure of 20 mbar to 250 mbar on the permeate side of the membrane.

13. The method according to any one of claims 1 to 2, further comprising soaking the membrane in an soaking liquid prior to undergoing the step, said soaking liquid comprising 25% to 30% by weight of an organic component of a mixture, 70% to 75% by weight of water, about 50 ppm of acetaldehyde and about 50 ppm of acetic acid.

14. The method according to claim 13, wherein the immersion of the membrane is carried out at a temperature of 100°C to 125°C for 3 to 3.5 hours.

15. The method according to any one of claims 1 to 2, wherein the membrane flux is 10 kg∙m³. -2 ∙hr -1 Up to 40 kg∙m -2 ∙hr -1 .

16. The method according to any one of claims 1 to 2, wherein the permeate comprises 90.0% to 99.9% by weight of water.

17. The method according to any one of claims 1 to 2, wherein the residue comprises 20% by weight to 99% by weight of organic liquid.

18. The method according to any one of claims 1 to 2, wherein the thickness of the film is from 10 nm to 1 mm.

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