Patent Description:
The present invention generally relates to liquid separation technologies. More specifically, the present invention relates to systems and methods for separating a water and organic liquid mixture using pervaporation processes.

Separation of liquid mixtures is an important process in the chemical industry for purifying products and/or recovering unreacted materials. Conventionally, distillation has been the most widely used technique for separating liquid components. However, several drawbacks, including high energy demand, large steam consumption, and low separation efficiency per pass, limit the economic viability of distillation.

Separation of water and organic compounds such as diols, alcohols, and polyols generally requires an extremely large amount of energy. Because of formation of azeotropes, the high heat capacity of water, and/or close boiling point range between water and the organic compounds, multi-stage distillation that involves a series of distillation columns with high reflux rate is often employed. Therefore, both capital expenditure and operational costs for distillation of water-organic compound mixtures are generally high. Other techniques such as reverse osmosis, ultrafiltration, and nanofiltration have been explored as alternatives for separating water and organic compounds. However, upscaling of these techniques to a commercial-scale process has been technically challenging due to factors such as low separation factor, low flux, and/or loss of products.

Overall, while systems and methods for separating water and organic compounds exist, the need for improvements in this field persists in light of at least the aforementioned drawbacks for the conventional methods.

A solution to at least some of the above-mentioned problems associated with the conventional methods for separating water and organic compounds has been discovered. The solution resides in a method of dehydrating a mixture of organic liquid and water using a membrane under process conditions sufficient to cause pervaporation. This can be beneficial for at least reducing the energy consumption and capital expenditure required for separating the organic liquid and water compared to distillation. Notably, the method is capable of achieving a high membrane flux level, resulting in a low requirement for membrane surface area. Furthermore, the method is carried out such that the membrane has a high separation factor for water and organic liquid including diol, alcohol, and/or polydiols, resulting in reduced loss of product. Moreover, the method of the present invention is more scalable to a commercial-scale process than 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 the currently available methods for separating water and organic liquid.

Embodiments of the invention include a method of dehydrating a mixture of organic liquid and water. The method comprises feeding the mixture to a membrane. The mixture comprises a minimum of <NUM> wt. % water and a maximum of <NUM> wt. % organic liquid. The method further comprises subjecting the mixture in the membrane to process conditions sufficient to cause pervaporation. The process conditions comprise a temperature in a range of <NUM> to <NUM>. The method further comprises recovering a permeate comprising a higher wt. % of water than the wt. % of water in the mixture and a retentate comprising a higher wt. % of organic liquid than the wt. % of the organic liquid in the mixture.

Embodiments of the invention include a method of dehydrating a mixture of organic liquid and water. The method comprises feeding the mixture to a membrane. The mixture comprises a minimum of <NUM> wt. % water and a maximum of <NUM> wt. % organic liquid. The method further comprises subjecting the mixture in the membrane to process conditions sufficient to cause pervaporation. The process conditions comprise a temperature in a range of <NUM> to <NUM> and a pressure in a range of <NUM> to <NUM> bar. The method further comprises recovering a permeate comprising a higher wt. % of water than the wt. % of water in the mixture and a retentate comprising a higher wt. % of organic liquid than the wt. % of the organic liquid in the mixture.

Embodiments of the invention include a method of dehydrating a mixture of glycol and water. The method comprises feeding the mixture to a membrane. The mixture comprises a minimum of <NUM> wt. % water and a maximum of <NUM> wt. % organic liquid. The method further comprises subjecting the mixture in the membrane to process conditions sufficient to cause pervaporation. The process conditions comprise a temperature in a range of <NUM> to <NUM> and a pressure in a range of <NUM> to <NUM> bar. The method further comprises recovering a permeate comprising a higher wt. % of water than the wt. % of water in the mixture and a retentate comprising a higher wt. % of organic liquid than the wt. % of the organic liquid in the mixture.

The terms "wt. %" or "mol. %" refers to a weight, volume, or molar percentage of a component, respectively, based on the total weight, the total volume, or the total moles of material that includes the component. In a non-limiting example, <NUM> moles of component in <NUM> moles of the material is <NUM> mol. % of component.

The terms "inhibiting" or "reducing" or "preventing" or "avoiding" or any variation of these terms, when used in the claims and/or the specification, includes any measurable decrease or complete inhibition to achieve a desired result.

The term "pervaporation," as that term is used in the specification and/or claims, means a process for separation of a liquid mixture by partial vaporization of the mixture through a membrane. Pervaporation combines permeation and vaporization.

The term "primarily," as that term is used in the specification and/or claims, means greater than any of <NUM> wt. %, <NUM> mol. %, and <NUM> vol. For example, "primarily" may include <NUM> wt. % to <NUM> wt. % and all values and ranges there between, <NUM> mol. % to <NUM> mol. % and all values and ranges there between, or <NUM> vol. % to <NUM> vol. % and all values and ranges there between.

Other objects, features and advantages of the present invention will become apparent from the following figures, detailed description, and examples. It should be understood, however, that the figures, detailed description, and examples, while indicating specific embodiments of the invention, are given by way of illustration only and are not meant to be limiting.

Currently, distillation is used for separating organic liquid and water when purifying organic liquid. Additionally, organic liquid and water can also be separated using reverse osmosis, ultrafiltration, and/or nanofiltration on a limited scale. However, these existing methods have several problems. Distillation of mixtures of organic liquid and water generally consumes a large amount of energy and requires multiple distillation columns in series due to the formation azeotropes between water and the organic liquid. Thus, the operational costs can be high when distillation is used for separating mixtures of organic liquid and water. Reverse osmosis, ultrafiltration, and/or nanofiltration require less energy than distillation. However, using these methods in an industrial scale is challenging because of the limited separation factors (SF), and requirement of large membrane surfaces. The present invention provides a solution to these problems. The solution is premised on a method of dehydrating a mixture of organic liquid and water. The method involves separating water from organic liquid using one or more membranes via pervaporation. This method requires less energy than distillation. Furthermore, the capital expenditure for using this method is lower than distillation, which requires a series of distillation columns. Additionally, compared to conventional reverse osmosis, ultrafiltration, and/or nanofiltration, this method is capable of improving separation efficiency of the membranes and increasing flux per unit area of membranes, resulting in scalability to commercial production. These and other non-limiting aspects of the present invention are discussed in further detail in the following sections.

In embodiments of the invention, the pervaporation system used for separating mixture of organic liquid and water can include one or more membrane modules. With reference to <FIG>, a schematic diagram is shown for membrane separation module <NUM> that is capable of separating organic liquid from water with reduced energy consumption and high separation efficiency compared to conventional systems for separating a mixture of organic liquid and water. According to embodiments of the invention, membrane separation module <NUM> comprises a frame-and-plate structure, a tubular type module, a series-parallel network structure, a core-shell structure, a hollow fiber structure, or combinations thereof.

According to embodiments of the invention, membrane separation module <NUM> may comprise frame <NUM>. In embodiments of the invention, frame <NUM> is adapted to contain one or more membranes <NUM>. According to embodiments of the invention, frame <NUM> is further adapted to receive mixture of organic liquid and water stream <NUM> therein and release permeate stream <NUM> and/or retentate stream <NUM> therefrom. In embodiments of the invention, permeate stream <NUM> may be released downstream of membrane(s) <NUM>. Retentate stream <NUM> may be released upstream of membrane(s) <NUM>. In embodiments of the invention, permeate stream <NUM> comprises primarily water. Retentate stream <NUM> may comprise primarily the organic liquid. According to embodiments of the invention, membrane separation module <NUM> further comprises support <NUM> disposed against membrane <NUM>. Support <NUM> may be adapted to support membrane <NUM> so that membrane(s) <NUM> stays stationary. In embodiments, support <NUM> is disposed at a side of membrane <NUM> distal from mixture of organic liquid and water stream <NUM>. Non-limiting examples of support <NUM> may include polyvinyl alcohol, polysulfone, silica, polyimide, zeolite, and combinations thereof.

In embodiments of the invention, membrane(s) <NUM> is adapted to allow vapor of the organic liquid to pass through and substantially stop water from passing through. Membrane(s) <NUM> may include one or more flat sheet membranes, one or more hollow fiber membranes, or a combination thereof. According to embodiments of the invention, each membrane <NUM> has a thickness of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>. Each membrane <NUM> may have a pore size in a range of <NUM> angstrom to <NUM> and all ranges and values there between including the ranges of <NUM> to <NUM> angstrom, <NUM> to <NUM> angstrom, <NUM> angstrom to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. In embodiments of the invention, membrane(s) <NUM> comprise one or more organic polymeric membranes, one or more ceramic membranes, one or more zeolite membranes, one or more hybrid membranes, or combinations thereof. Non-limiting examples of organic polymeric membranes include chitosan membranes, polyvinyl alcohol (PVA) membranes, polyamides membranes, polyimides membranes, polyacrylonitrile membranes, polyacrylic acid membranes, cellulose acetate membranes, poly-block-ether-amide membranes, polyurethane membranes, polydimethyl siloxane (PDMS) membranes, and combinations thereof. Non-limiting examples for ceramic membranes include silica membranes, alumina membranes, zirconia membranes, and combinations thereof. Non-limiting examples for zeolite membranes include silicalite-<NUM> membranes, ZSM-<NUM> membranes, zeolite NaA membranes, zeolite-Y membranes, and combinations thereof. Hybrid membranes may include membranes comprising silica in polymeric matrix (e.g., HYBSI® membrane, Netherlands), polymeric mixed matrix membranes, or combinations thereof. Membrane(s) <NUM> may include a membrane from Vito® (Belgium), and/or a membrane from Alfa Laval® (USA).

According to embodiments of the invention, the organic liquid in mixture of organic liquid and water stream <NUM> may include one or more organic chemicals having one or more hydroxyl groups. In embodiments of the invention, the organic liquid includes alcohol, diol, aldehydes, organic chlorides, organic sulphates, a bisphenol A (BPA) and phenol mixture, an acetic acid and hydrochloric acid mixture, a methanol-toluene mixture, toluene, tetrahydrofuran (THF), a dimethyl carbonate and methanol mixture, or combinations thereof. In embodiments of the invention, one or more membrane separation modules <NUM> can form a separation unit that is used in an industrial dehydration process for mixtures of organic liquid and water.

Methods of dehydrating a mixture of organic liquid and water have been discovered. The methods may include a pervaporation process to separate water and the organic liquid. In a pervaporation process, upstream of the membrane can be in contact with a liquid mixture feed. The component that displays affinity to the membrane (the permeate) can be turned into vapor, which diffuses/permeates through the membrane on the permeate side when slight vacuum or sweeping gas is applied. The permeate component can be converted into an evaporation phase due to the low (partial) vapor pressure on the permeate side. The permeate may be re-condensed to a liquid. Pervaporation essentially can consist of the steps of vaporization, optionally sorption and adsorption, permeation and/or diffusion, desorption and vaporization followed by re-condensation.

As shown in <FIG>, embodiments of the invention include method <NUM> for dehydrating a mixture of organic liquid and water. Method <NUM> may be implemented by separation module <NUM>, as shown in <FIG> and described above. According to embodiments of the invention, as shown in block <NUM>, method <NUM> comprises feeding mixture of organic liquid and water stream <NUM> to membrane(s) <NUM> of separation module <NUM>. In embodiments of the invention, mixture of organic liquid and water stream <NUM> comprises a minimum of <NUM> wt. % water and a maximum of <NUM> wt. % organic liquid. As described above, the organic liquid in mixture of organic liquid and water stream <NUM> may include alcohol, diol, aldehydes, organic chlorides, organic sulphates, a bisphenol A (BPA) and phenol mixture, an acetic acid and hydrochloric acid mixture, a methanol-toluene mixture, toluene, tetrahydrofuran (THF), a dimethyl carbonate and methanol mixture, or combinations thereof. Membrane(s) <NUM> may include one or more flat sheet membranes, one or more hollow fiber membranes, or a combination thereof.

In embodiments of the invention, the feeding at block <NUM> results in a flux in membrane(s) in a range of <NUM> to <NUM>·m-<NUM>·hr-<NUM> and all ranges and values there between including ranges of <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>·hr-<NUM>, <NUM> to <NUM>·m-<NUM>-hr-<NUM>, and <NUM> to <NUM>·m-<NUM>·hr-<NUM>. In embodiments of the invention, each membrane separation module <NUM> comprises <NUM> to <NUM> membranes <NUM> and all ranges and values there between including <NUM> to <NUM>, <NUM> to <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. Each of membrane <NUM> may comprise a contacting surface with mixture of organic liquid and water stream <NUM> in a range of <NUM> to <NUM><NUM> and all ranges and values there between including ranges of <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>, <NUM> to <NUM><NUM>. In embodiments of the invention, at block <NUM>, mixture of organic liquid and water stream <NUM> is flowed at a flow rate of <NUM> to <NUM>/hr per membrane module <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, <NUM> to <NUM>/hr, and <NUM> to <NUM>/hr and <NUM> to <NUM>/hr.

According to embodiments of the invention, method <NUM> further comprises subjecting the mixture of organic liquid and water stream <NUM> in membrane <NUM> to process conditions sufficient to cause pervaporation, as shown in block <NUM>. In embodiments of the invention, the subjecting step at block <NUM> further causes vapor permeation. In embodiments of the invention, the process conditions comprise a temperature in the range of <NUM> to <NUM> and all ranges and values there between including ranges of <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>.

The process conditions at block <NUM> may further include a feed pressure of in a range of <NUM> to <NUM> bar and all ranges and values there between including ranges of <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, <NUM> to <NUM> bar, and <NUM> to <NUM> bar. According to embodiments of the invention, process conditions at block <NUM> can include a vacuum on a permeate side of membrane <NUM> in a range of <NUM> to <NUM> mbar and all ranges and values there between including ranges of <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, <NUM> to <NUM> mbar, and <NUM> to <NUM> mbar.

According to the invention, method <NUM> includes, prior to subjecting at block <NUM>, soaking membrane <NUM> with a soaking liquid. In embodiments, the soaking liquid comprises <NUM> to <NUM> wt. % organic components of mixture of organic liquid and water stream <NUM> and all ranges and values there between including <NUM> wt. %, <NUM> wt. %, <NUM> wt. %, and <NUM> wt. The soaking liquid may further include <NUM> to <NUM> wt. % water and all ranges and values there between including <NUM> wt. %, <NUM> wt. %, <NUM> wt. %, and <NUM> wt. The soaking liquid may further include about <NUM> ppm acetaldehyde and/or about <NUM> ppm acetic acid. According to embodiments of the invention, the soaking of membrane <NUM> is carried out at a temperature of <NUM> to <NUM>, including all ranges and values there between including <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, <NUM> to <NUM>, and <NUM> to <NUM>. The soaking of membrane may be carried out for a duration of <NUM> to <NUM> hours, including all ranges and values there between including <NUM> hours, <NUM> hours, <NUM> hours, and <NUM> hours.

According to embodiments of the invention, as shown in block <NUM>, method <NUM> further comprises recovering a permeate of permeate stream <NUM> comprising a higher weight percentage (wt. %) of water than the weight percentage (wt. %) of water in mixture of organic liquid and water stream <NUM>, and a retentate of retentate stream <NUM> comprising a higher weight percentage (wt. %) of organic liquid than the weight percentage (wt. %) of the organic liquid in mixture of organic liquid and water stream <NUM>. In embodiments of the invention, permeate stream <NUM> comprises <NUM> to <NUM> wt. % water, including all ranges and values there between, including ranges of <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, and <NUM> to <NUM> wt. In embodiments, retentate stream <NUM> comprises <NUM> to <NUM> wt. % of the organic liquid, including all ranges and values there between including ranges of <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. %, <NUM> to <NUM> wt. In embodiments of the invention, recovering at block <NUM> comprises cooling, a second stage membrane recovering, extraction, divided wall distillation, reactive distillation, electrochemical processes, crystallization, adsorption, stripping, or combinations thereof.

In embodiments of the invention, separation module <NUM> can be used for vapor permeation without vaporization of liquid in the membrane(s). In a vapor permeation process without vaporization of liquid in the membrane(s), the feed stream is in vapor form when it comes in contact with the membrane(s) of separation module <NUM>.

Although embodiments of the present invention have been described with reference to blocks of <FIG>, it should be appreciated that operation of the present invention is not limited to the particular blocks and/or the particular order of the blocks illustrated in <FIG>. Accordingly, embodiments of the invention may provide functionality as described herein using various blocks in a sequence different than that of <FIG>.

As part of the disclosure of the present invention, specific examples are included below. The examples are for illustrative purposes only and are not intended to limit the invention. Those of ordinary skill in the art will readily recognize parameters that can be changed or modified to yield essentially the same results. Dehydration of monoethylene glycol and water mixture was performed using a Pervatech® membrane in a pilot pervaporation plant. The membrane comprises silica in polymeric matrix, Hybrid Silica Hybsi® from ECN, polymeric mixed matrix membrane, PDMS and polyetherimide. Other materials, which can be used, include PVA, chitosan, polyamides, polyimides, PAN, polyacrylic acid, cellulose acetate, PDMS, poly-block-ether-amides, polyurethanes, ceramic, silica, alumina, zirconia, zeolite membranes, hydrophilic (zeolite NaA, Y) or hydrophobic (silicalite-<NUM>, ZSM-<NUM>).

Dehydration of monoethylene glycol and water mixture was performed using a Pervatech® membrane in a pilot pervaporation plant. Each module in the pilot plant included <NUM> membrane tubes. Each membrane tube had an outer diameter of <NUM> and inner diameter of <NUM>. The wall thickness for each membrane tube was <NUM>. The contacting area of each membrane tube was about <NUM><NUM>. The membrane comprises silica in polymeric matrix, Hybrid Silica Hybsi® from ECN, polymeric mixed matrix membrane, PDMS, or polyetherimide. The feed concentration of monoethylene glycol was in a range of <NUM> to <NUM> wt. The flowrate was fixed at <NUM>/hr. The feed temperature was in a range of <NUM> to <NUM>. The feed pressure was set in a range of <NUM>-<NUM> bar. The vacuum on the permeate side of the membrane was about <NUM> mbar. Cooling water used for recovering the permeate was at about <NUM>. The results indicate that the optimized conditions for pervaporation include a feed temperature of <NUM>, a feed pressure of about <NUM> bar, a flow rate of <NUM>/hr, and a flux of <NUM>·m-<NUM>·hr-<NUM>. Further tests were also done and the results are shown in Table <NUM>.

A hybrid model was built in Aspen Plus® platform to simulate the separation of monoethylene glycol and water mixture via pervaporation. The hybrid model used parameters of both the solution-diffusion model and the pore flow model to calculate the permeate flux. No presumption was made about the state of the components within the membrane phase.

In order to determine the state of the components in the membrane phase, in the model, the components in the membrane were assumed to exist in an imaginary phase. When the pressure of the imaginary phase exceeded the saturation pressure of the diffusing components, it was in liquid state. The imaginary phase was in vapor state when the imaginary phase had a pressure less than the saturation pressure. The flux and concentration in the membrane phase was considered to follow the solution-diffusion model when it was liquid. Furthermore, in the membrane phase corresponding to the liquid section, the diffusivity is independent of concentration. Whereas, in the vapor section, the diffusivity was considered to be increasing exponentially with concentration. The results for the simulations on dehydration of a mixture of monoethylene glycol and water are shown in Table <NUM>.

Dehydration of monoethylene glycol and water mixture was performed using a Pervatech® Acid Resistant HybSi membrane in a pilot pervaporation plant. Each module in the pilot plant included <NUM> membrane tubes arranged in series-configuration. Each membrane tube had an outer diameter of <NUM> and inner diameter of <NUM>. The wall thickness for each membrane tube was <NUM>. The contacting area of each membrane tube was about <NUM><NUM>. The membrane was the same as in Example <NUM>. The feed concentration of monoethylene glycol was in a range of <NUM> to <NUM> wt. The flowrate was varied at <NUM>, <NUM>, <NUM> and <NUM>/hr. The feed temperature was in a range of <NUM> to <NUM>. The feed pressure was set in a range of <NUM> to <NUM> bar. The vacuum on the permeate side of the membrane ranged between <NUM> to <NUM> mbar. Cooling water used for recovering the permeate was at about <NUM>. The results indicate improvement as <NUM>) the glycol feed concentration in feed reduced and <NUM>) the temperature of the feed increased. The separation can be scaled up and has been demonstrated to larger flow rates. All data results in tables are provided for separation obtained per single tube. Additional data is provided in Table <NUM> below.

Additional simulations were conducted in accordance with Example <NUM>.

Claim 1:
A method of dehydrating a mixture of organic liquid and water, the method comprising:
feeding the mixture to a membrane (<NUM>) of a membrane separation module, wherein the mixture comprises a minimum of <NUM> wt. % water and a maximum of <NUM> wt. % organic liquid;
soaking the membrane (<NUM>) with a soaking liquid;
subjecting the mixture in the membrane (<NUM>) to process conditions sufficient to cause pervaporation, wherein the process conditions comprise a temperature in a range of <NUM> to <NUM>;
recovering a permeate comprising a higher wt. % of water than the wt. % of water in the mixture and a retentate comprising a higher wt. % of organic liquid than the wt. % of the organic liquid in the mixture.