Use of surface modified porous membranes for fluid distillation

Patent metadata

Field	Value
Publication number	US-2017246592-A1
Application number	US-201515516123-A
Country	US
Kind code	A1
Filing date	Oct 5, 2015
Priority date	Oct 3, 2014
Publication date	Aug 31, 2017
Grant date	—

Abstract

In some embodiments, the present disclosure pertains to systems and methods for distilling a fluid by exposing the fluid to a porous membrane that includes a surface capable of generating heat. In some embodiments, the heat generated at the surface propagates the distilling of the fluid by converting the fluid to a vapor that flows through the porous membrane and condenses to a distillate. In some embodiments, the surface capable of generating heat is associated with a photo-thermal composition that generates the heat at the surface by converting light energy from a light source to thermal energy. In some embodiments, the photo-thermal composition includes, without limitation, noble metals, semiconducting materials, dielectric materials, carbon-based materials, composite materials, nanocomposite materials, nanoparticles, hydrophilic materials, polymers, fibers, meshes, fiber meshes, hydrogels, hydrogel meshes, nanomaterials, and combinations thereof. Further embodiments pertain to methods of making the porous membranes of the present disclosure.

First claim

What is claimed is:

1 . A method of distilling a fluid, said method comprising:
exposing the fluid to a porous membrane,
wherein the porous membrane comprises a surface capable of generating heat, and
wherein the heat generated at the surface propagates the distilling of the fluid.

2 . The method of claim 1 , wherein the fluid is selected from the group consisting of water, alcohols, organic solvents, volatile solvents, water-alcohol mixtures, and combinations thereof.

3 . The method of claim 1 , wherein the distilling occurs by a membrane distillation method.

4 . The method of claim 3 , wherein the membrane distillation method is selected from the group consisting of direct-contact membrane distillation, air-gap membrane distillation, sweeping-gas membrane distillation, vacuum membrane distillation, and combinations thereof.

5 . The method of claim 1 , wherein the distilling results in fluid desalination.

6 . The method of claim 1 , wherein the distilling results in fluid purification.

7 . The method of claim 1 , wherein the distilling results in solvent separation.

8 . The method of claim 1 , wherein the porous membrane is selected from the group consisting of polypropylene, polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polycarbonates, cellulose, and combinations thereof.

9 . The method of claim 1 , wherein the porous membrane comprises a microporous membrane.

10 . The method of claim 1 , wherein the porous membrane comprises pore sizes ranging from about 0.2 μm to about 5.0 μm in diameter.

11 . The method of claim 1 , wherein the surface spans an entire outer surface of the porous membrane.

12 . The method of claim 1 , wherein the temperature of the surface remains constant during distilling.

13 . The method of claim 1 , wherein the surface is capable of generating heat when exposed to a light source.

14 . The method of claim 1 , wherein the surface is associated with a photo-thermal composition, wherein the photo-thermal composition generates the heat at the surface.

15 . The method of claim 14 , wherein the photo-thermal composition generates the heat at the surface by converting light energy from a light source to thermal energy.

16 . The method of claim 14 , wherein the photo-thermal composition is selected from the group consisting of noble metals, semiconducting materials, dielectric materials, carbon-based materials, composite materials, nanocomposite materials, nanoparticles, hydrophilic materials, polymers, fibers, meshes, fiber meshes, hydrogels, hydrogel meshes, nanomaterials, and combinations thereof.

17 . The method of claim 14 , wherein the photo-thermal composition is hydrophilic.

18 . The method of claim 14 , wherein the photo-thermal composition comprises a polymer selected from the group consisting of hydrophillic polymers, polymer fibers, electrospun polymers, functionalized polymers, and combinations thereof.

19 . The method of claim 14 , wherein the photo-thermal composition comprises carbon-based materials selected from the group consisting of carbon black, graphite, graphene, graphene oxide, reduced graphene oxide, and combinations thereof.

20 . The method of claim 14 , wherein the photo-thermal composition comprises nanoparticles.

21 . The method of claim 20 , wherein the nanoparticles are selected from the group consisting of noble metal nanoparticles, metal oxide nanoparticles, semiconductor nanoparticles, gold nanoparticles, nanoshells, SiO 2 /Au nanoshells, nanorods, carbon black nanoparticles, graphene nanoparticles, graphene oxide nanoparticles, reduced graphene oxide nanoparticles, and combinations thereof.

22 . The method of claim 20 , wherein the nanoparticles are in the form an array on the surface.

23 . The method of claim 20 , wherein the nanoparticles are embedded in a hydrophilic material coated on the surface.

24 . The method of claim 23 , wherein the hydrophilic material is selected from the group consisting of polymers, meshes, fibers, mats, hydrogels, and combinations thereof.

25 . The method of claim 14 , wherein the photo-thermal composition is directly associated with the surface of the porous membrane.

26 . The method of claim 14 , wherein the photo-thermal composition is embedded in a polymer layer coated on the surface.

27 . The method of claim 26 , wherein the polymer layer is selected from the group consisting of polystyrenes, polyacrylonitriles, polymethyl methacrylates, polydopamine, and combinations thereof.

28 . The method of claim 14 , wherein the surface is associated with the photo-thermal composition through at least one of covalent bonds, non-covalent bonds, physisorption, hydrogen bonds, van der Waals interactions, London forces, dipole-dipole interactions, and combinations thereof.

29 . The method of claim 14 , wherein the photo-thermal composition is cross-linked to the surface.

30 . The method of claim 14 , wherein the surface is coated with the photo-thermal composition.

31 . The method of claim 30 , wherein the photo-thermal composition is cross-linked within the coating.

32 . The method of claim 1 , further comprising a step of exposing the surface to a light source, wherein the light source facilitates heat generation by the surface.

33 . The method of claim 32 , wherein the light source is selected from the group consisting of natural light, ultraviolet light, visible light, near infrared light, laser, incandescent light, fluorescent light, LED light, light derived from solar radiation, incident light, engineered light sources, and combinations thereof.

34 . The method of claim 32 , wherein light intensity from the light source is amplified by a light amplifier.

35 . The method of claim 32 , wherein the light amplifier comprises optical lenses.

36 . The method of claim 1 , wherein the heat generated at the surface propagates the distilling by converting the fluid to a vapor that flows through the porous membrane and condenses to a distillate.

37 . The method of claim 36 , wherein the heat generated at the surface propagates the distilling by creating a temperature gradient across the porous membrane, wherein the temperature gradient results in formation of a vapor pressure gradient that drives the formed vapor through the porous membrane.

38 . The method of claim 36 , further comprising a step of collecting the distillate.

39 . The method of claim 1 , wherein the method occurs by only heating the fluid near the surface of the porous membrane.

40 . The method of claim 1 , wherein the method occurs without the use of electric energy.

41 . A system for distilling a fluid,
wherein the system comprises a porous membrane, wherein the porous membrane comprises a surface capable of generating heat, and
wherein the heat generated at the surface propagates the distilling of the fluid.

42 . The system of claim 41 , wherein the fluid is selected from the group consisting of water, alcohols, organic solvents, volatile solvents, water-alcohol mixtures, and combinations thereof.

43 . The system of c

Assignees

• Univ Rice William M

Inventors

• Li Qilin
• Wu Jinjian
• Halas Nancy J
• Zodrow Katherine R
• Guo Haoli
• Xu Jiarui
• Yu Cong

Classifications

• B01D67/0088

  Physical treatment with compounds, e.g. swelling, coating or impregnation · CPC title

• B01D61/364 Primary

  Membrane distillation · CPC title

• B01D2313/36

  Energy sources · CPC title

• B01D71/0211

  Graphene or derivates thereof · CPC title

• B01D71/022

  Metals · CPC title