Materials for moisture removal and water harvesting from air

Patent metadata

Field	Value
Publication number	US-2017232383-A1
Application number	US-201515518724-A
Country	US
Kind code	A1
Filing date	Oct 14, 2015
Priority date	Oct 17, 2014
Publication date	Aug 17, 2017
Grant date	—

Abstract

A material for moisture removal and/or water harvesting from air may include a hydrophilic material containing micropores and a low water activity material confined within the micropores of the hydrophilic material. Apparatuses containing such materials and methods for moisture removal and/or water harvesting from air by using such materials are also described.

First claim

1 . A material for moisture removal and/or water harvesting from air, comprising:
a hydrophilic material containing micropores; and a low water activity material confined within the micropores of the hydrophilic material.

2 . The material of claim 1 , wherein the hydrophilic material is selected from the group of inorganic oxides, ceramic materials, inorganic polymers, organic polymers and plasma treated polymers.

3 . The material of claim 1 , wherein the hydrophilic material is selected from the group of silica, zirconium dioxide, zinc oxide, zeolites, titanium dioxide, doped titania, silver titanate, tungsten carbide, silicon carbide, titanium carbide and boron nitride.

4 . The material of claim 1 , wherein the hydrophilic material is a composite selected from the group of metal oxides/metal, metal oxides/ceramic, metal oxides/polymer, polymer/metal, polymer/ceramic, polymer/polymer.

5 . The material of claim 1 , wherein the hydrophilic material is in the shape of a powder, a pellet, a surface coating, a film, or nanotubes.

6 . The material of claim 1 , wherein the hydrophilic material exhibits self-cleaning properties.

7 . The material of claim 1 , wherein the hydrophilic material is a superhydrophilic material.

8 . The material of claim 1 , wherein the micropores of the hydrophilic material have a L/D aspect ratio greater than 2.

9 . The material of claim 1 , wherein the low water activity material is selected from the group of desiccants, hygroscopic materials and materials having water activity a w of less than 0.6.

10 . The material of claim 9 , wherein the low water activity material having the water activity a w of less than 0.6 is selected from the group of sodium chloride, sodium sulfate and lithium chloride.

11 . The material of claim 1 , wherein the low water activity material is confined within the micropores of the hydrophilic material by liquid deposition, vapor deposition, solid phase reaction, impregnation, ion-exchange, covalent bonding, electrostatic immobilization, sol-gel method, reactive deposition or incorporation.

12 . The material of claim 1 , wherein the material for moisture removal and/or water harvesting from air has a harvesting capacity of at least 5 kg/kg/h in air under saturated water vapor condition.

13 . An apparatus, comprising:
the material of claim 1 ; and at least a container or a drainage system for collecting water from the material.

14 . The apparatus of claim 13 , further comprising a mesh coated with the material for moisture removal and water harvesting.

15 . A method for moisture removal and/or water harvesting from air, comprising:
providing a material for moisture removal and/or water harvesting from air comprising:
a hydrophilic material containing micropores; and
a low water activity material confined within the micropores of the hydrophilic material; and
collecting water from the material.

16 . The method of claim 15 , wherein the material for moisture removal and/or water harvesting produces liquid water by promoting vapor condensation, droplet formation and water flow.

17 . The method of claim 16 , wherein the liquid water is wicked away by the hydrophilic material before the liquid water penetrates the micropores of the hydrophilic material.

18 . The method of claim 15 , wherein the moisture removal and/or water harvesting occur at a temperature above a dew point temperature.

19 . The method of any of claims 15 , wherein the hydrophilic material is selected from the group of inorganic oxides, ceramic materials, inorganic polymers, organic polymers, plasma treated polymers and composite materials.

20 . The material of any of claims 15 , wherein the low water activity material is selected from the group of desiccants, hygroscopic materials and materials having water activity a w of less than 0.6.

Assignees

• Univ Hong Kong Science & Tech

Inventors

• Yeung King Lun
• Ferdousi Shammi Akter

Classifications

• B01J20/3236

  containing metal, other than zeolites, e.g. oxides, hydroxides, sulphides or salts · CPC title

• B01J20/2808

  being less than 2 nm, i.e. micropores or nanopores · CPC title

• B01J20/28007

  with size in the range 1-100 nanometers, e.g. nanosized particles, nanofibers, nanotubes, nanowires or the like (carbon nanostructures B01J20/205) · CPC title

• B01J20/0281

  Sulfates of compounds other than those provided for in B01J20/045 · CPC title

• B01J20/28047

  Gels · CPC title