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US-12623915-B2 - Colloidal flow-gate

US12623915B2US 12623915 B2US12623915 B2US 12623915B2US-12623915-B2

Abstract

The present invention provides a flow-gate design that utilizes chemo-responsive colloidal particles to control the flow rate therethrough. The flow-gate operates by changing the compactness of the colloidal particles, which changes in response to changes in pH or ionic strength in the flow medium or the surrounding environment. The design also allows the flow-gate as a size-discriminating filter. The ability to control the flow rate in response to changes in the flow medium or the environment makes the presently provided flow-gate useful for a variety of applications, including those that require automatic control of the flow rate, and automatic irrigation.

Inventors

  • Mais KHASKIA
  • Ofer Manor
  • Oz M. Gazit

Assignees

  • TECHNION RESEARCH & DEVELOPMENT FOUNDATION LIMITED

Dates

Publication Date
20260512
Application Date
20230215

Claims (15)

  1. 1 . A flow system comprising at least one flow-gate, wherein: said flow-gate comprises at least one flow-chamber, and a colloid of chemo-responsive colloidal particles contained in said flow-chamber; said chemo-responsive colloidal particles are characterized by having a Brucite-like structure, and by forming fluid-impermeable aggregates in response to a change in a concentration of at least one solute in said colloid; said chemo-responsive colloidal particles comprises ionic-responsive colloidal particles, and the system is configured to allow a flow of a fluid exhibiting at least an ionic strength at which aggregates of said ionic-responsive colloidal particles disassemble.
  2. 2 . The system of claim 1 , wherein said chemo-responsive colloidal particles comprises pH-responsive colloidal particles, and the system is configured to allow a flow of a fluid exhibiting at least a pH level at which aggregates of said pH-responsive colloidal particles disassemble.
  3. 3 . The system of claim 2 , wherein said chemo-responsive colloidal particles are characterized by having a general formula I: [ M ( 1 - x ) 2 + ⁢ M x 3 + ( OH ) 2 ] x + [ A n - ] x / n Formula ⁢ I wherein: M 2+ is a divalent metal ion, M 3+ is a trivalent metal ion, x is a molar ratio M 2 + ( M 2 + + M 3 + ) raging 0.2-0.33, A n− is an interlayer anion, and n is an integer ranging 1-3.
  4. 4 . The system of claim 3 , wherein M 2+ is selected from the group consisting of Mg 2+ , Cd 2+ , Co 2+ , Cr 2+ , Cu 2+ , Fe 2+ , Hg 2+ , Mn 2+ , Ni 2+ , Pb 2+ , and Zn 2+ .
  5. 5 . The system of claim 3 , wherein M 3+ is selected from the group consisting of Al 3+ , Cr 3+ , Dy 3+ , Er 3+ , Eu 3+ , Fe 3+ , Gd 3+ , Ho 3+ , La 3+ , Lu 3+ , Mn 3+ , Nd 3+ , Pr 3+ , Sc 3+ , Sm 3+ , Tb 3+ , Tm 3+ , Y 3+ , and Yb 3+ .
  6. 6 . The system of claim 3 , wherein A n− is selected from the group consisting of a halide ion, OH − , NO 3 − , NO 2 − , CO 3 2− , SO 4 2− , SO 3 2− and PO 4 3− .
  7. 7 . The system of claim 1 , wherein an average size of said chemo-responsive colloidal particles ranges 0.1-1000 μm.
  8. 8 . The system of claim 1 , wherein said chemo-responsive colloidal particles exhibit a broad particle size distribution, said broad particle size distribution is characterized by a particle size range that spans at least two orders of magnitude, and less than 30% of a total particle population in any particle size bin.
  9. 9 . The system of claim 1 , wherein said at least one flow-gate comprises at least one flow-permeable barrier positioned between said flow-chamber and said outlet.
  10. 10 . The system of claim 1 , wherein an amount of said chemo-responsive colloidal particles ranges at least 0.1-1 grams per 1 cm 2 of cross-sectional area of said flow-chamber.
  11. 11 . The system of claim 1 , wherein said flow-chamber further comprises a semi-permeable opening in communication with said colloid and with an aqueous medium in an environment outside the flow-gate, wherein said semi-permeable opening is impervious to said chemo-responsive colloidal particles and permeable to at least one solute in said aqueous medium.
  12. 12 . The system of claim 1 , wherein said solute is selected from the group consisting of hydronium ion (a hydrated proton), a monovalent cation, a divalent cation, a trivalent cation, a monovalent anion, a divalent anion, a trivalent anion, and any combination thereof.
  13. 13 . The system of claim 1 , wherein said chemo-responsive colloidal particles are pH-responsive colloidal particles.
  14. 14 . The system of claim 1 , wherein said chemo-responsive colloidal particles are ionic-responsive colloidal particles.
  15. 15 . A flow system comprising at least one flow-gate, wherein: said at least one flow-gate comprises at least one flow-chamber, and a colloid of chemo-responsive colloidal particles contained in said flow-chamber; said chemo-responsive colloidal particles are characterized by having a Brucite-like structure, and by forming fluid-impermeable aggregates in response to a change in a concentration of at least one solute in said colloid; said flow-chamber further comprises a semi-permeable opening in communication with said colloid and with an aqueous medium in an environment outside the flow-gate; said semi-permeable opening is impervious to said chemo-responsive colloidal particles and permeable to at least one solute in said aqueous medium; said chemo-responsive colloidal particles comprises ionic-responsive colloidal particles; the system is configured to allow a flow therethrough upon a change in an ionic strength level in said aqueous medium in said environment; and said ionic strength level in said aqueous medium is at least an ionic strength at which aggregates of said ionic-responsive colloidal particles disassemble.

Description

RELATED APPLICATIONS This application claims the benefit of priority of U.S. Provisional Patent Application No. 63/311,474 filed on Feb. 18, 2022, the contents of which are incorporated herein by reference in their entirety. FIELD AND BACKGROUND OF THE INVENTION The present invention, in some embodiments thereof, relates to hydrodynamics, and more particularly, but not exclusively, to colloidal particle-based flow-gates. Flow-gates for controlling fluid mass transport are common both in technology and nature. Technological applications usually make use of mechanical valves, which respond to human or controller signals. While such valves are common in macro-applications in domestic and industrial utilities, similar applications are found on microfluidic platforms. Applications in the micro- and nanoscale domain typically employ electrokinetic and magnetic gates for arresting flow. Colloidal particles are tiny particles, usually measuring between 1 and 1000 nanometers in diameter, that are suspended in a fluid. These particles can be naturally occurring (clay) or man-made, and are made of a wide variety of materials, including minerals, metals, polymers, glass and ceramics. Flow systems comprising colloidal particles utilize the properties of colloidal particles to control the flow of fluids. One way that colloidal particles can be used in flow systems is by using them to create stationary porous structures that can be used to control the flow of fluids and as filters. For example, a colloid of particles can be poured into a mold and allowed to solidify or be sintered. The resulting rigid structure will have a network of pores that are of the same size or close to the dimensions of the colloidal particles. The pore size can be adjusted by changing the size and/or size distribution and/or the amount of the colloidal particles, allowing for fine control over the flow rate of fluids through the structure, however, the structure is fixed once the colloidal particles are fused or otherwise solidified. However, the use of colloidal particles in flow gates can have some limitations, such as the potential for particle sedimentation, clogging or instability of the structure, which can affect the performance of the flow system over time. WO2016025873A1 provides a granular filtration media comprising a mixture of granular filtration media and less than 5% of nanofibers based on the dry weight, method of making the same and uses of the same for removing contaminants from water, including metals, heavy metals, synthetic or natural organic matters, colloidal or suspended particles to improve the chemical safety and purity of water for the purpose of water purification, specifically, one embodiment of the present invention disclosed is use of the granular filtration media to remove particulate lead from high pH water. Khalfa, K. et al. [“A calcined clay fixed bed adsorption studies for the removal of heavy metals from aqueous solutions”, Journal of Cleaner Production, 2021, 278, 123935] presented a study evaluating applicability of a calcined clay from southern Tunisia, in a fixed bed adsorption of metal pollutants, in treatment of metal loaded effluents. Giani de Vargas Brião et al. [“Reusable and efficient clay material for the fixed-bed neodymium recovery”, Sustainable Chemistry and Pharmacy, 2022, 25, 100623] reported the recuperate of neodymium from aqueous solutions through dynamic adsorption in a fixed-bed of expanded vermiculite (a natural clay mineral). Yang, C. et al. [“In situ nano-assembly of Mg/Al LDH embedded on phosphorylated cellulose microspheres for tetracycline hydrochloride removal”, Cellulose, 2020, 28, 301-316] reported an in-situ nano-assembly method that provided improved adsorption of soluble Mg/Al LDH load without compromising the porous structure of CMs, making Mg/Al LDH@PCMs suitable for water treatment. Prakash, R. et al. [“Bio-polymer modified layered double hydroxide extrudates: A novel approach towards adsorptive purification of water”, Journal of Water Process Engineering, 2020, 35, 101208] reported the preparation of modified LDH extrudates by one-pot co-precipitation and extrusion methods for column-based water and wastewater purification. SUMMARY OF THE INVENTION The present disclosure provides a technology that can be exploited, for example, to construct colloidal particles-based flow-gates. The flow-gates provided herein use the rapid response of colloidal particles to chemical changes in their environment, which is expressed in drastic changes in their through-flow capacity. This responsiveness is harnessed to control the flow of fluids through the flow-gate. For example, colloidal particles that are sensitive to changes in pH are used, according to some embodiments of the present invention, to create a flow gate that responds to changes in the acidity/alkalinity of the flow fluid and/or the immediate environment. Similarly, colloidal particles that are sensitive to changes in temperat