Nanoclusters

Abstract

The present invention relates to a system (300), method and generator (301) for producing solvated nanoclusters of a guest substance. The method comprises providing a container (302) containing a plurality of surfaces (304) distributed therein; introducing a solvent (103) within which the solvated nanoclusters are to be generated into the container such that the solvent comes in contact with the surfaces; and distributing a fluid guest substance within the solvent, wherein the plurality of surfaces comprises random packings or structured packings or both, wherein the packings are made of or coated with (i) permanent-magnetic material or (ii) dielectric material that has a quasi-permanent electric charge or dipole polarisation.

Claims

1. A method of producing solvated nanoclusters, the method comprising the following steps: providing a container with a plurality of surfaces distributed therein; introducing a solvent within which the solvated nanoclusters are to be generated into the container such that the solvent comes in contact with the plurality of surfaces; providing a guest substance in fluid form; and distributing the guest substance within the solvent, wherein the plurality of surfaces comprises random packings or structured packings or both, and wherein the packings are made of or coated with either (i) permanent-magnetic material or (ii) dielectric or charged/polarised material that has a quasi-permanent electric charge or dipole polarisation.

2. The method of claim 1, wherein the plurality of surfaces comprise packings made of or coated with permanent-magnetic material to provide a magnetic strength of from about 0.1 T to about 0.5 T, preferably wherein the permanent-magnetic material is ferritic stainless steel or neodymium.

3. The method of claim 1, wherein the plurality of surfaces comprise packings made of or coated with dielectric or charged/polarised material that has a quasi-permanent electric charge or dipole polarisation to provide a Coulombic field strength in the range of from about 10.sup.5 V/m to about 10.sup.7 V/m, preferably wherein the dielectric material is made from a resin, fluoropolymer, wax or other material which permanently retains memory of internal surface charge or polarisation.

4. The method of claim 1, wherein the packings are coated with solvophobic and/or solvophilic material to provide regions with solvophobic and/or solvophilic character, respectively.

5. The method of claim 1, wherein the plurality of surfaces comprises packings made of permanent-magnetic material and coated with dielectric or charged/polarised material that has a quasi-permanent electric charge or dipole polarisation.

6. The method of claim 1, wherein the plurality of packings comprises packings with a size in the order of from about 15 mm to about 150 mm.

7. The method of claim 1, wherein the method comprises providing and distributing more than one guest substance in fluid form.

8. The method of claim 1, wherein least one guest substance comprises a gas.

9. The method of claim 1, wherein at least one guest substance comprises a liquid, preferably an aqueous liquid, particularly preferably deionised water.

10. The method of claim 7, wherein the guest substances to be distributed within the solvent comprise a plurality of liquids.

11. The method of claim 1, wherein the plurality of surfaces comprises surfaces coated with an electrically insulating coating such as polyethylene, polypropylene, polyvinylchloride or polytetrafluoroethylene.

12. The method of claim 1, wherein the plurality of surfaces comprises structured packings arranged in a parallel configuration, preferably wherein the packings are in a mesh configuration, preferably wherein each mesh element comprises an aperture for receiving a portion of a means for delivery of the guest substance, particularly preferably wherein the means for delivery of the guest substance comprises an elongated tubular member for extending through the apertures of the mesh elements and optionally wherein the means for delivery of the guest substance comprises a plurality of outlet apertures for facilitating the distribution of the guest substance within the container.

13. The method of claim 1; wherein the method further comprises the step of cooling the contents of the container, preferably wherein a coolant is circulated within the container or surrounding the container, e.g., within an external jacket.

14. The method of claim 1, wherein the method further comprises agitating the contents of the container, preferably wherein the contents of the container are agitated by a fluid-liquid contact by an agitator, rocker or on inter-phase mass-transfer packings.

15. The method of claim 1, wherein the method further comprises the step of releasing the nanoclusters from the solvent by applying an acoustic-sonication or electromagnetic signal to the container or by adding a chemical agent such as a surfactant to the solvent containing the nanoclusters.

16. A generator for producing nanoclusters using the method of claim 1, the generator comprising: a container containing a plurality of surfaces distributed therein, a solvent inlet for introducing solvent which the solvated nanoclusters are to be generated into the container such that the solvent comes in contact with the surfaces; and a fluid guest medium inlet for introducing a guest substance in fluid form into the container for distribution within the solvent, wherein the plurality of surfaces comprises random packings or structured packings or both, wherein the packings are made of or coated with either (i) permanent-magnetic material or (ii) dielectric material that has a quasi-permanent electric charge or dipole polarisation.

17. The generator as claimed in claim 16 further comprising a fluid-solvent turbulence generator such as an agitator.

18. The generator as claimed in claim 16 further comprising an internal electric source located within the container such as a paddle-wheel, battery, dynamo, preferably further comprising a control circuit configured for controlling the generator.

19. A method for improving plant growth comprising watering a plant using water containing air and CO.sub.2 nanoclusters generated using the method of claim 1, wherein the solvent is water and the fluid guest medium comprises air and carbon dioxide.

20. A method for capture of CO.sub.2 and pollutants from flue-gases and air in solvents, the method comprising generating nanoclusters using the method of claim 1, wherein the plurality of surfaces comprise packings made of permanent magnetic material coated with dielectric material that has a quasi-permanent electric charge or dipole polarisation and further coated with a solvophobic coating.

21. A method for capture of gas and water in petroleum, diesel and oil-bio-based fuels, the method comprising generating nanoclusters using the method of claim 1, wherein the solvent is selected from among petroleum, diesel and oil-bio-based fuels and the plurality of surfaces comprise packings made of permanent magnetic material coated with dielectric material that has a quasi-permanent electric charge or dipole polarisation and further coated with solvophilic and hydrophilic coatings.

22. A system for generating solvated nanoscale features in a liquid, wherein the nanoscale features are gas, liquid or crystallite form and present in amounts beyond thermodynamic solubility, the system comprising a generator as claimed in claim 16 and one or more sensors, preferably wherein the sensors are selected from among a temperature sensor for sensing temperature associated with the contents of the container, a pressure sensor for sensing pressure associated with the generator and one or more pH sensors.

23. The system as claimed in claim 22 further comprising a data-acquisition system for recording the parameters monitored with said sensors at predetermined intervals.

24. The system as claimed in claim 22 further comprising a storage vessel for storing the generated nanoclusters.

25. The system as claimed in claim 22 further comprising a control circuit in communication with the generator and one or more of a gas source for supplying a gas medium, a liquid source for supplying a liquid medium, a vacuum pump and a cooling means for cooling the contents of the container such as an isothermal bath.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0150] Certain preferred embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[0151] FIG. 1 is a process diagram detailing a preferred system for use in performing the method according to the invention of producing solvated nanoclusters;

[0152] FIGS. 2a to 2e show portions of alternative preferred surfaces and the different spatial force distributions emanating therefrom;

[0153] FIG. 3 is a schematic view of a preferred arrangement of the plurality of surfaces within a preferred generator according to the invention;

[0154] FIG. 4a a perspective view of a preferred delivery mechanism for promoting guest-liquid mixing contact;

[0155] FIG. 4b is a plan view of a stacked assembly of meshes for use in combination with the delivery mechanism of FIG. 4a;

[0156] FIG. 4c is a perspective view of a preferred mesh of FIG. 4b;

[0157] FIG. 4d is a perspective view of the preferred stacked assembly of meshes of FIG. 4b and the delivery mechanism of FIG. 4a;

[0158] FIG. 5 is a graph generated following light scattering experiments and illustrates typical distribution of the Sauter mean diameter of nanoclusters produced by the method according to the invention at various magnetic intensities;

[0159] FIG. 6 is a graph illustrating the relationship between nanocluster Sauter mean diameter and time, and the enhancement to the nanocluster stability, at various magnetic strengths;

[0160] FIG. 7 is a graph illustrating the extent of structuring of water in the proximity of nanoclusters;

[0161] FIG. 8a is a graph illustrating the density of water containing nanoclusters of air over time at 25? C. and atmospheric pressure (STP), with upwards shift compared to pure, deionised water (0.99824 g/cm.sup.3) evident;

[0162] FIG. 8b is a graph illustrating the density of water containing nanoclusters of CO.sub.2 over time at 25? C. and atmospheric pressure (STP), with upwards shift compared to pure, deionised water (0.99824 g/cm.sup.3) evident; and

[0163] FIG. 9 is a process diagram detailing an alternative preferred system for use in performing the method according to the invention of producing solvated nanoclusters;

[0164] FIG. 10 is a schematic view of an alternative preferred generator according to the invention; and

[0165] FIG. 11 is a schematic view of another alternative preferred generator according to the invention.

DETAILED DESCRIPTION

[0166] It has surprisingly been found that chaotic, frustrated, irregular nanoclustersas opposed to spherical nanobubbles/nanodropletsmay be generated by enhancing the speed of molecular rearrangement of a fluid guest medium in a solvent using spatial force distributions which are intrinsic to surfaces in contact with the solvent and medium. That is, in the method according to the invention, nanoclusters are generated by direct action of internal spatial force distributions, i.e., internal fields, on the solvent and guest medium without the need for an external field to be applied, and the nature of the surface packings enhances this process cooperatively with the character of these internal force-field distributions. The spatial force distributions act on the atoms of the solvent and guest molecules to create local density undulations and oscillations in the solventtemporally and spatiallyin addition to those oscillations arising already from hydrodynamic interactions with packings. The surfaces thus facilitate the uptake of fluid-state guest species from the medium in nanoscale form, i.e., in supersaturated nanoclusters beyond conventional liquid-state guest dissolution.

[0167] Various embodiments of the present invention will be described in detail with reference to the drawings, where like reference numerals represent like parts and assemblies throughout the several views.

[0168] It will be appreciated that the invention should not be construed to be limited to the examples, which are now described; rather, the invention is construed to include any and all applications provided herein and all equivalent variations within the skill of the ordinary artisan.

[0169] Referring to the drawings, and especially to FIG. 1, a preferred system according to the invention for generating nanoclusters is shown, generally referred to herein by reference numeral 100. System 100 comprises generator 101 provided with a vessel 102 with a hollow interior region defining a volume of about 1000 cm.sup.3 which accommodates a plurality of surfaces (not shown in FIG. 1) tightly packed therein and liquid 103. Vessel 102 may be made of plastic. Liquid 103 may be deionised water, seawater, wastewater, brine water or another aqueous solution and is introduced into vessel 102 via an inlet (not shown).

[0170] Generator 101 further comprises a source 115 of a fluid guest medium in the form of a gas, liquid or supercritical fluid, to be supplied to vessel 102 for distribution within liquid 103. Source 115 may comprise single or multiple gas or liquid sources which may be selectively controlled for providing the guest fluid or combination of guest fluids to volume 102. An inlet conduit 118 facilitates the routing of the medium from source 115 into volume 102. A back-pressure valve 117 facilitates the controlled introduction of the medium from source 115 to volume 102 without the loss of liquid 103 from volume 102. A flow-meter 119 is provided for metering the flow of the medium to volume 102. In the event inlet conduit 118 is left open and source 115 is absent or disconnected, ambient air is the default fluid guest medium provided to generator 101, given that ambient-pressure operation to produce nanoclusters in the body of liquid 103 also takes place.

[0171] In the preferred embodiment shown in FIG. 1, a vacuum pump 111 is provided for evacuating volume 102 prior to introduction of liquid 103.

[0172] In use of system 100, the introduction of fluid medium from the single- or multicomponent-species fluid source 115 to volume 102 is controlled via a series of ball valves 120. Control of source 115 includes altering the series of ball valves 120 to route the gas or combination of gases to either vacuum pump 111 or a dump facility 121, should the need arise. A back-pressure cylinder 122 accommodates fluid flow if the back pressure valve 117 closes.

[0173] System 100 may be run in continuous-flow mode for both the liquid and medium, or in fed-batch mode for either.

[0174] Generator 101 further comprises a sealing means (not shown) for sealing volume 102. The sealing means may comprise a closure cap and a sealing gasket for operably engaging with the side walls of generator 101. The sealing gasket is preferably made of polytetrafluoroethylene; however, this is not to be considered limiting and other materials are contemplated for use as sealing gaskets within the scope of the invention.

[0175] In the preferred embodiment shown in FIG. 1, an isothermal bath 105 is provided for circulating a coolant through at least a portion of generator 101 through an inlet tube 107 of volume 102, though a cooling jacket or passageway (not shown) around volume 102 for cooling the contents within volume 102. The coolant is then returned to isothermal bath 105 via an outlet tube 108 of volume 102. The coolant may be a mixture of water and ethylene glycol. The coolant is preferably supplied at a temperature in the range of from about 263K to about 293K, and, in the case of solvate/hydrate nanocluster formation, more optimally in the range of from about 273K to about 283K.

[0176] A mechanical agitator (not shown) may be provided for agitating the contents of volume 102.

[0177] In the preferred embodiment shown in FIG. 1, a temperature sensor 113 is provided for sensing temperature associated with the contents of volume 102, a pressure sensor 114 is provided for sensing pressure associated with generator 101 and data-acquisition system 112 is provided for recording the temperature and pressure monitored with temperature sensor 113 and pressure sensor 114 at predetermined intervals. While FIG. 1 illustrates optional temperature and pressure sensors, it will be appreciated by those skilled in the art that additional or alternative sensors may be used to monitor other parameters which may be recorded by data acquisition system 112, for example pH sensors.

[0178] Generator 101 is controlled via a control circuit 116 in communication with source 115, vacuum pump 111, temperature sensor 113, pressure sensor 114, data-acquisition system 112, and isothermal bath 105.

[0179] FIGS. 2a to 2e each schematically show the interface of the body of liquid 103 in which the guest medium (not shown) is present at a portion of a preferred surface 104a, 104b, 104c, 104d and the different spatial force distributions emanating from that surface. Each of surfaces 104 may be organic or inorganic in nature and of variable geometry, e.g., ferritic Raschig rings 104b in the case of the preferred embodiment shown in FIG. 2b.

[0180] In each of FIGS. 2a to 2d, the z-axis represents the direction parallel to the interface with the body of the liquid 103 in which the guest medium (not shown) is present, in an effort to facilitate the formation of solvated nanoscale assemblies therein, and the x-axis is perpendicular to surface 104a, 104b, 104c, 104d, respectively.

[0181] FIG. 2a illustrates a portion of a surface 104a such as a structured or random packing, e.g., a Pall ring, which has been coated with a material which permanently retains memory of internal surface charge or polarisation, e.g., polytetrafluoroethylene or other wax-type material. This coating may be spray-deposited onto the underlying surface using electrostatic spray deposition (ESP). Alternatively, the coating may be made by exposing wax-type materials or molten polytetrafluoroethylene in a static electric field and then allowing solidification. There may be a plurality of such coatings of alternating surface charge or polarisation.

[0182] In FIG. 2a, networks of charges at surface 104a create spatial distributions of Columbic force which serve to promote the uptake of the guest species into liquid 103 in nanoscale form to differing extents (in the case of a multicomponent guest medium).

[0183] In a similar way, the presence of magnetism at surface 104b in FIG. 2b allows for a spatial distribution of magnetic force, which serves to induce restructuring in liquid 103 and refine intermolecular bonding so as to facilitate the solvent-molecule rotational and translational rearrangements necessary to facilitate formation of metastable solvated nanoclusters containing additional guest molecules. The magnetic character of surface 104b may be obtained using various ferritic stainless steels or carbon steel, or iron, cobalt, nickel, neodymium. The surface, e.g., packing such as Intalox saddles, may be made from this, or else a ferritic substance may be coated atop another underlying material such as ceramic or a non-ferritic metal, e.g., by magnetron sputtering or electrostatic spray deposition incorporating magnetic-material (e.g., iron) dust.

[0184] In the preferred embodiment shown in FIG. 2c, a dielectric coating or paint is applied to surface 104c to modulate the magnitude of the lines of Coulombic and magnetic force.

[0185] Suitable coating materials include ceramics or glass or polytetrafluoroethylene, typically polyethylene, polypropylene and polytetrafluoroethylene, all with a low dielectric constant, i.e., less than about 3-3.5 for the relative dielectric constant.

[0186] In the preferred embodiment shown in FIG. 2d, alternating patchwork arrangements of solvo-phobic and -philic regions 125 are placed and adsorbed atop surface 104d, e.g., peptides, and the surface physico-chemical architecture may be further optimised by those skilled in the art surface engineeringthereby advantageously maximising the extent of capture of the guest in the liquid 103 in nanoscale form from pure or multicomponent guest medium. The solvo-phobic and -philic regions may be tailored onto surfaces via a range of deposition methods, including, inter alia, plasma coating, chemical etching, solution-immersion processes and spray coating.

[0187] In the preferred embodiment shown in FIG. 2e, dipolar surface 104e features orientation and polarisation character with partly aligned dipoles 126. This polarisation effect facilitates further nanoscale capture of the medium by liquid 103, and those skilled in the art of polarisation materials and surface engineering may select optimal orientation-polarisation coatings for surfaces for targeted differential capture of particular species preferentially from a multicomponent guest medium. Polarised surfaces may be created by electro-spinning with a polymer melt.

[0188] Importantly, an advantageous aspect of the present disclosure is that none of the surfaces in FIGS. 2a to 2e are in direct electrical contact with the liquid-medium mixtures, thus preventing energetically inefficient electrolysis, should there be any underlying electrical conduction. The universal feature of the medium-drawing properties of the surface characteristics outlined in FIGS. 2a to 2e lies in the manipulation in the local density and intermolecular-bonding arrangements in the liquid/solvent molecules, which facilitates (differential-species) absorption therein in nanoscale form.

[0189] Thus, the present disclosure differs completely in concept from known fluid-to-nanoscale absorption methods. In addition, the Coulombic character of the thus-formed nanoclusters allows for facile adsorption of solvated agents and impurities thereon for use as delivery agents (e.g., medicines, plant/fish/tree nutrients, plant epigenetic agents and gene-edited chemicals in high-technology agriculture) to, for instance, improve crop yields in lower-light conditions. Reactive versions of guest species' atomistic moieties may also be made by virtue of nanophase formation, which generally serves to improve the liquid's anti-bacterial and chemical-reactivity properties.

[0190] FIG. 3 depicts a general embodiment 128 of a series of surfaces 135, 144 in terms of their arrangement in generator 101 and the body of liquid 103 within volume 102. This may be operated under either batch, fed-batch or continuous-flow modes. A series of rods 144 composed of the surface materials of choice are shown in FIG. 3 to be horizontally mounted. However, this is not to be considered limiting and the rods may additionally or alternatively be diagonally or vertically-mounted. One or more magnets 127, together with rods 144 provides for a good deal of contact area to effect maximal inter-phase mass transfer from the guest medium to the nano-dissolved state. The distribution of random or semi-ordered inter-phase transfer packings 135 assists in this guest mass transfer. The combination of magnetic materials in terms of suitably shaped rods 144, packings 135 and optionally other inter-phase mass-transfer geometries (not shown) may be provided with dielectric coatings to produce polarisation and charge/solvent-interaction distributions promoting guest-liquid (inter-phase) mixing. Suitable dielectric coatings include for example ceramics or glass or one or more polymers selected from among polyethylene, polypropylene and polytetrafluoroethylene, all with a low dielectric constant, i.e., less than about 3-3.5 for the relative dielectric constant, that is less than that of silica, which is ca. 4.

[0191] FIGS. 4a to 4d depict an alternative efficient arrangement of surfaces, wherein the series of surfaces comprises a plurality of permanent magnets 123 and a plurality of surface-polarised and charged materials 124 arranged in a parallel, radial configuration and connected to a plurality of mesh elements 129. Each mesh element 129 may itself be coated and in character advantageously in some of the manners described above, e.g., in connection with FIGS. 2a to 2e.

[0192] FIG. 4a shows delivery mechanism 131 or facilitating the distribution of the fluid medium and/or liquid medium to and/or within volume 102. Delivery mechanism 131 comprises an elongated tubular member 132 and a plurality of outlet apertures 134. As shown in FIG. 4c, each mesh element 129 comprises an aperture 130 for receiving a portion of delivery mechanism 131.

[0193] As may be seen from FIG. 4d, elongated tubular member 132 of delivery mechanism 131 is dimensioned such that it extends through apertures 130 of mesh elements 129. In the exemplary embodiment shown in FIGS. 4a and 4d, elongated tubular member 132 is operably mounted on a base member 133. Base member 133 may also comprise outlet apertures 134. Elongated tubular member 132 and base member 133 may each independently be made of any of suitable insulating materials, for example polymers such as polyethylene, polypropylene, polyvinylchloride and polytetrafluoroethylene. The surface-coating strategies mentioned in connection with FIGS. 2a to 2e may also be used to coat either or both elongated tubular member 132 and base member 133.

[0194] Outlet apertures 134 are dimensioned such that the guest medium is accommodated but liquid 103 is prevented from entering the interior volume defined by either elongated tubular member 132 or base member 133. Advantageously, the interior of tubular member 132 may be filled with a strong, i.e., from 0.2 T to 10 T, permanent magnet (not shown) to impart additional nanocluster-creation impetus.

[0195] In the preferred embodiment shown in FIG. 4a, packings 135 are placed within the volume near delivery mechanism 131, e.g., adjacent elongate tubular member 132, to enhance yet further liquid-medium inter-phase mass transfer of guest species into the nano-dissolved cluster state.

[0196] Apertures 134 on base member 133 are preferably positioned with respect to mesh elements 129 such that the medium introduced to volume 102 from source 115 is not trapped near the bottom of volume 102 by the material wire of mesh elements 129. FIG. 4b depicts the arrangement of apertures 134 with respect to the mesh elements 129. In the preferred embodiment shown in FIGS. 4a and 4b, apertures 134 extend radially on base member 133 away from the tubular member 132. This embodiment of the series of surfaces 131, 129, 123, 124, with packings 135, increases both the levels of liquid/guest medium exposure to the spatial force distributions and influence of the surfaces about 15-fold compared with embodiments without such a mesh arrangement and structured-in-volume arrangement of packings, and, as such, the inventor argues that this embodiment is furthermore scalable for industrial applications.

[0197] Once the solvent and guest medium are well-mixed inside generator 101, as outlined in the description of FIGS. 3 and 4, relative to strategies for inter-phase mass transfer, nanocluster formation continues apace.

Example 1Generation of Solvated Nanoclusters

[0198] Solvated nanoclusters were generated using a preferred method according to the invention as follows:

[0199] Prior to initiating the process, volume 102 was washed, cleaned and completely dried using a stream of air to avoid any contamination. Afterwards, volume 102 was examined for leakage by injecting nitrogen at a pressure of 1 MPa. The leakage test was to ensure the accuracy of pressure readings during nanocluster formation.

[0200] Various magnetic strengths were arranged as per FIGS. 4a and 4d inside volume 102, ranging from around 0.1 to 2 T for approximately uniform intensity distributions, in conjunction with ferritic Raschig rings coated with polytetrafluoroethylene.

[0201] 100 cm.sup.3 of deionised water 103 was loaded into volume 102 and the vessel inlet (not shown) subsequently sealed using a closure cap and a sealing gasket; this volume water 103 was found to afford good levels of reproducible performance.

[0202] Generator 101 was loaded with 100 bar gas from source 115 selected from oxygen, air, tetrahydrofuran and methane and the pressure was recorded during nanocluster formation, wherein the pressure associated with volume 102 was increased by injecting the selected gas from source 115 until the desired pressure was reached. In the exemplary experiment, up to about 3? bar of gas was loaded into volume 102.

[0203] The density distributions and refinement of solvent intermolecular interactions in volume 102 facilitates the generation of nanoclusters using the magnetic strengths and ferritic Raschig rings, with their associated projected spatial force distributions as shown in FIGS. 2a to 2e. To prevent electrolysis occurring within the volume 102, neither surfaces (magnets and ferritic Raschig rings), nor water 103 are in direct electrical contact.

[0204] Water 103 was saturated after about 2 hours of gas-water contact in the presence of mechanical agitation to render the water turbulent for better water-gas contact, leading to higher nanocluster-formation yields. It will be appreciated that the values described herein are provided by way of example only and that alternative values may be used.

[0205] The temperature of volume 102 was controlled by circulating a mixture of water and ethylene glycol as coolant in isothermal bath 105. The temperature of isothermal bath 105 was adjustable in the range of 275-298 K. A platinum resistance thermometer (Pt-100) 113 with an accuracy of 0.1 K was calibrated against a reference platinum resistance thermometer and used to measure the temperature of volume 102. The pressure associated with volume 102 was monitored by a transducer 114 with an uncertainty of +0.010 MPa.

[0206] Table 1 below shows the data for a range of pressures from atmospheric pressure up to about 3? bar gas obtained from data-acquisition program 112 which recorded temperature and pressure at different time intervals. This table illustrates that the levels of metastable guest accommodation in nanocluster form achievable from the method of Example 1 are significantly higher than those known heretofore.

TABLE-US-00001 TABLE 1 Stored CH.sub.4 and O.sub.2 levels in nanoscale hydrate crystallites or domains in water Guest accommodation Pressure Temperature w.r.t. Fluid (bar g) Form (? C.) Henry's Law Oxygen 3.1 Fluid Domain 20 2.36 Air 0 Fluid Domain 20 2.18 (O2); 1.52 (N2) THF 1.4 Hydrate 3.7 15.6 Crystallite Methane 3.2 Fluid Domain 20 25.8

[0207] Using pure water as an example, for methane, it is found that levels of gas solubility are 25 times higher than the Henry's-Law level for methane (as fluid nanodomains) and about 15-fold at lower temperatures in the form of hydrate nanocrystallite for THF. In the case of oxygen, levels for its gas solubility are over twice as great with the method of the present disclosure, using both pure O.sub.2 and air at high- and ambient-pressures.

[0208] Light-scattering experiments were performed to ascertain the size distribution of the solvated hydrated nanoclusters and a typical example is shown in FIG. 5 as a function of the magnetic strength, with a greater population of smaller nanoclusters formed under stronger magnetic action. This allows for the possibility of using magnetic intensity as a control agent for the regulating the formation of nanoclustersparticularly their relative size and population.

[0209] After the formation of hydrate nanoclusters, the water solution was stored under ambient condition (pressure, temperature) and the stability of the nanoclusters studied. The results show higher stability versus gradual agglomeration of the clusters under stronger magnetic-formation conditions, as illustrated in FIG. 6. In addition, the evolution of the OH blue shift in water molecules, indicating their more structured nature, was found to decline somewhat over time in the case of CO.sub.2 hydrate quasi-crystallite fluid-phase domains, as these domains and nanostructured water began to return slowly to the reference state of pure water, with slow, gradual release of the nanophase.

[0210] In a similar way, the density of the water was studied over time for both air and CO.sub.2 fluid-state nanoclusters, and FIGS. 8a and 8b show both exhibiting a density enhancement of water containing nanoclusters of air (FIG. 8a)/CO.sub.2 (FIG. 8b) relative to pure waterwhich shows the nanostructuring of the water. Again, there is a dissipation over time back towards the reference state with no nanoclusters, but this is very slowindicating the strong metastability of the nanophase over weeks to months.

[0211] The method of the present disclosure addresses species-selective capture from multicomponent guest fluids (either single- or multiple-phase) into nanoscale form. One possible realisation of this, although it should not be understood to be the limit of its scope, is a mixture of methane and carbon dioxide. The carbon dioxide Henry's-Law coefficient solubility in milligrams per litre is 30 times greater than methane's Henry's law coefficient solubility. The application of the method of Example 1 above to such a mixture leads to an 11-fold increase in carbon dioxide accommodation in water compared to the Henry's Law solubility level, and thus a significantly greater portion of carbon dioxide than methane is diffused into water, purifying the residual fluid-phase methane to a level in the range of from 97 to 97.5%. This has significant applications for example in the bio- and flue-gas industry for controlling methane production in agriculture and low energy carbon capture, respectively, or for treating bio-gas from anaerobic digestors (e.g., in the waste-water treatment industry).

[0212] A further exemplary realisation relates to airapproximated as a mixture between oxygen (20%) and nitrogen (80%), where the oxygen is enriched selectively in water in fluid nanodomain form with a composition therein of about two-thirds, at the relative expense of nitrogen, with a fluid nanodomain composition of around third. These results were obtained using sodium bisulphite to draw out the number of moles of true oxygen from the nanocluster state, beyond Henry's Law limit.

[0213] The species-selective uptake from a multicomponent fluid phase guest medium, i.e., the additional level of guest accommodation in the nanocluster state beyond regular thermodynamic solubility limits for guests, may be described by a modified form of a non-equilibrium form of Henry's Law y.sub.i*=K.sub.i*x.sub.i*, where * refers to nanoscale guest accommodation (in solvated nanocluster form, whether as a entropy- or kinetically-limited quasi solvate-crystallite or in a fluid-phase domain) for component i, K.sub.i* is the new, enhanced nano-dissolution parameter (in excess of Henry's Law), and y and x refer to fluid- and nano-phase mole fractions, respectively. Strictly, K.sub.i* is time-dependent, but, in practice, varies much more slowly compared to the residence times of many industrial processes, e.g., over weeks/months.

[0214] Plant growth is enhanced substantially using air nanoclusters in irrigation water formed in by the method described in Example 1 above, with the differential preferential uptake of oxygen into this nanoscale form (about two thirds), at the expense of nitrogen (about one third), with enhanced CO.sub.2 uptake too from air (enhanced to of the order of 1,500 ppm (air-equilibrium equivalent) from about 415 ppm in atmospheric air). Less nutrients and fertilisers are thus needed, as these adsorb efficiently to the nanoscale gaseous domains' surfaces, meaning that a substantial fraction (typically up to half, and sometimes a greater fraction) less fertiliser needs to be added. Results with potato, watercress, lettuce and basil found that up to 40% extra growth occurred in soil with half the customary level of fertiliser, with light-scattering cluster populations of the order of 10.sup.7 per ml. It was similar (?30-40% growth enhancement) with enhanced levels of CO.sub.2 nanocluster in water-spray aerosol fog. Reducing the light level by up to three-quarters had substantially less impact on nanocluster-enhanced growth approaches than by the same light-level reduction when simply using conventional water.

[0215] The recorded level of CO.sub.2 enhancement in the nanoclusters is important in the capture of this gas and other pollutants from both flue-gas and air. It was also observed that the method described in Example 1 above using a solvent fuel instead of water greatly enhanced the level of air and water in petroleum-based fuels as nanoclusters, and this can be applied readily towards other gases.

[0216] Referring to FIG. 9, there is illustrated another system 200 for generating nanoclusters, which is also in accordance with the present general teaching. System 200 is substantially similar to system 100 and like elements are indicated by similar reference numerals. The main difference between system 200 and system 100 is that system 200 includes a gas sparger 205 for enriching the fluid medium, i.e., for producing meso-scale droplets or bubbles prior to nanocluster formation, given that boosting the level of fluid mixing with the liquid is highly beneficial in increasing the efficiency of nanocluster generation.

[0217] A storage vessel 210 may be used for storing the nanoclusters. In system 200, storage vessel 210 is at 3-4? C. which slows very substantially nanocluster reverse cavitation and agglomeration to micro-size (and escape to gas phase). However, for longer-term storage (in terms of months), or for transport of the liquid containing nanoclusters, water containing nanoclusters may be (quench-) frozen straight after taking it out of volume 102. It is then thawed out for use later.

[0218] Notably, freezing the liquid containing nanoclusters at high pressure whilst it is still in volume 102 will allow for time-preservation of much higher levels of de-facto guest accommodation in nanoclusters. For example, it is possible to achieve elevated levels (thousands of mg/l) of O.sub.2 in ice, which may then be stored at ambient pressure in a freezer for periods of days and weeks; the gas will seep out of the ice, but slowly. The frozen nanoclusters may be stored in a cheap, commodity ?25 bar pressure-vessel bucket, e.g., made of plastic or aluminium, such as is commonly/routinely available in the process industries for intermediate pressurised storage during transport, and it could be kept in this vessel in a normal industrial/consumer freezer in a very economic manner for longer-term storage and transport with significantly elevated gas levels, and then used elsewhere when thawed, e.g., to gasify or aerate water bodies quickly.

[0219] By exposing the storage volume 210 to a ?10-100 kHz, 10-50 N acoustic-sonic impulse, the nanoclusters containing quasi-solvate-crystallites or hydrated/solvated nano-scale gas or liquid guest molecules/moieties are seen to essentially leave the liquid within hours, rather than the many weeks, or some months, of metastability that occurs otherwise. This is due to resonant sonication frequencies with capillary waves at the nano-domain/solvent interface increasing inter-phase leakage from the nano- to the traditionally-dissolved state. Similar guest-release phenomena were observed with selected surfactant agents.

[0220] An alternative preferred system according to the invention for generating nanoclusters and generally referred to herein by reference numeral 300 is shown in FIG. 11. System 300 comprises generator 301 provided with pipe-column 302. In the preferred embodiment shown in FIG. 11, pipe-column 302 is made of PVC and is approximately 1 m in length and 5.5 cm in inner diameter. Non-magnetic, austenitic stainless-steel (316L-grade) 16 mm Pall rings 304 are packed in column 302 at a density of 135 per litre.

[0221] Liquid 103 may be introduced into inlet 306 of pipe-column 302 via inlet conduit 341. A fluid guest medium may be supplied to pipe-column 302 from source 315 via a Mazzei Venturi air injector (0.75, 0584 model) 350 located upstream of inlet 306. A plurality of Neodynium-52 bar magnets 327 are placed radially around the conduit upstream of Venturi 350.

[0222] In use of system 300, the fluid guest medium and liquid 103 are exposed to Pall rings 304. The method may be performed by generating the nanoclusters in batch mode or under flow conditions, i.e., wherein liquid 103 and the medium distributed therein flow through pipe-column 302 and out of outlet 360 rather than being contained in pipe-column 302. In both embodiments, spatial force distributions in liquid 103 resulting from magnets 327 and Pall rings 304 facilitate the generation of solvated nanoclusters in excess of conventional guest-species solvation.

[0223] Liquid containing the nanoclusters may be removed from pipe-column 302 via outlet 360.

Example 2a

[0224] Hydrated air/propane nanoclusters were generated using a preferred method according to the invention as follows:

[0225] Prior to initiating the process, pipe-column 302 was washed, cleaned and completely dried using a stream of air to avoid any contamination. Afterwards, pipe-column 302 was examined for leakage by injecting nitrogen at a pressure of 1 MPa. The leakage test was to ensure the accuracy of pressure readings during nanocluster formation.

[0226] 430-grade stainless-steel 16 mm magnetic Pall rings 304 were packed in column 302 at a density of 135 per litre. The Pall rings had ferritic and magnetic susceptibility about 10% less than plain carbon steel.

[0227] For the generation of nanoclusters of air, water 103 from source 340 was introduced into and flowed through pipe-column 302 at a flowrate of 30-40 l/min, allowing full pull of Venturi 350 at around 3.5-5 l/min of ambient air, i.e., at standard temperature and pressure.

[0228] The temperature of the air-uptake experiments (into solvated air nanoclusters) varied from 8? ? C. to 14? C.

[0229] For the generation of nanoclusters of propane, propane cylinder 315 with a discharge regulator set at 5.5 bar g was added as a further guest medium source.

[0230] The temperature of propane-uptake experiment was 4? C., and circa 70 litres of this water containing solvated propane-rich nanoclusters was passed into a 100-litre tank, which was then sealed and pressurised initially at 5 bar g by propane cylinder, and then maintained at 4? C. under constant-volume (isochoric) conditions.

Example 2b

[0231] Hydrated air/propane nanoclusters were generated as for Example 2a but using 316- and 430-grade stainless-steel 16 mm magnetic Pall rings 304 wherein the Pall rings were spray-coated with polytetrafluoroethylene (PTFE) using electrostatic spray deposition to a thickness of circa 100 microns so as to have the internal spatial Coulombic distributions emanating therefrom into the mother liquor and guest mediumalongside magnetic spatial distributions of force.

[0232] Experiments were also conducted with non-magnetic coated and uncoated Pall rings, leading to a 2?2 factorial design of various packed-bed two-phase-flow configurations.

Results

[0233] In the case of atmospheric air uptake, with a view towards forming solvated oxygen-rich nanoclusters, it was desired to assess of the 2?2 cases of coated and uncoated Pall rings (magnetic and non-magnetic) as to what the level of nanocluster generation would be. The population of nanoclusters was seen to be largest in the case of the coated and magnetic Pall rings as per Example 2b abovesee Table 2 below for mass of oxygen in nanocluster form (beyond conventionally dissolved oxygen) from standard oxygen-titration analysis:

TABLE-US-00002 TABLE 2 Nanocluster population for different packing types Nanocluster oxygen mass Pall ring packing type (mg/l) Non-magnetic, uncoated 1.9 Non-magnetic, coated 5.7 Magnetic, uncoated 3.2 Magnetic, coated 9.4 ? 0.7

[0234] Using a statistical-effects model for the factorial design, it can be seen that both variables are statistically important, with the coating effect being particularly important, although the magnetic influence is importantwith an important magnetic-coating interaction as well.

Example 3

[0235] Having established the superiority of magnetic and coated Pall rings, system 300 was used for clathrate-hydrate nanocluster experiments. In terms of propane-hydrate nanoclusters, the use of reaction-titration analysis immediately after leaving the nanocluster generator quantified the level of propane dissolved as individual molecules (Henry's Law) and in nanoclustered form as a fluid (but not yet as a hydrate)about 95% and 3.5 times the Henry's-Law level at 5 bar g, respectively. Then, in the downstream tank after 3 hours of constant-volume conditions, the pressure had stabilised and propane-hydrate nanoclusters had formed. In this case, with the pressure having settled and additional propane absorbed from the gas-headspace phase, the conversion of fluid-phase propane nanoclusters into propane-hydrate nanoclusters (i.e., in crystallite form) took place, and the mass of propane in molecular (Henry), solvated fluid nanocluster and hydrate-crystallites was then about 97%, 1.35 times and 14.3 times Henry's-Law level at 5 bar g, respectively. The occupation of the crystallite hydrate nanoclusters was about 90% of the maximum theoretical level.

[0236] An alternative preferred system according to the invention for generating nanoclusters and generally referred to herein by reference numeral 400 is shown in FIG. 10. System 400 is substantially similar to system 300 and like elements are indicated by similar reference numerals. The main difference between system 400 and system 300 is that system 400 comprises vessel 402 packed with random packings 404a and structured packings in the form of vertically mounted rods 404b, meshes 404c and horizontally mounted rods 404d. All surfaces 404a, 404b, 404c and 404d possess one or more of magnetic, charged, dielectric, polarised, solvophobic, solvophilic and dipolar character such that in use of system 400 the surfaces emit one or more spatial force distributions with a strength in the pico Newton to nano Newton range (?5 pN to 10 nN) on atoms in the solvent and guest molecules to create local density undulations and oscillations in the solvent located in volume 402.

[0237] Surfaces 404b, 404c and 404d may each independently optionally be connected to an electric source. An extra fluid guest medium source 415 and conduit 418 may be provided alternatively, or in addition to, fluid guest medium source 315 and conduit 318.

[0238] Venturi 350 may be replaced aby an alternative mixer/enricher for micro-, meso-, macroscale droplets and bubbles, i.e., jet-screw, atomiser or the like.

[0239] Aspects of the present invention have been described by way of example only and it should be appreciated that additions and/or modifications may be made thereto without departing from the scope thereof as defined in the appended claims.