TWI641413B - Separation apparatus and separation method using graphene - Google Patents

Abstract

The separation apparatus and associated methods are provided in a cross-flow configuration wherein the pressurized source directs the medium along a path substantially parallel to at least one of the graphenes, from the inlet to the outlet. The medium flows through a plurality of perforated holes while the remainder of the medium and the unacceptable components of the medium flow out of the outlet.

Description

Separation device and separation method using graphene

The present invention relates to the deionization or desalting of porous graphene.

As freshwater resources become scarcer, many countries are looking for solutions that convert salt-contaminated water, most notably seawater, into clean drinking water.

The technology of demineralization of existing water is divided into four major areas, namely distillation, ion procedures, membrane procedures and crystallization. The most efficient and most utilized of these technologies are multi-stage flash distillation (MSF), multi-effect evaporation (MEE), and reverse osmosis (RO). Cost is the driving factor for all of these processes, where both energy and capital costs are significant. The RO and MSF/MEE two technologies are fully developed. Now, the best desalination solution requires 2 to 4 times the theoretical minimum energy limit established by simple water evaporation, which is in the range of 3 to 7 kJ/kg. Distillation and desalination methods include multi-stage flash evaporation, multi-effect distillation, vapor compression, solar humidification, and geothermal demineralization. These methods share a common measure that is a change in water state for desalination. These measures use heat transfer and / or vacuum Pressure to evaporate the brine solution. The water vapor is then condensed and collected to serve as fresh water.

The ion program desalination method focuses on chemical and electrical interactions with the plasma within the solution. Examples of ion program desalination methods include ion exchange, electrodialysis, and capacitive deionization. Ion exchange introduces a solid polymeric or inorganic ion exchanger into the brine solution. The ion exchanger binds to the desired ions in the solution so that they can be easily filtered out. Electrodialysis is the process of using cation and anion selective membranes and voltage potentials to create alternating channels of fresh water and saline solution. Capacitor deionization uses a voltage potential to pull a charged ion from a solution, capturing the plasma while allowing water molecules to pass.

The membrane desalination process uses filtration and pressure to remove ions from the solution. Reverse osmosis (RO) is a widely used desalination technique that applies pressure to a saline solution to overcome the osmotic pressure of the ionic solution. This pressure pushes water molecules through the porous membrane into the freshwater compartment while the ions are captured, producing a high concentration of saline solution. Pressure is a driving cost factor for these measures because pressure is required to overcome the osmotic pressure that captures the fresh water.

Crystalline desalination is based on the phenomenon that crystals are preferentially formed but do not include ions. Pure water can be isolated from dissolved ions by producing crystallized water (in the form of ice or methyl hydrate). In the case of simple freezing, the water is cooled below its freezing point, thereby producing ice. The ice is then dissolved to form pure water. The methyl hydrate crystallization is carried out using methane gas oozing through a brine solution to form methane hydrate, which occurs at a lower temperature than the water freezer. The methyl hydrate increases, promoting separation, It is then warmed for decomposition into methane and desalted water. The desalted water is collected and methane is recycled.

Evaporation and condensation for desalination is generally considered to be energy efficient, but requires a source of concentrated heat. When operated on a large scale, the evaporation and condensation used for desalination is usually in the same location as the power plant and is easily limited by geographical distribution and size.

Capacitor deionization is not widely used, probably because the capacitor electrode is easily contaminated by the removed salt and requires frequent maintenance. The necessary voltage tends to depend on the spacing and flow rate of the plates, and the voltage can be hazardous.

Reverse osmosis (RO) filters are widely used for the purification of water. The RO filter uses a porous or semi-permeable membrane, typically made of a cellulose acetate or polyimide film composite, typically having a thickness of more than 200 microns. These materials are hydrophilic. The film is often spirally wound into a tube-like form for ease of handling and film support. The film exhibits a pore size distribution of a random size wherein the pores of the largest size are small enough to allow passage of water molecules and do not allow or hinder the passage of ions, such as salts dissolved in the water. Although the general RO film has a thickness of 1 mm, the inherent random structure of the RO film defines a long and tortuous or tortuous path of water supply through the film, and these path lengths can be much larger than 1 mm. The long and random configuration of the paths requires large pressures to strip water molecules from the surface from the ions and then counteract the osmotic pressure to move the water molecules through the membrane. Therefore, the RO filter tends to be not energy efficient.

Figure 1 is an abstract illustration of the cross section of the RO film 10. In FIG. 1, membrane 10 defines an upstream surface 12 (which faces upstream ionized aqueous solution 16) and a downstream surface 14. The ions described on the upstream surface are selected to have a +-charged sodium (Na) and a -charged chlorine (C1). This sodium is illustrated as being associated with four solvated water molecules (H ₂ O). Each water molecule includes one oxygen atom and two hydrogen atoms (H). One of the water flow paths 20 in the RO membrane 10 of FIG. 1 is illustrated as extending from the aperture 20u on the upstream surface 12 to the aperture 20d on the downstream surface 14. Path 20 is illustrated as convoluted, but it is not possible to show the true meandering nature of the general path. Also, the path illustrated as 20 can be expected to be interconnected with a plurality of upstream apertures and a plurality of downstream apertures. The path 20 through the RO membrane 10 is not only convoluted, but rather may change over time as some of the holes are blocked by unavoidable debris.

Alternative water desalination, deionization or fluid separation is required.

In view of the foregoing, a first aspect of the invention is to provide deionization or desalting of a graphene having pores.

Another aspect of the present invention is to provide a method of separating a component from a medium comprising: providing a main sheet having at least one layer of graphene with a plurality of perforated holes selected to allow passage of the medium and not allowing the medium to be Passing the selected component; disposing the main sheet having at least one layer of graphene in the main chamber, the main chamber having a main inlet, a main outlet, and a main flow path below; and pressurizing the medium to make it substantially a path having at least one layer of graphene in parallel, from which the main inlet flows to the main outlet, the medium flows to The first surface of the main sheet having at least one layer of graphene, such that a portion of the medium flows through the plurality of perforated holes to the second side of the main sheet having at least one layer of graphene, while the remaining portion of the medium And the selected component that is not allowed to flow out from the main outlet.

Still another aspect of the present invention is to provide a separation apparatus comprising: at least one chamber having an inlet, an outlet, and a lower flow path; at least one sheet of graphene perforated to have a size suitable for allowing passage of the medium and not allowing a hole through which the selected component of the medium passes, the at least one piece of graphene being positioned in the at least one chamber; and a pressurized source of the medium coupled to the at least one chamber having the inlet, the pressurized source guiding the Passing a medium along a path substantially parallel to the at least one piece of graphene, from the inlet to the outlet, the medium flowing onto the first surface of the at least one piece of graphene, such that a portion of the medium passes through the plurality of A perforated hole flows to the second side of the at least one piece of graphene while the remaining portion of the medium and selected components of the medium that are not allowed to flow out of the outlet.

10‧‧‧RO film

12‧‧‧ upstream surface

14‧‧‧ downstream surface

16‧‧‧Upstream ionized water solution

20‧‧‧ Path

20d‧‧‧ hole

200‧‧‧Basic desalination, desalination or deionization equipment

201‧‧‧Unfiltered water

202‧‧‧Deionized water

210‧‧‧ channel

212‧‧‧Filter membrane (porous graphene sheets)

214‧‧‧Support room

216‧‧‧ slot

218‧‧‧ pump

220‧‧‧Support film

222‧‧‧ Path

224‧‧‧Collection container

226‧‧‧ upstream

227‧‧‧ upstream part

230‧‧‧ Path

232‧‧‧Drain valve

308‧‧‧Void hole

310‧‧‧graphene tablets

312‧‧‧ hole

520‧‧‧Firm

600‧‧‧Deionization or desalination equipment

612a, 612b‧‧‧porous graphene sheets

614‧‧‧Support room

620a, 620b‧‧‧

626a‧‧‧Upstream section or room

626b‧‧‧Down section or room

629‧‧‧ middle part or room

630a, 630b‧‧‧ empty contacts

632a, 632b‧‧‧ emptying valve

652‧‧‧ valve

652bs‧‧‧ hole

654a, 654b‧‧‧ cross flow valve

660‧‧‧ pump

700‧‧‧ Crossflow separation equipment

702‧‧‧Unfiltered media

704‧‧‧ Container

706‧‧‧High pressure pump

706a‧‧‧Secondary high pressure pump

708‧‧‧ valve

710‧‧‧cross flow chamber

Room 710a‧‧

710b-x‧‧‧Additional room

712‧‧‧ cross inlet

712a, 712b‧‧‧ housing

714‧‧‧ room exit

720‧‧‧Graphene film

721‧‧‧ hole

722‧‧‧The first or upper surface of graphene sheet 720

723‧‧‧Second or lower surface of graphene sheet 720

724‧‧‧Support film

726‧‧‧ hole

730‧‧‧Upstream flow path

732‧‧‧ below the flow path

733‧‧‧ catheter

734‧‧‧ valve

740‧‧‧ collection trough

740a‧‧‧ Container

742‧‧‧ Purified materials or media

1 is a conceptual cross-sectional view of a prior art reverse osmosis (RO) filter membrane; FIG. 2 is a conceptual diagram of a water filter using a perforated graphene sheet in accordance with one aspect of the present disclosure; FIG. 3 is applicable to FIG. A plan view of a perforated graphene sheet in the configuration showing the shape of one of the plurality of holes; FIG. 4 is a plan view of the apertured graphene sheet showing 0.6 nm Diameter perforations or pores and inter-perforation dimensions; Figure 5 is a plan view of a support sheet that can be used in conjunction with the apertured graphene of Figure 2; Figure 6 is a plurality of apertured graphene sheets used in accordance with aspects of the present disclosure A conceptual diagram of a deionization water filter for separating the concentrated ions; FIG. 7 is a simplified illustration of a vertical configuration generally corresponding to the configuration of FIG. 6, wherein the apertured graphene sheets are spirally wound and Enclosed in a cylinder; and Figure 8 is a conceptual diagram of a separation device in accordance with aspects of the present disclosure.

2 is a conceptual diagram of a basic desalination, desalination or deionization apparatus 200 in accordance with an exemplary embodiment or aspect of the present disclosure. In FIG. 2, channel 210 delivers ion-containing water to filter membrane 212 installed in support chamber 214. The ion-containing water can be, for example, sea water or brackish water. In an exemplary embodiment, the filter membrane 212 can be wound into a spiral in a known manner. The flow or pressure of the ion-containing water flowing through the passage 210 of Figure 2 can be provided by the gravity of the tank 216 or by the pump 218. Valves 236 and 238 allow for the selection of the source of the ion-containing water. In the apparatus or configuration 200, the filter membrane 212 is a perforated graphene sheet. Graphene is a single atomic layer thickness carbon atom layer that is bonded together to define a sheet 310, as illustrated in FIG. The thickness of the single graphene sheet is about 0.2 to 0.3 nanometers (nm). Multiple graphene sheets can be formed to have a greater thickness and correspondingly greater strength. As graphene sheets are enlarged or formed, multiple graphene sheets can be provided in multiple layers in. Alternatively, multiple graphene sheets can be achieved by laminating or positioning one sheet over another. For all of the specific examples disclosed herein, a single graphene sheet or a multiple graphene sheet can be used. Tests have revealed that multiple graphene layers maintain their integrity and act due to their own adhesion. This improves the strength of the sheet and in some cases improves flow performance. The carbon atom of the graphene sheet 310 of Fig. 3 defines a repeating pattern of a hexagonal ring structure (benzene ring) composed of six carbon atoms, which forms a honeycomb lattice of carbon atoms. The void holes 308 are formed by a ring structure of every six carbon atoms in the sheet and the voids are less than 1 nanometer wide. In fact, the skilled artisan will appreciate that the longest dimension of the void aperture 308 is believed to be about 0.23 nanometers wide. Thus, the size and configuration of the aperture 308 and the electronic nature of the graphene exclude the transport of any molecules through the thickness of the graphene unless there is a perforation. This size is too small to allow passage of either water or ions. To form the apertured graphene sheet 212 of Figure 2, one or more perforations as illustrated in Figure 3 are fabricated. A representative general or nominal circular aperture 312 is defined through the graphene sheet 310. Hole 312 has a nominal diameter of about 0.6 nanometers. The 0.6 nm size was chosen to block the smallest ions commonly expected in saline or brackish water, which are sodium ions. The general circular shape of the aperture 312 is affected by the fact that the edge of the aperture is partially defined by the hexagonal carbon ring structure of the graphene sheet 310.

The pores 312 can be made by selective oxidation, which refers to exposure to the oxidant for a selected period of time. It is believed that the aperture 312 can also be laser drilled. As described in the publication Nano Lett 2008, Vol. 8, no. 7, pg 1965-1970, the simplest perforation strategy is at high The graphene sheets were treated with diluted oxygen in warm argon. As described therein, vias or holes in the range of 20 to 180 nm were etched in graphene using 350 mTorr of oxygen in argon at 500 ° C for 1 atmosphere (atm) for 2 hours. The paper reasonably suggests that the number of holes is related to defects in the graphene sheets and that the size of the holes is related to the residence time. This is believed to be a preferred method of making the desired perforations in a graphene structure comprising a single or multiple sheets. The structure may be a graphene nanosheet and a graphene nanobelt. Therefore, the pores within the desired range can be formed by a shorter oxidation time. Another more relevant method as described in "Fabrication and Characterization of Large Area Semiconducting Nanoperforated Graphene Materials," Nano Letters 2010 Vol. 10, No. 4, March 1, 2010, pp 1125-1131 by Kim et al. A self-assembled polymer that produces a patterned mask suitable for use with reactive ion etching. The P(S-block MMA) block copolymer forms an array of PMMA columns that, upon re-development, form vias for the RIE. The pattern of the hole is extremely dense. The number and size of the holes are controlled by the molecular weight of the PMMA block and the weight fraction of the PMMA in the P(S-MMA). Either method may produce one or more apertured graphene sheets.

As stated, the graphene sheet 310 of Figure 3 has a thickness of only a single atom. Therefore, the piece is easy to be scratched. The deflection of the graphene sheet can be improved by applying a support structure to the sheet 212 or by providing more than one graphene sheet. In FIG. 2, the support structure of the apertured graphene sheet 212 (which may also be referred to as a support sheet) is illustrated as 220. The support structure 220 in this specific example is a perforated polytetrafluoroethylene sheet, sometimes known as polytetrafluoroethylene. alkyl. The structure 220 can also be a perforated polycarbonate film, a nanostructured carbon, other suitable polymeric materials, or sintered porous metal. The thickness of the support sheet may be, for example, 100 micrometers to 1 millimeter (mm).

It should be noted that in the apparatus or configuration of FIG. 2, the pressure of the ion-containing water applied to the apertured membrane 212 via pathway 210 may be provided by gravity from the trough 216, thereby emphasizing one aspect of the apparatus 200. . That is, unlike the RO film, the apertured graphene sheet 312 forming the apertured film 212 is hydrophobic, and the water passing through the perforation (312 of FIG. 3) is not affected by the wetting. The obstacle of gravity. Also, as described, the flow path length through the holes 312 in the graphene sheet 310 is equal to the thickness of the sheet, which is about 0.2 to 0.3 nm. This length is much smaller than the random path length extending through the RO membrane. Therefore, very little pressure is required to provide fluid flow, or conversely, the flow at the specific pressure in the apertured graphene sheet 310 is large. This can in turn be said to be a low energy requirement for ion separation. It is known to those skilled in the art that the pressure required to drive water against osmotic pressure in the RO membrane to pass the membrane includes a frictional component that causes heating of the membrane. Therefore, some of the pressure that must be applied to the RO membrane is not to overcome the osmotic pressure but to become hot. The results of the simulation show that the apertured graphene sheet significantly reduces the required pressure. In addition, the energy savings from reduced pretreatment and the reduced clogging over time due to the chemical and biological neutrality of graphene also result in significant savings. As described, in any particular example, the perforations 312 in the graphene sheet 212 (or graphene sheet 310 of FIG. 3) or the multiple graphene sheets of FIG. 2 are made to a suitable size to not allow in the source water. The smallest ion expected is passed. Therefore, the size is equal to or greater than the minimum The ions will not pass through the apertured graphene sheet 212 and it is expected that this ions will accumulate in the upstream face 226 of the graphene sheet support chamber 214. The accumulation of ions in the upstream "chamber" 226 is referred to herein as "sludge" and will eventually reduce the flow of water through the apertured graphene sheets 212, thereby making it less effective to deionize. As illustrated in Figure 2, an additional path 230 is provided along with a bleed valve 232 to allow the sludge to be emptied or discharged. Thus, the operation of the device or configuration 200 of Figure 2 can be a "batch" mode. The first mode of the batch operation occurs as the ion-containing water flows through the path 210, and the drain valve 232 closes to prevent flow. The ion-containing water fills the upstream face 226 of the support chamber 214. The water molecules are allowed to flow through the apertured graphene sheet 212 of FIG. 2 and through the support sheet 220 to the downstream face 227 of the support chamber 214. Thus, the deionized water accumulates in the downstream portion 227 for a period of time and can be used to draw out through the path 222 to the capture vessel, which is illustrated as tank 224. Finally, the accumulation or concentration of ions in the upstream portion 226 of the support chamber will tend to reduce the flow of water through the apertured graphene sheets 212. To empty the concentrated ion/water mixture accumulated in the upstream chamber or on the face 226, the valve 232 is opened allowing the concentrated ion/water mixture to be emptied while the upstream portion 226 is again filled from the tank 216 or Pump 218 contains ionized water. Valve 232 is then closed and another filtration cycle begins. This creates deionized water and the accumulation of deionized water in vessel 224.

4 is a diagram of a graphene sheet having a plurality of perforations, such as that of FIG. 3. The sheet of Figure 4 defines [three, four or five] holes. In principle, this flow rate will be proportional to the pore density. As the pore density increases, the flow through the pore is variable It is a "spoiler" that can adversely affect the flow at a particular pressure. Also, as the pore density increases, the strength of the underlying graphene sheet can be locally lowered. This reduction in strength can cause cracking of the film in some cases. The center-to-center spacing between the holes is believed to be close to the optimum for the 0.6 nm hole at a value of 15 nm.

Figure 5 is a simplified illustration of a sheet for support that can be used with the graphene sheet of Figure 2 or if multiple graphene sheets are used. In Fig. 5, the support sheet 220 is made of a filament 520 of polytetrafluoroethylene (also known as polytetrafluoroethane) which is arranged in a quadrilateral mesh and bonded or fused at the intersection thereof. The support sheet 220 may also be a perforated polycarbonate film, a nanostructured carbon, other suitable polymeric materials or sintered porous metal. As with the apertured graphene sheet, the dimensions in the sheet for support should be as large as possible to have maximum flow and match the sufficient strength. The spacing between adjacent filaments 520 oriented in the same direction may be nominally 100 nanometers and the filament may have a nominal diameter of 40 nanometers. The tensile strength of the graphene sheet is large, and thus a relatively large unsupported area in the supporting sheet should not cause a problem.

6 is a conceptual illustration of a deionization or desalination apparatus 600 in accordance with another embodiment or aspect of the present disclosure in which multiple different apertured graphene sheets are used. In FIG. 6, elements corresponding to those of FIG. 2 are indicated by similar reference letters and numbers. It will be appreciated that each "layer" in Figure 6 can be a single graphite sheet or a multiple graphene sheet. In the support chamber 614 of Figure 6, the upstream and downstream apertured graphene sheets 612a and 612b respectively divide the chamber into three volumes or portions, i.e., the upstream portion or chamber 626a, the downstream portion or chamber 626b, and the intermediate portion or Room 629. Each of the apertured graphene sheets 612a and 612b is combined with a support sheet. More specifically, the apertured graphene sheet 612a is supported by the sheet 620a, and the apertured graphene sheet 612b is supported by the sheet 620b. The perforations of the apertured graphene sheets 612a and 612b are different from each other. More specifically, the upstream graphene sheet 612a becomes porous due to the pores 612ac which do not allow chloride ions to flow or allow chloride ions to flow and allow water containing sodium ions to flow; the nominal diameter of these pores is 0.9 Meter. Therefore, chloride ions having an effective diameter greater than 0.9 nm cannot pass through the apertured graphene sheet 612a, but remain in the upstream portion or chamber 626a. Water containing sodium ions can flow through the apertured graphene sheet 612a into the intermediate chamber 629. The downstream apertured graphene sheet 612b is perforated with pores 652bs selected to not allow sodium ions to flow or to allow sodium ions to flow and to allow water molecules to flow; these pores are nominally 0.6 nanometers in diameter. Therefore, chloride ions having an effective diameter larger than 0.9 nm cannot pass through the pores 612ac of the apertured graphene sheet 612a, but water containing sodium ions can flow through the pores 612ac of the apertured graphene sheet 612a into the intermediate chamber 629. Sodium ions cannot pass through the downstream apertured graphene sheets 612b, so they remain or accumulate in the intermediate portion or chamber 629. Water molecules (H ₂ O) free of at least chlorine and sodium ions may flow from the intermediate portion or chamber 629 through the pores 652bs of the apertured graphene sheet 612b and into the downstream portion or chamber 626b, from which the deionized water may pass the path 222 and collection container 224 are collected.

As with the deionization configuration 200 of Figure 2, the apparatus or configuration 600 of Figure 6 accumulates or concentrates ions during a deionization operation. However, unlike the apparatus or configuration of Figure 2, the deionizer 600 produces at least partial separation. Ion concentration. More specifically, in the case of water containing chlorine and sodium ions, the upstream portion or chamber 626a of the apparatus 600 accumulates a sludge concentration consisting primarily of chloride ions and the intermediate portion or chamber 629 accumulates a major sodium ion concentration. These concentrated ions can be separately extracted by separate selection control of the emptying contacts 630a and 630b and their emptying valves 632a and 632b. More specifically, valve 632a can be opened to allow the concentrated chloride ions to flow from the upstream portion or chamber 626a to the collection vessel illustrated as tank 634a, and valve 632b can be opened to allow the concentrated sodium ions to be intermediate or Chamber 629 flows into a collection vessel illustrated as tank 634b. Ideally, the purge valve 632a is closed before the intermediate portion or groove 629 begins to empty, so that some pressure is maintained across the apertured graphene sheet 612a to provide water flow through the apertured graphene sheet 612a to aid in the sodium richness. The ionic sludge is flushed out of the intermediate chamber 629. The purge valves 632a and 632b are closed prior to deionization. The occluded and collected concentrated ions have economic value as for conversion to a solid state in the case of sodium or to a gaseous state in the case of chlorine. It should be noted that seawater contains significant amounts of barium salts and, if preferentially concentrated, has value as a catalyst for the pharmaceutical industry.

Cross flow valves 654a and 654b are also illustrated in FIG. 6, which are in communication with flow path 658 and upstream portion or chamber 626a and intermediate portion or chamber 626b, respectively. Unfiltered water 201 containing ions can be routed to flow path 658 by opening valve 652, or deionized water 202 can be provided by tank 224 by operating pump 660. From the pump 660, the deionized water flows through the check valve 656 to the path 658. The cross flow valves 654a and 654b are simultaneously opened and closed with the emptying valves 632a and 632b, respectively, to thereby assist the sludge by the The room is empty.

7 is a simplified diagram of a deionization or ion separation configuration in accordance with an aspect of the disclosure. Elements of Figure 7 corresponding to elements of Figure 6 are indicated by like reference numerals and numerals. In Figure 7, the apertured graphene sheets 612a and 612b are rolled or spirally wound into a cylindrical shape and are embedded in the housings illustrated as 712a and 712b, respectively, as is known from the RO technique. As in other specific examples, the graphene sheets 612a and 612b may be a single graphene sheet or a multiple graphene sheet. And, as in the previous specific examples, the multiple sheets improve their collective strength and flow efficiency.

Those skilled in the art will appreciate that ions other than chlorine and sodium can be separated from water by selective porous graphene sheets.

8 is a simplified diagram of a cross-flow separation device in accordance with an aspect of the disclosure. The separation apparatus, generally indicated by numeral 700, is assembled to deionize, desalt or separate selected components from other components, such as gases, particles, solutes, molecules and hydrocarbons or any other nanometer size. Or the constituents of the micron size are separated by the medium. In this particular example, unfiltered or pre-filtered media 702 is provided in a container 704 of suitable size. The medium can constitute a fluid or gas containing components to be separated from each other or a combination thereof. The unfiltered media 702 is delivered by gravity or otherwise delivered to a high pressure pump 706 that propels the media along a conduit or tube that may or may not have a valve 708. If the valve 708 is provided and in an open condition, the unfiltered medium enters the crossflow chamber, which is generally indicated by numeral 710. The chamber is provided with a cross flow inlet 712 at one end and a cross flow outlet 714 at the opposite end. Positioned in the chamber 710 At a position relatively lower than the inlet and the outlet is a graphene film 720.

As in the previous specific example, a single or multiple sheet graphene film 720 has a plurality of perforated holes 721 that are sized to allow passage of selected portions of the medium while not allowing the medium to otherwise Partially passed. Typically, the perforation diameter for gas separation ranges from 0.2 to 0.6 nm, the salt is used at 0.6 to 2 nm, and the hydrocarbon molecule is used at 10 to 100 nm. As in this previous embodiment, the film 720 is a layer of carbon atom layers bonded together to define a single atomic layer thickness of a sheet. The thickness of the single graphene sheet is about 0.2 to 0.3 nanometers (nm). The film has a first or upper surface 722 that is pressurized to flow through the medium and a second or lower surface 723 that is opposite the surface 722. All of the features and attributes of the graphene sheets described in the previous specific examples are provided in this specific example. However, in this embodiment, the pore size may range from an effective diameter of 0.6 nm to an effective diameter of 1.2 nm, as appropriate for filtering or separating the medium. In other words, some of the holes may have a diameter of 0.6 nanometers, some holes have a diameter of 0.9 nanometers, and others have a diameter of 1.2 nanometers. Any combination and ratio of holes of different sizes can be used. In the case of desalination or deionization of water, pores in this range are believed to be sufficient to not allow most of the sodium ions and chloride ions to pass through the graphene film while allowing water molecules to pass. In other embodiments, for the crossflow geometry device, the perforation diameter for gas separation ranges from 0.2 to 0.6 nm, for salt separation is 0.6 to 2 nm, and for hydrocarbon molecular separation is 10 to 100 nm. The selected range between 0.2 nm and 100 nm can be used in accordance with the configuration of the medium and the impermissible constituents. Furthermore, a specific range of from 0.2 nm to 100 nm can be used.

In some embodiments, a support sheet or structure such as a support film 724 may be disposed under the graphene film 722 to support the film. In other words, the support film 724 is positioned to abut the surface 723 of the film 720. The support film is perforated to have a hole 726 that is substantially larger than the hole 721. The support film 724 may be composed of polytetrafluoroethylene (which is sometimes referred to as polytetrafluoroethane). Other materials for the membrane 724 may be apertured polycarbonate membranes, nanostructured carbon, other suitable polymeric materials or sintered porous metals.

In the case where the graphene film 720 is embedded or positioned in the chamber 710, an upper flow path 730 is formed. The upper flow path allows the pressurized fluid to flow from the inlet 712 to the outlet 714 in a direction substantially parallel to the membrane. As a result, the medium flows tangentially throughout the film and the medium has a suitable size to pass through the different apertures 721 and portions of the support film 724 (if provided) into the lower flow path 732 below the graphene film. The constituents that do not flow through the aperture are routed through the outlet 714 along conduit 733 (which may be equipped with valve 734). From the valve, the unfiltered medium (components not allowed) is then directed to a particular end use. For example, if water is the medium, the collected sodium and chloride ions are collected for energy recovery purposes, such as in a voltaic battery or any other use. The purified media collected in the lower flow path is then directed to a collection vessel 740 that holds the purified material or medium 742.

It will be appreciated from the foregoing description that the pressurized flow of the medium in a direction substantially parallel to the film (or in other words tangentially oriented) allows the medium to flow through the hole while the unacceptable material being collected is forwarded Export moves. This "cleaning" of the film prevents agglomeration or other useless build-up of the unacceptable material on the film. This is believed to facilitate the flow of the allowed or purified material 742 to be collected in the container 740.

In some embodiments, the apparatus 700 can include any number of downstream crossflow chambers 710 in which letter suffixes are provided to each chamber and associated components. Thus, the impedient fluid material flowing through the outlet 714 of the chamber is directed to a secondary high pressure pump 706a that introduces the fluid into chamber 710a, which is constructed substantially the same as chamber 710. As a result, previously unacceptable ingredients and media are further purified for collection in container 740a, but the disallowed material is directed through the outlet to valve 734a, and the disallowed material is collected for some other end use. . For example, to remove selected ions, analytes or particles of a particular size, first chamber 710 and associated graphene sheets are first exposed to the medium, wherein the first graphene sheet has a second chamber 710a and associated Graphene sheets (which have smaller pore diameters and distributions) have larger diameter pores and distributions. If provided, the additional chamber 710b-x will be provided with a corresponding graphene sheet with a further reduced pore size. In other words, this staged crossflow chamber 710 can be configured such that it is less ion selective in the first chamber and more ion selective in the downstream chamber. As a result, much less work or extraction force is required at each additional stage to achieve the desired degree of filtration of the medium. This is advantageous because the device provides very improved filtration and much less energy required for each additional salt removal step.

The method of ionizing water (201) containing unwanted ions comprises the steps of perforating graphene sheets (310) to have a plurality of selected The water molecules are allowed to pass through and do not allow a hole (such as 312) through which selected unwanted ions (e.g., Na) pass, thereby producing apertured graphene (212). As an alternative, the thus perforated graphene sheets can be provided. The water (201) containing the unwanted ions is pressurized (216, 218) to thereby produce pressurized water. The pressurized water is applied to the first surface (212u) of the apertured graphene (212) such that water molecules preferentially flow to the second side (212d) of the apertured graphene sheet (212) than ions. The water molecule (202) is collected on the second side (212d) of the graphene sheet. In one mode of the method, the selected ion is chlorine, the nominal diameter of the pores of the chloride ion is not allowed to be 0.9 nm, and the nominal spacing of the holes is 15 nm. In another mode of the method, the selected ion is sodium and the nominal diameter of the pores that do not allow sodium ions is 0.6 nanometers and the nominal spacing of the pores is 15 nanometers. The method can include strengthening the apertured graphene sheet (212) with a support (220), which can be a polytetrafluoroethylene grid (520).

The method of ionizing water (201) containing unwanted ions comprises the steps of perforating a first graphene sheet (612a) to have a plurality of diameters selected to not allow selected first unwanted ions (eg, Chlorine) passes through and allows pores (312) containing water through which a selected second unwanted ion (e.g., sodium) is passed, thereby producing a perforated first graphene sheet (612a). The second graphene sheet (612b) is perforated to have a plurality of pores selected to allow passage of water molecules and not allowing the selected second unwanted ions to pass therethrough, thereby producing a perforated second graphene sheet (612b), wherein the holes have a first graphene sheet having the pores The diameter of the hole (612a) is small. First (612a) and second (612b) apertured graphene sheets are juxtaposed to thereby form a parallel sheet having a first side defined by the first apertured graphene sheet (612a), by the first The second side defined by the two-porous graphene sheet (612b) and the path (629) for liquid flow therebetween. The water containing the unwanted ions is applied to the first side of the parallel sheet (612a) such that water molecules preferentially flow through the parallel sheet (612a) and the path (629) to the second side of the parallel sheet than the ions To thereby produce nominal deionized water. The nominal deionized water molecules are collected from the second side (612b) of the side-by-side sheet.

The water deionizer comprises a graphene sheet (212) that is perforated to have pores (312) sized to allow water molecules to flow and not to allow first type ions (eg, sodium) to flow. A water source containing ions of this particular type is provided. A path (210, 226, 227) is provided for water containing ions of the particular type to flow through the perforated graphene sheet having pores (212). In a particular embodiment of the deionizer, a purge configuration (220, 232) is coupled to the path for flow for the flow to be diverted from the perforated graphene sheet having pores (212).

The separator (600) includes a first graphene sheet (612a) that is perforated to have pores sized to allow flow of water molecules and does not allow flow of the first type of ions and is perforated to have a size suitable for allowing water molecules to flow and not allowing The second graphene sheet (612b) in which the type II ions flow, wherein the second type ion (Na) is smaller than the first type ion (Cl). A source (210, 216, 218) containing water (201) of the first and second type ions is provided. Paths (210, 626a) are provided for the water containing the first and second types of ions (201) flowing to the first graphene sheet (612a), which is perforated to have pores sized to not allow the first type of ions to flow. As a result, (a) the first type of ions (Cl) accumulate in the upstream faces (626a) and (b) of the first graphene sheets (626a) which are perforated to have pores sized to not allow the first type of ions to flow. Water containing a second type of ion (Na) flows through the first graphene sheet (626a) that is perforated to have pores sized to disallow the flow of the first type of ions, to which the perforations are sized to not allow The downstream side (629) of the first graphene sheet (612a) of the first type of ion flowing pores. The separator (600) additionally includes a path (629) for flowing water containing the second type of ions to the graphene sheet (612b) that is perforated to have pores sized to not allow the first type of ions to flow. The upstream side of the ). As a result, (a) the second type of ions are accumulated on the upstream side (629) and (b) of the second graphene sheet (612b) which is perforated to have pores sized to not allow the second type of ions to flow. Water of the first and second type ions flows through the second graphene sheet (612b) that is perforated to have pores sized to disallow the flow of the second type of ions. The collection configuration (222, 224) is coupled to receive water (202) that does not contain the first and second type ions. Additional collection configurations (630a, 632a, 634a; 630b, 632b, 634b) can be provided to separately collect the accumulated ions.

A method of deionizing a fluid containing unwanted ions, comprising the steps of: providing at least one graphene sheet having a plurality of perforations selected to allow passage of fluid and not allowing at least one of the unwanted ions to pass therethrough a hole in which the at least one graphene sheet is formed; the cylindrical body is embedded in the casing, and the fluid containing the unnecessary ions is pressurized Thereby generating a pressurized fluid to flow through the housing; applying the pressurized fluid to the first surface of the apertured graphene of the cylindrical body such that the fluid preferentially flows to the at least one a second side of the apertured graphene sheet; and the fluid is collected from the second side of the at least one graphene sheet. An extension of the method is where the at least one ion is chlorine and the pores that do not allow the chloride ion to pass are nominally 0.9 nm and the nominal pore spacing is 15 nm. A further extension of the method is where at least one of the ions is sodium, and the pores through which the sodium ions are not allowed to pass are nominally 0.6 nm and the nominal pore spacing is 15 nm. The method can also provide a second set of at least one graphene sheet having a plurality of perforated holes selected to allow passage of fluid and not allowing another one or more of the unwanted ions to pass; the second set At least one graphene sheet is formed in the second cylindrical body; the cylindrical body is embedded in the second housing, and the fluid containing the unnecessary ions from the housing is pressurized to thereby generate a pressurized fluid Flowing through the second housing; applying the pressurized fluid to the first surface of the second set of at least one apertured graphene in the second cylindrical body such that the fluid preferentially precedes ions Flowing to a second surface of the at least one apertured graphene sheet of the second set in the second cylindrical body. An extension of the method is that the perforated pores of at least one graphene sheet in which unwanted chloride ions are not allowed to pass are nominally 0.9 nm, and the at least one of the second group that does not allow unwanted sodium ions to pass through The perforated holes of the graphene sheets were nominally 0.6 nm. The method can also provide the first housing having a lower ion exclusion selectivity than the second housing.

The fluid deionizer comprises a cylindrical body of at least one graphene sheet perforated to have a size suitable for allowing fluid flow and not allowing at least one special shape a pore of a type; a fluid source containing a particular form of ions; and a path for the fluid containing at least one particular form of ions to flow through the cylindrical body having the at least one graphene sheet perforated to have a pore. The deionizer may additionally comprise a second cylindrical body of at least one graphene sheet perforated to have pores sized to permit fluid flow and not permit another particular form of ion flow, wherein the second cylindrical body is in use In the path of the flow of the fluid. The cylindrical body of the at least one graphene sheet is wound or spirally wound. The deionizer additionally includes a purge valve associated with each cylindrical body and a path for the flow of the fluid to allow concentrated ion energy not allowed by the cylindrical body to flow to the collection vessel.

The fluid deionizer also includes at least one graphene sheet perforated to have pores sized to permit fluid flow and not permit at least one particular form of ions contained in the fluid; having at least one graphene sheet support a chamber having an upstream portion receiving the at least one graphene sheet; a fluid source containing the at least one particular form of ions; a path for flowing a fluid containing the at least one particular form of ions through the at least a graphene sheet perforated to have pores; and a purge valve associated with the upstream portion, the purge valve being placed in an open position to collect the at least one particular form of ions not permitted by the at least one graphene sheet. The fluid deionizer can comprise a porous medium supporting the perforated to have at least one graphene sheet of pores. The medium is selected from the group consisting of polytetrafluoroethylene, polytetrafluoroethane, polycarbonate, nanostructured carbon or sintered porous metal. The deionizer can provide a second at least one graphene sheet that is perforated to have a flow that is sized to permit fluid flow and that does not allow for the particular form of ions contained in the fluid, wherein the support The chamber has the second at least one graphene sheet such that an intermediate chamber is formed between the at least one graphene sheet and the second at least one graphene sheet, and a downstream chamber is formed under the second at least one graphene sheet, such that The downstream chamber collects fluid flow that does not contain ions of this particular form that cannot pass through the graphene sheets. The fluid deionizer can have a second purge valve, wherein the second purge valve is associated with the intermediate chamber and collects another particular form of ions that the second at least one graphene sheet does not allow when placed in an open position. The deionizer can additionally include a cross flow valve associated with the upstream portion, the purge valve and the cross flow valve simultaneously opening and closing to help empty the impermissible ion form from the support chamber.

A method of separating components from a medium, comprising the steps of: displacing a master sheet having at least one layer of graphene with a plurality of perforated holes selected to allow passage of the medium and not allowing passage of selected components of the medium; The main sheet having at least one layer of graphene is provided in the main chamber. The main chamber contains a main inlet, a main outlet, and a main flow path below. Extending the method by pressurizing the medium to flow from the main inlet to the main outlet in a path substantially parallel to the main sheet having at least one layer of graphene, wherein the medium flows to the at least a first surface of the primary sheet of graphene, such that a portion of the medium flows through the plurality of perforated holes to the second side of the main sheet having at least one layer of graphene, while the remaining portion of the medium and the medium The selected components that are not allowed to flow out are discharged from the main outlet. An extension of the method is to equip the plurality of perforated holes in the range of 0.6 to 1.2 nanometers for deionization of sodium and chlorine. The method can also be provided with the plurality of perforated holes of suitable size to selectively disallow passage of any selected components selected from the group consisting of ions, particles, analytes, gases, and hydrocarbons. The method is also in phase with the flow path A support film is provided on one side of the main sheet having at least one layer of graphene, and the film for support is selected from the group consisting of polytetrafluoroethylene, a perforated polycarbonate film, and a sintered porous metal. The method additionally couples the primary outlet to the secondary separation device and the secondary device to a second piece having at least one layer of graphene, the plurality of devices being selected to allow passage of the medium received by the outlet and not allowing a perforated hole through which the selected component of the medium passes; the second sheet having at least one layer of graphene is disposed in the second chamber, the second chamber having a corresponding flow path of the inlet, the outlet, and the lower portion; and the pressurized passage The secondary inlet and the medium received by the primary outlet are flowed from the secondary inlet to the secondary outlet in a path substantially parallel to the second sheet having at least one layer of graphene, the medium stream And onto the first surface of the second sheet having at least one layer of graphene, such that a portion of the medium flows through the plurality of perforated holes to the second side of the second sheet having at least one layer of graphene while the remaining portion The medium and selected components not permitted in the medium flow out of the secondary outlet.

A separation apparatus includes: at least one chamber having an inlet, an outlet, and a lower flow path; at least one sheet of graphene perforated to have pores sized to allow passage of the medium and not permit passage of selected components of the medium, the at least a piece of graphene positioned in the at least one chamber; and a pressurized source of the medium coupled to the at least one chamber having the inlet, the pressurized source directing the medium along a substantial portion and the at least one piece of graphite a parallel path from the inlet to the outlet, the medium flowing onto the first surface of the at least one piece of graphene, such that a portion of the medium flows through the plurality of perforated holes to the at least one piece of graphene Two sides, while the rest of the medium and The selected component that is not allowed in the medium flows out of the outlet. The apparatus may additionally comprise the plurality of perforated holes sized between 0.6 and 1.2 nanometers. The support film may be provided on the face of the at least one piece of graphene opposite to the flow path, wherein the support film is selected from the group consisting of polytetrafluoroethylene, perforated polycarbonate, and sintered porous metal. The apparatus can include an additional chamber coupled in series with the outlet of the at least one chamber, wherein the additional chamber is gradually displaced from the medium by utilizing at least one graphene sheet having a smaller pore diameter than the previous chamber Except for specific ingredients. The apparatus can also include an additional chamber coupled in series with the outlet of the at least one chamber, wherein the additional chamber utilizes at least one graphene sheet (which utilizes more selective ion exclusion) of the corresponding chamber An additional source of pressure coupled to the outlet of the at least one chamber allows for a gradual decrease in pressure.

Accordingly, the objects of the present invention can be seen to be satisfied by the structures presented above and methods of use thereof. Although only the best mode and the preferred embodiments have been presented and described in detail in accordance with the Patent Specification, it is to be understood that the invention is not limited thereto. Therefore, for the true scope and breadth of the present invention, the scope of the following claims should be cited.

Claims (18)

A separation apparatus comprising: at least one piece of graphene having a plurality of perforated holes having a desired size to allow passage of a fluid and not allowing passage of selected components of the fluid, the at least one piece of graphene having a first side and a second face opposite the first face; and a flow path substantially parallel to the at least one piece of graphene, the fluid being directed along the flow path, the fluid flowing to the first side of the at least one piece of graphene a first surface such that a portion of the fluid flows through the plurality of perforated holes to the second side of the at least one graphene sheet while preventing selected components of the fluid from flowing through the perforated holes . The apparatus of claim 1, wherein the plurality of perforated holes are sized to be in the range of 0.6 to 1.2 nm. The apparatus of claim 1, further comprising: a support film on a side of the at least one piece of graphene opposite to the flow path, the support film being selected from the group consisting of polytetrafluoroethylene and perforated poly The carbonate film and the sintered porous metal have a plurality of pores through perforation. For example, the apparatus of claim 1 wherein the nominal spacing of the holes is 15 nm. The apparatus of claim 1, wherein the at least one piece of graphene comprises a plurality of graphenes. The apparatus of claim 5, wherein the pores in one of the plurality of graphene sheets have different sizes than the pores in the other of the plurality of graphene sheets. The apparatus of claim 6, wherein the one piece of the plurality of graphenes is separated from the other of the plurality of pieces of graphene. The apparatus of claim 1 wherein the length of the flow path through the aperture of the sheet of at least one sheet of graphene is equal to the thickness of the sheet of the at least one sheet of graphene. The apparatus of claim 1, wherein the fluid stream is a pressurized stream of the fluid. A method of separating selected components from a fluid, comprising: directing the fluid to at least one sheet of graphene having a plurality of desired sizes to allow passage of fluid and not allowing passage of selected components of the fluid Perforated aperture, the at least one piece of graphene having a first side and a second side opposite the first side; and directing the fluid along a flow path substantially parallel to the at least one piece of graphene, the fluid flow Up to a first surface of the first side of the graphene, such that a portion of the fluid flows through the plurality of perforated holes to the second side of the at least one graphene sheet while preventing disallowing in the fluid The selected component flows through the perforated orifice. The method of claim 10, wherein the plurality of perforated holes are sized from 0.6 to 1.2 nm. The method of claim 10, wherein a support film is provided on one side of the at least one piece of graphene opposite to the flow path, the support film being selected from the group consisting of polytetrafluoroethylene, perforated polycarbonate film And the sintered porous metal, the support film having a plurality of holes by perforation. For example, the method of claim 10, wherein the holes The nominal spacing is 15 nm. The method of claim 10, wherein the at least one piece of graphene comprises a plurality of graphenes. The method of claim 14, wherein the pores in one of the plurality of graphene sheets have different sizes than the pores in the other of the plurality of graphene sheets. The method of claim 15, wherein one of the plurality of graphene sheets and the other of the plurality of graphene sheets are separated from each other. The method of claim 10, wherein the length of the flow path through the aperture of the sheet of at least one piece of graphene is equal to the thickness of the sheet of the at least one sheet of graphene. The method of claim 10, wherein the directing the fluid comprises directing a pressurized flow along a flow path.