RU2800815C2 - Electrochemical flow reactor - Google Patents

Abstract

FIELD: electrochemical flow cells.

SUBSTANCE: invention relates to an electrochemical flow cell, including: a reaction chamber; first electrode; second electrode; and a separator placed between the first and second electrodes, wherein the separator, at least partially, forms a first channel within the reaction chamber, configured to receive a flow of the first fluid in contact with the first electrode, and a second channel within the reaction chamber, configured to receive flow of the second fluid in contact with the second electrode. Moreover, the separator includes a permeable membrane configured to provide electrical communication between the first and second electrodes through the fluid streams, at the same time limiting the exchange of fluid between the fluid streams, and the first electrode is an electrode with a static mixer function, including an electrically conductive section a static mixer forming a plurality of separating structures configured to separate the first fluid stream into a plurality of separate substreams at a plurality of locations along the length of the first electrode. The invention also relates to an electrochemical flow system, a method for electrochemical processing of a fluid flow, a method for electrochemical synthesis of a product.

EFFECT: effective performance.

28 cl, 17 dwg

Description

FIELD OF TECHNOLOGY TO WHICH THE INVENTION RELATES

The present invention relates to an electrochemical flow reactor such as a continuous flow electrochemical tubular reactor. This invention also relates to processes, systems and methods, including the use of an electrochemical flow reactor.

BACKGROUND OF THE INVENTION

Continuous flow reactors typically include a reaction chamber where fluid reactants are continuously fed to react chemically to form products that create a continuous effluent from the reaction chamber. The reaction chambers are typically immersed in a heating/cooling fluid, eg in a shell and tube heat exchanger configuration, to facilitate heat addition/removal from the reaction.

In continuous flow reactors, supported bed reaction chambers may be used in which the reaction chamber is filled with solid catalyst particles which provide surfaces with catalytic activity on which a chemical reaction can take place. Static mixers can be used to pre-mix the fluid streams prior to contact with, and downstream of, the carrier-bed reaction chambers to transfer heat between the central and outer regions of the reactor tubes. Static mixers include solid structures that interrupt fluid flow to promote mixing of the reactants prior to reaction in the carrier-bed reaction chambers and to assist in the formation of desired heat and mass transfer patterns downstream of these chambers.

Electrochemical flow reactors have been used in the treatment of fluid streams to remove dissolved metals by electrodeposition of dissolved metal ions to form solid metal products on the surface of electrodes placed in electrochemical flow reactors. Electrochemical flow reactors for water treatment have been designed for low flow, high surface area electrode systems for high throughput and control of dissolved metal removal from aqueous fluid streams having dilute/low concentrations of dissolved metal ions. Electrochemical flow reactors are also used in the electrosynthesis of various products, and in particular for the formation of reactants or intermediates.

There is a need for alternative or improved electrochemical flow reactors to provide efficient mixing, high mass transfer, and/or general applicability in industrial applications.

It will be understood that any prior art publications referenced herein do not imply an acknowledgment that any of these documents form part of the common knowledge in technology, in Australia or in any other country.

SUMMARY OF THE INVENTION

The present inventors have researched and developed alternative electrochemical flow reactors and have found that static mixers can be configured to act as an electrode within an electrochemical flow reactor to achieve efficient mixing, high mass transfer, and/or general applicability in industrial applications. Electrochemical flow reactors may include a static mixer electrode separated from the counter electrode by a permeable membrane. The static mixer electrode can be configured to enhance mass transfer and chaotic advection while providing high performance. The static mixer function electrode may be an electrode including a static mixer portion.

In one aspect, an electrochemical flow cell is provided, comprising:

reaction chamber;

first electrode;

second electrode; And

a separator placed between the first and second electrodes, wherein the separator at least partially defines a first channel within the reaction chamber designed to receive a first fluid flow in contact with the first electrode, and a second channel inside the reaction chamber designed to receive a second fluid flow media in contact with the second electrode,

wherein the separator includes a permeable membrane that creates ionic communication between the first and second electrodes through the fluid streams while limiting fluid exchange between the fluid streams, and

wherein the first electrode includes a static mixer portion forming a plurality of separating structures configured to separate the first fluid stream into a plurality of separate substreams at a plurality of locations along the length of the first electrode.

In one embodiment, the electrochemical flow cell is a continuous flow tubular reactor.

In one embodiment, the diameter of the static mixer portion of the first electrode may be approximately equal to the diameter of the first channel. The first electrode may be placed in contact with the separator. The separator and the second electrode can be placed concentrically and coaxially with the central longitudinal axis of the first electrode. The separator and the second electrode may be substantially cylindrical. The second electrode may constitute at least a portion of the wall of the reaction chamber.

In one embodiment, the first electrode including the static mixer portion may be designed to enhance mass transfer and chaotic advection by providing a plurality of separating structures configured to separate the fluid stream into a plurality of distinct substreams at a plurality of locations along the length of the first electrode.

In one embodiment, adjacent separating structures of the static mixer section may be placed at different angles of rotation around the central longitudinal axis of the static mixer section. The static mixer section may include a plurality of substantially similar building blocks arranged in series along the length of the static mixer section. The first electrode, including the static mixer section, can be configured to enhance chaotic advection by dividing the first fluid flow by more than 200 m ^-1 , corresponding to the number of cycles of first fluid flow separation within a given length along the static mixer section of the first electrode.

In yet another embodiment, the first electrode, including the static mixer section, is configured to operate at a Peclet number (Pe) of at least about 10,000. in Pa/m) from about 100 to 100,000. The first electrode, including the static mixer portion, may be configured to operate within the first channel to create a volumetric flow rate for the first fluid flow of at least about 0.1 ml/min.

In yet another aspect, an electrochemical flow system is provided, including at least a first electrochemical flow cell according to a first aspect, embodiment, or example of an electrochemical flow cell as described herein.

In one embodiment, the electrochemical flow system includes first and second electrochemical flow cells according to any aspect, embodiment, or example of an electrochemical flow cell as described herein. A plurality of flow conduits may be provided to connect the first electrochemical flow cell to the second electrochemical flow cell such that the first channel of the first electrochemical flow cell is in fluid communication with the second channel of the second electrochemical flow cell and the second channel of the first electrochemical flow cell is in communication. in fluid with the first channel of the second electrochemical flow cell.

In one embodiment, the electrochemical flow system further includes:

a pump for creating a fluid flow of the fluid streams;

a power source for regulating the current flowing through the electrodes, or the voltage applied to them;

a control device for regulating one or more system parameters including concentration, flow rate, temperature, pressure, and residence time.

In yet another aspect, a method for electrochemically treating a fluid stream is provided, comprising using an electrochemical flow cell according to any aspect, embodiment, or example of an electrochemical flow cell, reactor, or system thereof, as described herein. The method may be for treating waste water, removing dissolved metal ions from a fluid stream, or removing metal from a fluid stream.

In one embodiment of the method, an electrochemical flow cell including a first electrode containing a static mixer section may operate to provide at least one of:

chaotic advection by dividing the flow of the first fluid by more than 200 m ^-1 , corresponding to the number of cycles of dividing the flow of the first fluid within a given length along the section of the static mixer of the first electrode;

a Peclet number (Pe) of at least about 10,000;

pressure drop along the first electrode (in Pa/m) from about 100 to 100,000;

a volume flow rate for the first fluid stream of at least about 0.1 ml/min;

current density at the first and second electrode from about 1 μA·m ^-2 to about 1000 A·m ^-2 .

The method may include operating a first and a second electrochemical flow cell according to any aspect, embodiment, or example of an electrochemical flow cell as described herein, wherein a plurality of flow conduits connect the first electrochemical flow cell to the second electrochemical flow cell such that the first channel of the first electrochemical flow cell is in fluid communication with the second channel of the second electrochemical flow cell, and the second channel of the first electrochemical flow cell is in fluid communication with the first channel of the second electrochemical flow cell.

In yet another aspect, a method for electrochemically synthesizing a product is provided, using an electrochemical flow cell according to any aspect, embodiment, or example of an electrochemical flow cell, reactor, or system thereof as described herein.

In yet another aspect, a method is provided for removing substances from a fluid stream, using an electrochemical flow cell, reactor, or system thereof, according to any aspects, embodiments, or examples thereof, as described here. The substances may be metallic substances dissolved in the fluid stream.

It will be understood that other aspects, embodiments, and examples of an electrochemical flow cell, reactor, or system are described here.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention are described and illustrated below, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows a schematic representation of an electrochemical flow cell according to some embodiments;

Figure 2 shows a schematic representation of an electrochemical flow cell with a separator according to some embodiments;

Figure 3A shows a perspective view of an electrode with a static mixer function according to some embodiments;

Figure 3B shows (in a separate image) a perspective view of the static mixer portion of the static mixer electrode of Figure 3A;

Figure 3C shows (in a separate image) a sectional view of the static mixer portion of the static mixer function electrode of Figure 3A;

Figure 3D shows (in a separate image) a side view of the static mixer portion of the static mixer function electrode of Figure 3A;

Figure 4A shows a perspective view of an electrochemical flow cell according to some embodiments;

Figure 4B shows an exploded perspective view of the flow cell of Figure 4A;

Figure 4C shows a sectional view of the flow cell from Figure 4A;

Figure 5 shows a perspective view of the end cap of the flow cell of Figure 4A;

Figure 6 shows a schematic representation of an electrochemical flow system including two electrochemical flow cells, according to some embodiments;

Figure 7 shows chronoamperometric responses in 100 seconds at intervals of 50 seconds in steady state and 50 seconds at a constant flow rate from 10 to 400 ml min ^-1 at constant potentials of (a) -1.4 V, (b) -1, 6 V, (c) -1.8 V, and (d) -2 V (0.001 MK ₃ [Fe(CN) ₆ ]);

Figure 8 shows chronoamperometric responses in 100 seconds at intervals of 50 seconds in steady state and 50 seconds at a constant flow rate from 10 to 400 ml min ^-1 at constant potentials of (a) -1.4 V, (b) -1, 6 V, (c) -1.8 V, and (d) -2 V (0.01 MK ₃ [Fe(CN) ₆ ]);

Figure 9 shows chronoamperometric responses in 100 seconds at intervals of 50 seconds in steady state and 50 seconds at a constant flow rate from 10 to 400 ml min ^-1 at constant potentials of (a) -1.4 V, (b) -1, 6 V, (c) -1.8 V, and (d) -2 V (0.1 MK ₃ [Fe(CN) ₆ ]);

Figure 10 shows the performance of an electrochemical flow cell in removing copper ions from a 0.01 M sulfuric acid solution at three different concentrations of Cu ^{2 +} ;

Figure 11 shows (a) a visual image of an electrode acting as a static mixer before and after the processes, (b) an EDS analysis (Energy Dispersive X-ray Spectroscopy) and (c-e) an SEM image (from a scanning electron microscope) of an electrode with a function static mixer after 5 hours of electrolysis; And

Figure 12 shows copper concentration versus time during 24 hours of operation of an electrochemical flow cell in a split configuration embodiment.

DETAILED DESCRIPTION OF THE INVENTION

The present invention describes the following various non-limiting embodiments that are relevant in studies conducted to identify electrochemical flow reactors capable of providing efficient mixing, high mass transfer, and/or universal applicability in industrial applications. Surprisingly, it has been found that an electrode including a static mixer section could be configured within an electrochemical flow cell to achieve efficient mixing, high mass transfer, and/or general applicability in industrial applications. It has also been found that an efficient electrochemical reactor could be provided where the electrode including the static mixer portion was configured to enhance mass transfer and random advection. In addition, unexpected advantages in terms of system operation and productivity were revealed by the introduction of a separator between the electrode including the static mixer section and the counter electrode to accommodate each of the electrodes in the ion communication and in separate flow channels.

Terms

Throughout this description, unless specifically stated otherwise, or the context otherwise requires, reference to a single step, a composition in question, a group of steps, or a group of compositions in question, is to be construed as encompassing one or many (i.e., one or many) of these steps. , discussed compositions, groups of stages or groups of discussed compositions. Thus, as used here, the singular forms "a", "an", and "the" include plural aspects unless the context clearly states otherwise. For example, a reference to "a" includes a single object as well as two or more; a reference to "an" includes a single object, as well as two or more; the reference to "the" includes a single object, as well as two or more, and so on.

The term "and/or", for example, "X and/or Y" means either "X and Y" or "X or Y", and is considered to provide clear support for both values or any of the values.

As used here, the term "about", unless otherwise noted, usually means +/-10%, for example, +/-5% deviation from the specified value.

Throughout this description, the word "comprise" or variations such as "comprises" or "comprising" will be understood to mean the inclusion of a specified element, integer, or step, or group of elements, integers, or steps, but not the exclusion of any other element, integer or stage, or group of elements, integers or stages.

Those skilled in the art will appreciate that the invention herein is subject to variations and modifications in other ways than those specifically described. It should be understood that the invention includes all such variations and modifications. The invention also includes all of the steps, features, compositions and compounds listed or referred to in this description, individually or in the aggregate, and any and all combinations or any of two of these steps or features.

Each example of the present invention described herein is to be applicable, mutatis mutandis, to each and every other example, unless specifically stated otherwise. The present invention should not be limited in its scope to the specific examples described herein, which are for illustrative purposes only. Functionally equivalent products, compositions and methods are clearly within the scope of the invention as described here.

Unless otherwise stated, all technical and scientific terms used herein have the same meaning as is commonly understood by a person of ordinary skill in the field of technology to which the invention belongs. While methods and materials similar or equivalent to those described herein may be used to practice or test the present invention, suitable methods and materials are described below. In case of conflict, the present invention, including the definitions, will prevail. In addition, the materials, methods, and examples are illustrative only and are not intended to be limiting.

Electrochemical flow reactor

An electrochemical flow cell can be created, including: a reaction chamber, a first electrode including a static mixer section, a second electrode, and a separator placed between the first and second electrodes.

The separator may at least partially define a first channel within the reaction chamber to receive a first fluid flow in contact with the first electrode, and a second channel within the reaction chamber to receive a second fluid flow in contact with the second electrode. It will be appreciated that the separator allows ionic communication between the first and second electrodes via fluid flows. The separator may be a permeable membrane that limits the exchange of fluids between fluid streams. The static mixer section may form/include a plurality of separating structures configured to separate the fluid stream into a plurality of separate substreams at a plurality of locations along the length of the first electrode. It will be appreciated that the portion of the static mixer, as part of the electrode, is electrically conductive. Additional embodiments and details of the electrochemical flow cell are described as follows.

With reference to Figure 1, an electrochemical flow cell 100 (without a separator shown) includes a reaction chamber 102 containing a first electrode 104 and a second electrode 106. The second electrode 106 may form at least a portion of the wall of the reaction chamber 102 as shown in Figure 1. First electrode 104 may include a static mixer. The second electrode 106 may include a static mixer. The first and second electrodes 104, 106 may be placed concentrically, in a surrounding configuration, or in a parallel placement configuration.

Electrical power source 110 may be connected to first and second electrodes 104, 106 via respective first and second electrical conductors or cables 114, 116 to provide a potential difference or voltage to electrodes 104, 106. In some embodiments, first electrode 104 may act as the anode, and the second electrode 106 may act as the cathode. In some embodiments, first electrode 104 may act as the cathode and second electrode 106 may act as the anode. In some embodiments, a negative potential may be applied to the first electrode 104 and a positive potential may be applied to the second electrode 106. In some embodiments, a positive potential may be applied to the first electrode 104 and a negative potential may be applied to the second electrode 106.

The first and second electrodes 104, 106 may be formed from an electrically conductive material, or may include an electrically conductive surface coating. Additional characteristics of the electrodes 104, 106 are described below with respect to various embodiments and examples.

Pump 120 may be positioned to cause fluid to flow into reaction chamber 102 through first fluid flow conduit 124 through first inlet 134 in reaction chamber 102 to flow fluid through or around first electrode 104. The pump 120 may also be positioned to supply fluid to the reaction chamber through the second fluid flow conduit 126 through the second inlet 136 in the reaction chamber 102, for fluid to flow between the first electrode 104 and the second electrode 106. Fluid may then flow from reaction chamber 102 through a first outlet 144 adjacent to the first electrode 104 and a second outlet 146 closer to the second electrode 106.

In some embodiments, fluid may be supplied to the first and second flow conduits 124, 126 independently from the first pump 120 and the second pump 122, as shown in Figure 2. In some embodiments, the first and second flow conduits 124, 126 may be supplied to the reaction chamber 102 different fluids. The flow conduits 124, 126 may include pipes or tubes, for example.

With reference to Figure 2, an electrochemical flow cell 200 is shown in some embodiments (with separator shown). The flow cell 200 is similar to the flow cell 100 described in relation to Figure 1 and similar reference numbers are used for similar components. In addition to the components shown in the flow cell 100 and set forth above, the flow cell 200 includes a separator 202. The separator, in the embodiment as shown in Figure 2, at least partially separates the first fluid around or near the first electrode 104 , from the second fluid adjacent to the second electrode 106, between the first and second electrodes 104, 106. The separator 202 together with the walls of the reaction chamber 102 may form the first channel 204 and the second channel 206. The first electrode 104 may be placed in the first channel 204, and the second electrode 106 may be placed in or formed into the wall of the second channel 106. The inlets 134, 136 and the outlets 144, 146 may be configured such that the first fluid flows through the first channel 204 and the second fluid flows through the second channel 206. In some embodiments, the ratio between the side cross-sectional area of the first channel 204 and the second channel 206 may range, for example, from 0.01 to 100, from 0.1 to 10, from 0.5 to 5, from 0.3 to 1, from 0.5 to 0.9, from 0 .5 to 1.5, or 0.8 to 1.2.

Separator 202 may allow electrical charges to flow between electrodes 104, 106, but restrict all fluid from passing through separator 202. In some embodiments, separator 202 may create ionic communication between first and second electrodes 104, 106. For example, ions may pass from the first passage 204 into the fluid passage 206, while other fluid components may be prevented or substantially limited from passing through separator 202. In some embodiments, a small amount of fluid may pass through separator 202, although separator 202 may be configured to substantially prevent fluid from flowing through separator 202. In some embodiments, separator 202 may include a permeable membrane, a semi-permeable membrane, or a selectively permeable membrane. The characteristics of the separator 202 are described in more detail below according to various embodiments.

In some embodiments, the separator 202 and the walls of the reaction chamber 102 may be positioned to form channels 204, 206 in a parallel array configuration. Separator 202 may extend substantially planarly between channels 204, 206. In some embodiments, channels 204, 206 may extend substantially in parallel. In some embodiments, the second channel 206 may partially surround the first channel 204. In some embodiments, the first and second channels 204, 206 may be placed concentrically. In some embodiments, the first channel 204 may be completely formed by the inner surface of the separator 202. In some embodiments, the separator 202 and chamber 102 may be substantially cylindrical. In some embodiments, chamber 102 may be substantially coaxial with separator 202. In some embodiments, second electrode 106 may be substantially coaxial with first electrode 104. In some embodiments, all of chamber wall 102 and separator 202 may be substantially cylindrical and coaxial with a central longitudinal axis of the first electrode 104.

In some embodiments, cage 202 may form/include surface variations or undulations to increase the surface area of cage 202. In some embodiments, cage 202 may be corrugated. In some embodiments, the separator 202 may be substantially cylindrical with longitudinal folds. In some embodiments, separator 202 may be substantially cylindrical with circumferential folds.

The first electrode 104 (and/or the second electrode 106) may include a static mixer portion (e.g., a static mixing element, or SME) that forms a structure having a geometry that promotes mixing of the fluid flowing through the static mixer between the total volume of fluid and the electrode surface, as well as within the fluid itself. The first electrode may be a static mixer electrode. The static mixer electrode 104 may be designed to split the flow at a variety of different split locations along the length of the electrode 104 to promote thorough mixing by chaotic advection.

A static mixer may be composed of a plurality of separation structures placed at separation locations to separate the flow. Separation structures can be placed at different azimuth angles at different locations to separate the flow at different angles. In some embodiments, the splitter structures may be designed to split the stream into two separate substreams at each split point. In some embodiments, the separation structures may be designed to split the stream into at least three separate substreams at each separation point, such as three, four, five, six, seven, or eight separate jets, for example.

The static mixer geometry can be configured to enhance chaotic advection based on the properties of the particular fluid. The structure of a static mixer may include mesh elements including one or more intersecting blades or blades, braces, bumps, undulations and projections, spirals, corrugated plates, open configurations, closed configurations, pores, channels, cavities, tubes, and sandwich structures.

The geometry may repeat regularly along the length of the mixer, or may vary in size, type and/or shape. The geometry can also vary in its characteristic length from mixer scale down to nanometers, and technical features can be provided at all length scales in between.

With reference to Figures 3A-3D, an electrode 104 is shown with a static mixer function according to some embodiments. The electrode 104 includes a static mixer section 304 extending between the first end section 334 and the second end section 344. The end sections 334, 344 may be pipes or tubes for directing fluid through the static mixer.

The first end section 334 may constitute the first flow cell inlet 134, and the second end section 344 may form the first flow cell outlet 144, such as in the flow cells 100, 200 described above with respect to Figures 1 and 2. The end sections 334, 344 may also create an area of electrical contact to connect the electrode 104 to the power source 110.

The static mixer section 304 is shown in Figures 3B-3D without the end sections 334, 344 to more clearly show the geometry in some embodiments. The static mixer section 304 includes a plurality of rectilinear spacer structures arranged in repeating modules, with each subsequent module rotated 90° relative to the preceding module about the central longitudinal axis of the static mixer section extending from one end section to the other. The static mixer section 334 stimulates chaotic advection of the fluid flowing through the static mixer section 334 in a general direction along the central longitudinal axis, splitting and recombining the flow at multiple separation locations along the length of the static mixer section 334. The splitter structures divide the stream into a plurality of separate substreams at each split site, and the individual substreams are then combined before splitting again in the next splitter structure at the next split site.

Each time the flow splits and combines, it brings different portions of the fluid from the fluid volume into contact with the surface of the electrode 104, and multiple flow splits along the length of the static mixer increase the amount of fluid that comes into contact with the electrode 104.

In some embodiments, the diameter of the static mixer electrode 104 may be close to the inner diameter of the separator 202. That is, the first electrode 104 may be tightly inserted into the separator 202. volume formed by the separator 202. In some embodiments, the volume of the first electrode 104 may be in the range from 1% to 99% of the internal volume of the channel 204, optionally, from 10% to 90%, from 20% to 80%, from 30% to 70%, or 40% to 60%. In some embodiments, the volume of the first electrode 104 may be at least about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 98%, or 99% , the internal volume of the channel 204. Additional characteristics of the static mixer are described below according to various versions.

With reference to Figures 4A-4C, an electrochemical flow cell 400 according to some embodiments is shown in an assembled configuration (FIG. 4A), disassembled (FIG. 4B), and in cross section (FIG. 4C). Like components are identified by like reference numerals, and may include any of the features of the flow cells 100, 200 and components described with respect to Figures 1 and 2, or the static mixer electrode 104 described with respect to Figures 3A-3D.

The flow cell may include a first electrode 104, a second electrode 106, and a separator 202 placed between the first electrode 104 and the second electrode 106. The first electrode 104 may include an electrode 104 with a static mixer function, as described, for example, in relation to Figures 3A-3D.

Separator 202 may include a permeable, semi-permeable, or selectively permeable membrane that is substantially cylindrical and tightly encloses static mixer portion 304 of first electrode 104. Separator 202 and first electrode 104 may collectively form a first channel 204 along which fluid may flow, contact with the first electrode 104 and agitated by the static mixer section 304 (see Figure 4C).

Second electrode 106 may also be substantially cylindrical and form the outer wall of reaction chamber 102 surrounding separator 202 and first electrode 104. Separator 202 and second electrode 106 may collectively form a second channel 206 along which fluid may flow and contact second electrode 106. (see Figure 4C).

Separator 202 and second electrode 104 may be placed substantially concentrically and/or coaxially with the central longitudinal axis of first electrode 104.

Separator 202 and electrodes 104, 106 are held in place by two opposing end caps 500, shown in more detail in Figure 5, in some embodiments. Each end cap 500 includes a housing 501 defining a separator housing 502, a first electrode housing 504, and a second electrode housing 506.

The second electrode seat 506 is formed by a circular recess in the housing 501 to receive at least a portion of the end of the second electrode 106. The flow cell 400 may include a second electrode spacer 426 placed between the second electrode 106 and each end cap 500 to form a hermetic seal between the second electrode 106 and the second electrode receptacle 506 (see Figure 4B).

Cage seat 502 is formed by a circular recess (or, in some embodiments, by an annular recess) for respectively accommodating first end portion 232 or second end portion 242 of separator 202 (see Figure 4B). The body 501 defines an opening 516 located between the separator seat 502 and the second electrode seat 506, and a bypass from the opening 516 to form a second outlet 136 or a second inlet 146, respectively.

The first electrode seat 504 is formed by a cylindrical drilled hole or bypass channel designed to receive the respective end portions 334, 344 of the first electrode 104. socket 504 of the first electrode. The bypass can extend from the chamfer 514 to the opening 524 of the first electrode seat 504 on the other side of the housing 501 (see FIG. 4B). The first and second end portions 334, 344 of the first electrode 104 may extend through the bypass and opening 524, and respectively form the first inlet 134 or the first outlet 144.

A seal may be formed between the end portions 334, 344 and the end caps 500 from a sealing plate or gland cover 410 and a first electrode gasket 424 (see FIG. 4B). Gland cover 410 may include an electrode opening 414 for passing at least a portion of the end portions 334, 344, and a plurality of fastener holes (not shown) for receiving a plurality of fasteners 412. fasteners 412. Fasteners 412 may engage (eg, threaded) with fastener recesses 512 to press gland covers 410 against end caps 500, pinching first electrode spacers 424 between end caps 500 and gland caps 410 , and to the end portions 334, 344, thereby forming a seal between the first electrode 104 and the end caps 500.

The end caps 500 may be pulled together by a plurality of rods 440 extending between the end caps 500 and passing through a respective plurality of tie rod holes 542 formed in the housing 500 of each end cap 500. each end of each tie rod 440 to press the end caps 500 together and hold the separator 202 and the first and second electrodes 104, 106 between the end caps to form a reaction chamber 102 and a flow cell 400.

The electrochemical flow cells 100, 200, and 400 can provide enhanced electrochemical reaction capacities over conventional electrochemical flow cells due to the static mixer geometry of the first electrode 104 (and/or the second electrode 106) facilitating enhanced mixing of the fluid, such as for example chaotic advection to increase the volume of fluid brought into contact with the first electrode 104 and/or the second electrode 106.

Electrochemical flow cells 200 and 400 may provide the additional advantage that fluid streams can be held substantially separately in channels 204, 206 on either side of separator 202. while still allowing electrochemical reactions to take place. For example, in some processes, specific particles such as metal ions, for example, may be deposited on the surface of one of the electrodes 104, 106 by electrodeposition.

With reference to Figure 6, an electrochemical flow system 600 is shown in some embodiments. System 600 includes a first flow cell 200a and a second flow cell 200b arranged in series and powered by two power supplies 110a and 110b, respectively. Although in some embodiments both flow cells 200a, 200b may be powered by a single power source 110. Electrochemical flow cells 200a, 200b may be substantially similar to flow cells 200 or 400, and may include any of the features of the components described above with respect to Figures 2-5.

System 600 may include a first pump 120 that supplies a first fluid from a first source (Inlet 1) to a first inlet 134a of first flow cell 200a through a first flow conduit 124a of first flow cell 200a, and a second pump 122 that supplies a second fluid from a second source. (Inlet 2) into the second inlet 136a of the first flow cell 200a through the second flow conduit 126a of the first flow cell 200a. The first and second electrodes 104b, 106b of the second flow cell 200b may be supplied with an electrical voltage in reverse polarity relative to the voltage applied to the first and second electrodes 104a, 106a of the first flow cell 200a.

The system 600 may be configured such that the first fluid entering the first inlet 134a of the first flow cell 200a flows through the first channel 204a and exits through the first outlet 144a of the first flow cell 200a, then enters the second inlet 136b of the second flow cell 200b through the second flow conduit 126b of the second flow cell 200b, and flows out through the second outlet 146b into the first reservoir (Outlet 1). The system 600 can be further configured such that the second fluid entering the second inlet 136a of the first flow cell 200a flows through the second channel 206a and exits through the second outlet 146a of the first flow cell 200a; then enters the first inlet 134b of the second flow cell 200b through the first flow conduit 124b; through the first channel 204b of the second flow cell 200b and flows through the first outlet channel 144b into the second reservoir (Outlet 2).

For example, the source of the first fluid may include a contaminating metal such as copper, and it may be desirable to remove the contamination from the source of the first fluid and transfer the contamination to the second fluid. As it flows through the system 600, the contaminant will be deposited on the first electrode 104a of the first flow cell 200a from the first fluid, and if there is any contaminant left in the first fluid after passing through the first flow cell 200a, the contaminant will also be deposited on the second electrode 106b second flow cell 200b when the first fluid flows through the second channel 206b of the second flow cell 200b. The second fluid will pass through the second channel 206a of the first flow cell 200a and the first channel 204b of the second flow cell 200b to create electrical contact and complete the galvanic circuit for each flow cell 200a, 200b.

In conventional systems, when a contaminant has built up on an electrode due to electrodeposition, the electrode is removed from the system and the deposited contaminant is mechanically removed from the electrode surface. However, when the system 600 is used, it is not necessary to remove the electrodes.

Once fouling has accumulated as a result of deposition on the first electrode 104a of the first flow cell 200a and the second electrode 106b of the second flow cell 200b, the fluid sources can be switched by interchanging the flow conduits 124a, 126a or by using inline gate valves or valves (not shown) so that the first fluid flows through the second passage 206a of the first flow cell 200a and the first passage 204b of the second flow cell 200b, and the second fluid flows through the first passage 204a of the first flow cell 200a and the second passage 206b of the second flow cell 200b. In this way, contamination will be removed from the surfaces of the first electrode 104a of the first flow cell 200a and the second electrode 106b of the second flow cell 200b, and most of the contamination will be removed from the first fluid and deposited on the second electrode 106a of the first flow cell 200a and the first electrode 104b of the second flow cell 200b.

The electrochemical flow system 600 allows the electrochemical reaction to run indefinitely with relatively short interruptions to switch fluid paths, compared to conventional systems that require the physical removal and replacement of electrodes when material deposition on the electrodes has reached a certain threshold.

Electrochemical tubular reactor

An electrochemical flow reactor, such as the electrochemical flow cell described above, may be formed as a continuous flow electrochemical tubular reactor. The continuous flow electrochemical tubular reactor may be formed according to any of the embodiments or examples as described herein for the electrochemical flow cell.

It will be appreciated that the tubular reactor may be constructed in various shapes, lengths and configurations. For example, a tubular reactor may include a reactor chamber of circular or non-circular shape, or where the reaction chamber includes one or more flow channels that are circular or non-circular circumferential shape. Examples of non-circular shapes may include rectangular, isosceles triangle, elliptical, trapezoidal, and hexagonal shapes. In one embodiment, the tubular reactor or reactor chamber is substantially circular or cylindrical in shape.

The continuous flow electrochemical tubular reactor may include a reactor vessel defining a reactor chamber for receiving at least one static mixer electrode spaced at a predetermined distance from the at least one counter electrode. An electrode with a static mixer function may be formed by an electrode including a static mixer portion or a static mixing element as described herein. It will be appreciated that the static mixer portion or static mixing element, or at least a portion of any coating thereon, may be electrically conductive. The reactor also includes a permeable membrane that acts as a separator to fluidly separate the static mixer electrode from the counter electrode while still providing an electrical connection between the electrodes. The reactor may form a flow path for receiving a static mixer electrode that is separate from the flow path that contains the counter electrode. The pair of electrodes can create a pair of cathode and anode to initiate an electrochemical reaction in the tubular reactor. The static mixer electrode and counter electrode can be either cathode or anode, depending on the current flowing in the electrochemical cell. For example, the electrode pair can be reversed by switching the applied current. The static mixer electrode can also be configured to enhance mass transfer and random advection.

It will be appreciated that the tubular reactor is designed to allow at least a flow of the first fluid through the static mixer function electrode to be subjected to a random advection and electrochemical reaction treatment before exiting through the outlet port. It will also be appreciated that each flow passage in the tubular reactor may have at least one inlet and at least one outlet.

The reactor may include one or more chamber compartments in fluid communication with each other. The static mixer electrode can be configured as a replaceable electrode for insertion into a continuous flow electrochemical reactor, or configured as a permanent electrode. One or more reactors, or one or more reactor compartments, may be designed to operate in series or in parallel.

The length of the reaction chamber 102, separator 202, and electrodes 104, 106 can be in the range of 2 mm to 100 m, 10 mm to 10 m, 50 mm to 1 m, 100 mm to 500 mm, or 200 mm to 300 mm. The reactor vessel or chamber may have a diameter between 5 mm and 5 m, with counter and working electrodes sized to constitute an efficient electrochemical system. In some embodiments, the aspect ratio (L/d) of the reactor may be at least about 5, 10, 15, 20, 25, 30, 40, 50, 60, 75, or 100.

Separator

Separator 202 may include any porous material that allows ion transport but prevents fluid from flowing. The separator may include a permeable membrane, a semi-permeable membrane, or a selectively permeable membrane. In some embodiments, separator 202 may be formed from any one or more of the following materials: nonwoven fibrous material (cotton, nylon, polyesters, glass), polymeric films (polyethylene, polypropylene, polytetrafluoroethylene, polyvinyl chloride), ceramic materials, and materials of natural origin ( rubber, asbestos, wood). In some embodiments, the separator 202 may include polymeric materials with pores less than 20 Å. The separator 202 may be formed using dry and/or wet processing methods. The nonwoven separators 202 may include a fabricated sheet, web, or mat, with unidirectional or randomly oriented fibers.

In some embodiments, the separator 202 may include a liquid support membrane including solid and liquid phases contained within the microporous structure.

In some embodiments, separator 202 may include polymer electrolytes that form complexes with alkali metal salts that create ionic conductors that serve as solid electrolytes. Solid ionic conductors can serve both as a separator and as an electrolyte.

The separator 202 may be formed as a single layer or from multiple layers of material.

In some embodiments, separator 202 may be made from sintered powder material, such as ceramic materials, glasses, plastics, sintered materials, and combinations thereof, to form a membrane structure.

In some embodiments, separator 202 may be designed to allow ions to pass through while preventing fluid from entering. In some embodiments, separator 202 may be capable of passing a small amount of fluid through it.

The separator 202 may have an inner diameter configured to tightly enclose the first electrode 104. For example, the inner diameter of the separator 200 may be in the range of 0.5 mm to 5 m, 5 mm to 1 m, or 5 mm to 10 mm.

The thickness of the separator 202 may vary depending on its porosity. For nanoporous separators, the thickness can be between 1 micron and 100 microns (1-100 µm), and for microporous membranes, the thickness can be between 100 microns (µm) and 10 mm. The average pore size within the separator material can vary between 10 Å and 100 microns (µm).

It will be understood that the permeable membrane typically provides separate flow channels for each of the static mixer and counter electrodes, while maintaining the electrical connection required for the electrochemical flow cell. Typically, a permeable membrane prevents fluid from flowing through the membrane while allowing ion transport. For example, if during operation the static mixer electrode acts as the negative electrode (i.e., cathode) and the counter electrode acts as the positive electrode (i.e., anode), the fluid flow as the catholyte to flow through the static mixer electrode (i.e., i.e., cathode) can be prepared for a specific application that is different from fluid flow as an anolyte to flow through a positive counter electrode (i.e., anode). In other words, the permeable membrane creates ionic communication between the two electrodes for electrical connection while separating the two individual fluid streams flowing past each of the cathode and anode, which provides advantages in terms of performance and process flexibility.

The permeable membrane may be placed concentrically along the tubular reactor to separate the static mixer electrode from the counter electrode. The reactor may include a housing of an inner coaxial flow channel of one electrode and a housing of an outer concentric flow channel of the other electrode. The static mixer function electrode may be enclosed in an inner coaxial flow path, an outer concentric flow path, or both of an inner coaxial flow path and an outer concentric flow path. The flow channel may also be referred to here as a fluid flow channel.

The separator may be a semi-permeable membrane. The semi-permeable membrane can be a porous tubular film, a porous ceramic tube filter, or a porous plastic tube that tightly encloses the static mixer electrode. It will be appreciated that the semi-permeable membrane substantially limits the passage of fluid through the membrane while allowing transport of ions through the membrane to maintain electrical communication between the separated static mixer electrode and the counter electrode.

The separator may be a selectively permeable membrane. A selectively permeable membrane may provide selectivity as to which components may be allowed to pass through the membrane, such as specific fluids or ions. It will be understood that a selectively permeable membrane selectively restricts the passage of what cannot pass through the membrane, while allowing specific ions to pass through the membrane to maintain electrical communication between the separated static mixer electrode and the counter electrode.

It will be appreciated that each individual flow channel is provided with at least one inlet and at least one outlet. Separate fluid streams may be provided for an inner coaxial flow channel and an outer concentric flow channel. For example, the catholyte fluid stream may be designed to flow through the body of the inner coaxial flow path of the static mixer function electrode, and the anolyte fluid stream may be designed to flow through the body of the outer concentric flow path. As previously described, the static mixer electrode may also be aligned substantially along the axis of the tubular reactor.

Static mixer electrode

As discussed above, either the first electrode 104 or the second electrode 106, or both of the first and second electrodes 104, 106, may include a static mixer portion defining a geometry that promotes mixing of fluid flowing through or around the static mixer portion. This may be referred to as a static mixer electrode, or SME.

The reactor may include more than one static mixer electrode and/or more than one counter electrode. The counter electrode can also be equipped with an electrode with a static mixer function, for example, the cathode and anode in an electrochemical flow reactor can in each case be equipped with a separate electrode with a static mixer function. The static mixer function electrode may be concentrically enclosed within the inner coaxial flow passage, and the counter electrode may be enclosed within the outer concentric flow passage.

It will be appreciated that the static mixer function electrode may include an electrically conductive surface. An electrode with a static mixer function can act as an anode or as a cathode, depending on the direction of current flow. For an electrochemical flow cell, it will be understood in principle that the anode is the positive electrode where oxidation occurs and electrons are released from the reactant, and the cathode is the negative electrode where reduction occurs and electrons are consumed by yet another reactant.

An electrode with a static mixer function can be made from a material capable of providing current densities at any electrode in the range from 1 µA·m ^-2 to about 1000 A·m ^-2 . The static mixer electrode or its substrate may include an electrically conductive material, such as a conductive carbon material such as graphite, glassy carbon, or boron-doped diamond, metals, alloys, or intermetallic compounds, in the form of powders, sheets, rods, or bars, semimetals, or doped or narrow bandgap semiconductor materials, metal coated particles, conductive ceramic materials. Alternatively, the substrate may be made of a non-conductive material and then coated with an electrical conductor. The non-conductive materials can be particulate non-conductive materials such as plastics, ceramic materials, glasses or minerals, thermoset resins, thermoplastic resins, and natural products such as rubber and wood. The electrically conductive coatings may be formed from metals, metal alloys, intermetallic compounds, conductive compounds, or any electrically conductive materials as described above.

An electrode with a static mixer function can be obtained by subtractive processing using one method or combinations of processing methods, such as milling, cutting, turning, extruding, bending and twisting, casting, molding or forging, extrusion, pressing, using MEMS technology. systems (MEMS), additive manufacturing techniques, laser or electron beam welding, laser engineered meshing, material extrusion, sheet lamination, polymerization and photopolymerization, material or bonding material injection, and printing methods.

In some embodiments, the body or substrate of the static mixer electrode may be electrically conductive, such as metal or a metal alloy such as nickel, titanium, or stainless steel. In some embodiments, a conductive coating may be applied to the surface of the electrode, such as a titanium substrate coated with platinum. The coating may be formed from a metal, semi-metal, or narrow bandgap doped or semiconductor material, a conductive ceramic material or compound, a conductive form of carbon (e.g., graphite, graphene, or doped carbon materials), a conductive polymer (e.g., polyaniline), or their combinations. The coating may be applied to the surface by one or more of the following electrochemical methods, metal spraying, cold spraying, chemical or physical vapor deposition, dip plating, spray plating, spin plating, sintering, or other heat treatment methods, or any method. , which results in a thin layer of the proper material applied.

The static mixer electrode may be designed to promote agitation, including heat and mass transfer characteristics, to redistribute the fluid in directions transverse to the main flow, for example, in the radial and tangential or azimuth directions relative to the central longitudinal axis of the static mixer electrode. In particular, static mixer electrodes can be designed to enhance chaotic advection, thereby reducing the constraints on reaction rates that depend on diffusion. Static mixer electrodes can be designed to provide as much surface area as possible to interact with the flow to facilitate electrochemical reactions and improve flow mixing so that reactant molecules come into contact with the surfaces of the static mixer electrode more frequently. An electrode with a static mixer function can be given various geometries or aspect ratios to correlate with particular applications. The static mixer electrode may be configured to enhance the turbulence, mixing, and mass transfer characteristics of fluid streams. Configurations can also be designed to improve efficiency, degree of chemical or electrochemical reaction, or other properties such as pressure drop (while maintaining predetermined flow rates), residence time distributions, or heat and mass transfer coefficients.

An electrode with a static mixer function may include an electrically conductive composite substrate defining a plurality of passages designed to enhance mass transfer and random advection, for example, by separating fluid flows flowing between each of the passages. A substantial portion of the surface of the substrate may be electrically conductive.

An electrode with a static mixer function can be extended coaxially along the length and sideways across the diameter of the flow channel. In one example, the static mixer electrode sheath may be configured to extend coaxially along the length of the inner coaxial flow channel and laterally across the diameter of the inner coaxial flow channel to substantially occupy the entire inner coaxial flow channel.

The first electrode 104 may have an outer diameter to fit snugly within the separator 202. For example, the outer diameter of the first electrode 104 may be in the range of 0.5 mm to 5 m, 5 mm to 1 m, or 5 mm to 10 mm. In embodiments such as the flow cell 400 described with respect to Figures 4A-4C, where the first and second electrodes are placed concentrically and coaxially with each other, the inner diameter of the second electrode may be in the range of 0.5 mm to 5 m, from 5 mm to 1 m, or from 10 mm to 20 mm.

The ratio between the inner diameter of the separator 202 and the inner diameter of the second electrode 106 may be, for example, in the range of 0.02 to 0.99, 0.1 to 0.9, 0.3 to 0.7, or 0. 4 to 0.6.

An electrically conductive composite electrode substrate with a static mixer function may include an adjacent network of solid electrically conductive elements distributed throughout the internal coaxial flow path and designed to initiate chaotic advection of fluid flowing through the internal coaxial flow path. The adjacent network of solid electrically conductive elements may be formed as a lattice of interconnected segments configured to create a plurality of orifices to initiate chaotic advection of fluid flowing through the internal coaxial flow channel.

The static mixer function electrode may be configured in a configuration selected from one or more of the following general, non-limiting, exemplary configurations:

- open configurations with spirals;

- open configurations with blades;

- corrugated plates;

- multilayer structures;

- closed configurations with channels or openings;

- interconnected networks of braces, irregularities, undulations and ledges.

In one embodiment, a static mixer function electrode substrate may be configured into a grid having a plurality of integral blocks defining a plurality of flow paths designed to facilitate mixing of one or more reactants in fluids.

In yet another embodiment, the static mixer electrode may include a substrate provided with a grid of interlocking segments configured to provide a plurality of holes to promote mixing of the fluid flowing through the reactor chamber. The substrate may also be designed to promote heat and mass transfer, as well as to mix the fluid.

In some embodiments, the static mixer electrode may be designed to enhance chaotic advection, and, for example, turbulent mixing such as cross-sectional, transverse (with respect to flow) or localized turbulent mixing. The geometry of the static mixer electrode or its substrate can be configured to change localized flow directions or to split the flow more than a given number of times within a given length along the longitudinal axis of the static mixer electrode, such as greater than 100 m ^-1 , optionally greater than 200 m ^-1 , optionally more than 400 m ^-1 , optionally more than 800 m ^-1 , optionally more than 1500 m ^-1 , optionally more than 2000 m ^-1 , optionally more than 2500 m ^-1 , optionally more than 3000 m ^-1 , optionally more than 5000 m ^-1 . The geometry or configuration of the static mixer electrode or its substrate may include a predetermined number of flow separating structures within a given volume of the static mixer, such as greater than 100 m ^-3 , optionally greater than 1000 m ^-3 , optionally greater than 1×10 ⁴ m ^-3 , optionally more than 1×10 ⁶ m ^-3 , optionally more than 1×10 ⁹ m ^-3 , optionally more than 1×10 ¹⁰ m ^-3 .

The geometry or configuration of the static mixer electrode or its substrate can be designed to match the channel of a reactor cell, such as a tubular reactor. As previously described, it will be understood that the term "tubular" includes non-circular configurations, such as elliptical. The static mixer electrode or its substrate may be formed from or include a plurality of segments. Some or all of the segments may be straight segments. Some or all of the segments may include polygonal prisms, such as rectangular prisms, for example. The substrate may include a plurality of planar surfaces. The straight segments can be placed at several different angles with respect to the longitudinal axis of the substrate, such as two, three, four, five or six different angles, for example. The static mixer electrode or its substrate may include repeating patterns. The static mixer electrode or its substrate may include a plurality of similar structures periodically repeated along the longitudinal axis of the substrate. The geometry or configuration may be consistent along the length of the static mixer function electrode or its substrate. The geometry may vary along the length of the static mixer electrode or its substrate. The straight segments may be connected by one or more curved segments. An electrode with a static mixer function or its substrate, as a rule, can form a helical surface (helicoid). The static mixer electrode or its substrate may include a helical surface including a plurality of holes in the surface of the helicoid.

The dimensions of the static mixer electrode may vary depending on the application. The static mixer electrode or reactor including the static mixer electrode may be tubular. The static mixer electrode or reactor tube may have a diameter (in mm) in the range of, for example, 1 to 5000, 2 to 2500, 3 to 1000, 4 to 500, 5 to 150, or 10 to 100 The static mixer electrode or reactor tube may have a diameter (in mm) of at least about 1, 5, 10, 25, 50, 75, 100, 250, 500, or 1000, for example. the reactor tube may have a diameter (in mm) of, for example, less than about 5000, 2500, 1000, 750, 500, 250, 200, 150, 100, 75, or 50. The mixer or reactor chamber incorporating a static mixer function electrode can be set to a range suitable for industrial scale flow rates for a particular reaction. Aspect ratios may be in the range of, for example, about 1 to 1000, 5 to 750, 10 to 500, 25 to 250, 50 to 150, or 75 to 125. Aspect ratios may be, for example, less than than about 1000, 750, 500, 250, 200, 150, 125, 100, 75, 50, 25, 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, or 2. Aspect ratios may be, for example, more than about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100. Aspect ratios can be set to any two of "less than" and "greater" above.

Static mixer electrodes can be designed to enhance mixing and heat and mass transfer characteristics for laminar flow rates and turbulent flow rates. It will be appreciated that for Newtonian fluids flowing in a hollow tube, the correlation of laminar and turbulent flows with Reynolds numbers (Re) would typically correspond to laminar flow velocities where Re is >4000. It will be appreciated that static mixer electrodes reduce these typical Re values to create turbulent flow. Static mixer electrodes can be configured for laminar or turbulent flow velocities to provide enhanced characteristics selected from one or more of agitation, degree of reaction, heat and mass transfer, chaotic advection, and pressure drop. It will be understood that additional stimulation of a particular type of electrochemical reaction will require consideration of its own specific characteristics. For pipe flow, the Reynolds number can be defined as Re=ρuD _H /µ (ρ represents the density of the fluid in kg m ^-3 , u represents the average fluid velocity in m s ^-1 , D _H represents the hydraulic diameter of the pipe in meters , and µ represents the dynamic viscosity of the fluid in Pa·s).

In one embodiment, the static mixer electrode may be designed to operate at a Re value of at least 0.01, 0.1, 1, 5, 50, 100, 150, 200, 250, 300, 350, 400, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2500, 3000, 350 0, 4000, 4500, 5000 5500, 6000, 6500, 7000, 7500, 8000, 8500, 9000, 9500, 10000, 11000, 12000, 13000, 14000, or 15000. An electrode with a static mixer function can be designed to operate in the Re range from 0.1 to 20 00 , from 1 to 1000, from 10 to 800, or from 20 to 500. An electrode with a static mixer function can be designed to operate in the Re range from about 1000 to 15000, from 1500 to 10000, from 2000 to 8000, or from 2500 to 6000. An electrode with a static mixer function may be designed to operate at a Re value in the range between any two of the values described above as "at least".

In some embodiments, a static mixer electrode can be described by a Peclet number (Pe), which is another class of dimensionless quantities important for continuum transport phenomena. The Peclet number represents the ratio of the rate of advection of a physical quantity in a flow to the rate of diffusion of the same quantity under the influence of an appropriate gradient. In the context of particle or mass transport, the Peclet number is the product of the Reynolds number (Re) and the Schmidt number (Sc). In the context of thermal fluids, the thermal Peclet number is equivalent to the product of the Reynolds number (Re) and the Prandtl number (Pr). The Peclet number is defined as: Pe=advective transport velocity/diffusion transport velocity. For mass transfer, it is defined as: Pe _L =Lu/D=Re _L Sc. For heat transfer, it is defined as PeL=Lu/α=Re _L Pr, where α=k/ρc _p . L represents the characteristic length, u represents the local flow velocity, D represents the mass diffusion coefficient, and α represents the thermal conductivity, ρ represents the density, and c _p represents the heat capacity. A static mixer electrode can be designed to provide higher Peclet values to enhance chaotic advection to dominate diffusion to create a more even distribution of residence times and reduce dispersion. In other words, static mixer electrode configuration to achieve higher Peclet numbers may, in at least some embodiments and examples as described herein, provide improved performance and process control.

In one embodiment, the static mixer electrode may be designed to operate at a Peclet number (Pe) of at least 100, 1000, 2000, 5000, 10000, 15000, 20000, 25000, 50000, 75000, 100000, 250000, 500000, 10⁶, or 10⁷. An electrode with a static mixer function may be designed to operate at a Peclet number (Pe) of less than about 10⁸, 10⁷, 10⁶, 500,000, 250,000, 100,000, 75,000, 50,000, 25,000, 20,000, 15,000, 10,000, 5,000, 2,000, or 1,000. An electrode with a static mixer function can be designed to operate at a Pe number ranging from about 10³ to 10⁸, from 10³ to 10⁷, or from 10⁴ to 10⁶. The static mixer electrode may be designed to operate at a Pe between any two of the above upper and/or lower limits.

The % volumetric displacement of an electrode with a static mixer function relative to the electrode flow channel body can range from about 1 to 90, 5 to 70, 10 to 30, or 5 to 20. The % volume displacement of an electrode with a static mixer function relative to The body of the electrode flow channel can be less than 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%, or 5%. Volumetric displacement in % of an electrode with a static mixer function relative to the body of the electrode flow channel can be more than 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 50%, 60%, 70% or 80%. Volumetric displacement in % can be adjusted within the range of any two of the above "less" and "more" values.

Static mixer electrode configurations can be designed to enhance the heat and mass transfer characteristics of the reactor, such as reducing the temperature difference at the exit of the cross section. Heat and mass transfer at a static mixer electrode may, for example, form a cross-sectional or cross-flow temperature profile that has a temperature difference of less than about 20°C/mm, 15°C/mm, 10°C/mm, 9°C/mm, 8°C/mm, 7°C/mm, 6°C/mm, 5°C/mm, 4°C/mm, 3°C/mm, 2°C/mm, or 1 °C/mm.

The static mixer electrode or its substrate may be configured such that, in use, the pressure drop (i.e., pressure difference or back pressure) across the static mixer electrode (in Pa/m) is between about 0.1 and 1000000 Pa/m (or 1 MPa/m), including at any value and range of any values between them. For example, the pressure drop across a static mixer electrode (in Pa/m) may be less than about 500,000, 250,000, 100,000, 50,000, 10,000, 5000, 1000, 750, 500, 250, 100, 75, 50, 25 , 20, 15, 10, or 5 Pa/m. For example, the pressure drop across the static mixer electrode (in Pa/m) may be at least about 10, 100, 1000, 5000, 10000, 50000, 100000, or 250000. The pressure drop across the static mixer electrode ( in Pa/m) can be adjusted between any two of the above upper and/or lower limits. For example, in one embodiment, the pressure drop across the static mixer electrode (in Pa/m) may be between about 10 and 250,000, 100 and 100,000, or 1,000 and 50,000. The static mixer electrode may be configured to providing a lower pressure drop relative to a particular flow rate. In this regard, the static mixer function electrode, reactor, system, and methods as described herein can be implemented with parameters suitable for industrial applications. The above pressure drops can be maintained where the volume flow rate is at least 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6 , 7, 8, 9, 10, 20, 30, 40, 50 ml/min.

In one embodiment, static mixer electrodes can be designed to operate at a volumetric flow rate of at least 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4 .5, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 75, 100, 125, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800 , 900, or 1000 ml/min. In another embodiment, the volume flow rate may be less than about 1000, 900, 800, 700, 600, 500, 450, 400, 350, 300, 250, 200, 150, 100, 75, 50, 40, 30, 20, 10, or 5 ml/min. The flow rate may be in the range formed by any two of these upper and/or lower limit values, such as between about 50 and 400, 10 and 200, or 20 and 200.

An electrode with a static mixer function can be formed as a modular insert for a continuous flow electrochemical reactor or its chamber. An electrode with a static mixer function may be designed for use with a continuous flow electrochemical reactor or chamber thereof in a process line. The in-line continuous flow electrochemical reactor may be a recirculating loop reactor or a single pass reactor.

An electrode with a static mixer function can be configured using a Computational Fluid Dynamics (CFD) software package, which can be used to improve the design in terms of enhancing reactant mixing for increased contact and activation of reactants on the surface of the static mixer electrode. mixer.

The static mixer electrode may be a static mixer electrode formed using additive technology. By additively forming a static mixer electrode, optionally with catalytic and/or corrosion resistant coatings, a static mixer electrode designed for efficient mixing, heat and mass transfer, electrochemical reaction, or additional catalytic reaction can be obtained. The additive shaping method produces a static mixer electrode physically tested for reliability and performance, and optionally further redesigned and reconfigured using additive shaping technology (eg, via 3D printing). Additive shaping provides flexibility in pre-design and testing, as well as the ability to re-design and re-configure static mixer electrodes. An electron beam 3D printer or a laser 3D printer can be used. The additive material for 3D printing can be, for example, a pure metal such as iron, cobalt, nickel, copper, zinc, or an alloy such as titanium alloy powders (for example, with a diameter in the range of 45-105 micrometers), powders based on cobalt-chromium alloy (eg FSX-414 or Stellite S21), or stainless steel or aluminium-silicon alloy, or any of the nickel-based alloys (eg Inconel, Hastelloy). The particle diameters of the powders associated with laser printers are typically smaller than those used in cathode ray printers. Alternatively, the substrate may be additively fabricated from an inert material such as plastic or glass and then coated with a suitable electrically conductive material. In addition to the electrically conductive surface, the static mixer electrode or its substrate may optionally further include materials with catalytic activity, depending on the particular reaction or application desired.

Counter electrode

It will be understood that the counter electrode is electrically conductive. The counter electrode can act as an anode or cathode, depending on the direction of the applied electric current. The counter electrode may be composed of a material or configured according to any of the embodiments or examples as described above for the static mixer electrode.

It will be understood that the counter electrode may include an electrically conductive surface. The counter electrode can be made from a material capable of producing current densities on any electrode in the range of about 1 µA·m ^-2 to about 1000 A·m ^-2 . The counter electrode may include an electrically conductive material, for example, a conductive carbon material such as graphite, glassy carbon, or boron-doped diamond, metals, alloys, or intermetallic compounds in the form of powders, sheets, rods, or bars, semi-metals, or doped or narrow-gap semiconductor materials. , plated particles, conductive ceramic materials. The counter electrode may be made of a non-conductive material and covered with an electrical conductor. The non-conductive materials can be particulate non-conductive materials such as plastics, ceramic materials, glasses or minerals, thermoset resins, thermoplastic resins, and natural products such as rubber and wood. The electrically conductive coatings may be formed from metals, metal alloys, intermetallic compounds, conductive compounds, or any electrically conductive materials as described above for the counter electrode or the static mixer electrode.

Reactor and End Cap Configuration

The reactor may be formed as an assembly including a reactor vessel, a first electrode, a second electrode, a separator, and one or two optional end caps. The end caps may be designed to seal the reactor vessel, and are further optionally configured in combination with one or more of the first electrode, second electrode, separator, for structural support and centering during reactor assembly and operation.

In one embodiment, the tubular reactor may include first and second end caps, with each of the first and second end caps cooperating to secure opposite ends of the reactor vessel and to support structural members of the static mixer electrode, counter electrode, and separator in the reactor.

The end caps may be integral with the static mixer electrode and/or the counter electrode (eg, the end caps may be formed as part of one of the electrodes). The end caps may be formed as a single piece of an electrochemical flow cell or continuous flow electrochemical tubular reactor (eg, the entire electrochemical flow cell is fabricated by an additive forming process).

End caps can be created according to any other embodiments or examples thereof, as described here.

Electrochemical flow system

A system for carrying out an electrochemical reaction under continuous flow conditions may include an electrochemical flow cell or an electrochemical tubular reactor, according to any one or more aspects, embodiments, or examples as described herein.

In addition, the system may include a pump to provide a fluid stream for one or more fluid reactants and any products thereof through the reactor. The system may further include an electrical unit for applying and controlling an electrical voltage or current flowing through the electrodes to initiate an electrochemical reaction at the interface between the fluid flow and the electrodes. The system may further include a control device for controlling one or more system parameters selected from concentration, flow rate, temperature, pressure, and residence time, one or more fluid reactants, or their sources or products.

The reactor system may include a single flow cell assembly, or a plurality of assembly assemblies connected in parallel or in series. The polarities of the electrodes in each block can be connected in the same way in each cell, or in an alternating order, in which the outer electrodes are alternately anode, cathode, anode, cathode (or vice versa), and the inner electrodes are alternately cathode, anode, cathode, anode (or vice versa). The system can be tuned in any combination of these polarities. The magnitudes of voltages or currents applied to each cell in the system may be identical or may vary, and the flow rates through the cells in the system may be identical or may vary.

The reactor system may be configured and controlled to accommodate time-varying power input, such as from renewable energy sources. For example, the flow rates of the reactants may be variable according to the power available for electrolysis, so that the flow through the reactor is kept active when the power source is changed.

The aspect ratios of the reactor may be, for example, similar to those previously described for the static mixer function electrode, so that the static mixer function electrode module can be configured to be inserted into the reactor.

The reactor may include an optional heat exchanger to control the temperature of the reactor, chamber compartment, static mixer, or fluid components therein. The heat exchanger may be of a shell and tube heat exchanger design or configuration.

The present invention also provides a continuous flow electrochemical reaction system comprising:

a continuous flow electrochemical reactor comprising one or more electrodes with a static mixer function according to any of the embodiments or examples as described herein;

a pump for delivering a fluid stream for one or more fluid reactants and any products thereof through the reactor;

a control device for regulating one or more system parameters selected from reactant concentration, flow rates, current flow, input voltage, pressure, and residence time.

The system may include an optional heat exchanger to control the temperature of the reactor or fluid components therein.

The system may further include a spectrometer that can be used to identify and determine the concentrations of any one or more fluid reactants or their products.

One or more of the reactor, reactor chamber, chamber compartment, and static mixer electrode in each case may be formed in a modular form to complement each other. The system may include a plurality of reactors, which may have a similar or different internal and/or external configuration. The reactors may operate in series or in parallel, or a combination of both. It will be appreciated that the system, reactor, or each chamber compartment may include one or more inlets and outlets to provide reactants, produce products, or recycle various reactants and/or products.

It will also be appreciated that the reactor or system may be designed to recycle various reactants, sources of reactants, intermediates, or desired products introduced into or formed in the chamber compartments. The reactor or system may be formed in various designs and shapes, for example in the form of a tubular reactor. In yet another embodiment, the reactor is a single pass reactor.

The system and processes can also be combined into more complex systems, such as systems and processes including a coal gasification plant, water purification and distribution, a natural gas electrolyser and/or reformer, a chemical synthesis and purification plant, and so on.

Electrochemical Applications

An electrochemical flow reactor, an electrochemical flow cell, or a continuous flow electrochemical tubular reactor, according to any of the embodiments or examples as described herein, can be used for a variety of applications including metal recovery, recovery of heavy and valuable metals from mining effluents and effluents. industry, disinfection and purification of water (e.g. drinking water), and recovery of metals from solid wastes (e.g. sludge, mining waste, and salvaged products), and electrosynthesis of various products (e.g. gas generation, energy storage and conversion, regeneration reagents, and polymerization).

A reactor including an electrode with a static mixer function may be designed for use in a continuous flow electrochemical reaction system and process. The process may be a continuous flow process. A continuous flow process may be a recirculation loop or a single pass process. In one embodiment, the continuous flow process is a single pass process.

As mentioned above, an electrochemical reactor including an electrode with a static mixer function is capable of carrying out reactions in a continuous mode. In an electrochemical reactor, single or multi-phase input and product streams can be used. In one embodiment, the feed material (comprising one or more reactants) may be formed as a continuous fluid stream, for example, a liquid stream containing either: a) a substance as a dissolved material in a suitable solvent, or b) a liquid feed, with a co-solvent without him. It will be appreciated that the fluid stream may be formed by one or more gaseous streams, such as hydrogen gas or a source thereof. The feed material is pumped into the reactor as a pressurized stream, for example by means of a pump. In yet another embodiment, the feed material may be in the form of a suspension of solids in a fluid stream, and in yet another embodiment, the fluid reactant stream may contain solids, liquids, and gases.

In one embodiment, a process for electrochemically treating a fluid stream is provided, comprising the use of an electrochemical flow cell or a continuous flow electrochemical tubular reactor, according to any of the embodiments or examples as described herein.

The above method may be designed to remove dissolved metal ions from a fluid stream by applying direct current to the static mixer electrode and the counter electrode to form a solid deposit containing metals and/or metal compounds on the surface of the static mixer electrode. The method may be designed to recover metal from a fluid stream obtained from waste water ("tails") of the mining industry. The method may include operation in parallel and/or serial mode, as described above for the reactor system. In one embodiment, the method operates in sequential mode.

In one example, the method includes at least a first and a second continuous flow electrochemical tubular reactor, each reactor configured such that a permeable membrane separates a static mixer electrode from a counter electrode, forming an inner coaxial flow channel housing of one electrode, and an outer concentric flow channel housing. channel of the other electrode, and each flow channel has at least one inlet channel and at least one outlet channel. The method may deposit metal on the static mixer electrode of the first tubular reactor while placing the second reactor in series with reverse polarity of the electrodes to remove metal previously deposited on the static mixer electrode of the second tubular reactor.

In a further example of this above method, a first fluid stream may be introduced into the inner coaxial flow path of the first tubular reactor, and its outlet stream introduced into the outer concentric flow path of the second tubular reactor. The second fluid stream can be simultaneously introduced into the outer concentric flow channel of the first tubular reactor, and the stream exiting its outlet channel is introduced into the inner coaxial flow channel of the second tubular reactor. The first tubular reactor may operate having a first electrode with a static mixer function under reducing conditions to accumulate solid metal particles, and the second tubular reactor can operate with a second electrode with a static mixer function under oxidizing conditions to remove any metal present thereon.

Another advantage of the electrochemical flow reactor and its system according to various embodiments or examples as described here is that the electrochemical flow cell or tubular reactor does not need to be dismantled and replaced by the cathode, and provides operational flexibility when operating in series or in reverse mode. switching the current and switching the supply of various fluid streams to remove metal, metal compounds or other metal-containing products formed at the static mixer electrode as a cathode in the reduction reaction.

The present invention also provides a process for synthesizing a product by reacting one or more reactants in a fluid, the process comprising the steps of:

creating a continuous flow electrochemical reactor comprising an electrode with a static mixer function or a system according to any of the embodiments or examples as described herein;

supplying at least the first fluid reactant to the reactor through the reactant inlet;

operating the reactor, or its control device, to create a flow and conduct the reaction of at least the first fluid reactant through the electrode with the function of a static mixer;

obtaining an output stream including the reaction product of at least the first reactant.

It will be understood that various parameters and conditions used in the process, such as current flow, pressures and concentrations/amounts of materials and reactants, can be selected depending on the range of process variables, including the synthesized product, the conditions and mechanisms of the electrochemical reaction being carried out, the source reactants, or the type of reactor and materials used and their configuration. For example, differences will occur where one or more of the fluid reactants, or co-solvents (eg, inert carriers), etc., are gases, liquids, solids, or combinations thereof.

An electrochemical flow reactor can operate with current densities at any electrode in the range of 1 µA·m ^-2 to about 1000 A·m ^-2 . The current density (in A·m ^-2 ), for example, may be less than about 1000, 500, 200, 100, 50, 20, 10, 5.0, 2.0, 1.0, 0.5, 0 0.0005, 0.0001, 0.00005, 0.00002, 0.00001, 0 .000005, 0.000002, or 0.000001. The current density (in A m ^-2 ), for example, may be greater than about 0.000002, 0.000005, 0.00001, 0.00002, 0.00005, 0.0001, 0.0002, 0.0005 , 0.001, 0.002, 0.005, 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1.0, 2.0, 5.0, 10, 20, 50, 100 , 200, or 500. The current density can be adjusted to any range of two values selected from two values selected from any of the above values. It will be understood that different current densities can be used in different applications and configurations.

In some examples, voltages applied to the electrodes may be less than about 2.0, 1.8, 1.6, 1.4, 1.2, 1.0, 0.8, 0.6, 0.4, or 0.2. In some examples, voltages applied to the electrodes may be at least about 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, or 1.8. The voltages may be in a range including any two of these upper and/or lower limit values.

In one example, the performance of an electrochemical flow reactor can be measured by its recovery efficiency. Recovery efficiency includes the amount of substances (eg, contaminants), such as dissolved metal particles, present in the fluid that can be removed from the fluid by the electrochemical flow cell. In one example, recovery efficiency, measured as % of contaminant removed (or removed) from the fluid, is at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70 75 80 85 90 95 96 97 98 or 99 than about 48 hours, 36 hours, 24 hours, 12 hours, 6 hours, 3 hours, 2 hours, or 1 hour. In yet another example, substances (e.g., contaminants), such as dissolved metal particles (e.g., copper particles), can be removed from a fluid where the particles are present in the fluid at a concentration (in mol/L) of less than about 1, 0.5, 0.1, 0.05, 0.01, 0.005, 0.001, 0.0005, 0.0001, 0.00005, or 0.00001. In yet another example, substances (e.g., contaminants) such as dissolved metal particles (e.g., copper particles) can be removed from a fluid where the particles are present in the fluid at a concentration (in mol/L) of greater than about 0, 0001, 0.0005, 0.001, 0.005, 0.01, 0.05, 0.1, or 0.5. The removed substances may be between any two of these upper and/or lower limits. The above recovery efficiencies and/or recycle times may apply to any concentration of these substances (eg, contamination). For example, the performance of the reactor, system, or methods may be capable of recovering at least about 50% of dissolved metal particles from a fluid having an initial concentration of less than about 0.01 mol/L. In yet another example, recovery efficiency may be at least about 60% of dissolved metal particles from a fluid having an initial concentration of less than about 0.005 mol/L. In yet another example, recovery efficiency may be at least about 70% of dissolved metal particles from a fluid having an initial concentration of less than about 0.001 mol/L. In yet another example, recovery efficiency may be about 80% of dissolved metal particles from a fluid having an initial concentration of less than about 0.0005 mol/L. In yet another example, recovery efficiency may be about 90% of dissolved metal particles from a fluid having an initial concentration of less than about 0.0001 mol/L.

In yet another example, substances (eg, contaminants), such as dissolved metal particles (eg, copper particles), may be removed from a fluid where the particles are present in the fluid at an initial concentration (in ^ppm ) of about or less than about 1000, 750, 500, 250, 100, 75, 50, 25, 10, 5, or 1. In yet another example, substances (e.g., contaminants) such as dissolved metal particles can be removed from the fluid where the particles are present in the fluid at an initial concentration (in ^ppm ) of about or greater than about 5, 10, 25, 50, 75, 100, 250, 500, 750, or 1000. The particles to be removed may be at an initial concentration in the fluid between any two of these upper and/or lower limit values. In one example, the recovery efficiency, measured as % of contaminant recovered (or removed) from the fluid, is at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70 , 75 80 85 90 95 96 97 98 or 99 than about 48 hours, 36 hours, 24 hours, 12 hours, 6 hours, 3 hours, 2 hours, or 1 hour. The above recovery efficiencies and/or recycle times may apply to any concentration of these substances (eg, contamination). For example, the performance of the reactor, system, or methods may be capable of recovering at least about 50% dissolved metal particles from a fluid having an initial concentration of about 100 ^ppm dissolved metal particles during continuous operation of less than about 3 hours. In yet another example, recovery efficiency may be at least about 95% of dissolved metal particles from a fluid having an initial concentration of about 100 ^ppm during continuous operation of less than about 24 hours.

Temperatures (°C) in relation to the method may be in the range between -50 and 400, or any integer or range of any integers between them. For example, the temperature (°C) may be at least about -50, -25, 0, 25, 50, 75, 100, 150, 200, 250, 300, or 350. For example, the temperature (°C) may be less than than about 350, 300, 250, 200, 150, 100, or 50. The temperature can also be adjusted to almost any of these values, or in a range between any of these values, such as a range between about 0 and 250°C, from about 25 to 200 ^° C, or about 50 to 150 ^° C.

In one embodiment, the method may be executed to provide a Re value of at least 0.01, 0.1, 1, 5, 50, 100, 150, 200, 250, 300, 350, 400, 550, 600, 650, 700 , 750, 800, 850, 900, 950, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2500, 3000, 3500, 4000, 4500 , 5000, 5500, 6000, 6500 , 7000, 7500, 8000, 8500, 9000, 9500, 10000, 11000, 12000, 13000, 14000, or 15000. The method can be performed in the Re range from about 0.1 to 2000, from 1 to 1000, from 10 to 800 , or from 20 to 500. The method can be performed in the Re range from about 1000 to 15000, from 1500 to 10000, from 2000 to 8000, or from 2500 to 6000. The method can be performed in the Re range between any two of the above "by at least" values.

In one embodiment, the method can be performed at a Peclet number (Pe) of at least 100, 1000, 2000, 5000, 10000, 15000, 20000, 25000, 50000, 75000, 100000, 250000, 500000, 10⁶, or 10⁷. The method can be performed at a Peclet number (Pe) of less than about 10⁸, 10⁷, 10⁶, 500000, 250000, 100000, 75000, 50000, 25000, 20000, 15000, 10000, 5000, 2000, or 1000. The method can be performed in the Pe range of about 10³ to 10⁸, from 10³ to 10⁷, or from 10⁴ to 10⁶. The method can be executed in the Pe range between any two of the above upper and/or lower limits.

The method may cause a pressure drop (or back pressure) (in Pa/m) across the static mixer electrode in the range of about 0.1 to 1,000,000 Pa/m (or 1 MPa/m), including any value or a range of any values in between. . For example, the pressure drop (in Pa/m) across an electrode with a static mixer function may be less than about 500,000, 250,000, 100,000, 50,000, 10,000, 5,000, 1,000, 750, 500, 250, 100, 75, 50, 25, 20, 15, 10, or 5 Pa/m. For example, the pressure drop (in Pa/m) across an electrode with a static mixer function may be at least about 10, 100, 1,000, 5,000, 10,000, 50,000, 100,000, or 250,000. The pressure drop (in Pa/m) across an electrode with can be adjusted between any two of the above upper and/or lower limits by the static mixer function. For example, in one embodiment, the pressure drop (in Pa/m) across the static mixer electrode may be between about 10 and 250,000, 100 and 100,000, or 1,000 and 50,000. In this regard, the static mixer electrode, reactor, the system or methods as described herein may be configured with parameters suitable for industrial applications. The above pressure drops, or ranges thereof, can be achieved where the volumetric flow rate is at least 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4 .5, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 100, 500, 1000 ml/min.

In one embodiment, the volumetric flow rate can be obtained at a level of at least 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6 , 7, 8, 9, 10, 20, 30, 40, 50, 75, 100, 125, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800, 900, or 1000 ml /min In another embodiment, the volumetric flow rate can be obtained at a level of less than about 1000, 900, 800, 700, 600, 500, 450, 400, 350, 300, 250, 200, 150, 100, 75, 50, 40 , 30, 20, 10, or 5 ml/min. The flow rate may be between any two of these upper and/or lower limits, such as between about 50 and 400, 10 and 200, or 20 and 200.

The method may include an average residence time in the static mixer or reactor ranging from about 0.1 second to about 60 minutes. The average residence time may be, for example, less than about 60 minutes, 45 minutes, 30 minutes, 15 minutes, 10 minutes, 5 minutes, 1 minute, 30 seconds, 10 seconds, or 5 seconds. The average residence time may be, for example, more than about 1 second, 5 seconds, 10 seconds, 30 seconds, 1 minute, 5 minutes, 10 minutes, 15 minutes, 30 minutes, or 45 minutes. The average residence time may be selected within a range selected from any two of these previously mentioned values. For example, the average residence time may be in the range of 5 seconds to 10 minutes, 1 second to 5 minutes, or 1 minute to 60 minutes.

The method can provide a Faraday efficiency (current output) (% of the passed charges that took part in the reaction under discussion) of at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, less than 99, 98, 95, 90, 85, 80, 75, 70 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, or 10. The method may provide a Faraday efficiency (% of charges passed through the reaction in question) between any two of the above upper and/or lower limits.

The anolyte and/or catholyte streams may include any suitable solvent, electroactive species, and supporting electrolyte. Solute concentrations can vary from parts per billion to their solubility limits (tens of moles per liter). In addition to solutes, fluid streams can also contain multiple phases in any combination of undissolved solids (eg, solids suspended in a fluid stream), immiscible liquids, and gases. Thus, fluid streams may include aqueous and non-aqueous solvents, molecular solvents, molten salts, ionic liquids, supercritical solvents, or mixtures thereof. The solutes can be ionic, molecular, or substantially ionic pairs in solution. They may be dissolved solids, gases, miscible liquids, or mixtures thereof. Other phases present may be suspended solids or gels, organic or inorganic polymers, natural products, or mixtures thereof. They may be gases or vapors deliberately introduced or formed as a result of flow and/or electrochemical activity. In yet another example, the fluid is a liquid or a complex liquid such as a liquid containing a solution and/or suspension of solids.

In one embodiment, a method for removing substances from a fluid stream may be provided, including the use of an electrochemical flow cell or system thereof, according to any aspects, embodiments, or examples thereof, as described herein. The substances may be metal particles dissolved in the fluid stream. It will be appreciated that any of the above embodiments or examples relating to electrochemical flow cell performance may be applicable to this embodiment.

EXAMPLES

The present invention is further described by the following examples. It should be understood that the following description is for the purpose of illustrating particular embodiments only, and is not intended to be limiting to the above description.

Example 1

An electrochemical flow reactor was obtained, including a separator 200 (Figure 2), along with a liquid supply pipeline, including a peristaltic pump(s) 120 (Masterflex L/S Variable-Speed Drive w/ Remote I/O; 600 rpm) to control the flow of electrolyte into the cell, and a power supply 110 (an Autolab 302N potentiostat from Metrohm Autolab BV, Utrecht, The Netherlands) to control the applied electrochemical potential/current flowing through the cell.

Additively formed metal static mixer electrode (SME) 104, 204 as a working electrode was tightly inserted inside a tubular porous polymer separator 202 (GenPore Reading, USA) in separation mode configuration that forms the work compartment. Two channels are provided at each end of the electrode to create a fluid flow connection. Fluid entered the working compartment through these pipelines. As in all static mixers, the angular momentum of the slurry causes agitation as the slurry flows past the many sloped faces of the mixer surface. An inert tubular counter electrode 102, in this particular experiment made of glassy carbon, surrounds the working compartment at a short distance from the separator, creating a low volume counter electrode compartment and forming the outer shell of the cell. The entire assembly is sealed with two end caps 500 (Figures 4a, 4b and 4c). Channels 144 milled into the end caps allow fluid to flow into the counter electrode compartment. This configuration allows the use of different fluids in the two compartments if desired in the experiment.

The performance at which the cell operates can be estimated by comparing the current limit measured at various flow rates with the results of a test using a rotating disk electrode (RDE) in the same solution. These comparisons are useful performance indicators and are not used to draw any conclusions about the hydrodynamic conditions at the surface of the static mixer.

To evaluate the performance of two configurations of this electrochemical flow reactor, a series of experiments were performed to investigate the electrochemical reduction of ferricyanide ([Fe(CN) ₆ ] ³⁺ ) in a solution (10 ^-3 -10 ^-1 M), in a 0.5 M solution of potassium chloride in as a support electrolyte, using a platinum-coated electrode with a static mixer function (i.e., working electrode) and a glassy carbon tube (i.e., anode). A typical reduction reaction in a reactor with a split configuration was carried out as follows.

Chronoamperometric measurements were made with a step change in potential of -1.4 V, -1.6 V. -1.8 V and -2 V applied to the cell for 100 seconds, with the cell operating for the first 50 second interval of stationary mode (ie, 0 ml·min ^-1 ), and during the last 50-second interval at a constant flow rate between 10 and 400 ml·min ^-1 (Figures 7-9). The steady-state currents were recorded for all flow rates and with increasing flow rates, with the registration of an increase in current for all step changes in potential. Although the recorded currents increased with increasing potential, some gas bubbles were observed in the solution exiting the flow cell when -1.8 V and -2 V were applied. At these higher potentials, for this experimental format, in addition to reducing [Fe(CN ) ₆ ] ³⁺ , hydrogen evolution occurred at the cathode, which can complicate the analysis.

Experimental results showed that at lower electroactive ion concentrations where the reaction is mass transfer limited (ie, 0.001 and 0.01 M [Fe(CN) ₆ ] ³⁺ ), the electrochemical flow cell configuration significantly increased the reaction rate. At a higher concentration (i.e., 0.1 M [Fe(CN) ₆ ] ³⁺ ), where the reaction is controlled by mass transfer and kinetic factors (complex control), the reaction rate increase is smaller, between values from 1.5 to 3, 7 times faster when using an electrode with static mixer function.

Example 2

The efficiency of the electrochemical flow cell in removing copper ions from an acidic contaminated solution containing 10-100 ^ppm Cu ²⁺ in 0.01M H ₂ SO ₄ was evaluated using a stainless steel static mixer electrode (i.e., working electrode) and glassy carbon (ie, anode) tubes, at flow rates ranging from 10 to 1000 ml·min ^-1 , in an electrochemical flow cell in a split configuration embodiment. As shown in Figure 10, as the flow rate increases beyond 50 ml·min ^-1 , the removal efficiency decreases, due to the reduction in the residence time of electroactive ions on the surface of the working electrode to complete the reduction reaction (Figures 10a and 10b). On the other hand, increasing the flow rate increased the charge passing through the working electrode and correspondingly increased the current output (Figures 10c and 10d). However, increasing the flow rate is effective up to the point where the efficiency is reduced due to the reduced residence time of the electroactive ions on the electrode surface.

Example 3

Extensive electrolysis experiments were also performed to show how efficiently an electrochemical flow cell can remove copper ions from a fixed volume of contaminated aqueous solution. Two liters of a copper-contaminated aqueous solution (ie, 100 ^ppm CuSO ₄ ·4H ₂ O in 0.01M H ₂ SO ₄ ) was treated using an electrochemical flow cell at a constant flow rate of 50 ml·min ^-1 for 24 hours. Optical imaging and SEM/EDS analysis results confirmed copper ion deposition on the working electrode with static mixer function (Figure 11), and ICP-MS (Inductively Coupled Plasma Mass Spectrometry) analysis results showed that 99, 7% reduction in copper concentration over 24 hours in an electrochemical flow cell with split configurations (Figure 12).

Claims (39)

1. Electrochemical flow cell, including: reaction chamber; first electrode; second electrode; And a separator placed between the first and second electrodes, wherein the separator at least partially forms a first channel within the reaction chamber configured to receive a flow of the first fluid in contact with the first electrode, and a second channel within the reaction chamber configured to receive the flow a second fluid in contact with the second electrode, wherein the separator includes a permeable membrane configured to provide electrical communication between the first and second electrodes through the fluid streams while limiting fluid exchange between the fluid streams, and wherein the first electrode is a static mixer function electrode comprising an electrically conductive portion of the static mixer forming a plurality of separating structures configured to separate the first fluid stream into a plurality of distinct substreams at a plurality of locations along the length of the first electrode. 2. Cell according to claim 1, wherein the electrochemical flow cell is a continuous flow tubular reactor. 3. The cell of claim 2 wherein the static mixer function electrode is aligned substantially along the axis of the continuous flow tubular reactor. 4. Cell according to any one of paragraphs. 1-3, in which the static mixer function electrode includes an electrically conductive substrate. 5. Cell according to claim 4, wherein the substrate is a metal or a metal alloy. 6. Cell according to any one of paragraphs. 1-5, in which the static mixer electrode includes an electrically conductive coating. 7. Cell according to any one of paragraphs. 1-6, wherein the static mixer electrode includes an electrically conductive composite substrate forming a plurality of flow sections configured to enhance mass transfer and random advection. 8. Cell according to any one of paragraphs. 1-7, in which the diameter of the static mixer section of the first electrode may be approximately equal to the diameter of the first channel. 9. Cell according to any one of paragraphs. 1-8, in which the first electrode is placed in contact with the separator. 10. Cell according to any one of paragraphs. 1-9, in which the separator and the second electrode are placed concentrically and coaxially with the central longitudinal axis of the first electrode. 11. Cell according to any one of paragraphs. 1-10, in which the separator and the second electrode are substantially cylindrical. 12. Cell according to any one of paragraphs. 1-11, in which the second electrode forms at least part of the wall of the reaction chamber. 13. Cell according to any one of paragraphs. 1-12, wherein the first electrode, including the static mixer portion, is operable within the first channel to create a volumetric flow rate for the first fluid flow of at least about 0.1 ml/min. 14. Electrochemical flow system, including at least the first electrochemical flow cell according to any one of paragraphs. 1-13. 15. The system according to claim 14, further comprising: the second electrochemical flow cell according to any one of paragraphs. 1-13; And a plurality of flow conduits connecting the first electrochemical flow cell to the second electrochemical flow cell such that the first channel of the first electrochemical flow cell is in fluid communication with the second channel of the second electrochemical flow cell and the second channel of the first electrochemical flow cell is in fluid communication with the first channel of the second electrochemical flow cell. 16. The system according to claim 14 or 15, further comprising: a pump for creating a fluid flow of the fluid streams; a power source for regulating the current flowing through the electrodes, or the voltage applied to them; a control device for regulating one or more system parameters including concentration, flow rate, temperature, pressure, and residence time. 17. A method for electrochemical processing of a fluid stream, including the use of an electrochemical flow cell according to any one of paragraphs. 1-13, or systems according to any one of paragraphs. 14-16 introducing a first process fluid stream into the first channel of the electrochemical flow cell and obtaining a treated effluent stream including the reaction product. 18. The method of claim 17 wherein the first and second fluid streams comprise liquids. 19. The method of claim 17 or 18 for treating wastewater, removing dissolved metal ions from a fluid stream, or removing metal from a fluid stream. 20. The method of claim 17 or 18 for removing dissolved metal particles from the first fluid stream, wherein the metal particles are removed at the surface of the static mixer portion of the first electrode. 21. The method according to any one of paragraphs. 17-20, in which the electrochemical flow cell, including the first electrode containing the section of the static mixer, is configured to enhance chaotic advection by dividing the flow of the first fluid by more than 200 m ^-1 , corresponding to the number of cycles of dividing the flow of the first fluid within a given length along section of the static mixer of the first electrode. 22. The method according to any one of paragraphs. 17-21, in which an electrochemical flow cell including a first electrode containing a static mixer section is configured to provide a Peclet number (Pe) of at least about 10,000. 23. The method according to any one of paragraphs. 17-22, wherein the electrochemical flow cell is configured to provide a volumetric flow rate for the first fluid stream of at least about 0.1 ml/min. 24. The method according to any one of paragraphs. 17-23, wherein the first fluid stream includes dissolved metal particles at a concentration (mol/L) of less than about 0.01. 25. The method according to any one of paragraphs. 17-24, wherein the electrochemical flow cell is configured to be effective in removing at least 90% of the contamination or metal particles in the first fluid stream of the contamination or metal particles originally present in the first fluid stream. 26. The method according to any one of paragraphs. 17-25, wherein the electrochemical flow cell is configured to provide current densities at the static mixer electrode and the counter electrode in the range of 1 µA m ^-2 to about 1000 A m ^-2 . 27. The method according to any one of paragraphs. 17-26, including the operation of the first and second electrochemical flow cells according to any one of paragraphs. 1-13, wherein a plurality of flow conduits connect the first electrochemical flow cell to the second electrochemical flow cell such that the first conduit of the first electrochemical flow cell is in fluid communication with the second conduit of the second electrochemical flow cell, and the second conduit of the first electrochemical flow cell is in in fluid communication with the first channel of the second electrochemical flow cell. 28. The method of electrochemical synthesis of the product, including the use of an electrochemical flow cell according to any one of paragraphs. 1-13 or systems according to any one of paragraphs. 14-16 reacting a first fluid stream including one or more reactants in a first channel of an electrochemical flow cell and producing an output stream including a reaction product.

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