CA3037199A1 - Anode apparatus and methods regarding the same - Google Patents

Abstract

In some embodiments, an anode apparatus comprises: (a) an anode body comprising at least one outer sidewall, wherein the outer sidewall is configured to define a shape of the anode body, and to perimetrically surround a hole in the anode body, wherein the hole comprises an upper opening in a top surface of the anode body and wherein the hole axially extends into the anode body; (b) a pin comprising: a first end and a second end opposite the first end, wherein the second end extends downward into the upper end of the anode body and into the hole of the anode body; and (c) a sealing material configured to cover at least a portion of at least one of the following: (1) an inner sidewall of the anode body; (2) the top surface of the anode body; (3) the pin; and (4) the anode support.

Description

ANODE APPARATUS AND METHODS REGARDING THE SAME
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. provisional application No.
62/396,583, filed September 19, 2016, which is herein incorporated by reference in its entirety BACKGROUND

[0002] An inert anode is electrically connected to the electrolytic cell, such that a conductor rod is connected to the inert anode in order to supply current from a current supply to the inert anode, where the inert anode directs current into the electrolytic bath to produce non-ferrous metal (where current exits the cell via a cathode). In some embodiments, during operation of the cell, corrosive bath and/or vapor interacts with the anode assembly and can impact the effectiveness and longevity of the anode assembly (e.g. by weakening the mechanical connection, and/or increasing resistivity at the electrical connection).
FIELD OF THE INVENTION

[0003] Generally, the instant disclosure is directed towards an inert anode apparatus. More specifically, the instant disclosure is directed towards an inert anode apparatus configured to reduce, prevent, and/or eliminate corrosion of the pin and/or anode material (e.g. by corrosive vapors and/or molten electrolyte) in an electrolysis cell.
SUMMARY OF THE DISCLOSURE

[0004] Without being bound by a particular mechanism or theory, it is believed that one or more embodiments of the anode-pin-protective sealing material connection in the instant disclosure provide enhanced corrosion resistance to the anode assembly when measured in at least one of the following locations: (a) at the pin, inside the hole in the anode body; (b) at the anode body, along the inner diameter of the hole for the anode pin; and/or (c) in the vapor zone Page 1 of 38

5 PCT/US2017/052289 where the pin extends above the anode body (i.e., above the bath, and/or in the refractory package).
[0005] Without being bound by a particular mechanism or theory, it is believed that when the sealing material is utilized in the anode assembly, it provides protection to (1) mechanical attachment site of the anode to pin and/or (2) the anode assembly components (e.g. pin, anode body, filler material, cement material) as the sealing material is configured to accept reactive fluoride species that are present in situ in the bath and/or bath vapor.
Without being bound by a particular mechanism or theory, it is believed that by undergoing the chemical transformation to accept the fluoride species, the sealing material is transformed (at least partially) from a solid to a liquid material. In some embodiments, a sealing material is configured to extend between the inner surface of the hole in the anode body and the outer diameter of the pin.

[0006] In one aspect of the instant disclosure, an anode assembly is provided, comprising: an anode support; and an anode apparatus mechanically attached to the anode support, wherein the anode apparatus comprises: (a) an anode body comprising at least one outer sidewall, wherein the outer sidewall is configured to define a shape of the anode body, and to perimetrically surround a hole in the anode body, wherein the hole comprises an upper opening in a top surface of the anode body and wherein the hole axially extends into the anode body; (b) a pin comprising: a first end connected to a current supply, and a second end opposite the first end, wherein the second end extends downward into the upper end of the anode body and into the hole of the anode body; and (c) a sealing material comprising an aggregate and a matrix, wherein the sealing material is configured to cover at least a portion of at least one of the following: (1) an inner sidewall of the anode body; (2) the top surface of the anode body; (3) the pin; and (4) the anode support.
Page 2 of 38

[0007] In some embodiments of the instant disclosure, the sealing material comprises at least one of: water, polymers, organics, dispersants, or diluents.

[0008] In some embodiments of the instant disclosure, a sealing material is configured to cover at least a portion of at least one of the following: (1) an inner sidewall of the anode body;
(2) the pin; and (3) a filler material.

[0009] In some embodiments of the instant disclosure, the first end of the pin is configured to be retained within an anode support.

[0010] In some embodiments of the instant disclosure, the filler is retained in the hole between the inner sidewall of the anode body and the pin.

[0011] In some embodiments of the instant disclosure, the sealing material is configured to enclose the conductive filler into the anode body between the inner sidewall of the anode body and the pin.

[0012] In some embodiments of the instant disclosure, the sealing material is cast in place.

[0013] In some embodiments of the instant disclosure, the sealing material is pre-cast and screwed into the anode body.

[0014] In some embodiments of the instant disclosure, the sealing material is sintered into place during the sintering of the green form anode body into the final anode body.

[0015] In some embodiments of the instant disclosure, the sealing material is retained above the top surface of the anode body.

[0016] In some embodiments of the instant disclosure, the sealing material is retained in the hole.

[0017] In some embodiments of the instant disclosure, above the top surface of the anode body includes extending along the pin.
Page 3 of 38

[0018] In some embodiments of the instant disclosure, above the top surface of the anode body includes extending along the pin and into the anode support.

[0019] In some embodiments of the instant disclosure, above the top surface includes extending across the top surface of the upper portion of the anode body.

[0020] In some embodiments of the instant disclosure, above the top surface includes extending across the top surface and extending down around the outer sidewall of the anode body.

[0021] In some embodiments of the instant disclosure, the sealing material is applied to the anode hole between the pin and the inner surface of the anode body in a gradient, such that the concentration of sealing material varies in a radial direction.

[0022] In some embodiments of the instant disclosure, the gradient is configured such that the concentration of sealing material is higher adjacent to the pin as compared to adjacent to the inner surface of the anode body.

[0023] In some embodiments of the instant disclosure, the gradient is configured such that the concentration of sealing material is lower adjacent to the pin as compared to adjacent to the inner surface of the anode body.

[0024] In some embodiments of the instant disclosure, the sealing material is applied to the anode hole between the pin and the inner surface of the anode body in a gradient, such that the concentration of sealing material varies in a lateral direction.

[0025] In some embodiments of the instant disclosure, the gradient is configured such that the concentration of sealing material is higher adjacent to the upper end as compared to adjacent to the lower end of the anode body.
Page 4 of 38

[0026] In some embodiments of the instant disclosure, the gradient is configured such that the concentration of sealing material is lower adjacent to the upper end as compared to adjacent to the lower end of the anode body.

[0027] In some embodiments of the instant disclosure, the sealing material is configured with a higher concentration at a position adjacent to the bath-vapor interface, as compared to either the upper end in the vapor phase or the lower end in the bath of the anode body.

[0028] In some embodiments of the instant disclosure, the concentration of sealing material from a position just below the bath-vapor interface to a position adjacent to the upper end of the anode is higher than the portion of sealing material in the submerged portion of the anode body.

[0029] In one aspect of the instant disclosure, an electrolysis cell, comprising: a cell structure comprising a cell bottom and a cell sidewall, wherein the cell sidewall is configured to perimetrically surround the cell bottom and extend in an upward direction from the cell bottom to define a control volume, wherein the control volume is configured to retain a molten electrolyte bath; and an anode assembly configured to direct current into the molten electrolyte bath, wherein the anode assembly comprises: an anode support; and an anode apparatus mechanically attached to the anode support, wherein the anode apparatus comprises: (a) an anode body comprising at least one outer sidewall, wherein the outer sidewall is configured to define the anode shape and to perimetrically surround a hole in the anode body, wherein the hole comprises an upper opening in the top of the anode body and wherein the hole axially extends into the anode body; and (b) an pin comprising: a first end connected to a current supply, and a second end opposite the first end, wherein the second end is configured to extend down into the upper end of the anode body and into the hole of the anode body;
and (c) a Page 5 of 38 sealing material configured to cover at least a portion of at least one of the following: an inner sidewall of the anode body; the top surface of the anode body; the pin; and the anode support.
BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Embodiments of the present invention, briefly summarized above and discussed in greater detail below, can be understood by reference to the illustrative embodiments of the invention depicted in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

[0031] Figure 1 depicts a block diagram of a generic anode assembly in accordance an embodiment of the instant disclosure.

[0032] Figure 2 depicts a schematic cut-away side view of an anode apparatus in accordance with an embodiment of the instant disclosure.

[0033] Figure 3 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0034] Figure 4 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0035] Figure 5 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0036] Figure 6 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0037] Figure 7 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.
Page 6 of 38

[0038] Figure 8 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0039] Figure 9 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0040] Figure 10 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0041] Figure 11 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0042] Figure 12 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0043] Figure 13 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0044] Figure 14 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0045] Figure 15 depicts a cut-away side view of an embodiment of an anode apparatus of the instant disclosure.

[0046] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. The figures are not drawn to scale and may be simplified for clarity. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.
DETAILED DESCRIPTION
Page 7 of 38

[0047] Figure 1 depicts a block diagram of a generic anode assembly 10 in accordance an embodiment of the instant disclosure. In some embodiments of the instant disclosure, the anode assembly 10 comprises an anode support and an anode apparatus. In some embodiments, the anode apparatus is mechanically attached to the anode support (e.g. refractory package, structural support member, combination thereof). In some embodiments, the anode apparatus comprises: an anode body, a pin, and a sealing material.

[0048] In some embodiments, the anode assembly is a part of an electrolysis cell comprising a cell structure comprising a cell bottom and a cell sidewall. In some embodiments, the cell sidewall is configured to perimetrically surround the cell bottom and extend in an upward direction from the cell bottom to define a control volume. In some embodiments, the control volume is configured to retain a molten electrolyte bath.

[0049] In some embodiments, the anode body comprises at least one outer sidewall. In some embodiments, the outer sidewall is configured to define a shape of the anode body and to perimetrically surround a hole in the anode body. In some embodiments, the hole comprises an upper opening in a top surface of the anode body and the hole axially extends into the anode body. In some embodiments, the pin comprises a first end and a second end. In some embodiments, the first end is connected to a current supply. In some embodiments, the second end is opposite the first end. In some embodiments, the second end extends downward into the upper end of the anode body and into the hole of the anode body.

[0050] In some embodiments, the sealing material is configured to cover at least a portion of at least one of the following: an inner sidewall of the anode body; the top surface of the anode body; the pin; and the anode support. In some embodiments, the sealing material is configured Page 8 of 38 to cover at least a portion of at least one of the following: an inner sidewall of the anode body;
the pin; and a filler material.

[0051] In some embodiments, the sealing material is configured to reduce, prevent, or eliminate corrosive constituents of the electrolysis process from contacting (and corroding) (1) the pin and/or (2) the mechanical attachment site of the anode body to the pin. In some embodiments, the sealing material is configured to be tailored (i.e. matched) to the composition of the anode body. In some embodiments, the sealing material is configured such that aggregate present in the sealing material is compositionally consistent with the anode body composition.
In some embodiments, the sealing material is configured to substantially overlap with the coefficient of thermal expansion of the anode body.

[0052] In some embodiments, the sealing material is inserted into the anode body (between the inside of the anode body and the pin) as a particulate material. In some embodiments, the sealing material is inserted into the anode body (between the inside of the anode body and the pin) as a liquid/slurry applied to the anode body or pin. In some embodiments, when the sealing material is inserted into/added onto the anode body, it undergoes a chemical and/or thermal cure in order to form a solid sealing material. In some embodiments, the sealing material is positioned between the pin and the anode body.

[0053] In some embodiments, a sealing material is utilized around the upper end of the anode body, surrounding the outer surface of the pin and contacting the anode body (e.g. inner portion of the hole in the anode body, top surface of the anode body, upper portion of the anode body, and/or combinations thereof). In some embodiments, the sealing material comprises a cement.
In some embodiments, the sealing material comprises a grout. In some embodiments, the sealing Page 9 of 38 material is configured to prevent corrosive vapors from entering into the inner surface of the anode body, proximal to the portion of the pin that is retained within the anode body.

[0054] In some embodiments cement includes aggregate and a binder or matrix.
In some embodiments, the aggregate is replaced with a sealing material in accordance with the instant disclosure (e.g. utilizing the commercially available binder and/or matrix).
In some embodiments, the matrix or binder is replaced with a sealing material in accordance with the instant disclosure (e.g. utilizing the commercially available aggregate). In some embodiments, the matrix or binder and aggregate is replaced with a sealing material in accordance with the instant disclosure. Some non-limiting commercial examples of binders, matrices, aggregates, and/or combinations thereof include: A1203, 5i02, MgO, CaO, or the like.

[0055] In some embodiments, the sealing material includes at least one of:
water, polymers, organics, dispersants, and/or diluents in order to promote a flowable sealing material such that the sealing material is formable/flowable into its desired location (e.g. in the anode assembly and/or anode body).

[0056] In some embodiments, the sealing material is configured to enclose the conductive filler into the anode body (i.e. between the inner sidewall of the anode body and the pin). In some embodiments, the sealing material is configured to provide a mechanical attachment of the anode body to the pin. In some embodiments, the sealing material is configured to provide structural support to the anode assembly and/or anode apparatus.

[0057] In some embodiments, the sealing material is cast in place. In some embodiments, an accelerant is utilized in combination with the sealing material in order to reduce the curing time.
In some embodiments, the sealing material is pre-cast and screwed into the anode body (e.g.
upper portion of the anode body). In some embodiments, the sealing material is sintered into Page 10 of 38 place while/during the sintering of the green form anode body into the final anode body/anode assembly (anode body, pin, and sealing material). In some embodiments, the sealing material is retained above the hole, proximal to the top surface of the upper end of the anode. In some embodiments, sealing material is retained in the hole (i.e. extending between the pin and the inner sidewall of the anode body) and above the top surface of the anode body.

[0058] In some embodiments, above the top surface of the anode body includes extending along the pin (i.e. portion of the pin that extends out of the anode body). In some embodiments, above the top surface of the anode body includes extending along the pin and into the anode support (i.e. portion of the pin that extends into the anode support, where the pin is mechanically attached). In some embodiments, above the top surface includes extending across the top surface of the upper portion of the anode body. In some embodiments, above the top surface includes extending across the top surface and extending down around the outer sidewall of the anode body (i.e. creating a collar around the upper end of the anode surface).

[0059] As used herein, "anode" means the positive electrode (or terminal) by which current enters an electrolytic cell. In some embodiments, the anodes (i.e. anode bodies) are constructed of electrically conductive materials. In some embodiments, the anode comprises an inert anode (e.g. non-reactive, dimensionally stable, and/or having a dissolution rate (e.g. at the cell operating parameters) less than that of a corresponding carbon anode).

[0060] As used herein, "anode body" means: the physical structure of the anode (e.g.
including the top, bottom, and sidewall(s)). Some non-limiting examples of anode materials include: metals, metal alloys, metal oxides, ceramics, cermets, and combinations thereof In some embodiments, the anode body is oval, cylindrical, rectangular, square, plate-shaped (generally planar), other geometrical shapes (e.g. triangular, pentagonal, hexagonal, and the like Page 11 of 38

[0061] As used herein, "anode apparatus" means the anode or positive electrode in the electrolysis cell. In some embodiments, the anode apparatus includes: the anode body and anode pin. In some embodiments, the anode apparatus includes the anode body, anode pin, and filler/sealing materials (e.g. individually, or in combination: conductive filler and/or sealing material).

[0062] As used herein, "anode assembly" means at least one anode apparatus (anode body, pin, conductive filler, and/or sealing material) and an anode support, where the at least one anode apparatus is connected (e.g. mechanically and/or electrically) to the anode support.

[0063] As used herein, "support" means a member that maintains another object(s) in place.
In some embodiments, the support is the structure that retains the anode(s) in place. In one embodiment, the support facilitates the electrical connection of the electrical bus work to the anode(s). In one embodiment, the support is constructed of a material that is resistant to attack from the corrosive bath. For example, the support is constructed of insulating material, including, for example refractory material. In some embodiments, multiple anodes are connected (e.g. mechanically and electrically) to the support (e.g. removably attached), which is adjustable and can be raised, lowered, or otherwise moved in the cell. In some embodiments, the anode support includes a refractory material (e.g. block or assembly), other bath resistant materials, rail or beam support members, vertical adjustment components and apparatuses, and/or electrical bus work.

[0064] As used herein, "electrical bus work" refers to the electrical connectors of one or more component. For example, the anode, cathode, and/or other cell components can have electrical bus work to connect the components together. In some embodiments, the electrical Page 12 of 38 bus work includes pin connectors in the anodes, the wiring to connect the anodes and/or cathodes, electrical circuits for (or between) various cell components, and combinations thereof

[0065] As used herein, "sidewall" means: a surface that forms the wall of an object.

[0066] As used herein, "perimetrically surrounding" means: surrounding the outside edge of a surface. As a non-limiting example, perimetrically surrounding includes different geometries (e.g. concentrically surrounding, circumscribing) and the like.

[0067] As used herein, "electrolyte bath" (sometimes interchangeably referred to as bath) refers to a liquefied bath having at least one species of metal to be reduced (e.g. via an electrolysis process). A non-limiting example of the electrolytic bath composition (in an aluminum electrolysis cell) includes: NaF-A1F3, NaF, A1F3, CaF2, MgF2, LiF, KF, and combinations thereof --with dissolved alumina.

[0068] As used herein, "molten" means in a flowable form (e.g. liquid) through the application of heat. As a non-limiting example, the electrolytic bath is in molten form (e.g. at least about 750 C). As another example, the metal product that forms at the bottom of the cell (e.g. sometimes called a "metal pad") is in molten form.

[0069] In some embodiments, the molten electrolyte bath/cell operating temperature is: at least about 750 C; at least about 800 C; at least about 850 C; at least about 900 C; at least about 950 C; or at least about 975 C. In some embodiments, the molten electrolyte bath/cell operating temperature is: not greater than about 750 C; not greater than about 800 C; not greater than about 850 C; not greater than about 900 C; not greater than about 950 C; or not greater than about 975 C.
Page 13 of 38

[0070] As used herein, "vapor" means: a substance that is in the form of a gas. In some embodiments, vapor comprises ambient gas mixed with caustic and/or corrosive exhaust from the electrolysis process.

[0071] As used herein, "vapor space" refers to the head space in an electrolysis cell, above the surface of the electrolyte bath.

[0072] As used herein, "interface" refers to a surface regarded as the common boundary of two bodies, spaces, or phases.

[0073] As used herein, "bath-vapor interface" refers to the surface of bath, which is the boundary of two phases, the vapor space and the liquid (molten) electrolyte bath.

[0074] As used herein, "metal product" means the product which is produced by electrolysis.
In one embodiment, the metal product forms at the bottom of an electrolysis cell as a metal pad.
Some non-limiting examples of metal products include: aluminum, nickel, magnesium, copper, zinc, and rare earth metals.

[0075] As used herein, "at least" means greater than or equal to.

[0076] As used herein, "hole" means: an opening into something.

[0077] As used herein, "pin" means: a piece of material used to attach things together. In some embodiments, the pin is an electrically conductive material. In some embodiments, the pin is configured to electrically connect the anode body to the electrical buswork in order to provide current to an electrolysis cell (via the anode). In some embodiments, a first end of the pin is configured to fit into/be retained within an anode support (e.g. anode support and at least one anode apparatus is an anode assembly)In some embodiments, the pin is configured to overlap with the anode body. In some embodiments, the pin is configured to structurally support the anode body, as it is attached to and suspended from the pin. In some embodiments, the pin is Page 14 of 38 stainless steel, nickel, nickel alloy, Inconel, or a corrosion protected steel. In some embodiments, the pin is configured to extend into the anode body (e.g. into a hole) to a certain depth, in order to provide mechanical support and electrical communication to the anode body.
In some embodiments, the length of the pin is sufficient (long enough) to provide mechanical support to the anode body and sufficient to (short enough) to prevent corrosion on the pin inside the hole (i.e. locate the pin above the bath-vapor interface) In some embodiments, the pin is oval, cylindrical, rectangular, square, plate-shaped (generally planar), other geometrical shapes (e.g. triangular, pentagonal, hexagonal, and the like).

[0078]
As used herein, "attach" means: to connect two or more things together. In some embodiments, the pin is attached to the anode body. In some embodiments, the pin is mechanically attached to the anode body by: fastener(s), screw(s), a threaded configuration (e.g.
on pin), a mating threaded configuration (e.g. on inner surface of hole in anode body and on pin), or the like. In some embodiments, the pin is attached to the anode body via welding (e.g.
resistance welding or other types of welding). In some embodiments, the pin is attached to the anode body via a direct sinter (i.e. sintering the anode body onto the pin directly).

[0079]
As used herein, "electrically conductive material" means: a material that has an ability to move electricity (or heat) from one place to another.

[0080]
As used herein, "filler" means: a material that fills a space or void between two other objects. In some embodiments, the filler is configured to connect (e.g., electrically connect) the anode body to the pin. In some embodiments, non-limiting examples of filler include: a particulate material, a liquid/slurry material, and combinations thereof. In some embodiments, the filler is incorporated/inserted into the desired location in a flowable form, which then hardens over time to yield a solid filler material.
Page 15 of 38

[0081] In some embodiments, the filler is a conductive material, also referred to as conductive filler. In some embodiments, the filler is configured to electrically connect the pin to the anode body. Non-limiting examples of electrically conductive filler materials include: iron oxides (hematite, magnetite, wustite), copper, copper alloys, nickel, nickel alloys, precious metals, (e.g., Pt, Pd, Ag, Au) and combinations thereof.

[0082] As used herein, "sealing material" means: a substance used to close or secure an object or component (e.g. in order to reduce, prevent, and/or eliminate the transmittal of vapor or liquid to the object or component). In some embodiments, the filler is configured to seal the upper portion hole in the anode body from corrosive vapors present in the vapor space. Non-limiting examples of a sealing material include: castable cement, concrete, grout, mortar, and combinations thereof.

[0083] In some embodiments, the sealing material is a substance/material that includes at least two components: (1) aggregate and (2) matrix cement (e.g., grout), where the aggregate includes large and/or fine aggregate sizes. In some embodiments, the sealing material is applied to an area in order to act as an adhesive, as it is configured to adhere components together upon hardening.

[0084] As used herein, "castable" means: a substance/material that includes at least two components: aggregate and cement, where the aggregate includes large and fine aggregate sizes.
In some embodiments, the castable is applied to an area such in order to act as an adhesive, as it is configured to adhere components together upon hardening.

[0085] As used herein, "grout" means: a castable with matrix and finer aggregate (as compared to concrete or cement). In some embodiments, the grout includes a viscosity configured to fill cracks and crevices in the anode assembly and/or anode apparatus. In some Page 16 of 38 embodiments, the grout is configured as a bonding material that hardens in place and is used to bind things together.

[0086]
As used herein, "particulate material" means: a material composed of particles. In some embodiments, the particulate material is electrically conductive. In one embodiment, the particulate material is copper shot. Other non-limiting examples of particulate materials include: precious metals (e.g. platinum, palladium, gold, silver, and combinations thereof). As non-limiting examples, the particulate material includes: metal foam (e.g. Cu foam), large or small shot (e.g., configured to fit between the pin and the anode body and/or in the anode hole), paint, and/or powder. Other sizes and shapes of particulate materials are utilizable, provided they fill the void between the pin and the anode body (or portion below the pin, in the hole of the anode body) and promote an electrical connection between the anode body and the pin to provide current to the anode.

[0087]
In some embodiments, the sealing material is configured to reduce, prevent, or eliminate corrosion from the anode apparatus (e.g. pin, anode body, conductive filler, and/or combinations thereof).

[0088]
In some embodiments, the sealing material includes aggregate that is configured as an anode-matched aggregate. In some embodiments, the sealing material is configured as an off-gas compatible aggregate (e.g., configured to react but not substantially degrade the effectiveness of the sealing material.

[0089]
As used herein, "anode-matched aggregate" (sometimes referred to as off gas compatible aggregate) means aggregate that has an overlapping performance characteristics as the anode composition. In some embodiments, anode matched aggregate is aggregate having the same compositional constituent as the anode body (e.g. hematite, magnetite).
In some Page 17 of 38 embodiments, anode matched aggregate is aggregate having a composition that is consistent with at least one major species (or compound) present in the anode (e.g. >30 wt. %). In some embodiments, anode matched aggregate is aggregate having a compound or component of an off-gas compatible aggregate (e.g. NiFe204, NiO, CuA1204, Cu0). Some non-limiting examples of aggregating sealing materials include: spinels, magnetite, hematite, copper aluminate, nickel ferrite, or tin oxide, and combinations thereof.

[0090]
In some embodiments, the sealing material comprises a castable ceramic or cermet plug, where the aggregates (or at least a portion thereof) are replaced with an anode-matched aggregate and/or an off-gas compatible aggregate as the primary seal. As a non-limiting example, the sealing material comprises a castable ceramic or cermet containing A1203, 5i02, MgO, CaO, Na2O, and combinations thereof, where at least some of the silicates and/or aluminates are replaced with an aggregate specifically tailored/matched to the anode body and/or pin material, in accordance with the instant disclosure.

[0091]
In some embodiments, the aggregate is about 40 wt. % of the sealing material (e.g. as cured). In some embodiments, the matrix/binder is about 60 wt. % of the sealing material (e.g.
as cured). In some embodiments, the aggregate is from about 5 wt. % to 100 wt.
% of the sealing material. In some embodiments, the binder/matrix is from about 5 wt. %
to 100 wt. % of the sealing material.

[0092]
In some embodiments, the percentage and/or quantity of aggregate or binder/matrix is quantified via SEM (scanning electron microscope) or EDS (energy dispersive spectroscopy), via viewing/observing a polished cross-section of sealing material. In this embodiment, EDS is configured to provide the chemical make-up of the cross-section.
Page 18 of 38

[0093] In some embodiments, the filler is conductive filler (e.g.
configured to promote electrical communication between the pin and the anode body).

[0094] In some embodiments, within the hole, where the filler is configured to extend between the inner sidewall of the anode body and the pin (e.g. beneath the sealing material).

[0095] In some embodiments, the sealing material comprises a thickness of:
from 1 mm to not greater than 50 mm.

[0096] In some embodiments, the sealing material has a thickness of: at least 1 mm; at least 2 mm; at least 3 mm; at least 4 mm; at least 5 mm; at least 6 mm; at least 7mm;
at least 8 mm; at least 9 mm; or at least 10 mm.

[0097] In some embodiments, the sealing material has a thickness of: at least about 5 mm; at least about 10 mm; at least about 15 mm; at least about 20 mm; at least about 25 mm; at least about 30 mm; at least about 35 mm; at least about 40 mm; at least about 45 mm;
or at least about 50 mm.

[0098] In some embodiments, the sealing material has a thickness of: not greater than 1 mm;
not greater than 2 mm; not greater than 3 mm; not greater than 4 mm; not greater than 5 mm;
not greater than 6 mm; not greater than 7mm; not greater than 8 mm; not greater than 9 mm; or not greater than 10 mm.

[0099] In some embodiments, the sealing material has a thickness of: not greater than about mm; not greater than about 10 mm; not greater than about 15 mm; not greater than about 20 mm; not greater than about 25 mm; not greater than about 30 mm; not greater than about 35 mm; not greater than about 40 mm; not greater than about 45 mm; or not greater than about 50 mm.
Page 19 of 38

[00100] In some embodiments, the sealing material has a thickness of: at least about 50 mm;
at least about 100 mm; at least about 150 mm; at least about 200 mm; or at least about 250 mm.
In some embodiments, the sealing material has a thickness of: not greater than about 50 mm; not greater than about 100 mm; not greater than about 150 mm; not greater than about 200 mm; or not greater than about 250 mm.

[00101] In some embodiments, the sealing material is configured as a coating applied to the anode pin. In some embodiments, the sealing material is configured as a coating to the inner surface of the anode body. In some embodiments, the sealing material is configured as a coating applied to the upper surface (e.g. top end) of the anode body.

[00102] In some embodiments, the sealing material is applied to one or more components of the anode apparatus and/or anode assembly via washing (e.g., painting) the component directly with the material.

[00103] In some embodiments, the sealing material is applied to one or more components of the anode apparatus and/or anode assembly via applying the sealing material to the component(s) as a slurry/suspension in combination with a binder or liquid.

[00104] In some embodiments, the sealing material is applied to one or more of the anode apparatus and the pin via applying/directing the aggregate into the desired located (e.g. pouring powder, particulate, or pellets), followed by adding the matrix, mechanically agitating/combining, and allowing the sealing material to set/dry.

[00105] In some embodiments, the sealing material is applied to one or more of the anode apparatus and the pin via spraying.

[00106] In some embodiments, the sealing material is applied to one or more of the anode apparatus and the pin via gunning.
Page 20 of 38

[00107] In some embodiments, the sealing material is applied to one or more of the anode apparatus and the pin via slip casting. In some embodiments, the sealing material is applied to one or more of the anode apparatus and the pin via pressure casting. In some embodiments, the sealing material is applied to one or more of the anode apparatus and the pin via vacuum casting. In some embodiments, the sealing material is applied to one or more of the anode apparatus and the pin via slurry pressing. In some embodiments, the sealing material is applied to one or more of the anode apparatus and the pin via gel casting. In some embodiments, the sealing material is applied to one or more of the anode apparatus and the pin via electrophoretic casting.

[00108] In some embodiments, the anode matched aggregate and/or off-gas compatible aggregate is present in mixed form with the sealing material, where the aggregate is from at least 1 vol. % sealing material to not greater than 99.5 vol. % sealing material.

[00109] In some embodiments, the aggregate is present in mixed form with the sealing material, where the aggregate is from at least 1 vol. % sealing material to not greater than 100 vol. % sealing material.

[00110] As non-limiting examples, the aggregate comprises: at least 1 vol.
%; at least 5 vol.
%; at least 10 vol. %; at least 15 vol. %; at least 20 vol. %; at least 25 vol. %; at least 30 vol. %;
at least about 35 vol. %; at least 40 vol. %; at least 45 vol. %; at least 50 vol. %; at least 55 vol.
%; at least 60 vol. %; at least 65 vol. %; at least 70 vol.%; at least 75 vol.
%; at least 80 vol. %;
at least 85 vol. %; at least 90 vol. %; or at least 95 vol. %; or at least 99 vol. % of the sealing material.

[00111] As non-limiting examples, the aggregate comprises: not greater than 1 vol. %; not greater than 5 vol. %; not greater than 10 vol. %; not greater than 15 vol. %;
not greater than 20 Page 21 of 38 vol. %; not greater than 25 vol. %; not greater than 30 vol. %; not greater than about 35 vol. %;
not greater than 40 vol. %; not greater than 45 vol. %; not greater than 50 vol. %; not greater than 55 vol. %; not greater than 60 vol. %; not greater than 65 vol. %; not greater than 70 vol.%;
not greater than 75 vol. %; not greater than 80 vol. %; not greater than 85 vol. %; not greater than 90 vol. %; or not greater than 95 vol. %; or not greater than 99 vol. %
of the sealing material.

[00112] In some embodiments, a mixture of anode matched aggregate and/or off-gas compatible aggregate and sealing material includes an amount of aggregate which is sufficient to maintain the ability of the sealing material to adhere components of the anode apparatus (e.g., anode body to pin) and/or anode assembly together (e.g., pin to anode support).

[00113] In some embodiments, the sealing material is applied to the anode hole (i.e. between the pin and the inner surface of the anode body) in a gradient, such that the concentration of sealing material (with anode-matched aggregate and/or off-gas compatible aggregate) varies in a radial direction (i.e. differs from a position adjacent to the pin vs. a position adjacent to the anode sidewall).

[00114] In one embodiment, the gradient is configured such that the concentration of sealing material is (with anode-matched aggregate and/or off-gas compatible aggregate) higher adjacent to the pin as compared to adjacent to the inner surface of the anode body.

[00115] In one embodiment, the gradient is configured such that the concentration of sealing material (with anode-matched aggregate and/or off-gas compatible aggregate) is lower adjacent to the pin as compared to adjacent to the inner surface of the anode body.

[00116] In some embodiments, the sealing material is applied to the anode hole (i.e. between the pin and the inner surface of the anode body) in a gradient, such that the concentration of Page 22 of 38 sealing material varies in a lateral direction (i.e. differs from a position adjacent to the opening of the hole/upper surface of the anode body as compared to a position adjacent to the lower end of the anode body).

[00117] In one embodiment, the gradient is configured such that the concentration of sealing material is higher adjacent to the upper end as compared to adjacent to the lower end of the anode body.

[00118] In one embodiment, the gradient is configured such that the concentration of sealing material is lower adjacent to the upper end as compared to adjacent to the lower end of the anode body.

[00119] In some embodiments, the sealing material is configured with a higher concentration at a position adjacent to the bath-vapor interface, as compared to either the upper end (in the vapor phase) or lower end (in the bath) of the anode body.

[00120] In some embodiments, the concentration of sealing material from a position just below the bath-vapor interface to a position adjacent to the upper end of the anode is higher than the portion of (anode-matched aggregate and/or off-gas compatible aggregate in the) sealing material in the submerged portion of the anode body (e.g. submerged below the bath-vapor interface).

[00121] Figures 2-15 depict schematic cut-away side view of an exemplary anode apparatus in accordance with some embodiments of the instant disclosure. Figure 2 depicts an anode apparatus wherein the sealing material 50 covers a portion of the pin 12 in vapor space 24, the opening 32 and an entire top surface of the anode body 30. Figure 3 depicts an anode apparatus wherein the sealing material 50 covers an entirety of the pin 12 in vapor space 24, the opening 32 and a portion of the top surface of the anode body 30. Figure 4 depicts an anode apparatus Page 23 of 38 wherein the sealing material 50 covers a portion of the pin 12 in vapor space 24, the opening 32, and a portion of the top surface of the anode body 30. Figure 5 depicts an anode apparatus wherein the sealing material 50 covers an entirety of the pin 12 above the top surface of the anode body 30 (i.e. within the vapor space 24 and refractory portion 18), the opening 32, and a portion of the top surface of the anode body 30.

[00122] Figure 6 depicts an anode apparatus wherein the sealing material 50 covers an entirety of the pin 12 in vapor space 24, the opening 32 and an entire top surface of the anode body 30. In Figure 6, the sealing material 50 extends beyond a peripheral edge of the top surface of the anode body and covers a portion of the sidewall 40 of the anode body 30. Figure 7 depicts an anode apparatus wherein the sealing material 50 covers a portion of the pin 12 in vapor space 24, the opening 32, and an entire top surface of the anode body 30. In Figure 7, the sealing material 50 extends beyond a peripheral edge of the top surface of the anode body and covers a portion of the sidewall 40 of the anode body 30.

[00123] Figure 8 depicts an anode apparatus wherein the sealing material 50 covers an entirety of the pin 12 in vapor space 24. The sealing material 50 covers opening 32 and an entire top surface of the anode body 30. The sealing material 50 extends beyond a peripheral edge of the top surface of the anode body and covers a portion of the sidewall 40 of the anode body 30. Sealing material 50 is also disposed between the vapor space 24 and the refractory 18 to prevent corrosive chemicals from corroding exposed portions of the pin 12 (i.e. not covered by sealing material 50).

[00124] Figure 9 depicts an anode apparatus wherein the sealing material 50 covers a portion of the pin 12 in vapor space 24, the opening 32, and an entire top surface of the anode body 30.
The sealing material 50 extends beyond a peripheral edge of the top surface of the anode body Page 24 of 38 and covers a portion of the sidewall 40 of the anode body 30. A portion of the pin 12 in the vapor phase 24 is not covered by sealing material 50. Sealing material 50 is also disposed between the vapor space 24 and the refractory 18 to prevent corrosive chemicals from corroding exposed portions of the pin 12 in the refractory 18.

[00125] Figure 10 depicts an anode apparatus wherein the sealing material 50 covers an entirety of the pin 12 in vapor space 24. The sealing material 50 covers opening 32 and an entire top surface of the anode body 30. The sealing material 50 does not extend beyond a peripheral edge of the top surface of the anode body to cover a portion of the sidewall 40 of the anode body 30. Sealing material 50 is also disposed between the vapor space 24 and the refractory 18 to prevent corrosive chemicals from corroding exposed portions of the pin 12 (i.e.
not covered by sealing material 50).

[00126] Figure 11 depicts an anode apparatus wherein the sealing material 50 covers a portion of the pin 12 in vapor space 24, the opening 32, and an entire top surface of the anode body 30.
The sealing material 50 extends beyond a peripheral edge of the top surface of the anode body and covers a portion of the sidewall 40 of the anode body 30. The sealing material extends down the sidewall 40 of the anode body 30 proximate to the interface 22.

[00127] Figure 12 depicts an anode apparatus wherein the sealing material 50 covers a portion of the pin 12 in vapor space 24, the opening 32 and an entire top surface of the anode body 30.

[00128] Figure 13 depict an anode apparatus wherein the sealing material 50 covers a portion of the pin 12 in vapor space 24, the opening 32 and an entire top surface of the anode body 30.
The sealing material is also disposed within the hole 34 to cover a portion of the pin 12 within the anode body 30. The sealing material 50 covers a portion of the pin 12 within the anode body 30 that is above the interface 22.
Page 25 of 38

[00129] Figure 14 depicts an anode apparatus wherein the sealing material 50 is disposed within the hole 34 to cover a portion of the pin 12 within the anode body 30.
The sealing material 50 covers a portion of the pin 12 within the anode body 30 that is above the interface 22.

[00130] Figure 15 depicts an anode apparatus wherein the sealing material 50 is disposed within the hole 34 to cover a portion of the pin 12 within the anode body 30.
The sealing material 50 covers a portion of the pin 12 within the anode body 30 that is above the interface 22. A filler material is disposed within the hole 34 below the sealing material 50.

[00131] Reference will now be made in detail to prophetic examples, which (in combination with the accompanying drawings and previous descriptions thereof) at least partially assist in illustrating various pertinent embodiments of the present invention.

[00132] Example: Prophetic Anode Manufacture:

[00133] Non-limiting examples of producing the anode body include: press sintering, fuse casting, and casting, which is disclosed in corresponding US Patent 7,235,161, which contents are incorporated by reference herein by their entirety.

[00134] Once the anode body is formed, the pin and filler materials, if being used, are incorporated into the anode body. For example, if a filler (e.g. conductive filler) is utilized, the pin is placed in the hole of the anode body and filler (e.g. in the form of particulate material) is inserted into the void between the pin and the inner surface of the hole in the anode body. Then the sealing material (i.e., in order to provide a mechanical attachment and/or seal the pin and/or filler material into the hole in the anode body), is added to the upper end of the anode body. In some embodiments, the sealing material is configured to extend at least partially into the hole in the anode body. In some embodiments, the sealing material is configured to sit on top of the Page 26 of 38 anode body, proximal to the upper end of the hole, and surrounding the pin as it extends upward from the anode body. In some embodiments, the sealing material is placed on top of the anode body in a position surrounding the pin.

[00135] In some embodiments, the sealing material is configured to extend a portion of the way into the hole at the upper end of the anode. In some embodiments, the sealing material is configured to cover the top portion of the anode body. In some embodiments, the sealing material is configured to contact at least a portion of the outer perimetrical sidewall of the anode body. In some embodiments, the sealing material is configured to contact the pin, the inner portion of the anode body (hole), the upper portion/top surface of the anode body, and the upper portion of at least a portion of the outside perimetrical wall of the anode body.

[00136] While various embodiments of the present invention have been described in detail, it is apparent that modifications and adaptations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present invention.

[00137] Prophetic Comparative Example:

[00138] Two anode assemblies (AA1 = prior art and AA2 = an embodiment in accordance with the instant disclosure) are made with: the same anode body dimensions and composition in accordance with that set out in disclosures of US Patent Nos. 7,507,322 and 7,235,161; the same pin material (copper or copper alloy); and different sealing materials.

[00139] In AA1 the first instance (prior art), the sealing material is in accordance with the disclosure of US 7,169,270. In the second instance (instant disclosure), the sealing material has wt. % to 100 wt. % the sealing material is a castable ceramic or cermet containing A1203, 5i02, MgO, CaO, Na2O, and combinations thereof, where at least some of the silicate and/or Page 27 of 38 aluminate aggregates in the sealing material (e.g. castable ceramic) are replaced with a magnetite aggregate (e.g. anode-matched/anode compatible aggregate), configured with comparable sizing as the aggregate appropriate sizing as the aggregate in the prior art run.

[00140] Both anode assemblies are configured as the embodiment shown in Figure 2. Both anode assemblies were incorporated into an aluminum electrolysis cell and operated as electrodes (anodes) extending across the bath-vapor interface for a sufficient length of time in order to evaluate whether any reactions occur as a result of the interaction of the reactive species present in the vapor space of the cell with the sealing material and/or components thereof.

[00141] Anode assemblies are pulled out of the cell and evaluated in order to evaluate and/or quantify corrosion on the various anode apparatus components (e.g. sealing material). It will be found that the sealing material of AA2, i.e. sealing material with aggregate tailored (i.e.
matched) to the anode body, performed better (exhibits less corrosion) than the prior art sealing material. Also, it will be found that the pin of AA2 performed better (exhibits less corrosion) than the pin of AA1 (the prior art anode apparatus).

[00142] Without being bound by a particular mechanism or theory, it is believed that during cell operating conditions (i.e. at elevated temperature and in a corrosive environment in the vapor space, which contains reactive fluoride gas, oxygen gas, and/or other reactive vapor species), the silica (e.g. SiO2 present as aggregate in the sealing material) creates pockets of reactive silicates available to interact with the reactive species present in the vapor space.

[00143] Without being bound by a particular mechanism or theory, it is believed that the reactive silicates in the aggregates of the sealing material (i.e. AA1) will react with fluoride gas present in the vapor space of the cell, in turn creating silicon tetrafluoride, which is in turn corrosive to the pin. Without being bound by a particular mechanism or theory, it is believed Page 28 of 38 that as the reactive silicon fluoride species further interacts/reacts with the pin, pockets or holes are created in the sealing material (i.e. reducing the mechanical strength/structural support of the sealing material, and yielding pores/holes where the reactive species can further penetrate into and react with the sealing material, or other components of the anode apparatus. Without being bound by a particular mechanism or theory, as the silicon fluoride species react with the pin materials, initiation sites of corrosion occur on the pin and the structural integrity of the anode apparatus and/or the electrical efficiency of this component are further reduced).

[00144] Without being bound by a particular mechanism or theory, it is believed that during cell operating conditions (i.e. at elevated temperature and in a corrosive environment in the vapor space, which contains reactive fluoride gas, oxygen gas, and/or other reactive vapor species), the magnetite aggregate (e.g. SiO2 and/or A1203 replacement in the sealing material) creates pockets of aggregate tailored to not undergo significant reactions with the reactive species (and thus, will not form pores in the sealing material and/or further attribute to pin corrosion).

[00145] Without being bound by a particular mechanism or theory, it is believed that the reactive silicates in the aggregates of the sealing material (i.e. AA1) will react with fluoride gas present in the vapor space of the cell, in turn creating silicon tetrafluoride, which is in turn corrosive to the pin.

[00146] Various ones of the inventive aspects noted hereinabove may be combined to yield inert anode apparatuses having a pin which provides a mechanical and electrical connection to the anode body, where the pin extends down into the hole of the anode body and is positioned such that the lower end of the pin is located above the vapor-bath interface.
Page 29 of 38

[00147] These and other aspects, advantages, and novel features of the invention are set forth in part in the description that follows and will become apparent to those skilled in the art upon examination of the following description and figures, or may be learned by practicing the invention.
Page 30 of 38 Reference Numbers Anode Assembly 10 Pin 12 First end 14 Second end 16 Anode support 18 Current supply 20 Bath-vapor interface 22 Vapor space 24 Bath 26 Anode apparatus 28 Anode body 30 Upper opening 32 Anode inner sidewall (defining the hole) 34 Upper end of anode 36 Lower end of anode 38 Anode outer sidewall 40 Conductive filler 42 Particulate (conductive filler) material 44 Liquid/Slurry (conductive filler) material 46 Top surface of anode 48 Sealing material 50 Page 31 of 38 Aggregate 52 (large and/or small fines, e.g., aggregate particulate, powder) Matrix/Binder material 54 Page 32 of 38

Claims (24)

WE CLAIM:

1. An anode assembly, comprising:
an anode support; and an anode apparatus mechanically attached to the anode support, wherein the anode apparatus comprises:
(a) an anode body comprising at least one outer sidewall, wherein the outer sidewall is configured to define a shape of the anode body, and to perimetrically surround a hole in the anode body, wherein the hole comprises an upper opening in a top surface of the anode body and wherein the hole axially extends into the anode body;
(b) a pin comprising:
a. a first end connected to a current supply, and b. a second end opposite the first end, wherein the second end extends downward into the upper end of the anode body and into the hole of the anode body; and (c) a sealing material comprising an aggregate and a matrix, wherein the sealing material is configured to cover at least a portion of at least one of the following:
(1) an inner sidewall of the anode body;
(2) the top surface of the anode body;
(3) the pin; and (4) the anode support.

2. The anode assembly of claim 1, wherein the sealing material comprises at least one of:
water, polymers, organics, dispersants, or diluents.

3. The anode assembly of claim 1, wherein a sealing material is configured to cover at least a portion of at least one of the following: (1) an inner sidewall of the anode body; (2) the pin; and (3) a filler material.

4. The anode apparatus of claim 1, wherein, the first end of the pin is configured to be retained within an anode support.

5. The anode apparatus of claim 1, wherein the filler is retained in the hole between the inner sidewall of the anode body and the pin.

6. The anode apparatus of claim 1, wherein the sealing material is configured to enclose the conductive filler into the anode body between the inner sidewall of the anode body and the pin.

7. The anode apparatus of claim 1, wherein the sealing material is cast in place.

8. The anode apparatus of claim 1, wherein the sealing material is pre-cast and screwed into the anode body.

9. The anode apparatus of claim 1, wherein the sealing material is sintered into place during the sintering of the green form anode body into the final anode body.

10. The anode apparatus of claim 1, wherein the sealing material is retained above the top surface of the anode body.

11. The anode apparatus of claim 1, wherein the sealing material is retained in the hole.

12. The anode apparatus of claim 10, wherein above the top surface of the anode body includes extending along the pin.

13. The anode apparatus of claim 10, wherein above the top surface of the anode body includes extending along the pin and into the anode support.

14. The anode apparatus of claim 10, wherein above the top surface includes extending across the top surface of the upper portion of the anode body.

15. The anode apparatus of claim 10, wherein above the top surface includes extending across the top surface and extending down around the outer sidewall of the anode body.

16. The anode apparatus of claim 1, wherein the sealing material is applied to the anode hole between the pin and the inner surface of the anode body in a gradient, such that the concentration of sealing material varies in a radial direction.

17. The anode apparatus of claim 16, wherein the gradient is configured such that the concentration of sealing material is higher adjacent to the pin as compared to adjacent to the inner surface of the anode body.

18. The anode apparatus of claim 16, wherein the gradient is configured such that the concentration of sealing material is lower adjacent to the pin as compared to adjacent to the inner surface of the anode body.

19. The anode apparatus of claim 1, wherein the sealing material is applied to the anode hole between the pin and the inner surface of the anode body in a gradient, such that the concentration of sealing material varies in a lateral direction.

20. The anode apparatus of claim 19, wherein the gradient is configured such that the concentration of sealing material is higher adjacent to the upper end as compared to adjacent to the lower end of the anode body.

21. The anode apparatus of claim 19, wherein the gradient is configured such that the concentration of sealing material is lower adjacent to the upper end as compared to adjacent to the lower end of the anode body.

22. The anode apparatus of claim 19, wherein the sealing material is configured with a higher concentration at a position adjacent to the bath-vapor interface, as compared to either the upper end in the vapor phase or the lower end in the bath of the anode body.

23. The anode apparatus of claim 19, wherein the concentration of sealing material from a position just below the bath-vapor interface to a position adjacent to the upper end of the anode is higher than the portion of sealing material in the submerged portion of the anode body.

24. An electrolysis cell, comprising:
a cell structure comprising a cell bottom and a cell sidewall, wherein the cell sidewall is configured to perimetrically surround the cell bottom and extend in an upward direction from the cell bottom to define a control volume, wherein the control volume is configured to retain a molten electrolyte bath; and an anode assembly configured to direct current into the molten electrolyte bath, wherein the anode assembly comprises: an anode support; and an anode apparatus mechanically attached to the anode support, wherein the anode apparatus comprises:
(a) an anode body comprising at least one outer sidewall, wherein the outer sidewall is configured to define the anode shape and to perimetrically surround a hole in the anode body, wherein the hole comprises an upper opening in the top of the anode body and wherein the hole axially extends into the anode body; and (b) an pin comprising: a first end connected to a current supply, and a second end opposite the first end, wherein the second end is configured to extend down into the upper end of the anode body and into the hole of the anode body; and (c) a sealing material configured to cover at least a portion of at least one of the following: an inner sidewall of the anode body; the top surface of the anode body; the pin; and the anode support.