A process for transition metal oxide reduction

Abstract

The present disclosure generally relates to processes for the reduction of transition metals using alkali metals to produce reduced transition metals.

Description

TECHNICAL FIELD

[0001] The present disclosure generally relates to processes for the reduction of transition metal oxides using alkali metals to produce reduced transition metals. In particular, the disclosed processes are for the reduction of iron oxides using sodium to produce iron.BACKGROUND

[0002] Production of metals (such as zinc, iron, nickel, lead, chromium, palladium, copper and silver) is typically performed in large scale either electrochemically or / and by carbothermal reduction. As a result, it is usually very pollutive and uses non-reusable catalyst and reagents. Moreover, it is often expensive and energy consuming due to many difficulties associated with pyrometallurgical and electrochemical reduction processes. Traditional metal production plants are large and require huge capital investments for construction and operation. The commonly used smelting processes and other metals extraction processes, often conducted in several steps, are very energy intensive, producing large amounts of carbon dioxide (CO2) and other pollutants.

[0003] Numerous alternatives have been proposed for the production of high-quality iron (for example), with substantially lower environmental footprints and lower energy demands. The most sought studied concepts are electrochemical refineries and electrowinning-based technologies.

[0004] US 2020 / 0263313 discloses systems and methods for molten oxide electrolysis. Metallurgical assemblies and systems according to US 2020 / 0263313 may include a refractory vessel including sides and a base. The base may define a plurality of apertures centrally located within the base. The sides and the base may at least partially define an interior volume of the refractory vessel. The assemblies may include a lid removably coupled with the refractory vessel and configured to form a seal with the refractory vessel. The lid may define a plurality of apertures through the lid. The assemblies may also include a current collector proximate the base of the refractory vessel. The current collector may include conductive extensions positioned within the plurality of apertures centrally located within the base.

[0005] WO 2011 / 092516 discloses a method for the preparation of iron or iron alloys from iron ore, the method comprising the steps of electrolyzing dissolved iron ore in an electrolytic bath comprising at least one molten salt and optionally including dissolved metals, and separating the resulting iron metal or steel. The at least one molten salt is chosen from salts of alkali metals, alkaline earth metals and transition metals. The method of WO 2011 / 092516 comprises either an electrowinning process or a liquid / liquid metal extraction process.

[0006] U.S. Pat. No. 8,764,962 a method of extracting a target element from an oxide feedstock of the target element, the method comprising: providing a liquid oxide electrolyte comprising at least 75% by weight of one or more oxide compounds, in which the oxide feedstock is dissolved forming ionic oxygen species and ionic target element species; providing an anode comprising a metallic anode substrate wherein one element constitutes at least 50% by weight of the metallic anode substrate, and wherein the one element is more reactive with respect to oxygen than the target element, the metallic anode substrate having a solid oxide layer comprising one or more oxides selected from the group consisting of the target element, the metallic anode substrate and the electrolyte, the anode in contact with the electrolyte; providing a cathode in contact with the electrolyte; driving electrons from the ionic oxygen species in the electrolyte into the metallic substrate across the solid oxide layer thereon so as to form gaseous oxygen; and reducing the ionic target element species in the electrolyte to form a liquid of the target element at the cathode, the target element having a melting temperature greater than 1200° C.

[0007] PCT / IL2022 / 050754 discloses a process for the reduction of a transition metal oxide, the process comprising: (a) providing at least one transition metal oxide having the formula MTnOm, wherein each one of n and m is 1, 2, 3, 4, 5, 6 or 7, wherein MT is a first-row transition metal selected from: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn; (b) contacting the transition metal oxide with an alkali metal (MA) in a reactor, and adjusting the temperature within the reactor to a temperature T, to induce a two-reaction sequence of the reaction schemes I and II: I: MTnOm+2m×MA→m×MA2O+n×MT; II: MA2O→2×MA+0.5O2; so that a net reaction, III, resulting from said two-reaction sequence does not consume the alkali metal, III: MTnOm→n×MT+0.5m×O2; and a resulting reaction mixture comprises a reduced transition metal, MT, or alloy thereof, the alkali metal, and optionally oxygen; wherein MA is Na or K; and wherein temperature T is above the melting point of the alkali metal and equal or above the decomposition temperature of MA2O; and (c) isolating the reduced transition metal or alloy thereof, from the reaction mixture.

[0008] A number of medium scale electrolysis-based plants / reactors have been constructed. However, none have demonstrated possessing added value over traditional smelters, with problems of construction materials, electrodes and electronic conductivity of the melt. Specifically, molten oxides and molten salts electrolysis-based reductions so far were not successful with transition metals and cannot meet the EU demand to decarbonize steel production by 2030.

[0009] Similarly, hydrogen-based reductive processes for steel and other related metal and alloys still need to overcome major technological barriers in order to meet such decarbonization demand.

[0010] There exists a long-felt need for an environmentally conscious process for metal production, which avoids electrolysis and hydrogen reduction and is energy- and cost efficient, and scalable.SUMMARY

[0011] The following embodiments and aspects thereof are described and illustrated in conjunction with compositions and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the above-described problems have been reduced or eliminated, while other embodiments are directed to other advantages or improvements.

[0012] The present invention provides processes for the production of transition metals and alloys thereof from the corresponding transition metal oxides. The present processes are simple and cost effective compared to corresponding processes for preparing transition metals (e.g., electrolysis), and results in typically high purity metals.

[0013] In is to be understood that throughout the present disclosure the term “metal” refers the zero-oxidation state of the metallic element, unless specified as a metal oxide or a constituent in metal oxides (i.e., a metal cation).

[0014] The present invention employs a two-reaction sequence, of individual reactions, which were surprisingly found to be compatible for a reaction sequence (e.g., within a shared reaction or reaction system) and produce a synergistic effect that results in a simple process, and high yield and purity, according to some embodiments. The first reaction (Reaction I) is a reduction of an iron metal oxide using a sodium metal, optionally, wherein the reaction is neat (i.e., the reaction mixture consists essentially of the transition metal oxide using and the sodium metal). Specifically, alkali metals such as sodium are known to have lower (more negative) redox potentials than transition metals such as iron, which promotes a redox reaction of Scheme I:wherein n and m are integers (e.g., 1 to 7).

[0016] Thus, the first reaction results in the desired product iron and sodium oxide, according to some embodiments. Advantageously, conducting the reaction at a temperature T, which is in the range of 100° C. to 5000° C. Also, it is advantageous that the melting point of sodium is relatively low (97.8° C.) and the redox reaction of Scheme I is exothermic, which promotes the reaction sequence with minimal investment of external energy.

[0017] Lastly, while sodium is not naturally occurring, its preparation through electrolysis is convenient and it typically does not suffer from the hurdles of direct electrolytic reduction of transition metal oxides, which are provided as ores and are difficult to electrolyze in solution. Moreover, sodium is electrochemically produced from its salt NaCl, which is abundant in nature.

[0018] The second reaction (Reaction II) is the thermal decomposition of the sodium oxide formed in the previous reaction described above. Specifically, this is portrayed in Scheme II:

[0019] Yet another advantage of the present process stems from the net reaction resulting from the combination of the two-reaction sequence. Specifically, the net reaction scheme of Reaction I and Reaction II is shown below as reaction Scheme III (upon balancing the equation through multiplying Scheme II by m):

[0020] As can be immediately appreciated by the person having ordinary skill in the art, the net reaction scheme III does not involve the alkali metal as a substantially consumed reactant, but rather is employed in a regenerative manner / cyclical manner. This is highly advantageous. First, recycling of materials in chemical and commercial large-scale synthesis is very important nowadays, as it is recognized that avoiding material consumption leads to environment preservation. Second, since the alkali metal does not net react, the only by-product of the reaction is oxygen, which is a non-harmful gas and is also easy to separate from the produced transition metal. As found through the process of the resent invention, an intermediate step of separating between the products of the reduction rection, i.e., Na2O and the Fe, greatly improves the ability to dissociate the sodium oxide and complete the regenerative cycle.

[0021] Thus, according to some embodiments, there is provided a process for the reduction of an iron metal oxide, the process comprising:

[0022] (1) providing iron oxide having the formula FenOm, wherein each one of n and m is 1, 2, 3, 4, 5, 6 or 7;

[0023] (2) contacting the iron oxide with sodium metal in a reactor, adjusting the temperature within the reactor to a first temperature in the range of 100° C. to 500° C., to induce a reaction according to scheme I:(3) separating between the Na2O and the Fe;

[0025] (4) elevating the temperature of the separated Na2O to a second temperature, which is at least 50° C. higher than the first temperature, to induce a reaction according to scheme II:so that a net reaction, III, resulting from the reactions of schemes I and II, does not consume the sodium metal:According to some embodiments, the process comprises providing an ore which comprises hematite, magnetite, goethite, nacrite, wustite or a combination thereof. According to some embodiments, the ore further comprises at least one non-iron mineral. According to some embodiments, the non-iron mineral comprise gibbsite, calcite, silicon dioxide, or a combination thereof. Each possibility represents a separate embodiment of the invention. According to some embodiments, the ore further comprises silicon dioxide. According to some embodiments, the iron oxide is selected from the group consisting of: Fe2O3, Fe3O4, FeOOH and combinations thereof. According to some embodiments, the iron oxide comprises Fe2O3.According to some embodiments, the reactor comprises a crucible, wherein step (2) comprises contacting the iron oxide with sodium metal in the crucible. According to some embodiments, the crucible comprises stainless steel, silicon carbide, copper, aluminum nitride, aluminum oxide, Inconel, ZrO2 or a combination thereof. According to some embodiments, the crucible comprises aluminum Nitride, aluminum oxide, copper, Inconel or a combination thereof.

[0028] According to some embodiments, adjusting the temperature within the reactor in step (2) comprises gradually elevating the temperature in the reactor to the first temperature at a rate of 1° C. / minute to 100° C. / minute. According to some embodiments, adjusting the temperature within the reactor in step (2) comprises gradually elevating the temperature in the reactor to the first temperature at a rate of 5° C. / minute to 20° C. / minute.

[0029] According to some embodiments, elevating the temperature to the second temperature in step (4) comprises gradually elevating the temperature in the reactor to the second temperature at a rate of 1° C. / minute to 100° C. / minute. According to some embodiments, elevating the temperature to the second temperature in step (4) comprises gradually elevating the temperature in the reactor to the second temperature at a rate of 5° C. / minute to 20° C. / minute.

[0030] According to some embodiments, the process further comprises step (5) of isolating the sodium metal from the mixture of step (4). According to some embodiments, the isolation of step (5) entails evaporating the sodium metal from the reactor.

[0031] According to some embodiments, the process further comprises step (6) of condensing the evaporated sodium metal; and step (7) of transferring the condensed sodium metal into the reactor, thereby recycling the sodium metal.

[0032] According to some embodiments, the process further comprises:

[0033] (1) providing the iron oxide;

[0034] (2) combining the iron oxide with sodium metal in a reactor, adjusting the temperature within the reactor to the first temperature,

[0035] (3) separating between the Na2O and the Fe;

[0036] (4) elevating the temperature of the separated Na2O to the second temperature to induce a reaction according to scheme III;

[0037] (5) evaporating the sodium metal formed in step (4);

[0038] (6) condensing the evaporated sodium metal; and

[0039] (7) transferring the condensed sodium metal into the reactor;wherein the process further comprises repeating step (1)-(3) for at least one additional sequence.

[0040] According to some embodiments, evaporating the sodium metal is performed at a temperature in the range of 400° C. to 800° C. and at a pressure in the range of 0.001 Bar to 0.5 Bar.

[0041] According to some embodiments, FenOm is Fe2O3, FeO, FeOOH, Fe3O4 or a combination thereof; and reaction schemes I and III are:

[0042] According to some embodiments, step (3) comprises mechanically separating between the Na2O and the Fe to produce an isolated iron metal at a purity of at least 90% w / w.

[0043] According to some embodiments, step (3) comprises magnetically separating between the Na2O and the Fe.

[0044] According to some embodiments, step (4) is performed at a temperature in the range of 400° C. to 800° C.

[0045] According to some embodiments, step (4) is performed at a pressure in the range of 0.001 Bar to 0.5 Bar.

[0046] According to some embodiments, the reaction mixture of step (2) is substantially devoid of additional solvents and carriers, and is consisting essentially of the iron metal oxide, the sodium metal and the products reduced iron metal and sodium oxide.

[0047] According to some embodiments, wherein step (2) is conducted in an air and water protected environment.

[0048] According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio in the range of 1:20 to 20:1.

[0049] According to some embodiments, the reaction mixture of step (4) is substantially devoid of additional solvents and carriers.

[0050] According to some embodiments, step (4) is conducted in an air and water protected environment.

[0051] According to some embodiments, there is provided a process for the reduction of a transition metal oxide, the process comprising:

[0052] (1) providing at least one transition metal oxide having the formula MTnOm, wherein each one of n and m is 1, 2, 3, 4, 5, 6 or 7, wherein MT is a first-row transition metal selected from: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn;

[0053] (2) contacting the at least one transition metal with an alkali metal in a reactor, adjusting the temperature within the reactor to a first temperature which is above the melting point of the alkali metal in the range of 100° C. to 500° C., to induce a reaction according to scheme I:wherein MA is Na or K;(3) separating between the MA2O and the MT;

[0056] (4) elevating the temperature of the separated MA2O to a second temperature, which is at least 50° C. higher than the reduction temperature, to induce a reaction according to scheme II:

[0057] 1.so that a net reaction, III, resulting from the reactions of schemes I and II does not consume the alkali metal:According to some embodiments, step (1) comprises providing an ore which comprises hematite, magnetite, goethite, nacrite, wustite or a combination thereof. According to some embodiments, the ore further comprises at least one non-iron mineral. According to some embodiments, the non-iron mineral comprise gibbsite, calcite, silicon dioxide, or a combination thereof. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal in the crucible. According to some embodiments, adjusting the temperature within the reactor in step (2) comprises gradually elevating the temperature in the reactor to the first temperature at a rate of 1° C. / minute to 100° C. / minute. According to some embodiments, elevating the temperature to the second temperature in step (4) comprises gradually elevating the temperature in the reactor to the second temperature at a rate of 1° C. / minute to 100° C. / minute. According to some embodiments, the process further comprises step (5) of isolating the alkali metal from the mixture of step (4). According to some embodiments, the isolation of step (5) entails evaporating the alkali metal from the reactor. According to some embodiments, the process further comprises step (6) of condensing the evaporated alkali metal; and step (7) of transferring the condensed alkali metal into the reactor, thereby recycling the alkali metal.According to some embodiments, the process comprises:(1) providing the transition metal oxide;

[0061] (2) combining the transition metal oxide with the alkali metal in a reactor, adjusting the temperature within the reactor to the first temperature,

[0062] (3) separating between the MA2O and the MT;

[0063] (4) elevating the temperature of the separated MA2O to the second temperature to induce a reaction according to scheme III;

[0064] (5) evaporating the alkali metal formed in step (4);

[0065] (6) condensing the evaporated alkali metal; and

[0066] (7) transferring the condensed alkali metal into the reactor;

[0067] wherein the process further comprises repeating step (1)-(3) for at least one additional sequence.

[0068] According to some embodiments, evaporating the alkali metal is performed at a temperature in the range of 400° C. to 800° C. and at a pressure in the range of 0.001 Bar to 0.5 Bar.

[0069] According to some embodiments, MT is a first-row transition metal selected from the group consisting of: Fe, Ni, Cr, Cu, Zn and Mn.

[0070] According to some embodiments, MT is Fe; MTnOm is Fe2O3, FeO, FeOOH, Fe3O4 or a combination thereof; and reaction scheme I is:

[0071] According to some embodiments, MT is Ni; MTnOm is NiO; and reaction scheme I is:

[0072] According to some embodiments, MT is Cr; MTnOm is Cr2O3, CrO, CrO3 or a combination thereof; and reaction scheme I is:

[0073] According to some embodiments, MT is Cu; MTnOm is Cu2O, CuO, CuO2, or a combination thereof; and reaction scheme I is:

[0074] According to some embodiments, MT is Zn; MTnOm ZnO; and reaction scheme I is:

[0075] According to some embodiments, MT is Mn; MTnOm is MnO, Mn3O4, Mn2O3, MnO2, Mn2O7 or a combination thereof; and reaction scheme I is:

[0076] According to some embodiments, the process is for the preparation of a metal alloy, wherein

[0077] step (1) comprises providing at least two transition metal oxides having the formulas MTanOm, and MTbiOj, wherein each one of i and j is 1, 2, 3, 4, 5, 6 or 7, wherein each one of MTa, MTb is a transition metal selected from the group consisting of: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn; and

[0078] step (2) comprises combining the transition metal oxides with the alkali metal, wherein reaction scheme I is:and wherein step (2) further induced reaction IV of forming the alloy:According to some embodiments, the alkali metal is sodium and scheme II is:According to some embodiments, step (3) comprises mechanically separating between the MA2O and the MT to produce an isolated MT at a purity of at least 90% w / w. According to some embodiments, step (3) comprises magnetically separating between the MA2O and the MT.According to some embodiments, step (4) is performed at a temperature in the range of 400° C. to 800° C. According to some embodiments, step (4) is performed at a pressure in the range of 0.001 Bar to 0.5 Bar. According to some embodiments, the reaction mixture of step (2) is substantially devoid of additional solvents and carriers, and is consisting essentially of the transition metal oxide, the alkali metal and the products reduced transition metal and alkali metal oxide.

[0083] According to some embodiments, wherein step (2) comprises contacting the transition oxide with alkali metal at a weight ratio in the range of 1:20 to 20:1.

[0084] According to some embodiments, the reaction mixture of step (4) is substantially devoid of additional solvents and carriers.

[0085] According to some embodiments, there is provided a method for reduction of a transition metal oxide, the method comprising:

[0086] contacting a transition metal oxide with an alkali metal to produce a mixture;

[0087] heating the mixture to produce transition metal and alkali metal oxide;

[0088] isolating the transition metal from the heated mixture; and

[0089] thermally decomposing the alkali metal oxide to regenerate the alkali metal.

[0090] According to some embodiments, the method comprises isolating the alkali metal and recycling the alkali metal in another cycle of transition metal oxide reduction.

[0091] According to some embodiments, the isolated transition metal has a purity of at least 90% w / w.

[0092] According to some embodiments, the alkali metal is sodium. According to some embodiments, the alkali metal is potassium.

[0093] According to some embodiments, the transition metal oxide has formula MTnOm wherein:

[0094] each of n and m is independently 1, 2, 3, 4, 5, 6 or 7; and

[0095] MT is selected from Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn.

[0096] According to some embodiments, the transition metal is Fe. According to some embodiments, the transition metal is Ni. According to some embodiments, the transition metal is Cr. According to some embodiments, the transition metal is Cu. According to some embodiments, the transition metal is Zn. According to some embodiments, the transition metal is Mn.

[0097] According to some embodiments, the isolated transition metal is Fe, Co, Ni or Cu and has a purity of at least 99% w / w.

[0098] According to some embodiments, the alkali metal is sodium or potassium; and the transition metal is selected from Fe, Ni, Cr, Cu, Zn and Mn.

[0099] According to some embodiments, the transition metal oxide comprises iron oxide; and the alkali metal is sodium. According to some embodiments, the transition metal oxide is Fe2O3, FeO, Fe3O4, or a combination thereof.

[0100] According to some embodiments, the transition metal oxide comprises copper oxide; and the alkali metal is sodium. According to some embodiments, the transition metal oxide is Cu2O, CuO, CuO2, or a combination thereof.

[0101] According to some embodiments, the transition metal oxide comprises nickel oxide; and the alkali metal is sodium.

[0102] According to some embodiments, the transition metal oxide comprises chromium oxide; and the alkali metal is sodium. According to some embodiments, the transition metal oxide is Cr2O3, CrO, CrO3 or a combination thereof.

[0103] According to some embodiments, the mixture comprises the alkali metal in molar equivalence or excess over the transition metal oxide.

[0104] According to some embodiments, the mixture is neat. According to some embodiments, the heating the mixture comprises heating at a temperature of at least 300° C. According to some embodiments, the heating the mixture comprises heating at a temperature in the range of 300° C. to 3000° C. According to some embodiments, the heating the mixture comprises heating at a temperature of at least 350° C. According to some embodiments, the heating the mixture comprises heating at a temperature of at least 400° C. According to some embodiments, wherein the heating the mixture comprises heating at a temperature of at least 450° C. According to some embodiments, the heating the mixture comprises heating at a temperature of at least 500° C.

[0105] According to some embodiments, the thermally decomposing the alkali metal oxide comprises heating at a temperature equal to or above the decomposition temperature of the alkali metal oxide under reduced pressure.BRIEF DESCRIPTION OF THE FIGURES

[0106] The accompanying figures, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention wherein:

[0107] FIG. 1 is a block diagram representing a process for the reduction of at least one iron oxide into the corresponding iron metal, according to some embodiments.

[0108] FIG. 2 is a block diagram representing a process for the reduction of at least one iron oxide into the corresponding iron metal, according to some embodiments.

[0109] FIG. 3 is a block diagram representing a process for the reduction of at least one transition metal oxide into the corresponding transition metal or alloy thereof, according to some embodiments.

[0110] FIG. 4 is a block diagram representing a process for the reduction of Fe2O3 into iron metal, according to some embodiments.

[0111] FIG. 5 is a block diagram representing a process for the reduction of FeO into iron metal, according to some embodiments.

[0112] FIG. 6 is a block diagram representing a process for the reduction of Fe3O4 into chromium metal, according to some embodiments.

[0113] FIG. 7 is a block diagram representing a process for the reduction of at least one iron oxide into the corresponding iron metal, according to some embodiments.

[0114] FIG. 8 is a block diagram representing a process for the reduction of at least one iron oxide into the corresponding iron metal, according to some embodiments.

[0115] FIG. 9 is a block diagram representing a process for the reduction of at least one transition metal oxide into the corresponding transition metal or alloy thereof, according to some embodiments.

[0116] FIG. 10 is a block diagram representing a process for the reduction of Fe2O3 into iron metal, according to some embodiments.

[0117] FIG. 11 is a block diagram representing a process for the reduction of FeO into iron metal, according to some embodiments.

[0118] FIG. 12 is a block diagram representing a process for the reduction of Fe3O4 into chromium metal, according to some embodiments.

[0119] FIG. 13 is a graph depicting the measured temperature (C) within the reactor vs. time (min) during four reactions between metallic sodium and iron ores ORE1 (dotted line), ORE2 (long dashed), ORE3 (solid line) and ORE4 (dots and dashes).

[0120] FIG. 14 is an XRD pattern of iron produced from the reaction between iron ORE1 and metallic sodium.

[0121] FIG. 15 is an XRD pattern of iron produced from the reaction between iron ORE2 and metallic sodium.

[0122] FIG. 16 is an XRD pattern of iron produced from the reaction between iron ORE3 and metallic sodium.

[0123] FIG. 17 is an XRD pattern of iron produced from the reaction between iron ORE4 and metallic sodium.

[0124] FIG. 18 is a graph depicting the measured temperature (° C.) within the reactor vs. time (min) during the reaction between Fe2O3 and Na to form iron metal, carried out with crucibles made of stainless steel (SS) 304 (blue) and Silicon carbide (dashed line) (solid line), according to some embodiments of the present process.

[0125] FIG. 19 is an XRD pattern of iron produced from the reaction between Fe2O3 and Na, carried out with the SS 304 crucible, according to some embodiments of the present process.

[0126] FIG. 20 is an XRD pattern of iron produced from the reaction between Fe2O3 and Na, carried out with the silicon carbide crucible, according to some embodiments of the present process.

[0127] FIG. 21A is a graph depicting the measured temperature (° C.) within the reactor vs. time (min) during the reaction between iron ore and Na to form iron metal, according to some embodiments of the process.

[0128] FIG. 21B is an X-ray diffraction (XRD) pattern of iron produced from the reaction between iron ore and Na, according to some embodiments of the present process.

[0129] FIG. 22 is an X-ray diffraction (XRD) pattern of iron produced from the reaction between iron ore and Na, according to some embodiments of the present process.

[0130] FIG. 23 is an X-ray diffraction (XRD) pattern of iron produced from the reaction between iron ore and Na, according to some embodiments of the present process.

[0131] FIG. 24 is an X-ray diffraction (XRD) pattern of iron produced from the reaction between iron ore and Na, according to some embodiments of the present process.

[0132] FIG. 25 is an X-ray diffraction (XRD) pattern of iron produced from the reaction between iron ore and Na, according to some embodiments of the present process.

[0133] FIG. 26 is an X-ray diffraction (XRD) pattern of the reaction products of sodium oxide dissociation without prior separation of the sodium oxide from iron, according to some embodiments of the present process.

[0134] FIG. 27 is an X-ray diffraction (XRD) pattern of iron produced from the reaction between iron ore and Na, according to some embodiments of the present process.

[0135] FIG. 28 is an X-ray diffraction (XRD) pattern of sodium oxide separated magnetically from an iron-sodium oxide mixture, according to some embodiments of the present process.

[0136] FIG. 29 schematically shows a system for conducting the process of the present invention.

[0137] FIGS. 30A and 30B are photographs of condensed sodium formed upon the dissociation of sodium oxide.DETAILED DESCRIPTION

[0138] In the following description, various aspects of the disclosure will be described. For the purpose of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the different aspects of the disclosure. However, it will also be apparent to one skilled in the art that the disclosure may be practiced without specific details being presented herein. Furthermore, well-known features may be omitted or simplified in order not to obscure the disclosure.

[0139] Before the present disclosure is described in greater detail, it is to be understood that this disclosure is not limited to particular embodiments described, and as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims.

[0140] According to some embodiments, there is provided a process for the reduction of one or more transition metal oxides into the corresponding transition metals or alloys containing the same. The present process is based on the two-reaction sequence of:wherein n, and m are as described herein, and which results in the net reaction Scheme III:Several advantages of the present process over the art are elaborated herein. In short:(i) The reaction can be done neat (i.e., without solvents), which is environmentally beneficial, according to some embodiments.

[0144] (ii) Conducting Reaction I at a first temperature in the range of 100° C. to 500° C. results in a reaction mixture, wherein the sodium metal is in a reactive liquid state, according to some embodiments.

[0145] (iii) Employment of sodium is advantageous since its melting point is relatively low, so that only moderate energy, or no net energy needs to be invested, according to some embodiments.

[0146] (iv) The redox reaction I is exothermic, which promotes the two-reaction sequence with minimal investment of external energy—another economic and environmental advantage, according to some embodiments.

[0147] (v) The electro-synthesis of sodium, which is recycled during the complete reaction cycle, is convenient, according to some embodiments.

[0148] (vi) The decomposition temperature of sodium oxide is not very high, which further promotes the two-reaction procedure with minimal investment of external energy—yet another economic and environmental advantage, according to some embodiments.

[0149] (vii) the net reaction III, which portrays the combination of reactions I and II does not consume the sodium, i.e., it is fully recycled. Thus only a small amount of the sodium is required to produce large amounts of iron through the present full cycle process, which is also both an economic and environmental advantage.

[0150] (vii) The only by-product of the reaction-sequence of the present invention is oxygen, which is a non-harmful gas and is also easy to separate from the produced transition metal, according to some embodiments.

[0151] According to some embodiments, there is further provided a process for the reduction of one or more transition metal oxides into the corresponding transition metals or alloys containing the same. The present process is based on the reaction sequence of Scheme I:wherein MT, MA, n, and m are as described herein,

[0153] and further isolation of the product reduced transition metal, or alloy thereof, from the reaction mixture. According to some embodiments, the isolating comprises evaporating the alkali metal oxide, and optionally oxygen and / or the alkali metal, from the reactor. According to some embodiments, the evaporation comprises applying reduced pressure to the reaction mixture, applying inert gas flow to the reaction mixture, or both. Each possibility represents a separate embodiment of the invention.

[0154] This enables easy and side-reaction free access to performing the reaction of scheme II, according to some embodiments.which results in the net reaction Scheme III:and total recycling of the alkali metal.As can be appreciated by the person having ordinary skill in the art, several advantages of the present process are as elaborated hereinabove. In addition, the separation of the alkali metal oxide from the reaction mixture (of scheme I) enables easy and clean transformation in Reaction II.

[0158] As can be further appreciated by the person having ordinary skill in the art, the embodiments below may apply to any of the processes disclosed herein.

[0159] According to some embodiments, there is provides a process for the reduction of a transition metal oxide, the process comprising performing steps (1) to (4), and optionally, additional steps, as elaborated herein.

[0160] Specific reference is now made to step (1) of the present process, which comprises providing at least one transition metal oxide, according to some embodiments.

[0161] According to some embodiments, step (1) comprises providing at least one transition metal oxide having the formula MTnOm. According to some embodiments, step (1) comprises providing a transition metal oxide having the formula MTnOm. According to some embodiments, step (1) comprises providing a single transition metal oxide having the formula MTnOm. According to some embodiments, step (1) comprises providing iron oxide having the formula FenOm. According to some embodiments, step (1) comprises providing a single iron oxide having the formula FenOm. According to some embodiments, step (1) comprises providing iron oxide having the formula FenOm, wherein each one of n and m is 1, 2, 3, 4, 5, 6 or 7.

[0162] Specifically, as can be understood by the person having ordinary skill in the art, provision of more than one transition metal oxide of formula MTnOm in step (1) can lead, according to some embodiments, to formation of a transition metal alloy upon completion of the present process, as elaborated herein. Alternatively, according to some embodiments, provision of one transition metal oxide of formula MTnOm in step (1) can lead to the formation of a reduced transition metal upon completion of the present process. Particularly, if the reaction mixture of step (4) contains no metals or metal oxides, which are alloyable with the transition metal provided in step (1), the result of the two-reaction sequence of step (4) will be a transition metal, according to some embodiments. However, if another metal, which is alloyable with the transition metal provided in step (1), or an oxide of such alloyable metal is present in the reaction mixture of step (4), an alloy may form from the two metals.

[0163] According to some embodiments, n is 1, 2, 3, 4, 5, 6 or 7. Each possibility represents a separate embodiment of the invention. According to some embodiments, n is 1, 2 or 3. According to some embodiments, m is 1, 2, 3, 4, 5, 6 or 7. Each possibility represents a separate embodiment of the invention. According to some embodiments, m is 1, 2, 3 or 4.

[0164] According to some embodiments, MT is a metal. According to some embodiments, MT is a transition metal. According to some embodiments, MT is a first-row transition metal.

[0165] Generally, the term “first row transition metal element” refers to any one of the elements 21-29, namely, scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), and copper (Cu).

[0166] According to some embodiments, MT is elected from the group consisting of: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn. Each possibility represents a separate embodiment of the invention. According to some embodiments, MT is a first-row transition metal selected from the group consisting of: Fe, Ni, Cr, Cu, Zn and Mn. According to some embodiments, the transition metal is Sc. According to some embodiments, the transition metal is Ti. According to some embodiments, the transition metal is V. According to some embodiments, the transition metal is Cr. According to some embodiments, the transition metal is Mn. According to some embodiments, the transition metal is Fe. According to some embodiments, the transition metal is Co. According to some embodiments, the transition metal is Ni. According to some embodiments, the transition metal is Cu. According to some embodiments, the transition metal is Zn.

[0167] According to some embodiments, the transition metal oxide is provided in step (1) as a solid.

[0168] As detailed herein, during steps (2) and (4) the transition metal oxide is consumed to provide a transition metal and oxygen, whereas the alkali metal is preserved and recycled, according to some embodiments. This enables to continuously provide additional transition metal oxide into the reaction mixture and to continuously obtain additional transition metal.

[0169] According to some embodiments, during step (2) the alkali metal within the reactor is in molar equivalence or excess over the transition metal oxide therein.

[0170] It is to be understood that “molar excess of X %” and “molar equivalence” as used herein take into account the molar ratios required for a complete reaction according to the scheme presented herein. For example, when the transition metal oxide is Fe2O3, the reaction formula of Scheme I is: Fe2O3+6×Na→3×Na2O+2×Fe, which requires 6 sodium equivalences pers Fe2O3. In such case 6 mols of Na per one mol Fe2O3 is considered molar equivalent and more than 6 mols of Na per one mol Fe2O3 is considered molar excess of sodium, e.g., 12 mols of Na per one mol Fe2O3 is considered 100% mola excess.

[0171] According to some embodiments, during step (2) the alkali metal within the reactor is in molar excess over the transition metal oxide therein. According to some embodiments, the molar excess is at least 10% mol / mol. According to some embodiments, the molar excess is at least 20% mol / mol. According to some embodiments, the molar excess is at least 30% mol / mol. According to some embodiments, the molar excess is at least 40% mol / mol. According to some embodiments, the molar excess is at least 50% mol / mol. According to some embodiments, the molar excess is at least 75% mol / mol. According to some embodiments, the molar excess is at least 100% mol / mol. According to some embodiments, the molar excess is at least 150% mol / mol.

[0172] According to some embodiments, the at least one transition metal oxide is selected from the group consisting of: Sc2O3, TiO2, Ti2O3, VO, V2O3, VO2, V2O5, Cr2O3, CrO, CrO3, MnO, Mn3O4, Mn2O3, MnO2, Mn2O7, Fe2O3, FeO, Fe3O4, CoO, CO2O3, CO3O4, NiO, Cu2O, CuO, CuO2, ZnO and any combination thereof. Each possibility represents a separate embodiment of the invention.

[0173] According to some embodiments, MTnOm comprises Sc2O3.

[0174] According to some embodiments, MTnOm comprises TiO2, Ti2O3 or a combination thereof. According to some embodiments, MTnOm comprises TiO2.

[0175] According to some embodiments, MTnOm comprises Ti2O3. According to some embodiments, MTnOm comprises a mixture of titanium oxides.

[0176] According to some embodiments, MTnOm comprises VO, V2O3, VO2, V2O5 or a combination thereof. According to some embodiments, MTnOm comprises VO.

[0177] According to some embodiments, MTnOm comprises V2O3. According to some embodiments, MTnOm comprises VO2. According to some embodiments, MTnOm comprises V2O5. According to some embodiments, MTnOm comprises a mixture of vanadium oxides.

[0178] According to some embodiments, MTnOm comprises Cr2O3, CrO, CrO3 or a combination thereof. According to some embodiments, MTnOm comprises Cr2O3.

[0179] According to some embodiments, MTnOM comprises CrO. According to some embodiments, MTnOm comprises CrO3. According to some embodiments, MTnOm comprises a mixture of chromium oxides.

[0180] According to some embodiments, MTnOm comprises MnO, Mn3O4, Mn2O3, MnO2, Mn2O7 or a combination thereof. According to some embodiments, MTnOm comprises MnO. According to some embodiments, MTnOm comprises Mn3O4.

[0181] According to some embodiments, MTnOm comprises Mn2O3. According to some embodiments, MTnOm comprises MnO2. According to some embodiments, MTnOm comprises Mn2O7. According to some embodiments, MTnOm comprises a mixture of manganese oxides.

[0182] According to some embodiments, MTnOm comprises Fe2O3, FeOOH, FeO, Fe3O4 or a combination thereof. According to some embodiments, MTnOm comprises Fe2O3. According to some embodiments, MTnOm comprises FeO. According to some embodiments, MTnOm comprises Fe3O4. According to some embodiments, MTnOm comprises FeOOH. According to some embodiments, MTnOm comprises a mixture of iron oxides.

[0183] According to some embodiments, the iron oxide comprises Fe2O3, FeOOH, FeO, Fe3O4 or a combination thereof. According to some embodiments, the iron oxide comprises Fe2O3. According to some embodiments, the iron oxide comprises FeO. According to some embodiments, the iron oxide comprises Fe3O4. According to some embodiments, the iron oxide comprises FeOOH. According to some embodiments, the iron oxide comprises a mixture of iron oxides.

[0184] According to some embodiments, the iron oxide is selected from the group consisting of: Fe2O3, FeOOH, FeO, Fe3O4 and a combination thereof. According to some embodiments, the iron oxide is Fe2O3. According to some embodiments, the iron oxide is FeO. According to some embodiments, the iron oxide is Fe3O4. According to some embodiments, the iron oxide is FeOOH. According to some embodiments, the iron oxide is a mixture of iron oxides.

[0185] According to some embodiments, the iron oxide comprises hematite, magnetite, goethite, nacrite, wustite, or a combination thereof. According to some embodiments, the iron oxide comprises hematite. According to some embodiments, the iron oxide comprises magnetite. According to some embodiments, the iron oxide comprises goethite. According to some embodiments, the iron oxide comprises wustite. According to some embodiments, the iron oxide comprises at least two of hematite, magnetite, wustite and goethite.

[0186] According to some embodiments, step (1) comprises providing an ore, which comprises the transition metal oxide. According to some embodiments, step (1) comprises providing an ore, which comprises the iron oxide.

[0187] According to some embodiments, the ore comprises Fe2O3, FeOOH, FeO, Fe3O4 or a combination thereof. According to some embodiments, the ore comprises Fe2O3. According to some embodiments, the ore comprises FeO. According to some embodiments, the ore comprises Fe3O4. According to some embodiments, the ore comprises FeOOH. According to some embodiments, the ore comprises a mixture of ores.

[0188] According to some embodiments, the ore comprises hematite, magnetite, goethite, nacrite, wustite or a combination thereof. According to some embodiments, the ore comprises hematite. According to some embodiments, the ore comprises magnetite. According to some embodiments, the ore comprises goethite. According to some embodiments, the ore comprises wustite. According to some embodiments, the ore comprises at least two of hematite, wustite, magnetite and goethite.

[0189] According to some embodiments, the ore further comprises at least one of silicon oxide, nacrite, magnesium silicon hydroxide, aluminum hydroxide and a combination thereof. According to some embodiments, the ore further comprises at least two of silicon oxide, nacrite, magnesium silicon hydroxide, aluminum hydroxide and a combination thereof. According to some embodiments, the ore further comprises silicon oxide. According to some embodiments, the ore further comprises nacrite. According to some embodiments, the ore further comprises magnesium silicon hydroxide. According to some embodiments, the ore further comprises aluminum hydroxide.

[0190] According to some embodiments, the ore comprises at least 30% w / w hematite. According to some embodiments, the ore comprises at least 35% w / w hematite. According to some embodiments, the ore comprises at least 40% w / w hematite. According to some embodiments, the ore comprises at least 45% w / w hematite. According to some embodiments, the ore comprises at least 50% w / w hematite. According to some embodiments, the ore comprises at least 55% w / w hematite. According to some embodiments, the ore comprises at least 60% w / w hematite. According to some embodiments, the ore comprises at least 65% w / w hematite. According to some embodiments, the ore comprises no more than 95% w / w hematite. According to some embodiments, the ore comprises no more than 90% w / w hematite. According to some embodiments, the ore comprises no more than 85% w / w hematite. According to some embodiments, the ore comprises 40% to 90% w / w hematite.

[0191] According to some embodiments, the ore comprises at least 1% w / w magnetite. According to some embodiments, the ore comprises at least 2% w / w magnetite. According to some embodiments, the ore comprises at least 3% w / w magnetite. According to some embodiments, the ore comprises at least 5% w / w magnetite. According to some embodiments, the ore comprises at least 10% w / w magnetite. According to some embodiments, the ore comprises at least 12% w / w magnetite. According to some embodiments, the ore comprises no more than 50% w / w magnetite. According to some embodiments, the ore comprises no more than 25% w / w magnetite. According to some embodiments, the ore comprises no more than 20% w / w magnetite. According to some embodiments, the ore comprises 1% to 20% w / w magnetite.

[0192] According to some embodiments, the ore comprises at least 0.3% w / w goethite. According to some embodiments, the ore comprises at least 2% w / w goethite. According to some embodiments, the ore comprises at least 5% w / w goethite. According to some embodiments, the ore comprises at least 10% w / w goethite. According to some embodiments, the ore comprises at least 25% w / w goethite. According to some embodiments, the ore comprises at least 40% w / w goethite. According to some embodiments, the ore comprises no more than 75% w / w goethite. According to some embodiments, the ore comprises no more than 50% w / w goethite. According to some embodiments, the ore comprises 0.3% to 45% w / w goethite.

[0193] According to some embodiments, the ore comprises at least 0.5% w / w nacrite. According to some embodiments, the ore comprises at least 1% w / w nacrite. According to some embodiments, the ore comprises at least 5% w / w nacrite. According to some embodiments, the ore comprises at least 2% w / w nacrite. According to some embodiments, the ore comprises no more than 20% w / w nacrite. According to some embodiments, the ore comprises no more than 15% w / w nacrite. According to some embodiments, the ore comprises 1% to 10% w / w nacrite.

[0194] According to some embodiments, the ore comprises at least 0.5% w / w nacrite. According to some embodiments, the ore comprises at least 1% w / w wustite. According to some embodiments, the ore comprises at least 5% w / w wustite. According to some embodiments, the ore comprises at least 2% w / w wustite. According to some embodiments, the ore comprises no more than 20% w / w wustite. According to some embodiments, the ore comprises no more than 15% w / w wustite. According to some embodiments, the ore comprises 1% to 10% w / w wustite.

[0195] According to some embodiments, the ore further comprises at least one non-iron mineral. According to some embodiments, the non-iron mineral comprise gibbsite, calcite, silicon dioxide, or a combination thereof.

[0196] According to some embodiments, the ore comprises at least 1% w / w silicon dioxide. According to some embodiments, the ore comprises at least 1.5% w / w silicon dioxide. According to some embodiments, the ore comprises at least 2.5% w / w silicon dioxide. According to some embodiments, the ore comprises at least 5% w / w silicon dioxide. According to some embodiments, the ore comprises no more than 20% w / w silicon dioxide. According to some embodiments, the ore comprises no more than 15% w / w silicon dioxide. According to some embodiments, the ore comprises 1% to 15% w / w silicon dioxide.

[0197] According to some embodiments, the ore comprises at least 1% w / w gibbsite. According to some embodiments, the ore comprises at least 1.5% w / w gibbsite. According to some embodiments, the ore comprises at least 2.5% w / w gibbsite. According to some embodiments, the ore comprises at least 5% w / w gibbsite. According to some embodiments, the ore comprises no more than 20% w / w gibbsite. According to some embodiments, the ore comprises no more than 15% w / w gibbsite. According to some embodiments, the ore comprises 1% to 15% w / w gibbsite.

[0198] According to some embodiments, the ore comprises at least 1% w / w calcite. According to some embodiments, the ore comprises at least 1.5% w / w calcite. According to some embodiments, the ore comprises at least 2.5% w / w calcite. According to some embodiments, the ore comprises at least 5% w / w calcite. According to some embodiments, the ore comprises no more than 20% w / w calcite. According to some embodiments, the ore comprises no more than 15% w / w calcite. According to some embodiments, the ore comprises 1% to 15% w / w calcite.

[0199] According to some embodiments, MTnOm comprises Co2O3, CoO, Co3O4 or a combination thereof. According to some embodiments, MTnOm comprises Co2O3. According to some embodiments, MTnOm comprises CoO. According to some embodiments, MTnOm comprises Co3O4. According to some embodiments, MTnOm comprises a mixture of cobalt oxides. According to some embodiments, MTnOm comprises NiO. According to some embodiments, MTnOm comprises Cu2O, CuO, CuO2 or a combination thereof. According to some embodiments, MTnOm comprises Cu2O. According to some embodiments, MTnOm comprises CuO. According to some embodiments, MTnOm comprises CuO2. According to some embodiments, MTnOm comprises a mixture of copper oxides. According to some embodiments, MTnOm comprises ZnO.

[0200] Specific reference is now made to step (2) of the present process, which comprises contacting at least one transition metal with an alkali metal in a reactor. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal in a reactor.

[0201] According to some embodiments, step (2) further comprises adjusting the temperature within the reactor to a first temperature. According to some embodiments, the first temperature is in the range of 100° C. to 500° C. According to some embodiments, step (2) entails inducing a reaction between the iron oxide and the sodium. According to some embodiments, the reaction is according to scheme I:

[0202] According to some embodiments, step (2) entails inducing a reaction between the transition metal oxide and the alkali metal. According to some embodiments, the reaction is according to scheme I:

[0203] According to some embodiments, MA is Na or K.

[0204] According to some embodiments, step (2) comprises combining the transition metal oxide with an alkali metal (MA). According to some embodiments, the action of combining the transition metal oxide with an alkali metal is performed at the first temperature. Specifically, in the case that the reaction has not yet started, external heating is required to reach the first temperature, according to some embodiments. Alternatively, after the reaction has begun, its exothermicity can at least partially maintain or elevate the internal temperature, so that less external heating is required or even the external heating may be at least temporarily ceased, according to some embodiments.

[0205] According to some embodiments, adjusting the temperature within the reactor to a first temperature comprises elevating the temperature within the reactor to the first temperature. According to some embodiments, step (2) comprises adjusting the temperature by induction.

[0206] The term “induction heating” refers to the process of heating electrically conductive materials, namely metals or semi-conductors, by electromagnetic induction, through an induction coil that creates an oscillating electromagnetic field within the coil to heat up and possibly melt steel, copper, brass, graphite, gold, silver, aluminum, or carbide. An induction heater includes an electromagnet and an electronic oscillator that passes an alternating current (AC) through the electromagnet, namely, the antenna. The rapidly alternating magnetic field penetrates the object, generating electric currents inside the conductor called eddy currents. The eddy currents flow through the resistance of the material, and heat it by Joule heating.

[0207] According to some embodiments, the value of the first temperature is selected such that the reactions of scheme I is conducted. In other words, the first temperature brings enough energy to the reaction system to surpass the activation energy of reaction I and provides adequate reaction conditions.

[0208] For the reaction of Scheme I, a key parameter is the physical state of the reactants, according to some embodiments. Specifically, according to some embodiments, it is advantageous that the reactions of the present method are conducted neat (i.e., without any solvents). Also, at room temperature both the alkali metal and the transition metal oxide reactants are in the solid state, which tends to slow-down or prevent chemical reactions.

[0209] According to some embodiments, the first temperature is at least 100° C. According to some embodiments, the first temperature is at least 125° C. According to some embodiments, the first temperature is at least 150° C. According to some embodiments, the first temperature is at least 175° C. According to some embodiments, the first temperature is at least 200° C. According to some embodiments, the first temperature is at least 225° C. According to some embodiments, the first temperature is at least 250° C. According to some embodiments, the first temperature is at least 300° C. According to some embodiments, the first temperature is at least 350° C. According to some embodiments, the first temperature is at least 400° C. According to some embodiments, the first temperature is at least 450° C. According to some embodiments, the first temperature is at least 500° C. According to some embodiments, the first temperature is at least 510° C. According to some embodiments, the first temperature is at least 520° C. According to some embodiments, the first temperature is at least 530° C. According to some embodiments, the first temperature is at least 540° C. According to some embodiments, the first temperature is at least 550° C. According to some embodiments, the first temperature is at least 600. Each possibility represents a separate embodiment of the invention. According to some embodiments, the first temperature is in the range of 200° C. to 300° C. Including each value and sub-range within the specified range.

[0210] According to some embodiments, the first temperature is no more than 600° C. According to some embodiments, the first temperature is no more than 575° C. According to some embodiments, the first temperature is no more than 550° C. According to some embodiments, the first temperature is no more than 500° C. According to some embodiments, the first temperature is no more than 475° C. According to some embodiments, the first temperature is no more than 450° C. According to some embodiments, the first temperature is no more than 425° C. According to some embodiments, the first temperature is no more than 400° C.

[0211] According to some embodiments, the reaction of scheme II takes place wherein sodium oxide is in the solid phase.

[0212] The term “alkali metal” as used herein cover any compound that includes an alkali metal at its 0 (zero) oxidation state. Thus, this term includes sodium metal, Na(0), and potassium metal, K(0), as well as alloys thereof, where at least one alkali metal at its zero oxidation state, e.g., NaK.

[0213] According to some embodiments, the alkali metal (MA) is Na or K. According to some embodiments, the alkali metal is Na. According to some embodiments, the alkali metal is K. According to some embodiments, the alkali metal is NaK.

[0214] Sodium-potassium alloy, colloquially called NaK is an alloy of the alkali metals sodium potassium that is normally liquid at room temperature.

[0215] According to some embodiments, the reaction of Scheme I is conducted neat. According to some embodiments, the reaction of Scheme II is conducted neat. According to some embodiments, the two-reaction sequence of step (2) is conducted neat.

[0216] According to some embodiments, the reaction mixture of step (2) is substantially devoid of additional solvents. According to some embodiments, the reaction mixture of step (2) is substantially devoid of additional solvents and carriers.

[0217] The term “solvent” refers to a non-reactive component of a composition that reduces the viscosity of the composition. Typically, a solvent has a volatility such that it is removed under work-up conditions (such as elevated temperature and / or reduced pressure), after the conclusion of a chemical reaction. The term “substantially devoid solvents” or “solvent-free” refers to a composition that does not contain a solvent, or substantially does not contain a solvent, as defined above. Compositions that substantially do not contain a solvent can contain trace amount, such as ≤5% w / w≤3% w / w, ≤2% w / w. ≤1% or ≤0.5% w / w of solvent according to some embodiments.

[0218] According to some embodiments, the reaction mixture of step (2) is consisting essentially of the transition metal oxide, the alkali metal and the products reduced transition metal or alloy thereof and alkali metal oxide. According to some embodiments, the condensed phase within the reactor during step (2) is consisting essentially of the transition metal oxide, the alkali metal and the products reduced transition metal or alloy thereof and alkali metal oxide

[0219] The term “consisting essentially of” means that the reaction mixture of step (2) includes mainly the transition metal oxide, the alkali metal and the product reduced transition metal or alloy thereof. Specifically, it does not include substantial amounts of solvents or carrier or any constituent that is not involved in reaction Schemes I and II, according to some embodiments. According to some embodiments, the reaction mixture of step (2) includes no more than 5% w / w, no more than 3% w / w, no more than 2% w / w or no more than 1% w / w other compounds. Each possibility represents a separate embodiment of the invention. Other compounds may include impurities from the production or mining of the transition metal oxide.

[0220] According to some embodiments, the resulting reaction mixture formed upon contacting the transition metal oxide and alkali metal in step (2) is in a solid state. According to some embodiments, the resulting reaction mixture formed upon contacting the transition metal oxide and alkali metal in step (2) is a heterogenous mixture.

[0221] According to some embodiments, the reaction mixture of step (2) contains no metals or metal oxides, which are alloyable with the transition metal provided in step (1).

[0222] According to some embodiments, the reaction mixture of step (2) contains alloyable metals or metal oxides, which are alloyable with the transition metal provided in step (1). This is elaborated below when relating to the optional alloy formation.

[0223] According to some embodiments, the alkali metal within the reactor is in molar equivalence excess over the transition metal oxide during step (2). According to some embodiments, the alkali metal within the reactor is in molar excess over the transition metal oxide during step (2). According to some embodiments, the molar excess is at least 5%, least 10%, least 25%, least 50%, least 100% or least 200%. Each possibility represents a separate embodiment of the invention.

[0224] According to some embodiments, the reactor in which step (2) is taking place comprises a crucible. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal in the crucible. According to some embodiments, step (1) is taking place in the crucible. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal in the crucible.

[0225] The term “crucible” refers to a container in which metals or other substances may be melted or subjected to very high temperatures. While crucibles were historically usually made from clay, they can be made from any material that withstands temperatures high enough to melt or otherwise alter its contents.

[0226] According to some embodiments, the crucible has an open-ended cylindrical or conical shape. According to some embodiments, the crucible is thermally resistant. According to some embodiments, the crucible is substantially chemically resistant to reactions with alkali metals. According to some embodiments, the crucible is substantially chemically resistant to reactions with alkali metals at the first temperature.

[0227] According to some embodiments, the crucible comprises stainless steel, silicon carbide, copper, aluminum nitride, alumina, Inconel, ZrO2 or a combination thereof. Each possibility represents a separate embodiment of the invention. According to some embodiments, the crucible comprises aluminum Nitride, aluminum oxide, copper, Inconel or a combination thereof. According to some embodiments, the crucible comprises silicon carbide.

[0228] According to some embodiments, adjusting the temperature within the reactor in step (2) comprises gradually elevating the temperature in the reactor to the first temperature.

[0229] According to some embodiments, adjusting the temperature within the reactor in step (2) comprises gradually elevating the temperature in the reactor to the first temperature.

[0230] According to some embodiments, adjusting the temperature within the reactor in step (2) comprises gradually elevating the temperature in the reactor to the first temperature at a rate of 1° C. / minute to 100° C. / minute. According to some embodiments, adjusting the temperature within the reactor in step (2) comprises gradually elevating the temperature in the reactor to the first temperature at a rate of 5° C. / minute to 20° C. / minute. According to some embodiments, adjusting the temperature within the reactor in step (2) comprises gradually elevating the temperature in the reactor to the first temperature at a rate of 5° C. / minute to 15° C. / minute.

[0231] According to some embodiments, elevating the temperature to the first temperature is performed at a rate of at least 1° C. / minute. According to some embodiments, elevating the temperature to the first temperature is performed at a rate of at least 2° C. / minute. According to some embodiments, elevating the temperature to the first temperature is performed at a rate of at least 5° C. / minute. According to some embodiments, elevating the temperature to the first temperature is performed at a rate of at least 7° C. / minute. According to some embodiments, elevating the temperature to the first temperature is performed at a rate of at least 10° C. / minute. According to some embodiments, elevating the temperature to the first temperature is performed at a rate of at least 15° C. / minute. According to some embodiments, the rate is no more than 100° C. / minute. According to some embodiments, the rate is no more than 75° C. / minute. According to some embodiments, the rate is no more than 50° C. / minute. According to some embodiments, the rate is no more than 40° C. / minute. According to some embodiments, the rate is no more than 30° C. / minute. According to some embodiments, the rate is no more than 20° C. / minute. According to some embodiments, the rate is no more than 15° C. / minute. According to some embodiments, the rate is in the range of 1° C. / minute to 100° C. / minute. According to some embodiments, the rate is in the range of 5° C. / minute to 20° C. / minute.

[0232] According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio in the range of 1:20 to 20:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio in the range of 1:10 to 10:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio in the range of 1:5 to 5:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio in the range of 1:3 to 3:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio in the range of 1:2 to 2:1.

[0233] According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of at least 1:10. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of at least 1:8. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of at least 1:7. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of at least 1:5. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of at least 1:4. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of at least 1:3. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of at least 1:2. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of at least 1:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of at least 1.5:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of no more than 10:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of no more than 7:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of no more than 5:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of no more than 4:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of no more than 3:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of no more than 2:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of no more than 1:1. According to some embodiments, step (2) comprises contacting the transition metal oxide with alkali metal at a weight ratio of no more than 1:1.5. It is to be understood that in the context of the present paragraph, “at least” and “no more than” refer to the number in the numerator. For example, at least 1:10 may include, but is not limited to, 1:10, 3:10, 7:10, 17:10 etc.; and no more than 5:1 may include, but is not limited to, 5:1, 4:1, 1:1, 0.7:1 etc.

[0234] According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of at least 1:10. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of at least 1:8. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of at least 1:7. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of at least 1:5. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of at least 1:4. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of at least 1:3. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of at least 1:2. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of at least 1:1. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of at least 1.5:1. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of no more than 10:1. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of no more than 7:1. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of no more than 5:1. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of no more than 4:1. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of no more than 3:1. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of no more than 2:1. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of no more than 1:1. According to some embodiments, step (2) comprises contacting the iron oxide with sodium metal at a weight ratio of no more than 1:1.5.

[0235] According to some embodiments, step (2) is conducted in an air-protected environment. According to some embodiments, step (2) is conducted in a water-protected environment. According to some embodiments, step (2) is conducted in an air and water protected environment.

[0236] Specifically, it is to be understood that alkali metals are highly reactive and require specific reaction conditions, such as performance under inert gas.

[0237] According to some embodiments, step (2) further comprises flowing inert gas into the reactor. According to some embodiments, step (2) is performed under inert gas. According to some embodiments, the inert gas in nitrogen or argon. Each possibility represents a separate embodiment of the invention.

[0238] According to some embodiments, during step (2) the reactor is closed. According to some embodiments, during step (2) the reactor is closed under an inert atmosphere. According to some embodiments, during step (2) the reactor is closed under an inert gas atmosphere. According to some embodiments, during step (2) the reactor is closed and the two-reaction sequence is performed at an elevated pressure.

[0239] The term “elevated pressure” refers to any pressure above atmospheric pressure.

[0240] Advantageously, the reaction duration is short, which is both economical and energy-consuming.

[0241] According to some embodiments, step (2) is performed for no more than 6 hours, no more than 4 hours, no more than 3 hours, no more than 2 hours, no more than 1 hour, no more than 45 minutes, or no more than 30 minutes. Each possibility represents a separate embodiment of the invention. According to some embodiments, step (2) is performed for no more than 1 hour. According to some embodiments, step (2) is performed for at least 5 minutes, at least 10 minutes, at least 15 minutes, at least 20 minutes or at least 25 minutes. Each possibility represents a separate embodiment of the invention.

[0242] It is to be understood that reference to the duration of step (2) refers to an individual run of step (2). Specifically, as detailed herein, according to some embodiments, the present process is performed cyclically, with the alkali metal recycled after the completion of the reaction, back to be re-used in a subsequent run of step (2). thus, it is to be understood that repeats of step (2) are allowed to cumulatively surpass the bottom threshold set above, without contradicting the above clause, which is directed to the individual run of step (2).

[0243] According to some embodiments, step (2) further comprises providing iron powder and contacting the iron oxide with sodium metal in the reactor in the presence of the iron powder. Specifically, addition of iron powder was found to improve the efficiency of Reaction I. According to some embodiments, step (2) further comprises providing transition metal powder and contacting the transition metal oxide with the alkali metal in the reactor in the presence of the powder.

[0244] Specific reference is now made to step (3) of the present process, which comprises separating between the MA2O and the MT. According to some embodiments, step (3) comprises separating between the Na2O and the Fe.

[0245] According to some embodiments, step (3) comprises isolating the reduced transition metal or alloy thereof, from the reaction mixture. According to some embodiments, step (3) comprises isolating the reduced transition metal from the reaction mixture. According to some embodiments, step (3) comprises isolating the reduced transition metal alloy from the reaction mixture. According to some embodiments, step (3) comprises isolating the reduced iron from the reaction mixture.

[0246] According to some embodiments, the isolation of step (3) further comprises collecting the isolated transition metal or alloy thereof. According to some embodiments, the isolation of step (3) further comprises collecting the isolated iron metal or alloy thereof.

[0247] According to some embodiments, the isolated reduced transition metal or alloy thereof is in a condensed phase. According to some embodiments, the isolated reduced transition metal or alloy thereof is isolated as a solid. According to some embodiments, the isolated reduced transition metal or alloy thereof is isolated as a liquid. According to some embodiments, the iron is a condensed phase. According to some embodiments, the isolated reduced iron is isolated as a solid. According to some embodiments, the isolated iron is isolated as a liquid.

[0248] According to some embodiments, step (3) comprises isolating the alkali metal oxide from the reaction mixture. According to some embodiments, step (3) comprises isolating the sodium oxide from the reaction mixture.

[0249] According to some embodiments, the isolation of step (3) further comprises collecting the isolated alkali metal oxide. According to some embodiments, the isolation of step (3) further comprises collecting the isolated sodium oxide.

[0250] According to some embodiments, step (3) comprises separating between the MA2O and the MT to produce an isolated transition metal at a purity of at least 90% w / w. According to some embodiments, step (3) comprises separating between the MA2O and the MT to produce an isolated transition metal at a purity of at least 95% w / w. According to some embodiments, step (3) comprises separating between the Na2O and the Fe to produce an isolated iron metal at a purity of at least 90% w / w. According to some embodiments, step (3) comprises separating between the Na2O and the Fe to produce an isolated iron metal at a purity of at least 95% w / w.

[0251] According to some embodiments, step (3) comprises separating between the MA2O and the MT to produce an isolated alkali metal at a purity of at least 80% w / w. According to some embodiments, step (3) comprises separating between the MA2O and the MT to produce an isolated alkali metal at a purity of at least 90% w / w. According to some embodiments, step (3) comprises separating between the MA2O and the MT to produce an isolated alkali metal at a purity of at least 95% w / w. According to some embodiments, step (3) comprises separating between the Na2O and the Fe to produce an isolated sodium metal at a purity of at least 80% w / w. According to some embodiments, step (3) comprises separating between the Na2O and the Fe to produce an isolated sodium metal at a purity of at least 90% w / w. According to some embodiments, step (3) comprises separating between the Na2O and the Fe to produce an isolated sodium metal at a purity of at least 95% w / w.

[0252] According to some embodiments, step (3) comprises mechanically separating between the MA2O and the MT. According to some embodiments, step (3) comprises mechanically separating between the Na2O and the Fe.

[0253] According to some embodiments, step (3) comprises magnetically separating between the MA2O and the MT. According to some embodiments, step (3) comprises magnetically separating between the Na2O and the Fe.

[0254] Also, in industrial processes, the transition metal oxides may be provided from ores, which contain contaminants, such as silicon oxides (typically, silicon dioxide). When providing such transition metal oxide compositions in step (1) of the present process, they may not react and the contaminants may be separated using an additional step of melting the transition metal product and filtering / skimming off the contaminants.

[0255] Specific reference is now made to step (4) of the present process, which comprises elevating the temperature of the separated MA2O to a second temperature. According to some embodiments, step (4) of the present process, comprises elevating the temperature of the separated Na2O to a second temperature According to some embodiments, the second temperature at least 50° C. higher than the first temperature.

[0256] According to some embodiments, step (4) entails inducing a reaction according to scheme II:

[0257] 2.

[0258] According to some embodiments, a net reaction, III, resulting from the reactions of schemes I and II, does not consume the alkali metal:

[0259] According to some embodiments, step (4) entails inducing a reaction according to scheme II:

[0260] According to some embodiments, a net reaction, III, resulting from the reactions of schemes I and II, does not consume the sodium metal:

[0261] According to some embodiments, the combination of reaction schemes I and II (multiplied by m) results in a net reaction, represented by reaction Scheme III:

[0262] It is to be understood that in order to balance and subtract the equations of Schemes I and II, the equation of Scheme II needs to be multiplied by m (the number of oxygen atoms in the transition metal oxide compound).

[0263] For clarity the corresponding iron reaction sequence schemes are provided below:

[0264] For the reaction of Scheme II, a key parameter is the activation energy required to decompose the alkali metal oxide, according to some embodiments. Therefore, according to some embodiments, the second temperature is equal or above the decomposition temperature of MA2O under that reactor-specific conditions. According to some embodiments, the second temperature is above the decomposition temperature of MA2O.

[0265] According to some embodiments, upon decomposition of the sodium oxide, the resulting products, sodium and oxygen are initially in the gas phase.

[0266] According to some embodiments, net reaction, III, resulting from said Reaction I and Reaction II does not consume the alkali metal. According to some embodiments, the alkali metal is used and recycled in the two-reaction sequence of steps (2) and (4). According to some embodiments, the alkali metal is recycled in the two-reaction sequence of steps (2) and (4).

[0267] It is to be understood that while the net reaction III does not consume the alkali metal, some of the alkali metal may be gradually consumed during step (2). Specifically, side reactions which may take place when the transition metal oxide is impure or of lower grade, may gradually consume at least some of the alkali metal. Yet, the specific net reaction III does not consume the alkali metal. Also, it was found that the separation of step (III) reduces the consumption of alkali metal (e.g., sodium).

[0268] According to some embodiments, the resulting reaction mixture conducting step (4) is in a fluid state. According to some embodiments, the resulting reaction mixture conducting step (4) is in a liquid state.

[0269] According to some embodiments, the reaction mixture formed upon conducting step (4) comprises the reduced transition metal, MT, or alloy thereof. According to some embodiments, the reaction mixture formed upon conducting step (4) further comprises oxygen. According to some embodiments, oxygen gas is separated from the reaction mixture.

[0270] According to some embodiments, step (4) is taking place in the same reactor in which step (2) is taking place. According to some embodiments, steps (2) and (4) are taking place in different parts of the same reactor. According to some embodiments, steps (2) and (4) are taking place in different chambers of the same reactor. According to some embodiments, adjusting the temperature within the reactor in step (4) comprises gradually elevating the temperature in the reactor to the second temperature.

[0271] According to some embodiments, adjusting the temperature within the reactor in step (4) comprises gradually elevating the temperature in the reactor to the second temperature at a rate of 1° C. / minute to 100° C. / minute. According to some embodiments, adjusting the temperature within the reactor in step (4) comprises gradually elevating the temperature in the reactor to the second temperature at a rate of 5° C. / minute to 20° C. / minute.

[0272] According to some embodiments, elevating the temperature to the second temperature is performed at a rate of at least 1° C. / minute. According to some embodiments, elevating the temperature to the second temperature is performed at a rate of at least 2° C. / minute. According to some embodiments, elevating the temperature to the second temperature is performed at a rate of at least 5° C. / minute. According to some embodiments, elevating the temperature to the second temperature is performed at a rate of at least 7° C. / minute. According to some embodiments, elevating the temperature to the second temperature is performed at a rate of at least 10° C. / minute. According to some embodiments, elevating the temperature to the second temperature is performed at a rate of at least 15° C. / minute. According to some embodiments, the rate is no more than 100° C. / minute. According to some embodiments, the rate is no more than 75° C. / minute. According to some embodiments, the rate is no more than 50° C. / minute. According to some embodiments, the rate is no more than 40° C. / minute. According to some embodiments, the rate is no more than 30° C. / minute. According to some embodiments, the rate is no more than 20° C. / minute. According to some embodiments, the rate is no more than 15° C. / minute. According to some embodiments, the rate is in the range of 1° C. / minute to 100° C. / minute. According

[0273] According to some embodiments, step (4) is conducted in an air-protected environment. According to some embodiments, step (4) is conducted in a water-protected environment. According to some embodiments, step (4) is conducted in an air and water protected environment.

[0274] Specifically, it is to be understood that alkali metals are highly reactive and require specific reaction conditions, such as performance under inert gas.

[0275] According to some embodiments, step (4) further comprises flowing inert gas into the reactor. According to some embodiments, step (4) is performed under inert gas. According to some embodiments, the inert gas in nitrogen or argon. Each possibility represents a separate embodiment of the invention.

[0276] According to some embodiments, during step (4) the reactor is closed. According to some embodiments, during step (4) the reactor is closed under an inert atmosphere. According to some embodiments, during step (4) the reactor is closed under an inert gas atmosphere. According to some embodiments, during step (4) the reactor is closed and the two-reaction sequence is performed at an elevated pressure.

[0277] Advantageously, the reaction duration is short, which is both economical and energy-consuming.

[0278] According to some embodiments, step (4) is performed for no more than 6 hours, no more than 4 hours, no more than 3 hours, no more than 2 hours, no more than 1 hour, no more than 45 minutes, or no more than 30 minutes. Each possibility represents a separate embodiment of the invention. According to some embodiments, step (4) is performed for no more than 1 hour. According to some embodiments, step (4) is performed for at least 5 minutes, at least 10 minutes, at least 15 minutes, at least 20 minutes or at least 25 minutes. Each possibility represents a separate embodiment of the invention.

[0279] According to some embodiments, FenOm is Fe2O3, FeO, FeOOH, Fe3O4 or a combination thereof; and reaction schemes I and III are:

[0280] According to some embodiments, MT is Fe; MTnOm is Fe2O3, FeO, FeOOH, Fe3O4 or a combination thereof; and reaction scheme I is:

[0281] According to some embodiments, MT is Ni; MTnOm is NiO; and reaction scheme I is:

[0282] According to some embodiments, MT is Cr; MTnOm is Cr2O3, CrO, CrO3 or a combination thereof; and reaction scheme I is:

[0283] According to some embodiments, MT is Cu; MTnOm is Cu2O, CuO, CuO2, or a combination thereof; and reaction scheme I is:

[0284] According to some embodiments, MT is Zn; MTnOm ZnO; and reaction scheme I is:

[0285] According to some embodiments, MT is Mn; MTnOm is MnO, Mn3O4, Mn2O3, MnO2, Mn2O7 or a combination thereof; and reaction scheme I is:

[0286] According to some embodiments, the second temperature at least 50° C. higher than the first temperature. According to some embodiments, the second temperature at least 60° C. higher than the first temperature. According to some embodiments, the second temperature at least 70° C. higher than the first temperature. According to some embodiments, the second temperature at least 80° C. higher than the first temperature. According to some embodiments, the second temperature at least 90° C. higher than the first temperature. According to some embodiments, the second temperature at least 100° C. higher than the first temperature. According to some embodiments, the second temperature at least 120° C. higher than the first temperature. According to some embodiments, the second temperature at least 140° C. higher than the first temperature. According to some embodiments, the second temperature at least 150° C. higher than the first temperature.

[0287] According to some embodiments, the second temperature 50 to 150° C. higher than the first temperature, including each value and sub-range within the specified range.

[0288] According to some embodiments, step (4) is performed at a temperature in the range of 400° C. to 800° C. According to some embodiments, step (4) is performed at a temperature in the range of 700° C. to 800° C. According to some embodiments, the second temperature is in the range of 700° C. to 800° C.

[0289] According to some embodiments, step (4) is performed at a temperature of at least 300° C. According to some embodiments, step (4) is performed at a temperature of at least 350° C. According to some embodiments, step (4) is performed at a temperature of at least 400° C. According to some embodiments, step (4) is performed at a temperature of at least 450° C. According to some embodiments, step (4) is performed at a temperature of at least 500° C. According to some embodiments, step (4) is performed at a temperature of at least 550° C. According to some embodiments, step (4) is performed at a temperature of at least 600° C. According to some embodiments, step (4) is performed at a temperature of at least 650° C. According to some embodiments, step (4) is performed at a temperature of at least 700° C. According to some embodiments, step (4) is performed at a temperature of at least 750° C. According to some embodiments, step (4) is performed at a temperature of no more than 1000° C. According to some embodiments, step (4) is performed at a temperature of no more than 900° C. According to some embodiments, step (4) is performed at a temperature of no more than 800° C. According to some embodiments, step (4) is performed at a temperature of no more than 700° C. According to some embodiments, step (4) is performed at a temperature of no more than 600° C.

[0290] According to some embodiments, step (4) is performed at a pressure in the range of 0.001 Bar to 0.5 Bar, including each value and sub-range within the specified range.

[0291] According to some embodiments, step (4) is performed at a pressure of no more than 0.5 Bar. According to some embodiments, step (4) is performed at a pressure of no more than 0.25 Bar. According to some embodiments, step (4) is performed at a pressure of no more than 0.1 Bar. According to some embodiments, step (4) is performed at a pressure of no more than 0.05 Bar. According to some embodiments, step (4) is performed at a pressure of no more than 0.01 Bar. According to some embodiments, step (4) is performed at a pressure of no more than 0.005 Bar.

[0292] According to some embodiments, the reaction mixture of step (4) is substantially devoid of additional solvents and carriers. According to some embodiments, step (4) is conducted in an air and water protected environment.

[0293] According to some embodiments, the present process further comprises step (5). Specific reference is now made to step (5) of the present process, which comprises isolating the alkali metal from the mixture of step (4). According to some embodiments, step (5) comprises isolating the sodium metal from the mixture of step (4).

[0294] According to some embodiments, step (5) comprises isolating the alkali metal from the reaction mixture. According to some embodiments, step (5) comprises isolating the sodium from the reaction mixture.

[0295] According to some embodiments, the isolation of step (5) further comprises collecting the isolated alkali metal. According to some embodiments, the isolation of step (5) further comprises collecting the isolated sodium. According to some embodiments, the isolation of step (5) further comprises storing the isolated sodium.

[0296] According to some embodiments, the isolation of step (5) entails evaporating the alkali metal from the reactor. According to some embodiments, the isolation of step (5) entails evaporating the sodium metal from the reactor.

[0297] According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 200° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 250° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 300° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 350° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 400° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 450° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 500° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 550° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 575° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 600° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 650° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 700° C. According to some embodiments, evaporating the alkali metal is performed at a temperature of at least 570° C. According to some embodiments, evaporating the alkali metal is performed at a temperature no more than 1000° C. According to some embodiments, evaporating the alkali metal is performed at a temperature no more than 900° C. According to some embodiments, evaporating the alkali metal is performed at a temperature no more than 800° C. According to some embodiments, evaporating the alkali metal is performed at a temperature no more than 700° C. According to some embodiments, evaporating the alkali metal is performed at a temperature in the range of 200° C. to 1000° C., including each value and sub-range within the specified range. According to some embodiments, evaporating the alkali metal is performed at a temperature in the range of 300° C. to 900° C. According to some embodiments, evaporating the alkali metal is performed at a temperature in the range of 400° C. to 800° C. According to some embodiments, evaporating the alkali metal is performed at a temperature in the range of 500° C. to 700° C. According to some embodiments, evaporating the alkali metal is performed at a temperature in the range of 550° C. to 650° C.

[0298] According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 200° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 250° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 300° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 350° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 400° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 450° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 500° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 550° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 575° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 600° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 650° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 700° C. According to some embodiments, evaporating the sodium metal is performed at a temperature of at least 570° C. According to some embodiments, evaporating the sodium metal is performed at a temperature no more than 1000° C. According to some embodiments, evaporating the sodium metal is performed at a temperature no more than 900° C. According to some embodiments, evaporating the sodium metal is performed at a temperature no more than 800° C. According to some embodiments, evaporating the sodium metal is performed at a temperature no more than 700° C. According to some embodiments, evaporating the sodium metal is performed at a temperature in the range of 200° C. to 1000° C., including each value and sub-range within the specified range. According to some embodiments, evaporating the sodium metal is performed at a temperature in the range of 300° C. to 900° C. According to some embodiments, evaporating the sodium metal is performed at a temperature in the range of 400° C. to 800° C. According to some embodiments, evaporating the sodium metal is performed at a temperature in the range of 500° C. to 700° C. According to some embodiments, evaporating the sodium metal is performed at a temperature in the range of 550° C. to 650° C.

[0299] According to some embodiments, evaporating the alkali metal is performed at a reduced pressure. According to some embodiments, evaporating the alkali metal is performed at a pressure in the range of 0.001 Bar to 0.2 Bar. According to some embodiments, evaporating the alkali metal is performed at a pressure in the range of 0.001 Bar to 0.5 Bar, including each value and sub-range within the specified range. According to some embodiments, evaporating the sodium metal is performed at a reduced pressure. According to some embodiments, evaporating the sodium metal is performed at a pressure in the range of 0.001 Bar to 0.2 Bar. According to some embodiments, evaporating the sodium metal is performed at a pressure in the range of 0.001 Bar to 0.5 Bar, including each value and sub-range within the specified range.

[0300] According to some embodiments, the evaporating is performed for at least 10 minutes, at least 20 minutes, at least 30 minutes, at least 45 minutes, at least 60 minutes or at least 90 minutes. According to some embodiments, the evaporating is performed for about 2 hours.

[0301] According to some embodiments, the evaporating of step (5) comprises applying reduced pressure to the reaction mixture. According to some embodiments, the isolation of step (5) entails evaporating the sodium metal produced in reaction scheme II and transferring the sodium metal out of the reactor. According to some embodiments, the evaporation involves heating the sodium metal. According to some embodiments, the evaporation involves reducing the pressure within the reactor. According to some embodiments, the isolation of step (5) entails evaporating the sodium metal from the reactor. According to some embodiments, the isolation of step (5) entails boiling the sodium metal from the reactor.

[0302] According to some embodiments, the evaporating of step (5) comprises inert gas flow to the reaction mixture.

[0303] Specific reference is now made to step (6) of the present process.

[0304] According to some embodiments, the process further comprises step (6) of condensing the evaporated alkali metal. According to some embodiments, the process further comprises step (6) of condensing the evaporated sodium metal.

[0305] According to some embodiments, the evaporated alkali metal is condensed in a dedicated container in step (6). According to some embodiments, the evaporated sodium metal is condensed in a dedicated container in step (6). According to some embodiments, the container is kept at air- and / or water-protected conditions. According to some embodiments, the container is a sealable container.

[0306] In general, alkali metals are solid materials at room temperature and atmospheric pressure. In step (5) the alkali metal is heated, and optionally put in reduced pressure, so that it transforms into vapor, according to some embodiments. Step (6) is relevant when the isolation of step (5) comprises such vaporization, and it comprises the condensation of the alkali metal vapor in a separate container, according to some embodiments. Although the term “condense” typically refers to the transformation from gas to liquid, it is to be understood that the condensed alkali metals may gradually or instantaneously transform into solids, depending, e.g., on the temperature in the alkali metal container. Thus, the term “condense” in the context of step (6) further comprises deposition of gas to solid.

[0307] According to some embodiments, the condensation of step (6) is performed at a temperature which is lower than the second temperature. According to some embodiments, the condensation of step (6) is performed at a temperature which is at least 100° C. lower than the second temperature. According to some embodiments, the condensation of step (6) is performed at a temperature which is at least 200° C. lower than the second temperature. According to some embodiments, the condensation of step (6) is performed at a temperature which is at least 250° C. lower than the second temperature. According to some embodiments, the condensation of step (6) is performed at a temperature which is at least 300° C. lower than the second temperature. According to some embodiments, the condensation of step (6) is performed at a temperature which is at least 350° C. lower than the second temperature. According to some embodiments, the condensation of step (6) is performed at a temperature which is at least 400° C. lower than the second temperature.

[0308] According to some embodiments, the pressure within the condensation container is substantially equal to the pressure within the reaction during the evaporation and / or condensation steps. In this context, “substantially equal pressure” refers to a range of ±25%, ±20%, ±15%, ±10%, ±5%, ±0.1 Bar, ±0.05 Bar, ±0.1 Bar or ±0.001 Bar. Each possibility represents a separate embodiment of the invention.

[0309] Specific reference is now made to step (7) of the present process.

[0310] According to some embodiments, the process further comprises step (7) of transferring the condensed alkali metal into the reactor, thereby recycling the alkali metal. According to some embodiments, the process further comprises step (7) of transferring the condensed sodium metal into the reactor, thereby recycling the sodium metal.

[0311] According to some embodiments, the alkali metal is transferred to the reactor in step (7) as a condensed material. According to some embodiments, the alkali metal is transferred to the reactor in step (7) as a liquid. According to some embodiments, the alkali metal is transferred to the reactor in step (7) as a solid.

[0312] It is to be understood that by performing step (7), one cycle of the present process is complete. Upon the reconstitution of alkali metal and additional provision of transition metal oxide, the process may continue to an additional cycle, according to some embodiments.

[0313] According to some embodiments, the process further comprises repeating steps (1)-(3) for at least one additional sequence after step (7). According to some embodiments, the process further comprises repeating steps (1)-(4) for at least one additional sequence after step (7). According to some embodiments, the process further comprises repeating steps (1)-(3) for at least one additional sequence.

[0314] According to some embodiments, the process comprises: performing steps (1)-(4) for at least one cycle and performing steps (1)-(4). According to some embodiments, the process comprises: performing steps (1)-(4) for a plurality of cycles. According to some embodiments, the process comprises: performing steps (1)-(5) for a plurality of cycles. According to some embodiments, the process comprises: performing steps (1)-(6) for a plurality of cycles. According to some embodiments, the process comprises: performing steps (1)-(7) for a plurality of cycles.

[0315] The term “plurality” refers to any integer higher than 1.

[0316] According to some embodiments, the process comprises:

[0317] (1) providing the transition metal oxide;

[0318] (2) combining the transition metal oxide with the alkali metal in a reactor, adjusting the temperature within the reactor to the first temperature,

[0319] (3) separating between the MA2O and the MT;

[0320] (4) elevating the temperature of the separated MA2O to the second temperature to induce a reaction according to scheme III;

[0321] (5) evaporating the alkali metal formed in step (4);

[0322] (6) condensing the evaporated alkali metal; and

[0323] (7) transferring the condensed alkali metal into the reactor;

[0324] wherein the process further comprises repeating step (1)-(3) for at least one additional sequence.

[0325] According to some embodiments, the process further comprises:

[0326] (1) providing the iron oxide;

[0327] (2) combining the iron oxide with sodium metal in a reactor, adjusting the temperature within the reactor to the first temperature,

[0328] (3) separating between the Na2O and the Fe;

[0329] (4) elevating the temperature of the separated Na2O to the second temperature to induce a reaction according to scheme III;

[0330] (5) evaporating the sodium metal formed in step (4);

[0331] (6) condensing the evaporated sodium metal; and

[0332] (7) transferring the condensed sodium metal into the reactor;wherein the process further comprises repeating step (1)-(3) for at least one additional sequence.

[0333] Reference is now made to FIGS. 1-2, which are block diagrams representing a process for the reduction of at least one transition metal oxide into the corresponding transition metal or alloy thereof.

[0334] Specifically, FIG. 17 is a block diagram representing a process for the reduction of at least one iron oxide into the corresponding iron, which comprises steps (1), (2), (3) and (4) as detailed herein, according to some embodiments. Step (1) is represented by block 2000, step (2) is represented by block 2010 and step (3) is represented by block 2020 and step (3) is represented by block 2021.

[0335] Similarly, FIG. 8 is a block diagram representing a process for the reduction of at least one iron oxide into the corresponding iron, which comprises steps (1), (2), (3), (4), (5), (6) and (7) as detailed herein, according to some embodiments. Step (1) is represented by block 2000, step (2) is represented by block 2010, step (3) is represented by blocks 2020 and 2030, step (4) is represented by block 2021, step (5) is represented by block 2035, step (6) is represented by block 2040 and step (7) is represented by block 2050.

[0336] Similarly, FIG. 3 is a block diagram representing a process for the reduction of at least one transition metal oxide into the corresponding transition metal, which comprises steps (1), (2), (3), (4), (5), (6) and (7) as detailed herein, according to some embodiments. Step (1) is represented by block 2000, step (2) is represented by block 2010, step (3) is represented by blocks 2020 and 2030, step (4) is represented by block 2021, step (5) is represented by block 2035, step (6) is represented by block 2040 and step (7) is represented by block 2050.

[0337] Below are provided non-limiting specific embodiments of specific reaction sequences, which can be conducted by the processes of the present invention. Reference in further made to FIGS. 4-6, which are block diagrams, each representing a selected process for the reduction of at least one transition metal oxide into the corresponding transition metal or alloy thereof (i.e., a specific two-reaction sequence). Each one of FIGS. 4-6 represent a process comprising steps (1), (2), (3) and (4) as detailed herein, according to some embodiments, step (1) is represented by block 2000, step (2) is represented by block 2010, step (3) is represented by block 2020 and step (4) is represented by block 2021.

[0338] According to some embodiments, the alkali metal is Na and scheme II is:

[0339] FIGS. 4-6 and 10-12 refer to reaction sequences, which employ sodium as the alkali metal.

[0340] According to some embodiments, the alkali metal is K and scheme TT is:

[0341] According to some embodiments, MT is Fe; MTnOm is Fe2O3 (the iron oxide is Fe2O3) MA is Na and reaction schemes I and III are:

[0342] This transformation is portrayed in FIGS. 4 and 10.

[0343] Also, reaction Scheme II for MA=Na is provided above and can be appreciated by the person having ordinary skill in the art in each of the reaction sequences below.

[0344] According to some embodiments, MT is Fe; MTnOm is Fe2O3 (the iron oxide is Fe2O3), MA is K and reaction schemes I and III are:

[0345] Also, reaction Scheme II for MA=K is provided above and can be appreciated by the person having ordinary skill in the art in each of the reaction sequences below.

[0346] According to some embodiments, MT is Fe; MTnOm is FeO (the iron oxide is FeO), MA is Na and reaction schemes I and III are:

[0347] This transformation is portrayed in FIGS. 5 and 11.

[0348] According to some embodiments, MT is Fe; MTnOm is FeO, (the iron oxide is FeO) MA is K and reaction schemes I and III are:

[0349] According to some embodiments, MT is Fe; MTnOm is Fe3O4 (the iron oxide is Fe3O4), MA is Na and reaction schemes I and III are:

[0350] This transformation is portrayed in FIGS. 6 and 12.

[0351] According to some embodiments, MT is Fe; MTnOm is Fe3O4, MA is K and reaction schemes I and III are:

[0352] According to some embodiments, MT is Ni; MTnOm is NiO, MA is Na and reaction schemes I and III are:

[0353] According to some embodiments, MT is Ni; MTnOm is NiO, MA is K and reaction schemes I and III are:

[0354] According to some embodiments, MT is Cr; MTnOm is Cr2O3, MA is Na and reaction schemes I and III are:

[0355] According to some embodiments, MT is Cr; MTnOm is Cr2O3, MA is K and reaction schemes I and III are:

[0356] According to some embodiments, MT is Cr; MTnOm is CrO, MA is Na and reaction schemes I and III are:

[0357] According to some embodiments, MT is Cr; MTnOm is CrO, MA is K and reaction schemes I and III are:

[0358] According to some embodiments, MT is Cr; MTnOm is CrO3, MA is Na and reaction schemes I and III are:

[0359] According to some embodiments, MT is Cr; MTnOm is CrO3, MA is K and reaction schemes I and III are:

[0360] According to some embodiments, MT is Cr; MTnOm is Cu2O, MA is Na and reaction schemes I and III are:

[0361] According to some embodiments, MT is Cr; MTnOm is Cu2O, MA is K and reaction schemes I and III are:

[0362] According to some embodiments, MT is Cu; MTnOm is CuO, MA is Na and reaction schemes I and III are:

[0363] According to some embodiments, MT is Cu; MTnOm is CuO, MA is K and reaction schemes I and III are:

[0364] According to some embodiments, MT is Cu; MTnOm is CuO2, MA is Na and reaction schemes I and III are:

[0365] According to some embodiments, MT is Cu; MTnOm is CuO2, MA is K and reaction schemes I and III are:

[0366] According to some embodiments, MT is Zn; MTnOm is ZnO, MA is Na and reaction schemes I and III are:

[0367] According to some embodiments, MT is Zn; MTnOm is ZnO, MA is K and reaction schemes I and III are:

[0368] According to some embodiments, MT is Mn; MTnOm is MnO, MA is Na and reaction schemes I and III are:

[0369] According to some embodiments, MT is Mn; MTnOm is MnO, MA is K and reaction schemes I and III are:

[0370] According to some embodiments, MT is Mn; MTnOm is Mn3O4, MA is Na and reaction schemes I and III are:

[0371] According to some embodiments, MT is Mn; MTnOm is Mn3O4, MA is K and reaction schemes I and III are:

[0372] According to some embodiments, MT is Mn; MTnOm is Mn2O3, MA is Na and reaction schemes I and III are:

[0373] According to some embodiments, MT is Mn; MTnOm is Mn2O3, MA is K and reaction schemes I and III are:

[0374] According to some embodiments, MT is Mn; MTnOm is MnO2, MA is Na and reaction schemes I and III are:

[0375] According to some embodiments, MT is Mn; MTnOm is MnO2, MA is K and reaction schemes I and III are:

[0376] According to some embodiments, MT is Mn; MTnOm is Mn2O7, MA is Na and reaction schemes I and III are:

[0377] According to some embodiments, MT is Mn; MTnOm is Mn2O7, MA is K and reaction schemes I and III are:

[0378] According to some embodiments, MT is Sc; MTnOm is Sc2O3, MA is Na and reaction schemes I and III are:

[0379] According to some embodiments, MT is Sc; MTnOm is Sc2O3, MA is K and reaction schemes I and III are:

[0380] According to some embodiments, MT is Ti; MTnOm is TiO2, MA is Na and reaction schemes I and III are:

[0381] According to some embodiments, MT is Ti; MTnOm is TiO2, MA is K and reaction schemes I and III are:

[0382] According to some embodiments, MT is Ti; MTnOm is Ti2O3, MA is Na and reaction Schemes I and III are:

[0383] According to some embodiments, MT is Ti; MTnOm is Ti2O3, MA is K and reaction Schemes I and III are:

[0384] According to some embodiments, MT is V; MTnOm is VO, MA is Na and reaction schemes I and III are:

[0385] According to some embodiments, MT is V; MTnOm is VO, MA is K and reaction schemes I and III are:

[0386] According to some embodiments, MT is V; MTnOm is V2O3, MA is Na and reaction Schemes I and III are:

[0387] According to some embodiments, MT is V; MTnOm is V2O3, MA is K and reaction Schemes I and III are:

[0388] According to some embodiments, MT is V; MTnOm is VO2, MA is Na and reaction schemes I and III are:

[0389] According to some embodiments, MT is V; MTnOm is VO2, MA is K and reaction schemes I and III are:

[0390] According to some embodiments, MT is V; MTnOm is V2O5, MA is Na and reaction Schemes I and III are:

[0391] According to some embodiments, MT is V; MTnOm is V2O5, MA is K and reaction Schemes I and III are:

[0392] According to some embodiments, MT is Co; MTnOm is Co2O3, MA is Na and reaction schemes I and III are:

[0393] According to some embodiments, MT is Co; MTnOm is Co2O3, MA is K and reaction schemes I and III are:

[0394] According to some embodiments, MT is Co; MTnOm is CoO, MA is Na and reaction schemes I and III are:

[0395] According to some embodiments, MT is Co; MTnOm is CoO, MA is K and reaction schemes I and III are:

[0396] According to some embodiments, MT is Co; MTnOm is Co3O4, MA is Na and reaction schemes I and III are:

[0397] According to some embodiments, MT is Co; MTnOm is CO3O4, MA is K and reaction schemes I and III are:

[0398] According to some embodiments, there is provided a process for the reduction of an iron metal oxide, the process comprising:

[0399] (a) providing iron oxide having the formula FenOm, wherein each one of n and m is 1, 2, 3, 4, 5, 6 or 7;

[0400] (b) contacting the iron oxide with sodium metal in a reactor, adjusting the temperature within the reactor to a first temperature in the range of 250° C. to 650° C., to induce a reaction according to scheme I:elevating the temperature to a second temperature, which is at least 50° C. higher than the reduction temperature, to induce a reaction according to scheme II:so that a net reaction, III, resulting from the reactions of schemes I and II, does not consume the sodium metal:wherein a resulting reaction mixture comprises a reduced iron metal, sodium, and optionally oxygen and / or sodium oxide Na2O; and(c) isolating the iron from the reaction mixture.Specific reference is now made to step (a) of the present process, which comprises providing at least one transition metal oxide, according to some embodiments.According to some embodiments, step (a) comprises providing at least one transition metal oxide having the formula MTnOm. According to some embodiments, step (a) comprises providing a transition metal oxide having the formula MTnOm. According to some embodiments, step (a) comprises providing a single transition metal oxide having the formula MTnOm. According to some embodiments, step (a) comprises providing iron oxide having the formula FenOm. According to some embodiments, step (a) comprises providing a single iron oxide having the formula FenOm.Specifically, as can be understood by the person having ordinary skill in the art, provision of more than one transition metal oxide of formula MTnOm in step (a) can lead, according to some embodiments, to formation of a transition metal alloy upon completion of the present process, as elaborated herein. Alternatively, according to some embodiments, provision of one transition metal oxide of formula MTnOm in step (a) can lead to the formation of a reduced transition metal upon completion of the present process. Particularly, if the reaction mixture of step (b) contains no metals or metal oxides, which are alloyable with the transition metal provided in step (a), the result of the two-reaction sequence of step (b) will be a transition metal, according to some embodiments. However, if another metal, which is alloyable with the transition metal provided in step (a), or an oxide of such alloyable metal is present in the reaction mixture of step (b), an alloy may form from the two metals.According to some embodiments, n is 1, 2, 3, 4, 5, 6 or 7. Each possibility represents a separate embodiment of the invention. According to some embodiments, n is 1, 2 or 3. According to some embodiments, m is 1, 2, 3, 4, 5, 6 or 7. Each possibility represents a separate embodiment of the invention. According to some embodiments, m is 1, 2, 3 or 4.

[0409] According to some embodiments, MT is elected from the group consisting of: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn. Each possibility represents a separate embodiment of the invention. According to some embodiments, the transition metal is Sc. According to some embodiments, the transition metal is Ti. According to some embodiments, the transition metal is V. According to some embodiments, the transition metal is Cr. According to some embodiments, the transition metal is Mn. According to some embodiments, the transition metal is Fe. According to some embodiments, the transition metal is Co. According to some embodiments, the transition metal is Ni. According to some embodiments, the transition metal is Cu. According to some embodiments, the transition metal is Zn.

[0410] According to some embodiments, the transition metal oxide is provided in step (a) as a solid.

[0411] As detailed herein, during step (b) the transition metal oxide is consumed to provide a transition metal and oxygen, whereas the alkali metal is preserved and recycled, according to some embodiments. This enables to continuously provide additional transition metal oxide into the reaction mixture and to continuously obtain additional transition metal.

[0412] According to some embodiments, step (a) comprises continuously providing the at least one transition metal oxide into the reactor, so that the total transition metal oxide provided in step (a) is in molar excess over the alkali metal of step (b). According to some embodiments, step (a) comprises gradually providing the at least one transition metal oxide into the reactor. It is to be understood that at any time during step (b) the alkali metal may within the reactor be in molar excess over the transition metal oxide therein, according to some embodiments, however, according to the present embodiment, the transition metal oxide is continuously added and consumed so that the total transition metal oxide provided over the time is in molar excess over the alkali metal catalyst.

[0413] For purposes of this specification, the term “continuously” means that the transition metal oxide is added to the reactor over time. The term is not limited to uninterrupted or interrupted (e.g., batch) addition of the transition metal oxide.

[0414] According to some embodiments, the molar excess is at least 50% mol / mol, at least 100% mol / mol, at least 200% mol / mol, at least 300% mol / mol, at least 400% mol / mol, at least 500% mol / mol, at least 750% mol / mol, at least 1,000% mol / mol, at least 2,000% mol / mol, at least 5,000% mol / mol or at least 10,000% mol / mol. Each possibility represents a separate embodiment of the invention. According to some embodiments, the molar excess is in the range of 100% to 1,000,000% mol / mol, 500% to 1,000,000% mol / mol, 1,000% to 1,000,000% mol / mol or 10,000% to 1,000,000% mol / mol. Each possibility represents a separate embodiment of the invention and including each value and sub-range within the specified range.

[0415] It is to be understood that molar excess of X % as used in the context of steps (a) and (b) means that the total mole amount of transition metal oxide eventually added in step (a) surpasses the mole amount of the alkali metal used by X %.

[0416] According to some embodiments, the at least one transition metal oxide is as detailed herein above with respect to step (1).

[0417] According to some embodiments, step (a) comprises providing an ore, which comprises the transition metal oxide. According to some embodiments, step (a) comprises providing an ore, which comprises the iron oxide. According to some embodiments, the ore is as described in step (1).

[0418] According to some embodiments, MTnOm is as described in step (1).

[0419] Specific reference is now made to step (b) of the present process, which comprises combining the transition metal oxide with an alkali metal (MA) in a reactor, and adjusting the temperature within the reactor to the first temperature.

[0420] According to some embodiments, step (b) comprises contacting the iron oxide with sodium metal in a reactor, adjusting the temperature within the reactor to a first temperature in the range of 100° C. to 500° C., to induce a reaction according to scheme I:elevating the temperature to a second temperature, which is at least 50° C. higher than the reduction temperature, to induce a reaction according to scheme II:so that a net reaction, III, resulting from the reactions of schemes I and II, does not consume the sodium metal:wherein a resulting reaction mixture comprises a reduced iron metal, sodium, and optionally oxygen and / or sodium oxide Na2O.According to some embodiments, step (b) comprises contacting the at least one transition metal with an alkali metal in a reactor, adjusting the temperature within the reactor to a first temperature which is above the melting point of the alkali metal in the range of 100° C. to 500° C., to induce a reaction according to scheme I:resulting in a reaction mixture, which comprises a reduced transition metal, MT, or alloy thereof, an alkali metal oxide MA2O, and optionally oxygen and / or the alkali metal, MA;wherein MA is Na or K or alloys thereof;According to some embodiments, step (b) comprises combining the transition metal oxide with an alkali metal (MA). According to some embodiments, the action of combining the transition metal oxide with an alkali metal is performed at the first temperature. Specifically, in the case that the reaction has not yet started, external heating is required to reach the first temperature, according to some embodiments. Alternatively, after the reaction has begun, its exothermicity can at least partially maintain or elevate the internal temperature, so that less external heating is required or even the external heating may be at least temporarily ceased, according to some embodiments.According to some embodiments, adjusting the temperature within the reactor to a first temperature comprises elevating the temperature within the reactor to the first temperature. According to some embodiments, step (b) comprises adjusting the temperature by induction.It is to be understood that in case that the process includes the separation of the sodium oxide and further dissociation thereof into its elements (in step (e)), embodiments herein, which refer to the reaction of scheme II may refer either to this reaction in step (b) or in step (e).According to some embodiments, the value of the first temperature is selected such that the reactions of scheme I is conducted. In other words, the first temperature brings enough energy to the reaction system to surpass the activation energy of both reactions and provides adequate reaction conditions.For the reaction of Scheme I, a key parameter is the physical state of the reactants, according to some embodiments. Specifically, according to some embodiments, it is advantageous that the reactions of the present method are conducted neat (i.e., without any solvents). Also, at room temperature both the alkali metal and the transition metal oxide reactants are in the solid state, which tends to slow-down or prevent chemical reactions.For the reaction of Scheme II, a key parameter is the activation energy required to decompose the alkali metal oxide, according to some embodiments. Therefore, according to some embodiments, the second temperature is equal or above the decomposition temperature of MA2O under that reactor-specific conditions. According to some embodiments, the second temperature is above the decomposition temperature of MA2O.

[0428] The term “alkali metal” is as described hereinabove with reference to step (2). According to some embodiments, the alkali metal (MA) is as described hereinabove with reference to step (2).

[0429] According to some embodiments, the first temperature is as described with respect to step (2).

[0430] According to some embodiments, the reaction of scheme II takes place wherein sodium oxide is in the solid phase.

[0431] According to some embodiments, the reaction of scheme II takes place wherein sodium oxide is in the gas phase, wherein step (b) further entails at least partially evaporating the sodium oxide. According to some embodiments, upon decomposition of the sodium oxide, the resulting products, sodium and oxygen are initially in the gas phase.

[0432] According to some embodiments, the reaction of Scheme I is conducted neat. According to some embodiments, the reaction of Scheme II is conducted neat. According to some embodiments, the two-reaction sequence of step (b) is conducted neat. According to some embodiments, the reaction mixture of step (b) is substantially devoid of additional solvents. According to some embodiments, the reaction mixture of step (b) is substantially devoid of additional solvents and carriers.

[0433] According to some embodiments, the reaction mixture of step (b) is consisting essentially of the transition metal oxide, the alkali metal and the product reduced transition metal or alloy thereof. According to some embodiments, the condensed phase within the reactor during step (b) is consisting essentially of the transition metal oxide, the alkali metal and the product reduced transition metal or alloy thereof.

[0434] According to some embodiments, the reaction mixture of step (b) is consisting essentially of the iron oxide, the sodium and, optionally, the products, iron and / or sodium oxide.

[0435] According to some embodiments, net reaction, III, resulting from said two-reaction sequence does not consume the alkali metal. According to some embodiments, the alkali metal is used and recycled in the two-reaction sequence of step (b). According to some embodiments, the alkali metal is recycled in the two-reaction sequence of step (b).

[0436] According to some embodiments, the resulting reaction mixture formed upon contacting the transition metal oxide and alkali metal in step (b) is in a fluid state. According to some embodiments, the resulting reaction mixture formed upon contacting the transition metal oxide and alkali metal in step (b) is in a liquid state. According to some embodiments, the resulting reaction mixture formed upon contacting the transition metal oxide and alkali metal in step (b) is a heterogenous mixture. According to some embodiments, the resulting reaction mixture formed upon contacting the transition metal oxide and alkali metal in step (b) is a liquid-solid, liquid-liquid, gas-solid or gas-liquid heterogenous mixture. Each possibility represents a separate embodiment of the invention.

[0437] According to some embodiments, the reaction mixture formed upon conducting the two-reaction sequence of step (b) comprises the reduced transition metal, MT, or alloy thereof. According to some embodiments, the reaction mixture formed upon conducting the two-reaction sequence of step (b) further comprises oxygen. According to some embodiments, oxygen gas is separated from the reaction mixture.

[0438] According to some embodiments, the reaction mixture of step (b) contains no metals or metal oxides, which are alloyable with the transition metal provided in step (a).

[0439] According to some embodiments, the reaction mixture of step (b) contains alloyable metals or metal oxides, which are alloyable with the transition metal provided in step (a). This is elaborated below when relating to the optional alloy formation.

[0440] As detailed herein, step (a) may involve continuous addition of transition metal oxide to the reaction mixture of step (b) so that over the entire course of step (b) the transition metal oxide is provided in a molar excess over the alkali metal added. Specifically, according to some embodiments, the transition metal oxide added to the reactor over the course of step (b) is in molar excess of the alkali metal added thereto. Specific excesses are specified above.

[0441] However, the transition metal oxide added to the reactor is consumed through the reaction of scheme I, while the alkali metal is recycled through the reaction of scheme I. Therefore, according to some embodiments, at any specific time during step (b) the alkali metal within the reactor is in molar excess over the transition metal oxide. According to some embodiments, the transition metal oxide is continuously provided to the reactor at an addition rate, which ensures that the alkali metal within the reactor is in molar excess over the transition metal oxide at any specific time during step (b). According to some embodiments, the molar excess is at least 5%, least 10%, least 25%, least 50%, least 100% or least 200%. Each possibility represents a separate embodiment of the invention.

[0442] According to some embodiments, the reactor in which step (b) is taking place comprises a crucible. According to some embodiments, step (b) comprises contacting the iron oxide with sodium metal in the crucible. According to some embodiments, step (a) is taking place in the crucible. According to some embodiments, step (b) comprises contacting the transition metal oxide with alkali metal in the crucible. According to some embodiments, the crucible is as described in step (2).

[0443] According to some embodiments, adjusting the temperature within the reactor in step (b) comprises gradually elevating the temperature in the reactor to the first temperature. According to some embodiments, elevating the temperature to the first temperature is performed at a rate as defined in step (2).

[0444] According to some embodiments, elevating the temperature within the reactor in step (b) to the second temperature comprises gradually elevating the temperature in the reactor to the second temperature. According to some embodiments, elevating the temperature to the second temperature is performed at a rate as defined in step (4).

[0445] According to some embodiments, step (b) comprises contacting the transition metal oxide with alkali metal at a weight ratio as defined in step (2).

[0446] According to some embodiments, the two-reaction sequence of step (b) is conducted in an air-protected environment. According to some embodiments, the two-reaction sequence of step (b) is conducted in a water-protected environment. According to some embodiments, the two-reaction sequence of step (b) is conducted in an air and water protected environment.

[0447] Specifically, it is to be understood that alkali metals are highly reactive and require specific reaction conditions, such as performance under inert gas.

[0448] According to some embodiments, step (b) further comprises flowing inert gas into the reactor. According to some embodiments, the two-reaction sequence of step (b) is performed under inert gas. According to some embodiments, the inert gas in nitrogen or argon.

[0449] According to some embodiments, during step (b) the reactor is closed. According to some embodiments, during step (b) the reactor is closed under an inert atmosphere. According to some embodiments, during step (b) the reactor is closed under an inert gas atmosphere. According to some embodiments, during step (b) the reactor is closed and the two-reaction sequence is performed at an elevated pressure.

[0450] Advantageously, the reaction duration is short, which is both economical and energy-consuming.

[0451] According to some embodiments, step (b) is performed for no more than 6 hours, no more than 4 hours, no more than 3 hours, no more than 2 hours, no more than 1 hour, no more than 45 minutes, or no more than 30 minutes. Each possibility represents a separate embodiment of the invention. According to some embodiments, step (b) is performed for no more than 1 hour. According to some embodiments, step (b) is performed for at least 5 minutes, at least 10 minutes, at least 15 minutes, at least 20 minutes or at least 25 minutes. Each possibility represents a separate embodiment of the invention.

[0452] It is to be understood that reference to the duration of step (b) refers to an individual run of step (b). Specifically, as detailed herein, according to some embodiments, the present process is performed cyclically, with the alkali metal recycled after the completion of the reaction, back to be re-used in a subsequent run of step (b). thus, it is to be understood that repeats of step (b) are allowed to cumulatively surpass the bottom threshold set above, without contradicting the above clause, which is directed to the individual run of step (b)

[0453] c Specific reference is now made to step (c) of the present process, which comprises isolating the reduced transition metal or alloy thereof, according to some embodiments.

[0454] According to some embodiments, step (c) comprises isolating the reduced transition metal or alloy thereof, from the reaction mixture. According to some embodiments, step (c) comprises isolating the reduced transition metal from the reaction mixture. According to some embodiments, step (c) comprises isolating the reduced transition metal alloy from the reaction mixture. According to some embodiments, step (c) comprises isolating the reduced iron from the reaction mixture.

[0455] According to some embodiments, the isolating comprises evaporating the alkali metal oxide, and optionally oxygen and / or the alkali metal, from the reactor. According to some embodiments, the isolating comprises evaporating the alkali metal oxide from the reactor. According to some embodiments, the isolating comprises evaporating the alkali metal oxide and oxygen from the reactor. According to some embodiments, the isolating comprises evaporating the alkali metal oxide and the alkali metal, from the reactor. According to some embodiments, the isolating comprises evaporating the alkali metal oxide, the oxygen and the alkali metal, from the reactor. According to some embodiments, the isolation of step (c) entails evaporating the sodium metal from the reactor; and the process further comprises step (d) of collecting the isolated iron metal or alloy thereof.

[0456] According to some embodiments, step (c) comprises evaporating the sodium metal, oxygen, and optionally sodium oxide, from the reactor to produce an isolated iron metal.

[0457] According to some embodiments, step (c) comprises first evaporating the oxygen and then evaporating the alkali metal. According to some embodiments, step (c) comprises first evaporating the oxygen and then evaporating the sodium metal.

[0458] According to some embodiments, evaporating the alkali metal is performed at a temperature as detailed in step (5) herein

[0459] According to some embodiments, evaporating the alkali metal is performed at a reduced pressure as specified in step (5) herein.

[0460] According to some embodiments, the evaporating is performed for a time duration as specified with respect to step (5) herein

[0461] According to some embodiments, the isolated reduced transition metal or alloy thereof is in a physical form as described in step (3) herein.

[0462] According to some embodiments, the isolation of step (c) entails evaporating the alkali metal produced in reaction scheme II and transferring the alkali metal out of the reactor, so that the reactor remains with the reduced transition metal or alloy thereof. According to some embodiments, the evaporation involves heating the alkali metal. According to some embodiments, the evaporation involves reducing the pressure within the reactor. According to some embodiments, the isolation of step (c) entails evaporating the alkali metal from the reactor. According to some embodiments, the isolation of step (c) entails boiling the alkali metal from the reactor.

[0463] According to some embodiments, the isolation of step (c) entails evaporating the sodium metal produced in reaction scheme II and transferring the sodium metal out of the reactor, so that the reactor remains with the reduced transition metal or alloy thereof. According to some embodiments, the evaporation involves heating the sodium metal. According to some embodiments, the evaporation involves reducing the pressure within the reactor. According to some embodiments, the isolation of step (c) entails evaporating the sodium metal from the reactor. According to some embodiments, the isolation of step (c) entails boiling the sodium metal from the reactor.

[0464] According to some embodiments, transferring the sodium metal as a gas from the reactor produces an isolated transition metal or alloy thereof.

[0465] Also, in industrial processes, the transition metal oxides may be provided from ores, which contain contaminants, such as silicon oxides (typically, silicon dioxide). When providing such transition metal oxide compositions in step (a) of the present process, they may not react and the contaminants may be separated using an additional step of melting the transition metal product and filtering / skimming off the contaminants.

[0466] According to some embodiments, step (c) comprises isolating the reduced transition metal or alloy thereof, from the reaction mixture, wherein the isolating comprises evaporating the alkali metal oxide, and optionally oxygen and / or the alkali metal, from the reactor; wherein the evaporating comprises applying reduced pressure to the reaction mixture, applying inert gas flow to the reaction mixture, or both.

[0467] According to some embodiments, the evaporating of step (c) comprises applying reduced pressure to the reaction mixture.

[0468] According to some embodiments, the evaporating is carried out at a pressure in the range of 0.001 Bar to 0.5 Bar, including each value and sub-range within the specified range.

[0469] According to some embodiments, the evaporating of step (c) comprises inert gas flow to the reaction mixture.

[0470] Specifically, it was found the application of inert gas flow promotes the evaporation of sodium oxide, below it boiling or decomposition point. Also at this reduced temperature, the sodium oxide was found to be unreactive to iron species, so that sodium-iron oxide formation is avoided, according to some embodiments.

[0471] According to some embodiments, the evaporating of step (c) is performed in parallel to the reaction of step (b). According to some embodiments, the evaporating of step (c) is performed at least partially in parallel to the reaction of step (b). The phrase “evaporating of step (c) is performed at least partially in parallel to the reaction of step (b)” means that at least some of the duration of step (b) and at least some of the duration of step (c) are concurrent.

[0472] Specifically, according to some embodiments, it is beneficial that the alkali metal oxide and the oxygen are quickly removed from the reaction mixture to increase the reaction rate.

[0473] According to some embodiments, the evaporating of step (c) is performed after the reaction of step (b).

[0474] According to some embodiments, the evaporating of step (c) is performed in parallel to the reaction of scheme I. According to some embodiments, the evaporating of step (c) is performed at least partially in parallel to the reaction of scheme I. According to some embodiments, the evaporating of step (c) is performed after the reaction of scheme I.

[0475] According to some embodiments, evaporating the alkali metal oxide from the reactor in step (c) is performed at about the first temperature. According to some embodiments, evaporating the alkali metal oxide from the reactor in step (c) is performed at a temperature, which is in the range of ±100° C. of the first temperature. According to some embodiments, evaporating the alkali metal oxide from the reactor in step (c) is performed at a temperature, which is in the range of ±50° C. of the first temperature. According to some embodiments, evaporating the alkali metal oxide from the reactor in step (c) is performed at a temperature, which is in the range of ±25° C. of the first temperature. According to some embodiments, evaporating the alkali metal oxide from the reactor in step (c) is performed at a temperature, which is in the range of ±15° C. of the first temperature. According to some embodiments, evaporating the alkali metal oxide from the reactor in step (c) is performed at a temperature, which is in the range of ±10° C. of the first temperature. According to some embodiments, evaporating the alkali metal oxide from the reactor in step (c) is performed at a temperature, which is in the range of ±5° C. of the first temperature.

[0476] d Specific reference is now made to step (d) of the present process. As detailed above, steps (a)-(c) include several variations. A First Main Variation includes performing the reactions of schemes I and II (and III), so that the product iron is isolated in step (c) from a reaction mixture that includes the iron, sodium and optionally, oxygen. A Second Main Variation includes performing the reaction of scheme I, so that the product iron is isolated in step (c) from a reaction mixture that includes the iron, sodium oxide and optionally, sodium. The action(s) of the step(s), which follow step (c) depend on the route taken.

[0477] Thus, reference is now made to step (d) of the First Main Variation.

[0478] In particular, step (d) is optional and comprises condensing the alkali metal evaporated during step (c). According to some embodiments, step (d) comprises condensing the sodium evaporated during step (c).

[0479] According to some embodiments, the process further comprises step (d) of condensing the evaporated alkali metal. According to some embodiments, the evaporated alkali metal is condensed in a dedicated container. According to some embodiments, the container is kept at air- and / or water-protected conditions. According to some embodiments, the container is a sealable container.

[0480] According to some embodiments, the process further comprises step (d) of condensing the evaporated sodium metal. According to some embodiments, the evaporated sodium metal is condensed in a dedicated container. According to some embodiments, the container is kept at air- and / or water-protected conditions. According to some embodiments, the container is a sealable container. The sodium metal container is discussed below with respect to the system.

[0481] In general, alkali metals are solid materials at room temperature and atmospheric pressure. In step (c) the alkali metals are heated, and optionally put in reduced pressure, so that they transform into vapor, according to some embodiments. Step (d) is relevant when the isolation of step (c) comprises such vaporization, and it comprises the condensation of the alkali metal vapor in a separate container, according to some embodiments. Although the term “condense” typically refers to the transformation from gas to liquid, it is to be understood that the condensed alkali metals may gradually or instantaneously transform into solids, depending, e.g., on the temperature in the alkali metal container. Thus, the term “condense” in the context of step (e) further comprises deposition of gas to solid.

[0482] Reference is now made to step (d) of the Second Main Variation.

[0483] Step (d) of the Second Main Variation, as detailed herein, may be divided into two sub-steps, step (d1), directed to condensing the transition metal oxide evaporated in step (c), and step (d2), which is directed to dissociating the condensed transition metal oxide into its corresponding elements, according to some embodiments.

[0484] Reference is now made to step (d1).

[0485] According to some embodiments, the process further comprises step (d1) of condensing the evaporated alkali metal oxide into a condensation container. According to some embodiments, the process further comprises step (d1) of condensing the evaporated alkali metal oxide and, optionally, the alkali metal of step (c), into a condensation container. According to some embodiments, the process further comprises step (d1) of condensing the evaporated alkali metal oxide and the alkali metal of step (c), into a condensation container.

[0486] According to some embodiments, the condensation of step (d1) is performed at a temperature which is lower than the first temperature. According to some embodiments, the condensation of step (d1) is performed at a temperature which is at least 100° C. lower than the first temperature. According to some embodiments, the condensation of step (d1) is performed at a temperature which is at least 200° C. lower than the first temperature. According to some embodiments, the condensation of step (d1) is performed at a temperature which is at least 250° C. lower than the first temperature. According to some embodiments, the condensation of step (d1) is performed at a temperature which is at least 300° C. lower than the first temperature. According to some embodiments, the condensation of step (d1) is performed at a temperature which is at least 350° C. lower than the first temperature. According to some embodiments, the condensation of step (d1) is performed at a temperature which is at least 400° C. lower than the first temperature.

[0487] According to some embodiments, the pressure within the condensation container is as described in step (6).

[0488] Reference is now made to step (d2) which may follow step (d1), according to some embodiments.

[0489] According to some embodiments, the process further comprises step (d2) of heating the condensed alkali metal oxide of step (d1) to a second temperature to induce a reaction according to scheme II:

[0490] so that a net reaction, III, resulting from the reactions of schemes I and II does not consume the alkali metal:

[0491] The second temperature and the reactions of Schemes II and III are described in detail when relating to step (b) of the First Main Variation.

[0492] e Specific reference is now made to step (e) of the present process, which is optional and comprises transferring the alkali metal condensed in step (e) back into the reactor. In particular, since, in this stage both the First Main Variation and Second Main Variation of the present process already conducted both reactions (I and II) to produce the alkali metal, the reclamation of the alkali metal can be made in both variation in step (e).

[0493] According to some embodiments, the process comprises step (e) of transferring the alkali metal formed in step (d) into the reactor. It is to be understood that the phrase “transferring the alkali metal formed in step (d)” may refer to the alkali metal (e.g., sodium) formed in step (d) according to the First Main Variation or to the alkali metal formed in step (d2) according to the Second Main Variation, depending on the context and recited preceding steps.

[0494] According to some embodiments, the process comprises step (e) of transferring the sodium metal formed in step (d) back into the reactor. According to some embodiments, step (e) comprises transferring the condensed alkali metal into the reactor, thereby recycling the alkali metal. According to some embodiments, step (e) comprises transferring the condensed sodium metal into the reactor, thereby recycling the sodium metal.

[0495] According to some embodiments, the alkali metal is transferred to the reactor in step (e) as a condensed material. According to some embodiments, the alkali metal is transferred to the reactor in step (e) as a liquid. According to some embodiments, the alkali metal is transferred to the reactor in step (e) as a solid.

[0496] It is to be understood that by performing step (e), one cycle of the present process is complete. Upon the reconstitution of alkali metal and additional provision of transition metal oxide, the process may continue to an additional cycle, according to some embodiments.

[0497] According to some embodiments, the process further comprises repeating steps (a)-(d) for at least one additional sequence after step (f). According to some embodiments, the process further comprises repeating steps (a)-(d1) for at least one additional sequence after step (f). According to some embodiments, the process further comprises repeating steps (a)-(d2) for at least one additional sequence after step (f). According to some embodiments, the process further comprises repeating steps (a)-(c) for at least one additional sequence after step (f). According to some embodiments, the process further comprises repeating steps (a)-(c) for at least one additional sequence. According to some embodiments, the process further comprises repeating steps (a)-(d) for at least one additional sequence. According to some embodiments, the process further comprises repeating steps (a)-(d1) for at least one additional sequence. According to some embodiments, the process further comprises repeating steps (a)-(d2) for at least one additional sequence.

[0498] According to some embodiments, the process comprises: performing steps (a)-(f) for at least one cycle and performing steps (a)-(c). According to some embodiments, the process comprises: performing steps (a)-(f) for a plurality of cycles and performing steps (a)-(c).

[0499] f Specific reference is now made to step (f) of the present process, which comprises isolating the transition metal or alloy thereof. In particular, it is to be understood that step (f) can be made in both variation in step (e).

[0500] Specifically, according to some embodiments, the process further comprises collecting the isolated transition metal or alloy thereof produced in step (c). Specifically, according to some embodiments, the process further comprises collecting the isolated iron produced in step (c).

[0501] According to some embodiments, the isolation of step (c) entails evaporating the alkali metal from the reactor; and the process further comprises step (f) of collecting the isolated transition metal or alloy thereof. According to some embodiments, the isolation of step (c) entails evaporating the sodium metal from the reactor; and the process further comprises step (f) of collecting the isolated iron metal.

[0502] Reference is now made to FIGS. 7-8, which are block diagrams representing a process for the reduction of at least one transition metal oxide into the corresponding transition metal or alloy thereof.

[0503] Specifically, FIG. 7 is a block diagram representing a process for the reduction of at least one iron oxide into the corresponding iron, which comprises steps (a), (b) and (c) as detailed herein, according to some embodiments. Step (a) is represented by block 1000, step (b) is represented by block 1010 and step (c) is represented by block 1020.

[0504] Similarly, FIG. 8 is a block diagram representing a process for the reduction of at least one iron oxide into the corresponding iron, which comprises steps (a), (b), (c), (d), (e) and (f) as detailed herein, according to some embodiments. Step (a) is represented by block 1000, step (b) is represented by block 1010, step (c) is represented by block 1020, step (f) is represented by block 1030, step (d) is represented by block 1040 and step (e) is represented by block 1050.

[0505] Similarly, FIG. 9 is a block diagram representing a process for the reduction of at least one transition metal oxide into the corresponding transition metal, which comprises steps (a), (b), (c), (d1), (d2), (e) and (f) as detailed herein, according to some embodiments. Step (a) is represented by block 1000, step (b) is represented by block 1010, step (c) is represented by block 1025, step (f) is represented by block 1030, step (d1) is represented by block 1040, step (d2) is represented by block 1045 and step (e) is represented by block 1050.

[0506] Below are provided non-limiting specific embodiments of specific reaction sequences, which can be conducted by the processes of the present invention. Reference in further made to FIGS. 10-12 which are block diagrams, each representing a selected process for the reduction of at least one transition metal oxide into the corresponding transition metal or alloy thereof (i.e., a specific two-reaction sequence). Each one of FIGS. 4-6 represent a process comprising steps (a), (b) and (c) as detailed herein, according to some embodiments, wherein step (a) is represented by block 1000, step (b) is represented by block 1010 and step (c) is represented by block 1020. Relevant specific examples are presented above in the section that relates the FIGS. 4-6.

[0507] Specific reference is now made to embodiments of the present process, which are directed to the formation of a transition metal alloy.

[0508] According to some embodiments, the process is for the preparation of a metal alloy, wherein step (a) or step (b); or step (1) or step (2), further comprises providing a second metal, Mb into the reactor, wherein the second metal is alloyable with MT; step (b) or step (2) comprises combining the second metal with the alkali metal and the transition metal oxide to induce the reaction as detailed herein, and further induce the reaction of scheme IV:

[0509] According to some embodiments, the second metal, Mb, is not an alkali metal. According to some embodiments, the second metal, Mb, is a transition metal, MTb.

[0510] The term “alloyable” refers to the capability of two metal elements to form an alloy. Thus, the term “alloyable metal”, as used herein refers to any metal, which is capable of forming an alloy with the transition metal formed in the process of the present invention. According to some embodiments, the alloyable metal forms an alloy with the transition metal formed in the conditions of process of the present invention (i.e., the conditions of step (b) or (2).

[0511] Also, the alloyable metal may be provided as a metal oxide and be reduced under the present process reaction conditions (i.e., reduced by the alkali metal), according to some embodiments.

[0512] According to some embodiments, the process is for the preparation of a metal alloy, wherein step (a) or (1) comprises further providing a second metal oxide having the formula MbiOj, wherein each one of i and j is 1, 2, 3, 4, 5, 6 or 7; and step (b) or (2) comprises combining the two metal oxides with the alkali metal, wherein reaction schemes I and III are:and wherein step (b) further induced reaction IV of forming the alloy:It is to be understood that reaction Scheme I is spitted into Ia and Ib, while reaction Scheme III is spitted into IIIa and IIIb.

[0515] According to some embodiments, the second metal, Mb, is a transition metal, MTb.

[0516] Thus, according to some embodiments, step (a) or (1) comprises providing at least two transition metal oxides having the formulas MTanOm and MTbiOj, wherein each one of i and j is 1, 2, 3, 4, 5, 6 or 7, wherein each one of MTa, MTb is a transition metal selected from the group consisting of: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn; and step (b) or (2) comprises combining the transition metal oxides with the alkali metal, wherein reaction schemes I and III are:and wherein step (b) or (2) further induced reaction IV of forming the alloy:According to some embodiments, the transition metal alloy formed by any one of the processes of the present invention is selected from the group consisting of: Brass (CuZn), Constantan (CuNi), Cunife (CuNiFe or CuNiFeCo), Cupronickel (CuNiFe or CuNiMn), Manganin (CuMnNi), Maillechort (CuNi or CuNiZn), Elinvar (NiFeCr), Fernico (FeNiCo), Ferromanganese (FeMn), Ferronickel (FeNi), Ferrotitanium (FeTi), Ferrovanadium (FeV), Invar (FeNi), Kovar (FeNiCo), Chromel (NiCr) and Nitinol (NiTi).EXAMPLESGeneral Procedure—System

[0519] Reaction between several metal oxides with pure sodium at 900° C. for the reduction of the metal oxide to pure metal. The Fe2O3 metal oxide was tested.System Components:1. Reactor—SS304 265 mL custom made.

[0521] 2. 304 SS crucible 25 mL.

[0522] 3. First induction heating system (Chinese 6 kw), Induction coil (5 turns).

[0523] 4. Second induction system (Chinese 3 kw), Induction coil (3 turns).

[0524] 5. The system was cooled with one water chiller.

[0525] 6. SS304 tube 430 mL (sodium disposal reactor) and flange (NW50).

[0526] 7. Parker connectors for argon insert.

[0527] 8. Thermocouple type K (3—one outside ½″ connection, one in reactor, one in crucible).

[0528] 9. Argon flow controller company “AALBORG”.

[0529] 10. Three on\off valves 1\4″ and one vacuum valve.

[0530] 11. Bellow trap with ss wool to protect the vacuum pump.

[0531] 12. Vacuum pump.

[0532] 13. Stands.

[0533] 14. Thermal insulating wool.

[0534] The material structure of the reaction reactor is SS304 with a volume of 265 mL was connected through a ½″ SS316 tube to the sodium disposal reactor with material structure of SS304 with volume of 430 mL with crucible made of 304 SS was placed inside the reaction reactor.

[0535] To protect the inductio' systems and the o'ring in the KF flange a protection of alumina block used in critical location.General Experimental Procedure

[0536] In the reaction reactor placed crucible with 3 gr of metal oxide and 3 gr of pure sodium. One thermocouple placed inside the reactor to control the first induction system, and a second thermocouple placed inside the crucible to measure the reaction, both connected to data logger.

[0537] The first induction system heats the lower part of the reaction reactor where the crucible was placed, to 600° C., with a heating rate of 15° C. / min and argon flow of 40 mL / min during the experiments.

[0538] At the start of the reaction the vacuum valve and a second argon outlet valve are closed, and the argon flow outlet is through a first argon outlet valve. When the temperature reached 500° C., the first argon outlet valve was closed and the second valve was opened. Furthermore, when the first induction system reached 700° C., the second induction system was turned on to reach up 200° C. After 70 minutes from the beginning of the reaction, vacuum to 0.1 bar was initiated using the pump slowly until reaching 0.1 Bar at 600° C. for 2 hours. After 30-minutes, argon was introduced at a flow rate of 40 mL / min. When the pressure in the system reached 14.6 psi, the first argon outlet was opened and the induction systems were turned off.Example 1: Reaction of Iron Ores with Metallic Sodium

[0539] The reaction of metallic sodium with four iron ores (ORE1, ORE2, ORE3 and ORE4) was conducted according to the General Experimental Procedure described above. The ores contained varying concentrations of different iron oxides, including hematite (Fe2O3), magnetite (Fe3O4) and goethite (FeOOH), as well as other compounds such as nacrite (Al2Si2O5(OH)4), silicon dioxide (SiO2), magnesium silicon hydroxide (MgSi(OH)6 and aluminium hydroxide (Al(OH)3) (Table 1).

[0540] The temperature profiles of the four reactions are shown in FIG. 13, and it can be seen that the exotherm occurred at approximately the same temperature of 500° C. However, the reduction reactions with ORE1 and ORE3 experienced higher temperature rises during the exotherm, reaching approximately 850° C. and 700° C. The reaction with ORE2 had a more modest increase to 620° C. while ORE4 did not exhibit a meaningful temperature increase. The XRD results for the reactions of the metallic sodium with ORE1, ORE2, ORE3 and ORE4 sodium are shown in FIGS. 14, 15, 16 and 17, respectively.TABLE 1Composition of iron ores ORE1, ORE2, ORE3and ORE4 determined via XRD analysis.CompoundORE1ORE2ORE3ORE4NameFormula[%][%][%][%]HematiteFe2O369.875.285.943.7MagnetiteFe3O43.715—1.9GoethiteFeOOH13.70.4—42.9NacriteAl2Si2O5(OH)41.76.13.22.2Silicon dioxideSiO27.11.810.89.3MagnesiumMgSi(OH)63.9———SiliconHydroxideAluminiumAl(OH)3—1.5hydroxideSum99.910099.9100[%]—wt % of the compoundExample 2: Reduction of Fe2O3 in Stainless Steel (SS Type 304) and Silicon Carbide (SiC) Crucibles

[0541] The reduction of Fe2O3 into iron metal using sodium was conducted as detailed above in the General Experimental Procedure. Two separate reactions were carried out, with one reaction performed in a stainless steel (SS type 304) crucible and the other in a silicon carbide (SiC) crucible. The temperature profiles of the two reactions are shown in FIG. 18, where it can be observed that exotherms occurred at approximately the same temperature, but a higher temperature rise was observed in the SS crucible (~550° C. vs ~650° C., respectively)

[0542] The XRD results for the two reactions are shown in FIGS. 19 and 20. As shown from the diffractogram, the final product from the reaction with the SS crucible primarily contained different types of sodium iron oxides, with a relatively low selectivity to pure iron (11.5 wt %). This suggests that the reactivity between the sodium substrate and the SS crucible is somehow related to the increased formation of these undesired sodium iron oxides.

[0543] In contrast, the reaction with the SiC crucible was more favorable in producing pure iron with nearly 5 times more of this product (wt %) compared to the SS crucible. The percentage of metallization of the reaction can be calculated when referring to the percentage of metallic iron compared to the general iron in the example, determined to be 89%.Example 3: Isolation of Fe by Evaporation of Sodium Metal Oxide Under Vacuum and / or Argon Flow

[0544] The General Procedure was modified to first evaporate the sodium oxide metal out of the reactor. A reduction reaction, following the General Experimental Procedure, was performed using 20 grams of Fe2O3 and 20 grams of sodium metal. The reactor was then heated to 600° C. to evaporate the sodium oxide, which was carried out using two different methods: under vacuum and under argon gas flow. Following evaporation, the iron metal was collected as a final product.Example 4: Recovery of Sodium Metal from Evaporated Sodium Oxide

[0545] For further treatment and dissociation of the sodium oxide of Example 3 into its constituent elements, sodium and oxygen, the evaporated sodium oxide was transferred out of the reactor and condensed in a condensation container with a temperature of approximately 200° C.Example 5: Scaled-Up Reaction of Iron Ores with Metallic Sodium

[0546] A scaled-up using 20 grams of metallic sodium and 20 grams of iron ore in a 100-gram stainless steel crucible reactor was then performed according to the modified general procedures of Example 3 and Example 4. The temperature profile of the reaction is shown in FIG. 21A, and it can be seen that the exotherm occurred at about 260° C., which is approximately 200° C. lower than what was observed in the smaller scale reaction in Example 1. The exotherm peak was also maintained for a longer period, resulting in a broader peak. The XRD result for this reaction is shown in FIG. 21A.Example 6: Reaction of Low-Grade Iron Ores with Metallic Sodium

[0547] A reaction between low-grade iron ore and metallic sodium was conducted according to step (2) of the present process. In the reactor were placed a crucible and 2.5 gr of iron oxide (50:50 wt / wt mix of hematite and silica) and 2.5 gr of pure sodium. One thermocouple was placed inside the reactor to control the first induction system, and a second thermocouple was placed inside the crucible to measure the reaction, both connected to data logger.

[0548] The first induction system heated the lower part of the reaction reactor where the crucible was placed, to 600° C., at a heating rate of 10° C. / min. Argon flow of 100 mL / min was maintained through the reactor during the experiment.

[0549] At the beginning of the reaction the vacuum valve and a second argon outlet valve were closed, and the argon flow outlet was through a first argon outlet valve. 90 minutes after the beginning of the reaction the systems were turned off.

[0550] The product was in powder form and analysis revealed that sodium oxide was formed and reacted with silica to form sodium silicates. The product consisted of iron—36% (wt % out of sample tested in XRD), sodium silicates 64%. Metallization—100% (weight of converted iron / weight of initial entire iron content), high silica content can react with sodium oxide to create sodium silicates.

[0551] The XRD result for this reaction is shown in FIG. 22.Example 7: Reaction of Iron Ores with Metallic Sodium Under Nitrogen Flow

[0552] A reaction between iron ore and metallic sodium was conducted according to step (2) of the present process. In the reactor were placed a crucible and 2 gr of iron oxide mixture (predominantly hematite) and 3.8 gr of pure sodium. The thermocouple placed inside the wall of the crucible to control the induction system.

[0553] Before heating the system, nitrogen gas flowed through the system for an hour at a flow rate of 400 mL / min. During the system heating phase the induction system heated the reactor where the crucible was placed, to 400° C., at a heating rate of 15° C. / min. Nitrogen flow of 100 mL / min was maintained during the experiment. After the system was heated to 400° C., the system was left at this temperature for two hours. Then, the evaporation phase began, the nitrogen outlet was closed and the vacuum pump was turned on for an hour. After the evaporation phase, the vacuum pump and heating system were turned off and the system cooled. When the pressure in the system reached 14.6 psia, the nitrogen outlet was opened.

[0554] The product was powder form. Iron—39.4% (w % out of sample tested in XRD), Metallization—90% (weight of converted iron / weight of initial entire iron content)

[0555] The XRD result for this reaction is shown in FIG. 23.Example 8: Reaction of Iron Ores with Metallic Sodium in the Presence of Iron Powder

[0556] A reaction between iron ore and metallic sodium was conducted according to step (2) of the present process. In the reactor a crucible was placed with 2 gr of iron oxide mixture (predominantly hematite), 3.8 gr of pure sodium and 1 gr of iron powder. The thermocouple was placed inside the wall of the crucible to control the induction system.

[0557] Before heating the system, nitrogen gas flowed through the system for an hour at a flow rate of 400 mL / min. During the system heating phase the induction system heated the reactor where the crucible was placed, to 400° C., at a heating rate of 15° C. / min and. Nitrogen flow of 100 mL / min was maintained during the experiments. After the system was heated to 400° C. degrees, the system was left at this temperature for two hours. The evaporation phase then began, the nitrogen outlet was closed and the vacuum pump was turned on for an hour. After the evaporation phase, the vacuum pump and heating system were turned off and the system cooled. When the pressure in the system reached 14.6 psi, the nitrogen outlet was opened.

[0558] The product was in powder form. Iron content 38.4% (w % out of sample tested in XRD), metallization—97%. Without wishing to be bound by any theory of mechanism of action, it was found in this experiment that iron powder helps to lower the surface energy of the sodium and enhances wetting and mass transfer.

[0559] The XRD result for this reaction is shown in FIG. 24.Example 9: Reaction of Iron Ores with Metallic Sodium at Different Na:Ore Ratio

[0560] A reaction between iron ore and metallic sodium was conducted according to step (2) of the present process. In the reactor a crucible was placed with 2 gr of iron oxide mixture (predominantly hematite 97% w / w) and 5.7 gr of pure sodium. The thermocouple placed inside the wall of the crucible to control the induction system (ratio of 1:2.85 ore to sodium).

[0561] During the system heating phase the induction system heated the reactor where the crucible was placed, to 400° C., at a heating rate of 10° C. / min and argon flow of 100 mL / min was maintained during the experiments. After the system was heated to 400° C., the system was left at this temperature for two hours. Then the heating system were turned off and the system cooled.

[0562] The product was in powder form. Iron content 38.4% (w % out of sample tested in XRD), metallization—93%. The addition of extra sodium clearly did not have a positive effect on the overall metallization or product purity.

[0563] The XRD result for this reaction is shown in FIG. 25.Example 10: Sodium Oxide Dissociation—Comparative Example

[0564] The process of the present invention was attempted (I) with the sodium oxide dissociation (step (4)) directly following the iron oxide reduction by sodium (step (2)) (Example 10A); and (II) conducting step (3) of separating between the sodium oxide and iron formed in step (2) and then conducting step (4) of sodium oxide dissociation (Example 10B).Example 10A: Sodium Oxide Dissociation without Prior Separation

[0565] An experiment was made in a stainless-steel crucible. Combination of sodium (3.8 gr) and oxide mixture (2 gr ore 1 mostly hematite) was inserted. The crucible was placed in an induction field inside a reactor made of stainless steel 304. The reactor was filled with N2 and the reduction of the oxide was performed at 400° C. for 1 h. Sodium oxide dissociation then was attempted in the same vessel, without separation. The temperature was raised to 800° C. and the pressure was dropped to 1 torr in the reactor for 1 hour.

[0566] FIG. 26 shows considerable production of sodium-ferrites instead of the dissociation of sodium oxide into sodium and oxygen. Conclusions: the XRD analysis shows that considerable amount of the available iron was turned into sodium-ferrites.Example 10B: Sodium Oxide Dissociation with Prior Separation of the Sodium Oxide from the Iron

[0567] Step (2): A reaction between iron ore and metallic sodium was conducted according to step (2) of the present process. In an identical reactor to the one used for Example 10A, sodium (3.7 gr) and iron oxide mixture (2 gr mostly hematite) were mixed and heated to 400° C. for 1 h. the excess sodium was evaporated at 400° C. at 1 torr for 2 h. The reactor was cooled to RT and the sodium oxide and iron were separated using magnets and sieves. The output was separated sodium oxide and iron.

[0568] The XRD result for this reaction is shown in FIG. 27.

[0569] Step (3): A separation between iron and sodium oxide was conducted according to step (3) of the present process. In a nitrogen-filled box with 0% H2O and 1000 ppm of O2 the reaction products of step (2) above (iron, sodium oxide) were placed and separated magnetically.

[0570] FIG. 28 is an XRD of only sodium oxide as extracted from the product.

[0571] Step (4): A sodium oxide dissociation into recycled sodium and oxygen was conducted according to step (4) of the present process. 2 gr of Sodium oxide was extracted from the iron oxide as detailed above and heated to 750° C. for 1 h at 1 torr. The dissociated sodium had evaporated in the reaction due to the high temperature and the low pressure and condensed on the holed ring and alumina heat deflectors (FIG. 30A and FIG. 30B). Total mass collected was 1.2 achieving process mass efficiency of 85% (w / w %). FIG. 29 is a schematic representation of the present system.

[0572] This shows the benefit of the separation of step (3).

[0573] Although the invention is described in conjunction with specific embodiments thereof, it is evident that numerous alternatives, modifications and variations that are apparent to those skilled in the art may exist. It is to be understood that the invention is not necessarily limited in its application to the details of construction and the arrangement of the components and / or methods set forth herein. Other embodiments may be practiced, and an embodiment may be carried out in various ways. Accordingly, the invention embraces all such alternatives, modifications and variations that fall within the scope of the appended claims.

Claims

1. A The process according to claim 26, wherein MT is Fe and the process is for the reduction of an iron metal oxide, the process comprising:(1) providing iron oxide having the formula FenOm, wherein each one of n and m is 1, 2, 3, 4, 5, 6 or 7;(2) contacting the iron oxide with sodium metal in a reactor, adjusting the temperature within the reactor to a first temperature in the range of 100° C. to 500° C., to induce a reaction according to scheme I:(3) separating between the Na2O and the Fe;(4) elevating the temperature of the separated Na2O to a second temperature, which is at least 50° C. higher than the first temperature, to induce a reaction according to scheme II:so that a net reaction, III, resulting from the reactions of schemes I and II, does not consume the sodium metal:

2. The process according to claim 1, wherein step (1) comprises providing an ore which comprises hematite, magnetite, goethite, nacrite, wustite or a combination thereof.

3. The process according to claim 2, wherein the ore further comprises silicon dioxide.

4. The process according to claim 1, wherein the iron oxide is selected from the group consisting of: Fe2O3, Fe3O4, FeOOH and combinations thereof.

5. The process according to claim 4, wherein the iron oxide comprises Fe2O3.

6. The process according to claim 1, wherein the reactor comprises a crucible, wherein step (2) comprises contacting the iron oxide with sodium metal in the crucible.

7. The process according to claim 6, wherein the crucible comprises stainless steel, silicon carbide, copper, aluminum nitride, aluminum oxide, Inconel, ZrO2 or a combination thereof.

8. The process according to claim 6, wherein the crucible comprises aluminum nitride, aluminum oxide, copper, Inconel or a combination thereof.

9. The process according to claim 1, wherein adjusting the temperature within the reactor in step (2) comprises gradually elevating the temperature in the reactor to the first temperature at a rate of 1° C. / minute to 100° C. / minute.

10. The process according to claim 1, wherein elevating the temperature to the second temperature in step (4) comprises gradually elevating the temperature in the reactor to the second temperature at a rate of 1° C. / minute to 100° C. / minute.

11. The process according to claim 1, further comprising step (5) of isolating the sodium metal from the mixture of step (4).

12. The process according to claim 11, wherein the isolation of step (5) entails evaporating the sodium metal from the reactor.

13. The process according to claim 1, further comprising step (6) of condensing the evaporated sodium metal; and step (7) of transferring the condensed sodium metal into the reactor, thereby recycling the sodium metal.

14. The process according to claim 1, comprising:(1) providing the iron oxide;(2) combining the iron oxide with sodium metal in a reactor, adjusting the temperature within the reactor to the first temperature,(3) separating between the Na2O and the Fe;(4) elevating the temperature of the separated Na2O to the second temperature to induce a reaction according to scheme III;(5) evaporating the sodium metal formed in step (4);(6) condensing the evaporated sodium metal; and(7) transferring the condensed sodium metal into the reactor;wherein the process further comprises repeating steps (1)-(3) for at least one additional sequence.

15. The process according to claim 12, wherein evaporating the sodium metal is performed at a temperature in the range of 400° C. to 800° C. and at a pressure in the range of 0.001 Bar to 0.5 Bar.

16. The process according to claim 1, wherein FenOm is Fe2O3, FeO, FeOOH, Fe3O4 or a combination thereof; and reaction schemes I and III are:

17. The process according to claim 1, wherein step (3) comprises mechanically separating between the Na2O and the Fe to produce an isolated iron metal at a purity of at least 90% w / w.

18. The process according to claim 17, wherein step (3) comprises magnetically separating between the Na2O and the Fe.

19. The process according to claim 1, wherein step (4) is performed at a temperature in the range of 400° C. to 800° C.

20. The process according to claim 1, wherein step (4) is performed at a pressure in the range of 0.001 Bar to 0.5 Bar.

21. The process according to claim 1, wherein the reaction mixture of step (2) is substantially devoid of additional solvents and carriers, and consists essentially of the iron metal oxide, the sodium metal and the products reduced iron metal and sodium oxide.

22. The process according to claim 1, wherein step (2) is conducted in an air and water protected environment.

23. The process according to claim 1, wherein step (2) comprises contacting the iron oxide with sodium metal at a weight ratio in the range of 1:20 to 20:1.

24. The process according to claim 1, wherein the reaction mixture of step (4) is substantially devoid of additional solvents and carriers.

25. The process according to claim 1, wherein step (4) is conducted in an air and water protected environment.

26. A process for the reduction of a transition metal oxide, the process comprising:(1) providing at least one transition metal oxide having the formula MTnOm, wherein each one of n and m is 1, 2, 3, 4, 5, 6 or 7, wherein MT is a first-row transition metal selected from: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn;(2) contacting the at least one transition metal with an alkali metal in a reactor, adjusting the temperature within the reactor to a first temperature which is above the melting point of the alkali metal in the range of 100° C. to 500° C., to induce a reaction according to scheme I:wherein MA is Na or K;(3) separating between the MA2O and the MT;(4) elevating the temperature of the separated MA2O to a second temperature, which is at least 50° C. higher than the reduction temperature, to induce a reaction according to scheme II:so that a net reaction, III, resulting from the reactions of schemes I and II does not consume the alkali metal:27-85. (canceled)

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