CN105228955B - Produce the method and its purposes of vanadium boride - Google Patents

Abstract

This document describes the method for producing metal boride by metallic ore and iron slag, the metal boride includes but is not limited to vanadium boride.Also disclose that by the purposes of the method for magnetic iron ore or iron slag original position the generation vanadium boride of titaniferous, and vanadium boride.

Description

Method for producing vanadium boride and use thereof

Background technique

Electrochemical energy represents a reliable energy source and can be used to replace depleted petroleum resources. Metal borides can be used to create batteries or fuel cells, which can be an alternative energy source to petroleum resources. Electrochemical energy storage technologies via the multi-electron oxidation of metal borides, such as vanadium boride, are expected to replace existing batteries based on single-electron charge storage. The multi-electron oxidation of a vanadium boride anode coupled with a carbon-air cathode provides excellent electrochemical energy storage capacity due to its multi-electron charge storage capability. Vanadium can be found in vanadium-containing ores, such as titanium-containing magnetite ores, where the vanadium pentoxide content can range from about 0.63 weight percent to about 1.38 weight percent. Vanadium can also be found in iron slags after smelting, where the vanadium pentoxide content can range from about 6 weight percent to about 25 weight percent. Therefore, it would be desirable to provide a simple method of producing vanadium boride directly from alum-containing ores or slags, and it would also be desirable that the method be operable at ambient temperature and pressure.

Contents of the invention

Embodiments described herein relate to methods of producing metal borides including, but not limited to, vanadium borides. In one embodiment, a method of producing vanadium boride may comprise reducing vanadium pentoxide contained in a vanadium-bearing ore, a vanadium-bearing iron slag, or both to produce vanadium(III) oxide; (III) reduction to vanadium(II) oxide; formation of vanadium nanoparticles; and formation of vanadium boride from the vanadium nanoparticles.

In one embodiment, a method of producing vanadium boride may comprise: reducing vanadium pentoxide contained in a vanadium-containing ore, a vanadium-containing iron slag, or both to produce vanadium nanoparticles; The particles form vanadium boride.

In one embodiment, a method of producing a metal boride may comprise: reducing a metal oxide contained in a metal-containing ore, a metal-containing iron slag, or both to produce metal nanoparticles; Metal borides are formed.

Description of drawings

Figure 1 depicts X-ray diffraction (XRD) of vanadium boride produced from vanadium chloride.

Figure 2 depicts X-ray diffraction (XRD) of vanadium boride produced from vanadium-containing magnetite ore.

Figure 3 depicts X-ray diffraction (XRD) of vanadium borides produced from vanadium-containing iron slags.

Figure 4 depicts the Fourier transform infrared spectrum (FTIR) of vanadium boride produced from vanadium chloride.

Figure 5 depicts the Fourier transform infrared spectrum (FTIR) of vanadium boride produced from vanadium-containing magnetite ore.

Figure 6 depicts the Fourier transform infrared spectrum (FTIR) of vanadium boride produced from vanadium-containing iron slag.

Figure 7 depicts the in situ formation of vanadium boride crystals from vanadium-containing iron slag

Figure 8 depicts various shapes and sizes of vanadium boride crystals produced by the methods described herein.

Figure 9 depicts iron oxide coated vanadium boride crystals.

Detailed description of the invention

Embodiments described herein relate to methods of producing metal borides, including but not limited to vanadium borides, from metal-bearing ores and iron slags. Metal oxides produced by the methods described herein may have a variety of applications including, but not limited to, their use in batteries. In various methods, components can be added in a single batch, in multiple portions, or continuously.

Method for producing vanadium boride (VB ₂ )

In one embodiment, a method of producing vanadium boride may comprise: reducing vanadium pentoxide contained in an alum-containing ore, an alum-containing iron slag, or both to produce vanadium(III) oxide; reduction of vanadium(III) to vanadium(II) oxide; formation of vanadium nanoparticles; and formation of vanadium boride from the vanadium nanoparticles.

In some embodiments, the alum-containing ore can be generally any alum-containing ore, for example, it can be titanium-containing magnetite, oxidized chrysovanite, vanadinite, vanadinite, or combinations thereof. Vanadium is found naturally in many alum-bearing ores as vanadium pentoxide (V ₂ O ₅ ). For example, the amount of vanadium pentoxide in titanium-containing magnetite ore can typically range from about 0.63% to about 1.38% by weight, while the amount of vanadium pentoxide in iron slag after smelting can typically range from about 0.63% to about 1.38% by weight. Calculate from about 6% to about 25%. The ore or slag can generally contain vanadium and vanadium pentoxide in any concentration. In some embodiments, the alum-bearing ore may contain less than about 2% by weight vanadium pentoxide. In some embodiments, the vanadium-containing iron slag may contain less than about 25% by weight vanadium pentoxide.

The reduction of vanadium pentoxide to vanadium(III) oxide can be performed using a catalytic reduction process or a non-catalytic reduction process. In some embodiments, reducing vanadium pentoxide may comprise contacting vanadium pentoxide contained in a vanadium-bearing ore, a vanadium-bearing iron slag, or a mixture or solution of both, with vanadium tetrachloride. Vanadium tetrachloride can be used as a catalyst in catalytic reduction processes.

Vanadium tetrachloride is commercially available or can be prepared by various methods including by combining vanadium pentoxide with hydrochloric acid.

The alum-bearing ore, alum-bearing iron slag, or both may be combined with at least one solvent to form a mixture or solution, which is then contacted with vanadium tetrachloride. Alternatively, the solvent may be added after the vanadium pentoxide is contacted with vanadium tetrachloride. In some embodiments, reducing vanadium pentoxide may further comprise contacting vanadium pentoxide and vanadium tetrachloride with at least one solvent. To prepare the solution, the alum-containing ore, alum-containing iron slag, or both may be ground or otherwise processed into a powder, which is then mixed with at least one solvent before use in the methods described herein. In some embodiments, the finer the alum-bearing ore, alum-bearing iron slag, or both, the more reactive. In some embodiments, the solvent can be water, ethanol, isopropanol, methanol, or combinations thereof. In some embodiments, the solvent may be a mixture of at least two of water, ethanol, isopropanol, and methanol. In some embodiments, the solvent can be a mixture of water and ethanol. In some embodiments, water and ethanol may be present in the mixture in a ratio of about 1 to 2 by volume. For example, a mixture or solution may be formed by pulverizing titanium-containing magnetite ore and mixing with deionized water to produce a 10% by weight titanium-containing magnetite ore solution. In another example, iron slag may be ground into a powder and mixed with deionized water to produce a 10% by weight iron slag solution. Thus, the titanium-containing magnetite ore solution and the ferric slag solution may consist of up to about 25% w/v of titanium-containing magnetite ore and ferric slag, respectively. In some embodiments, the titanium-containing magnetite ore solution and the iron slag solution may consist of about 1 to about 10% titanium-containing magnetite ore and iron slag, respectively. In some embodiments, the titanium-containing magnetite ore solution and the iron slag solution may consist of about 1 to about 25% titanium-containing magnetite ore and iron slag, respectively. In some embodiments, the titanium-containing magnetite ore solution and the iron slag solution may consist of greater than 25% titanium-containing magnetite ore and iron slag, respectively. These ratios, amounts, concentrations, solvents and materials can vary.

In some embodiments, the vanadium-containing ore, the vanadium-containing iron slag, or a mixture or solution of the two in a solvent, and vanadium tetrachloride may generally be contacted in any ratio including, for example, about 2 to 1 ( v/v), to a ratio of about 20 to 1 (v/v). In some embodiments, the solution and vanadium tetrachloride can be mixed in a ratio of about 2 to 1 (v/v), about 5 to 1 (v/v), about 10 to 1 (v/v), about 15 to 1 (v /v), a ratio of about 20 to 1 (v/v), and any ratio between any two of these values.

Reducing the vanadium pentoxide to vanadium(III) oxide may optionally further comprise adding at least one reducing agent after the vanadium pentoxide is contacted with vanadium tetrachloride. The reducing agent can be any compound capable of releasing hydrogen gas ( _H2 ) and providing the boron component of the vanadium boride. In some embodiments, reducing the vanadium pentoxide may further include adding a borohydride compound, a borate compound and hydrogen (H ₂ ) or both after the vanadium pentoxide is contacted with vanadium tetrachloride. In some embodiments, the borohydride compound can be sodium borohydride, lithium borohydride, sodium cyanoborohydride, potassium borohydride, lithium triethylborohydride, or combinations thereof. In some embodiments, the borate compound can be sodium metaborate, sodium borate, lithium metaborate, lithium borate, lithium tetraborate, or combinations thereof.

The reduction of vanadium(III) oxide to vanadium(II) oxide can be performed as a catalytic reduction process or as a non-catalytic reduction process. The catalyst in the catalytic reduction process may be vanadium tetrachloride. Vanadium tetrachloride may come from excess catalyst previously contacted with vanadium pentoxide, or may be introduced additionally. The reduction of vanadium(III) oxide to vanadium(II) oxide may also include contacting the vanadium(III) oxide with at least one reducing agent. The reducing agent can be any compound capable of releasing hydrogen gas ( _H2 ) and providing the boron component of the vanadium boride. In some embodiments, reducing vanadium(III) oxide to vanadium(II) oxide can include contacting vanadium(III) oxide with a borohydride compound, a borate compound, and hydrogen gas (H ₂ ), or both. In some embodiments, the borate compound can be sodium metaborate, sodium borate, lithium metaborate, lithium borate, lithium tetraborate, or combinations thereof. In some embodiments, the borohydride compound can be sodium borohydride, lithium borohydride, sodium cyanoborohydride, potassium borohydride, lithium triethylborohydride, or combinations thereof. In the case where the reducing agent is a borate compound and hydrogen (H ₂ ), the borate compound and hydrogen (H ₂ ) may be additionally introduced, or may be obtained from the excess used in the reduction of vanadium pentoxide to vanadium(III) oxide. The borohydride compound forms a borate compound and hydrogen gas ( _H2 ) in situ. In some embodiments, reducing the vanadium(III) oxide to vanadium(II) oxide may further comprise contacting the vanadium(III) oxide with hydrochloric acid, chlorine gas (Cl ₂ ), or both. Hydrochloric acid and chlorine gas (Cl ₂ ) can be additionally introduced or can be formed in situ from the reduction of vanadium _pentoxide to vanadium(III) oxide. In some embodiments, reducing vanadium(III) oxide to vanadium(II) oxide can include contacting vanadium(III) oxide with sodium metaborate, hydrochloric acid, chlorine (Cl ₂ ), and hydrogen (H ₂ ).

Forming vanadium nanoparticles from vanadium(II) oxide may include contacting the vanadium(II) oxide with at least one reducing agent. The reducing agent can be any compound capable of releasing hydrogen gas ( _H2 ) and providing the boron component of the vanadium boride. In some embodiments, forming vanadium nanoparticles can include contacting vanadium(II) oxide with a borate compound and hydrogen gas ( _H2 ), a borohydride compound, or both. In some embodiments, the borate compound can be sodium metaborate, sodium borate, lithium metaborate, lithium borate, lithium tetraborate, or combinations thereof. In some embodiments, the borohydride compound can be sodium borohydride, lithium borohydride, sodium cyanoborohydride, potassium borohydride, lithium triethylborohydride, or combinations thereof. In the case where the reducing agent is a borate compound and hydrogen (H ₂ ), the borate compound and hydrogen (H ₂ ) may be additionally introduced, or may be obtained from the excess used in the reduction of vanadium pentoxide to vanadium(III) oxide. Borohydride compounds, reduction of vanadium(III) oxide to vanadium(II) oxide or both form borate compounds and hydrogen gas ( _H2 ) in situ. In some embodiments, forming the vanadium nanoparticles can further comprise contacting the vanadium(II) oxide with hydrochloric acid, chlorine gas (Cl ₂ ), or both. Hydrochloric acid and chlorine (Cl ₂ ) can be introduced additionally, or can be formed in situ from vanadium pentoxide to vanadium(III) oxide, vanadium(III) oxide to vanadium( _II ) oxide, or both . In some embodiments, forming vanadium nanoparticles can include contacting vanadium(II) oxide with sodium metaborate, hydrochloric acid, chlorine (Cl ₂ ), and hydrogen (H ₂ ).

In some embodiments, forming vanadium boride from vanadium nanoparticles can include contacting the vanadium nanoparticles with boric acid. In some embodiments, forming the vanadium boride from the vanadium nanoparticles may further comprise exposing the vanadium nanoparticles to hydrogen gas ( _H2 ). In some embodiments, forming vanadium boride from vanadium nanoparticles can include contacting the vanadium boride nanoparticles with boric acid and hydrogen gas ( _H2 ). Boric acid and hydrogen (H ₂ ) can be additionally introduced, or vanadium pentoxide can be reduced to vanadium(III) oxide, vanadium(III) oxide can be reduced to vanadium(II) oxide, vanadium nanoparticles can be formed from vanadium(II) oxide, or The combination forms boronic acid and hydrogen gas ( _H2 ) in situ. Vanadium nanoparticles can bind boron released by boric acid to form vanadium boride in aqueous solution.

In some embodiments, the method of forming vanadium boride can further include forming vanadium boride crystals. In some embodiments, forming vanadium boride crystals can include incubating a solution of vanadium boride at about ambient temperature and pressure. In some embodiments, forming vanadium boride crystals can include incubating a solution of vanadium boride at a temperature above ambient, eg, from about 40°C to about 80°C. In some embodiments, forming vanadium boride crystals may include incubating the vanadium boride at about 40°C to about 50°C, about 50°C to about 60°C, about 60°C to about 70°C, or about 70°C to about 80°C. solution. In some embodiments, forming vanadium boride crystals can include incubating a solution of vanadium boride at about ambient temperature and pressure for a period of time sufficient to form vanadium boride crystals. In some embodiments, forming vanadium boride crystals can include incubating a solution of vanadium boride at a temperature above ambient, eg, about 40°C to about 80°C, for a period of time sufficient to form vanadium boride crystals. The time period can be about 1 hour, about 2 hours, about 4 hours, about 8 hours, about 12 hours, about 24 hours, about 36 hours, about 48 hours, or a range between any two of these values ( including endpoints). In some embodiments, forming vanadium boride crystals may further include mixing or stirring the solution. Vanadium boride crystals may become visible on the surface of the reaction vessel after a period of time, such as about 2 hours, from the start of the reaction. Vanadium boride crystals may also continue to form on the surface of the reaction vessel for a period of time, such as up to about 48 hours, after the reaction has begun.

In some embodiments, the size and shape of the crystals formed can be adjusted by changing the stirring speed, stirring time, concentration of reactants, concentration of solvent, type of solvent used, concentration of reducing agent, reducing agent used type, the ratio of ethanol to water in the reaction, the ratio of vanadium tetrachloride to vanadium-containing magnetite, the ratio of vanadium tetrachloride to vanadium-containing iron slag, the temperature of the reaction, the size of the reaction vessel, the size of the reaction vessel shapes and any combination thereof.

In some embodiments, the method of forming vanadium boride may further include coating the vanadium boride with iron oxide. In some embodiments, the iron oxide can be iron oxide, iron(II) oxide, iron(III) oxide, iron(II, III) oxide, or any combination thereof. Iron oxide can be present in alum-bearing ores and alum-bearing iron slags, which form a coating on the vanadium boride crystals. Iron oxide can also be additionally introduced to coat the vanadium boride. The coating increases the resistance of vanadium boride to corrosion. Figure 9 depicts iron oxide coated vanadium boride crystals produced by the methods described herein.

In some embodiments, the method of producing vanadium boride can be performed at about ambient temperature and pressure. In some embodiments, the method of producing vanadium boride can be performed at above ambient temperature, eg, from about 40°C to about 80°C. In some embodiments, the method of producing vanadium boride can be performed at about 40°C to about 50°C, about 50°C to about 60°C, about 60°C to about 70°C, or about 70°C to about 80°C. In some embodiments, the method can optionally be performed in a single reaction vessel. When the process is carried out in a single reaction vessel, vanadium boride can be formed in situ in a reaction mixture of alum-containing ore, alum-containing iron slag, or both, vanadium tetrachloride, and a reducing agent. Figure 7 depicts the in situ formation of vanadium boride crystals from vanadium-containing iron slag in a single reaction vessel. Panel A shows vanadium boride just after synthesis with hydrogen propelling the material in an upward direction. Panel B shows the continued production of vanadium boride and hydrogen after 30 minutes. Panel C shows continued production of vanadium boride after 60 minutes. Panel D shows the appearance of vanadium boride crystals on the walls of the reaction vessel after about 90 to 120 minutes. Panel E shows the formation of additional vanadium boride crystals and the release of hydrogen gas on the walls of the reaction vessel. Panel F shows the appearance of continued production of vanadium boride crystals after 4 hours of synthesis. Panel G shows the appearance of continued production of vanadium boride crystals after 8 hours of synthesis. Panel H shows the appearance of continued production of vanadium boride crystals after 24 hours of synthesis. At this stage, the vanadium boride crystals can increase significantly in size. Panel I shows the increased vanadium boride crystal size after 36 hours of synthesis. Panel J shows the increased size of vanadium boride crystals after 40 hours of synthesis. Panel K shows the increased size of vanadium boride crystals due to the presence of vanadium oxide (dark green) after 42 hours of synthesis. Panel L shows the increased size of vanadium boride crystals after 44 hours of synthesis. Panel M shows the increased vanadium boride crystal size after 46 hours of synthesis. Panel N shows vanadium boride crystals after the end of synthesis. As shown in panel N, the vanadium boride crystals after the end of the synthesis were transparent and colorless.

During the performance of the method, a change in color of the reaction mixture can be observed by eye or by using an instrument, which can indicate the conversion of vanadium tetrachloride to vanadium pentoxide, vanadium pentoxide to vanadium(III) oxide, and vanadium(III) oxide ) into vanadium(II) oxide. Vanadium(II) oxide can be further reduced to vanadium nanoparticles, which can react with boric acid to form vanadium boride in aqueous solution. Then, by incubating the solution under conditions as described in the disclosed embodiments, crystals of vanadium boride may emerge. The color change can be from red (VCl ₄ ) to yellow (V ₂ O ₅ ), to blue (V ₂ O ₃ ) and to green (VO). After the vanadium nanoparticles are formed, the color of the solution may change to white. Depending on the amount of alum-bearing ore or slag present, the final color can sometimes be gray due to grayish residual material from the ore or slag.

In an alternative embodiment, the method of producing vanadium boride may comprise reducing vanadium pentoxide contained in a vanadium-containing ore, a vanadium-containing iron slag, or both to produce vanadium nanoparticles; The particles form vanadium boride.

Without wishing to be bound by theory, a series of reaction schemes to form vanadium boride are described below. Addition of sodium borohydride can lead to the formation of vanadium(III) oxide according to reaction scheme (I):

V ₂ O ₅ +2VCl ₄ +NaBH ₄ +H ₂ O→V ₂ O ₃ +NaCl ₄ +H ₃ BO ₃ +H ₂ O+Cl ₂ (I)

The reduction of vanadium(III) oxide to vanadium(II) oxide can occur in situ. During Reaction Scheme I, sodium borohydride can decompose into sodium metaborate and hydrogen gas ( _H2 ). Vanadium(III) oxide produced in reaction scheme (I) can be reduced to vanadium(II) oxide according to reaction scheme (II) in the presence of sodium metaborate and hydrogen (H ₂ ):

V ₂ O ₃ +VCl ₄ +NaBO ₂ +4H→VO+NaCl+H ₃ BO ₃ +H ₂ O(II)

Vanadium nanoparticles can be formed in situ according to reaction scheme (III):

2VO+HCl+Cl ₂ +3NaBO ₂ +4H ₂ →V+3NaCl+H ₃ BO ₃ +H ₂ O(III)

Using each of the successive reduction reactions that occur in Reaction Schemes I, II and III, boronic acid can be formed, which can react with vanadium nanoparticles to form vanadium boride according to Reaction Scheme (IV):

V+2H ₃ BO ₃ +3H ₂ →VB ₂ +H ₂ O(IV)

Figures 1 and 4 depict X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), respectively, of vanadium boride produced from vanadium tetrachloride. In Figure 1, all vanadium borides are indicated as _VB2 . In some embodiments, other vanadium borides may also be present, including but not limited to V ₃ B ₂ , VB, V ₅ B ₆ , V ₃ B ₄ , V ₂ B ₃ and VB ₂ . In some embodiments, the type of vanadium boride formed may be determined by the presence of vanadium-containing magnetite ore, vanadium-containing iron slag, or combinations thereof. Figures 2 and 5 depict X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), respectively, of vanadium boride produced from vanadium-containing magnetite ores. Figures 3 and 6 depict X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), respectively, of vanadium borides produced from vanadium-containing iron slags. In Figures 2 and 3, all vanadium borides are denoted as VB ₂ or V ₂ B ₃ . In some embodiments, other vanadium borides may also be present, including but not limited to V ₃ B ₂ , VB, V ₅ B ₆ , V ₃ B ₄ , V ₂ B ₃ and VB ₂ . In some embodiments, the type of vanadium boride formed may be determined by the presence of vanadium-containing magnetite ore, vanadium-containing iron slag, or combinations thereof. X-ray diffraction and Fourier transform infrared spectroscopy (FTIR) were performed, respectively, by standard methods well known to the skilled person using powdered vanadium boride crystals.

Method for producing metal borides (MB _x )

In an alternative embodiment, the method of producing a metal boride may comprise: reducing a metal oxide contained in a metal-containing ore, a metal-containing iron slag, or both to produce metal nanoparticles; and Metal borides are formed. In some embodiments, the metal-bearing ore may be a titanium-containing magnetite ore, oxidized viridite, vanadite, vanadite, or combinations thereof. In some embodiments, the metal oxide can be an oxide of lithium, titanium, magnesium, manganese, aluminum, zinc, iron, or combinations thereof.

The reduction of the metal oxide may be catalytic or non-catalytic reduction of the metal oxide to one or more intermediate metal oxides having a lower metal oxidation state than the metal oxide. For example, in the case of titanium, titanium dioxide _TiO2 is reduced to its intermediate metal oxides, dititanium trioxide _Ti2O3 and titanium monoxide _TiO , which then form titanium nanoparticles. Thus, the metal oxidation state or oxidation state of titanium is reduced from +4 in titanium dioxide to +3 in titanium trioxide and +2 in titanium monoxide. The reduction reaction series can be performed in situ in a single reaction vessel. In some embodiments, reducing the metal oxide can include contacting the metal oxide contained in the metal-bearing ore, the metal-bearing iron slag, or both with the metal chloride. In some embodiments, the metal chloride corresponds to the metal boride formed. For example, when the metal of choice is lithium, the metal chloride is lithium chloride. Metal chlorides can be used as catalysts in catalytic reduction processes.

The metal-bearing ore, the metal-bearing iron slag, or both may be in the form of a mixture or solution prior to contacting the metal chloride. Optionally, solvent may be added after the metal-bearing ore, the metal-bearing iron slag, or both have been contacted with the metal chloride. In some embodiments, reducing the metal oxide can further comprise contacting the metal oxide and the metal chloride with a solvent. To prepare the mixture or solution, the metal-bearing ore, the metal-bearing iron slag, or both may be processed or ground into a powder, then mixed with at least one solvent, and then used in the methods described herein. In some embodiments, the solvent can be water, ethanol, isopropanol, methanol, or combinations thereof. In some embodiments, the solvent may be a mixture comprising at least two of the following: water, ethanol, isopropanol, and methanol. In some embodiments, the solvent can be a mixture of water and ethanol. In some embodiments, water and ethanol may be present in the mixture in a ratio of about 1 to 2 by volume.

Reduction of the metal oxides can occur stepwise to form one or more intermediate metal oxides and then metal nanoparticles. Reducing the metal oxide to one or more intermediate metal oxides may include contacting the metal oxide with at least one reducing agent after contacting the metal oxide with the metal chloride. The reducing agent can be any compound capable of releasing hydrogen gas ( _H2 ) and providing the boron component of the resulting metal boride. In some embodiments, reducing the metal oxide may further include adding a borohydride compound, a borate compound, and hydrogen gas (H ₂ ) or both after contacting the metal oxide with the metal chloride. In some embodiments, the borohydride compound can be sodium borohydride, lithium borohydride, sodium cyanoborohydride, potassium borohydride, lithium triethylborohydride, or combinations thereof. In some embodiments, the borate compound can be sodium metaborate, sodium borate, lithium metaborate, lithium borate, lithium tetraborate, or combinations thereof. Where the reducing agent is a borate compound and hydrogen (H ₂ ), the borate compound and hydrogen (H ₂ ) may additionally be introduced, or may be derived from the The excess borohydride compound forms borate compound and hydrogen gas ( _H2 ) in situ. In some embodiments, reducing the metal oxide to one or more intermediate metal oxides may further comprise contacting the metal oxide with hydrochloric acid, chlorine gas, or both. Hydrochloric acid and chlorine gas (Cl2 ₎ may additionally be introduced, or may be formed in situ from the reduction of the metal _oxide to one or more intermediate oxides. In some embodiments, reducing the metal oxide to one or more intermediate metal oxides may further comprise contacting the metal oxide with sodium metaborate, hydrochloric acid, chlorine (Cl ₂ ), and hydrogen (H ₂ ).

Reducing the intermediate metal oxide to metal nanoparticles can include contacting the intermediate metal oxide with at least one reducing agent. The reducing agent can be any compound capable of releasing hydrogen gas ( _H2 ) and providing the boron component of the resulting metal boride. In some embodiments, reducing the intermediate metal oxide to metal nanoparticles may further comprise contacting the intermediate metal oxide with a borohydride compound, a borate compound and hydrogen gas ( _H2 ), or both. In some embodiments, the borohydride compound can be sodium borohydride, lithium borohydride, sodium cyanoborohydride, potassium borohydride, lithium triethylborohydride, or combinations thereof. In some embodiments, the borate compound can be sodium metaborate, sodium borate, lithium metaborate, lithium borate, lithium tetraborate, or combinations thereof. Where the reducing agent is a borate compound and hydrogen (H ₂ ), the borate compound and hydrogen (H ₂ ) may additionally be introduced, or may be used in the reduction of a metal oxide to one or more intermediate metal oxides The excess borohydride compound forms borate compound and hydrogen gas ( _H2 ) in situ. In some embodiments, reducing the intermediate metal oxide to metal nanoparticles may further comprise contacting the intermediate metal oxide with hydrochloric acid, chlorine gas (Cl ₂ ), or both. Hydrochloric acid and chlorine gas (Cl2 ₎ may additionally be introduced or may be formed in situ from the reduction of the metal _oxide to one or more intermediate metal oxides. In some embodiments, reducing the intermediate metal oxide to metal nanoparticles may further comprise contacting the intermediate metal oxide with sodium metaborate, hydrochloric acid, chlorine (Cl ₂ ), and hydrogen (H ₂ ).

In some embodiments, forming the metal boride from the metal nanoparticles can include contacting the metal nanoparticles with boric acid. In some embodiments, forming the metal boride can further include exposing the metal nanoparticles to hydrogen gas (H ₂ ). In some embodiments, forming the metal boride can include exposing the metal nanoparticles to boric acid and hydrogen ( _H2 ). Boronic acid and _hydrogen ( _H2 ) may additionally be introduced, or may be formed in situ from the reduction of the metal oxide to one or more intermediate metal oxides. Metal nanoparticles can bind boron released from boric acid to form metal borides in aqueous solution.

In some embodiments, the method of forming a metal boride can further include forming metal boride crystals. In some embodiments, forming metal boride crystals can include incubating a solution of metal boride at about ambient temperature and pressure. In some embodiments, forming the metal boride crystals can include incubating the solution of the metal boride at a temperature above ambient, eg, about 40°C to 80°C. In some embodiments, forming metal boride crystals may include incubating the metal boride at about 40°C to about 50°C, about 50°C to about 60°C, about 60°C to about 70°C, or about 70°C to about 80°C. solution. In some embodiments, forming metal boride crystals can include incubating a solution of metal boride at about ambient temperature and pressure for any period of time sufficient to obtain metal boride crystals, such as up to about 24 hours or longer. In some embodiments, forming metal boride crystals may include incubating a solution of metal boride at a temperature above ambient, for example about 40°C to about 80°C, for any period of time sufficient to obtain metal boride crystals, such as up to about 24 hours or longer. In some embodiments, forming the metal boride crystals can include incubating the solution of the metal boride at ambient temperature and pressure for up to about 48 hours. In some embodiments, forming the metal boride crystals can include incubating the solution of the metal boride at a temperature above ambient, eg, about 40°C to 80°C, for up to about 48 hours. In some embodiments, forming metal boride crystals may further include mixing or stirring the solution. Some time after the start of the reaction, such as about 2 hours, metal boride crystals become visible on the surface of the reaction vessel. Metal boride crystals may also continue to form on the surface of the reaction vessel for a period of time, such as up to about 48 hours, after the reaction has begun. In some embodiments, the formation of metal borides results in the formation of transparent colorless crystals.

In some embodiments, the method of forming a metal boride can further include coating the metal boride with iron oxide. Iron oxide may additionally be incorporated to coat the metal borides. Coatings increase the resistance of metal borides to corrosion. Iron oxide may be present in titanium-containing magnetite ore, oxidized chrysanthemite, vanadinite, vanadylite, iron slag, or combinations thereof as a feedstock in the methods described herein. Iron oxide may additionally be incorporated to coat the metal borides.

In some embodiments, methods of producing metal borides can be performed at about ambient temperature and pressure. In some embodiments, the method of producing metal borides can be performed at above ambient temperature, for example, from about 40°C to about 80°C. In some embodiments, the method of producing metal borides can be performed at above ambient temperature, for example, from about 40°C to about 50°C, from about 50°C to about 60°C, from about 60°C to about 70°C, or from about 70°C to about 80°C, proceed. In some embodiments, methods of producing metal borides can be performed in a single reaction vessel.

Metal borides, including but not limited to vanadium borides, can be produced using the methods described herein at significantly lower cost than currently practiced commercial production methods. For example, the cost of producing vanadium boride by the methods disclosed herein can be as much as one hundred times less expensive than currently practiced commercial manufacturing methods.

Vanadium borides produced by the methods disclosed herein may possess physical characteristics including, but not limited to, hardness, electrical conductivity, high melting point, and ability to decompose in strong oxidizing or alkaline agents. In some embodiments, the hardness of the vanadium boride is determined by a hammer process. In some embodiments, vanadium borides produced from magnetite ore or iron slag are at least two times harder than vanadium borides produced from vanadium tetrachloride.

Vanadium boride produced by the methods disclosed herein can have a variety of applications including, but not limited to, automotive batteries with improved storage and discharge potential, any application that uses electrical energy or can be used, and as a lithium battery in conventional fuel cells and batteries. and zinc electrode substitutes.

Vanadium boride produced by the methods disclosed herein may be suitable for use in vanadium boride air batteries. Vanadium boride produced by the methods disclosed herein can have high energy storage capacity when used in such batteries. The energy storage capacity can be equal to or greater than that of gasoline, lithium-ion or zinc-air batteries.

Vanadium boride produced by the methods disclosed herein can be used as an anode in batteries. Vanadium borides produced by the methods disclosed herein can also be used as anodes in rechargeable batteries. Such rechargeable batteries may have fast recharge speeds and greater energy storage capacity than lithium-ion batteries. In non-rechargeable batteries, vanadium boride produced by the methods disclosed herein can impart superior charge storage density.

Example

Example 1 - Preparation of Titanium-Containing Magnetite Ore for the Preparation of Vanadium Boride

5 g of titanium-containing magnetite ore was ground into powder and mixed with 50 ml of deionized water to produce a 10% titanium-containing magnetite ore solution.

Embodiment 2-preparation of iron slag for the preparation of vanadium boride

5 g of iron slag was pulverized and mixed with 50 ml of deionized water to produce a 10% iron slag ore solution.

Example 3 - Preparation of vanadium tetrachloride for the preparation of vanadium boride

Vanadium tetrachloride was freshly prepared from 1M vanadium pentoxide dissolved in concentrated hydrochloric acid (11.65M). Vanadium pentoxide is combined with hydrochloric acid in a ratio of 1:10 by volume.

Example 4 - Preparation of vanadium tetrachloride for the preparation of vanadium boride

Vanadium tetrachloride was freshly prepared by combining 0.182 g of vanadium pentoxide with 4 ml of concentrated hydrochloric acid (11.65 M), followed by mixing and incubating at ambient temperature and pressure for 10 minutes.

Example 5 - In situ preparation of vanadium boride from titanium-containing magnetite ore

10 ml of the titanium-containing magnetite solution from Example 1 was mixed with 30 ml of a 2:1 (v/v) mixture of ethanol and water in a reaction vessel under ambient temperature and pressure conditions. 1 ml of freshly prepared vanadium tetrachloride from Example 3 or 4 was added to the titanium-containing magnetite solution and mixture of ethanol and water. The addition of vanadium tetrachloride results in the separation of vanadium pentoxide from the titanium-containing magnetite ore. After the titanium-containing magnetite ore was combined with vanadium tetrachloride, 25 ml of 1M sodium borohydride was added to the reaction vessel to produce vanadium(III) oxide according to the following reaction scheme:

V ₂ O ₅ +2VCl ₄ +NaBH ₄ +H ₂ O→V ₂ O ₃ +NaCl ₄ +H ₃ BO ₃ +H ₂ O+Cl ₂

In the above reaction scheme, sodium borohydride decomposes into sodium metaborate and hydrogen gas ( _H2 ). In the presence of sodium metaborate and hydrogen (H ₂ ), vanadium(III) oxide is reduced to vanadium(II) oxide according to the following reaction scheme:

V ₂ O ₃ +VCl ₄ +NaBO ₂ +4H ₂ →VO+NaCl+H ₃ BO ₃ +H ₂ O

Vanadium nanoparticles were formed in situ from vanadium(II) oxide according to the following reaction scheme:

2VO+HCl+Cl ₂ +3NaBO ₂ +4H ₂ →V+3NaCl+H ₃ BO ₃ +H ₂ O

Using each of the successive reduction reactions shown above, boric acid is formed, which reacts with vanadium nanoparticles to form vanadium boride according to the following scheme:

V+2H ₃ BO ₃ +3H ₂ →VB ₂ +H ₂ O

The reaction mixture was incubated at ambient temperature and pressure for about 48 hours, resulting in the formation of vanadium boride crystals. The reaction mixture was continuously stirred during the incubation and addition of reactants.

As vanadium boride crystals form in situ, they are coated with iron oxide derived from a titanium-containing magnetite solution.

Example 6 - In situ preparation of vanadium boride by iron slag

10 ml of the iron slag solution from Example 1 was mixed with 30 ml of a 2:1 (v/v) mixture of ethanol and water in a reaction vessel under ambient temperature and pressure conditions. 1 ml of freshly prepared vanadium tetrachloride from Example 3 or 4 was added to the iron slag solution and the mixture of ethanol and water. The addition of vanadium tetrachloride resulted in the separation of vanadium pentoxide from the iron slag. After the magnetite ore was combined with vanadium tetrachloride, 25 ml of 1M sodium borohydride was added to the reaction vessel to produce vanadium(III) oxide according to the following reaction scheme:

V ₂ O ₅ +2VCl ₄ +NaBH ₄ +H ₂ O→V ₂ O ₃ +NaCl ₄ +H ₃ BO ₃ +H ₂ O+Cl ₂

In the above reaction scheme, sodium borohydride decomposes into sodium metaborate and hydrogen gas ( _H2 ). In the presence of sodium metaborate and hydrogen (H ₂ ), vanadium(III) oxide is reduced to vanadium(II) oxide according to the following reaction scheme;

V ₂ O ₃ +VCl ₄ +NaBO ₂ +4H→VO+NaCl+H ₃ BO ₃ +H ₂ O

Vanadium nanoparticles were formed in situ from vanadium(II) oxide according to the following reaction scheme:

2VO+HCl+Cl ₂ +3NaBO ₂ +4H ₂ →V+3NaCl+H ₃ BO ₃ +H ₂ O

Using each of the successive reduction reactions shown above, boric acid is formed, which reacts with vanadium nanoparticles to form vanadium boride according to the following scheme:

V+2H ₃ BO ₃ +3H ₂ →VB ₂ +H ₂ O

The reaction mixture was incubated at ambient temperature and pressure for about 48 hours, resulting in the formation of vanadium boride crystals. The reaction mixture was continuously stirred during the incubation and addition of reactants.

As vanadium boride crystals form in situ, they are coated with iron oxide derived from iron slag.

Example 7 - Preparation of vanadium boride from magnetite ore

10 ml of the titanium-containing magnetite solution from Example 1 was mixed with 30 ml of a 2:1 (v/v) mixture of ethanol and water in a reaction vessel under ambient temperature and pressure conditions. 1 ml of freshly prepared vanadium tetrachloride from Example 3 or 4 was added to the titanium-containing magnetite solution and mixture of ethanol and water. The addition of vanadium tetrachloride resulted in the separation of vanadium pentoxide from the magnetite ore. After the ore was combined with vanadium tetrachloride, 25 ml of 1M sodium borohydride was added to the reaction vessel to produce vanadium(III) oxide.

Then, 1M sodium metaborate and excess hydrogen ( _H2 ) were added to the reaction vessel under ambient temperature and pressure conditions to produce vanadium(II) oxide. Then, fresh sodium metaborate was added in excess to generate vanadium nanoparticles.

Then, 1M boric acid was added to the reaction vessel to generate vanadium boride. The reaction mixture was incubated at ambient temperature and pressure for about 48 hours, resulting in the formation of vanadium boride crystals. The reaction mixture was continuously stirred during incubation and addition of reactants.

Example 8 - Preparation of vanadium boride from iron slag

10 ml of the iron slag solution from Example 1 was mixed with 30 ml of a 2:1 (v/v) mixture of ethanol and water in a reaction vessel under ambient temperature and pressure conditions. 1 ml of freshly prepared vanadium tetrachloride from example 3 or 4 was added to the iron slag solution and the mixture of ethanol and water. The addition of vanadium tetrachloride resulted in the separation of vanadium pentoxide from the iron slag. After the step of combining the slag with vanadium tetrachloride, 25 ml of 1M sodium borohydride was added to the reaction vessel to produce vanadium(III) oxide. Then, 1 M sodium metaborate and hydrogen gas (H ₂ ) were added to the reaction vessel in excess under ambient temperature and pressure conditions to produce vanadium(II) oxide. Then, fresh sodium metaborate was added in excess to generate vanadium nanoparticles.

Then, 1M boric acid was added to the reaction vessel to generate vanadium boride. The reaction mixture was incubated at ambient temperature and pressure for about 48 hours, resulting in the formation of vanadium boride crystals. The reaction mixture was continuously stirred during the incubation and addition of reactants.

Example 9 - Color Change as Preparation of Vanadium Borides from Borides from Titanium-Containing Magnetite Ore or Iron Slag indication of progress

Addition of sodium borohydride to the reaction results in a color change of the reaction mixture of titanium-containing magnetite ore or iron slag and vanadium tetrachloride. The color gradually changes from red (due to VCl ₄ ) to yellow (due to V ₂ O ₅ ), to blue (due to V ₂ O ₃ ) and to green (due to VO). After the incubation period at ambient temperature and pressure conditions, a large amount of gas was released from the reaction mixture and the color of the reaction mixture changed from green to white. The gas produced is hydrogen, chlorine or a combination of both. After the color of the reaction mixture changed to white, the color changed again in rapid succession from white to black, to green and then to gray. The color of the reaction mixture changed to gray indicating the end of the reaction and the formation of vanadium(III) oxide.

Incubation results in the formation of vanadium boride. First, depending on the concentration of reactants, the color of the solution will appear green/gray/cyanine. After 2-3 hours of incubation, vanadium boride crystals began to appear on the surface of the reaction vial. Once crystals start to appear, they grow in size and individual crystals come together to form larger numbers of crystals.

Example 10 - Preparation of Vanadium Boride Microparticles and Nanoparticles

The particle size of the vanadium boride crystals formed in any one of Examples 5 to 8 is affected by the stirring time and speed of the vanadium boride during and after its formation. Due to the prolonged stirring time during and after the synthesis, micro- and nanoparticles of vanadium boride can be synthesized.

Example 11 - Preparation of vanadium boride nanoparticles

Vanadium boride was prepared by any one of Examples 5-8. Vanadium boride nanoparticles were produced by ball milling in a tungsten carbide vessel using a tungsten carbide bearing with a diameter of 10 mm under an argon atmosphere. The container was then sealed and placed in a RetschPM 100 ball mill. The vanadium boride was ground continuously at 600 rpm for 4 hours. After milling, the temperature of the container was returned to ambient temperature and the vanadium boride nanoparticles were collected under an argon atmosphere.

Example 12 - Isolation and Purification of Vanadium Boride

By decanting and washing, the vanadium boride produced by any one of Examples 5 to 8 can be separated from the residual magnetite ore and iron slag precipitated at the bottom of the reaction vessel during the production of vanadium boride from magnetite ore or iron slag , titanium dioxide, iron oxide, aluminum oxide or other metal oxides, because vanadium boride is insoluble in water and ethanol.

For example, in any of Examples 5 to 8, after formation of vanadium boride, impurities such as sodium chloride and boric acid were dissolved in the ethanol water mixture. Such impurities can be separated by decantation and washing.

Pure vanadium boride is obtained after a series of washing and decanting steps. The resulting vanadium boride can be coated with iron oxide also present in the reaction vessel.

Example 13 - Preparation of vanadium boride battery

Vanadium boride from the magnetite ore or iron slag of any of Examples 5 to 8 can be used as an anode in a rechargeable battery. A rechargeable battery consists of two half-cells, an anode and an air cathode. Vanadium boride mixed with carbon and potassium hydroxide to form an anode comprising from about 50% to about 80% vanadium boride and from about 20% to about 50% carbon optimized for multi-electron oxidation via vanadium boride discharge. The electrolyte was potassium hydroxide in water (5M), as it is a suitable ion conductor material. A membrane is also provided to act as a separator to minimize any non-electrochemical interactions between the anode and air cathode. Vanadium boride undergoes an oxidation of 11 electrons/molecule, which includes the oxidation of each of the tetravalent transition metal ion V (+4→+5) and the two borons 2xB (-2→+3). The discharge potential of a high capacity battery is expected to be about 1.34 volts (V), while the theoretical discharge potential is about 1.55 volts (V). The inherent storage capacity of the battery is expected to be approximately 1.55 Volts (V) x 20,700 Ah/L = 32,000 Watt-hours/liter (Wh/L). The anode has an open circuit potential of about 1.34 volts. At the anode, hydrogen is oxidized according to the following reaction: VB ₂ +11OH → ¹ /2V ₂ O ₅ +B ₂ O ₃ +11/2 H ₂ O+11e-, producing water and releasing _two electrons. Electrons flow through the external circuit and return to the cathode, reducing oxygen in the reaction, producing hydroxide ions: _O2 + 2H2O ₊ 4e- = 11OH, where the net reaction consumes one oxygen atom and two hydrogen atoms. Electricity and heat are formed as by-products of this reaction.

Example 14 - Preparation of vanadium boride battery

Vanadium boride derived from the titanium-containing magnetite ore or iron slag produced by either of Examples 5 and 7 can be dissolved in 2M potassium hydroxide solution to produce the anode, and the anode is added to the first half-cell of the cell . A battery may comprise two half-cells that are in electrochemical contact with each other through an electrolyte (potassium hydroxide). Potassium hydroxide can be used as an electrolyte in vanadium boride batteries because of its superior ionic conductivity. The first half-cell may include a vanadium boride anode and the second half-cell includes a carbon-air cathode. The anode, electrolyte, and carbon air cathode and separator arranged to minimize any non-electrochemical interaction between the anode and the air cathode can be sealed within the battery cell. The discharge of the anode occurs via multi-electron oxidation of vanadium boride. The battery can generate a continuous 1.34-volt open circuit discharge.

Example 15 - Preparation of vanadium boride battery

As in Examples 6 or 8, vanadium boride derived from iron slag was dissolved in 2M potassium hydroxide solution to create an anode, and the anode was added to the first half-cell of the cell. A battery may comprise two half-cells that are in electrochemical contact with each other through an electrolyte (potassium hydroxide). Potassium hydroxide can be used as an electrolyte in vanadium boride batteries because of its superior ionic conductivity. The first half-cell may include a vanadium boride anode and the second half-cell may include a carbon-air cathode. The anode, electrolyte and carbon air cathode and separator arranged to minimize any non-electrochemical interaction between the anode and the air cathode may be sealed within the battery cell. Discharge from the anode can occur via multi-electron oxidation of vanadium boride. The battery can sustain a 1.34-volt open circuit discharge.

Example 16 - Preparation of vanadium boride-air button cell

A zinc-air button cell with a 1 cm anode surface area can be used to create a vanadium boride-air button cell. 0.1 g of ground vanadium boride from the magnetite ore produced in Examples 5 or 7 can be mixed with activated carbon in a 1:1 ratio in a porcelain crucible and 5M potassium hydroxide solution can be added to produce Slurry of zinc anode in 1 cm diameter zinc-air button cell. Batteries can be discharged with a constant resistive load and exhibit a higher potential. 5M potassium hydroxide solution was used as electrolyte. The loading of anode material for each cell may be 10 mAh. To prepare the vanadium boride-air button cell, the zinc-air button cell is carefully opened and the zinc anode and carbon cathode materials are removed. The vanadium boride slurry can then be added at the zinc anode. A separator can then be placed over the vanadium boride anode. Activated carbon slurry can be prepared using 5M potassium hydroxide to produce activated carbon slurry. The activated carbon slurry replaces the initial carbon cathode in the lid of the button cell. A lid can then be placed on the separator over the anode, resulting in a hermetic seal.

Example 17 - Preparation of vanadium boride-air button cell

A zinc-air button cell with a 1 cm anode surface area can be used to create a vanadium boride-air button cell. 0.1 g of ground vanadium boride from the iron slag produced in Example 6 or 8 can be mixed with activated carbon in a 1:1 ratio in a porcelain crucible and 5M potassium hydroxide solution can be added to produce Slurry of zinc anode in a conventional 1 cm diameter zinc-air button cell. Batteries can be discharged with a constant resistive load and exhibit a higher potential. 5M potassium hydroxide solution can be used as electrolyte. The loading of anode material for each cell may be 10 mAh. To prepare the vanadium boride-air button cell, the zinc-air button cell can be opened and the zinc anode and carbon cathode materials removed. A vanadium boride slurry is then added in place of the zinc anode. A separator is then placed over the vanadium boride anode. Activated carbon slurry can be prepared using 5M potassium hydroxide to produce activated carbon slurry. Then, the activated carbon slurry replaces the initial carbon cathode in the coin cell lid. The lid is then placed on the separator above the anode, resulting in a hermetic seal.

Example 18 - Preparation of Vanadium Boride-Air Watch Battery

A 20.0 mm x 3.2 mm CR2032 watch cell with a lithium anode was used to prepare the cells. Open the cell and remove the lithium anode. Carbon cathode material is also removed. To create the anode, 0.5 g of ground vanadium boride from the magnetite ore produced in Example 5 or 7 was mixed with activated carbon powder in a 1:1 ratio in a porcelain crucible, followed by the addition of 5M potassium hydroxide solution to prepare the vanadium boride pulp. Then, a vanadium boride slurry is added at the lithium anode. Then, a separator is placed over the vanadium boride anode. Activated carbon slurries were prepared using 5M potassium hydroxide to create carbon air cathodes. The carbon air cathode is mounted on the cell and the cell is tightly closed.

Example 19 - Preparation of Vanadium Boride-Air Watch Battery

A 20.0 mm x 3.2 mm CR2032 watch cell with a lithium anode was used to prepare the cell. Open the cell and remove the lithium anode. Carbon cathode material is also removed. To create the anode, 0.5 g of ground vanadium boride from the iron slag produced in Example 6 or 8 was mixed with activated carbon powder in a 1:1 ratio in a porcelain crucible, followed by the addition of 5M potassium hydroxide solution to prepare the boride Vanadium slurry. Then, a vanadium boride slurry is added at the lithium anode. Then, a separator is placed over the vanadium boride anode. Activated carbon slurries were prepared using 5M potassium hydroxide to create carbon air cathodes. The carbon air cathode is mounted on the cell and the cell is tightly closed.

Example 20 - Preparation of vanadium boride-air coin cell

A 5 cm coin cell with a lithium anode can be used to prepare the battery. 2 g of ground vanadium boride from the magnetite ore produced in Example 5 or 7 was mixed with activated carbon powder (25%) in a porcelain crucible, followed by addition of 5M potassium hydroxide solution to prepare a vanadium boride anode slurry. Then, a vanadium boride slurry is added at the lithium anode. Then, a separator is placed over the vanadium boride anode. Activated carbon slurries were prepared using 5M potassium hydroxide to create carbon air cathodes. The carbon air cathode is mounted on the cell and the cell is tightly closed.

Example 21 - Preparation of vanadium boride-air coin cell

A 5 cm coin cell with a lithium anode can be used to prepare the battery. 2 g of ground vanadium boride from the iron slag produced in Example 6 or 8 was mixed with activated carbon powder (25%) in a porcelain crucible, followed by addition of 5M potassium hydroxide solution to prepare a vanadium boride anode slurry. Then, a vanadium boride slurry is added in place of the lithium anode. Then, a separator is placed over the vanadium boride anode. Activated carbon slurries were prepared using 5M potassium hydroxide to create carbon air cathodes. The carbon air cathode is mounted on the cell and the cell is tightly closed.

Example 22 - Comparison of vanadium boride batteries produced from various sources

Vanadium boride can be obtained from vanadium chloride, magnetite ore as in Examples 5 and 7, or from iron slag as in Examples 6 and 8. Using vanadium boride from each source, vanadium boride batteries can be prepared as follows. Vanadium boride was dissolved in 2M potassium hydroxide solution to create a vanadium boride anode. Then, the anode is placed in the first half-cell of the battery. The battery consists of two half-cells which are in electrochemical contact with each other via an electrolyte (potassium hydroxide). Potassium hydroxide is used for its superior ionic conductivity. The first half-cell includes a vanadium boride anode and the second half-cell includes a carbon cathode.

A first half cell, a second half cell, and an electrolyte are combined in a battery cell, and a separator is placed between the first half cell and the second half cell. The battery cells are then sealed.

Discharge of the anode (first half-cell) occurs via multi-electron oxidation of vanadium boride. The battery can sustain a 1.34-volt open circuit discharge.

Batteries using vanadium boride prepared from magnetite and iron slag can have a constant discharge over a longer duration than batteries prepared only with vanadium boride from vanadium chloride. The increased discharge duration of cells prepared using vanadium boride may be due to the iron oxide coating, which enables vanadium boride prepared from magnetite or iron slag to be prepared from magnetite or iron slag.

Example 23 - Regeneration of vanadium boride after use

Regeneration of electrochemically irreversible basic vanadium borides from fuel cell discharge products can be achieved by treatment with magnesium. Specifically, the dried vanadate and borate products were combined with magnesium and ball milled at room temperature for about 24 hours under an argon atmosphere. Included impurities (eg, magnesium oxide and residual reactants) were removed by leaching the milled powder with a 10% hydrochloric acid solution for about 1 hour. Then, after leaching, the solution was decanted and the solid product was washed with deionized water and dried under vacuum.

Example 24 - Regeneration of vanadium boride after use

Regeneration of electrochemically irreversible basic vanadium borides from fuel cell discharge products can be achieved by treatment with heated hydrogen gas. Specifically, the dried vanadate and borate products were combined with magnesium and ball milled at room temperature for about 24 hours under an argon atmosphere. Heated hydrogen is then passed over the vanadate and borate and reduced to the starting materials for reintroduction into the fueled cell. The recharging process is carried out above 100° C. to eliminate the water formed from the hydrogen as steam.

The present disclosure is not to be limited by the particular embodiments described in this application, which are intended as illustrations in various respects. It will be apparent to those skilled in the art that various modifications and changes can be made without departing from the spirit and scope thereof. Functionally equivalent methods and apparatuses within the scope of the present disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing description. It is intended that such improvements and modifications come within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that this disclosure is not limited to particular methods, reagents, compounds, compositions or biological systems, which can, 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.

Although various compositions, methods and devices are described in terms of "comprising" (interpreted as "including but not limited to") various components or steps, the compositions, methods and devices can also be "consisting essentially of various components and steps" or "consisting of various components and steps", such terms should be understood as defining a substantially closed group.

With respect to the use of substantially any plural and/or singular term herein, those skilled in the art will be able to convert from the plural to the singular and/or from the singular to the plural as appropriate depending on the context and/or application. For purposes of clarity, each singular/plural permutation is explicitly set forth herein.

It will be understood by those skilled in the art that terms used herein and in particular in the appended claims (e.g., the body of the appended claims) are generally intended to be "open-ended" terms (e.g., the term "comprising" should be construed For "including but not limited to", the term "having" should be interpreted as "having at least", the term "comprising" should be interpreted as "including but not limited to", etc.). It will be further understood by those within the art that if a specific number of a claim recitation is intended to be introduced, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, even when the same claim contains the introductory phrase "one or more" or "at least one" and an indefinite article such as "a", "an" or "the", use of such phrase should not be construed as It is implied that a claim recitation introduced by the indefinite articles "a," "an," or "the" limits any particular claim containing such an introduced claim recitation to only one embodiment of such recitation ( For example, "a" and/or "an" and/or "the" should be construed to mean "at least one" or "one or more"); the same applies to definite articles that introduce items listed in claims usage of. In addition, even if a specific number of an introduced claim recitation is expressly recited, those skilled in the art will recognize that such a recitation is to be interpreted to mean at least that recited number (eg, a mere recitation "two" without other modifiers) A list item" means at least two list items, or more than two list items). Furthermore, in those cases where an idiom similar to "at least one of A, B, C, etc." is used, usually such sentence-making means the idiom as would be understood by those skilled in the art (e.g., "has A, B, etc. and at least one of C" shall include, but not be limited to, having A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C and so on system). In those cases where an idiom similar to "at least one of A, B, or C, etc." is used, usually such sentence-making means the idiom as would be understood by those skilled in the art (e.g., "has A, B, or C etc. A system" shall include, but is not limited to having A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B and C together etc. system). Those skilled in the art should further understand that any transitional words and/or phrases that actually present two or more alternative terms, no matter in the description, claims or drawings, should be understood as including one of the terms, the term Possibility of either or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."

Furthermore, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is thereby also in terms of any individual member or subgroup of members of the Markush group. describe.

As will be understood by those skilled in the art, for any and all purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range may readily be considered sufficiently descriptive and to enable the same range to be readily broken down into at least two, three, four, five, ten, etc. equal parts. As a non-limiting example, each range discussed herein can be easily broken down into a lower third, a middle third, an upper third, and so on. As will also be understood by those skilled in the art, all language such as "up to," "at least," etc. includes the recited numeral and refers to ranges that may then be broken down into sub-ranges as described above. Finally, as will be understood by those skilled in the art, a range includes each individual member. Thus, for example, a group with 1-3 substitutes refers to a group with 1, 2 or 3 substitutes. Similarly, a group with 1-5 substitutions refers to groups with 1, 2, 3, 4 or 5 substitutions, and so on.

Claims (42)

1. producing the method for vanadium boride, methods described includes：

Ore, the iron slag of aluminiferous or the vanadic anhydride included in the two of aluminiferous are reduced, to produce vanadium oxide (III)；

The vanadium oxide (III) is reduced into vanadium oxide (II)；

Vanadium nano particle is formed by vanadium oxide (II)；With

Vanadium boride is formed by the vanadium nano particle,

Wherein methods described is carried out in environment temperature or in 40 DEG C to 80 DEG C of temperature,

The vanadium oxide (III) is reduced into vanadium oxide (II) includes making the vanadium oxide (III) contact hydroboration materialization Compound, borate compound and hydrogen (H₂) or the two；Or, wherein making the vanadium oxide (III) be reduced into vanadium oxide (II) Including making the vanadium oxide (III) contact kodalk, hydrochloric acid, chlorine (Cl₂) and hydrogen (H₂)；

Wherein forming the vanadium nano particle includes making the vanadium oxide (II) contact borohydride compound, borate compound With hydrogen (H₂) or the two；Or, wherein formed the vanadium nano particle include make the vanadium oxide (II) contact kodalk, Hydrochloric acid, chlorine (Cl₂) and hydrogen (H₂)；

Wherein forming the vanadium boride by the vanadium nano particle includes making the vanadium nano particle contact boric acid；Or, wherein Forming the vanadium boride by the vanadium nano particle includes making vanadium boride nano particle contact boric acid and hydrogen (H₂)。

2. the method described in claim 1, wherein the ore of the aluminiferous be the magnetic iron ore of titaniferous, the patronite of oxidation, Vanadinite, carnotite or its combination.

3. the method described in claim 1, wherein the ore of the aluminiferous includes the vanadic anhydride for being less than 2% by weight.

4. the method described in claim 1, wherein the iron slag of the aluminiferous includes being less than 25% five oxidations two by weight Vanadium.

5. the method described in claim 1, wherein reducing the vanadic anhydride includes making ore, the iron slag of aluminiferous of aluminiferous Or the vanadic anhydride contact vanadium tetrachloride included in the two.

6. the method described in claim 5, further comprises making the vanadic anhydride wherein reducing the vanadic anhydride Contact after vanadium tetrachloride, add borohydride compound, borate compound and hydrogen (H₂) or the two.

7. the method described in claim 1 or 6, wherein the borohydride compound is sodium borohydride, lithium borohydride, cyano group boron Sodium hydride, potassium borohydride and lithium triethylborohydride or its combination.

8. the method described in claim 1 or 6, wherein the borate compound be kodalk, Boratex, lithium metaborate, Lithium borate, lithium tetraborate or its combination.

9. the method described in claim 5, further comprises making vanadic anhydride and tetrachloro wherein reducing the vanadic anhydride Change vanadium contact solvent.

10. the iron slag of the ore of the method described in claim 9, wherein aluminiferous, aluminiferous or the two solution in a solvent and Vanadium tetrachloride is contacted with by volume 2 to 1 to 20 to 1 ratio.

11. the method described in claim 10, wherein the solvent is water, ethanol, isopropanol, methanol or its combination.

12. the method described in claim 10, wherein the solvent is the mixture of water and ethanol.

13. the method described in claim 12, wherein the water and ethanol are deposited with the ratio of by volume 1 to 2 water and ethanol .

14. the method described in claim 1, wherein described make the vanadium oxide (III) contact borohydride compound, borate Compound and hydrogen (H₂) or the two the step of further comprise making the vanadium oxide (III) to contact hydrochloric acid, chlorine (Cl₂) or two Person.

15. the method described in claim 1, wherein described make the vanadium oxide (II) contact borohydride compound, borate Compound and hydrogen (H₂) or the two the step of further comprise making the vanadium oxide (II) to contact hydrochloric acid, chlorine (Cl₂) or two Person.

16. the method described in claim 1, wherein described further comprise making the step of make the vanadium nano particle contact boric acid The vanadium nano particle contact hydrogen (H₂)。

17. the method described in claim 1, further comprises forming vanadium boride crystal.

18. the method described in claim 17, wherein being formed, the vanadium boride crystal is included in environment temperature and pressure is incubated institute State the solution of vanadium boride.

19. the method described in claim 17, wherein being formed, the vanadium boride crystal is included in environment temperature and pressure is incubated institute State the solution of vanadium boride up to 24 hours to 48 hours.

20. the method described in claim 18, further comprises stirring the solution wherein forming the vanadium boride crystal.

21. the method described in claim 1, further comprises using vanadium boride described in iron oxide-coated.

22. the method described in claim 1, wherein methods described are carried out in environment temperature and pressure.

23. the method described in claim 1, wherein methods described are carried out in single reaction container.

24. producing the method for metal boride, methods described includes：

Ore of the reduction containing metal, the metal oxide included containing the iron slag of metal or in the two, to produce metal nano Grain；With

Metal boride is formed by the metal nanoparticle,

Wherein methods described is carried out in environment temperature or in 40 DEG C to 80 DEG C of temperature,

Wherein reducing the metal oxide includes making the ore containing metal, the metal included containing the iron slag of metal or in the two Oxide interface metal chloride；After metal oxide contacting metal chloride is made, addition borohydride compound, boric acid Salt compound and hydrogen (H₂) or the two, to form the one kind of metal oxidation state less than the metal oxidation state of the metal oxide Or a variety of intermediate metal oxides；And make one or more intermediate metal oxide contact borohydride compounds, boron Phosphate compounds and hydrogen or the two；Or make one or more intermediate metal oxide contact kodalks, hydrochloric acid, chlorine Gas (Cl₂) and hydrogen (H₂)；

Wherein forming metal boride includes making the metal nanoparticle contact boric acid；Or wherein form metal boride bag Including makes the metal nanoparticle contact boric acid and hydrogen (H₂)。

25. the method described in claim 24, wherein the ore containing metal is the magnetic iron ore of titaniferous, the green sulphur vanadium of oxidation Ore deposit, vanadinite, carnotite or its combination.

26. the method described in claim 24, wherein the metal oxide is lithium, titanium, magnesium, manganese, aluminium, zinc, iron or its combination Oxide.

27. the method described in claim 24, wherein the metal boride that the metal chloride is correspondingly formed.

28. the method described in claim 24, wherein the borohydride compound is sodium borohydride, lithium borohydride, cyano group boron Sodium hydride, potassium borohydride, lithium triethylborohydride or its combination.

29. the method described in claim 24, wherein the borate compound is kodalk, Boratex, lithium metaborate, boron Sour lithium, lithium tetraborate or its combination.

30. the method described in claim 24, further comprises making metal oxide and gold wherein reducing the metal oxide Belong to chloride contact solvent.

31. the method described in claim 30, wherein the solvent is water, ethanol, isopropanol, methanol or its combination.

32. the method described in claim 30, wherein the solvent is the mixture of water and ethanol.

33. the method described in claim 32, wherein the water and ethanol exist with by volume 1 to 2 ratio.

34. the method described in claim 24, wherein making one or more intermediate metal oxide contact hydroboration materializations Compound, borate compound and hydrogen or the two the step of further comprise connecing one or more intermediate metal oxides Touch hydrochloric acid, chlorine (Cl₂) or the two.

35. the method described in claim 24, wherein the step of making the metal nanoparticle contact boric acid further comprises making The metal nanoparticle contact hydrogen (H₂)。

36. the method described in claim 24, further comprises forming metal boride crystal.

37. the method described in claim 36, wherein being formed, the metal boride crystal is included in environment temperature and pressure is incubated Educate the solution of the metal boride.

38. the method described in claim 36, wherein being formed, the metal boride crystal is included in environment temperature and pressure is incubated Educate the solution of metal boride up to 24 hours to 48 hours.

39. the method described in claim 37, further comprises stirring the solution wherein forming the metal boride crystal.

40. the method described in claim 24, further comprises using metal boride described in iron oxide-coated.

41. the method described in claim 24, wherein methods described are carried out in environment temperature and pressure.

42. the method described in claim 24, wherein methods described are carried out in single reaction container.