Oxygen carrier materials that include iron and one or more additional metals, and methods of making the same

Abstract

An oxygen carrier material may include a first composition. At least 95 wt.% of the first composition may consist of: from 0.001 parts by mole to 0.999 parts by mole of iron; from 0.001 parts by mole to 0.999 parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc; from 0.04 parts by mole to 0.8 parts by mole of one or more alkali metals; from 0.02 parts by mole to 0.4 parts by mole of tungsten; from 0 parts by mole to 3 parts by mole of titanium; and from 1 parts by mole to 10 parts by mole of oxygen. The sum of the parts by mole of the iron and the parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc may be equal to 1 part by mole.

Description

OXYGEN CARRIER MATERIALS THAT INCLUDE IRON AND ONE OR MORE ADDITIONAL METALS, AND METHODS OF MAKING THE SAMECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 595,991 filed November 3, 2023, the contents of which are incorporated in their entirety herein.TECHNICAL FIELD

[0002] Embodiments of the present disclosure generally relate to chemical processing and, in particular, to oxygen carrier materials utilized in chemical processing.BACKGROUND

[0003] Some chemical processes that utilize oxygen as a reactant utilize oxygen carrier materials. In such processes, oxygen may be delivered or “carried” in a cycle via a reduction and subsequent oxidation of the oxygen carrier material. In such processes the oxygen carried by the oxygen carrier material may be utilized as the source of oxygen. In particular, oxygen carrier materials may be utilized in cyclical chemical processes where oxygen may be added to and removed from the oxygen carrier material as it is used throughout the entire process. Such materials may be utilized in a wide variety of chemical processing methods.SUMMARY

[0004] There is a continued need for oxygen carrier materials that are suitable for use with particular chemical processes. Described herein are particular oxygen carrier materials that include at least iron; one or more of manganese, cerium, cobalt, copper, nickel, or zinc; or more alkali metals; tungsten; and oxygen; in particular amounts relative to one another. It has been found that the oxygen carrier materials described herein, according to one or more embodiments, may have relatively high selectivity for combusting hydrogen gas over combusting hydrocarbons. Such oxygen carrier materials may be utilized in processes that form olefinic compounds, among other contemplated uses, as described in detail herein.

[0005] According to one or more embodiments of the present disclosure, an oxygen carrier material may comprise a first composition. At least 95 wt.% of the first composition may consist of: from 0.001 parts by mole to 0.999 parts by mole of iron; from 0.001 parts by mole to 0.999 parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc; from 0.04 parts by mole to 0.8 parts by mole of one or more alkali metals; from 0.02 partsby mole to 0.4 parts by mole of tungsten; from 0 parts by mole to 3 parts by mole of titanium; and from 1 parts by mole to 10 parts by mole of oxygen. The sum of the parts by mole of the iron and the parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc may be equal to 1 part by mole.

[0006] Additional features and advantages of the present disclosure will be set forth in the detailed description, which follows, and in part will be apparent to those skilled in the art from that description or recognized by practicing the embodiments described herein, including the detailed description, which follows the claims, as well as the appended drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The following detailed description of specific embodiments of the present disclosure can be best understood when read in conjunction with the following drawing(s), where like structure is indicated with like reference numerals and in which:

[0008] FIG. 1 is a schematic depiction of a reactor system suitable for use with an oxygen carrier material, according to one or more embodiments described herein.

[0009] Additional features and advantages of the present disclosure will be set forth in the detailed description, which follows, and in part will be apparent to those skilled in the art from that description or recognized by practicing the embodiments described herein, including the detailed description, which follows the claims, as well as the appended drawings.

[0010] It is to be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments and are incorporated into and constitute a part of this specification. The drawings illustrate the various embodiments described herein, and together with the description, explain the principles and operations of the claimed subject matter.DETAILED DESCRIPTION

[0011] Specific embodiments of the present application will now be described. The technical aspects of the present application may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth in this detailed description.

[0012] Generally, described in this disclosure are various embodiments of oxygen carrier materials. As described herein, the oxygen carrier materials may comprise a first composition and, optionally, one or more additional materials. In one or more embodiments, the first compositionmay comprise or consist of active materials, which are materials that, in general, contribute to the oxygen carrying functionality and / or the selectivity for hydrogen combustion of the oxygen carrier materials described herein. In general, in the embodiments described herein, at least 95 wt.% of the first composition may consist of iron (Fe); one or more of manganese (Mn), cerium (Ce), cobalt (Co), copper (Cu), nickel (Ni), or zinc (Zn); one or more alkali metals, tungsten (W), oxygen (O), and optionally titanium (Ti), in amounts defined by particular ratios between these various components.

[0013] In embodiments, the oxygen carrier material, in addition to the first composition, may further comprise one or more additional materials. In embodiments, the one or more additional materials may function as binders in the oxygen carrier materials. In some embodiments, the binders may not substantially contribute to the oxygen carrying and / or catalytic functionality of the oxygen carrier materials. Binders may generally enhance the physical properties of the oxygen carrier material. According to embodiments, the one or more additional materials may be chosen from oxides of silicon, aluminum, calcium, magnesium, zirconium, niobium, or combinations thereof. In general, the additional material or materials may not include elements that are present in the first composition, aside from oxygen. It is contemplated that mixtures of various oxides of an element may be included in the one or more additional materials. Without limitation, in one or more embodiments, additional materials may be chosen from those disclosed in "Progress in Chemical-Looping Combustion and Reforming technologies" Progress in Energy and Combustion Science 38 (2012) 215-282 and "Chemical Looping Systems for Fossil Energy Conversions", Liang-Shih Fan, published by WILEY 2010. For example, in certain embodiments, suitable additional materials that may act as binders include, without limitation, silica (colloidal, fumed, crystalline, amorphous), alumina (alpha, theta, or gamma crystal phases), CaAlxOy, MgAbC , zirconia, inorganic clays (e.g., kaolin, other alumina-silicates), and glass materials (such as glass fibers).

[0014] According to one or more embodiments, the oxygen carrier material may comprise at least 75 wt.%, at least 80 wt.%, at least 85 wt.%, at least 90 wt.%, at least 95 wt.%, at least 99 wt.%, at least 99.9 wt.%, or may consist of the combination of the first composition and the one or more additional materials. For example, the oxygen carrier material may consist of the combination of the first composition and the one or more additional materials, where the one or more additional materials may act as binders and fill the balance of the oxygen carrier material that is not part of the first composition.

[0015] In one or more embodiments, the oxygen carrier material may comprise the first composition in an amount of from 1 wt.% to 5 wt.%, from 5 wt.% to 10 wt.%, from 10 wt.% to 15 wt.%, from 15 wt.% to 20 wt.%, from 20 wt.% to 25 wt.%, from 25 wt.% to 30 wt.%, from 30 wt.% to 35 wt.%, from 35 wt.% to 40 wt.%, from 40 wt.% to 45 wt.%, from 45 wt.% to 50 wt.%, from 50 wt.% to 55 wt.%, from 55 wt.% to 60 wt.%, from 60 wt.% to 65 wt.%, from 65 wt.% to 70 wt.%, from 70 wt.% to 75 wt.%, from 75 wt.% to 80 wt.%, from 80 wt.% to 85 wt.%, from 85 wt.% to 90 wt.%, from 90 wt.% to 95 wt.%, from 95 wt.% to 100 wt.%, or any combination of one or more of these ranges. For example, the oxygen carrier material may comprise at least 5 wt.%, at least 10 wt.%, at least 15 wt.%, at least 20 wt.%, at least 25 wt.%, at least 30 wt.%, at least 35 wt.%, at least 40 wt.%, at least 45 wt.%, at least 50 wt.%, at least 55 wt.%, at least 60 wt.%, at least 65 wt.%, at least 70 wt.%, at least 75 wt.%, at least 80 wt.%, at least 85 wt.%, at least 90 wt.%, or even at least 95 wt.% of the first composition. In some embodiments, the oxygen carrier material may comprise the first composition in an amount of at least 99 wt.%, or at least 99.9 wt.%. In some embodiments, the oxygen carrier material may consist of the first composition.

[0016] In additional embodiments, the oxygen carrier material may comprise the one or more additional materials. According to embodiments, the oxygen carrier material may comprise from 1 wt.% to 50 wt.% of the one or more additional materials. For example, the one or more additional materials may be present in the oxygen carrier material in an amount of from 1 wt.% to 5 wt.%, from 5 wt.% to 10 wt.%, from 10 wt.% to 15 wt.%, from 15 wt.% to 20 wt.%, from 20 wt.% to 25 wt.%, from 25 wt.% to 30 wt.%, from 30 wt.% to 35 wt.%, from 35 wt.% to 40 wt.%, from 40 wt.% to 45 wt.%, from 45 wt.% to 50 wt.%, or any combination of one or more of these ranges. For example, the oxygen carrier material may comprise less than or equal to 50 wt.% and at least 5 wt.%, at least 10 wt.%, at least 15 wt.%, at least 20 wt.%, at least 25 wt.%, at least 30 wt.%, at least 35 wt.%, at least 40 wt.%, or at least 45 wt.%, of the one or more additional materials. In additional embodiment, the oxygen carrier material may comprise the one or more additional material in an amount of at least 1 wt.% and less than or equal to 5 wt.%, less than or equal to 10 wt.%, less than or equal to 15 wt.%, less than or equal to 20 wt.%, less than or equal to 25 wt.%, less than or equal to 30 wt.%, less than or equal to 35 wt.%, less than or equal to 40 wt.%, or less than or equal to 45 wt.%.

[0017] As described herein, the relative amounts of the materials of the first composition are described in terms of relative amounts of atoms of each element that are included in the first composition. Also, as described herein, the components of the oxygen carrier material may bedescribed in amounts relative to other components. For example, described herein are components represented in amounts described as “parts by mole.” Parts by mole, as used herein, describes the molar ratio of one component with another, and does not restrict the total number or moles of a particular substituent. For example, iron may be present in an amount of 1 part by mole, and oxygen may be present in an amount of from 1 part by mole to 10 parts by mole, which means all compositions which meet this ratio of iron atoms to oxygen atoms fall within embodiments described herein regardless of the raw amount of these constituents. In general, and unless stated otherwise, where multiple elements or other materials are listed together as being in a specific amount, this refers to the total of the combination of all of these elements or other materials, even when not explicitly stating that the “sums” of these elements or the “combination” of these elements is in the amount specified. For example, when “one or more alkali metals” are listed in an amount, the amount refers to the combination of all alkali metals.

[0018] Now turning to the first composition of the oxygen carrier material, in one or more embodiments, at least 95 wt.% of the first composition may consist of iron; one or more of manganese, cerium, cobalt, copper, nickel, or zinc; one or more alkali metals; tungsten; oxygen; and optionally titanium. For example, at least 96 wt.%, at least 97 wt.%, at least 98 wt.%, at least 99 wt.%, at least 99.5 wt.%, or at least 99.9 wt.% of the first composition may consist of iron; one or more alkali metals; one or more of manganese, cerium, cobalt, copper, nickel, or zinc; tungsten; oxygen; and optionally titanium. In some embodiment, the first composition may consist of iron; one or more of manganese, cerium, cobalt, copper, nickel, or zinc; one or more alkali metals; tungsten; oxygen; and optionally titanium.

[0019] In one or more embodiments, iron and one or more of manganese, cerium, cobalt, copper, nickel, or zinc may be present in the first composition. For compactness in this disclosure, manganese, cerium, cobalt, copper, nickel, and zinc may be referred to as “dopant metals,” where reference to the one or more “dopant metals” refers to the one or more of manganese, cerium, cobalt, copper, nickel, and zinc. As is described herein, the sum of the parts by mole of iron and the parts by mole of combination of the one or more dopant metals may be equal to 1 part by mole. Without being bound by any particular theory, it is believed that iron and the one or more dopant metals may work as the major constituents that bind and unbind from oxygen in redox reactions by changing of their oxidation states.

[0020] Additionally, without being bound by any particular theory, it is believed that the presence of one or more of manganese, cerium, cobalt, copper, nickel, and zinc may have an effectin promoting combustion of methane in the regeneration unit 120 when methane is utilized as a fuel gas. That is, embodiments that do not include one or more of these dopant metals may not allow for combustion of methane in regeneration in the presence of oxygen as well as the embodiments described herein.

[0021] In such embodiments, iron may be present in the first composition, where iron is present in the first composition in a relative amount of from 0.001 parts by mole to 0.999 parts by mole. In one or more embodiments, the first composition may comprise iron in a relative amount of from 0.001 parts by mole to 0.1 parts by mole, from 0.1 parts by mole to 0.2 parts by mole, from 0.2 parts by mole to 0.3 parts by mole, from 0.3 parts by mole to 0.4 parts by mole, from 0.4 parts by mole to 0.5 parts by mole, from 0.5 parts by mole to 0.6 parts by mole, from 0.6 parts by mole to 0.7 parts by mole, from 0.7 parts by mole to 0.8 parts by mole, from 0.8 parts by mole to 0.9 parts by mole, from 0.9 parts by mole to 0.999 part by mole, or any combination of one or more of these ranges.

[0022] In additional embodiments, the first composition may comprise iron in a relative amount of less than or equal to 0.999 parts by mole and at least 0.1 parts by mole, at least 0.2 parts by mole, at least 0.3 parts by mole, at least 0.4 parts by mole, at least 0.5 parts by mole, at least 0.6 parts by mole, at least 0.7 parts by mole, at least 0.8 parts by mole, or at least 0.9 parts by mole.

[0023] In additional embodiments, the first composition may comprise iron in a relative amount of at least 0.001 parts by mole and less than or equal to 0.1 parts by mole, less than or equal to 0.2 parts by mole, less than or equal to 0.3 parts by mole, less than or equal to 0.4 parts by mole, less than or equal to 0.5 parts by mole, less than or equal to 0.6 parts by mole, less than or equal to 0.7 parts by mole, less than or equal to 0.8 parts by mole, or less than or equal to 0.9 parts by mole.

[0024] According to embodiments, the first composition may comprise the combination of the one or more dopant metals (i.e., manganese, cerium, cobalt, copper, nickel, and zinc) in a relative amount of from 0.001 parts by mole to 0.999 parts by mole. In one or more embodiments, the first composition may comprise the combination of the dopant metals in a relative amount of from 0.001 parts by mole to 0.1 parts by mole, from 0.1 parts by mole to 0.2 parts by mole, from 0.2 parts by mole to 0.3 parts by mole, from 0.3 parts by mole to 0.4 parts by mole, from 0.4 parts by mole to 0.5 parts by mole, from 0.5 parts by mole to 0.6 parts by mole, from 0.6 parts by mole to 0.7 parts by mole, from 0.7 parts by mole to 0.8 parts by mole, from 0.8 parts by mole to 0.9 parts by mole, from 0.9 parts by mole to 0.999 part by mole, or any combination of one or more of these ranges.

[0025] In additional embodiments, the first composition may comprise the combination of the one or more dopant metals in a relative amount of at least 0.1 parts by mole, at least 0.2 parts by mole, at least 0.3 parts by mole, at least 0.4 parts by mole, at least 0.5 parts by mole, at least 0.6 parts by mole, at least 0.7 parts by mole, at least 0.8 parts by mole, or at least 0.9 parts by mole, and less than or equal to 0.999 parts by mole. In additional embodiments, the first composition may comprise the combination of the one or more dopant metals in a relative amount of less than or equal to 0.1 parts by mole, less than or equal to 0.2 parts by mole, less than or equal to 0.3 parts by mole, less than or equal to 0.4 parts by mole, less than or equal to 0.5 parts by mole, less than or equal to 0.6 parts by mole, less than or equal to 0.7 parts by mole, less than or equal to 0.8 parts by mole, or less than or equal to 0.9 parts by mole, and at least 0.001 parts by mole.

[0026] It is contemplated that, in some embodiments, only a single dopant metal may be present in the first composition. That is only one of manganese, cerium, cobalt, copper, nickel, or zinc may be present in the first composition. In additional embodiments, any combination of two, three, four, or five, or all of, manganese, cerium, cobalt, copper, nickel, and zinc may be present in the first composition. For any of these embodiments, the above described ranges for the relative amount of dopant metals may apply to a single, two, three, four, five, or six elements of the dopant metals chosen from manganese, cerium, cobalt, copper, nickel, and zinc.

[0027] In one or more embodiments, one or more alkali metals may be present in the first composition, where the one or more alkali metals may be present in the first composition in a relative amount of from 0.04 parts by mole to 0.8 parts by mole. Without being bound by any particular theory, it is believed that the presence of this amount of alkali metals may improve selectivity to hydrogen combustion over combustion of hydrocarbons.

[0028] According to embodiments, the one or more alkali metals may be chosen from lithium, sodium, and potassium, where the combination of lithium, sodium, and potassium is in a relative amount of from 0.04 parts by mole to 0.8 parts by mole. In some embodiments, lithium is present in the first composition but sodium and potassium are not. In additional embodiments, sodium is present in the first composition but lithium and potassium are not. In additional embodiments, potassium is present in the first composition but sodium and lithium are not. In some yet additional embodiments, lithium and sodium are present in the first composition and potassium is not, sodium and potassium are present in the first composition at lithium is not, or potassium and lithium are present in the first composition and sodium is not. In some embodiments, lithium, sodium, and potassium are present in the first composition.

[0029] In some embodiments, the one or more alkali metals may be present in the first composition in a relative amount of less than or equal to 0.8 parts by mole and at least 0.08 parts by mole, at least 0.12 parts by mole, at least 0.16 parts by mole, at least 0.20 parts by mole, at least 0.24 parts by mole, at least 0.28 parts by mole, at least 0.32 parts by mole, at least 0.36 parts by mole, at least 0.40 parts by mole, at least 0.44 parts by mole, at least 0.48 parts by mole, at least 0.52 parts by mole, at least 0.56 parts by mole, at least 0.60 parts by mole, at least 0.64 parts by mole, at least 0.68 parts by mole, at least 0.72 parts by mole, or least 0.76 parts by mole.

[0030] In additional embodiments, the one or more alkali metals may be present in the first composition in a relative amount of at least 0.04 parts by mole and less than or equal to 0.76 parts by mole, less than or equal to 0.72 parts by mole, less than or equal to 0.68 parts by mole, less than or equal to 0.64 parts by mole, less than or equal to 0.60 parts by mole, less than or equal to 0.56 parts by mole, less than or equal to 0.52 parts by mole, less than or equal to 0.48 parts by mole, less than or equal to 0.44 parts by mole, less than or equal to 0.40 parts by mole, less than or equal to 0.36 parts by mole, less than or equal to 0.32 parts by mole, less than or equal to 0.28 parts by mole, less than or equal to 0.24 parts by mole, less than or equal to 0.20 parts by mole, less than or equal to 0.16 parts by mole, less than or equal to 0.12 parts by mole, or less than or equal to 0.08 parts by mole.

[0031] In additional embodiments, the one or more alkali metals may be present in the first composition in a relative amount of from 0.04 parts by mole to 0.08 parts by mole, from 0.08 parts by mole to 0.12 parts by mole, from 0.12 parts by mole to 0.16 parts by mole, from 0.16 parts by mole to 0.20 parts by mole, from 0.20 parts by mole to 0.24 parts by mole, from 0.24 parts by mole to 0.28 parts by mole, from 0.28 parts by mole to 0.32 parts by mole, from 0.32 parts by mole to 0.36 parts by mole, from 0.36 parts by mole to 0.40 parts by mole, from 0.40 parts by mole to 0.44 parts by mole, from 0.44 parts by mole to 0.48 parts by mole, from 0.48 parts by mole to 0.52 parts by mole, from 0.52 parts by mole to 0.56 parts by mole, from 0.56 parts by mole to 0.60 parts by mole, from 0.60 parts by mole to 0.64 parts by mole, from 0.64 parts by mole to 0.68 parts by mole, from 0.68 parts by mole to 0.72 parts by mole, from 0.72 parts by mole to 0.76 parts by mole, from 0.76 parts by mole to 0.80 parts by mole, or any combination of one or more of these ranges.

[0032] In one or more embodiments, tungsten may be present in the first composition, where the tungsten may be present in the first composition in a relative amount of from 0.02 parts by mole to 0.4 parts by mole. Without being bound by theory, it is believed that the presence oftungsten in this amount may regulate the oxygen release from iron, which may suppress the oxidation of hydrocarbons.

[0033] In some embodiments, tungsten may be present in the first composition in a relative amount of less than or equal to 0.4 parts by mole and at least 0.06 parts per mole, at least 0.08 parts per mole, at least 0.10 parts per mole, at least 0.12 parts per mole, at least 0.14 parts per mole, at least 0.16 parts per mole, at least 0.18 parts per mole, at least 0.20 parts per mole, at least 0.22 parts per mole, at least 0.24 parts per mole, at least 0.26 parts per mole, at least 0.28 parts per mole, at least 0.30 parts per mole, at least 0.32 parts per mole, at least 0.34 parts per mole, at least 0.36 parts per mole, or even at least 0.38 parts per mole.

[0034] In additional embodiments, tungsten may be present in the first composition in a relative amount of at least 0.02 parts by mole and less than or equal to 0.38 parts by mole, less than or equal to 0.36 parts by mole, less than or equal to 0.34 parts by mole, less than or equal to 0.32 parts by mole, less than or equal to 0.30 parts by mole, less than or equal to 0.28 parts by mole, less than or equal to 0.26 parts by mole, less than or equal to 0.24 parts by mole, less than or equal to 0.22 parts by mole, less than or equal to 0.20 parts by mole, less than or equal to 0.18 parts by mole, less than or equal to 0.16 parts by mole, less than or equal to 0.14 parts by mole, less than or equal to 0.12 parts by mole, less than or equal to 0.10 parts by mole, less than or equal to 0.08 parts by mole, less than or equal to 0.06 parts by mole, or even less than or equal to 0.04 parts by mole, and at least 0.02 parts by mole.

[0035] In additional embodiments, tungsten may be present in the first composition in a relative amount of from 0.02 parts by mole to 0.04 parts by mole, from 0.04 parts by mole to 0.06 parts by mole, from 0.06 parts by mole to 0.08 parts by mole, from 0.08 parts by mole to 0.10 parts by mole, from 0.10 parts by mole to 0.12 parts by mole, from 0.12 parts by mole to 0.14 parts by mole, from 0.14 parts by mole to 0.16 parts by mole, from 0.16 parts by mole to 0.18 parts by mole, from 0.18 parts by mole to 0.20 parts by mole, from 0.20 parts by mole to 0.22 parts by mole, from 0.22 parts by mole to 0.24 parts by mole, from 0.24 parts by mole to 0.26 parts by mole, from 0.26 parts by mole to 0.28 parts by mole, from 0.28 parts by mole to 0.30 parts by mole, from 0.30 parts by mole to 0.32 parts by mole, from 0.32 parts by mole to 0.34 parts by mole, from 0.34 parts by mole to 0.36 parts by mole, from 0.36 parts by mole to 0.38 parts by mole, from 0.38 parts by mole to 0.40 parts by mole, or any combination of one or more of these ranges.

[0036] In one or more embodiments, oxygen may be present in the first composition in a relative amount of from 1 part by mole to 10 parts by mole. The amount of oxygen may depend on the oxidation state of the oxygen carrier material, where more oxygen may be present in embodiments when the oxygen carrier material is storing oxygen atoms and less oxygen may be present once such oxygen has been provided for reaction and prior to regeneration. In general, the amount of oxygen may vary at different points in processing to form olefins, as is described herein.

[0037] In some embodiments, oxygen may be present in the first composition in a relative amount of less than or equal 10 parts by mole and at least 1.25 parts per mole, at least 1.5 parts per mole, at least 1.75 parts per mole, at least 2 parts per mole, at least 2.25 parts per mole, at least 2.5 parts per mole, at least 2.75 parts per mole, at least 3 parts per mole, at least 3.25 parts per mole, at least 3.5 parts per mole, at least 3.75 parts per mole, at least 4 parts per mole, at least 4.25 parts per mole, at least 4.5 parts per mole, at least 4.75 parts per mole, at least 5 parts per mole, at least 5.25 parts per mole, at least 5.5 parts per mole, at least 5.75 parts per mole, at least 6 parts per mole, at least 6.25 parts per mole, at least 6.5 parts per mole, at least 6.75 parts per mole, at least 7 parts per mole, at least 7.25 parts per mole, at least 7.5 parts per mole, at least 7.75 parts per mole, at least 8 parts per mole, at least 8.25 parts per mole, at least 8.5 parts per mole, at least 8.75 parts per mole, at least 9 parts per mole, at least 9.25 parts per mole, at least 9.5 parts per mole, or even at least 9.75 parts per mole.

[0038] In additional embodiments, oxygen may be present in the first composition in a relative amount of at least 1 part by mole and less than or equal to 1.25 parts by mole, less than or equal to 1.5 parts by mole, less than or equal to 1.75 parts by mole, less than or equal to 2 parts by mole, less than or equal to 2.25 parts by mole, less than or equal to 2.5 parts by mole, less than or equal to 2.75 parts by mole, less than or equal to 3 parts by mole, less than or equal to 3.25 parts by mole, less than or equal to 3.5 parts by mole, less than or equal to 3.75 parts by mole, less than or equal to 4 parts by mole, less than or equal to 4.25 parts by mole, less than or equal to 4.5 parts by mole, less than or equal to 4.75 parts by mole, less than or equal to 5 parts by mole, less than or equal to 5.25 parts by mole, less than or equal to 5.5 parts by mole, less than or equal to 5.75 parts by mole, less than or equal to 6 parts by mole, less than or equal to 6.25 parts by mole, less than or equal to 6.5 parts by mole, less than or equal to 6.75 parts by mole, less than or equal to 7 parts by mole, less than or equal to 7.25 parts by mole, less than or equal to 7.5 parts by mole, less than or equal to 7.75 parts by mole, less than or equal to 8 parts by mole, less than or equal to 8.25 parts by mole, less than or equal to 8.5 parts by mole, less than or equal to 8.75 parts by mole, lessthan or equal to 9 parts by mole, less than or equal to 9.25 parts by mole, less than or equal to 9.5 parts by mole, or less than or equal to 9.75 parts by mole.

[0039] In additional embodiments, oxygen may be present in the first composition in a relative amount of from 1 part by mole to 1.25 parts by mole, from 1.25 parts by mole to 1.5 parts by mole, from 1.5 parts by mole to 1.75 parts by mole, from 1.75 parts by mole to 2 parts by mole, from 2 parts by mole to 2.25 parts by mole, from 2.25 parts by mole to 2.5 parts by mole, from 2.5 parts by mole to 2.75 parts by mole, from 2.75 parts by mole to 3 parts by mole, from 3 parts by mole to 3.25 parts by mole, from 3.25 parts by mole to 3.5 parts by mole, from 3.5 parts by mole to 3.75 parts by mole, from 3.75 parts by mole to 4 parts by mole, from 4 parts by mole to 4.25 parts by mole, from 4.25 parts by mole to 4.5 parts by mole, from 4.5 parts by mole to 4.75 parts by mole, from 4.75 parts by mole to 5 parts by mole, from 5 parts by mole to 5.25 parts by mole, from 5.25 parts by mole to 5.5 parts by mole, from 5.5 parts by mole to 5.75 parts by mole, from 5.75 parts by mole to 6 parts by mole, from 6 parts by mole to 6.25 parts by mole, from 6.25 parts by mole to 6.5 parts by mole, from 6.5 parts by mole to 6.75 parts by mole, from 6.75 parts by mole to 7 parts by mole, from 7 parts by mole to 7.25 parts by mole, from 7.25 parts by mole to 7.5 parts by mole, from 7.5 parts by mole to 7.75 parts by mole, from 7.75 parts by mole to 8 parts by mole, from 8 parts by mole to 8.25 parts by mole, from 8.25 parts by mole to 8.5 parts by mole, from 8.5 parts by mole to 8.75 parts by mole, from 8.75 parts by mole to 9 parts by mole, from 9 parts by mole to 9.25 parts by mole, from 9.25 parts by mole to 9.5 parts by mole, from 9.5 parts by mole to 9.75 parts by mole, from 9.75 parts by mole to 10 parts by mole, or any combination of one or more of these ranges.

[0040] In one or more embodiments, the first composition may optionally comprise titanium. That is, in some embodiments, titanium may be present in the first composition and, in other embodiments, titanium may not be present in the first composition. In one or more embodiments, titanium may be present in the first composition in a relative amount of from 0 parts by mole to 3 parts by mole. In some embodiments, titanium may be present in the first composition in a relative amount of from 0.001 parts by mole to 3 parts by mole. Without being bound by theory, it is believed that the presence of titanium may improve mechanical stability of the oxygen carrier material. Moreover, titanium in combination with iron and alkali metals may form crystal phases containing alkali, iron, and titanium (e.g., prederite and hollandite) as opposed to ilmenite, which may unfavorably promote reduction.

[0041] In some embodiments, titanium may be present in the first composition in a relative amount of at least 0.25 parts per mole, at least 0.5 parts per mole, at least 0.75 parts per mole, at least 1 parts per mole, at least 1.25 parts per mole, at least 1.5 parts per mole, at least 1.75 parts per mole, at least 2 parts per mole, at least 2.25 parts per mole, at least 2.5 parts per mole, or at least 2.75 parts per mole, and less than or equal 3 parts by mole.

[0042] In additional embodiments, titanium may be present in the first composition in a relative amount of less than or equal to 0.25 parts by mole, less than or equal to 0.5 parts by mole, less than or equal to 0.75 parts by mole, less than or equal to 1 part by mole, less than or equal to 1.25 parts by mole, less than or equal to 1.5 parts by mole, less than or equal to 1.75 parts by mole, less than or equal to 2 parts by mole, less than or equal to 2.25 parts by mole, less than or equal to 2.5 parts by mole, or less than or equal to 2.75 parts by mole, and at least 0 parts by mole or at least 0.001 parts by mole.

[0043] In additional embodiments, titanium may be present in the first composition in a relative amount of from 0 parts by mole to 0.25 parts by mole, from 0.001 parts by mole to 0.25 parts by mole, from 0.25 parts by mole to 0.5 parts by mole, from 0.5 parts by mole to 0.75 parts by mole, from 0.75 parts by mole to 1 part by mole, from 1 part by mole to 1.25 parts by mole, from 1.25 parts by mole to 1.5 parts by mole, from 1.5 parts by mole to 1.75 parts by mole, from 1.75 parts by mole to 2 parts by mole, from 2 parts by mole to 2.25 parts by mole, from 2.25 parts by mole to 2.5 parts by mole, from 2.5 parts by mole to 2.75 parts by mole, from 2.75 parts by mole to 3 parts by mole, or any combination of one or more of these ranges.

[0044] In one or more embodiments, the oxygen-carrier material may be capable of fluidization. In some embodiments, the oxygen carrier material may have a median particle size (D50) of from 50 pm to 300 pm, such as from 50 pm to 250 pm, from 50 pm to 200 pm, from 50 pm to 150 pm, from 50 pm to 100 pm, from 100 pm to 300 pm, from 100 pm to 250 pm, from 100 pm to 200 pm, from 100 pm to 150 pm, from 150 pm to 300 pm, from 150 pm to 250 pm, from 150 pm to 200 pm, from 200 pm to 300 pm, from 200 pm to 250 pm, or from 250 pm to 300 pm.

[0045] In some embodiments, the oxygen-carrier material may exhibit properties known in the industry as “Geldart A” or “Geldart B” properties. Particles may be classified as “Group A” or “Group B” according to D. Geldart, Gas Fluidization Technology, John Wiley & Sons (New York, 1986), 34-37; and D. Geldart, “Types of Gas Fluidization,” Powder Technol. 7 (1973) 285-292, which are incorporated herein by reference in their entireties.

[0046] Group A is understood by those skilled in the art as representing an aeratable powder, having a bubble-free range of fluidization; a high bed expansion; a slow and linear deaeration rate; bubble properties that may include a predominance of splitting / recoalescing bubbles, with a maximum bubble size and large wake; high levels of solids mixing and gas backmixing, assuming equal U-Umf (U is the velocity of the carrier gas, and Umf is the minimum fluidization velocity, typically though not necessarily measured in meters per second, m / s, i.e., there is excess gas velocity); axisymmetric slug properties; and no spouting, except in very shallow beds. The properties listed tend to improve as the mean particle size decreases, assuming equal cfp; or as the <45 micrometers (pm) proportion is increased; or as pressure, temperature, viscosity, and density of the gas increase. In general, the particles may exhibit a small mean particle size and / or low particle density (<1.4 grams per cubic centimeter, g / cm3), fluidize easily, with smooth fluidization at low gas velocities, and may exhibit controlled bubbling with small bubbles at higher gas velocities.

[0047] Group B is understood by those skilled in the art as representing a “sand-like” powder that starts bubbling at Umf; that exhibits moderate bed expansion; a fast deaeration; no limits on bubble size; moderate levels of solids mixing and gas backmixing, assuming equal U-Umf; both axisymmetric and asymmetric slugs; and spouting in only shallow beds. These properties tend to improve as mean particle size decreases, but particle size distribution and, with some uncertainty, pressure, temperature, viscosity, or density of gas seem to do little to improve them. In general, most of the particles having a particle size (cfp) of 40 pm <cfp <500 pm when the density (pp) is 1.4 <pp <4 g / cm3, and preferably 60 pm <cfp <500 pm when the density (pp) is 4 g / cm3and 250 pm <cfp <100 pm when the density (pp) is 1 g / cm3.

[0048] In one or more embodiments, the oxygen carrier materials described herein may be prepared by a variety of synthetic techniques including solid-state synthesis, or wet or dry impregnation followed by drying and high-temperature calcination, as known to those skilled in the art. In general, various components in the first composition can be added as solid powders in their oxide form, then well-mixed or homogenized, followed by calcination in air at high temperatures. Alternatively, some components in the first composition can be incorporated by completely (wet or dry impregnation) or partially (slurry impregnation) dissolving their precursors in water, and then combining them with solid powders of remaining components, followed by drying and high-temperature calcination in air. Optionally, small amount of the additionalmaterials described herein can be added during the synthesis of the oxygen carrier to provide physical strength and stability.

[0049] In some embodiments, as described hereinabove, the oxygen carrier can be prepared by impregnation. The impregnation may utilize wet impregnation or dry impregnation (sometimes referred to as incipient wetness impregnation). The impregnation may utilize an aqueous solution that includes some components of the first composition For example, in various embodiments, the aqueous solution may comprise the one or more precursors of alkali metals and / or tungsten. In some embodiments, the aqueous solution may comprise potassium tungstate, potassium carbonate, potassium sulfate, potassium nitrate, potassium acetate, ammonium para tungstate, ammonium meta tungstate, tungstic acid, or combinations thereof. In one or more embodiments, the aqueous solution may have a pH of greater than 7. For example, the aqueous solution may have a pH of greater than 7.5, greater than 8, greater than 8.5, greater than 9, greater than 9.5, greater than 10, greater than 10.5, greater than 11, or even greater than 11.5. In some embodiments, multiple impregnation steps may occur to impregnate different materials.

[0050] The impregnated material may then be dried after impregnation. In some embodiments, the impregnated material may be dried under air. In one or more embodiments, the impregnated material may be dried at a temperature of less than 200 °C, such as less than 175 °C, less than 150 °C, less than 125 °C, less than 100 °C, less than 75 °C, or even less than 50 °C. In certain embodiments, impregnation can be done more than once with the aqueous solution, the impregnated material may be dried between each impregnation.

[0051] The dried impregnated material may then be calcined to produce the oxygen-carrier material. In one or more embodiments, the calcination may be at a temperature of greater than 600 °C, such as greater than 700 °C, greater than 800 °C, greater than 900 °C, greater than 1000 °C, greater than 1100 °C, or even greater than 1200 °C. In one or more embodiments, the dried impregnated material may be calcined under air. In embodiments where multiple impregnation steps are utilized, the impregnated material may be calcined between each impregnation. In embodiments, the dried impregnated material may be calcined in air for more than 1 hour. For example, the dried impregnated material may be calcined in air for more than 2 hours, more than 4 hours, more than 10 hours, or even more than 20 hours.

[0052] In some embodiments, the oxygen-carrier materials may be utilized in processes comprising fluidized beds or moving beds or circulating fluidized bed (CFB). In such embodiments, it may be desirable to have oxygen carries as engineered particles with “Geldart A”or “Geldart B” properties. Without being limited by theory, in one or more embodiments, it is believed that the choice in methods of making engineered particles of oxygen-carrier materials such as manufacturing techniques like spray drying, high-shear granulation, and fluidized bed granulation can be utilized followed by drying and high temperature calcination to achieve fluidizable particles.

[0053] According to one or more embodiments of the present disclosure, a method for producing olefinic compounds is provided that utilizes the oxygen carrier materials described herein. As used herein, the term “olefinic compounds” refers to hydrocarbons having one or more carbon-carbon double bonds apart from the formal double bonds in aromatic compounds. For example, ethylene and styrene are olefinic compounds, but ethylbenzene would not be an olefinic compound as the only double bonds present in ethylbenzene are formal double bonds present as part of the aromatic structure.

[0054] Now referring to FIG. 1, a reactor system 100 that may be used with the methods of the present disclosure is shown, but other reactor systems that would be suitable for the presently disclosed methods are contemplated as suitable. FIG. 1 is a simplified system, and other systems are contemplated. Additionally, in FIG. 1, a wide variety of reactor types are contemplated as potentially suitable for the methods described herein. For example, the oxygen carrier materials of the present disclosure may be utilized in the systems and methods that are disclosed in at least PCT International Application No. PCT / US23 / 73963, entitled “Methods For Dehydrogenating Hydrocarbons By Thermal Dehydrogenation” and International Patent Publication WO 2020 / 046978, entitled “Methods for Dehydrogenating Hydrocarbons,” the teachings of each of which are incorporated by reference in their entirety herein. The technical aspects of these disclosures may further describe the methods and systems described herein with respect to FIG. 1. Additionally, it is noted that the steps indicated by FIG. 1 are not to be interpreted as essential steps, particularly in view of the methods of the appended claims.

[0055] Referring still to FIG. 1, the reactor system 100 may include a reactor 110 and a regeneration unit 120. In one or more embodiments, the reactor 110 may be a fluidized bed reactor. Generally, a feed stream 101 may be passed into the reactor 110 and be processed in the reactor 110 to form a product stream 102 that includes one or more olefinic compounds. As described in detail herein, according to one or more embodiments, the oxygen carrier material may be cycled between the reactor 110 and the regeneration unit 120, where the oxygen carrier material enters the reactor 110 in an oxygen-rich state, provides oxygen in the reactor 110, leaves the reactor 110in an oxygen-diminished state, and may be regenerated to an oxygen-rich state in the regeneration unit 120.

[0056] In one or more embodiments, the feed stream 101 may comprise one or more hydrocarbons. As described herein, the feed stream 101 may be passed into the reactor 110. In one or more embodiments, the one or more hydrocarbons may comprise one or more of ethane, propane, butane, or ethylbenzene. According to one or more embodiments, the one or more hydrocarbons may comprise at least 50 wt. %, at least 60 wt. %, at least 70 wt. %, at least 80 wt. %, at least 90 wt. %, at least 95 wt. % or even at least 99 wt. % of any of ethane. In additional embodiments, the one or more hydrocarbons may comprise at least 50 wt. %, at least 60 wt. %, at least 70 wt. %, at least 80 wt. %, at least 90 wt. %, at least 95 wt. % or even at least 99 wt. % of propane. In additional embodiments, the one or more hydrocarbons may comprise at least 50 wt. %, at least 60 wt. %, at least 70 wt. %, at least 80 wt. %, at least 90 wt. %, at least 95 wt. % or even at least 99 wt. % of butane. In additional embodiments, the one or more hydrocarbons may comprise at least 50 wt. %, at least 60 wt. %, at least 70 wt. %, at least 80 wt. %, at least 90 wt. %, at least 95 wt. % or even at least 99 wt. % of ethylbenzene. In additional embodiments, the one or more hydrocarbons may comprise at least 50 wt. %, at least 60 wt. %, at least 70 wt. %, at least 80 wt. %, at least 90 wt. %, at least 95 wt. % or even at least 99 wt. % of the sum of ethane, propane, butane, and ethylbenzene.

[0057] According to embodiments, the oxygen carrier material may be passed to the reactor 110 in an oxygen-rich state. In the reactor 110, the one or more hydrocarbons of the feed stream 101 may be dehydrogenated to form hydrogen (i.e., gas phase H2) and one or more olefinic compounds. According to embodiments, at least a portion of the hydrogen may be reacted with oxygen from the oxygen carrier material to form water. Reacting the hydrogen with oxygen from the oxygen carrier material may reduce the oxygen carrier material and convert it to an oxygendiminished state. As described herein, the oxygen-rich state of the oxygen carrier material has a greater amount of oxygen than the oxygen-diminished state of the oxygen carrier material. However, it should be understood that some oxygen may still be contained in the oxygendiminished state oxygen carrier material.

[0058] According to some embodiments, the dehydrogenation reaction in the reactor 110 may be thermally driven (i.e., non-catalytic) wherein, in such embodiments, a dehydrogenation catalyst is not utilized in the reactor 110. While the temperature of the reactor 110 may vary, in some embodiments, the reactor 110 may operate at a temperature of from 600 °C to 850 °C, which maybe appropriate to promote thermal dehydrogenation. In additional embodiments, a dehydrogenation catalyst may be utilized to promote dehydrogenation in the reactor 110. The dehydrogenation catalyst may be passed along with the oxygen carrier material and cycled between the reactor 110 and the regeneration unit 120. In embodiments where a dehydrogenation catalyst is utilized, temperatures of from 600 °C to 850 °C may also be utilized. Suitable dehydrogenation catalysts include, without limitation, those including platinum, platinum and gallium, platinum and tin, or chromium. For example, suitable catalysts are described in Chem. Rev. 2014, 114, 20, 10613-10653, which is incorporated herein by reference in its entirety and U.S. Pat. No. 8,669,406, which is incorporated herein by reference in its entirety.

[0059] The one or more olefinic compounds produced in the reactor 110, as well as unconverted hydrocarbons, water, and unconverted hydrogen may exit the reactor 110 via product stream 102. In one or more embodiments, the olefinic compounds may comprise one or more of ethylene, propylene, butylene, or styrene. The term butylene includes any isomers of butylene, such as a- butylene, cis-P-butylene, trans-P-butylene, and isobutylene. In some embodiments, the olefin- containing effluent may comprise at least 20 wt. %, at least 30 wt. %, at least 40 wt. %, at least 50 wt. %, or even at least 60 wt. % of ethylene. In additional embodiments, the olefin-containing effluent may comprise at least 20 wt. %, at least 30 wt. %, at least 40 wt. %, at least 50 wt. %, or even at least 60 wt. % of propylene. In additional embodiments, the olefin-containing effluent may comprise at least 20 wt. %, at least 30 wt. %, at least 40 wt. %, at least 50 wt. %, or even at least 60 wt. % of butylene. In additional embodiments, the olefin-containing effluent may comprise at least 20 wt. %, at least 30 wt. %, at least 40 wt. %, at least 50 wt. %, or even at least 60 wt. % of styrene. In additional embodiments, the olefin-containing effluent may comprise at least 20 wt. %, at least 30 wt. %, at least 40 wt. %, at least 50 wt. %, or even at least 60 wt. % of the sum of one or more of ethylene, propylene, butylene, and styrene. The product stream 102 may further comprise unreacted components of the feed stream 101, as well as other reaction products that are not considered olefinic compounds. The olefinic compounds may be separated from unreacted components in subsequent separation steps.

[0060] As described herein, in the reactor 110, the one or more hydrocarbons, such as ethane, may be dehydrogenated to produce hydrogen, and that hydrogen may be reacted with oxygen via a combustion reaction to form water. The oxygen is supplied by the oxygen carrier material, and the reaction of the hydrogen into water pushes the dehydrogenation reaction equilibrium towards the products, such as ethylene. In such embodiments, it is advantageous that the oxygen carriermaterial promotes the combustion of hydrogen over reactions with hydrocarbons present in the reactor 110. Such hydrocarbons may include the feed hydrocarbons such as ethane as well as product olefinic compounds, such as ethylene. Reaction of these hydrocarbons with the oxygen from the oxygen carrier material may undesirably form carbon monoxide and / or carbon dioxide. Carbon dioxide and carbon monoxide in the product stream 102 may cause several issues, such as difficulty in separating such components from other compounds in the product stream 102 as well as the potential emission of carbon dioxide into the environment or need to sequester such carbon dioxide. For example, carbon monoxide may be an undesirable inhibitor in certain downstream unit operations like acetylene hydrogenation reactors. With this in mind, it has been found that the presently disclosed oxygen carrier materials may have relatively high selectivity for promoting hydrogen combustion to form water as compared with selectivity for promoting the undesirable combustion of hydrocarbons with feed alkanes such as ethane and / or product olefinic compounds such as ethylene.

[0061] According to one or more embodiments, and as is described herein, the hydrogen formed by the dehydrogenation reaction is gaseous H2, which reacts with oxygen from the oxygen carrier material. This is in contrast to some other reaction mechanisms, such as oxidative dehydrogenation, where hydrogen is not formed. Rather, in such oxidative dehydrogenation reactions, alkanes are processed to olefins in a single reaction step where hydrogen (H2) is not formed as an intermediary. This concept is described in detail in, for example, “Oxidative Dehydrogenation of Ethane: Common Principles and Mechanistic Aspects,” Gartner et al. ChemCatChem 2013, 5, 3196-3217.

[0062] As described herein, the oxygen carrier material is passed into the reactor 110 and subsequently out of the reactor 110. Referring again to FIG. 1, in some embodiments, the oxygen carrier material is cycled between the reactor 110 and a regeneration unit 120. The oxygen carrier material may pass from the reactor 110 to the regeneration unit 120 via stream 103 and be passed from the regeneration unit 120 back to the reactor 110 via stream 104, and be continuously looped. In general, the oxygen carrier material may enter the reactor 110 in an oxygen-rich state, lose some or all oxygen atoms in the reactor 110 (to combust with hydrogen gas), and exit the reactor 110 in an oxygen-diminished state via stream 103. The oxygen carrier material in the oxygendiminished state may be passed to the regeneration unit 120 where it is exposed to oxygen and regenerated into its oxygen-rich state. This oxygen carrier material in the oxygen-rich state may be passed from the regeneration unit 120 via stream 104 back to the reactor 110.

[0063] According to one or more embodiments, in the regeneration unit 120, the oxygen carrier material may be exposed to oxygen, such as by exposure to air, oxygen enriched air, or even pure oxygen. This exposure allows the oxygen carrier material to be replenished with oxygen. Additionally, in the regeneration unit 120, a fuel gas may be combusted in order to heat the oxygen carrier material. This heat may be the main source of heat to maintain temperatures in the reactor 110, which is using heat by the dehydrogenation reaction. The fuel gas may comprise a variety of combustible compounds, such as hydrogen, methane, ethane, propane, etc. In some embodiments, methane may be the primary constituent of the fuel gas. In embodiments, the regeneration unit 120 may operate at elevated temperatures, such as from 600 °C to 900 °C, or temperatures that would be sufficient to heat the oxygen carrier materials to a temperature such that their heat can be utilized in the reactor 110 to drive the dehydrogenation reaction.

[0064] As described herein, a fuel gas, such as one comprising methane, may be combusted in the regeneration unit 120. It has been discovered that the composition of the oxygen carrier material may affect the fuel gas combustion rate, according to some embodiments. As such, it is undesirable to utilize an oxygen carrier material that has a composition that will slow the combustion of hydrocarbons. This is particularly a problem, since the oxygen carrier materials may be chosen such that they promote combustion of hydrogen but not alkanes and / or alkenes in the reactor 110. However, it has been observed that the presently disclosed oxygen carrier materials, according to one or more embodiments, may have acceptable levels of promotion of alkane combustion, such as methane combustion, in the regeneration unit 120 while having good selectivity for hydrogen combustion over ethane combustion in the reactor 110.

[0065] In some embodiments the oxygen-rich state oxygen carrier material may be partially reduced before being passed to the reactor 110. This may include exposing the oxygen carrier material in stream 104 to a reducing gas such as H2 and / or methane. Such treatment may allow for removal of some oxygen from the lattice of the oxygen carrier material. However, the amount of remaining oxygen is still suitable for supplying oxygen to the reactor 110 for combustion of hydrogen, as disclosed herein.

[0066] The present disclosure includes numerous aspects, including aspects 1-15 described herein.

[0067] Aspect 1. An oxygen carrier material comprising a first composition, wherein at least 95 wt.% of the first composition consists of: from 0.001 parts by mole to 0.999 parts by mole of iron; from 0.001 parts by mole to 0.999 parts by mole of the combination of one or more ofmanganese, cerium, cobalt, copper, nickel, or zinc, wherein the sum of the parts by mole of the iron and the parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc is equal to 1 part by mole; from 0.04 parts by mole to 0.8 parts by mole of one or more alkali metals; from 0.02 parts by mole to 0.4 parts by mole of tungsten; from 0 parts by mole to 3 parts by mole of titanium; and from 1 parts by mole to 10 parts by mole of oxygen.

[0068] Aspect 2. The oxygen carrier material of any previous aspect, wherein the first composition comprises manganese.

[0069] Aspect s. The oxygen carrier material of any previous aspect, wherein the first composition comprises cerium.

[0070] Aspect 4. The oxygen carrier material of any previous aspect, wherein the first composition comprises cobalt.

[0071] Aspect s. The oxygen carrier material of any previous aspect, wherein the first composition comprises copper.

[0072] Aspect 6. The oxygen carrier material of any previous aspect, wherein the first composition comprises nickel.

[0073] Aspect 7. The oxygen carrier material of any previous aspect, wherein the first composition comprises zinc.

[0074] Aspect 8. The oxygen carrier material of any previous aspect, wherein the first composition comprises titanium.

[0075] Aspect 9. The oxygen carrier material of any previous aspect, wherein at least 99 wt.% of the first composition consists of: from 0.001 parts by mole to 0.999 parts by mole of iron; from 0.001 parts by mole to 0.999 parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc, wherein the sum of the parts by mole of the iron and the parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc is equal to 1 part by mole; from 0.04 parts by mole to 0.8 parts by mole of one or more alkali metals; from 0.02 parts by mole to 0.4 parts by mole of tungsten; from 0 parts by mole to 3 parts by mole of titanium; and from 1 parts by mole to 10 parts by mole of oxygen.

[0076] Aspect 10. The oxygen carrier material of any previous aspect, wherein the first composition consists of: from 0.001 parts by mole to 0.999 parts by mole of iron; from 0.001 parts by mole to 0.999 parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc, wherein the sum of the parts by mole of the iron and the parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc is equal to1 part by mole; from 0.04 parts by mole to 0.8 parts by mole of one or more alkali metals; from 0.02 parts by mole to 0.4 parts by mole of tungsten; from 0 parts by mole to 3 parts by mole of titanium; and from 1 parts by mole to 10 parts by mole of oxygen.

[0077] Aspect 11. The oxygen carrier material of aspect 1, further comprising one or more additional materials chosen from oxides of silicon, aluminum, calcium, magnesium, zirconium, niobium, or combinations thereof.

[0078] Aspect 12 The oxygen carrier material of aspect 11, wherein at least 99 wt.% of the oxygen carrier material is the first composition and the one or more additional materials.

[0079] Aspect 13. A method for making the oxygen carrier material of any previous aspect.

[0080] Aspect 14. The method of aspect 13, wherein the method comprises wet or dry impregnation.

[0081] Aspect 15. The method of aspect 13, wherein the method comprises solid state synthesis.EXAMPLES

[0082] The various embodiments of the present disclosure will be further clarified by the following examples. The examples are illustrative in nature and should not be understood to limit the subject matter of the present disclosure.

[0083] Example 1 - Sample Preparation

[0084] Comparative Sample A was prepared by first weighing a stoichiometric amount of Fe2O3, TiCh (Noah Technologies Corporation, anatase) and WO3 (Sigma- Aldrich, < 25 pm) in a mortar. The dry powders were first ground with a pestle for 5 min. The powders were then shaken for 1 min in a separate container and replaced back into the mortar. The grinding and shaking were repeated for two times (for a total of 10 min of grinding and 2 min of shaking). Separately, a stoichiometric amount of K2CO3 powders were dissolved in ~ 10 mL of deionized H2O. The mixed metal oxide powders were ground and pasted for 5 min after introducing the alkali solution. The paste was then transferred to an alumina crucible and dried for at least 2 hours at 120 °C in air. The dried mixture was calcined in air at 950 °C for 6 hours.

[0085] Comparative Sample B was prepared by first combining a stoichiometric amount of Fe2O3 (Noah Technologies Corporation) with TiCh (Sigma- Aldrich, 21 nanometer nanopowder) weighted in a mortar. The dry powders were ground with a pestle for 5 minutes. The powders were shaken in a separate container for 1 minute and then returned to the mortar. The grinding and shaking steps were repeated twice, for a total of 10 minutes of grinding and 2 minutes ofshaking. Subsequently, 5 to 10 milliliters (mL) of deionized water was added to the mortar and the mixture was ground into a paste for 5 minutes. The paste was transferred to an alumina crucible and dried for at least 2 hours at 120 °C in air. The dried mixture was then calcined in air at 950 °C for 24 hours.

[0086] Sample 1 was prepared by first weighing a stoichiometric amount of Fe2O3, MnTTi (Elkem, MicroMax EU), TiCh (Noah Technologies Corporation, anatase) and WO3 in a mortar. The dry powders were ground with a pestle for 5 min. The powders were then shaken for 1 min in a separate container and replaced back into the mortar. The grinding and shaking were repeated for two times (for a total of 10 min of grinding and 2 min of shaking). Separately, a stoichiometric amount of K2CO3 powders were dissolved in ~ 10 mL of deionized H2O. The mixed metal oxide powders were ground and pasted for 5 min after introducing the alkali solution. The paste was then transferred to an alumina crucible and dried for at least 2 hours at 120 °C in air. The dried mixture was calcined in air at 950 °C for 6 hours.

[0087] Sample 2 was prepared in the same manner as Sample 1 with K2CO3, WO3, Fe2O3, CeCh (Sigma- Aldrich, nanopowder, < 50 nm) and TiCh (Noah Technologies Corporation, anatase).

[0088] Sample 3 was prepared in the same manner as Sample 1 with with K2CO3, WO3, Fe2O3, CO3O4 (Sigma- Aldrich, < 10 pm) and TiCh lNoah Technologies Corporation, anatase).

[0089] Sample 4 was prepared in the same manner as Sample 1 with K2CO3, WO3, Fe2O3, CuO (Sigma- Aldrich, < 10 pm) and TiCh (Noah Technologies Corporation, anatase).

[0090] Sample 5 was prepared in the same manner as Sample 1 with K2CO3, WO3, Fe2O3, ZnO (Sigma- Aldrich, nanopowder, < 100 nm) and TiCh iNoah Technologies Corporation, anatase).

[0091] Samples 6 and 7 were prepared in the same manner as Sample 1 with K2CO3, WO3, Fe2O3, MmC and TiCh (Noah Technologies Corporation, anatase) in a different stoichiometry.

[0092] Sample 8 was prepared in the same manner as Sample 2 with K2CO3, WO3, Fe2O3, CeCh and TiCh (Noah Technologies Corporation, anatase) in a different stoichiometry.

[0093] Sample 9 was prepared in the same manner as Sample 1 with K2CO3, WO3, Fe2O3, NiO (ThermoScientific) and TiCh (Noah Technologies Corporation, anatase).

[0094] Example 2 - Selective Hydrogen Combustion and Methane Combustion Performance

[0095] Testing of the oxygen carriers was performed in a fixed bed laboratory reactor. A 0.5 gram (g) portion of the sample was loaded into a 0.5 inch outer diameter (OD) quartz bulb connected to a 0.25 inch outer diameter (OD) quartz tubing. The sample bed was supported on a pill of quartz wool and a layer of 0.5 to 1.0 mm quartz chips. The reactor was installed into aclamshell furnace and a flow of nitrogen at 40 standard cubic centimeters (seem) was introduced through the reactor tube. The reactor was then heated under 40 seem of air flow, from room temperature to 780 °C. The oxygen carrying materials were subjected to several cyclic sequences. Each cycle included ethane dehydrogenation, a first regeneration in air, fuel (methane) combustion, then a second regeneration in air with inert nitrogen purging in the reactor tube between reduction and oxidation pulses. The ethane dehydrogenation step was done at a weight hourly space velocity (WHSV) of 5.3 hr'1. Specifically, 40 seem of a gas mixture containing 90 mol% ethane and 10 mol% helium was fed through the reactor for 60 seconds while the reactor was held at 780 °C. Analysis of the product gas composition was taken at 30 seconds into the dehydrogenation reaction pulse (halfway through). The reactor was then heated under 40 seem of nitrogen flow from 780 °C to 850 °C. During the first regeneration in air step, 40 seem of air was fed through the reactor for 2 minutes at 850 °C. The fuel (methane) combustion step was performed at a WHSV of 0.079 hr'1. Specifically, 40 seem of a gas mixture containing 2.5 mol% methane, 9 mol% oxygen in balance nitrogen was fed through the reactor for 180 seconds while the reactor was held at 850 °C. Analysis of the product gas composition was taken at 60 seconds into the fuel combustion pulse. Finally, 40 seem of air was fed through the reactor for 4 minutes to conduct the second air regeneration step at 850 °C, then the reactor was cooled down to 780 °C under 40 seem of nitrogen flow. The product gas composition was analyzed by a Siemens Maxim Process Gas Chromatograph. For each oxygen carrying materials, multiple replicate reductionoxidation cycles were performed. Ethane conversion, ethylene selectivity, COXselectivity, hydrogemethylene ratio, and methane conversion are reported at cycle 50.

[0096] Carbon-based ethane conversion and product selectivities were calculated using the following equations, where [X] corresponds to the molar fraction.Table 1: Selective hydrogen combustion and methane combustion performance of materials evaluated using the method of Example 2

[0097] As shown in Table 1, all samples with the presence of an additional transition metal (M) (z.e., Samples 1-9) have greater CH4 conversion than samples without an additional metal (z.e., Comparative Samples A and B). For example, Comparative Sample A with no additional metal has a CH4 conversion of 77.6% and Sample 4 with Cuo.i has a CH4 conversion of 95.7%, indicating that the presence of an additional metal improves methane combustion performance in oxygencarrier materials.

[0098] Additionally, samples with the additional metal are shown to have an improved CH4 conversion while also maintaining or even improving C2H4 selectivity, COXselectivity, and / or H2 / C2H4 ratio, indicating that these oxygen-carrier materials work well for selective hydrogen combustion. For example, Comparative Sample A with no additional metal has a CH4 conversion of 77.6% and Sample 5, which is identical except for the addition of Zno.i, has a CH4 conversion of 84.3%. Further, Comparative Sample A has a C2H4 selectivity of 94.4%, COXselectivity of 1.2%, and H2 / C2H4 ratio of 0.15 and Sample 5 has a C2H4 selectivity of 94.5%, COXselectivity of 0.7%, and H2 / C2H4 ratio of 0.09, indicating that the presence of an additional metal also generally maintains and / or improves selective hydrogen combustion of the oxygen-carrier material.

[0099] Therefore, Table 1 indicates that the presence of the additional metal in oxygen-carrier materials as a partial substitution for iron results in an improvement in CF conversion while maintaining effectiveness of selective hydrogen combustion as compared to oxygen-carrier materials without an additional metal.

[0100] It will be apparent to those skilled in the art that various modifications and variations can be made to the presently disclosed technology without departing from the spirit and scope of the technology. Since modifications combinations, sub-combinations and variations of the disclosed embodiments incorporating the spirit and substance of the presently disclosed technology may occur to persons skilled in the art, the technology should be construed to include everything within the scope of the appended claims and their equivalents. Additionally, although some aspects of the present disclosure may be identified herein as preferred or particularly advantageous, it is contemplated that the present disclosure is not limited to these aspects.

[0101] It is noted that the various details described in this disclosure should not be taken to imply that these details relate to elements that are essential components of the various embodiments described in this disclosure, even in cases where a particular element is illustrated in each of the drawings that accompany the present description. Unless specifically identified as such, no feature disclosed and described herein should be construed as “essential”. Contemplated embodiments of the present technology include those that include some or all of the features of the appended claims.

[0102] For the purposes of describing and defining the present disclosure it is noted that the term “about” are utilized in this disclosure to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. The term “about” are also utilized in this disclosure to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.

[0103] In relevant cases, where a composition is described as “comprising” one or more elements, embodiments of that composition “consisting of’ or “consisting essentially of’ those one or more elements is contemplated herein.

[0104] It should be appreciated that compositional ranges of a chemical constituent in a stream or in a reactor should be appreciated as containing, in some embodiments, a mixture of isomers of that constituent. For example, a compositional range specifying butene may include a mixture of various isomers of butene. It should be appreciated that the examples supply compositional ranges for various streams, and that the total amount of isomers of a particular chemical composition can constitute a range.

[0105] It is noted that one or more of the following claims and the detailed description utilize the terms “where” or “wherein” as a transitional phrase. For the purposes of defining the presenttechnology, it is noted that this term is introduced in the claims as an open-ended transitional phrase that is used to introduce a recitation of a series of characteristics of the structure and should be interpreted in like manner as the more commonly used open-ended preamble term “comprising.”

[0106] It should be understood that any two quantitative values assigned to a property may constitute a range of that property, and all combinations of ranges formed from all stated quantitative values of a given property are contemplated in this disclosure. Where multiple ranges for a quantitative value are provided, these ranges may be combined to form a broader range, which is contemplated in the embodiments described herein.

[0107] As would be understood in the context of the term as used herein, the term “passing” may include directly passing a substance between two portions of the disclosed system and, in some other instances, to mean indirectly passing a substance between two portions of the disclosed system. For example, indirect passing may include steps where the named substance passes through an intermediate operations unit, valve, sensor, etc.

Claims

CLAIMS1. An oxygen carrier material comprising a first composition, wherein at least 95 wt.% of the first composition consists of: from 0.001 parts by mole to 0.999 parts by mole of iron; from 0.001 parts by mole to 0.999 parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc, wherein the sum of the parts by mole of the iron and the parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc is equal to 1 part by mole; from 0.04 parts by mole to 0.8 parts by mole of one or more alkali metals; from 0.02 parts by mole to 0.4 parts by mole of tungsten; from 0 parts by mole to 3 parts by mole of titanium; and from 1 parts by mole to 10 parts by mole of oxygen.

2. The oxygen carrier material of any previous claim, wherein the first composition comprises manganese.

3. The oxygen carrier material of any previous claim, wherein the first composition comprises cerium.

4. The oxygen carrier material of any previous claim, wherein the first composition comprises cobalt.

5. The oxygen carrier material of any previous claim, wherein the first composition comprises copper.

6. The oxygen carrier material of any previous claim, wherein the first composition comprises nickel.

7. The oxygen carrier material of any previous claim, wherein the first composition comprises zinc.

8. The oxygen carrier material of any previous claim, wherein the first composition comprises titanium.

9. The oxygen carrier material of any previous claim, wherein at least 99 wt.% of the first composition consists of: from 0.001 parts by mole to 0.999 parts by mole of iron; from 0.001 parts by mole to 0.999 parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc, wherein the sum of the parts by mole of the iron and the parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc is equal to 1 part by mole; from 0.04 parts by mole to 0.8 parts by mole of one or more alkali metals; from 0.02 parts by mole to 0.4 parts by mole of tungsten; from 0 parts by mole to 3 parts by mole of titanium; and from 1 parts by mole to 10 parts by mole of oxygen.

10. The oxygen carrier material of any previous claim, wherein the first composition consistsfrom 0.001 parts by mole to 0.999 parts by mole of iron; from 0.001 parts by mole to 0.999 parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc, wherein the sum of the parts by mole of the iron and the parts by mole of the combination of one or more of manganese, cerium, cobalt, copper, nickel, or zinc is equal to 1 part by mole; from 0.04 parts by mole to 0.8 parts by mole of one or more alkali metals; from 0.02 parts by mole to 0.4 parts by mole of tungsten; from 0 parts by mole to 3 parts by mole of titanium; and from 1 parts by mole to 10 parts by mole of oxygen.

11. The oxygen carrier material of claim 1, further comprising one or more additional materials chosen from oxides of silicon, aluminum, calcium, magnesium, zirconium, niobium, or combinations thereof.12 The oxygen carrier material of claim 11, wherein at least 99 wt.% of the oxygen carrier material is the first composition and the one or more additional materials.

13. A method for making the oxygen carrier material of any previous claim.

14. The method of claim 13, wherein the method comprises wet or dry impregnation.

15. The method of claim 13, wherein the method comprises solid state synthesis.

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