Process for producing olefin compounds using an oxygen carrier material comprising iron and silicon dioxide

Abstract

Olefin compounds can be produced by a method that can include passing a feed stream into a reactor, where the feed stream includes one or more hydrocarbons; and passing an oxygen carrier material into the reactor. In the reactor, the one or more hydrocarbons can be dehydrogenated to form hydrogen gas and one or more olefin compounds, and at least a portion of the hydrogen gas can react with oxygen gas from the oxygen carrier material to produce water. At least 95 wt% of the oxygen carrier material can consist of: 1 mole fraction of iron; 0 mole fraction to 1 mole fraction of a combination of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium; 1 mole fraction to 20 mole fraction of silicon dioxide; and 1 mole fraction to 3 mole fraction of oxygen gas not included in the silicon dioxide.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 595,979, filed November 3, 2023, the contents of which are incorporated herein by reference. Technical Field

[0003] The embodiments disclosed herein generally relate to chemical processing, and specifically to chemical processing for the production of olefin materials. Background Technology

[0004] Olefin compounds, such as light olefins (e.g., ethylene, butene, and propylene), can be used as base materials to produce a wide variety of materials, such as polyethylene, polypropylene, isopropanol, and acrylic acid, which can be used in, for example, packaging, construction, and textiles. As a result of this utility, there is a global demand for light olefins. Suitable processes for producing light olefins generally depend on the given chemical feedstock and include those utilizing fluidized bed catalysts. For example, light olefins can be formed by the catalytic dehydrogenation of alkanes in a fluidized bed reactor. However, there is a need to improve the methods for preparing light olefins. Summary of the Invention

[0005] There is a persistent need for methods for producing olefin compounds. This document describes a method for producing olefin compounds by means of a process that typically includes the formation of olefin compounds through the dehydrogenation of hydrocarbons, such as alkanes. In such embodiments, an oxygen carrier material can be utilized, which supplies oxygen to burn hydrogen formed by the dehydrogenation reaction. Burning hydrogen typically shifts the dehydrogenation equilibrium toward the products (hydrogen and olefin compounds). It has been found that certain oxygen carrier materials described herein are well-suited for this process due to their relatively high selectivity for burning hydrogen compared to burning hydrocarbons. In particular, oxygen carrier materials comprising at least iron, oxygen, and silica, as described herein, can exhibit this selectivity and are well-suited for the methods described herein. The use of silica may result in enhanced selectivity for hydrogen combustion, unlike the combustion of alkanes and / or alkenes, compared to other known binder materials.

[0006] According to one or more embodiments of this disclosure, olefin compounds can be produced by a method comprising: passing a feed stream into a reactor, wherein the feed stream contains one or more hydrocarbons; and passing an oxygen carrier material into the reactor. In the reactor, one or more hydrocarbons can be dehydrogenated to form hydrogen and one or more olefin compounds, and at least a portion of the hydrogen can react with oxygen from the oxygen carrier material to produce water. At least 95% by weight of the oxygen carrier material may consist of: 1 mole of iron; 0 to 1 mole of one or more combinations of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium; 1 to 20 mole of silica; and 1 to 3 mole of oxygen not contained in silica.

[0007] Additional features and advantages of this disclosure will be set forth in the detailed description below, and will be partly apparent from the description or by practice of the embodiments described herein, including the detailed description below, the claims, and the drawings. Attached Figure Description

[0008] The following detailed description of specific embodiments of this disclosure is best understood in conjunction with the following drawings, in which similar reference numerals indicate similar structures and in the drawings:

[0009] Figure 1 This is a schematic diagram of a reactor system suitable for use with an oxygen carrier material, according to one or more embodiments described herein.

[0010] Additional features and advantages of this disclosure will be set forth in the detailed description below, and will be partly apparent from the description or by practice of the embodiments described herein, including the detailed description below, the claims, and the drawings.

[0011] It should 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 characteristics of the claimed subject matter. Drawings are included to provide a further understanding of the various embodiments, and these drawings are incorporated in and form part of this specification. The drawings illustrate the various embodiments described herein and, together with the specification, explain the principles and operation of the claimed subject matter. Detailed Implementation

[0012] Specific embodiments of this application will now be described. However, the technical aspects of this application may be implemented in different forms and should not be construed as limited to the embodiments set forth in this detailed description.

[0013] Generally, various embodiments of methods for producing olefin compounds are described in this disclosure. According to one or more embodiments of this disclosure, the methods for producing olefin compounds utilize oxygen-carrying materials (sometimes simply referred to herein as "oxygen carriers"). For example, these processes may utilize oxygen-carrying materials comprising at least iron, oxygen, silicon dioxide, and optionally one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium.

[0014] As used herein, the term "olefin compound" refers to a hydrocarbon having one or more carbon-carbon double bonds, other than the formal double bonds found in aromatic compounds. For example, ethylene and styrene are olefin compounds, but ethylbenzene would not be an olefin compound because the only double bond present in ethylbenzene is a formal double bond that exists as part of an aromatic structure.

[0015] Now for reference Figure 1 The diagram illustrates a reactor system 100 that can be used with the methods disclosed herein, but other reactor systems that would otherwise be suitable for the methods disclosed herein are contemplated. Figure 1 It is a simplified system, and other systems are envisioned. Additionally, in Figure 1 In this document, various reactor types are envisioned as potentially suitable for the methods described herein. For example, the oxygen carrier material of this disclosure can be used in the systems and methods 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 herein by reference in their entirety. These disclosed technical aspects may be further described herein with respect to... Figure 1 The methods and systems described. Additionally, it should be noted that... Figure 1 The indicated steps should not be construed as necessary steps, especially in light of the methods in the appended claims.

[0016] Still referencing Figure 1The 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. Typically, a feed stream 101 may be fed into the reactor 110 and processed in the reactor 110 to form a product stream 102 comprising one or more olefin compounds. As detailed herein, according to one or more embodiments, an oxygen carrier material may be circulated between the reactor 110 and the regeneration unit 120, wherein the oxygen carrier material enters the reactor 110 in an oxygen-enriched state, is supplied with oxygen in the reactor 110, leaves the reactor 110 in an oxygen-deficient state, and may be regenerated in the regeneration unit 120 to an oxygen-enriched state.

[0017] In one or more embodiments, feed stream 101 may contain one or more hydrocarbons. As described herein, feed stream 101 may be fed into reactor 110. In one or more embodiments, the one or more hydrocarbons may include one or more of ethane, propane, butane, or ethylbenzene. According to one or more embodiments, the one or more hydrocarbons may contain 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 ethane. In another embodiment, the one or more hydrocarbons may contain 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 another embodiment, the one or more hydrocarbons may contain 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 another embodiment, one or more hydrocarbons may contain at least 50% by weight, at least 60% by weight, at least 70% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, or even at least 99% by weight of ethylbenzene. In another embodiment, one or more hydrocarbons may contain at least 50% by weight, at least 60% by weight, at least 70% by weight, at least 80% by weight, at least 90% by weight, at least 95% by weight, or even at least 99% by weight of the sum of ethane, propane, butane, and ethylbenzene.

[0018] According to the embodiment, the oxygen carrier material can be transferred to reactor 110 in an oxygen-enriched state. In reactor 110, one or more hydrocarbons in the feed stream 101 can be dehydrogenated to form hydrogen (i.e., gaseous H2) and one or more olefin compounds. According to the embodiment, at least a portion of the hydrogen can react with oxygen from the oxygen carrier material to form water. Reacting hydrogen with oxygen from the oxygen carrier material reduces the oxygen carrier material and converts it to an oxygen-deficient state. As described herein, the oxygen-enriched state of the oxygen carrier material has a greater amount of oxygen than the oxygen-deficient state of the oxygen carrier material. However, it should be understood that some oxygen may still be contained within the oxygen carrier material in an oxygen-deficient state.

[0019] According to some embodiments, the dehydrogenation reaction in reactor 110 can be thermally driven (i.e., non-catalytic), wherein in such embodiments, no dehydrogenation catalyst is used in reactor 110. While the temperature of reactor 110 can vary, in some embodiments, reactor 110 can be operated at temperatures from 600°C to 850°C, which may be suitable for promoting thermal dehydrogenation. In other embodiments, a dehydrogenation catalyst can be used to promote dehydrogenation in reactor 110. The dehydrogenation catalyst can be transferred together with the oxygen support material and circulated between reactor 110 and regeneration unit 120. Temperatures from 600°C to 850°C can also be used in embodiments where a dehydrogenation catalyst is used. Suitable dehydrogenation catalysts include, but are not limited to, those comprising platinum, platinum and gallium, platinum and tin, or chromium. For example, suitable catalysts are described in Chem. Rev. 2014, 114, 20,10613–10653 (the entire contents of which are incorporated herein by reference) and U.S. Patent No. 8,669,406 (the entire contents of which are incorporated herein by reference).

[0020] One or more olefin compounds produced in reactor 110, along with unconverted hydrocarbons, water, and unconverted hydrogen, may exit reactor 110 via product stream 102. In one or more embodiments, the olefin compounds may include one or more of ethylene, propylene, butene, or styrene. The term butene includes any butene isomer, such as α-butene, cis-β-butene, trans-β-butene, and isobutene. In some embodiments, the olefin-containing effluent may contain 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 other embodiments, the olefin-containing effluent may contain 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 other embodiments, the olefin-containing effluent may contain at least 20 wt%, at least 30 wt%, at least 40 wt%, at least 50 wt%, or even at least 60 wt% of butene. In another embodiment, the olefin-containing effluent may contain at least 20% by weight, at least 30% by weight, at least 40% by weight, at least 50% by weight, or even at least 60% by weight of styrene. In another embodiment, the olefin-containing effluent may contain at least 20% by weight, at least 30% by weight, at least 40% by weight, at least 50% by weight, or even at least 60% by weight of one or more of ethylene, propylene, butene, and styrene. Product stream 102 may also contain unreacted components from feed stream 101 and other reaction products that are not considered olefin compounds. Olefin compounds may be separated from the unreacted components in a subsequent separation step.

[0021] As described herein, in reactor 110, one or more hydrocarbons (such as ethane) can be dehydrogenated to produce hydrogen, and the hydrogen can react with oxygen via a combustion reaction to form water. Oxygen is provided by an oxygen carrier material, and the reaction of hydrogen to water pushes the dehydrogenation equilibrium toward the product (such as ethylene). In such embodiments, it is advantageous that the oxygen carrier material promotes the combustion of hydrogen beyond its reaction with hydrocarbons present in reactor 110. Such hydrocarbons may include feed hydrocarbons (such as ethane) and product olefin compounds (such as ethylene). The reaction of these hydrocarbons with oxygen from the oxygen carrier material may undesirably form carbon monoxide and / or carbon dioxide. Carbon dioxide and carbon monoxide in product stream 102 can cause several problems, such as difficulty in separating such components from other compounds in product stream 102, and the potential release of carbon dioxide into the environment or the need to isolate such carbon dioxide. For example, carbon monoxide may be an undesirable inhibitor in certain downstream unit operations (such as acetylene hydrogenation reactors). In this regard, it has been found that the oxygen carrier materials disclosed in this invention can have relatively high selectivity for promoting the combustion of hydrogen to form water, compared to selectivity for promoting the undesirable combustion of hydrocarbons with feed alkanes (such as ethane) and / or product olefin compounds (such as ethylene).

[0022] According to one or more embodiments, and as described herein, the hydrogen formed by the dehydrogenation reaction is gaseous H2, which reacts with oxygen from the oxygen-carrying material. This contrasts with some other reaction mechanisms, such as oxidative dehydrogenation, in which no hydrogen is formed. Instead, in this type of oxidative dehydrogenation reaction, the alkane is processed into an olefin in a single reaction step, in which no hydrogen (H2) is formed as an intermediate. This concept is described in detail, for example, in Gartner et al., “Oxidative Dehydrogenation of Ethane: Common Principles and Mechanistic Aspects” (ChemCatChem 2013, 5, 3196-3217).

[0023] As described herein, oxygen carrier material is transferred into reactor 110 and subsequently transferred out of reactor 110. See again Figure 1 In some embodiments, the oxygen carrier material circulates between reactor 110 and regeneration unit 120. The oxygen carrier material can be transferred from reactor 110 to regeneration unit 120 via stream 103 and returned from regeneration unit 120 to reactor 110 via stream 104, and this circulation is continuous. Generally, the oxygen carrier material enters reactor 110 in an oxygen-enriched state, loses some or all of its oxygen atoms (to burn with hydrogen) in reactor 110, and leaves reactor 110 in an oxygen-deficient state via stream 103. The oxygen-deficient oxygen carrier material can be transferred to regeneration unit 120, where it is exposed to oxygen and regenerated into its oxygen-enriched state. The oxygen-enriched oxygen carrier material can then be transferred back from regeneration unit 120 to reactor 110 via stream 104.

[0024] According to one or more embodiments, in regeneration unit 120, the oxygen carrier material may be exposed to oxygen, such as through exposure to air, oxygen-enriched air, or even pure oxygen. This exposure allows the oxygen carrier material to replenish oxygen. Additionally, in regeneration unit 120, fuel gas may be burned to heat the oxygen carrier material. This heat may be the primary heat source for maintaining the temperature in reactor 110, which uses heat for the dehydrogenation reaction. The fuel gas may include a variety of combustible compounds, such as hydrogen, methane, ethane, propane, etc. In some embodiments, methane may be the main component of the fuel gas. In embodiments, regeneration unit 120 may operate at elevated temperatures, such as 600°C to 900°C or temperatures that would otherwise be sufficient to heat the oxygen carrier material to a level where their heat can be used to drive the dehydrogenation reaction in reactor 110.

[0025] As described herein, fuel gases (such as fuel gases containing methane) can be combusted in regeneration unit 120. According to some embodiments, it has been found that the composition of the oxygen carrier material can affect the combustion rate of the fuel gases. Therefore, it is undesirable to use oxygen carrier materials with compositions that would slow down hydrocarbon combustion. This is particularly problematic because oxygen carrier materials can be selected such that they promote the combustion of hydrogen in reactor 110 but not the combustion of alkanes and / or alkenes therein. However, it has been observed that, according to one or more embodiments, the oxygen carrier materials disclosed in this invention can have an acceptable level of alkane combustion (such as methane combustion) promotion in regeneration unit 120, while exhibiting good selectivity for hydrogen combustion relative to ethane combustion in reactor 110.

[0026] In some embodiments, the oxygen-enriched oxygen carrier material may be partially reduced before being passed to reactor 110. This may include exposing the oxygen carrier material in stream 104 to a reducing gas, such as H2 and / or methane. This treatment may allow some oxygen to be removed from the lattice of the oxygen carrier material. However, as disclosed herein, the amount of remaining oxygen is still suitable for supplying oxygen to reactor 110 for hydrogen combustion.

[0027] In the embodiments disclosed herein, the oxygen carrier material may have a specific composition. As described herein, at least 95% by weight of the oxygen carrier material may consist of iron, oxygen, silica, and optionally one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium. In one or more embodiments, the oxygen carrier material may comprise or consist of active materials that are generally conducive to oxygen carrying capacity of the oxygen carrier material described herein. As described below, such active materials may also affect fuel combustion during regeneration. Generally, and as described herein, materials other than silica may act as active materials. In one or more embodiments, silica may act as a binder. In some embodiments, the binder may not substantially contribute to the oxygen carrying and / or catalytic function of the oxygen carrier material. Binders generally enhance the physical properties of the oxygen carrier material. As described herein, silica may also contribute to the functionality of the oxygen carrier material in promoting the combustion of hydrogen over alkanes and / or alkenes in reactor 110.

[0028] As described herein, the relative amounts of the oxygen-supported material are described based on the relative amounts of atoms of each element contained in the oxygen-supported material. Furthermore, as described herein, the components of the oxygen-supported material can be described in amounts relative to other components. For example, components described herein are expressed in amounts described as "molar parts." As used herein, molar parts describe the molar ratio of one component to another and do not limit the total number or moles of a particular substituent. For example, iron may be present in an amount of 1 molar part, and oxygen may be present in amounts from 1 molar part to 3 molar parts, meaning that all compositions satisfying this ratio of iron atoms to oxygen atoms fall within the embodiments described herein, regardless of the original amounts of these components. Generally, and unless otherwise stated, where multiple elements or other materials are listed together in specific amounts, this refers to the sum of all such combinations of elements or other materials, even if it is not explicitly stated that the "sum" or "combination" of these elements refers to a specific amount.

[0029] Turning now to the oxygen carrier material, in one or more embodiments, 95% by weight of the oxygen carrier material may consist of: 1 mole of iron; 0 to 1 mole of one or more combinations of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium; 1 to 20 mole of silicon dioxide; and 1 to 3 mole of oxygen not contained in the silicon dioxide. For example, at least 96% by weight, at least 97% by weight, at least 98% by weight, at least 99% by weight, at least 99.5% by weight, or at least 99.9% by weight of the oxygen carrier material may consist of: 1 mole of iron; 0 to 1 mole of one or more combinations of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium; 1 to 20 mole of silicon dioxide; and 1 to 3 mole of oxygen not contained in the silicon dioxide.

[0030] In one or more embodiments, iron may be present in the oxygen carrier material, wherein iron is present in a relative amount of 1 mole part in the oxygen carrier material. The amounts of other components are generally compared to 1 mole part of iron. Without being bound by any particular theory, it is believed that iron can serve as a major component, which binds to and debindes with oxygen in redox reactions by changing its oxidation state.

[0031] In one or more embodiments, oxygen may be present in the oxygen carrier material in a relative amount of 1 to 3 moles, independent of oxygen in silica. The amount of oxygen may depend on the oxidation state of the oxygen carrier material, wherein more oxygen may be present in embodiments where the oxygen carrier material is storing oxygen atoms, and less oxygen may be present once such oxygen has been provided for the reaction and prior to regeneration. Generally, as described herein, the amount of oxygen can vary at different points in the process of forming olefins.

[0032] In some embodiments, oxygen may exist independently of oxygen in silica in the oxygen carrier material in a relative amount of less than or equal to 3 moles and at least 1.2 moles, at least 1.4 moles, at least 1.6 moles, at least 1.8 moles, at least 2 moles, at least 2.2 moles, at least 2.4 moles, at least 2.6 moles, or at least 2.8 moles.

[0033] In another embodiment, oxygen may exist independently of oxygen in silica in the oxygen carrier material in a relative amount of at least 1 mole and less than or equal to 2.8 moles, less than or equal to 2.6 moles, less than or equal to 2.4 moles, less than or equal to 2.2 moles, less than or equal to 2 moles, less than or equal to 1.8 moles, less than or equal to 1.6 moles, less than or equal to 1.4 moles, or less than or equal to 1.2 moles.

[0034] In another embodiment, oxygen may be present in the oxygen carrier material independently of oxygen in silica in a relative amount of 1 mol to 1.2 mol, 1.2 mol to 1.4 mol, 1.4 mol to 1.6 mol, 1.6 mol to 1.8 mol, 1.8 mol to 2 mol, 2 mol to 2.2 mol, 2.2 mol to 2.4 mol, 2.4 mol to 2.6 mol, 2.6 mol to 2.8 mol, 2.8 mol to 3 mol, or any combination of one or more of these ranges.

[0035] In one or more embodiments, silica (i.e., silicon dioxide) may be present in the oxygen carrier material in a relative amount of 1 to 20 moles. As described herein, silica can be used to enhance the physical properties of the oxygen carrier material, which allows the oxygen carrier to function for a longer period without wear due to mechanical damage. Furthermore, without being bound by theory, it is believed that the incorporation of silica can enhance the functionality of the oxygen carrier material by promoting the combustion of hydrogen that forms water, rather than the combustion of unfavorable alkanes and / or alkenes that form carbon dioxide and / or carbon monoxide. For example, an oxygen carrier material containing iron and silica may promote the combustion of hydrogen better than an oxygen carrier material containing iron and another binder. Other conventional binders include, but are not limited to, oxides of aluminum, calcium, magnesium, zirconium, niobium, or combinations thereof (including those containing silica, such as aluminosilicates). Other conventional binders are disclosed in "Progress in Chemical-Looping Combustion and Reforming technologies," *Progress in Energy and Combustion Science*, 38(2012) 215-282, and Liang-Shih Fan's "Chemical Looping Systems for Industrial Chemistry Conversions," published by WILEY Press in 2010. For example, in some embodiments, conventional binders not used by some implementers as described herein include alumina (α-phase, θ-phase, or γ-phase), CaAl... x O y MgAl2O4, zirconium oxide and inorganic clays (e.g., kaolin, other aluminum silicates).

[0036] In some embodiments, silica may be present in the oxygen carrier material in a relative amount of less than or equal to 20 moles and at least 3 moles, at least 5 moles, at least 7 moles, at least 9 moles, at least 11 moles, at least 13 moles, at least 15 moles, at least 17 moles, or at least 19 moles. In other embodiments, silica may be present in the oxygen carrier material in a relative amount of at least 1 mole and less than or equal to 18 moles, less than or equal to 16 moles, less than or equal to 14 moles, less than or equal to 12 moles, less than or equal to 10 moles, less than or equal to 8 moles, less than or equal to 6 moles, less than or equal to 4 moles, or less than or equal to 2 moles.

[0037] In another embodiment, silica may be present in the oxygen carrier material in a relative amount of 1 to 3 moles, 3 to 5 moles, 5 to 7 moles, 7 to 9 moles, 9 to 11 moles, 11 to 13 moles, 13 to 15 moles, 15 to 17 moles, 17 to 19 moles, 19 to 20 moles, or any combination of one or more of these ranges.

[0038] In one or more embodiments, the oxygen support material may optionally comprise one or more combinations of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium (sometimes referred to herein as "dopants," where "dopant" refers to the list of elements). That is, in some embodiments, combinations of one or more dopants may not be present in the oxygen support material. Without being bound by any particular theory, strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium are believed to be components that bind and debind with oxygen in redox reactions by altering their oxidation state. Furthermore, the incorporation of these dopants can enhance hydrogen combustion in reactor 110 relative to the undesirable combustion of alkanes and / or alkenes as described herein.

[0039] In one or more embodiments, one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium may be present in the oxygen support material in a relative amount of 0 to 1 mole. In some embodiments, one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium may be present in the oxygen support material in a relative amount of 0.001 to 1 mole.

[0040] In some embodiments, one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium may be present in the oxygen carrier material in a relative amount of less than or equal to 1 mole and at least 0.05 moles, at least 0.1 moles, at least 0.15 moles, at least 0.2 moles, at least 0.25 moles, at least 0.3 moles, at least 0.35 moles, at least 0.4 moles, at least 0.45 moles, at least 0.5 moles, at least 0.55 moles, at least 0.6 moles, at least 0.65 moles, at least 0.7 moles, at least 0.75 moles, at least 0.8 moles, at least 0.85 moles, at least 0.90 moles, or at least 0.95 moles.

[0041] In another embodiment, one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium may be present in the oxygen carrier material in a relative amount of at least 0.001 moles and less than or equal to 0.95 moles, less than or equal to 0.9 moles, less than or equal to 0.85 moles, less than or equal to 0.8 moles, less than or equal to 0.75 moles, less than or equal to 0.7 moles, less than or equal to 0.65 moles, less than or equal to 0.6 moles, less than or equal to 0.55 moles, less than or equal to 0.5 moles, less than or equal to 0.45 moles, less than or equal to 0.4 moles, less than or equal to 0.35 moles, less than or equal to 0.3 moles, less than or equal to 0.25 moles, less than or equal to 0.2 moles, less than or equal to 0.15 moles, less than or equal to 0.1 moles, or less than or equal to 0.05 moles.

[0042] In another embodiment, one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium may be present in the oxygen carrier material in relative amounts of 0 to 0.1 mol, 0.1 to 0.2 mol, 0.2 to 0.3 mol, 0.3 to 0.4 mol, 0.4 to 0.5 mol, 0.5 to 0.6 mol, 0.6 to 0.7 mol, 0.7 to 0.8 mol, 0.8 to 0.9 mol, 0.9 to 1 mol, or any combination of one or more of these ranges.

[0043] According to some embodiments, as described herein, any one, two, three, four, five, six, seven, eight, nine, or all ten of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium may be used. This document discloses embodiments in which one or more of these elements (e.g., one, two, three, four, ..., or all ten) are present within the scope of this disclosure. In some embodiments, one or more alkaline earth metals of strontium, calcium, or magnesium may be present in the oxygen-supporting material within any range described herein. In other embodiments, one or more lanthanide elements of lanthanum, cerium, praseodymium, neodymium, or samarium may be present in the oxygen-supporting material within the range described herein. In other embodiments, titanium may be present in the oxygen-supporting material within the range described herein.

[0044] According to one or more embodiments, the oxygen carrier material does not contain alkali metals such as lithium, sodium, potassium, rubidium, or cesium. It is believed that the oxygen carrier materials disclosed in this invention can function adequately without alkali metals, and some conventional embodiments may utilize alkali metals to improve the selectivity of hydrogen combustion relative to hydrocarbon combustion.

[0045] 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 50 µm to 300 µm, such as 50 µm to 250 µm, 50 µm to 200 µm, 50 µm to 150 µm, 50 µm to 100 µm, 100 µm to 300 µm, 100 µm to 250 µm, 100 µm to 200 µm, 100 µm to 150 µm, 150 µm to 300 µm, 150 µm to 250 µm, 150 µm to 200 µm, 200 µm to 300 µm, 200 µm to 250 µm, or 250 µm to 300 µm.

[0046] In some implementations, the oxygen carrier material may exhibit properties industrially known as “Geldart A” or “Geldart B” characteristics. According to D. Geldart, Gas Fluidization Technology, John Wiley & Sons (New York, 1986), pp. 34–37; and D. Geldart, Types of Gas Fluidization, Powder Technology, 7 (1973) 285–292, the entire contents of which are incorporated herein by reference, particles may be classified as “Group A” or “Group B”.

[0047] Group A is understood by those skilled in the art to represent aerated powders with fluidization in a bubble-free range; high bed expansion; slow and linear degassing rates; bubble characteristics that may include the advantage of splitting / re-agglomerating bubbles, with maximum bubble size and large wake; high levels of solids mixing and gas backmixing, assuming equal U-umf (U is the carrier gas velocity, and Umf is the minimum fluidization velocity, typically but not necessarily measured in meters per second (m / s), i.e., where excessively high gas velocities exist); axisymmetric bulk characteristics; and no sputtering except in very shallow beds. The listed characteristics tend to improve with decreasing average particle size, assuming equal cfp; or with increasing proportions of <45 micrometers (μm); or with increasing gas pressure, temperature, viscosity, and density. Generally, the particles may exhibit small average particle size and / or low particle density (<1.4 g / cm³). 3 It is easily fluidized, exhibiting smooth fluidization at low gas velocities and controlled bubbling with small bubbles at higher gas velocities.

[0048] Group B is understood by those skilled in the art to represent "sand-like" powders, which start to bubble at Umf; exhibit moderate bed expansion; rapid degassing; no limitation on bubble size; moderate levels of solid mixing and gas backmixing, assuming equal U-umf; both axisymmetric and asymmetric lumps; and spout only in shallow beds. These characteristics tend to improve with decreasing average particle size, but the particle size distribution and certain uncertainties in the gas, pressure, temperature, viscosity or density seem to have little effect on improving these characteristics. Generally, when the density (pp) is 1.4 < pp < 4 g / cm 3 , the particle size (cfp) of most particles is 40 μm < cfp < 500 μm, and preferably, when the density (pp) is 4 g / cm 3 , the particle size of most particles is 60 μm < cfp < 500 μm, and when the density (pp) is 1 g / cm 3 , the particle size of most particles is 250 μm < cfp < 100 μm.

[0049] In one or more embodiments, the oxygen carrier materials described herein can be prepared by a variety of synthesis 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. Generally, the various components in the oxygen carrier can be added in the form of solid powders of their oxide forms, then thoroughly mixed or homogenized, and subsequently calcined in air at high temperature. Alternatively, some of the components in the oxygen carrier can be incorporated by dissolving their precursors completely (wet or dry impregnation) or partially (slurry impregnation) in water, then combining them with the solid powders of the remaining components, and subsequently drying and performing high-temperature calcination in air. During the synthesis of the oxygen carrier, silica can be added to provide physical strength and stability.

[0050] In some embodiments, as described above, the oxygen carrier can be prepared by impregnation. The impregnation can utilize wet impregnation or dry impregnation (sometimes referred to as incipient wetness impregnation). The impregnation can utilize an aqueous solution including some of the components of the oxygen carrier. For example, in various embodiments, the aqueous solution can contain one or more precursors of the elements contained in the oxygen carrier material. In one or more embodiments, the aqueous solution can have a pH greater than 7. For example, the aqueous solution can have a pH 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 can occur to impregnate different materials.

[0051] The impregnated material can then be dried after impregnation. In some embodiments, the impregnated material can be dried in air. In one or more embodiments, the impregnated material can be dried at temperatures below 200°C, such as below 175°C, below 150°C, below 125°C, below 100°C, below 75°C, or even below 50°C. In some embodiments, impregnation can be performed more than once using an aqueous solution, and the impregnated material can be dried between each impregnation.

[0052] The dried, impregnated material can then be calcined to produce an oxygen carrier material. In one or more embodiments, calcination can be performed at temperatures above 600°C, such as above 700°C, above 800°C, above 900°C, above 1000°C, above 1100°C, or even above 1200°C. In one or more embodiments, the dried, impregnated material can be calcined in air. In embodiments utilizing multiple impregnation steps, the impregnated material can be calcined between each impregnation. In embodiments, the dried, impregnated material can be calcined in air for more than 1 hour. For example, the dried, impregnated material can be calcined in air for more than 2 hours, more than 4 hours, more than 10 hours, or even more than 20 hours.

[0053] In some embodiments, the oxygen carrier material can be used in processes including fluidized beds, moving beds, or circulating fluidized beds (CFB). In such embodiments, it may be desirable to have the oxygen carrier as engineered particles with "Geldart A" or "Geldart B" properties. Without being theoretically limited, in one or more embodiments, it is believed that a choice of methods for preparing engineered particles of the oxygen carrier material (such as manufacturing techniques like spray drying, high-shear granulation, and fluidized bed granulation), followed by drying and high-temperature calcination, can be used to obtain fluidizable particles.

[0054] This disclosure includes many aspects, including aspects 1 to 15 described below.

[0055] Aspect 1. A method for producing an olefin compound, the method comprising: passing a feed stream into a reactor, wherein the feed stream comprises one or more hydrocarbons; passing an oxygen carrier material into the reactor, wherein in the reactor: dehydrogenating the one or more hydrocarbons to form hydrogen and one or more olefin compounds; and reacting at least a portion of the hydrogen with oxygen from the oxygen carrier material to produce water; wherein at least 95% by weight of the oxygen carrier material comprises: 1 mole of iron; 1 to 20 mole of silicon dioxide; 1 to 3 mole of oxygen not contained in the silicon dioxide; and 0 to 1 mole of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium.

[0056] Aspect 2. The method according to any of the preceding aspects, wherein the oxygen carrier material comprises one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium.

[0057] Aspect 3. The method according to any of the preceding aspects, wherein the oxygen carrier material comprises one or more of strontium, calcium, or magnesium.

[0058] Aspect 4. The method according to any of the preceding aspects, wherein the oxygen carrier material comprises one or more of lanthanum, cerium, praseodymium, neodymium or samarium.

[0059] Aspect 5. The method according to any of the preceding aspects, wherein the oxygen carrier material comprises one or both of titanium or yttrium.

[0060] Aspect 6. The method according to any of the preceding aspects, wherein at least 99% by weight of the oxygen carrier material comprises: 1 mole of iron; 1 to 20 mole of silicon dioxide; 1 to 3 mole of oxygen not contained in the silicon dioxide; and 0 to 1 mole of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium or yttrium.

[0061] Aspect 7. The method according to any of the preceding aspects, wherein the oxygen carrier material comprises: 1 mole of iron; 1 to 20 mole of silicon dioxide; 1 to 3 mole of oxygen not contained in the silicon dioxide; and 0 to 1 mole of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium or yttrium.

[0062] Aspect 8. The method according to any of the preceding aspects, wherein: the one or more hydrocarbons include ethane, ethylbenzene, propane, butane or combinations thereof; and the one or more olefin compounds include ethylene, styrene, propylene, butene or combinations thereof.

[0063] Aspect 9. The method according to any of the preceding aspects, wherein the oxygen carrier material is circulated between the reactor and the regeneration unit, wherein the oxygen carrier material leaving the reactor is in an oxygen-deficient state, and the oxygen carrier material leaving the regeneration unit is in an oxygen-rich state.

[0064] Aspect 10. The method according to aspect 9, wherein fuel gas is burned in the regeneration unit to heat the oxygen carrier material.

[0065] Aspect 11. The method according to aspect 10, wherein the fuel gas comprises methane, ethane, propane, or combinations thereof.

[0066] Aspect 12. The method according to any of the preceding aspects, wherein the oxygen carrier material does not contain any alkali metal.

[0067] Aspect 13. The method according to any of the preceding aspects, wherein the reactor is operated as a fluidized bed reactor.

[0068] Aspect 14. The method according to any of the preceding aspects, wherein the reactor is operated at a temperature of 600°C to 850°C.

[0069] Aspect 15. The method according to any of the preceding aspects, wherein no dehydrogenation catalyst is used in the dehydrogenation reactor.

[0070] Example

[0071] Various embodiments of this disclosure will be further illustrated by the following examples. These examples are illustrative in nature and should not be construed as limiting the subject matter of this disclosure.

[0072] Example 1 - Sample Preparation

[0073] Comparative sample X was prepared by first obtaining commercially available quartz powder from Pyromatics and then sieving the quartz powder to 100 to 200 mesh before use.

[0074] Comparative sample A was prepared by first obtaining lanthanum nitrate hexahydrate (La(NO3)3•6H2O, Sigma-Aldrich, 99.999%), strontium nitrate (Sr(NO3)2, Sigma-Aldrich, 99.0%), ferric nitrate nonahydrate (Fe(NO3)3•9H2O, Sigma-Aldrich, 98%), citric acid (CA, Alfa Aesar, 99%), and ethylene glycol (EG, Fisher Scientific, 99%) (all commercially available and used as is). Comparative sample A was synthesized using the Pechini method: La(NO3)3•6H2O, Sr(NO3)2, and Fe(NO3)3•9H2O were dissolved in deionized water. Citric acid was then added at a molar ratio of CA:Fe = 5:1. The reaction mixture was stirred at 80°C for 2 hours to ensure that all citric acid was dissolved. Ethylene glycol was then added at a molar ratio of EG:Fe = 7.5:1. The gel precursor was then prepared by calcining the clarified solution at 130°C for 10 hours. The gel was further calcined in static air at 450°C for 3 hours and then at 750°C for 10 hours.

[0075] Comparative sample B was prepared by first obtaining iron oxide (Fe₂O₃, Noah Technologies Corporation, -325 mesh, 99.95%) and titanium oxide (TiO₂, Sigma-Aldrich, 21 nm nanoparticles, 99.5%) (both commercially available and used as is). Stoichiometric amounts of Fe₂O₃ and TiO₂ were weighed into a mortar. First, the dry powder was ground with a pestle for 5 minutes. Then, the powder was shaken in a separate container for 1 minute and returned to the mortar. The grinding and shaking steps were repeated twice (a total of 10 minutes of grinding and 2 minutes of shaking). Subsequently, after introducing 5 to 10 mL of deionized H₂O, the powder was ground and gelatinized for 5 minutes. The paste was then transferred to an alumina crucible and dried in air at 120°C for at least 2 hours. The dried mixture was calcined in air at 800°C for 24 hours.

[0076] Comparative sample C was prepared using only Fe2O3 in the same manner as comparative sample B, and was calcined at 950°C for 6 hours.

[0077] Comparative sample D was prepared by first obtaining SIRALOX 1.5 / 70 (Sasol, 1.5 wt% SiO2 / 98.5 wt% Al2O3 dry basis) (commercially available and used as is). Stoichiometric amounts of La(NO3)3•6H2O, Sr(NO3)2, and Fe(NO3)3•9H2O, along with citric acid, were added to deionized water at a molar ratio of Fe:CA = 1:2.2 to form a concentrated solution. The solution was slowly added to a wide-mouth flask containing the desired amount of SIRALOX 1.5 / 70 while gently stirring. After addition, the mixture was heated on a hot plate at 100°C until the contents were almost dry, then transferred to an alumina boat and gradually heated at 120°C for 5 hours, then at 450°C for 1 hour, and finally calcined at 750°C for 6 hours.

[0078] Comparative sample E was prepared by first obtaining SIRAL 5 (Sasol, 5 wt% SiO2 / 95 wt% Al2O3 dry basis) (commercially available and used as is). Stoichiometric amounts of La(NO3)3•6H2O, Sr(NO3)2, and Fe(NO3)3•9H2O were weighed and subsequently dissolved in 100 mL of deionized H2O in a 1 L beaker with vigorous stirring. Citric acid and ethylene glycol were then weighed and subsequently added to the solution in a molar ratio of (La+Sr+Fe):CA:EG = 1:1:1. Then, the desired amount of SIRAL 5 powder was added to the solution while stirring. The slurry was heated to 80 °C and stirred at a constant temperature at 80 °C until gelation occurred, which was identified by a residual liquid in a non-free-flowing state of <10 mL. The gel was transferred to an alumina crucible and dried in air at 120 °C for at least 5 hours. The dried gel was calcined at 450°C for 1 hour, and finally calcined at 750°C for 6 hours.

[0079] Comparative sample F was prepared by first obtaining SIRAL 40 (Sasol, 40 wt% SiO2 / 60 wt% Al2O3 dry basis) (commercially available and used as is). Comparative sample F was prepared in the same manner as comparative sample E, except that SIRAL 40 was used instead of SIRAL 5.

[0080] Comparative sample G was prepared by first obtaining PURALOX L3 (Sasol, 3 wt% La2O3 / 97 wt% Al2O3 dry basis) (commercially available and used as is). Comparative sample G was prepared in the same manner as comparative sample E, except that PURALOX L3 was used instead of SIRAL 5.

[0081] Comparative samples H, I, J, and K were prepared by first obtaining cerium dioxide (CeO2, Sigma-Aldrich, <50 nm particle size, 99.95%), zirconium dioxide (ZrO2, Sigma-Aldrich, 5 μm, 99%), titanium dioxide (TiO2, Sigma-Aldrich, 21 nm nanoparticle powder, 99.5%), and TiSol A colloidal titanium dioxide (NYACOL, 20 wt% TiO2) (all commercially available and used as is). Comparative samples H, I, J, and K were prepared in the same manner as comparative sample D, except that solid CeO2, solid ZrO2, solid TiO2, and TiSol A solution were used instead of SIRALOX 1.5 / 70, respectively.

[0082] Comparative sample L was prepared in the same manner as comparative sample K, except that the amounts of precursors (La(NO3)3•6H2O, Sr(NO3)2, Fe(NO3)3•9H2O, CA, and TiSol A) were adjusted to obtain different La 0.8 Sr 0.2 The weight ratio of FeO3 to TiO2.

[0083] Comparative sample M was prepared by first obtaining cobalt nitrate hexahydrate (Co(NO3)2•6H2O, Sigma-Aldrich, 98%) and ES757 silica (ES757 SiO2, INEOSS) (both commercially available and used as is). Stoichiometric amounts of Sr(NO3)2, Co(NO3)2•6H2O, and citric acid were added to deionized water at a molar ratio of Co:CA = 1:2.2 to form a concentrated solution. The solution was added dropwise to a wide-mouth flask containing the desired amount of ES757 SiO2 under gentle stirring. After addition, the mixture was heated on a hot plate at 100°C until it became almost dry. The mixture was then transferred to an alumina boat and gradually heated at 120°C for 5 hours, then at 450°C for 1 hour, and finally calcined at 750°C for 6 hours.

[0084] Comparative sample N was prepared by first adding stoichiometric amounts of La(NO3)3•6H2O, Sr(NO3)2, and Fe(NO3)3•9H2O, along with citric acid, to deionized water at a molar ratio of Fe:CA = 1:2.2 to form a concentrated solution. The solution was then slowly added to a wide-mouth flask containing the desired amount of ES757 SiO2 under gentle stirring. After addition, the mixture was heated on a hot plate at 100°C until it became almost dry. The mixture was then transferred to an alumina boat and gradually heated at 120°C for 5 hours, then at 450°C for 1 hour, and finally calcined at 750°C for 6 hours.

[0085] Comparative sample O was prepared in the same manner as comparative sample N, except that the mixture was calcined at 450°C for 1 hour and then calcined at 900°C for 6 hours.

[0086] By first obtaining LUDOX ® Comparative sample P was prepared using AS-30 colloidal silica (Sigma-Aldrich, 30 wt% SiO2) (commercially available and used as is). Dry Fe2O3 was weighed into a mortar. Subsequently, LUDOX was introduced into the powder based on the desired final SiO2 content. ®The AS-30 solution was then ground for 10 minutes. The mixture was then transferred to an alumina crucible and dried in air at 120°C for at least 2 hours. The dried mixture was then calcined in air at 750°C for 6 hours.

[0087] Sample 1 was prepared by first obtaining pyrolyzed SiO2 (S-5505 SiO2, 0.2 μm to 0.3 μm average particle size, Sigma-Aldrich) (commercially available and used as is). Sample 1 was prepared in the same manner as comparative sample D, except that S-5505 SiO2 was used instead of SIRALOX 1.5 / 70.

[0088] Samples 2 and 3 were prepared in the same manner as comparative sample N, wherein the amounts of precursors (La(NO3)3•6H2O, Sr(NO3)2, Fe(NO3)3•9H2O, CA, and ES757 SiO2) were adjusted to obtain different La 0.8 Sr 0.2 The weight ratio of FeO3 to SiO2.

[0089] Sample 4 was prepared in the same manner as Sample 3, except that the dried gel was calcined at 450°C for 1 hour and then calcined at 900°C for 6 hours.

[0090] Sample 5 was prepared by impregnation. Fe(NO3)3•9H2O was dissolved in deionized water while stirring to form a concentrated solution. The solution was added dropwise to a wide-mouth flask containing Ineos ES757 SiO2 under gentle stirring. After addition, the mixture was heated on a hot plate at 100°C until the contents were almost dry, then transferred to an alumina boat and gradually heated at 120°C for 5 hours, then at 450°C for 1 hour, and finally calcined at 750°C for 6 hours.

[0091] Sample 6 was prepared in the same manner as Sample 3, except that the amounts of the precursors (La(NO3)3•6H2O, Fe(NO3)3•9H2O, and CA) were adjusted to produce LaFeO3 instead of La. 0.8 Sr 0.2 FeO3.

[0092] Sample 7 was prepared in the same manner as Sample 3, wherein the amounts of precursors (La(NO3)3•6H2O, Fe(NO3)3•9H2O, and CA) were adjusted to produce La. 0.4 Fe 1.6 O3 instead of La 0.8 Sr 0.2 FeO3.

[0093] Sample 8 was prepared by first obtaining calcium nitrate tetrahydrate (Ca(NO3)3•4H2O, Sigma-Aldrich, 99%) (commercially available and used as is). Sample 8 was prepared in the same manner as Sample 3, except that the amounts of the precursors (Ca(NO3)3•4H2O, Fe(NO3)3•9H2O, and CA) were adjusted to produce CaFeO. x Instead of La 0.8 Sr 0.2 FeO3.

[0094] Comparative sample 9 was prepared by first obtaining magnesium nitrate hexahydrate (Mg(NO3)2•6H2O, Sigma-Aldrich, 99%) (commercially available and used as is). Sample 9 was prepared in the same manner as sample 3, wherein the amounts of precursors (Mg(NO3)3•6H2O, Fe(NO3)3•9H2O, and CA) were adjusted to produce MgFeO. x Instead of La 0.8 Sr 0.2 FeO3.

[0095] Sample 10 was prepared by first weighing stoichiometric amounts of La(NO3)3•6H2O, Sr(NO3)2, and Fe(NO3)3•9H2O. While stirring, the mixture was dissolved in 30 mL of deionized H2O in a 50 mL vial. Subsequently, citric acid and ethylene glycol were weighed and added to the metal nitrate solution in a molar ratio of (La+Sr+Fe):CA:EG = 1:1:1. The desired amount of LUDOX was then diluted separately in a 1 L beaker with 70 mL of deionized H2O. ® AS-30 solution. The metal nitrate solution was added dropwise to the diluted LUDOX solution while vigorous stirring. ® The solution was prepared in AS-30. The mixture was heated to 80°C and stirred continuously at 80°C until gelation occurred, which was identified by the presence of <10 mL of non-free-flowing residual liquid. The gel was transferred to an alumina crucible and dried in air at 120°C for at least 5 hours. The dried gel was calcined at 450°C for 1 hour and finally at 750°C for 6 hours.

[0096] By first obtaining LUDOX ® Sample 11 was prepared using AS-40 colloidal silica (Sigma-Aldrich, 40 wt% SiO2) (commercially available and used as is). Sample 11 was prepared in the same manner as Sample 10, except that LUDOX was used. ® AS-40 replaces LUDOX ® AS-30.

[0097] Samples 12 and 13 were prepared in the same manner and formulation as samples 10 and 11, except that the dried gel was calcined at 450°C for 1 hour and finally calcined at 900°C for 6 hours.

[0098] Sample 14 was prepared by first dissolving Fe(NO3)3•9H2O in deionized water while stirring to form a concentrated solution. Subsequently, the desired amount of LUDOX was added... ® AS-30 solution is added to the iron-containing solution. The mixture is heated on a hot plate at 80°C until the liquid is almost non-flowing. The viscous liquid is transferred to an alumina boat and gradually heated at 120°C for 5 hours, then at 450°C for 1 hour, and finally calcined at 750°C for 6 hours.

[0099] Sample 15 was prepared by first dissolving Fe(NO3)3•9H2O in deionized water while stirring to form a concentrated solution. Citric acid and ethylene glycol were then weighed and subsequently added to the metal nitrate solution at a molar ratio of Fe:CA:EG = 1:1:1.5. The desired amount of LUDOX was then added. ® AS-30 solution was added dropwise to the iron-containing solution. The mixture was heated to 80°C and stirred continuously at 80°C until gelation occurred, which was identified by the presence of <10 mL of non-free-flowing residual liquid. The gel was transferred to an alumina crucible and dried in air at 120°C for at least 5 hours. The dried gel was calcined at 450°C for 1 hour and finally at 750°C for 6 hours.

[0100] Sample 16 was prepared in the same manner as comparative sample P, except that the Fe2O3 and LUDOX were varied. ® The ratio of AS-30.

[0101] Sample 17 was prepared by first obtaining iron-titanium oxide (FeTiO3, Thermoscientific, 99.8%) (commercially available and used as is). Sample 17 was prepared in the same manner as comparative sample P, wherein FeTiO3 and LUDOX were used. ® Different ratios of AS-30 were used to replace Fe2O3 with FeTiO3.

[0102] Example 2 - Selective Hydrogen Combustion Performance

[0103] The selective hydrogen combustion performance of the sample was evaluated in a U-shaped fixed-bed reactor made of quartz. First, 125 mg of sample was prepared with a size of 100-200 mesh and diluted with 400 mg of quartz flakes (100-200 mesh) before being loaded into the reactor. The sample was heated to 750 °C under an air stream, purged with helium, and then subjected to three cycles at 750 °C at a total gas flow rate of 12 standard cubic centimeters (sccm). In each cycle, the sample was first exposed to 90% C₂H₆ / 10% N₂ for 1 minute, purged with helium, and finally regenerated in air for 15 minutes. After 23 seconds of ethane exposure, the composition of the outlet gas was analyzed by gas chromatography. The data presented in Table 1 below are the average values ​​from the three cycles.

[0104] The following formula is used to calculate ethane conversion and carbon-based selectivity, where [X] corresponds to the mole fraction and IS corresponds to the internal standard.

[0105]

[0107]

[0108] As shown in Table 1, samples containing silica (SiO2) exhibited improved CO2 content compared to samples without silica. x Selectivity and H2 / C2H4 ratio. For example, comparative sample A, which contains no binder, has 26.0% CO2. x Selectivity and an H2 / C2H4 ratio of 5.96. Contains (SiO2). 3.87 Sample 1 has 4.0% CO. x Selectivity and an H2 / C2H4 ratio of 0.50.

[0109] Furthermore, samples containing both iron and silicon dioxide performed better than samples containing silicon dioxide but lacking iron, and samples containing neither iron nor silicon dioxide. For example, samples lacking iron and (SiO2)... 3.24 The comparative sample M had 64.6% C2H4 selectivity and 31.0% CO selectivity. x Selectivity and an H2 / C2H4 ratio of 3.17. Conversely, iron and (SiO2) are present. 3.87 Sample 1 exhibited 89.0% C2H4 selectivity and 4.0% CO selectivity. xSelectivity and an H2 / C2H4 ratio of 0.50 show improvement in all three measurements. Furthermore, the comparative sample X, which contains neither iron nor silica, has a higher H2 / C2H4 ratio than samples containing both iron and SiO2 (such as sample 1), indicating that the presence of both iron and silica improves selective hydrogen combustion.

[0110] Table 1 also shows that other binder materials are not as effective as silica. Comparative samples D through L all have binder materials different from silica and exhibit worse performance data than samples containing silica as a binder. For example, comparative sample D, containing SiO2-doped Al2O3 as a binder, has 0.7% C2H4 selectivity and 28.0% CO2 selectivity. x Selectivity and H2 / C2H4 ratio of 1077. Sample 1, containing SiO2 as a binder, has 89.0% C2H4 selectivity and 4.0% CO2 selectivity. x Selectivity and an H2 / C2H4 ratio of 0.50.

[0111] Finally, samples containing less than 1 mole of silica performed worse than those containing more than 1 mole of silica. For example, both N and O samples contained 0.97 moles of silica. As shown in Sample 1, even when the silica content increased to 3.87 moles, the overall performance of the measurement data was better. Additionally, samples containing FeO... 1.5 and (SiO2) 0.33 The comparative sample P of the base composition has a higher content than that containing the same base composition FeO. 1.5 But it contains (SiO2) 1.33 Sample 5 had even worse performance.

[0112] Therefore, Table 1 shows that, in addition to iron, the presence of SiO2 improves the selectivity of hydrogen combustion relative to hydrocarbons, resulting in lower CO levels. x This formation significantly improves ethylene selectivity and CO2 selectivity. x Selectivity and / or H2 / C2H4 ratio.

[0113] It will be apparent to those skilled in the art that various modifications and variations can be made to the technology disclosed herein without departing from the spirit and scope of this invention. Because modifications, combinations, sub-combinations, and variations of the disclosed embodiments can be made by those skilled in the art that incorporate the spirit and essence of the technology disclosed herein, this technology should be construed as including all things within the scope of the appended claims and their equivalents. Furthermore, although some aspects of this disclosure may be identified herein as preferred or particularly advantageous, this disclosure is not limited to these aspects upon consideration.

[0114] It should be noted that the various details described in this disclosure should not be construed as implying that such details relate to elements that are fundamental components of the various embodiments described in this disclosure, even where specific elements are shown in each of the accompanying drawings. Unless so expressly stated, none of the features disclosed and described herein should be interpreted as "essential." The embodiments considered in this art include those that include some or all of the features of the appended claims.

[0115] For the purposes of describing and defining this disclosure, it should be noted that the term "about" is used in this disclosure to indicate an inherent uncertainty attributable to any quantitative comparison, value, measurement, or other representation. The term "about" is also used in this disclosure to indicate the degree to which a quantitative representation may vary from a specified reference without causing a change in the essential function of the subject matter of interest.

[0116] In relevant contexts, where a composition is described as "comprising" one or more elements, embodiments of compositions "composed of" or "substantially composed of" those one or more elements are considered herein.

[0117] It should be understood that, in some embodiments, the composition range of a chemical component in a stream or reactor should be understood as a mixture containing isomers of that component. For example, specifying the composition range of butene may include a mixture of various isomers of butene. It should be understood that the embodiments provide composition ranges for various streams, and the total amount of isomers of a particular chemical composition may constitute a range.

[0118] It should be noted that one or more of the following claims and detailed descriptions utilize the terms "where" or "wherein" as transitional phrases. For the purpose of defining this technology, it should be noted that this term is introduced in the claims as an open transitional phrase used to introduce a description of a series of characteristics of the structure, and should be interpreted in a manner similar to the more commonly used open prepositional term "comprising".

[0119] It should be understood that any two quantitative values ​​assigned to a characteristic can constitute a range for that characteristic, and all combinations of ranges formed by all stated quantitative values ​​of a given characteristic are considered in this disclosure. Where multiple ranges of quantitative values ​​are provided, these ranges can be combined to form a wider range, as is considered in the embodiments described herein.

[0120] As understood in the context of the terminology used herein, the term "transfer" can include the direct transfer of substance between two parts of the disclosed system, and in some cases, it means the indirect transfer of substance between two parts of the disclosed system. For example, indirect transfer can include steps in which the specified substance is transferred through intermediate operating units, valves, sensors, etc. Claims (as amended under Article 19 of the Treaty) 1. A method for producing an olefin compound, the method comprising: A feed stream is passed into the reactor, wherein the feed stream contains one or more hydrocarbons; The oxygen carrier material is transferred into the reactor, wherein in the reactor: The one or more hydrocarbons are dehydrogenated to form hydrogen gas and one or more olefin compounds; and At least a portion of the hydrogen gas is reacted with oxygen from the oxygen carrier material to produce water; At least 95% by weight of the oxygen carrier material comprises the following: 1 mole of iron; 1 to 20 moles of silicon dioxide; 1 to 3 moles of oxygen not contained in the silica; and From 0.001 moles to 1 mole of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium or yttrium. 2. The method according to any of the preceding claims, wherein the oxygen carrier material comprises one or more of strontium, calcium, or magnesium. 3. The method according to any of the preceding claims, wherein the oxygen carrier material comprises one or more of lanthanum, cerium, praseodymium, neodymium, or samarium. 4. The method according to any of the preceding claims, wherein the oxygen carrier material comprises one or both of titanium or yttrium. 5. The method according to any preceding claim, wherein at least 99% by weight of the oxygen carrier material comprises the following: 1 mole of iron; 1 to 20 moles of silicon dioxide; 1 to 3 moles of oxygen not contained in the silica; and From 0.001 moles to 1 mole of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium or yttrium. 6. The method according to any preceding claim, wherein the oxygen carrier material comprises the following: 1 mole of iron; 1 to 20 moles of silicon dioxide; 1 to 3 moles of oxygen not contained in the silica; and From 0.001 moles to 1 mole of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium or yttrium. 7. The method according to any of the preceding claims, wherein: The one or more hydrocarbons include ethane, ethylbenzene, propane, butane, or combinations thereof; and The one or more olefin compounds include ethylene, styrene, propylene, butene, or combinations thereof. 8. The method according to any of the preceding claims, wherein the oxygen carrier material is circulated between the reactor and the regeneration unit, wherein the oxygen carrier material leaving the reactor is in an oxygen-deficient state, and the oxygen carrier material leaving the regeneration unit is in an oxygen-rich state. 9. The method of claim 8, wherein fuel gas is burned in the regeneration unit to heat the oxygen carrier material. 10. The method of claim 9, wherein the fuel gas comprises methane, ethane, propane, or a combination thereof. 11. The method according to any of the preceding claims, wherein the oxygen carrier material does not contain any alkali metal. 12. The method according to any of the preceding claims, wherein the reactor is operated as a fluidized bed reactor. 13. The method according to any of the preceding claims, wherein the reactor is operated at a temperature of 600°C to 850°C. 14. The method according to any of the preceding claims, wherein no dehydrogenation catalyst is used in the dehydrogenation reactor.

Claims

1. A method for producing an olefin compound, the method comprising: A feed stream is passed into the reactor, wherein the feed stream contains one or more hydrocarbons; The oxygen carrier material is transferred into the reactor, wherein in the reactor: The one or more hydrocarbons are dehydrogenated to form hydrogen gas and one or more olefin compounds; and At least a portion of the hydrogen gas is reacted with oxygen from the oxygen carrier material to produce water; At least 95% by weight of the oxygen carrier material comprises the following: 1 mole of iron; 1 to 20 moles of silicon dioxide; 1 to 3 moles of oxygen not contained in the silica; and A combination of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium or yttrium, from 0 to 1 mole.

2. The method according to any preceding claim, wherein the oxygen carrier material comprises one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium, or yttrium.

3. The method according to any of the preceding claims, wherein the oxygen carrier material comprises one or more of strontium, calcium, or magnesium.

4. The method according to any of the preceding claims, wherein the oxygen carrier material comprises one or more of lanthanum, cerium, praseodymium, neodymium, or samarium.

5. The method according to any of the preceding claims, wherein the oxygen carrier material comprises one or both of titanium or yttrium.

6. The method according to any preceding claim, wherein at least 99% by weight of the oxygen carrier material comprises the following: 1 mole of iron; 1 to 20 moles of silicon dioxide; 1 to 3 moles of oxygen not contained in the silica; and A combination of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium or yttrium, from 0 to 1 mole.

7. The method according to any preceding claim, wherein the oxygen carrier material comprises the following: 1 mole of iron; 1 to 20 moles of silicon dioxide; 1 to 3 moles of oxygen not contained in the silica; and A combination of one or more of strontium, calcium, magnesium, titanium, lanthanum, cerium, praseodymium, neodymium, samarium or yttrium, from 0 to 1 mole.

8. The method according to any of the preceding claims, wherein: The one or more hydrocarbons include ethane, ethylbenzene, propane, butane, or combinations thereof; and The one or more olefin compounds include ethylene, styrene, propylene, butene, or combinations thereof.

9. The method according to any of the preceding claims, wherein the oxygen carrier material is circulated between the reactor and the regeneration unit, wherein the oxygen carrier material leaving the reactor is in an oxygen-deficient state, and the oxygen carrier material leaving the regeneration unit is in an oxygen-rich state.

10. The method of claim 9, wherein fuel gas is burned in the regeneration unit to heat the oxygen carrier material.

11. The method of claim 10, wherein the fuel gas comprises methane, ethane, propane, or combinations thereof.

12. The method according to any of the preceding claims, wherein the oxygen carrier material does not contain any alkali metal.

13. The method according to any of the preceding claims, wherein the reactor is operated as a fluidized bed reactor.

14. The method according to any of the preceding claims, wherein the reactor is operated at a temperature of 600°C to 850°C.

15. The method according to any of the preceding claims, wherein no dehydrogenation catalyst is used in the dehydrogenation reactor.

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