Methods for dehydrogenating hydrocarbons utilizing moving bed reactors and water separation

Abstract

According to one or more embodiments, a method for dehydrogenating hydrocarbons may comprise dehydrogenating hydrocarbons in a moving bed reactor comprising two or more sections. After each section, water may be removed to reduce the concentration of water in the subsequent sections.

Description

86326-WO-PCT / DOW 86326 WO1METHODS FOR DEHYDROGENATING HYDROCARBONS UTILIZING MOVING BED REACTORS AND WATER SEPARATIONCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U. S. Provisional Application Serial No.63 / 779,683 filed March 28, 2025, the contents of which are incorporated by reference in their entirety herein.TECHNICAL FIELD

[0002] Embodiments described herein generally relate to chemical processing and, more specifically, to processes and systems utilized for dehydrogenation of chemical species.BACKGROUND

[0003] Olefinic compounds may be utilized as base materials to produce many types of goods and materials. For example, ethylene may be utilized to manufacture polyethylene, ethylene chloride, or ethylene oxides. Such products may be utilized in product packaging, construction, textiles, etc. Thus, there is an industry demand for olefinic compounds, such as ethylene, propylene, butene, and styrene.SUMMARY

[0004] One method for producing olefinic compounds is by dehydrogenating alkanes and / or alkyl aromatics. In some embodiments, the dehydrogenation reaction may be promoted by removing hydrogen formed during dehydrogenation by reacting the hydrogen with oxygen to form water, which pushes the equilibrium towards the light olefin products. In such embodiments, an oxygen-carrier material may be utilized to provide the oxygen that reacts with the hydrogen. The oxygen-carrier material may be included in a particulate solid. However, the production of water in the dehydrogenation zone may result in decreased olefin product selectivity (e.g., due to steam reforming of hydrocarbons to CO and CO2). Thus, it may be desirable to reduce the concentration of water in the dehydrogenation zone.86326-WO-PCT / DOW 86326 WO2

[0005] In some embodiments, the dehydrogenation reaction may be promoted by through the use of a dehydrogenation catalyst. The dehydrogenation catalyst may be present as part of the particulate solid. For example, the particulate solid may comprise separate particles of dehydrogenation catalyst and oxygen-carrier material, individual particles of mixed dehydrogenation catalyst and oxygen-carrier material, and / or dual purpose dehydrogenation catalyst / oxygen-carrier materials. In any configuration, the use of dehydrogenation catalyst may serve to reduce reaction temperatures, improve reaction kinetics, improve overall conversion of feedstocks, and / or improve product selectivity. However, the dehydrogenation catalysts are often inhibited by the presence of steam or water in the reaction zone. Thus, it may be particularly desirable to reduce the concentration of water in the dehydrogenation zone when a dehydrogenation catalyst is used.

[0006] Embodiments of the present disclosure meet this need by positioning the dehydrogenation zone in a moving bed reactor and removing water from the dehydrogenation zone one or more times. These features may result in improved reaction equilibrium, improved overall conversion, and / or improved yield and / or selectivity of desired products (e.g., ethylene).

[0007] The placement of the dehydrogenation zone in a moving bed enables ready separation of gas streams (including water in the form of steam) from solids. The use of a moving bed allows this to be done more conveniently. The use of a moving bed may allow this separation to take place without cooling and subsequent reheating of the gas stream and / or particulate solids, thereby improving efficiency. The use of a moving bed may also allow this separation to take place without the need for gas-solid separation devices like cyclones, thereby reducing capital costs. Finally, the use of a moving bed dehydrogenation zone may result in reduced attrition of particulate solids, thereby further reducing operational costs.

[0008] As described hereinabove, the removing water from the dehydrogenation zone one or more times (sometimes referred to herein as “staged water removal”) may help overcome equilibrium constraints arising from the buildup of water in the reactor. For example, water buildup may result in re-oxidation of reduced metal oxide and production of hydrogen, as shown in the equilibrium equation below. By removing water from the process, this equilibrium constraint can be addressed.86326-WO-PCT / DOW 86326 WO3Fe3O4+ H2↔ 3FeO + H2O

[0009] According to one or more embodiments described herein, A method for dehydrogenating hydrocarbons may comprise: passing a feed stream and a particulate solid into a moving bed reactor, the feed stream comprising one or more hydrocarbons, the particulate solid comprising an oxygen-carrier material, and wherein: the moving bed reactor comprises a dehydrogenation zone that comprises a first section and a second section, the first section positioned upstream of the second section, wherein the particulate solids move from the first section to the second section through the dehydrogenation zone; in the first section, a portion of the one or more hydrocarbons of the feed stream are dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen is reacted with oxygen from the oxygen-carrier material to form water; passing a water-rich fluid stream from the first section into a water removal device, the water-rich fluid stream comprising water, unreacted hydrocarbons, and dehydrogenated products, wherein in the water removal device a portion or all of the water is removed from the water-rich fluid stream to form a water-reduced fluid stream; passing the water-reduced fluid stream into the second section; and passing the portion of the water, unreacted hydrocarbons, and dehydrogenated products that do not pass through the water removal device to the second section, wherein in the second section a portion of the hydrocarbons of the feed stream are dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen is reacted with oxygen from the oxygen-carrier material to form water.

[0010] It is to be understood that both the preceding 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. Additional features and advantages of the embodiments will be set forth in the detailed description and, in part, will be readily apparent to persons of ordinary skill in the art from that description, which includes the accompanying drawings and claims, or recognized by practicing the described embodiments. The drawings are included to provide a further understanding of the embodiments and, together with the detailed description, serves to explain the principles and operations of the86326-WO-PCT / DOW 86326 WO4claimed subject matter. However, the embodiments depicted in the drawings are illustrative and exemplary in nature, and not intended to limit the claimed subject matter.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Reference will now be made in greater detail to various embodiments, some of which are illustrated in the accompanying drawings, wherein:

[0012] FIG. 1 schematically depicts a reactor system, according to one or more embodiments of the present disclosure;

[0013] FIG. 2 schematically depicts another reactor system, according to one or more embodiments of the present disclosure; and

[0014] FIG. 3 schematically depicts yet another reactor system, according to one or more embodiments of the present disclosure.

[0015] When describing the simplified schematic illustrations of FIG. 1 to FIG. 3, the numerous pumps, valves, temperature sensors, electronic controllers, and the like, which may be used and are well known to a person of ordinary skill in the art, are not included. Further, accompanying components that are often included in such reactor systems, such as air supplies, heat exchangers, surge tanks, and the like are also not included. However, it should be understood that these components are within the scope of the present disclosure.

[0016] Reference will now be made in greater detail to various embodiments, some embodiments of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or similar parts.DETAILED DESCRIPTION

[0017] Embodiments of the methods presently disclosed will now be described herein in detail in the context of the reaction systems of FIG. 1 to FIG. 3 operating to dehydrogenate hydrocarbons. However, it should be understood that the principles disclosed and taught herein may be applicable to other systems which utilize different system components oriented in different ways. It should be further understood that not all portions of the reaction systems of FIG. 1 to FIG. 3 should be construed as essential to the claimed subject matter. Moreover, while86326-WO-PCT / DOW 86326 WO5the recited method steps in the appended claims are described herein in the context of the reaction systems of FIG. 1 to FIG. 3, such recited method steps should be understood as adaptable to other systems, as would be understood by those skilled in the art.

[0018] As described in more detail below, a reaction system may comprise a dehydrogenation zone positioned within a moving bed of a moving bed reactor. One or more hydrocarbons and fresh particulate solid may be fed to the dehydrogenation zone, wherein the one or more hydrocarbons may be dehydrogenated to form dehydrogenated products. Additionally, the dehydrogenation zone may be divided into two or more sections (e.g., a first section and a second section) and water may be removed from the system between at least the first section and the second section. Several broad concepts will be discussed first and then each of the embodiments depicted in the figures will be described subsequently.

[0019] Moving bed reactors, as described herein, are generally known to those skilled in the art for use in a wide variety of chemical conversion processes. As used herein, a “moving bed reactor” may refer to a reactor having a moving bed wherein solid particles move relatively slowly downwards in a controlled manner due primarily to gravity. In a moving bed, the particles generally maintain contact with one another and are not suspended in fluid, i.e., the moving bed reactor is not a fluidized bed reactor. In general, the moving bed reactor can be thought of as a packed bed reactor that continuously moves generally downward through a reactor or reactor section. Advantages of using a moving bed reactor include reduced particle attrition, simplified process equipment (e.g., through the removal of complex solid / vapor separators such as cyclones), more precise control over oxidation states of the oxygen-carrier material, relative to fluidized reactor based systems. Additionally, in fluidized bed systems, the individual particles of the particulate solid may each be reduced to a random degree which may decrease selectivity. However, in a moving bed reactor, the individual particles may not be randomly mixed and thus may be reduced more uniformly, leading to improved reaction kinetics and enhancements in overall reaction selectivity of the dehydrogenation reaction.

[0020] As used herein, a “reaction zone” (e.g. A dehydrogenation zone) refers to a portion of a reactor where the named reaction is occurring. In embodiments, the named reaction may be the predominant reaction occurring in the reaction zone. As used herein, “dehydrogenation zone” refers to a reaction zone wherein the predominant reaction is dehydrogenation (e.g., the removal86326-WO-PCT / DOW 86326 WO6of hydrogen atoms from hydrocarbons). Additionally, in the dehydrogenation zone, molecular hydrogen produced in the dehydrogenation may be combusted to form water.

[0021] The reaction zone may be subdivided into one or more sections (e.g., a first section, a second, section, a third section, etc.). Each section may include a void space above the section where reactants may be added. In some embodiments, solids may flow between the sections via a standpipe. Each section may begin with an expanded portion that narrows as the solids flow down through the section. In the upper portion of each section (e.g., in the expanded portion), a water rich stream may be removed. A water lean stream may be reintroduced lower in the standpipe section of the moving bed.

[0022] As used herein, “water” refers to the compound H2O in whatever state it may be present. For example, “water” includes liquid water and steam.

[0023] Embodiments described herein may utilize a particulate solid. As used herein, the term “particulate solid” may refer to one or more solid particles. The particles may have a size and density such that they do not fluidize under the conditions in the moving bed reactor. The particulate solid may be prepared such that it meets the Geldart D classification. Group D particles tend to have particle sizes larger than 1000 pm and are characterized as spoutable. Very dense particles can also be characterized as Group D, even with particle sizes smaller than 1000 pm (e.g., metal particles). Unlike Group A or B particles that form fast clouded bubbles (i.e., bubble rise velocity is higher than interstitial gas velocity, and gas circulates between bubble and cloud), Group D particles tend to form slow cloudless bubbles (i.e., interstitial gas velocity is higher than bubble rise velocity, and emulsion phase gas flows through the bubble phase from bottom to top with negligible circulation). Previously, it was believed that Group D particles are unsuitable for use in dehydrogenation reactions as they require such high velocities for fluidization that processing gasses (e.g., ethylene dehydrogenation) would be impractical as gas velocity would be too high for sufficient conversion. However, it has recently been discovered that the use of Group D particles in a moving bed can result in efficient conversion.

[0024] The particulate solid may have an average particle size of from 0.3 mm to 5 mm, such as from 0.3 mm to 0.5 mm, from 0.5 mm to 0.75 mm, from 0.75 mm to 1.0 mm, from 1.0 mm to 2.0 mm, from 2.0 mm to 3.0 mm, from 3.0 mm to 4.0 mm, from 4.0 mm to 5.0 mm, or any combination of two or more of these ranges.86326-WO-PCT / DOW 86326 WO7

[0025] The particulate solid may have a density of from 1 g / cc to 5 g / cc, such as from 1 g / cc to 2 g / cc, from 2 g / cc to 3 g / cc, from 3 g / cc to 4 g / cc, from 4 g / cc to 5 g / cc, or any combination of two or more of these ranges.

[0026] In one or more embodiments, the particulate solid may comprise an “oxygen-carrier material” or both an oxygen-carrier material and a “dehydrogenation catalyst”, or both. In some embodiments, at least 5 wt. %, at least 10 wt. %, at least 25 wt. %, at least 50 wt. %, at least 75 wt. %, at least 85 wt. %, at least 90 wt. %, at least 92 wt. %, at least 94 wt. %, at least 96 wt. %, at least 98 wt. %, or at least 99 wt. % of the particulate solid may be the oxygen-carrier material. In some embodiments, the particulate solid may consist of, or consist essentially of, the oxygencarrier material. As used herein, “consists essentially of’ refers to materials with less than 1 wt. % of the non-recited materials (i.e., consisting essentially of A means A is at least 99 wt.% of the composition). In some embodiments, the particulate solid may not comprise a dehydrogenation catalyst material. In some embodiments, particulate solid may comprise the oxygen-carrier material and the dehydrogenation catalyst material as separate particles. In some embodiments, the oxygen-carrier material and the dehydrogenation catalyst may be contained in the same particles of the particulate solid. In some embodiments, the particulate solid may comprise a “dual-purpose material” that may act as both a dehydrogenation catalyst as well as an oxygen-carrier material. Such a dual-purpose material may be utilized either in replacement or in combination with the oxygen-carrier material or the dehydrogenation catalyst. In some embodiments, the particulate solid may encompass all solids in the system aside from coke.

[0027] In embodiments where the particulate solid comprises a dehydrogenation catalyst, the dehydrogenation of the one or more hydrocarbons may be at least partially by catalytic dehydrogenation. Catalytic dehydrogenation is the dehydrogenation of a hydrocarbon that is promoted by the use of a dehydrogenation catalyst. In embodiments, where the particulate solid does not comprise a dehydrogenation catalyst, the dehydrogenation of the one or more hydrocarbons may be by non-catalytic thermal dehydrogenation. Non-catalytic thermal dehydrogenation refers to the dehydrogenation of a hydrocarbon that occurs without the use of a dehydrogenation catalyst and instead may occur because of high temperature, pressure or combinations thereof.86326-WO-PCT / DOW 86326 WO8

[0028] As described herein, in one or more embodiments, the dehydrogenation catalyst and the oxygen-carrier material may be separate particles of the particulate solid. One contemplated advantage of such a system is that by adding, removing, or substituting one or both of the dehydrogenation catalyst and oxygen-carrier material, the functionality of the system can be altered, even when the system is on-line. For example, the reaction heat load could be adjusted by adding or removing one or both of the dehydrogenation catalyst and the oxygen-carrier material. This may be advantageous, in some embodiments, as compared with a dual purpose material, since the dual purpose particle's heat balance must be determined prior to reaction and cannot be easily adjusted by varying the amount of dehydrogenation catalyst versus oxygencarrier material. Control of the ratio of dehydrogenation catalyst versus oxy gen-carrier material may further be advantageous since reaction selectivity may be better tuned. For example, the amount of hydrogen in the system may be used to control the degree of combustion, or component balances may be used to optimize downstream separation processes.

[0029] The oxygen-carrier material may refer to one or more materials which may comprise oxygen atoms and which may increase or decrease the number of oxygen atoms bound thereto based on reaction conditions. For example, the oxygen-carrier material may include one or more metal oxides. According to one or more embodiments, the one or more metal oxides may be a redox-active metal oxide or a mixture of redox-active metal oxides. The redox-active metal oxide may include binary, ternary, or other mixed metal oxides capable of undergoing reduction in the presence of a reducing agent (for example, hydrogen) and oxidation in the presence of oxidizing agent (for example, oxygen or air). In some embodiments, the redox-active metal oxide may be a metal M0x, where M may be one or more metals of IUPAC group 6, 7, 8, 9, 10, 11, or 12 and “x” is the number of associated oxygen atoms in the structure. For example the redox-active metal oxide may be M112O3, Fe2Os, CO3O4, CuO, (LaSrjCoCh, (LaSr)MnCh, MgeMnOs, MgMnCh, MnCh, FesO4, MmCh, CU2O, NiO, N12O3, CrO, CnCh, CrCh, ZnO, or any combination of other IUPAC group 6-12 metal oxide. In some embodiments, the redox-active metal oxide may be cerium oxide. For example, the redox-active metal oxide may be Ce-Ch, Ce2C>3, or any other mixed metal oxide containing cerium. In further embodiments, the oxygen carrier material may include lanthanum oxide, LaiOs, in combination with other reducible metal oxides. In some embodiments, the redox-active metal oxide may be chosen from MmCh, Fe2C>3, CO3O4, CuO,86326-WO-PCT / DOW 86326 WO9(LaSr)CoO3,(LaSr)MnO3, MgeMnOs, MgMnCh, MnCh, FesCh, M113O4, and C112O. In some embodiments, the oxygen-carrier material may be a solid, such as solid particles. In specific embodiments, the oxy gen-carrier material may be a crushed solid or powder. In other embodiments, the oxygen-carrier material may be formulate using a redox-active metal oxide and a binder and / or support material to produce the particulate solid with the required physical properties, for example, particle size distribution, density, and attrition resistance. The binder and / or support material may include alumina, silica, titania, magnesia, zirconia, or combinations thereof.

[0030] In one or more embodiments, the particulate solid may include a hydrogen-selective oxygen-carrier material that may include a promoter or a combination of various promoters. The addition of a promoter(s) may lead to the formation of a core-shell morphology. The promoter(s) may include alkali or alkaline-earth metal oxides from IUPAC group 1 and 2 and / or compounds comprising alkali-transition metal oxides or alkaline-earth transition metal oxides. In some embodiments, alkali elements may include one or more of sodium, lithium, potassium, and cesium. In some embodiments, alkaline-earth elements may include one or more of calcium, magnesium, strontium, and barium. In some embodiments, transition metals may include one or more of tungsten and molybdenum. For example, the one or more alkali or alkaline-earth transition metal oxides may be NazWC, K2MOO4, Na2MoC>4, K2WO4, IJ2WO4, CsWCh, IJ2MOO4, CaWC>4, CaMoC>4, MgW04, MgMoC>4, SrWC>4, SrMoC>4, BaWC>4 and BaMoCh. In some embodiments, the promoter may include one or more of alkali or alkaline-earth metal salts selected from Group 1 and 2 metal cations and a counterion. In some embodiments, alkali elements may include one or more of sodium, lithium, potassium, and cesium. In some embodiments, alkaline-earth elements may include one or more of calcium, magnesium, strontium, and barium. In some embodiments, the counterion may include carbonates, sulphates, sulphites, sulfides, silicates, phosphates, phosphites and borates. For example, the alkali or alkaline-earth metal salts may be Na2CC>3, Na2SC>4, NasPCh, I 2CO3, IJ2SO4, IJ3PO4, K2CO3, K2SO4, K3PO4, CS2CO3, CS2SO4, CS3PO4, CaCO3, CaSO4, Ca3(PO4)2, SrCO3, SrSC, Sr3(PO4)2, MgCO3, MgSO4, Mg3(PO4)2, BaCO3, BaSCh, Ba3(PO4)2, Na2HPO4, KHSO4, Na2SO3, K2B4O7, NasBCh, or combinations thereof.86326-WO-PCT / DOW 86326 WO10

[0031] Some examples of suitable oxygen-carrier materials are disclosed in U. S. Pat. App. No.62 / 725,504, entitled “METHODS OF PRODUCING HYDROGEN-SELECTIVE OXYGEN CARRIER MATERIALS,” filed on, Aug. 31, 2018; U. S. Pat. App. No. 62 / 725,508, entitled “HYDROGEN-SELECTIVE OXYGEN CARRIER MATERIALS AND METHODS OF USE,” filed on, Aug. 31, 2018; U. S. Pat. No. 5,430,209; U. S. Pat. No. 7,122,495; and WO 2018 / 232133, each of which are incorporated by reference in their entireties.

[0032] The oxygen-carrier material may be reducible by releasing oxygen or may be oxidizable. The oxygen-carrier material may comprise releasable oxygen. As described herein, “releasable oxygen” may refer to the oxygen that can be released through redox by the oxygen-carrier material, such as through redox reactions with molecular hydrogen. Other oxygen may be present in the oxygen-carrier material that is not releasable through redox. It should be understood that in some embodiments, the oxygen may be released from a surface of the oxygen-carrier material simultaneously with the combustion of hydrogen at the surface of the oxygen-carrier material.

[0033] As described herein, in one or more embodiments, the particulate solid may comprise a dehydrogenation catalyst. In one or more embodiments, the dehydrogenation catalyst may include gallium, chromium, and / or platinum. As described herein, a gallium and / or platinum dehydrogenation catalyst comprises gallium, platinum, or both. The dehydrogenation catalyst may be carried by an alumina, silica-alumina, zirconia, or silica support, and may optionally comprise potassium. In one or more embodiments, the dehydrogenation catalysts may include catalysts disclosed in U. S. Pat. No. 8,669,406, which is incorporated herein by reference in its entirety, such as those including Ga, Cr, and / or Fe based catalysts. According to additional embodiments, Pt based catalysts may be utilized. In one or more embodiments, those catalysts disclosed in EP 0948475B1 and / or WO 2010 / 133565, which are each incorporated herein by reference in its entirety, may be utilized. Additional catalyst embodiments contemplated as suitable for use in the systems and methods described herein include those of U. S. Pat. No.8,669,406, which is incorporated herein by reference in its entirety. Such catalysts may contain relatively low amounts of Cr, such as less than 6%, or approximately 1.5%. However, it should be understood that other suitable dehydrogenation catalysts may be utilized to perform the dehydrogenation reaction.86326-WO-PCT / DOW 86326 WO11

[0034] In one or more embodiments, the dehydrogenation catalyst may exhibit suitable stability when in the presence of steam. As is described herein, the combustion of hydrogen may form steam, which may be in direct contact with the dehydrogenation catalyst. It is contemplated that not all dehydrogenation catalysts are equally effective in steam environments. In one or more embodiments, dehydrogenation catalysts are utilized which maintain a substantial amount of their reactivity and / or selectivity for the dehydrogenation of light alkanes. For example, one or more of the dehydrogenation catalysts utilized in the presently disclosed systems and methods may not deteriorate in alkane conversion and / or selectivity for dehydrogenation more than 25%, more than 20%, more than 15%, more than 10%, more than 5%, or may even have improved alkane conversion and / or selectivity for dehydrogenation when in the presence of steam in amounts consistent with the operation of the presently disclosed systems. In some embodiments, the dehydrogenation catalyst may function with such conversion and / or selectivity when exposed to at least 10 mol. % water (such as from 10 mol. % to 50 mol. % water) for a period of up to, e.g., 120 seconds (the time which the catalyst may be exposed to such conditions, according to some embodiments of the presently disclosed system).

[0035] Now referring to FIG. 1, an example reaction system 100 that may be suitable for use with the methods described herein is schematically depicted. The reaction system 100 may include a moving bed reactor 102 comprising a moving bed. Positioned within the moving bed may be a dehydrogenation zone 110. One or more hydrocarbons may be passed into the dehydrogenation zone 110 via feed stream 112 and a particulate solid may be passed to the dehydrogenation zone 110 via fresh particulate solid feed 116. As described in more detail below, the one or more hydrocarbons may be dehydrogenated to form dehydrogenated products, which may be removed via dehydrogenated products stream 114. Additionally, the spent particulate solid may be removed via spent particulate solid stream 118.

[0036] In the dehydrogenation zone 110, the one or more hydrocarbons of the feed stream 112 may be dehydrogenated to form molecular hydrogen and one or more products. " Dehydrogenation" or “dehydrogenating" refers to a chemical reaction or process wherein the total amount, or relative amount, of hydrogen in a molecule may be reduced. For example, the total number of hydrogens in a hydrocarbon may be reduced, the number of hydrogens per carbon86326-WO-PCT / DOW 86326 WO12in the hydrocarbon may be reduced, or both. The one or more products may leave the dehydrogenation zone 110 via dehydrogenated products stream 114.

[0037] In one or more embodiments, the feed stream 112 may comprise one or more hydrocarbons. In one or more embodiments, the one or more hydrocarbons may comprise an alkyl moiety. As used in the present disclosure a hydrocarbon comprises an “alkyl moiety” if the molecule has at least one carbon-carbon single bond capable of being dehydrogenated to form a carbon-carbon double bond. 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 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.

[0038] In the dehydrogenation zone 110, the feed stream 112 may be dehydrogenated. An example dehydrogenation process where the feed stream comprises ethane is shown in Equation 1.Equation 1: C2H6↔ C2H4+ H2

[0039] As can be seen from Equation 1, the dehydrogenation of the feed stream produces molecular hydrogen. Molecular hydrogen refers to hydrogen either unbound to other atoms or bound only to other hydrogen atoms (e.g., not hydrogen atoms bound to other atoms such as carbon). However, this process may result in the buildup of molecular hydrogen, which may shift the dehydrogenation equilibrium to the left and away from the olefin products. Thus, it may be desirable to remove at least a portion of the molecular hydrogen in order to shift the86326-WO-PCT / DOW 86326 WO13dehydrogenation equilibrium back toward the olefin products. One way to remove at least a portion of the molecular hydrogen is to combust the molecular hydrogen with oxygen from the oxygen-carrier material to form water. In doing so, the concentration of releasable oxygen in the oxygen-carrier material will be reduced.

[0040] In some embodiments, the releasable oxygen of the oxygen-carrier materials may be selective for combusting hydrogen over hydrocarbons. In some embodiments, at least about 60% of the releasable oxygen of the oxygen-carrier material is selective for hydrogen combustion. In other embodiments, at least about 55% of the releasable oxygen of the oxy gen-carrier material is selective for hydrogen combustion.

[0041] In embodiments, when hydrogen (e g., molecular hydrogen) is contacted by the oxy gencarrier material, some of the releasable oxygen is removed from the oxygen-carrier material, thereby producing water. In some embodiments, contacting the hydrogen with the oxygen-carrier material removes from about 1 wt. % to 50 wt. % of the releasable oxygen from the oxygencarrier material. In other embodiments, contacting the hydrogen with the oxygen-carrier material removes from about 10 wt. % to about 50 wt. %, from about 10 wt. % to about 25 wt. %, or from about 25 wt. % to about 50 wt. % of the releasable oxygen from the oxygen-carrier material.

[0042] In further embodiments, when the hydrogen (e.g., molecular hydrogen) is contacted by the oxygen-carrier material, the oxygen-carrier material combusts greater than about 50% of the hydrogen. In other embodiments, when the hydrogen is contacted by the oxygen-carrier material, the oxygen-carrier material combusts from 50 % to 60 %, from 60 % to 70 %, from 70 % to 80 %, from 80 % to 90 %, from 90 % to 95 %, from 95 % to 98 %, from 98 % to 99 %, or any combination of two or more of these ranges of the molecular hydrogen released in the dehydrogenation reaction.

[0043] In the dehydrogenation zone 110 of the moving bed reactor 102, the one or more hydrocarbons of the feed stream and the particulate solid may be in co-current flow or in countercurrent flow. Generally, co-current flow results in greater selectivity and counter-current flow results in greater overall conversion. However, in either case, the particulate solid in the dehydrogenation zone 110 of the moving bed reactor 102 may be contained within the moving bed and not fluidized.86326-WO-PCT / DOW 86326 WO14

[0044] In one or more embodiments, the dehydrogenation zone 110 may operate at a temperature of greater than or equal to 550 °C and less than or equal to 850 °C. In some embodiments, the temperature in the dehydrogenation zone 110 may be from 550 °C to 600 °C, from 600 °C to 650 °C, from 650 °C to 700 °C, from 700 °C to 750 °C, from 750 °C to 800 °C, from 800 °C to 850 °C, or any combination of two or more of these ranges. In other embodiments, the temperature in the dehydrogenation zone 110 may be from 700 °C to 750 °C. Without being bound by any particular theory, it is believed that too low of temperature (e.g., 550 °C or less) may limit the maximum conversion of the hydrocarbon due to equilibrium constraints as well as lowers the rate of dehydrogenation by the thermal and catalytic component. Too low of temperatures may also result in a slow rate of oxygen release from the oxy gen-carrier material and low hydrogen combustion. On the other hand, high temperatures (e.g., greater than 800 °C) may result in thermal degradation of the products produced and may result in a lower product selectivity than is economically feasible. In some embodiments, the primary feed component(s) may be propane, ethylbenzene, and / or butane, and the dehydrogenation zone 110 may operate at a temperature of greater than 600 °C. In additional embodiments, the primary feed component may be ethane, and the dehydrogenation zone 110 may operate at a temperature of at least 625 °C.

[0045] In some embodiments, the dehydrogenation zone 110 may operate at a pressure of at least atmospheric pressure (about 14.7 psia). In some embodiments, the dehydrogenation zone 110 may operate at a pressure of about 500 psia. In other embodiments, the dehydrogenation zone 110 may operate at a pressure from about 4 psia to about 160 psia, from about 20 psia to about 100 psia, or from about 30 psia to about 80 psia.

[0046] In one or more embodiments, the residence time of the one or more hydrocarbons of the feed stream in the dehydrogenation zone 110 may be less than 10 seconds (such less than 9 seconds, less than 8 seconds, less than 7 seconds, less than 6 seconds, less than 5 seconds, less than 4 seconds, or even less than 3 seconds).

[0047] The residence time of the particulate solid in the dehydrogenation zone 110 may typically vary from 0.5 seconds (sec) to 360 sec. In other embodiments, the residence time of the particulate solid may be from about 0.5 sec to 200 sec, such as from 0.5 sec to 1 sec, from 1 sec to 2 sec, from 2 sec to 5 sec, from 5 sec to 10 sec, from 10 sec to 20 sec, from 20 sec to 4086326-WO-PCT / DOW 86326 WO15sec, from 40 sec to 60 sec, from 60 sec to 80 sec, from 80 sec to 100 sec, from 100 sec to 125 sec, from 125 sec to 150 sec, from 150 sec to 175 sec, from 175 sec to 200 sec, or an combination of two or more of these ranges.

[0048] In some embodiments, the weight ratio of the particulate solid to the feed stream entering the dehydrogenation zone 110 may range from 5 to 150 on a weight to weight (w / w) basis. In some embodiments, the ratio may range from 5 to 10, 10 to 20, 20 to 40, 40 to 60, 60 to 80, 80 to 100, 100 to 125, 125 to 150, 10 to 40, 12 to 36, 12 to 24, or any combination of two or more of these ranges.

[0049] In additional embodiments, the flux of the particulate solid entering the dehydrogenation zone 110 may be from 1 pound per square foot-second (lb / ft2-s) (about 4.89 kg / m2-s) to 300 lb / ft2-s (to about 97.7 kg / m2-s), such as from 1-20 lb / ft2-s, 20 to 40 lb / ft2-s, 40 to 60 lb / ft2-s, 60 to 80 lb / ft2-s, 80 to 100 lb / ft2-s, 100 to 150 lb / ft2-s, 150 to 200 lb / ft2-s, 200 to 250 lb / ft2-s, 250 to 300 lb / ft2-s, or any combination of two or more of these ranges.

[0050] Still referring to dehydrogenation zone 110, the dehydrogenation zone 110 may be subdivided into two or more sections, such as a first section 120 and a second section 130. Each of the sections (e.g., first section 120 and second section 130) may refer to portions of the same moving bed of the moving bed reactor 102. Each of the sections (e.g., first section 120 and second section 130) of the moving bed may be separated by one or more void spaces, solid / vapor separation devices, mixing sections, or other apparatuses. Each of the sections (e.g., the first section 120 and the second section 130) may operate under the same conditions described herein for the dehydrogenation zone 110 generally. In some embodiments, The first section 120 and the second section 130 may operate under substantially the same conditions (e.g., any property (such as temperature or pressure) in the second section 130 may be within 10 % of its respective value in the first section 120).

[0051] In the first section 120, a portion of the one or more hydrocarbons of the feed stream 112 may be dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen may be reacted with oxygen from the oxygen-carrier material to form water. In some embodiments, the first section 120 may have an average humidity of from 0 % to 50 %, such as from 0 % to 5 %, from 5 % to 10 %, from 10 % to 15 %, from 15 % to 20 %, from 20 % to 25 %, from 25 % to 30 %, from 30 % to 35 $, from86326-WO-PCT / DOW 86326 WO1635 % to 40 %, from 40 % to 45 %, from 45 % to 50 %, or any combination of two or more of these ranges.

[0052] At least a portion of the water, unreacted hydrocarbons, and dehydrogenated products from the first section 120 may be separated into a water-rich fluid stream 122. The water-rich fluid stream 122 may have a water concentration of from 0 % to 50 %, such as from 0 % to 5 %, from 5 % to 10 %, from 10 % to 15 %, from 15 % to 20 %, from 20 % to 25 %, from 25 % to 30 %, from 30 % to 35 $, from 35 % to 40 %, from 40 % to 45 %, from 45 % to 50 %, or any combination of two or more of these ranges. The water-rich fluid stream 122 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 water generated in the first section 120.

[0053] The water-rich fluid stream 122 comprising at least water, unreacted hydrocarbons, and dehydrogenated products may be passed to a water removal device 124. Water removal device 124 may refer to any device suitable for separating water from a stream. In some embodiments, the water removal device may refer to a condenser, chiller, absorber, heat exchanger, flash column, or the like. In some specific embodiments, water removal device 124 may refer to a chiller. The water removed by water removal device 124 may be disposed of via water outlet stream 128.

[0054] The unreacted hydrocarbons and dehydrogenated products, along with any unseparated water, from water removal device 124 may be passed back to the dehydrogenation zone 110 of moving bed reactor 102 via water-reduced fluid stream 126. Water-reduced fluid stream 126 may comprise less than 50 wt. %, less than 40 wt. %, less than 20 wt. %, less than 10 wt. %, less than 5 wt. % or even less than 1 wt. % of water. In some embodiments, water-reduced fluid stream 126 may comprise at least 80 wt. %, at least 90 wt. %, at least 95 wt. %, or even at least 99 wt. % of the combined weight of unreacted hydrocarbons and dehydrogenated products.

[0055] The water-reduced fluid stream 126 may be passed from the water removal device 124 to the second section 130. Additionally, all, or a portion, of the particulate solid may pass from the first section 120 to the second section 130. In some embodiments, the particulate solid may pass from the first section 120 to the second section 130 without leaving the moving bed reactor 102 and / or without leaving a single moving bed. Additionally, a portion of the water, unreacted hydrocarbons, and dehydrogenated products from the first section 120 may pass directly (e.g.,86326-WO-PCT / DOW 86326 WO17not through the water removal device 124) from the first section 120 to the second section 130. In some embodiments, the portion of the water, unreacted hydrocarbons, and dehydrogenated products may pass from the first section 120 to the second section 130 without leaving the moving bed of the moving bed reactor 102.

[0056] In the second section 130, a portion of the hydrocarbons of the feed stream may be dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen is reacted with oxygen from the oxygen-carrier material to form water. As described hereinabove, the second section 130 may operate under the conditions generally given for the dehydrogenation zone 110. It should be noted that water in the second section 130 may be passed from the first section 120 to the second section 130 through the moving bed, passed through the water-reduced stream 126 to the second section 130, or produced in place in the second section 130 via the reaction of molecular hydrogen with water. In some embodiments, a humidity in the second section 130, may be from 0 % to 50 %, such as from 0 % to 5 %, from 5 % to 10 %, from 10 % to 15 %, from 15 % to 20 %, from 20 % to 25 %, from 25 % to 30 %, from 30 % to 35 $, from 35 % to 40 %, from 40 % to 45 %, from 45 % to 50 %, or any combination of two or more of these ranges. %.

[0057] Still referring to FIG. 1, the dehydrogenated products may exit the dehydrogenation zone 110 of the moving bed reactor 102 via dehydrogenated products stream 114. Dehydrogenated products stream 114 may be further processed such as by one or more subsequent separation steps or further reacted. It is contemplated that dehydrogenated products stream 114 may be utilized as a feed for another reactor system or sold as a chemical product. Before sale or use as a feed, the dehydrogenated products stream 114 may be subjected to one or more separations or other processing steps. In some embodiments, at least a portion the water produced from the combustion of the molecular hydrogen may be removed from dehydrogenated products stream 114 and the one or more products utilizing a condenser.

[0058] As described above, in some embodiments, dehydrogenated products stream 114 may comprise one or more products. In one or more embodiments, the one or more products may comprise one or more olefinic compounds. 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, but86326-WO-PCT / DOW 86326 WO18ethylbenzene 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. In one or more embodiments, the one or more olefinic compounds may comprise one or more of ethylene, propylene, butylene, or styrene. In some embodiments, the one or more products 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 ethylene. In additional embodiments, the one or more products 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 propylene. In additional embodiments, the one or more products 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 butylene. In additional embodiments, the one or more products 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 styrene. In additional embodiments, the one or more products 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 one or more of ethylene, propylene, butylene, and styrene. In some embodiments, the dehydrogenated products stream 114 may comprise at least 50 wt. %, at least 75 wt. %, at least 80 wt. %, at least 85 wt. %, at least 90 wt. %, at least 95 wt. %, at least 98 wt. %, or even at least 99 wt. % of the one or more products.

[0059] Still referring to FIG. 1, the particulate solid may exit the moving bed reactor 102 via spent particulate solid stream 118. The oxygen-carrier material of the particulate solid in the spent particulate solid stream 118 may be in a reduced state, having less oxygen than the with the oxygen-carrier material in the fresh particulate solid feed 116. Additionally, the particulate solid may be coked, fouled, or otherwise deactivated.

[0060] The particulate solid may be subjected to one or more regeneration steps generally known to those skilled in the art and not depicted in the figures herein. For example, the particulate solid may be subjected to one or more combustion steps to raise the temperature of the particulate solid, remove coke, and / or partially deactivate to oxygen-carrier material (e.g., to prevent the oxygen-carrier material from being overly active and reducing selectivity). Additionally, the particulate solid may be subjected to one or more oxygen treatment steps to oxidize the oxy gen-carrier material. In some embodiments, the particulate solid may be separated86326-WO-PCT / DOW 86326 WO19and different portions may be subjected to different regeneration treatments. However regenerated, the particulate solid, or portions thereof, may be recycled back to the moving bed reactor 102 via fresh particulate solid feed 116.

[0061] Referring now to FIG. 2, another reaction system 200 is depicted. The reaction system 200 is similar or identical to the reaction system 100 of FIG. 1, except where described otherwise. In particular, in the reaction system 200 of FIG. 2, the dehydrogenation zone 210 may be divided into additional sections (e.g., a third section 240 and a fourth section 250 may be present). In between any, or each, of the sections a water removal device may be present.

[0062] In embodiments, feed stream 212, dehydrogenated products stream 214, fresh particulate solid 216, spent particulate solid stream 218, moving bed reactor 202, dehydrogenation zone 210, first section 220, second section 230, water-rich fluid stream 222, water removal device 224, water-reduced fluid stream 226, and water outlet stream 228, and second section 230 may be the same or similar to their respective components in reaction system 100.

[0063] However, after second section 230, rather than exiting the moving bed reactor, at least a portion of the water, unreacted hydrocarbons, and dehydrogenated products from the second section 230 may be separated into a second water-rich fluid stream 232. The second water-rich fluid stream 232 may have a water concentration of from 0 % to 50 %, such as from 0 % to 5 %, from 5 % to 10 %, from 10 % to 15 %, from 15 % to 20 %, from 20 % to 25 %, from 25 % to 30 %, from 30 % to 35 $, from 35 % to 40 %, from 40 % to 45 %, from 45 % to 50 %, or any combination of two or more of these ranges.. The second water-rich fluid stream 232 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 water generated in the second section 230.

[0064] The second water-rich fluid stream 232 comprising at least water, unreacted hydrocarbons, and dehydrogenated products may be passed to a second water removal device 234. Second water removal device 234 may refer to any device suitable for separating water from a stream. Second water removal device 234 may be the same type of device as used for water removal device 124 or a different type of water removal device. In some embodiments, the second water removal device 234 may refer to a condenser, chiller, or absorber. In some86326-WO-PCT / DOW 86326 WO20specific embodiments, second water removal device 234 may refer to a chiller. The water removed by second water removal device 234 may be disposed of via second water stream 238.

[0065] The unreacted hydrocarbons and dehydrogenated products, along with any unseparated water, from second water removal device 234 may be passed into third section 240 of the dehydrogenation zone 210 of moving bed reactor 202 via second water-reduced fluid stream 236. Second water-reduced fluid stream 236 may comprise less than 50 wt. %, less than 40 wt. %, less than 20 wt. %, less than 10 wt. %, less than 5 wt. % or even less than 1 wt. % of water. In some embodiments, second water-reduced fluid stream 236 may comprise at least 80 wt. %, at least 90 wt. %, at least 95 wt. %, or even at least 99 wt. % of the combined weight of unreacted hydrocarbons and dehydrogenated products.

[0066] The second water-reduced fluid stream 236 may be passed from the second water removal device 234 to the third section 240. Additionally, all, or a portion, of the particulate solid may pass from the second section 230 to the third section 240. In some embodiments, the particulate solid may pass from the second section 230 to the third section 240 without leaving the moving bed reactor 102 and / or without leaving a single moving bed. Additionally, a portion of the water, unreacted hydrocarbons, and dehydrogenated products from the second section 230 may pass directly (e.g., not through the water removal device) from the second section 230 to the third section 240. In some embodiments, the portion of the water, unreacted hydrocarbons, and dehydrogenated products may pass from the second section 230 to the third section 240 without leaving the moving bed of the moving bed reactor 202.

[0067] In the third section 240, a portion of the hydrocarbons of the feed stream may be dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen may be reacted with oxygen from the oxygen-carrier material to form water. As described hereinabove, the third section 240 may operate under the conditions generally given for the dehydrogenation zone 110. In some embodiments, a humidity in the third section 240, may be from 0 % to 50 %, such as from 0 % to 5 %, from 5 % to 10 %, from 10 % to 15 %, from 15 % to 20 %, from 20 % to 25 %, from 25 % to 30 %, from 30 % to 35 $, from 35 % to 40 %, from 40 % to 45 %, from 45 % to 50 %, or any combination of two or more of these ranges.86326-WO-PCT / DOW 86326 WO21

[0068] At least a portion of the water, unreacted hydrocarbons, and dehydrogenated products formed in the third section 240 may be separated into a third water-rich fluid stream 242. The third water-rich fluid stream 242 may have a water concentration of from 0 % to 50 %, such as from 0 % to 5 %, from 5 % to 10 %, from 10 % to 15 %, from 15 % to 20 %, from 20 % to 25 %, from 25 % to 30 %, from 30 % to 35 $, from 35 % to 40 %, from 40 % to 45 %, from 45 % to 50 %, or any combination of two or more of these ranges. The third water-rich fluid stream 242 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 water generated in the third section 240.

[0069] The third water-rich fluid stream 242 comprising at least water, unreacted hydrocarbons, and dehydrogenated products may be passed to a third water removal device 244. Third water removal device 244 may refer to any device suitable for separating water from a stream. Third water removal device 244 may be the same or different from water removal device 224 and second water removal device 234. In some embodiments, the third water removal device 244 may refer to a condenser, chiller, or absorber. In some specific embodiments, third water removal device 244 may refer to a chiller. The water removed by third water removal device 244 may be disposed of via third water stream 248.

[0070] The unreacted hydrocarbons and dehydrogenated products, along with any unseparated water, from third water removal device 244 may be passed back to the dehydrogenation zone 210 of moving bed reactor 202 via third water-reduced fluid stream 246. Third water-reduced fluid stream 246 may comprise less than 50 wt. %, less than 40 wt. %, less than 20 wt. %, less than 10 wt. %, less than 5 wt. % or even less than 1 wt. % of water. In some embodiments, third water-reduced fluid stream 246 may comprise at least 80 wt. %, at least 90 wt. %, at least 95 wt. %, or even at least 99 wt. % of the combined weight of unreacted hydrocarbons and dehydrogenated products.

[0071] The third water-reduced fluid stream 246 may be passed from the third water removal device 244 to the fourth section 250. Additionally, all, or a portion, of the particulate solid may pass from the third section 240 to the fourth section 250. In some embodiments, the particulate solid may pass from the third section 240 to the fourth section 250 without leaving the moving bed reactor 202 and / or without leaving a single moving bed. Additionally, a portion of the water,86326-WO-PCT / DOW 86326 WO22unreacted hydrocarbons, and dehydrogenated products from the third section 240 may pass directly (e.g., not through the water removal device) from the third section 240 to the fourth section 250. In some embodiments, the portion of the water, unreacted hydrocarbons, and dehydrogenated products may pass from the third section 240 to the fourth section 250 without leaving the moving bed of the moving bed reactor 202.

[0072] In the fourth section 250, a portion of the hydrocarbons of the feed stream may be dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen may be reacted with oxygen from the oxygen-carrier material to form water. As described hereinabove, the fourth section 250 may operate under the conditions generally given for the dehydrogenation zone 110. In some embodiments, a humidity in the fourth section 250, may be from 0 % to 50 %, such as from 0 % to 5 %, from 5 % to 10 %, from 10 % to 15 %, from 15 % to 20 %, from 20 % to 25 %, from 25 % to 30 %, from 30 % to 35 $, from 35 % to 40 %, from 40 % to 45 %, from 45 % to 50 %, or any combination of two or more of these ranges.

[0073] After fourth section 250, particulate solid may exit the moving bed reactor 202 via spent particulate solid stream 218. Unreacted hydrocarbons and dehydrogenated products may exit the moving bed reactor 202 via dehydrogenated products stream 214. Spent particulate solid stream 218 and dehydrogenated products stream 214 may be the same or similar to spent particulate solid stream 118 and dehydrogenated products stream 114.

[0074] Alternatively, more or fewer sections and water removal devices than described hereinabove may be present before the reactants exit the moving bed reactor. Some embodiments of the process described hereinabove may be generalized to a moving bed reactor having “n” sections, “n” (the number of sections) may be all integers from 2 to z, such as all integers from 3 to z, all integers from 4 to z, or all integers from 5 to x. “z” is an integer greater than or equal to 2 (e.g., Z may be 2, 3, 4, 5, 6, 7, 8, 9, 10, or more than 10). Thus, when 4 sections are present, “Z” is 4 and “n” is 2, 3, and 4.

[0075] The method may comprise passing an (n-l)thwater-rich fluid stream from the (n-l)thsection into an (n-l)thwater removal device. The (n-l)thwater-rich fluid stream may comprise water, unreacted hydrocarbons, and dehydrogenated products. The (n-l)thwater-rich fluid stream may be as described for water-rich fluid stream 122.86326-WO-PCT / DOW 86326 WO23

[0076] In the (n-l)thwater removal device, a portion, or all, of the water may be removed from the (n-l)thwater-rich fluid stream to form a (n-l)thwater-reduced fluid stream. The (n-l)thwater removal device may be as described for water removal device 124. The (n-l)thwater-reduced fluid stream may be as described for water-reduced fluid stream 126. The (n-l)thwater-reduced fluid stream may pass into the nthsection.

[0077] The method may then comprise passing the portion of the water, unreacted hydrocarbons, and dehydrogenated products that do not pass through the (n-l)thwater removal device to the nthsection. In the nthsection, a portion of the hydrocarbons of the feed stream may be dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen may be reacted with oxygen from the oxygen-carrier material to form water. Thus, the process described herein may be extrapolated to any number of sections and water removal devices.

[0078] Referring now to FIG. 3, another reaction system 300 is depicted. The reaction system 300 is similar or identical to the reaction systems 100 of FIG. 1 and 200 of FIG. 2, except where described otherwise. In particular, in the reaction system 300 of FIG. 3, the configuration of the reaction zones is depicted to specifically show expanded sections 321, 331, and standpipe reaction sections 333, 343. As mentioned hereinabove, the expanded sections 321, 331 may allow for the removal of gaseous components (e.g., the water-rich fluid streams 322, 332) from the moving bed 310. Additionally, the reincorporation of the water-reduced fluid streams 326, 336 is depicted in FIG. 3 as being into the standpipe reaction sections 323, 333. It is noted that the embodiments of FIG. 3 represent one non-limiting embodiment and alternate configurations are contemplated.

[0079] According to one or more aspects:

[0080] Aspect 1. A method for dehydrogenating hydrocarbons, the method comprising: passing a feed stream and a particulate solid into a moving bed reactor, the feed stream comprising one or more hydrocarbons, the particulate solid comprising an oxygen-carrier material, and wherein: the moving bed reactor comprises a dehydrogenation zone that comprises a first section and a second section, wherein the particulate solids move from the first section to the second section through the dehydrogenation zone; in the first section, a portion of the one or more hydrocarbons of the feed stream are dehydrogenated to form molecular hydrogen and one or more86326-WO-PCT / DOW 86326 WO24dehydrogenated products, and at least a portion of the molecular hydrogen is reacted with oxygen from the oxygen-carrier material to form water; passing a water-rich fluid stream from the first section into a water removal device, the water-rich fluid stream comprising water, unreacted hydrocarbons, and dehydrogenated products, wherein in the water removal device a portion or all of the water is removed from the water-rich fluid stream to form a water-reduced fluid stream; passing the water-reduced fluid stream into the second section; and passing the portion of the water, unreacted hydrocarbons, and dehydrogenated products that do not pass through the water removal device to the second section, wherein in the second section a portion of the hydrocarbons of the feed stream are dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen is reacted with oxygen from the oxygen-carrier material to form water.

[0081] Aspect 2. The method of aspect 1, wherein the dehydrogenation zone further comprises n sections, n is all integers from 3 to z, and z is greater than or equal to 3, the method further comprising: passing an (n-l)thwater-rich fluid stream from the (n-l)thsection into an (n-l)thwater removal device, the (n-l)thwater-rich fluid stream comprising water, unreacted hydrocarbons, and dehydrogenated products, wherein in the (n-l)thwater removal device a portion or all of the water is removed from the (n-l)thwater-rich fluid stream to form a (n-l)thwater-reduced fluid stream; passing the (n-l)thwater-reduced fluid stream into the nthsection; and passing the portion of the water, unreacted hydrocarbons, and dehydrogenated products that do not pass through the water removal device from the (n-l)thsection to the nthsection, wherein in the nthsection a portion of the hydrocarbons of the feed stream are dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen is reacted with oxygen from the oxy gen-carrier material to form water.

[0082] Aspect 3. The method of aspect 1 or 2, wherein the water-reduced fluid stream comprises from 0 to 20 wt. % of water.

[0083] Aspect 4. The method any one of aspects 1 to 3, wherein a humidity in each of the first section, the second section, and optionally n sections, is from 0 % to 50 %.

[0084] Aspect 5. The method any one of aspects 1 to 4, wherein the particulate solid material further comprises a dehydrogenation catalyst.86326-WO-PCT / DOW 86326 WO25

[0085] Aspect 6. The method of any one of aspects 1 to 5, wherein the particulate solid material consists of the oxygen-carrier material.

[0086] Aspect 7. The method of any one of aspects 1 to 6, wherein the oxy gen-carrier material has dehydrogenation catalytic functionality.

[0087] Aspect 8. The method of any one of aspects 1 to 7, wherein the feed stream and the particulate solid are in co-current flow in the dehydrogenation zone.

[0088] Aspect 9. The method of any one of aspects 1 to 8, wherein the particulate solids move downward though the moving bed reactor under the force of gravity and are not fluidized.

[0089] Aspect 10. The method of any one of aspects 1 to 9, wherein the particulate solid exhibits Geldart D properties in the moving bed reactor.

[0090] Aspect 11. The method of any one of aspects 1 to 10, wherein the particulate solid further comprises one or more alkali / alkaline earth metals.

[0091] Aspect 12. The method of any one of aspects 1 to 11, wherein the one or more hydrocarbons comprise an alkyl moiety.

[0092] Aspect 13. The method of any one of aspects 1 to 12, wherein the one or more products comprise one or more olefinic compounds.

[0093] Aspect 14. The method of any one of aspects 1 to 13, wherein the one or more hydrocarbons comprise ethane and the one or more products comprise ethylene.EXAMPLES

[0094] The described embodiments will be further clarified by the following examples and comparative examples.

[0095] A catalyst was made by first preparing an impregnated Si-ZrO₂ support, and then by impregnating the Si-ZrO₂ support with chromium. First, a monoclinic ZrO₂ support (NORPRO SZ31164 3 mm extrudates, BET = 100 m2 / g, pore volume determined by DI water 0.4 mL / g) was crushed and sieved to 40-80 mesh size. Then, 5 g of the ZrO₂ support was impregnated with 2 mL of tetraethylorthosilicate (TEOS) until the impregnation solution was no longer drawn into the pores of the support and the impregnation solution was homogenously distributed over the support. The material was dried and calcined under air in a box oven using the following temperature program: room temperature to 177 °C at 5 deg / min, dwell 2 h, 177 °C to 750 °C at86326-WO-PCT / DOW 86326 WO265 deg / min, dwell 1 h, cool down to room temperature. The support was sieved after calcination to remove fine particles smaller than 80 mesh. Next, 2 g of Si-ZrO₂ support was impregnated with 0.8 mL of 1 M Cr (III) nitrate nonahydrate solution in DI water until the impregnation solution was no longer drawn into the pores of the support and the impregnation solution was homogenously distributed over the support. The chromium impregnated Si-ZrO₂ support was dried and calcined under air in a box oven using the following temperature program: room temperature to 177 °C at 5 deg / min, dwell 2 h, 177 to 750 °C at 5 deg / min, dwell 1 h, cool down to room temperature. The catalyst was sieved after calcination to remove fine particles smaller than 80 mesh. The as-prepared catalyst contained: 1.99 wt. % Cr, 68.1 wt. % Zr, 2.45 wt. % Hf, 0.884 wt. % Si, O - balance according to X-ray Fluorescence (XRF) measurement. XRF data was collected at room temperature (RT) with a PANalytical PW4400 spectrometer using an X-ray tube with a rhodium anode.

[0096] The catalyst performance was assessed by loading 0.3 g of catalyst in a fixed bed reactor, while flowing 75 seem of total gas flow through it. The gas stream composed of 60 vol. % ethane (and balance N2) in absence of water co-feed, whereas 20 vol. % of N2was replaced with water in the steam co-feed experiments such that the total ethane partial pressure remains unchanged. The reactive gas stream was fed over the catalyst bed for 24s with the GC injection at the end of 24s to capture the product stream composition. Once subjected to the reactive gas feed, the catalyst was regenerated for 15 min in air and this reaction-regeneration cycle was repeated 3 times under each operating temperature (650 °C, 700 °C, and 750 °C) and ambient pressure. The results are shown in Table 1 below.Table 1Temp Steam (vol. Conversion Ethylene selectivity COx& CH4selectivity (°C) %) (%) (%) (%)EX-1 650 0 20 97 2EX- 650 20 11 95 51SEX-2 700 0 29 95 286326-WO-PCT / DOW 86326 WO27EX- 700 20 22 92 828EX-3 750 0 37 94 3.5EX- 750 20 37 88 1238

[0097] Across temperatures, it can be seen that in presence of steam there is a loss of ethylene selectivity while selectivity towards reforming products (COx and CH4) increases. Without being limited by theory, it is believed that this can be attributed to catalytic reforming of ethane / ethylene in presence of steam. Moreover, presence of water is also believed to create an inhibition effect, which may manifest in the form of lower ethane conversion, especially at lower temperatures.

[0098] 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.

[0099] 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.

[0100] 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 that86326-WO-PCT / DOW 86326 WO28may 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.

[0101] 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.

[0102] 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.

[0103] 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 present technology, 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.”

[0104] In some embodiments, chemicals or chemical streams are described as “passing” from one system unit or portion of a system unit to another. As described herein, such passing may include direct passing or indirect passing. For example, when passing from “unit A” to “unit B”, direct passing has no intermediate destination between unit A and unit B (i.e., directly through a pipe or other transport passage), and indirect passing may include one or more intermediate destinations between unit A and unit B. For example, a stream passing from unit A to unit B may passed through, without limitation, a heat exchanger, treatment device, etc.

[0105] 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 multiple86326-WO-PCT / DOW 86326 WO29ranges for a quantitative value are provided, these ranges may be combined to form a broader range, which is contemplated in the embodiments described herein.

Claims

86326-WO-PCT / DOW 86326 WO30CLAIMS1. A method for dehydrogenating hydrocarbons, the method comprising:passing a feed stream and a particulate solid into a moving bed reactor, the feed stream comprising one or more hydrocarbons, the particulate solid comprising an oxygen-carrier material, and wherein:the moving bed reactor comprises a dehydrogenation zone that comprises a first section and a second section, wherein the particulate solids move from the first section to the second section through the dehydrogenation zone;in the first section, a portion of the one or more hydrocarbons of the feed stream are dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen is reacted with oxygen from the oxygen-carrier material to form water;passing a water-rich fluid stream from the first section into a water removal device, the water-rich fluid stream comprising water, unreacted hydrocarbons, and dehydrogenated products, wherein in the water removal device a portion or all of the water is removed from the water-rich fluid stream to form a water-reduced fluid stream;passing the water-reduced fluid stream into the second section; andpassing the portion of the water, unreacted hydrocarbons, and dehydrogenated products that do not pass through the water removal device to the second section, wherein in the second section a portion of the hydrocarbons of the feed stream are dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen is reacted with oxygen from the oxygen-carrier material to form water.

2. The method of claim 1, wherein the dehydrogenation zone further comprises n sections, n is all integers from 3 to z, and z is greater than or equal to 3, the method further comprising:passing an (n-l)thwater-rich fluid stream from the (n-l)thsection into an (n-l)thwater removal device, the (n-l)thwater-rich fluid stream comprising water, unreacted hydrocarbons, and dehydrogenated products, wherein in the (n-l)thwater removal device a portion or all of the water is removed from the (n-l)thwater-rich fluid stream to form a (n-l)thwater-reduced fluid stream;86326-WO-PCT / DOW 86326 WO31passing the (n-l)thwater-reduced fluid stream into the nthsection; andpassing the portion of the water, unreacted hydrocarbons, and dehydrogenated products that do not pass through the water removal device from the (n-l)thsection to the nthsection, wherein in the nthsection a portion of the hydrocarbons of the feed stream are dehydrogenated to form molecular hydrogen and one or more dehydrogenated products, and at least a portion of the molecular hydrogen is reacted with oxygen from the oxygen-carrier material to form water.

3. The method of claim 1 or 2, wherein the water-reduced fluid stream comprises from 0 to 20 wt. % of water.

4. The method any one of claims 1 to 3, wherein a humidity in each of the first section, the second section, and optionally n sections, is from 0 % to 50 %.

5. The method any one of claims 1 to 4, wherein the particulate solid material further comprises a dehydrogenation catalyst.

6. The method of any one of claims 1 to 5, wherein the particulate solid material consists of the oxygen-carrier material.

7. The method of any one of claims 1 to 6, wherein the oxygen-carrier material has dehydrogenation catalytic functionality.

8. The method of any one of claims 1 to 7, wherein the feed stream and the particulate solid are in co-current flow in the dehydrogenation zone.

9. The method of any one of claims 1 to 8, wherein the particulate solids move downward though the moving bed reactor under the force of gravity and are not fluidized.

10. The method of any one of claims 1 to 9, wherein the particulate solid exhibits Geldart D properties in the moving bed reactor.86326-WO-PCT / DOW 86326 WO3211. The method of any one of claims 1 to 10, wherein the particulate solid further comprises one or more alkali / alkaline earth metals.

12. The method of any one of claims 1 to 11, wherein the one or more hydrocarbons comprise an alkyl moiety.

13. The method of any one of claims 1 to 12, wherein the one or more products comprise one or more olefinic compounds.

14. The method of any one of claims 1 to 13, wherein the one or more hydrocarbons comprise ethane and the one or more products comprise ethylene.

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