Catalysts for dehydrogenation processes

Abstract

A method for dehydrogenating one or more hydrocarbons and regenerating and reactivating the catalyst composition includes contacting a first gaseous stream containing a first hydrocarbon, such as propane, with a catalyst composition at a first temperature in a dehydrogenation reactor, thereby producing a first dehydrogenated hydrocarbon, such as propylene, and a deactivated catalyst composition, combusting at least one fuel gas and coke over the deactivated catalyst at a second temperature in the presence of oxygen, thereby producing a heated catalyst composition, and reactivating the catalyst in the presence of oxygen. The second temperature is 50° C. to 200° C. higher than the first temperature. Catalyst compositions are also described, including additional precious metals, such as gallium, platinum, and palladium.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. Provisional Patent Application No. 63 / 238,940, filed August 31, 2021, and entitled "CATALYSTS FOR DEHYDROGENATION PROCESS," which is incorporated by reference in its entirety herein.

[0002] FIELD OF THEINVENTION FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate generally to the dehydrogenation of hydrocarbons, and specifically to methods for dehydrogenating hydrocarbons and for regenerating and reactivating dehydrogenation catalyst systems. [Background technology]

[0003] Light olefins such as ethylene can be used as a base material to produce many different materials, such as polyethylene, vinyl chloride, and ethylene oxide, which can be used in product packaging, construction, and textiles. As a result of this utility, the global demand for light olefins is increasing. Suitable processes for producing light olefins generally depend on a given chemical feedstock and include, for example, fluidized catalytic dehydrogenation (FCDh) processes. Summary of the Invention

[0004] Generally, in the FCDh process, a hydrocarbon-containing feedstock and a fluidized catalyst are introduced into the reactor section of the FCDh system, the hydrocarbon-containing feedstock contacts the catalyst, and the resulting mixture flows through the reactor section to undergo dehydrogenation, thereby producing dehydrogenated hydrocarbons and a deactivated catalyst composition. The catalyst composition can be separated from the dehydrogenated hydrocarbons and sent to the catalytic processing section of the FCDh system. Typically, the heat required for dehydrogenation in the FCDh process is provided primarily by the combustion of combustion fuels, such as coke deposited on the catalyst and / or auxiliary fuels, in the catalytic processing section. Specifically, the catalyst, which is heated by the combustion of the combustion fuel in the catalytic processing section, transfers heat to the reactor section. In order to combust the combustion fuel at a reasonable temperature, the catalyst is relied upon to provide combustion activity. An efficient FCDh system allows for rapid changes in products through changes in the composition of the hydrocarbon-containing feedstock. However, the composition of the feedstock can affect the amount of heat required to perform the dehydrogenation. For example, using isothermal conditions for ease of comparison, the dehydrogenation of isobutane requires a temperature of about 570° C., the dehydrogenation of propane requires a temperature of about 630° C., and the dehydrogenation of ethane requires a temperature of about 770° C. to achieve 50% conversion of each feedstock. The catalyst systems and methods for dehydrogenating hydrocarbons of the present disclosure may increase the operational flexibility of the reactor systems including the catalysts used therein, such that the dehydrogenation of a variety of feedstocks may be achieved using the same reactor system. This is accomplished, at least in part, by the utilization of the catalysts described herein that include gallium, platinum, and at least one other precious metal.

[0005] According to an embodiment, a method for dehydrogenation of one or more hydrocarbons and regeneration and reactivation of a catalyst composition includes contacting a first gaseous stream containing a first hydrocarbon with a catalyst composition at a first temperature in a dehydrogenation reactor, thereby producing a first dehydrogenated hydrocarbon and a deactivated catalyst composition, combusting at least one fuel gas and coke over the deactivated catalyst at a second temperature in the presence of oxygen, thereby producing a heated catalyst composition, and reactivating the catalyst in the presence of oxygen. The second temperature is 50°C to 200°C higher than the first temperature. The catalyst composition includes an active metal including gallium, a support, and a promoter including platinum and at least one precious metal selected from the group consisting of ruthenium, rhodium, palladium, rhenium, iridium, and combinations of two or more thereof. The weight ratio of the total amount of the second precious metal to platinum is 0.05 to 1.5.

[0006] According to an embodiment, the catalyst composition includes an active metal including gallium, a support, and a promoter including platinum and at least one precious metal selected from the group consisting of ruthenium, rhodium, palladium, rhenium, iridium, and combinations of two or more thereof. The weight ratio of the total amount of the second precious metal to platinum is 0.05 to 1.5.

[0007] The ability to change the feedstock for the dehydrogenation reactor has been found to be enhanced when using a dehydrogenation catalyst composition comprising an active metal composition and a promoter, the promoter comprising platinum and at least one additional precious metal. The ability to change the feedstock may be further enhanced by including an additional precious metal and platinum at a weight ratio of the additional precious metal to the platinum of 0.05 to 1.5. In addition, the catalyst composition described herein allows for regeneration of the catalyst composition at lower temperatures. As a result, regeneration may be carried out at temperatures 50° C. to 200° C. higher than the temperature at which the dehydrogenation is carried out. This, in turn, may further enhance the ability to change the feedstock.

[0008] It should be understood that both the foregoing general description and the following detailed description present embodiments of the technology and are intended to provide an overview or framework for understanding the nature and characteristics of the claimed technology. The accompanying drawings are included to provide a further understanding of the technology, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments and, together with the description, serve to explain the principles and operation of the technology. Additionally, the drawings and description are intended to be merely illustrative and are not intended to limit the scope of the claims in any manner.

[0009] Additional features and advantages of the described embodiments will be set forth in the detailed description which follows, and in part will become readily apparent to those skilled in the art from the description, or may be learned by practice of the described embodiments, including the following detailed description and drawings and claims. [Brief description of the drawings]

[0010] The following detailed description of certain embodiments of the present disclosure can be best understood when read in conjunction with the following drawings, in which like structure is indicated with like reference numerals and in which: [Figure 1] 1 illustrates a schematic depiction of a reactor system according to one or more embodiments of the present disclosure.

[0011] Reference will now be made in more detail to various embodiments, some of which are illustrated in the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] According to one or more embodiments described herein, the methods and catalysts may be used, for example, for the dehydrogenation of a hydrocarbon-containing feedstock using a flow reactor system. The catalyst may become deactivated and require regeneration and reactivation, including combustion of fuel gas and / or coke deposits on the catalyst. Various embodiments will now be discussed in more detail.

[0013] As used in this disclosure, the term "fluidized reactor system" refers to a reactor system in which one or more reactants contact a catalyst in different parts of the system in a fluidized regime, such as a bubble regime, a slug flow regime, a turbulent flow regime, a fast fluidized regime, a pneumatically entrained regime, or a combination thereof. For example, in a fluidized reactor system, a chemical feedstock containing one or more reactants can be contacted with a circulating catalyst at an operating temperature to carry out a continuous reaction and produce an effluent.

[0014] As used in this disclosure, the term "deactivated catalyst" or "spent catalyst" refers to a catalyst that has reduced catalytic activity resulting from coke accumulation and / or loss of catalytically active sites. The terms "catalytic activity" and "catalyst activity" refer to the extent to which a catalyst is capable of catalyzing reactions taking place in a reactor system.

[0015] As used in this disclosure, the terms "catalyst reactivation" and "reactivating a catalyst" refer to treating a deactivated catalyst to restore at least a portion of its catalytic activity to produce a reactivated catalyst. The deactivated catalyst may be reactivated by, but is not limited to, restoring catalyst acidity, oxidizing the catalyst, other reactivation processes, or combinations thereof.

[0016] As mentioned above, the heat and temperature requirements for dehydrogenation depend at least in part on the predominant hydrocarbon in the gaseous hydrocarbon-containing stream. For example, the reaction heat required for the dehydrogenation of isobutane is about 15% lower than that required for the dehydrogenation of ethane, and the reaction temperature is about 200° C. lower. When the feedstock is switched from mainly propane to mainly isobutane, the reaction heat required for the dehydrogenation of isobutane is about 6% lower than that required for the dehydrogenation of propane, but the reaction temperature is about 60° C. lower. Thus, when the dehydrogenation feedstock is switched (e.g., from ethane to isobutane, or from propane to isobutane), significant adjustments are required to allow for the adaptation of the required reaction temperature and reaction heat.

[0017] The heat of reaction required per unit time can be expressed as a function of the catalyst circulation rate and the ΔT between regeneration and reaction, as provided in Equation (1):

[0018]

number

[0019] One way to make fine adjustments to meet the reaction temperature and heat requirements is to vary the catalyst circulation rate from the regenerator to the reactor. However, if the catalyst circulation rate is the only parameter to be adjusted, it is difficult to obtain the correct reactor temperature (T) while also maintaining an adequate heat of reaction. Reactor ) (Equation (1)). For example, when switching from propane to isobutane as the dehydrogenation feedstock, the molar flow rate of the hydrocarbons must be kept the same and T Regen If the temperature is kept constant at 750°C, the T Reactor is 630℃, T Regen -T Reactor However, for isobutane, T Reactor is 570°C, and T Regen -T Reactor is 180° C. Therefore, to meet the heat and temperature requirements when changing the feed from propane to isobutane, the catalyst circulation rate needs to be reduced by about 40%.

[0020] In a fixed design, there is a limit to how much the catalyst circulation rate can be adjusted. This catalyst circulation rate is further limited by the range of catalyst to feed ratios required to provide sufficient catalytic activity for dehydrogenation. In addition, the molar flow rates of the reactants are not an independent parameter due to the requirement of proper fluid dynamics.

[0021] Regenerator temperature (T Regen ) can be adjusted to help meet the reaction temperature and heat of reaction criteria. For example, T Regen can be adjusted by varying the amount of fuel gas injected into the regenerator vessel for combustion, as discussed further below. However, when reducing the amount of fuel gas for combustion, the temperature of the catalyst in the combustion zone is also reduced, and may be reduced to the point where the temperature is too low for complete or near complete combustion of the fuel gas. This can be particularly troublesome when CH4-based fuel gas is used, as the amount of unreacted CH4 in the effluent may be higher than the lower flammable limit, thereby presenting a significant safety risk.

[0022] Thus, when switching dehydrogenation feedstocks, careful consideration is required of many parameters, including reaction heat requirements, catalyst circulation rate, reactant feed flow rate, reaction temperature, and regeneration temperature. The methods and catalysts described herein provide the ability to carry out fuel gas combustion over a wide range of temperatures, thereby reducing T Regen As a result, the methods and compositions disclosed herein allow for control of the reaction temperature, heat of reaction, and the ability to meet the requirements for the amount of catalyst needed for the dehydrogenation of different feedstocks.

[0023] The catalytic system and method for producing dehydrogenated hydrocarbons of the present disclosure will now be described with respect to an exemplary FCDh system. It should be understood that the schematic diagram of the figure is merely an exemplary system, and other FCDh systems are contemplated as well, and the concepts described may be utilized in such alternative systems. For example, the concepts described may be equally applicable to other systems with alternative reactor and regeneration units, such as those operating under non-flow conditions, or those that are downers rather than risers. In addition, other dehydrogenation systems (e.g., utilizing different chemical feedstocks) are contemplated, and therefore the catalytic system and method for producing dehydrogenated hydrocarbons described herein should not be limited to only embodiments for reactor systems designed to produce light olefins through an FCDh process, such as the reactor system described with respect to the figure. In describing the simplified schematic diagram of the figure, numerous valves, temperature sensors, electronic controls, etc. that may be used and are well known to those skilled in the art are not included. Furthermore, accompanying components that are often included within such reactor systems, such as air supplies, heat exchangers, surge tanks, etc. are also not included. However, it should be understood that these components are within the scope of the present disclosure.

[0024] Referring now to the Figures, an exemplary reactor system 102 is depicted in schematic form. The reactor system 102 generally includes a reactor section 200 and a catalyst processing section 300. As used with respect to the Figures, the reactor section 200 refers to the portion of the reactor system 102 where the primary process reactions occur. For example, the reactor system 102 may be an FCDh system in which a hydrocarbon-containing feedstock is dehydrogenated in the presence of a dehydrogenation catalyst in the reactor section 200 of the reactor system 102. The reactor section 200 generally includes a reactor 202, which may include a downstream reactor section 250, an upstream reactor section 230, and a catalyst separation section 210 that serves to separate the catalyst from the effluent generated in the reactor 202.

[0025] Similarly, when used with respect to the figures, catalyst processing section 300 refers to a portion of reactor system 102 where catalyst is treated in some manner, such as removing coke deposits, heating, reactivating, or a combination thereof. Catalyst processing section 300 generally includes a combustor 350, a riser 330, a catalyst separation section 310, and an oxygen processing zone 370. Combustor 350 may be in fluid communication with riser 330. Combustor 350 may also be in fluid communication with catalyst separation section 210 via a water column 426, which may deliver deactivated catalyst from reactor section 200 to catalyst processing section 300 for catalyst processing (e.g., decoking, heating, reactivation, etc.). The oxygen treatment zone 370 may be in fluid communication with the upstream reactor section 250 (e.g., via a water column 424 and a transfer riser 430), which may deliver the treated catalyst from the catalyst treatment portion 300 back to the reactor portion 200. The combustor 350 may include one or more lower combustor inlet ports 352 connecting the air flow inlet 428 to the combustor 350. The air flow inlet 428 may deliver air and / or other reactive gases, such as oxygen-containing gases, to the combustor 350. The combustor 350 may also include a fuel flow inlet 354 through which a fuel, such as a hydrocarbon stream, may be delivered to the combustor 350. The oxygen treatment zone 370 may include an oxygen-containing gas flow inlet 372 through which an oxygen-containing gas may be delivered to the oxygen treatment zone 370 for oxygen treatment of the catalyst.

[0026] Still referring to the figure, the general operation of reactor system 102 to carry out a dehydrogenation reaction under normal operating conditions will now be described. During operation of reactor section 200 of reactor system 102, a hydrocarbon-containing feedstock may enter reactor section 200 via feedstock inlet 434 and contact a fluidized catalyst introduced into reactor section 200 via transfer riser 430, and a dehydrogenated hydrocarbon effluent may exit reactor section 200 via pipe 420. In one or more embodiments, the hydrocarbon-containing feedstock and fluidized catalyst are introduced into upstream reactor section 250, the hydrocarbon-containing feedstock contacts the catalyst in upstream reactor section 250, and the resulting mixture flows upwardly to and through downstream reactor section 230 to produce an olefin-containing effluent.

[0027] In one or more embodiments, the hydrocarbon-containing feedstock comprises ethane, propane, n-butane, i-butane, ethylbenzene, or combinations thereof. In some embodiments, the hydrocarbon-containing feedstock comprises at least 50 weight percent (wt%), at least 60 wt%, at least 70 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt% ethane. In some embodiments, the hydrocarbon-containing feedstock comprises 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 at least 99 wt% propane. In some embodiments, the hydrocarbon-containing feedstock comprises 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 at least 99 wt% n-butane. In some embodiments, the hydrocarbon-containing feedstock comprises 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 at least 99% by weight of i-butane. In some embodiments, the hydrocarbon-containing feedstock comprises 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 at least 99% by weight of ethylbenzene. In some embodiments, the hydrocarbon-containing feedstock comprises 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 at least 99% by weight of the sum of ethane, propane, n-butane, i-butane, and ethylbenzene.

[0028] The temperature at which the reactor portion 200 of the reactor system 102 operates may depend on the species of hydrocarbon being dehydrogenated. For example, in an embodiment, the hydrocarbon undergoing dehydrogenation may include ethane, and the temperature at which the dehydrogenation is carried out may be between 700° C. and 850° C., e.g., 710° C. and 850° C., 720° C. and 850° C., 730° C. and 850° C., 740° C. and 850° C., 750° C. and 850° C., 760° C. and 850° C., 770° C. and 850° C., 780° C. and 850° C., 790° C. and 850° C., 800° C. and 850° C., 810° C. and 850° C., 820° C. The temperature may be from 800°C to 850°C, 830°C to 850°C, 840°C to 850°C, 700°C to 840°C, 700°C to 830°C, 700°C to 820°C, 700°C to 810°C, 700°C to 800°C, 700°C to 790°C, 700°C to 780°C, 700°C to 770°C, 700°C to 760°C, 700°C to 750°C, 700°C to 740°C, 700°C to 730°C, 700°C to 720°C, or 700°C to 710°C.

[0029] In an embodiment, the hydrocarbon undergoing dehydrogenation may include propane, and the temperature at which the dehydrogenation is carried out may be between 550° C. and 700° C., e.g., between 560° C. and 700° C., between 570° C. and 700° C., between 580° C. and 700° C., between 590° C. and 700° C., between 600° C. and 700° C., between 610° C. and 700° C., between 620° C. and 700° C., between 630° C. and 700° C., between 640° C. and 700° C., between 650° C. and 700° C., between 660° C. and 700° C., between 670° C. and 700° C. The temperature may be 700°C, 680°C to 700°C, 690°C to 700°C, 550°C to 690°C, 550°C to 680°C, 550°C to 670°C, 550°C to 660°C, 550°C to 650°C, 550°C to 640°C, 550°C to 630°C, 550°C to 620°C, 550°C to 610°C, 550°C to 600°C, 550°C to 590°C, 550°C to 580°C, 550°C to 570°C, or 550°C to 560°C.

[0030] In an embodiment, the hydrocarbon undergoing dehydrogenation may include isobutane, and the temperature at which the dehydrogenation is carried out may be between 500° C. and 650° C., e.g., between 510° C. and 650° C., between 520° C. and 650° C., between 530° C. and 650° C., between 540° C. and 650° C., between 550° C. and 650° C., between 560° C. and 650° C., between 570° C. and 650° C., between 580° C. and 650° C., between 590° C. and 650° C., between 600° C. and 650° C., between 610° C. and 650° C., between 620° C. and 650° C. The temperature may be 650°C, 630°C to 650°C, 640°C to 650°C, 500°C to 640°C, 500°C to 630°C, 500°C to 620°C, 500°C to 610°C, 500°C to 600°C, 500°C to 590°C, 500°C to 580°C, 500°C to 570°C, 500°C to 560°C, 500°C to 550°C, 500°C to 540°C, 500°C to 530°C, 500°C to 520°C, or 500°C to 510°C.

[0031] In one or more embodiments, the dehydrogenated hydrocarbon effluent comprises light olefins. As used in this disclosure, the term "light olefins" refers to one or more of ethylene, propylene, and butene. The term butene includes any isomer of butene, such as α-butylene, cis-β-butylene, trans-β-butylene, and isobutylene. In some embodiments, the dehydrogenated hydrocarbon effluent comprises at least 25% by weight of light olefins based on the total weight of the dehydrogenated hydrocarbon effluent. For example, the dehydrogenated hydrocarbon effluent may comprise at least 35% by weight of light olefins, at least 45% by weight of light olefins, at least 55% by weight of light olefins, at least 65% by weight of light olefins, or at least 75% by weight of light olefins based on the total weight of the dehydrogenated hydrocarbon effluent.

[0032] In one or more embodiments, the catalyst includes an active metal component, a promoter component including platinum and at least one other precious metal, and a support. In embodiments, the active metal component includes gallium. In embodiments, the active metal component consists of gallium.

[0033] In one or more embodiments, the catalyst comprises 0.1 wt% to 10 wt% of the active metal component based on the total weight of the catalyst. For example, the catalyst may comprise 0.1 wt% to 7.5 wt%, 0.1 wt% to 5 wt%, 0.1 wt% to 2.5 wt%, 0.1 wt% to 0.5 wt%, 0.5 wt% to 10.0 wt%, 0.5 wt% to 7.5 wt%, 0.5 wt% to 5 wt%, 0.5 wt% to 2.5 wt%, 2.5 wt% to 10.0 wt%, 2.5 wt% to 7.5 wt%, 2.5 wt% to 5 wt%, 5 wt% to 10 wt%, 5 wt% to 7.5 wt%, or 7.5 wt% to 10 wt% of the active metal component based on the total weight of the catalyst. Without being bound by any particular theory, it is believed that catalysts containing less than 0.1 wt% of the active metal component may not provide sufficient or commercially viable dehydrogenation activity. Furthermore, it is believed that catalysts containing more than 10 wt. % active metal may not provide enough additional dehydrogenation activity to justify the increased cost of including the greater amount of active metal.

[0034] In one or more embodiments, the catalyst comprises a promoter component comprising 5 ppmw to 500 ppmw of platinum based on the total weight of the catalyst. For example, the catalyst may comprise 5 ppmw to 450 ppmw, 5 ppmw to 400 ppmw, 5 ppmw to 350 ppmw, 5 ppmw to 300 ppmw, 5 ppmw to 250 ppmw, 5 ppmw to 200 ppmw, 5 ppmw to 150 ppmw, 5 ppmw to 100 ppmw, 5 ppmw to 50 ppmw, ... The platinum content may be from 100 ppmw to 500 ppmw, 100 ppmw to 500 ppmw, 150 ppmw to 500 ppmw, 200 ppmw to 500 ppmw, 250 ppmw to 500 ppmw, 300 ppmw to 500 ppmw, 350 ppmw to 500 ppmw, 400 ppmw to 500 ppmw, or 450 ppmw to 500 ppmw of platinum.

[0035] In one or more embodiments, the catalyst comprises a weight ratio of active metal to platinum of from 5 to 600. For example, the weight ratio of active metal to platinum can be from 5 to 550, 5 to 500, 5 to 450, 5 to 400, 5 to 350, 5 to 300, 5 to 250, 5 to 200, 5 to 150, 5 to 100, 5 to 50, 5 to 10, 10 to 600, 50 to 600, 100 to 600, 150 to 600, 200 to 600, 50 to 600, 300 to 600, 350 to 600, 400 to 600, 450 to 600, 500 to 600, 550 to 600, or even 590 to 600. Without intending to be bound by any particular theory, it is believed that catalysts containing an active metal to platinum weight ratio of less than 5 may not provide the desired dehydrogenation activity. Further, it is believed that catalysts containing an active metal to platinum weight ratio of greater than 600 may not be sufficiently reactivated and / or may not exhibit the desired selectivity.

[0036] The promoter component of the catalyst further comprises a second precious metal. The second precious metal may be ruthenium, rhodium, palladium, rhenium, iridium, or a combination of two or more thereof. In an embodiment, the second precious metal is palladium. Without intending to be bound by any particular theory, it is believed that the presence of this second precious metal may improve the catalyst's ability to combust the combustion fuel, as described below, so that lower temperatures may be used during the catalytic treatment step after the dehydrogenation step. In this way, lower temperatures may be used to treat the deactivated catalyst after the dehydrogenation step relative to the temperatures required when the promoter component contains platinum but does not contain the second precious metal.

[0037] In one or more embodiments, the catalyst comprises a weight ratio of the second precious metal to platinum that is between 0.05 and 1.5. For example, the weight ratio of the second precious metal to platinum can be between 0.05 and 1.4, 0.05 and 1.3, 0.05 and 1.2, 0.05 and 1.1, 0.05 and 1, 0.05 and 0.9, 0.05 and 0.8, 0.05 and 0.7, 0.05 and 0.6, 0.05 and 0.5, 0.05 and 0.4, 0.05 and 0.3, 0. 0.5 to 0.2, 0.05 to 0.1, 0.1 to 1.5, 0.2 to 1.5, 0.3 to 1.5, 0.4 to 1.5, 0.5 to 1.5, 0.6 to 1.5, 0.7 to 1.5, 0.8 to 1.5, 0.9 to 1.5, 1 to 1.5, 1.1 to 1.5, 1.2 to 1.5, 1.3 to 1.5, or 1.4 to 1.5.

[0038] In one or more embodiments, the catalyst optionally includes a second promoter selected from the group consisting of an alkali metal, an alkaline earth metal, and a combination of an alkali metal and an alkaline earth metal. In one or more embodiments, the catalyst composition, if present, may include less than 5 wt.% of the second promoter based on the total weight of the catalyst. For example, the catalyst may include greater than 0 wt.% to 5 wt.%, greater than 0 wt.% to 4 wt.%, greater than 0 wt.% to 3 wt.%, greater than 0 wt.% to 2 wt.%, greater than 0 wt.% to 1 wt.%, 1 wt.% to 5 wt.%, 1 wt.% to 4 wt.%, 1 wt.% to 3 wt.%, 1 wt.% to 2 wt.%, 2 wt.% to 5 wt.%, 2 wt.% to 4 wt.%, 2 wt.% to 3 wt.%, 3 wt.% to 5 wt.%, 3 wt.% to 4 wt.%, or 4 wt.% to 5 wt.% of the second promoter based on the total weight of the catalyst.

[0039] In one or more embodiments, the catalyst comprises a support material. Specifically, the catalyst may comprise an active metal component, a first promoter component, and optionally a second promoter disposed and / or dispersed on the support material. In some embodiments, the support material comprises one or more of alumina, silica-containing alumina, titanium-containing alumina, lanthanide-containing alumina, zirconium-containing alumina, magnesia-containing alumina, and combinations of two or more thereof.

[0040] Still referring to the figure, the dehydrogenated hydrocarbon effluent and catalyst may exit downstream reactor section 230 and be sent to separation device 220 in catalyst separation section 210. The catalyst may be separated from the dehydrogenated hydrocarbon effluent in separation device 220. The dehydrogenated hydrocarbon effluent may then be transferred from catalyst separation section 210. For example, the separated dehydrogenated hydrocarbon effluent may be removed from reactor system 102 at gas outlet port 216 of catalyst separation section 210 via pipe 420. In one or more embodiments, separation device 220 may be a powder separation system that may include two or more stages of powder separation.

[0041] Still referring to the figure, following separation from the dehydrogenated hydrocarbon effluent in separation device 220, the catalyst may generally travel through stripper 224 to reactor catalyst outlet port 222 where it may be transferred out of reactor section 200 via stream tower 426 to combustor 350 of catalyst processing section 300. Optionally, the catalyst may also be transferred directly back to upstream reactor section 250 via stream tower 422. In one or more embodiments, the recycled catalyst from stripper 224 may be premixed with the treated catalyst from catalyst processing section 300 in transfer riser 430.

[0042] Once delivered to catalyst treatment section 300, the catalyst may be treated in catalyst treatment section 300. As used in this disclosure, the term "catalyst treatment" refers to preparing the catalyst for reintroduction into the reactor section of the reactor system. In one or more embodiments, treating the catalyst includes removing coke deposits from the catalyst, increasing the temperature of the catalyst through combustion of a combustion fuel, reactivating the catalyst, stripping one or more components from the catalyst, or a combination thereof.

[0043] In some embodiments, treating the catalyst includes at least one fuel gas and coke on the deactivated catalyst in the presence of oxygen in the combustor 350 to remove coke deposits on the catalyst and / or heat the catalyst to produce treated catalyst and combustion gas. As used in this disclosure, the term "treated catalyst" refers to the catalyst treated in the catalyst treatment section 300 of the reactor system 102. The treated catalyst can be separated from the combustion gas in the catalyst separation section 310 and, in some embodiments, can then be reactivated by oxygen treatment of the heated catalyst. Oxygen treatment can include contacting the catalyst with an oxygen-containing gas for a period of time sufficient to reactivate the catalyst.

[0044] In one or more embodiments, the combustion fuel includes coke or other contaminants that have accumulated on the catalyst in the reactor section 200. The catalyst may be coked following reactions in the reactor section 200, and the coke may be removed from the catalyst by a combustion reaction in the combustor 350. For example, an oxidant (such as air) may be provided to the combustor 350 via the air inlet 428. Alternatively or additionally, a supplemental fuel may be injected into the combustor 350 and burned to heat the catalyst, such as when coke does not form on the catalyst or when the amount of coke formed on the catalyst is not sufficient to burn to heat the catalyst to a desired temperature. Suitable supplemental fuels may include methane, natural gas, ethane, propane, hydrogen, or any gas that provides energy value when burned. In one or more embodiments, the catalyst may be only slightly coked, and in these embodiments, the supplemental fuel is the primary fuel used to heat the catalyst.

[0045] The treated catalyst may exit the combustor 350 and pass through the riser 330 to the end-of-rise separator 378, where gas and solid components from the riser 330 may be at least partially separated. The steam and remaining solids may be transferred to a secondary separation device 320 in the catalyst separation section 310, where the remaining treated catalyst is separated from gases from the catalyst treatment (e.g., coke deposits and gases released by the combustion of the auxiliary fuel). In some embodiments, the secondary separation device 320 may include one or more cyclone separation units, which may be arranged in series or in multiple cyclone pairs. Combustion gases from the combustion of the coke and / or auxiliary fuel during the treatment of the catalyst, or other gases introduced to the catalyst during the catalyst treatment, may be removed from the catalyst treatment section 300 via a combustion gas outlet 432.

[0046] As previously discussed, treating the catalyst in the catalyst-treatment portion 300 of the reactor system 102 may include reactivating the catalyst. Combusting an auxiliary fuel in the presence of the catalyst to heat the catalyst may further deactivate the catalyst. Thus, in some embodiments, the catalyst may be reactivated by conditioning the catalyst through oxygen treatment. The oxygen treatment to reactivate the catalyst may occur after the combustion of the auxiliary fuel to heat the catalyst. In some embodiments, the oxygen treatment includes treating the treated catalyst with an oxygen-containing gas. The oxygen-containing gas may include an oxygen content of 5 mole percent (mol.%) to 100 mol.%, based on the total molar flow rate of the oxygen-containing gas. In some embodiments, the oxygen treatment includes exposing the catalyst to a flow of oxygen-containing gas for a period of time sufficient to reactivate the treated catalyst (e.g., increase the catalytic activity of the treated catalyst) while maintaining the treated catalyst at a temperature of at least 660°C.

[0047] In one or more embodiments, treatment of the treated catalyst with an oxygen-containing gas occurs in an oxygen treatment zone 370. In some embodiments, the oxygen treatment zone 370 is downstream of the catalyst separation section 310 of the catalyst-treatment section 300 such that the treated catalyst is separated from the combustion gas before being exposed to the oxygen-containing gas during oxygen treatment. In some embodiments, the oxygen treatment zone 370 includes a fluid-solid contacting device. The fluid-solid contacting device may include a baffle or grid structure to facilitate contact of the treated catalyst with the oxygen-containing gas. Fluid-solid contacting devices are described in more detail in U.S. Pat. Nos. 9,827,543 and 9,815,040, the contents of both of which are incorporated herein by reference.

[0048] In one or more embodiments, treating the catalyst in the catalyst treatment section 300 of the reactor system 102 includes stripping the treated catalyst of molecular oxygen trapped within or between the catalyst particles and physisorbed oxygen that is desorbable at a temperature of at least 660° C. The stripping step may include maintaining the treated catalyst at a temperature of at least 660° C. and exposing the treated catalyst to a stripping gas that is substantially free of molecular oxygen and combustible fuel for a period of time sufficient to remove the molecular oxygen from between the particles and the physisorbed oxygen that is desorbable at a temperature of at least 660° C. Further description of these catalyst reactivation processes is disclosed in U.S. Pat. No. 9,834,496, the entirety of which is incorporated herein by reference.

[0049] Still referring to the figure, following treatment of the catalyst, the treated catalyst may be sent from the catalyst treatment section 300 back to the reactor section 200 via the stream tower 424. For example, the treated catalyst may be sent from the oxygen treatment zone 370 via the stream tower 424 and the transfer riser 430 upstream to the reactor section 250 where the treated catalyst may be further utilized in the dehydrogenation reaction of the hydrocarbon-containing feedstock. Thus, during operation, the catalyst may be circulated between the reactor section 200 and the catalyst treatment section 300. In general, the treated chemical streams including the hydrocarbon-containing feedstock and the dehydrogenated hydrocarbon effluent may be gaseous and the catalyst may be a fluidized particulate solid. In one or more embodiments, the reactor system 102 may include a hydrogen inlet stream 480 that provides supplemental hydrogen to the reactor system 102.

[0050] As previously discussed, the combustion reaction in the combustor 350 (i.e., the combustion of the combustion fuel) may be facilitated by a catalyst. That is, the catalyst may provide the combustion activity within the combustor 350. However, the combustion activity of the catalyst may decrease over time as the catalyst is cycled between the reactor section 200 and the catalytic processing section 300. As a result, during operation of the reactor system 102, the combustion fuel may no longer combust at the typical operating temperature and pressure of the combustor 350 without sufficient maintenance of the combustion activity in the combustor 350. A typical operating temperature of the combustor 305 may be between 600° C. and 850° C., and a typical operating pressure of the combustor 350 may be between 15 pounds per square inch absolute (psia) and 60 psia.

[0051] In an embodiment, the operating temperature of the combustor 305 may be 50° C. to 200° C. higher than the temperature at which the dehydrogenation is performed. For example, the combustion temperature may be 60° C. to 200° C. higher than the temperature at which the dehydrogenation is performed, e.g., 70° C. to 200° C., 80° C. to 200° C., 90° C. to 200° C., 100° C. to 200° C., 110° C. to 200° C., 120° C. to 200° C., 130° C. to 200° C., 140° C. to 200° C., 150° C. to 200° C., 160° C. to 200° C., 170° C. to 200° C., 180° C. 200°C, 190°C to 200°C, 50°C to 190°C, 50°C to 180°C, 50°C to 170°C, 50°C to 160°C, 50°C to 150°C, 50°C to 140°C, 50°C to 130°C, 50°C to 120°C, 50°C to 110°C, 50°C to 100°C, 50°C to 90°C, 50°C to 80°C, 50°C to 70°C, or 50°C to 60°C higher. As described above, the presence of the second precious metal in the promoter component is believed to reduce the temperature required to combust the catalyst after the dehydrogenation stage. As a result, the two components of the reactor system, the reactor section and the catalyst processing section 300, can be operated more efficiently, giving the operator a higher level of control over the thermodynamics of the process.

[0052] According to one embodiment, either alone or in combination with any other embodiment, a method for dehydrogenation of one or more hydrocarbons and regeneration and reactivation of a catalyst composition includes contacting a first gaseous stream containing a first hydrocarbon with a catalyst composition at a first temperature in a dehydrogenation reactor, thereby producing a first dehydrogenated hydrocarbon and a deactivated catalyst composition, combusting at least one fuel gas and coke over the deactivated catalyst at a second temperature in the presence of oxygen, thereby producing a heated catalyst composition, and reactivating the catalyst in the presence of oxygen. The second temperature is 50°C to 200°C higher than the first temperature. The catalyst composition includes an active metal including gallium, a support, and a promoter including platinum and at least one precious metal selected from the group consisting of ruthenium, rhodium, palladium, rhenium, iridium, and combinations of two or more thereof. The weight ratio of the total amount of the second precious metal to platinum is 0.05 to 1.5.

[0053] According to a second embodiment, either alone or in combination with any other embodiment, the first hydrocarbon is ethane and the first temperature is between 700°C and 850°C.

[0054] According to a third aspect, either alone or in combination with any other aspect, the first hydrocarbon is propane and the first temperature is between 550°C and 700°C.

[0055] According to a fourth aspect, either alone or in combination with any other aspect, the first hydrocarbon is isobutane and the first temperature is between 500°C and 650°C.

[0056] According to a fifth aspect, either alone or in combination with any other aspect, the method further comprises, after reactivation, contacting the second gaseous stream with the catalyst composition, the second gaseous stream comprising a second hydrocarbon different from the first hydrocarbon, thereby producing a second dehydrogenated hydrocarbon and a deactivated catalyst composition.

[0057] According to a sixth embodiment, either alone or in combination with any other embodiment, the dehydrogenation reactor comprises a fluidized bed.

[0058] According to the seventh aspect, either alone or in combination with any other aspect, the fuel gas comprises methane.

[0059] According to an eighth aspect, either alone or in combination with any other aspect, the precious metal is selected from the group consisting of ruthenium, rhodium, palladium, iridium, and combinations of two or more thereof.

[0060] According to a ninth embodiment, either alone or in combination with any other embodiment, the precious metal is palladium.

[0061] According to a tenth aspect, either alone or in combination with any other aspect, a catalyst composition comprises an active metal comprising gallium, a support, and a promoter comprising platinum and at least one precious metal selected from the group consisting of ruthenium, rhodium, palladium, rhenium, iridium, and combinations of two or more thereof, wherein the weight ratio of the total amount of the second precious metal to the platinum is 0.05 to 1.5.

[0062] According to an eleventh aspect, either alone or in combination with any other aspect, the support is selected from the group consisting of alumina, silica-containing alumina, titanium-containing alumina, lanthanide-containing alumina, zirconium-containing alumina, magnesia-containing alumina, and combinations of two or more thereof.

[0063] According to a twelfth aspect, either alone or in combination with any other aspect, the catalyst composition comprises from 0.1% to 10% by weight of the active metal component.

[0064] According to a thirteenth aspect, either alone or in combination with any other aspect, the catalyst composition comprises from 5 parts per million by weight (ppmw) to 500 ppmw of platinum.

[0065] According to a fourteenth embodiment, either alone or in combination with any other embodiment, the catalyst composition further comprises a second promoter selected from the group consisting of alkali metals, alkaline earth metals, and combinations of alkali metals and alkaline earth metals.

[0066] According to a fifteenth aspect, either alone or in combination with any other aspect, the catalyst composition comprises greater than 0 wt.% to 5 wt.% of a second promoter.

[0067] One or more features of the present disclosure will be illustrated in light of the following examples. EXAMPLES

[0068] The following examples are illustrative in nature and should not be construed as serving to limit the scope of the present application.

[0069] Example 1 - Dehydrogenation and Combustion Using Platinum and Palladium-Supported Gallium-Based Catalysts A series of alumina supported catalysts are prepared using the conventional incipient wetness method. The incipient wetness method is performed by first dissolving the metal precursors, i.e. gallium nitrate, potassium nitrate, tetraammine platinum nitrate, and tetraammine palladium nitrate, in water. The resulting solution is contacted with a catalyst support, i.e. alumina, having the same pore volume as the volume of added solution, for a time period ranging from overnight, i.e., 6 hours to 14 hours. The equivalent volume promotes the uptake of the metals by capillary action instead of the diffusion process, which is much slower than the capillary action process. The resulting platinum and palladium supported gallium based catalysts are dried and calcined at 750 °C for 2 hours. All catalysts have the same Ga and K loadings (1.5 wt% and 0.25 wt%, respectively). The respective Pt and Pd loadings are shown in Table 1.

[0070] [Table 1]

[0071] The dehydrogenation performance of these platinum and palladium supported gallium based catalysts is illustrated using propane dehydrogenation as a model reaction, with the aim to determine the range of Pd loading that has no or little effect on the dehydrogenation performance.

[0072] The dehydrogenation performance was evaluated in a fixed-bed laboratory test apparatus under ambient pressure using reaction-regeneration cycles. Each cycle was performed at a temperature of 625° C. and for 8 hours. -1 The dehydrogenation step was performed using a 120-second propane pulse (95% propane / 5% inert gas) at a weight hourly space velocity (WHSV) of 1.0 g / m2 and a T RegenThe cycle includes a regeneration step at 200° C., where the catalyst is first treated with simulated combustion effluent (8% CO, 4.0% O, 16% H2O in inert gas) for 3 minutes, followed by treatment in air for 10 minutes. Samples are collected for approximately 17 seconds at cycle 20.

[0073] The composition of the reaction products was determined by Gas Chromatography (GC). The feed conversion and product selectivity were determined by equations (1) and (2):

number

[0074] The results, summarized in Table 2, show nearly equivalent dehydrogenation performance at low Pd levels (Pd:Pt ratio < 50%, Samples B and C vs. Sample A) and acceptable dehydrogenation performance at higher Pd levels (Pd:Pt ratio < 150%, Samples D and E vs. Sample A). Sample F, with only Pd and no Pt, showed very poor dehydrogenation performance.

[0075] [Table 2]

[0076] A similar trend was observed with increasing Pt loading in the catalyst, as shown in Table 3. In these experiments, the WHSV of propane was increased for 10 h. -1 The protocol described above is used, except that the ion exchange rate is increased to 100%.

[0077] [Table 3]

[0078] Fuel gas combustion test, 0.59 hours -1 The experiment was carried out in a fixed-bed laboratory reactor at ambient pressure with a WHSV of methane of 10 ...

[0079] [Table 4]

[0080] When the temperature is above 720°C, the catalyst without Pd can provide good methane combustion activity. However, when the temperature is below 720°C, the presence of Pd enhances the combustion activity of the catalyst. For example, compare the performance of Sample D with that of Sample A. Thus, the combination of Pd and Pt as promoters for fuel gas combustion allows fuel gas combustion in a wider temperature range.

[0081] Example 2 - Dehydrogenation and Combustion Using Platinum and Iridium Supported Gallium-Based Catalysts The Pt-Ir supported gallium-based catalyst samples are prepared using the same procedure described above for the Pt-Pd supported gallium-based catalysts, except that Ir is supported on catalyst A using iridium nitrate in the second impregnation step. The compositions are provided in Table 5.

[0082] [Table 5]

[0083] The same combustion analysis as discussed above for the Pt-Pd supported gallium based catalyst is carried out using the Pt-Ir supported gallium based catalyst, and the results are provided in Table 6.

[0084] [Table 6]

[0085] Similar to the results with Pt-Pd supported gallium-based catalysts, the catalyst without Ir can provide good methane combustion activity when the temperature is above 720°C. However, when the temperature is below 720°C, the presence of Ir enhances the combustion activity of the catalyst. For example, compare the performance of sample K with that of sample A. Thus, the combination of Ir and Pt as promoters for fuel gas combustion allows fuel gas combustion in a wider temperature range.

[0086] Example 3 - Dehydrogenation and Combustion Using Platinum and Ruthenium Supported Gallium-Based Catalysts The Pt-Ru supported gallium based catalyst samples are prepared using the same procedure described above for the Pt-Pd supported gallium based catalysts, except that Ru is supported on catalyst A using ruthenium chloride in the second impregnation step. The compositions are provided in Table 7.

[0087] [Table 7]

[0088] The same combustion analysis as discussed above for the Pt-Pd supported gallium based catalyst is carried out using the Pt-Ru supported gallium based catalyst, and the results are provided in Table 8.

[0089] [Table 8]

[0090] Similar to the results with Pt-Pd supported gallium-based catalysts, the catalyst without Ru can provide good methane combustion activity when the temperature is above 720°C. However, when the temperature is below 720°C, the presence of Ru enhances the combustion activity of the catalyst. For example, compare the performance of sample L at 650°C with that of sample A. Thus, the combination of Ru and Pt as promoters for fuel gas combustion allows fuel gas combustion in a wider temperature range.

[0091] Example 4 - Dehydrogenation and Combustion Using Platinum and Rhodium Supported Gallium Catalysts The Pt-Rh supported gallium-based catalyst samples are prepared using the same procedure described above for the Pt-Pd supported gallium-based catalysts, except that Rh is supported on catalyst A using rhodium nitrate in the second impregnation step. The compositions are provided in Table 9.

[0092] [Table 9]

[0093] The same combustion analysis as discussed above for the Pt-Pd supported gallium based catalyst is carried out using the Pt-Rh supported gallium based catalyst, and the results are provided in Table 10.

[0094] [Table 10]

[0095] Similar to the results with Pt-Pd supported gallium-based catalysts, the catalyst without Rh can provide good methane combustion activity when the temperature is above 720°C. However, when the temperature is below 720°C, the presence of Rh enhances the combustion activity of the catalyst. For example, compare the performance of sample M at 650°C with that of sample A. Thus, the combination of Rh and Pt as promoters for fuel gas combustion allows fuel gas combustion in a wider temperature range.

[0096] It will be apparent to those skilled in the art that various modifications can be made to the described embodiments without departing from the spirit and scope of the claimed subject matter. Thus, it is intended that the present specification cover modifications and variations of the described embodiments provided such modifications and variations come within the scope of the appended claims and their equivalents.

Claims

1. 1. A process for the dehydrogenation of one or more hydrocarbons and the regeneration and reactivation of a catalyst composition, comprising: contacting a first gaseous stream comprising a first hydrocarbon with a catalyst composition at a first temperature in a dehydrogenation reactor, thereby producing a first dehydrogenated hydrocarbon and a deactivated catalyst composition; combusting at least one fuel gas and coke over the deactivated catalyst in the presence of oxygen at a second temperature, thereby producing a heated catalyst composition; reactivating the catalyst in the presence of oxygen; Including, the second temperature is 50°C to 200°C higher than the first temperature; The catalyst composition comprises: an active metal including gallium; a promoter comprising platinum and at least one precious metal selected from the group consisting of ruthenium, rhodium, palladium, rhenium, iridium, and combinations of two or more thereof, wherein the weight ratio of the total amount of the second precious metal to the platinum is 0.05 to 1.5; Carrier and A method comprising:

2. 2. The method of claim 1, wherein the first hydrocarbon is ethane and the first temperature is between 700°C and 850°C.

3. 2. The method of claim 1, wherein the first hydrocarbon is propane and the first temperature is between 550°C and 700°C.

4. 2. The method of claim 1, wherein the first hydrocarbon is isobutane and the first temperature is between 500°C and 650°C.

5. 5. The method of any one of claims 1 to 4, further comprising, after the reactivation, contacting a second gaseous stream with the catalyst composition, the second gaseous stream comprising a second hydrocarbon different from the first hydrocarbon, thereby producing a second dehydrogenated hydrocarbon and the deactivated catalyst composition.

6. The process of any one of claims 1 to 4, wherein the dehydrogenation reactor comprises a fluidized bed.

7. The method of any one of claims 1 to 4, wherein the fuel gas comprises methane.

8. 5. The method of any one of claims 1 to 4, wherein the noble metal is selected from the group consisting of ruthenium, rhodium, palladium, iridium, and combinations of two or more thereof.

9. The method according to any one of claims 1 to 4, wherein the noble metal is palladium.

10. 1. A catalyst composition comprising: an active metal component comprising gallium; a promoter component comprising platinum and at least one precious metal selected from the group consisting of ruthenium, rhodium, palladium, rhenium, iridium, and combinations of two or more thereof; Carrier and Including, A catalyst composition, wherein the weight ratio of the total amount of the second precious metal to platinum is 0.05 to 1.

5.

11. 11. The catalyst composition of claim 10, wherein the support is selected from the group consisting of alumina, silica-containing alumina, titanium-containing alumina, lanthanide-containing alumina, zirconium-containing alumina, magnesia-containing alumina, and combinations of two or more thereof.

12. 11. The catalyst composition of claim 10, wherein the catalyst composition comprises 0.1 wt. % to 10 wt. % of the active metal component.

13. Catalyst composition according to any one of claims 10 to 12, wherein the catalyst composition comprises from 5 parts per million by weight (ppmw) to 500 ppmw of platinum.

14. 13. The catalyst composition of any one of claims 10 to 12, wherein the catalyst composition further comprises a second promoter selected from the group consisting of alkali metals, alkaline earth metals, and combinations of the alkali metals and the alkaline earth metals.

15. 15. The catalyst composition of claim 14, wherein the catalyst composition comprises greater than 0 to 5 wt. % of a second promoter.

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