Methods for making olefinic materials that include utilizing water and passivation agents

Abstract

An olefinic material may be made by a method that may include passing a hydrocarbon-containing feed, a passivation agent, steam, and a particulate solid into a reactor of an olefinic material production system. In the reactor a portion of the hydrocarbon-containing feed may be reacted to form the olefinic material. The molar ratio of hydrocarbon-containing feed to passivation agent may be at least 2,000:1. The molar ratio of hydrocarbon-containing feed passed into the reactor to water passed into the reactor may be at least 10:1. The passivation agent may consist of one or more of a sulfur-containing compound, a nitrogen-containing compound, a hydroxide moiety-containing compound excluding water, or a phosphorous containing compound. The method may further include passing the particulate solid from the reactor to a combustor of the olefinic material production system and heating the particulate solid in the combustor by one or both of combusting a supplemental fuel in the combustor or combusting coke present on the particulate solid in the combustor. The method may further include passing the particulate solid from the combustor to the reactor, such that all or a portion of the particulate solid is continuously cycled between the reactor and the combustor.

Description

METHODS FOR MAKING OLEFINIC MATERIALS THAT INCLUDE UTILIZING WATER AND PASSIVATION AGENTSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 665,052 filed June 27, 2024, the contents of which are incorporated in their entirety herein.TECHNICAL FIELD

[0002] Embodiments of the present disclosure generally relate to chemical processing and, particular, to methods and system for making olefinic materials.BACKGROUND

[0003] Olefinic materials, such as ethylene, butene, propylene, and styrene, may be used as base materials to produce many different materials, such as polyethylene, polypropylene, isopropanol, and acrylic acid, which may be used in, e.g., packaging, construction, and textiles. As a result of this utility, there is a worldwide demand for olefinic materials. However, methods for efficiently producing such olefinic materials are challenging, and improvements in technology for such purposes are desired by industry.SUMMARY

[0004] Described herein, according to one or more embodiments, are methods for making olefinic materials that comprise reacting hydrogen-containing feeds to form olefinic materials that utilize a particulate solid, such as a catalyst, that is circulated between a reactor and a combustor. The reaction may take place at relatively high temperatures (e.g., at least 500 °C), which may cause coking in the reactor and / or other portions of the system. Coking may be mitigated, as described in one or more embodiments herein, by passing water and a passivation agent into the reactor, where the amount of water utilized is relatively low. It is believed, according to some embodiments, that the water, even in small amounts, such as amounts that would not significantly promote passivation on its own, may mitigate the absorption of the passivation agent onto the particulate solid in the reactor, thus allowing more passivation agent to be utilized for passivation to prevent coking and / or lessening deactivation of the particulate solid.

[0005] According to one or more embodiments, olefinic material may be made by a method that may comprise passing a hydrocarbon-containing feed, a passivation agent, steam, and a particulate solid into a reactor of an olefinic material production system. In the reactor a portion of the hydrocarbon-containing feed may be reacted to form the olefinic material. The molar ratio of hydrocarbon-containing feed to passivation agent may be at least 2,000:1. The molar ratio of hydrocarbon-containing feed passed into the reactor to water passed into the reactor may be at least 10:1. The passivation agent may consist of one or more of a sulfur-containing compound, a nitrogen-containing compound, a hydroxide moiety-containing compound excluding water, or a phosphorous containing compound. The method may further comprise passing the particulate solid from the reactor to a combustor of the olefinic material production system and heating the particulate solid in the combustor by one or both of combusting a supplemental fuel in the combustor or combusting coke present on the particulate solid in the combustor. The method may further comprise passing the particulate solid from the combustor to the reactor, such that all or a portion of the particulate solid is continuously cycled between the reactor and the combustor.

[0006] 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 drawing and claims, or recognized by practicing the described embodiments. The drawing is included to provide a further understanding of the embodiments and, together with the detailed description, serves to explain the principles and operations of the claimed subject matter. However, the embodiment depicted in the drawing is illustrative and exemplary in nature, and not intended to limit the claimed subject matter.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The following detailed description may be better understood when read in conjunction with the following drawing, in which:

[0008] FIG. 1 schematically depicts a olefinic material production system, according to one or more embodiments of the present disclosure;

[0009] FIG. 2 schematically depicts a combustor of an olefinic material production system, according to one or more embodiments of the present disclosure; and

[0010] FIG. 3 schematically depicts a portion of a particulate solids separation section, according to one or more embodiments of the present disclosure.

[0011] When describing the simplified schematic illustration of FIGS. 1-3, the numerous 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.

[0012] Reference will now be made in greater detail to various embodiments, some of which are illustrated in the accompanying drawing.DETAILED DESCRIPTION

[0013] According to embodiments described herein, olefinic materials may be produced in olefinic material production systems that operate by circulating particulate solids (e.g., catalysts) between reactors and combustors. The olefinic material production systems generally operate at elevated temperatures (e.g., at least 500 °C). Generally, metal surfaces that may be present in the olefin material production systems may catalyze coking of hydrocarbons at such temperatures. Excessive coking can be a problem, as the olefinic material production system may need to more frequently shut down for cleaning, and system efficiencies in general may be decreased.

[0014] According to one or more embodiments, coking caused by metal surfaces, and in particular, carbon steel, stainless steel, or other steel alloys, can be mitigated by use of a passivation agent. As described herein, passivation agents may form a passive layer on the metal surface that reduces coke formation. However, it has been discovered that passivation agents may be absorbed onto the solid particulate (e.g., a catalyst or oxygen carrier material), which may reduce activity of the particulate solid for its intended purpose. Additionally, absorption of the passivation agent by the particulate solid reduces the amount of passivation agent available to form the passivation layer.

[0015] According to one or more embodiments described herein, it has been discovered that utilizing a relatively small amount of water passed into the reactor may be beneficial in promoting particulate solid activity in the reactor by lessening the propensity for the passivation agent to absorb onto the particulate solid. As such, passivation agent may be passed into the reactor, where it can form a passivation layer over metal surfaces in the reactor. For example, in a catalytic dehydrogenation reaction scheme, a passivation agent and relatively small amounts of water can be co-fed with an alkane reactant into the reactor, where the relatively small amount of water reduces the passivation agent absorption onto the catalyst. In such embodiments, it has been discovered that reduction in absorbed passivation agent can improve dehydrogenation activity, promoting process efficiency and improving overall yield while at the same time mitigating coking in the reactor.

[0016] Moreover, it should be understood that, unlike some conventional embodiments, the amount of water passed into the reactor is relatively small, such that the molar ratio of hydrocarbon-containing feed passed into the reactor to water passed into the reactor is at least 10:1 (such as at least 20:1, at least 30:1, at least 40: 1, at least 50:1, at least 60:1, at least 70:1, at least 80:1, at least 90:1, or even at least 100:1). Without being bound by theory, it is believed that this relatively small amount of water as compared to hydrocarbon-containing feed is effective to reduce passivation agent absorption onto the particulate solid. However, it is small enough that it does not meaningfully contribute to forming a passivation layer. For example, in some conventional embodiments, water may be passed into the reactor in greater amounts with a goal of passivating metal surfaces. However, in the embodiments presently disclosed, the water is unexpectedly utilized in smaller amounts than such conventional embodiments and in combination with a non- water passivation agent.

[0017] Without being bound by theory, it is believed that the water may be absorbed onto the particulate solid, thereby limiting the amount of sites for absorption of passivation agent. However, the water may not, in general, be as detrimental to particulate solid activity as compared with the passivation agent.

[0018] According to additional embodiments, water may be passed into various other portions of an olefinic material production system than the reactor, and / or water can be producedin the olefinic material production system by combustion to further remove passivation agents that may be absorbed onto the particulate solid.

[0019] As described herein, water refers to H2O in any phase, including steam. In embodiments described herein the water may be injected as steam, or may become steam from liquid water upon entering the high temperatures experienced in the reactor or other portions of the olefinic material production system. It is contemplated that various types of water may be utilized, such as water that includes some other compounds, such as in trace amounts.

[0020] As described herein, a “passivation agent” refers to any one or more chemical compounds that can form a passivation layer over a surface, which reduces propensity for coking. Without being bound by any particular theory, in general, passivation refers to coating a material so that it becomes "passive", that is, less readily affected by the environment, as is understood by those skilled in the art. Passivation involves creation of an outer layer of shield material that is applied as a microcoating, created by chemical reaction with the base material, or allowed to build by spontaneous oxidation by exposure to an oxygen-containing environment. A wide variety of passivation agents are contemplated for use as described herein, where the material upon which the passivation layer is to be formed is important in selecting the passivation agent. As described herein, a passivation agent may include a mixture of multiple chemical compounds, or may include only a single chemical compound.

[0021] According to one or more embodiments, the passivation agent may comprise, consist essentially of, or consist of one or more sulfur-containing compounds (i.e., any chemical compound that includes at least one sulfur atom). In additional embodiments, the passivation agent may comprise, consist essentially of, or consist of one or more phosphorus-containing compounds (i.e., any chemical compound that includes at least one phosphorus atom). In additional embodiments, the passivation agent may comprise, consist essentially of, or consist of one or more hydroxide moiety-containing compounds excluding water (i.e., any chemical compound that includes at least one hydroxide moiety, exclusive of water). According to additional embodiments, the passivation agent may comprise, consist essentially of, or consist of one or more nitrogencontaining compounds (i.e., any chemical compound that includes at least one nitrogen atom). In additional embodiments, the passivation agent may comprise, consist essentially of, or consist of mixtures of any combination of sulfur-containing compounds, phosphorus-containingcompounds, hydroxide moiety-containing compounds excluding water, and nitrogen-containing compounds.

[0022] According to embodiments, without limitation, sulfur-containing compounds may be chosen from compounds that include H2S or those that can decompose to H2S. For example, contemplated sulfur-containing compounds include methyl mercaptan, dimethylsulfide (DMS), dimethyl disulfide (DMDS), dipropyldisulphides, dibutyldisulphides, ditertbutyldisulphide (DTBDS), diphenyldisulphide (DPDS), carbon disulphide, benzothiophenes, bibenzyl sulphide, phosphorothioate, methanedithione, methyldisulfanyl, methaylsulfanyl, and dimethyl sulfoxides. Without limitation, phosphorus-containing compounds may be chosen from triphenyl phosphite or triethyl phosphite (TEP), triphenyl phosphine (TPP), tri-o-tolylphosphine (TTP), and triphenyl phosphine oxide (TPPO), benzyl diethyl phosphite (BDP), and phosphine. Without limitation, hydroxide moiety-containing compounds may be chosen from ethanol, butanol, glycerol, ethylene glycol, 1,2 propanediol, 1,3 propanediol. 1,2 cyclopentanediol, and 1,2 cyclohexanediol Additionally, without limitation, nitrogen-containing compounds may be chosen from ammonia, methayl amine, ethyl amine, butyl amine, dimethyl amine, diethyl amine, dibutyl amine, trimethyl amine, triethyl amine, tributyl amine, piperidine, N-methylpiperidine, and N-phenylpiperidine.

[0023] Methods for making olefinic materials may utilize olefinic material production systems, and such methods are described in the context of such olefinic material production systems. As described herein, an olefinic material production system is any system that can produce olefinic materials. As described herein, olefinic materials refer to compounds that include at least one alkene moiety (i.e., a C=C double bond). In some embodiments, the olefinic materials may be “light olefins” such as ethylene, propylene, butene, or styrene. These olefinic materials can be produced via dehydrogenation from ethane, propane, butane, and ethylbenzene, respectively, which may be included as the feed into the reactor.

[0024] According to embodiments described herein, particulate solids may be utilized in the process to form olefinic materials, whereby the particulate solids continuously circulate between a reactor and a combustor during normal steady-state operation during olefinic material production. The olefinic materials are produced in the reactor, and the particulate solids are heated in the combustor by combustion of a supplemental fuel, burning of coke, or both. Various reaction mechanisms, and associated reactants, may be utilized to form the olefinic materials. For example,dehydrogenation may be utilized to convert paraffins to olefins, such as ethane to ethylene, butane to butylene, and propane to propylene, or to convert ethylbenzene to styrene. Such dehydrogenation reactions may utilize a catalyst, which may be the solid particulate. In additional embodiments, olefinic materials may be produced by cracking reactions, dehydration reactions, and methanol-to-olefin reactions. These reaction types may utilize different hydrocarbon feed streams and different catalytic particulate solids to produce the olefinic materials from hydrocarbon feeds. In additional embodiments, it is contemplated that the particulate solids may be non-catalytic solids such as, for example, materials capable of carrying oxygen (referred to sometimes herein as “oxygen carrier materials”). For example, such oxygen carrier materials may be utilized along with catalyst whereby hydrogen produced in a dehydrogenation reactor is combusted by contact with oxygen supplied from the oxygen carrier materials. In additional embodiments, oxygen carrier materials may be utilized without catalyst, where thermal dehydrogenation may from hydrogen that is combusted by contact with the oxygen from the oxygen carrier materials.

[0025] According to some embodiments, the chemical processing may comprise a dehydrogenation reaction that utilizes circulating a catalyst between the chemical processing vessel 100 and a regeneration unit, where alkanes are converted to alkenes in the chemical processing vessel 100 and where the catalyst is heated by a supplemental fuel in the regeneration unit. Such a process may convert propane to propylene, such as is described in U.S. Pat. No. 10,227,271, the entirety of which is incorporated by reference in this disclosure.

[0026] In additional embodiments, chemical processing may comprise a dehydrogenation reaction that utilizes circulating a solid particulate oxygen carrier material between the chemical processing vessel 100 and a regeneration unit, where alkanes are converted to alkenes in the chemical processing vessel 100 by thermal dehydrogenation, and where the produced hydrogen gas is converted to water by contact with oxygen released from the oxygen carrier material. Such a process may convert ethane to ethylene, such as is described in WO 2024 / 059554 Al, the entirety of which is incorporated by reference in this disclosure.

[0027] In additional embodiments, chemical processing may comprise a dehydrogenation reaction that utilizes circulating both a catalyst and a solid particulate oxygen carrier material between the chemical processing vessel 100 and a regeneration unit, where alkanes are convertedto alkenes in the chemical processing vessel 100 by catalytic dehydrogenation, and where the produced hydrogen gas is converted to water by contact with oxygen released from the oxygen carrier material. Such a process may convert ethane to ethylene, such as is described in U.S. Patent No. 11,724,974, the entirety of which is incorporated by reference in this disclosure.

[0028] Embodiments of the methods presently disclosed are described in detail herein in the context of the olefinic material production system 100 of FIG. 1 operating as a fluidized dehydrogenation reactor system to produce olefinic materials, such as propylene. 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. For example, the concepts described herein may be equally applied to other systems with alternate reactor units and regeneration units, such as those that operate under non-fluidized conditions or include downers rather than risers. It should be further understood that not all portions of FIG. 1 should be construed as essential to the claimed subject matter. Moreover, while the recited method steps in the appended claims are described herein in the context of FIG. 1, such recited method steps should be understood as adaptable to other systems, as would be understood by those skilled in the art.

[0029] Referring now to FIG. 1, an example olefinic material production system 100 that may be suitable for use with the methods and / or apparatuses described herein is schematically depicted. The olefinic material production system 100 generally comprises multiple system components that are included in a reactor portion 200 and a catalyst processing portion 300. As described herein, “system components” refer to portions of the olefinic material production system 100, such as reactors, separators, transfer lines, combinations thereof, and the like. As used herein in the context of FIG. 1, the reactor portion 200 generally refers to the portion of the olefinic material production system 100 in which the major process reaction takes place (e.g., dehydrogenation) to form an olefinic material-containing effluent. A hydrocarbon-containing feed enters the reactor portion 200, is contacted with a catalyst, converted to an olefinic materialcontaining effluent (containing product and unreacted feed), and exits the reactor portion 200. The reactor portion 200 comprises a reactor 202 which may include an upstream reactor section 250 and a downstream reactor section 230. According to one or more embodiments, as depicted in FIG. 1, the reactor portion 200 may additionally include a catalyst separation section 210, which serves to separate the catalyst from the olefinic material-containing effluent formed in the reactor 202. Also, as used herein, the catalyst processing portion 300 generally refers to the portion of theolefinic material production system 100 where the catalyst is in some way processed, such as by combustion, to, e.g., improve catalytic activity by decoking and / or heating the catalyst. The catalyst processing portion 300 may comprise a combustor 350 and a riser 330, and may additionally comprise a catalyst separation section 310. In one or more embodiments, the catalyst separation section 210 may be in fluid communication with the combustor 350 (e.g., via standpipe 426) and the catalyst separation section 310 may be in fluid communication with the upstream reactor section 250 (e.g., via standpipe 424 and transport riser 430).

[0030] Generally as is described herein, in embodiments illustrated in FIG. 1, catalyst is circulated between the reactor portion 200 and the catalyst processing portion 300. It should be understood that when “catalysts” are referred to herein, they may refer to solid materials that are catalytically active for a desired reaction. The terms “catalytic activity” and “catalyst activity” refer to the degree to which the catalyst is able to catalyze the reactions conducted in the olefinic material production system 100. The catalyst that exits the reactor portion 200 may be deactivated catalyst. As used herein, “deactivated” may refer to a catalyst which has reduced catalytic activity or is cooler as compared to catalyst entering the reactor portion 200. However, deactivated catalyst may maintain some catalytic activity. Reduced catalytic activity may result from contamination with a substance such as coke. Coke may form on the catalyst within the reactor portion 200. Reactivation (sometimes called “regeneration” herein) may remove the contaminant such as coke, raise the temperature of the catalyst, or both. In embodiments, deactivated catalyst may be reactivated by catalyst reactivation in the catalyst processing portion 300. The deactivated catalyst may be reactivated by, but not limited to, removing coke by combustion, oxidizing the catalyst, other reactivation process, or combinations thereof. In some embodiments, the catalyst may be heated during reactivation by combustion of a supplemental fuel, such as hydrogen, methane, ethane, propane, natural gas, or combinations thereof. The reactivated catalyst from the catalyst processing portion 300 is then passed back to the reactor portion 200. The catalyst is heated during regeneration to aid with regeneration and also because heated catalyst serves as a heat carrier to carry heat from the combustor 350 to the reactor portion 200 to facilitate the dehydrogenation reaction.

[0031] In non-limiting examples, the olefinic material production system 100 described herein may be utilized to produce light olefins from a hydrocarbon-containing feed. According to one or more embodiments, the reaction may be a dehydrogenation reaction. According to suchembodiments, the hydrocarbon-containing feed may comprise one or more of ethane, propane, butane, and ethylbenzene. In one or more embodiments, the hydrocarbon-containing feed 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 one or more embodiments, the hydrocarbon- containing feed 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 hydrocarbon-containing feed 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 hydrocarbon-containing feed 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 n-butane, i-butane, or combinations thereof.

[0032] In one or more embodiments, the catalyst may comprise, consist essentially of, or consist of one or more of gallium, indium, or thallium; one or more of platinum, palladium, rhodium, iridium, ruthenium, or osmium; and a support. As described herein, “consisting essentially of’ refers to materials with less than 1 wt.% of the non-recited materials (i.e., consisting essentially of A and B means A and B combined are at least 99 wt.% of the composition). In additional embodiments, the catalyst may comprise, consist essentially of, or consist of one or more of gallium, indium, or thallium; one or more of platinum, palladium, rhodium, iridium, ruthenium, or osmium; a support; and one or both of alkali or alkaline earth metals. As is described herein, the catalyst may be solid particles suitable for fluidization.

[0033] Still referring to FIG. 1, the hydrocarbon-containing feed may enter feed inlet 434 into the reactor 202, and the olefinic material-containing effluent may exit the olefinic material production system 100 via pipe 420. According to one or more embodiments, the olefinic material production system 100 may be operated by feeding a hydrocarbon-containing feed (e.g., in a feed stream) and a fluidized catalyst into the upstream reactor section 250. The hydrocarbon-containing feed contacts the catalyst in the upstream reactor section 250, and each flow upwardly into and through the downstream reactor section 230 to produce an olefin-containing effluent. The reactor 202 may operate at relatively high temperatures, such as from 500 °C to 800 °C (e.g., from 500 °C to 550 °C, 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, or any combination of one or more of these ranges).

[0034] Now referring to FIG. 1 in detail, the reactor portion 200 may comprise an upstream reactor section 250, a transition section 258, and a downstream reactor section 230, such as a riser. The transition section 258 may connect the upstream reactor section 250 with the downstream reactor section 230. As depicted in FIG. 1, the upstream reactor section 250 may be positioned below the downstream reactor section 230. Such a configuration may be referred to as an upflow configuration in the reactor 202. The upstream reactor section 250 may include a vessel, drum, barrel, vat, or other container suitable for a given chemical reaction. As depicted in FIG. 1, the upstream reactor section 250 may be connected to the downstream reactor section 230 via the transition section 258. The upstream reactor section 250 may generally comprise a greater cross- sectional area than the downstream reactor section 230. The transition section 258 may be tapered from the size of the cross-section of the upstream reactor section 250 to the size of the crosssection of the downstream reactor section 230 such that the transition section 258 projects inwardly from the upstream reactor section 250 to the downstream reactor section 230. For example, the transition section 258 may be a frustum.

[0035] The upstream reactor section 250 may be connected to a transport riser 430, which, in operation may provide reactivated catalyst in a feed stream to the reactor portion 200. The reactivated catalyst and / or reactant chemicals may be mixed with a distributor 260 housed in the upstream reactor section 250. The catalyst entering the upstream reactor section 250 via transport riser 430 may be passed through standpipe 424 to a transport riser 430, thus arriving from the catalyst processing portion 300. In some embodiments, catalyst may come directly from the catalyst separation section 210 via standpipe 422 and into a transport riser 430, where it enters the upstream reactor section 250, where in such embodiments some of the catalyst is not passed through the catalyst processing portion 300. The catalyst can also be fed via standpipe 422 directly to the upstream reactor section 250 (not depicted in FIG. 1). This catalyst may be somewhat deactivated, but may still, in some embodiments, be suitable for reaction in the upstream reactor section 250, particularly when used in combination with reactivated catalyst.

[0036] In one or more embodiments, the catalyst may have a residence time within the reactor portion 200 of less than or equal to 5 minutes. As the term is used herein, “residence time” refers to the average amount of time the catalyst or other specified material spends within the reactor portion 200 in contact with the feed (e.g., time from first contact with feed to time of separation from product). As it is an average, the amount of time the catalyst may spend withinthe reactor portion 200 during any given cycle may not be equal to the average, but over time will average out to be equal to about the residence time. In some embodiments, the catalyst may have a residence time within the reactor portion 200 of less than or equal to 4.5 min., less than or equal to 4 min., less than or equal to 3.5 min., less than or equal to 3 min., less than or equal to 2.5 min., less than or equal to 2 min., less than or equal to 1.5 min., less than or equal to 1 min., less than or equal to 0.5, or less than or equal to 0.1 min. Without being bound by theory, it is believed that catalyst residence time greater than 3 minutes may increase equipment costs without a matching increase in catalyst dehydrogenation performance. However, it is believed that catalyst residence time less than 0.1 minutes may not allow the catalyst to sufficiently catalyze the dehydrogenation reaction.

[0037] Still referring to FIG. 1, in one or more embodiments, based on the shape, size, and other processing conditions (such as temperature and pressure) in the upstream reactor section 250 and the downstream reactor section 230, the upstream reactor section 250 may operate as a fluidized bed, such as in a fast fluidized, turbulent, or bubbling bed upflow reactor, while the downstream reactor section 230 may operate in more of a plug flow manner, such as in a riser reactor. For example, the reactor 202 of FIG. 1 may comprise an upstream reactor section 250 operating as a fast fluidized, turbulent, or bubbling bed reactor and a downstream reactor section 230 operating as a dilute phase riser reactor, with the result that the average catalyst and gas flow moves concurrently upward. As the term is used herein, “average flow” refers to the net flow, i.e., the total upward flow minus the retrograde or reverse flow, as is typical of the behavior of fluidized particles in general. As described herein, a “fast fluidized” reactor may refer to a reactor utilizing a fluidization regime wherein the superficial velocity of the gas phase is greater than the choking velocity and may be semi-dense in operation. As described herein, a “turbulent” reactor may refer to a fluidization regime where the superficial velocity of less than the choking velocity and is more dense than the fast fluidized regime. As described herein, a “bubbling bed” reactor may refer to a fluidization regime wherein well defined bubbles in a highly dense bed are present in two distinct phases. The “choking velocity” refers to the minimum velocity required to maintain solids in the dilute-phase mode in a vertical conveying line. As described herein, a “dilute phase riser” may refer to a riser reactor operating at above choking velocity.

[0038] According to one or more embodiments, in addition to the hydrocarbon-containing feed, the passivation agent and water are passed into the reactor 202. According to some embodiments, the passivation agent and water may be co-fed with the hydrocarbon containing feed through the transport riser 430 and into the upstream reactor section 250 in the same stream. However, in other embodiments, it is contemplated that the water may be fed in a different stream than the hydrocarbon-containing feed and / or the passivation agent, and / or the passivation agent may be fed in a different stream than the hydrocarbon-containing feed and / or the water. For example, the water and / or the passivation agent may be passed into the upstream reactor section 250 through a port or ports on the sidewall of the upstream reactor section 250.

[0039] The passivation agent may be passed into the reactor 202 in amounts whereby the molar ratio of hydrocarbon-containing feed to passivation agent is at least 2,000:1 (such as at least 4,000:1, at least 6,000:1, at least 8,000:1, or even at least 10,000:1). Such amounts may be sufficient to form a passivation layer on metal surfaces in the reactor 202, but not so large as to substantially deactivate the catalyst (or other particulate solid) even in spite of the absorption reduction offered by the water present on the particulate solid.

[0040] It should be understood that, without being bound by any theory, it is believed that the injection of the water into the reactor 202 (and particularly into the upstream reactor section 250) is important since that is the region of the system 100 where the olefinic material is being produced and, thereby, where solids activity is most important. In embodiments, the presence of water in the system 100 in other regions than the reactor 202 is contemplated, but these may be more supplemental in nature as compared with the water entering the reactor 202.

[0041] According to embodiments, the olefinic material-containing effluent and the catalyst may be passed out of the downstream reactor section 230 to a separation device 220 in the catalyst separation section 210, where the catalyst is at least partially separated from the olefin- containing effluent, which is transported out of the catalyst separation section 210. According to one or more embodiments, following separation from vapors in the separation device 220, the catalyst may generally move through the stripper 224 to the catalyst outlet port 222 where the catalyst is transferred out of the reactor portion 200 via standpipe 426 and into the catalyst processing portion 300.

[0042] According to one or more embodiments, the separation device 220 may be a cyclonic separation system, which may include two or more stages of cyclonic separation. In embodiments where the separation device 220 comprises more than one cyclonic separation stages, the first separation device into which the fluidized stream enters is referred to a primary cyclonic separation device. The fluidized effluent from the primary cyclonic separation device may enter into a secondary cyclonic separation device for further separation. Primary cyclonic separation devices may include, for example, primary cyclones, and systems commercially available under the names VSS (commercially available from UOP), LD2 (commercially available from Stone and Webster), and RS2 (commercially available from Stone and Webster). Primary cyclones are described, for example, in U.S. Patent Nos. 4,579,716; 5,190,650; and 5,275,641, which are each incorporated by reference in their entirety herein. In some separation systems utilizing primary cyclones as the primary cyclonic separation device, one or more set of additional cyclones, e.g. secondary cyclones and tertiary cyclones, are employed for further separation of the catalyst from the product gas. It should be understood that any primary cyclonic separation device may be used in embodiments of the present disclosure.

[0043] Now referring to FIG. 3, an embodiment of a catalyst separation section 210 suitable for use in the olefinic material production system 100 of FIG. 1 is schematically depicted. In the embodiment of FIG. 3, two cyclonic separation devices are utilized in series. As depicted, the catalyst separation section 210 may include a primary separation device 520. The primary separation device 520 is contained within a shell 530 and has a body 521, an inlet 522 from the downstream reactor section 230 (i.e., a riser in FIGS. 1 and 3), an outlet 524 and a solids discharge dipleg 526. A fluidized solid stream enters the primary separation device 520 through inlet 522. In the primary separation device 520, a major part of entrained solids, e.g. catalyst particles, are separated from the fluidized solid stream. The separated solids exit the primary separation device through discharge dipleg 526 leaving a primary separation device effluent which comprises solids not removed by the primary separation device 520 and fluid, e.g. gaseous product. The primary separation device effluent passes vertically upward and out of the primary separation device 520 through outlet 524 and into the secondary separation device 540 through primary separation device outlet tube 542 and then through crossover duct 570. The secondary separation device 540 further comprises a body 541, an outlet 544 and a solids discharge dipleg 546. The secondary separation device 540 further separates out solids from the primary separationdevice effluent. Solids separated out in the secondary separation device 540 exit downward through dipleg 546. The products may be passed through the outlet 544 and out of the catalyst separation section 210 via the pipe 420, passing through a plenum.

[0044] As depicted in FIG. 3, quench stream 296 may enter the upper portion of the primary separation device outlet tube 542, which is positioned directly above the primary separation device 520. It is believed that such an arrangement may be desirable for proper mixing of the quench stream with the effluent of the primary separation device 540 and to reduce residence time between the exit of the primary separation device 540 and the mixing with the quench stream 296.

[0045] Still referring to FIG. 1 , the separated catalyst is passed from the catalyst separation section 210 to the combustor 350. In some embodiments, the catalyst may be exposed to another oxy gen-containing gas, such as air, downstream of the reactor 202 and upstream of the combustor 350, such as in a standpipe leading to the combustor 350. Such oxygen exposure may serve to oxidize the catalyst prior to combustion, which may improve combustion catalytic functionality.

[0046] In the combustor 350, the catalyst may be processed by, for example, combustion of coke with oxygen (if coke is present) and with combustion of supplemental fuel. For example, and without limitation, the catalyst may be de-coked and / or supplemental fuel may be combusted to heat the catalyst. The catalyst is then passed out of the combustor 350 and through the riser 330 to a riser termination separator 378, where the gas and solid components from the riser 330 are at least partially separated. The vapor and remaining solids are transported to a secondary separation device 320 in the catalyst separation section 310 where the remaining catalyst is separated from the gases from the catalyst processing (e.g., gases emitted by combustion of spent catalyst or supplemental fuel, referred to herein as flue gas). The flue gas may pass out of the catalyst processing portion 300 via outlet pipe 432. The separated catalyst is then passed through the oxygen treatment zone 370 within the catalyst separation section 310 to the upstream reactor section 250 via standpipe 424 and transport riser 430, where it is further utilized in a catalytic reaction. Thus, the catalyst, in operation, may cycle between the reactor portion 200 and the catalyst processing portion 300. In general, the processed chemical streams, including the hydrocarbon-containing feed and olefinic material-containing effluent may be gaseous, and the catalyst may be fluidized particulate solid.

[0047] Referring now to the catalyst processing portion 300, as depicted in FIG. 1, the combustor 350 of the catalyst processing portion 300 may include one or more lower reactor portion inlet ports 352 and may be in fluid communication with the riser 330. Oxygen-containing gas, such as air, may be passed through pipe 428 into the combustor 350. In general, the oxygencontaining gas may comprise at least 10 mol.% oxygen. The combustor 350 may be in fluid communication with the catalyst separation section 210 via standpipe 426, which may supply spent catalyst from the reactor portion 200 to the catalyst processing portion 300 for regeneration. The combustor 350 and riser 330, collectively referred to as the catalyst combustion reactor 302, may operate with similar or identical fluidization regimes as to what was disclosed with respect to the upstream reactor section 250 and downstream reactor section 230 of the reactor portion 200. That is, the combustor 350 may operate as a fluidized bed, such as in a fast fluidized, turbulent, or bubbling bed upflow reactor, while the riser 330 may operate in more of a plug flow manner, such as in a riser reactor. Geometries as described with respect to the upstream reactor section 250 and downstream reactor section 230 may equally apply to the combustor 350 and riser 330. Additionally, the combustor 350 may also include a fuel inlet 354, which may supply a fuel, such as a hydrocarbon stream, to the combustor 350.

[0048] Still referring to olefinic material operation mode in steady state, as described herein, the catalyst may be heated in the catalyst processing portion 300 by combustion of supplemental fuels. Supplemental fuels may combust with oxygen to heat the catalyst, and supplemental fuels such as a supplemental fuel, such as hydrogen, methane, ethane, propane, natural gas, or combinations thereof.

[0049] Now referring to FIG. 2, one embodiment of a combustor 350 suitable with the system and methods of FIG. 1 is schematically depicted. As shown in FIG. 1, the combustor 350 may comprise a vessel 360 whereby catalyst may enter the vessel 360 through downcomer 362. Alternatively or additionally, in embodiments, the catalyst may enter the vessel 102 from a side inlet (not shown) or from a bottom feed (not shown), passing upward through the air distributor 364. The catalyst may impinge upon and may be distributed by a splash guard. The combustor 350 may include the air distributor 364, which may be a plate distributor and may be located at or slightly below the height of the splash guard. Above the air distributor 364 and the outlet of the downcomer 362 may one or more grids 366. The girds may operate as bubble breakers to promote even fluidization within the combustor 350.

[0050] Still referring to FIG. 2, the combustor 350 may also include a plurality of gas distributors 368 through which the supplemental fuel is fed into the combustor 350, which may be in fluid communication with the fuel inlet 354. Additionally, liquid fuel used for system startup may be fed through inlet 380.

[0051] Turning back to FIG. 1, as described in one or more embodiments, following separation of flue gas from catalyst in the riser termination separator 378 and secondary separation device 320, treatment of the processed catalyst with an oxygen-containing gas, such as air, is conducted in the oxygen treatment zone 370. In general, the oxy gen-containing gas in the oxygen treatment zone 370 may comprise at least 10 mol.% oxygen, and is substantially void of combustable gaseous hydrocarbons that are present in the combustor 350. In some embodiments, the oxygen treatment zone 370 includes a fluid solids contacting device. The fluid solids contacting device may include baffles or grid structures to facilitate contact of the processed catalyst with the oxy gen-containing gas. Examples of fluid solid contacting devices are described in further detail in U.S. Patent Nos. 9,827,543 and 9,815,040. The fluidization regime within the oxygen treatment zone may be bubbling bed type fluidization. The oxygen treatment zone 370 may include an oxygen-containing gas inlet 372, which may supply an oxygen-containing gas to the oxygen treatment zone 370 for oxygen treatment of the catalyst.

[0052] As is disclosed herein, in one or more embodiments the catalyst may be exposed to an oxy gen-containing gas in oxygen treatment zone 370. For example, the catalyst may be exposed to an oxygen-containing gas for from 2 min. to 20 min., such as from 2 min. to 4 min., from 4 min. to 6 min., from 6 min. to 8 min., from 8 min. to 10 min., from 10 min. to 12 min., from 12 min. to 14 min., from 14 min. to 16 min., from 16 min. to 18 min., from 18 min. to 20 min., or any combination of these ranges. In some embodiments the catalyst may be exposed to an oxygen containing gas from 4 min. to 18 min., from 6 min. to 17 min., from 8 min. to 16 min., or from 10 min. to 15 min. Without being bound by theory, it is believed that exposure of the catalyst to an oxygen-containing gas for more than 20 minutes may increase equipment costs without a matching increase in catalyst regeneration efficiency. However, it is believed that oxygen-containing gas exposure for less than 2 minutes may lead to less efficient regeneration of the catalyst which may reduce the catalyst’s dehydrogenation activity. In one or more embodiments, the catalyst may be exposed to the oxygen-containing gas at a temperature of at least 650 °C, such as from 650 °C to 800 °C.

[0053] In one or more embodiments, the olefinic material may be present in a “product stream” sometimes called an “olefin product-containing effluent” and include light olefins. Such a stream exits the olefinic material production system 100 of FIG. 1 and may be subsequently processed.

[0054] According to one or more embodiments, water may be passed into regions of the system 100 other than the reactor 202, as disclosed herein. For example, and without limitation, water may be passed into solids transport line passing the particulate solid from the combustor 350 to the reactor 202 upstream of the reactor 202 (e.g., the standpipe 424 in the embodiment of FIG. 1). In additional embodiments, water can be passed into the oxygen treatment zone 370 of system 100. For example, the water can be passed directly into a sidewall of the oxygen treatment zone 370 or co-fed with the oxygen-containing stream, such as air.

[0055] According to additional embodiments, water may be passed into the combustor 350. In various embodiments, water may be passed into the combustor 350 along with the supplemental fuel, such as through gas distributor 368, or may be passed into the combustor 350 with the oxy gen-containing gas, such as air through pipe 428. In additional embodiments, the water may be directly injected through a sidewall of the combustor vessel 360. In additional embodiments, the particulate solid, such as dehydrogenation catalyst, may be contacted with water in the standpipe 426.

[0056] According to additional embodiments, water may be passed into the stripper 224 co mixed with the strip fluid fed into the stripper 224. Alternatively, the water may be fed into a sidewall of the stripper 224.

[0057] Numerous technical aspects are presently disclosed, some of which are specifically described hereinbelow as Aspects 1-15.

[0058] Aspect 1. A method for making olefinic material, the method comprising: passing a hydrocarbon-containing feed, a passivation agent, steam, and a particulate solid into a reactor of an olefinic material production system, wherein: in the reactor a portion of the hydrocarbon- containing feed is reacted to form the olefinic material; the molar ratio of hydrocarbon-containing feed to passivation agent is at least 2,000: 1 ; the molar ratio of hydrocarbon-containing feed passed into the reactor to water passed into the reactor is at least 10:1; and the passivation agent consistsof one or more of a sulfur-containing compound, a nitrogen-containing compound, a hydroxide moiety-containing compound excluding water, or a phosphorous containing compound; passing the particulate solid from the reactor to a combustor of the olefinic material production system and heating the particulate solid in the combustor by one or both of combusting a supplemental fuel in the combustor or combusting coke present on the particulate solid in the combustor; and passing the particulate solid from the combustor to the reactor, such that all or a portion of the particulate solid is continuously cycled between the reactor and the combustor.

[0059] Aspect 2. The method of aspect 1, wherein the passivation agent comprises the sulfur-containing compound.

[0060] Aspect 3. The method of aspect 2, wherein the sulfur-containing compound is chosen from hydrogen sulfide, methyl mercaptan, dimethylsulfide (DMS), dimethyl disulfide (DMDS), dipropyldisulphides, dibutyldisulphides, ditertbutyldisulphide (DTBDS), diphenyldisulphide (DPDS), carbon disulphide, benzothiophenes, bibenzyl sulphide, phosphorothioate, methanedithione, methyldisulfanyl, methaylsulfanyl, and dimethyl sulfoxides.

[0061] Aspect 4. The method of any previous aspect, wherein the passivation agent forms a passivation layer over a metal surface of the olefinic material production system that is exposed to hydrocarbons.

[0062] Aspect 5. The method of aspect 5, wherein the passivation layer mitigates coke formation.

[0063] Aspect 6. The method of aspect 5, wherein the metal surface comprises carbon steel, stainless steel, or other steel alloys.

[0064] Aspect 7. The method of any previous aspect, wherein the reactor operates at a temperatures of at least 500 °C.

[0065] Aspect 8. The method of aspect 1, wherein the particulate solid comprises a dehydrogenation catalyst.

[0066] Aspect 9. The method of aspect 1, wherein the particulate solid comprises an oxygen carrier material

[0067] Aspect 10. The method of any previous aspect, wherein the water, the passivation agent, and the hydrocarbon-containing feed is co-fed into the reactor in the same stream.

[0068] Aspect 11. The method of any previous aspect, wherein water is further passed to additional portions of the olefinic material production system besides the reactor.

[0069] Aspect 12. The method of aspect 11, wherein water is further passed into a solids transport line of the olefinic material production system positioned upstream of the reactor and downstream of the combustor, relative to the motion of the particulate solid.

[0070] Aspect 13. The method of aspect 11 , wherein water is further passed into an oxygen treatment zone of the olefinic material production system positioned downstream of the combustor and upstream of the reactor, relative to the motion of the particulate solid.

[0071] Aspect 14. The method of aspect 11, wherein water is further passed into the combustor.

[0072] Aspect 15. The method of aspect 11, wherein water is further passed into a stripper of the olefinic material production system positioned downstream of the reactor and upstream of the combustor, relative to the motion of the particulate solid.Examples

[0073] The following examples are illustrative of some embodiments of the present disclosure, and should not be construed as limiting or essential to any aspect of the appended claimed subject matter.

[0074] Example 1

[0075] A propane dehydrogenation catalyst was tested in a pilot-scale fluidized bed reactor with the reactor and regenerator operating at 620-630 °C and 720-730 °C, respectively. Circulation rate of the catalyst and propane feed rate were adjusted to operate the reactor under these conditions, where the catalyst / propane ratio was 16-45 g / g with corresponding WHSV of 6- 16 hr'1. The propane feed included 30 ppmv methyl mercaptan (a sulfur-containing compound) along with 0.5 vol.% water (with respect to the feed). Pure H2 was used as fuel in the combustor in one subset of these experiments. A control sample was also tested, where no water was used.

[0076] Product and flue gas streams exiting the reactor and combustor, respectively, were analyzed every few minutes via separate gas chromatography and the operating conditions were held constant for at least 4 hours of steady state operation. For catalyst samples that were not exposed to water (the control sample), the amount of sulfur determined to be present on the catalyst was about equal to that which would be expected when all sulfur is absorbed by the catalyst, based on a stoichiometric calculation. However when water was added, as described above, the amount of sulfur present on the catalyst was notably less than what would be stochiometrically expected. For example, at about 2,750 min on stream, the catalyst exposed to steam had a sulfur content of only about 48 ppmw, whereas the expected amount was about 60 ppmw. Thus sulfur deposition was unexpectedly about 20% less than what was expected, which was presumably kept in gas phase and available for formation of a passivation layer.

[0077] For the purposes of describing and defining the present disclosure it is noted that the term “about” are utilized in this disclosure to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. The term “about” are also utilized in this disclosure to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. Additionally, the term “consisting essentially of’ is used in this disclosure to refer to quantitative values that do not materially affect the basic and novel characteristic(s) of the disclosure. For example, a chemical stream “consisting essentially” of a particular chemical constituent or group of chemical constituents should be understood to mean that the stream includes at least about 99.5% of a that particular chemical constituent or group of chemical constituents.

[0078] It is noted that one or more of the following claims utilize the term “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.”

[0079] 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. It should be appreciatedthat 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.

[0080] Having described the subject matter of the present disclosure in detail and by reference to specific embodiments, 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. Rather, the claims appended hereto should be taken as the sole representation of the breadth of the present disclosure and the corresponding scope of the various embodiments described in this disclosure. Further, it will be apparent that modifications and variations are possible without departing from the scope of the appended claims.

Claims

CLAIMS1. A method for making olefinic material, the method comprising: passing a hydrocarbon-containing feed, a passivation agent, steam, and a particulate solid into a reactor of an olefinic material production system, wherein: in the reactor a portion of the hydrocarbon-containing feed is reacted to form the olefinic material; the molar ratio of hydrocarbon-containing feed to passivation agent is at least 2,000:1; the molar ratio of hydrocarbon-containing feed passed into the reactor to water passed into the reactor is at least 10:1; and the passivation agent consists of one or more of a sulfur-containing compound, a nitrogen-containing compound, a hydroxide moiety-containing compound excluding water, or a phosphorous containing compound; passing the particulate solid from the reactor to a combustor of the olefinic material production system and heating the particulate solid in the combustor by one or both of combusting a supplemental fuel in the combustor or combusting coke present on the particulate solid in the combustor; and passing the particulate solid from the combustor to the reactor, such that all or a portion of the particulate solid is continuously cycled between the reactor and the combustor.

2. The method of claim 1, wherein the passivation agent comprises the sulfur-containing compound.

3. The method of claim 2, wherein the sulfur-containing compound is chosen from hydrogen sulfide, methyl mercaptan, dimethylsulfide (DMS), dimethyl disulfide (DMDS), dipropyldisulphides, dibutyldisulphides, ditertbutyldisulphide (DTBDS), diphenyldisulphide (DPDS), carbon disulphide, benzothiophenes, bibenzyl sulphide, phosphorothioate, methanedithione, methyldisulfanyl, methaylsulfanyl, and dimethyl sulfoxides.

4. The method of any previous claim, wherein the passivation agent forms a passivation layer over a metal surface of the olefinic material production system that is exposed to hydrocarbons.

5. The method of claim 5, wherein the passivation layer mitigates coke formation.

6. The method of claim 5, wherein the metal surface comprises carbon steel, stainless steel, or other steel alloys.

7. The method of any previous claim, wherein the reactor operates at a temperatures of at least 500 °C.

8. The method of claim 1, wherein the particulate solid comprises a dehydrogenation catalyst.

9. The method of claim 1, wherein the particulate solid comprises an oxygen carrier material.

10. The method of any previous claim, wherein the water, the passivation agent, and the hydrocarbon-containing feed is co-fed into the reactor in the same stream.

11. The method of any previous claim, wherein water is further passed to additional portions of the olefinic material production system besides the reactor.

12. The method of claim 11, wherein water is further passed into a solids transport line of the olefinic material production system positioned upstream of the reactor and downstream of the combustor, relative to the motion of the particulate solid.

13. The method of claim 11, wherein water is further passed into an oxygen treatment zone of the olefinic material production system positioned downstream of the combustor and upstream of the reactor, relative to the motion of the particulate solid.

14. The method of claim 11, wherein water is further passed into the combustor.

15. The method of claim 11, wherein water is further passed into a stripper of the olefinic material production system positioned downstream of the reactor and upstream of the combustor, relative to the motion of the particulate solid.

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