Methods for producing catalysts that include platinum

Abstract

A catalyst may be made by a method comprising attriting initial support particles, wherein at least a portion of the initial support particles have a size of greater than 10 microns. The attriting of the initial support particles may form at least attrited support particles and fines having a size of less than 10 microns. The method further comprises separating at least a portion of the fines from the attrited support particles, impregnating at least a portion of the attrited support particles with at least platinum to form impregnated support particles, and exposing the impregnated support particles to a temperature of from 400°C to 1000 °C to form the catalyst.

Description

METHODS FOR MAKING CATALYSTS THAT INCLUDE PLATINUMCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 555,657 filed February 20, 2024, the contents of which are incorporated in their entirety herein.TECHNICAL FIELD

[0002] Embodiments described herein generally relate to chemical processing and, more specifically, to catalysts utilized in chemical processing.BACKGROUND

[0003] Catalysts are utilized in a wide variety of chemical conversion processes, such as the production of light olefins, such as ethylene, butene, and propylene. These compounds may be used as base materials to produce many different materials, such as polypropylene, isopropanol, and acrylic acid, which may be used in, e.g., packaging, construction, and textiles. While there are catalyst compositions that are relatively successful in such processes, they may suffer from degradation over time, which may reduce product yields and / or require the catalyst to be replacement with fresh catalyst. As such, there is a need for new catalysts for use in chemical processing systems.SUMMARY

[0004] Catalysts that include platinum on a support may be utilized in a variety of chemical conversion processes, such as fluidized dehydrogenation to form light olefins from alkanes. Some of these processes utilize catalyst in fluidized beds at relatively hot temperatures (e.g., greater than 600 °C) followed by attrition inside of solids / fluids separation devices such as cyclones. It has been observed that platinum, in particular, may be gradually lost from the catalyst in greater amounts than other components of the catalyst while in operation in such reaction systems, reducing catalytic activity and negatively affecting product yields. It has been discovered that platinum loss can be mitigated by preparing the catalyst by a particular process whereby the support material, prior to impregnation with the platinum, is attrited. It is believed that such catalysts have different particle shapes than conventional catalyst that have not been attrited prior to impregnation, and may demonstrate reduced platinum loss when utilized in a fluidized bedconversion process at relatively high temperatures followed by separation from fluids in a cyclonic separation device.

[0005] According to one or more embodiments, a catalyst may be made by a method comprising attriting initial support particles, wherein at least a portion of the initial support particles have a size of greater than 10 microns. The attriting of the initial support particles may form at least attrited support particles and fines having a size of less than 10 microns. The method may further comprise separating at least a portion of the fines from the attrited support particles, impregnating at least a portion of the attrited support particles with at least platinum to form impregnated support particles, and exposing the impregnated support particles to a temperature of from 400 °C to 1000 °C to form the catalyst.

[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 reactor system, according to one or more embodiments of the present disclosure;

[0009] FIG. 2 graphically depicts example data of volume % as a function of particle size of attrited support materials, according to one or more embodiments of the present disclosure; and

[0010] FIG. 3 also graphically depicts example data of volume % as a function of particle size of attrited support materials, according to one or more embodiments of the present disclosure.

[0011] When describing the simplified schematic illustration of FIG. 1, 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] The present disclosure is directed to methods for making catalyst that include at least platinum on a support material. According to one or more embodiments, the methods may include at least attriting initial support particles to from attrited support particles, and then impregnating the attrited support particles. The catalyst that is produced may, according to one or more embodiments, have better retention of platinum when utilized in a reactor system that utilizes a cyclonic separation device, as is described herein. Such retention of platinum may lead to increased yields and / or less cost for replacement catalyst.

[0014] Without being bound by theory, it is believed that, according to one or more embodiments, the process for making the catalyst, as described herein, forms catalyst particles that are less prone to platinum loss in a cyclonic separation device or other separation device that attrites catalyst. In particular, platinum-containing catalyst may be prone to attrition and platinum loss in a cyclonic separation device following relatively high heat exposure in a reactor. The relatively high reactor temperatures may cause sintering of the platinum, a phenomenon whereby platinum single atoms, clusters (a few platinum atoms), or small Pt particles (e.g., less than 5 nm) agglomerate, forming larger platinum clusters or larger particles, and in many cases on the surface of the fluidized catalyst particles. This sintering, according to embodiments, affects platinum more than other components, and is believed to cause enhanced platinum loss when the catalyst is attrited during normal plant operations in, for example, a cyclonic separation device. It is believedthat the attriting procedure prior to platinum impregnation when making the catalysts, as described herein, forms catalyst particles with less sharp edges than conventional embodiments. That is, the pre-impregnation attrition reduces sharp edges on the catalyst that contain platinum, which may be prone to attrition in a cyclonic separation device and would otherwise be lost from the catalyst during utilization in a chemical conversion process.

[0015] As described, and according to embodiments, the methods for making a catalyst may comprise, as an initial step, attriting initial support particles. The initial support particles, as described herein, are support particles prior to impregnation platinum. According to embodiments, the initial support particles may be fabricated by a user or may be purchased from a commercial vendor. According to embodiments, the initial support particle may comprise or consist of alumina. However, other support materials are contemplated, such as silicates, aluminosilicates, tinanosilicates, zirconium-containing materials, and other suitable support materials. In some embodiments, the initial support particles may be formed by spray drying of colloidal alumina.

[0016] According to embodiments, the initial support particles (as well as all other particles described herein) may include a distribution of particle sizes. Throughout this disclosure, particle size is measured according to ASTM D4464-15, “Standard Test Method for Particle Size Distribution of Catalytic Materials by Taser Tight Scattering”, 2015. Generally, the initial support particles may include particles having about the size desired for use in a chemical processing system, such as a size that is fluidizable, such as meeting the standards of Geldart A or Geldart B fluidization. According to embodiments, at least a portion of the initial support particles (such as all of the initial support particles) may have a size of greater than 10 microns. Additionally, in some embodiments, the initial support particles may include fines. Fines, as described herein, refer to particles having a size of less than 10 micron. In some embodiments, the majority (such as at least 75% at least 90%, or even at least 95%) of the initial support particles (by volume percent) may have a size of greater than 10 microns. According to embodiments, the initial support particles may a median particle size (or may have a peak in particle size distribution) of from 25 microns to 200 microns, such as from 50 microns to 150 microns. As described throughout this disclosure, the median particle size, also known as a D50, is the particle size at which 50% of particles by mass (and volume) are smaller than this size.

[0017] According to one or more embodiments, the attriting of the initial support particles may form attrited support particles and fines. As described herein, attriting generally refers to making the bodies of the initial support particles smaller through attrition, generally by rubbing and / or wearing down by friction. Generally, and according to one or more embodiments, the initial support particles may comprise particles having relatively jagged or sharp geometric forms or possess jagged or sharp surface irregularities, as compared with the attrited support particles following the attriting process.

[0018] In one or more embodiments, the attriting may comprise processing by, without limitation, jet cup, jet mill, media mill, ball mill, impact mill, and / or fluid energy mill. However, other mechanical attrition techniques are contemplated, and the attrition technique utilized is not necessarily limited in the embodiments described herein. In general, the attriting does not change the chemical composition of the precursor support material, but affects the shape and / or size of the initial support particles.

[0019] The attriting of the initial support particles may form attrited support particles and additional fines not included in the initial support particles. The fines, as described herein, have a particle size of less than 10 microns, and the attrited support particles have a particle size of at least 10 microns. In some embodiments, at least 0.25 wt.%, at least 0.5 wt.%, at least 1 wt.%, at least 2 wt.%, or even at least 3 wt.% of the total mass of the initial support particles may be converted into fines by attrition.

[0020] According to embodiments, at least a portion of the fines may be separated from the attrited support particles. For example, in some embodiments, only a portion of the fines are separated from the attrited support particles, such as at least 50 wt.%, at least 75 wt.%, at least 90 wt.%, or even at least 95 wt.%. Some fines may still be present mixed with the attrited support particles during impregnation. Additionally, according to embodiments, a portion of the attrited support particles may be separated, particularly the smaller sized attrite support particles. For example, a good deal of attrited support particles having a particle size of less than 20 microns may be separated from the remainder of the attrited support particles along with the fines. A variety of separation techniques may be suitable, such as any that separate by particle size, without limitation, including cyclonic separation device (sometimes known as cyclones in industry), air classifiers, sieves, or other filters. In some embodiments, the separation step and attrition step maybe carried out by the same process and / or apparatus (e.g., a cyclonic separation device). Cyclonic separation devices, as described herein, 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. These cyclonic separation devices may be utilized for the pre-impregnation attrition of support particles as well as during chemical processing to separate catalyst from gaseous products.

[0021] Without being bound by theory, about 10 microns or about 20 microns may be about the threshold in which particles pass out of a cyclonic separation device with the fluid (nonsolids). Thus, the fines that would be immediately expelled from a reactor system may be discarded and never introduced to the system. It is contemplated that, according to some embodiments, fines having a size greater than 10 microns may also be separated from the attrited support particles that are later impregnated.

[0022] According to embodiments, following the separating of the fines (and, in some embodiments, a portion of the attrited support particles) from the remaining attrited support particles, at least a portion of the attrited support particles may be impregnated with at least platinum. The attrited support particles may also be impregnated with at least another metal, such as gallium. In additional embodiments, other metals may be additionally impregnated into the attrited support particles. The platinum and gallium may be impregnated in separate impregnation steps or in a single impregnation step. In some embodiments, fines may be present with the attrited support particles, and may also be impregnated.

[0023] Generally, the portion of the attrited support particles that are impregnated (as well as the final catalyst) may include particles having about the size desired for use in a chemical processing system, such as a size that is fluidizable, such as meeting the standards of Geldart A or Geldart B fluidization. According to embodiments, the attrited support particles that are impregnated (as well as the final catalyst) may an median particle size (or may have a peak in particle size distribution) of from 25 microns to 200 microns, such as from 50 microns to 150 microns, with a minimal amount of fines less than 10 microns in size (for example, less than 1 wt.% fines).

[0024] As described hereinabove, the catalyst can be prepared by impregnation. The impregnation may utilize incipient wetness impregnation (sometimes referred to as dry impregnation or capillary impregnation) or wet impregnation. Typically, in incipient wetness impregnation, the metal precursor is dissolved in an aqueous or organic solution. Then the metalcontaining solution is contacted with the catalyst support (the “attrited support material” in the presently disclosed embodiments) containing the about the same pore volume as the volume of the solution that is added. Capillary action may draw the solution into the pores. Solution added in excess of the support pore volume may cause the solution transport to change from a capillary action process to a diffusion process, which is generally much slower.

[0025] As described herein, the impregnation may utilize an aqueous solution that includes compounds that include the impregnated materials, referred to herein as precursors. For example, platinum precursors include platinum and gallium precursors include gallium. In various embodiments, the aqueous solution may comprise the one or more precursors of gallium and / or platinum. Examples of platinum precursors include, without limitation, platinum(IV) nitrate, Tetraammineplatinum(II) nitrate, and Chloroplatinic acid, and examples of gallium precursors include gallium (III) nitrate, gallium (III) chloride, and Gallium(III) sulfate. In some embodiments, multiple impregnation steps may occur to impregnate different materials.

[0026] In one or more embodiments, the impregnated support particles may be dried at an elevated temperature, such as a temperature of less than 200 °C, less than 175 °C, less than 150 °C, less than 125 °C, less than 100 °C, less than 75 °C, or even less than 50 °C. In certain embodiments, impregnation can be done more than once with the solution, and the impregnated support particles may be dried between each impregnation prior to the exposing of the impregnated support particles to the temperature of from 400 °C to 1000 °C.

[0027] The dried impregnated support particles may then be exposed to a temperature of from 400 °C to 1000 °C. The elevated temperature exposure may calcine the impregnated support particles to produce the catalyst. In one or more embodiments, the calcination may be at a temperature of greater than 500 °C, such as greater than 600 °C, greater than 700 °C, greater than 800 °C, or even greater than 900 °C. In one or more embodiments, the impregnated support particles may be calcined under air. In embodiments where multiple impregnation steps are utilized, the impregnated support particles may be calcined between each impregnation. Inembodiments, the dried impregnated material may be calcined in air for more than 1 hour. For example, the dried impregnated material may be calcined in air for more than 20 min, more than 1 hour, more than 2 hours, more than 4 hours, or even more than 10 hours.

[0028] In general, the catalyst may include the materials of the initial support particles (resized / reshaped following the attriting process) and one or more active metals such as platinum and gallium. According to embodiments, the initial support particle may comprise or consist of alumina. However, other support materials are contemplated, such as silicates, aluminosilicates, tinanosilicates, zirconium-containing materials, and other suitable support materials. The support may be present in the catalyst in an amount of at least 85 wt.%.

[0029] In one or more embodiments, the catalyst may comprise platinum in an amount from 10 ppmw to 500 ppmw based on the total mass of the catalyst. Platinum may catalyze the dehydrogenation of propane to propylene particularly when used in combination with gallium. For example, the catalyst may comprise platinum in an amount from 10 ppmw to 25 ppmw, from 25 ppmw to 50 ppmw, from 50 ppmw to 100 ppmw, from 100 ppmw to 150 ppmw, from 150 ppmw to 200 ppmw, from 200 ppmw to 250 ppmw, from 250 ppmw to 300 ppmw, from 300 ppmw to 350 ppmw, from 350 ppmw to 400 ppmw, from 400 ppmw to 450 ppmw, from 450 ppmw to 500 ppmw, or any combination of these ranges. In some embodiments, the catalyst may comprise platinum in an amount from 10 ppmw to 450 ppmw, from 25 ppmw to 350 ppmw, from 50 ppmw to 300 ppmw, from 75 ppmw to 250 ppmw, or from 100 ppmw to 200 ppmw. Without being bound by theory, it is believed that compositions having platinum in an amount less than 10 ppmw may negatively impact the catalyst’s ability to catalyze the propane dehydrogenation process by lowering both the percentage of total propane dehydrogenated and the percentage of dehydrogenated propane that forms propylene. However, it is believed that compositions having platinum in an amount exceeding 500 ppmw does not further enhance the catalyst’s ability to catalyze the propane dehydrogenation process, nor improve the catalyst’s selectivity towards propylene, or both.

[0030] According to some embodiments, the catalyst may comprise gallium in an amount from 0.1 wt.% to 10 wt.% based on the total mass of the catalyst. Gallium may catalyze the dehydrogenation of alkanes to alkenes, particularly when used in combination with platinum. For example, the catalyst may comprise gallium in an amount from 0.1 wt.% to 0.25 wt.%, from 0.25wt.% to 0.5 wt.%, from 0.5 wt.% to 0.75 wt.%, from 0.75 wt.% to 1 wt.%, from 1 wt.% to 2 wt.%, from 2 wt.% to 3 wt.%, from 3 wt.% to 4 wt.%, from 4 wt.% to 5 wt.%, from 5 wt.% to 6 wt.%, from 6 wt.% to 7 wt.%, from 7 wt.% to 8 wt.%, from 8 wt.% to 9 wt.%, from 9 wt.% to 10 wt.%, or any combination of these ranges. In some embodiments, the catalyst may comprise gallium in an amount from 0.1 wt.% to 9 wt.%, from 0.1 wt.% to 8 wt.%, from 0.1 wt.% to 7 wt.%, from 0.1 wt.% to 6 wt.%, or from 0.1 wt.% to 5 wt.%.

[0031] In general, the amount of platinum, gallium, or any other active metal may be selected by the amount of metal precursor used during impregnation.

[0032] In one or more additional embodiments, the catalyst may optionally comprise one or more alkali metals, one or more alkaline earth metals, or both, in an amount from 0.01 wt.% to 5 wt.% based on the total weight of the catalyst. For example, the catalyst may comprise one or more alkali metals, one or more alkaline earth metals, or both in an amount from 0.01 wt.% to 0.05 wt.%, from 0.05 wt.% to 0.1 wt.%, from 0.1 wt.% to 0.2 wt.%, from 0.2 wt.% to 0.3 wt.%, from 0.3 wt.% to 0.4 wt.%, from 0.4 wt.% to 0.5 wt.%, from 0.5 wt.% to 0.6 wt.%, from 0.6 wt.% to 0.7 wt.%, from 0.7 wt.% to 0.8 wt.%, from 0.8 wt.% to 0.9 wt.%, from 0.9 wt.% to 1 wt.%, from 1 wt.% to 2 wt.%, from 2 wt.% to 3 wt.%, from 3 wt.% to 4 wt.%, from 4 wt.% to 5 wt.%, or any combination of these ranges. In some embodiments, the catalyst may comprise one or more alkali metals, one or more alkaline earth metals, or both from 0.01 wt.% to 1 wt.%, from 0.02 wt.% to 0.75 wt.%, from 0.03 wt.% to 0.5 wt.%, from 0.04 wt.% to 0.4 wt.%, or from 0.05 wt.% to 0.3 wt.%. In some embodiments, the one or more alkali metals or one or more alkaline earth metals may be potassium. However, it is believed that compositions having alkali metals or alkaline earth metals in an amount exceeding 5 wt.% may reduce the catalyst’s dehydrogenation activity.

[0033] In one or more embodiments, the catalyst may be capable of fluidization. In some embodiments, the catalyst may have a median particle size (D50) of from 50 pm to 300 pm, such as from 50 pm to 250 pm, from 50 pm to 200 pm, from 50 pm to 150 pm, from 50 pm to 100 pm, from 100 pm to 300 pm, from 100 pm to 250 pm, from 100 pm to 200 pm, from 100 pm to 150 pm, from 150 pm to 300 pm, from 150 pm to 250 pm, from 150 pm to 200 pm, from 200 pm to 300 pm, from 200 pm to 250 pm, or from 250 pm to 300 pm.

[0034] In some embodiments, the catalyst may exhibit properties known in the industry as “Geldart A” or “Geldart B” properties. Particles may be classified as “Group A” or “Group B” according to D. Geldart, Gas Fluidization Technology, John Wiley & Sons (New York, 1986), 34- 37; and D. Geldart, “Types of Gas Fluidization,” Powder Technol. 7 (1973) 285-292, which are incorporated herein by reference in their entireties.

[0035] Group A is understood by those skilled in the art as representing an aeratable powder, having a bubble-free range of fluidization; a high bed expansion; a slow and linear deaeration rate; bubble properties that may include a predominance of splitting / recoalescing bubbles, with a maximum bubble size and large wake; high levels of solids mixing and gas backmixing, assuming equal U-Umf (U is the velocity of the carrier gas, and Umf is the minimum fluidization velocity, typically though not necessarily measured in meters per second, m / s, i.e., there is excess gas velocity); axisymmetric slug properties; and no spouting, except in very shallow beds. The properties listed tend to improve as the mean particle size decreases, assuming equal cfp; or as the <45 micrometers (pm) proportion is increased; or as pressure, temperature, viscosity, and density of the gas increase. In general, the particles may exhibit a small mean particle size and / or low particle density (<1.4 grams per cubic centimeter, g / cm3), fluidize easily, with smooth fluidization at low gas velocities, and may exhibit controlled bubbling with small bubbles at higher gas velocities.

[0036] Group B is understood by those skilled in the art as representing a “sand-like” powder that starts bubbling at Umf; that exhibits moderate bed expansion; a fast deaeration; no limits on bubble size; moderate levels of solids mixing and gas backmixing, assuming equal U- Umf; both axisymmetric and asymmetric slugs; and spouting in only shallow beds. These properties tend to improve as mean particle size decreases, but particle size distribution and, with some uncertainty, pressure, temperature, viscosity, or density of gas seem to do little to improve them. In general, most of the particles having a particle size (cfp) of 40 pm <cfp <500 pm when the density (pp) is 1.4 <pp <4 g / cm3, and preferably 60 pm <cfp <500 pm when the density (pp) is 4 g / cm3 and 250 pm <cfp <100 pm when the density (pp) is 1 g / cm3.

[0037] In one or more embodiments, the catalysts formed from the methods described herein may be used in the reactor system of FIG. 1 operating as a fluidized dehydrogenation reactor system to produce light olefins, such as propylene. However, it should be understood thatthe 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 catalysts formed by the methods described herein are now described as being utilized in the context of FIG. 1, such catalysts should be understood as adaptable to other systems, as would be understood by those skilled in the art.

[0038] Now referring to FIG. 1, an example reactor system 102 that may be suitable for use with the catalysts described herein is schematically depicted. The reactor system 102 generally comprises multiple system components, such as a reactor portion 200 and a catalyst processing portion 300. As described herein, “system components” refer to portions of the reactor system 102, 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 reactor system 102 in which the major process reaction takes place (e.g., dehydrogenation) to form the olefin- containing effluent. A hydrocarbon-containing feed enters the reactor portion 200, is contacted with a catalyst, converted to an olefin-containing 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 olefin-containing effluent formed in the reactor 202. Also, as used herein, the catalyst processing portion 300 generally refers to the portion of the reactor system 102 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).

[0039] Generally, as is described herein, in embodiments illustrated in FIG. 1, catalyst is cycled between the reactor portion 200 and the catalyst processing portion 300. It should beunderstood that when “catalysts” are referred to herein, they may refer to solid materials that are catalytically active for a desired reaction including the catalysts produced from the methods of the present disclosure. The terms “catalytic activity” and “catalyst activity” refer to the degree to which the catalyst is able to catalyze the reactions conducted in the reactor system 102. 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 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.

[0040] In non-limiting examples, the reactor system 102 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 such embodiments, the hydrocarbon-containing feed may comprise one or more of, ethane, propane, n-butane, and i- butane. 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 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. 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 i-butane. In additional embodiments, the hydrocarbon-containing feed may comprise at least 50 wt.%, at least60 wt.%, at least 70 wt.%, at least 80 wt.%, at least 90 wt.%, at least 95 wt.% or even at least 99 wt.% of the sum of ethane, propane, n-butane, and i-butane.

[0041] As described with respect to FIG. 1, the hydrocarbon-containing feed may enter feed inlet 434 into the reactor 202, and the olefin-containing effluent may exit the reactor system 102 via pipe 420. According to one or more embodiments, the reactor system 102 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.

[0042] 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.

[0043] 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 theupstream 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. 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.

[0044] 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 transport velocity, where the gas and catalyst have about the same velocity in a dilute phase.

[0045] Reaction temperatures in the upstream reactor section 250 and the downstream reactor section 230 may be relatively high, such as at least 500 °C, at least 600 °C, at least 700 °C, at least 800 °C, or even at least 900 °C. Such temperatures may cause sintering of the catalyst, and particularly sintering of the platinum in the catalyst.

[0046] According to embodiments, the olefin-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.

[0047] 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.

[0048] The separation device 220, comprising one or more cyclones, may attrite the catalyst and form fines (such as about 20 microns or less). The fines may exit with the product. Such fines may carry away platinum in higher amounts than other materials, detrimentally affecting catalytic activity. The catalysts described herein may mitigate fine formation from attrition in the cyclone due to their reduced sharp edges.

[0049] Still referring to FIG. 1 , the separated catalyst is passed from the catalyst separation section 210 to the combustor 350. In the combustor 350, the catalyst may be processed by, forexample, combustion of coke with oxygen. 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 olefin-containing effluent may be gaseous, and the catalyst may be fluidized particulate solid.

[0050] Similar to as described with respect to the reactor portion 200, relatively high temperatures in the combustor 350 followed by attrition in the secondary separation device 320, such as a cyclonic separation device, may cause fine formation and enhanced platinum loss in conventional catalysts.

[0051] 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. 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 riser330. 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.

[0052] 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 is conducted in the oxygen treatment zone 370. 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 oxygen-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.

[0053] In one or more embodiments, the light olefins may be present in a “product stream” sometimes called an “olefin-containing effluent” and include light olefins. Such a stream exits the reactor system of FIG. 1 and may be subsequently processed. As used in the present disclosure, the term “light olefins” refers to one or more of ethylene, propylene, and butene. The term butene includes any isomers of butene, such as a-butylene, cis-P-butylene, trans-P-butylene, and isobutylene. In some embodiments, the olefin-containing effluent includes at least 25 wt.% light olefins based on the total weight of the olefin-containing effluent. For example, the olefin- containing effluent may include at least 35 wt.% light olefins, at least 45 wt.% light olefins, at least 55 wt.% light olefins, at least 65 wt.% light olefins, or at least 75 wt.% light olefins based on the total weight of the olefin-containing effluent. The olefin-containing effluent may further comprise unreacted components of the hydrocarbon-containing effluent, as well as other reaction products that are not considered light olefins. The light olefins may be separated from unreacted components in subsequent separation steps.

[0054] Numerous aspects are presented in the present disclosure, which are described as Aspects 1-20 hereinbelow.

[0055] Aspect 1. A method for making a catalyst, the method comprising: attriting initial support particles, wherein at least a portion of the initial support particles have a size of greaterthan 10 microns, wherein the attriting of the initial support particles forms at least: attrited support particles; and fines having a size of less than 10 microns; separating at least a portion of the fines from the attrited support particles; and impregnating at least a portion of the attrited support particles with at least platinum to form impregnated support particles; and exposing the impregnated support particles to a temperature of from 400 °C to 1000 °C to form the catalyst

[0056] Aspect 2. The method of any previous aspect, wherein the portion of the attrited support particles impregnated have a median particle size of greater than 25 microns.

[0057] Aspect 3. The method of any previous aspect, wherein at least 0.25 wt.% of the total mass of the initial support particles are converted into fines by the attrition.

[0058] Aspect 4. The method of any previous aspect, wherein impregnating the attrited support particles comprises contacting the attrited support material with a solution comprising one or more gallium precursors and one or more platinum precursors.

[0059] Aspect 5. The method of aspect 4, wherein the one or more gallium precursors are chosen from gallium (III) nitrate, gallium (III) chloride, and Gallium(III) sulfate.

[0060] Aspect 6. The method of aspect 4, wherein the one or more platinum precursors are chosen from platinum(IV) nitrate, Tetraammineplatinum(II) nitrate, and Chloroplatinic acid.

[0061] Aspect 7. The method of any previous aspect, wherein the attriting of the initial support particles comprises attrition utilizing jet cup, jet mill, media mill, ball mill, impact mill, and / or fluid energy mill, or combinations thereof.

[0062] Aspect 8. The method of any previous aspect, further comprising impregnating the attrited support particles with gallium.

[0063] Aspect 9. The method of any previous aspect, wherein the catalyst exhibits Geldart A or Geldart B fluidization properties.

[0064] Aspect 10. The method of any previous aspect, wherein the initial support particles comprise alumina.

[0065] Aspect 11. The method of any previous aspect, wherein the catalyst comprises: at least 85 wt.% alumina support material; from 10 ppmw to 500 ppmw of platinum; and from 0.1 wt.% to 10 wt.% of gallium.

[0066] Aspect 12. The method of aspect 11, wherein the catalyst further comprises from 0.01 wt.% to 5 wt.% of one or more alkali or alkaline earth metals.

[0067] Aspect 13. The method of any previous aspect, wherein the catalyst is active for dehydrogenation of alkanes.

[0068] Aspect 14. The method of any previous aspect, wherein the catalyst is utilized in a reactor system where it is exposed to temperature of at least 500 °C.

[0069] Aspect 15. The method of any previous aspect, wherein the catalyst is utilized in a reactor system comprising a cyclonic separation device.Examples

[0070] The various embodiments of the present disclosure will be further clarified by the following examples. The examples are illustrative in nature and should not be understood to limit the subject matter of the present disclosure.

[0071] Sample Cl was prepared utilizing the pre-impregnation attrition procedure described herein. A microspheroidal alumina support was prepared by spray drying a mixture of hydrated alumina and Tudox Colloidal Silica (commercially available from W.R. Grace and Co.) and then heating the resulting spray dried particles at a temperature of at least 1000 °C, sufficient to achieve particles with particle size ranging from 5 pm to 300 pm, pore volume of 0.20 ± 0.10 ml / g, surface area of 70 ± 20 m2 / g, and silica content 2.5 ± 2.5 wt.%. The alumina-based catalyst support was attrited in a jet cup attrition unit commercially available from PSRI (following the procedures described in R. Cocco, et al. Powder Technology 2010, 200, 224-233) at 300 ft / s for 6 hours at room temperature. Fines measuring under 20 micron and less, which was about 3% of initial material, were filtered away and discarded. The catalyst materials were prepared by an incipient wetness impregnation method to load the designated metal to the obtained support using nitrate or amine nitrate metal precursors followed by drying at temperatures less than 200 °C, and then calcination at temperatures less than 800 °C.

[0072] A comparative sample, C2, was prepared by the same method as used to prepare Cl, but the pre-impregnated support material was not attrited by jet cup attrition prior to impregnation.

[0073] FIGS. 2 and 3 depicts the particle size distribution of sample Cl after the preimpregnation attrition (before fines removal) and sample Cl after fines removal. Also shown is comparative sample C2, where no pre-impregnation attrition took place. FIG. 3 presents the same data as FIG. 2 but is zoomed in in a fines particle size region. In FIGS. 2 and 3, the particle quantity is shown by volume percent where particle size is measured logarithmically. As is depicted in FIGS. 2 and 3, attrition caused formation of fines having a size slightly greater than 1 micron, and the some of these fines are removed by separation.

[0074] The two catalyst samples (Cl and C2) were then tested for platinum retention following conditions similar to that would be experienced in some reactor systems. The samples Cl and C2 were subjected to a lab aging protocol, including calcination at 800 °C for 24 hours in furnace under air followed up by attrition in PSRI jet cup at 300 ft / s for 1 hour (simulating accelerated reactor conditions followed by attrition in a cyclone). The catalysts were then screened to different particle size ranges using a Rotap sieve shaker and characterized by an X-ray fluorescence (XRF) technique to quantify the % of platinum retained on catalyst, as shown in Table 1. The Pt retention [%] is defined as the percentage of Pt retained on certain particle sizes after lab aging over the Pt concentration of fresh catalyst of same particle size prior to lab aging.

[0075] An improvement of platinum retention on catalyst of Cl over C2 was observed in all particle size ranges above 20 microns (fines which would exit an industrial reactor system). Interestingly, the fines particles sized less than 20 pm had more than 100% of Pt retention, indicating that some Pt from inside of catalyst particles were migrated to the surface of catalyst particles, more prone to be removed through attrition and concentrated on the fines attrited from catalyst particles, thus removed from reactor system and causing bulk catalyst Pt loss. The non- pre-attrited sample C2 fines had a greater amount of platinum retention (i.e. more severe platinum migration) in the fines catalyst below 20 microns, confirming that sample Cl is superior to C2.Table 1

[0076] It will be apparent to those skilled in the art that various modifications and variations can be made to the presently disclosed technology without departing from the spirit and scope of the technology. Since modifications combinations, sub-combinations and variations of the disclosed embodiments incorporating the spirit and substance of the presently disclosed technology may occur to persons skilled in the art, the technology should be construed to include everything within the scope of the appended claims and their equivalents. Additionally, although some aspects of the present disclosure may be identified herein as favored or particularly advantageous, it is contemplated that the present disclosure is not limited to these aspects.

[0077] 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 illustratedin each of the drawings that accompany the present description. Unless specifically identified as such, no feature disclosed and described herein should be construed as “essential”. Contemplated embodiments of the present technology include those that include some or all of the features of the appended claims.

[0078] 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” is 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.

[0079] In relevant cases, where a composition is described as “comprising” one or more elements, embodiments of that composition “consisting of’ or “consisting essentially of’ those one or more elements is contemplated herein.

[0080] It is noted that one or more of the following claims and the detailed description utilize the terms “where” or “wherein” as a transitional phrase. For the purposes of defining the present technology, it is noted that this term is introduced in the claims as an open-ended transitional phrase that is used to introduce a recitation of a series of characteristics of the structure and should be interpreted in like manner as the more commonly used open-ended preamble term “comprising.”

[0081] It should be understood that any two quantitative values assigned to a property may constitute a range of that property, and all combinations of ranges formed from all stated quantitative values of a given property are contemplated in this disclosure. Where multiple ranges for a quantitative value are provided, these ranges may be combined to form a broader range, which is contemplated in the embodiments described herein.

Claims

1. A method for producing a catalyst, comprising: abrading the initial carrier particles, wherein at least a portion of the initial carrier particles have a size greater than 10 μm, wherein the abrading of the initial carrier particles results in the formation of at least: abraded particles of the carrier; and small particles less than 10 microns in size; separating at least a portion of the fine particles from the attrited carrier particles; impregnating at least a portion of the attrited carrier particles with at least platinum to form impregnated carrier particles; and exposure of impregnated carrier particles to temperatures ranging from 400°C to 1000°C to produce a catalyst.

2. The method according to any of the preceding claims, wherein the portion of the abraded carrier particles subjected to impregnation has a median particle size greater than 25 µm.

3. The method according to any one of the preceding claims, wherein at least 0.25% by weight of the total weight of the initial carrier particles is converted into fine particles as a result of attrition.

4. The method according to any one of the preceding claims, wherein impregnating the attrited carrier particles comprises contacting the attrited carrier material with a solution containing one or more gallium precursors and one or more platinum precursors.

5. The method according to claim 4, wherein one or more gallium precursors are selected from gallium(III) nitrate, gallium(III) chloride and gallium(III) sulfate.

6. The method according to claim 4, wherein one or more platinum precursors are selected from platinum(IV) nitrate, tetraammineplatinum(II) nitrate and chloroplatinic acid.

7. The method according to any one of the preceding claims, wherein the attrition of the initial carrier particles comprises attrition using a jet nozzle, a jet mill, a grinding media mill, a ball mill, an impact mill and / or a mill using the energy of the working medium, or combinations thereof.

8. The method according to any one of the preceding claims, further comprising impregnating the abraded carrier particles with gallium.

9. The method according to any of the preceding claims, wherein the catalyst exhibits Geldart type A or type B fluidization properties.

10. The method according to any one of the preceding claims, wherein the initial carrier particles comprise aluminum oxide.

11. The method according to any one of the preceding claims, wherein the catalyst comprises: at least 85% by weight of the carrier material based on aluminum oxide; from 10 ppm to 500 ppm of platinum; and from 0.1 wt.% to 10 wt.% gallium.

12. The method according to claim 11, wherein the catalyst additionally contains from 0.01 wt.% to 5 wt.% of one or more alkali or alkaline earth metals.

13. The method according to any of the preceding claims, wherein the catalyst is active in the dehydrogenation reaction of alkanes.

14. The method according to any one of the preceding claims, wherein the catalyst is used in a reactor system where it is exposed to a temperature of at least 500 °C.

15. The method according to any one of the preceding claims, wherein the catalyst is used in a reactor system comprising a cyclonic separation device.