Zeolite catalyst having paired heteroatoms and method thereof

Abstract

The present disclosure relates to zeolite catalysts with aging durability and improved catalytic activity. For example, the zeolite catalysts include a specific aluminum distribution, such as the positioning of two framework aluminum atoms in the zeolite structure at third nearest neighbor (3NN) relative positions in the framework. The zeolite catalysts have two tetrahedrally coordinated Al sites separated by two tetrahedrally coordinated Si sites. The present disclosure is also directed to processes and methods for their characterization and use.

Description

[Technical Field]

[0001] This application claims priority to U.S. Patent Application No. 63 / 263,599, filed on November 5, 2021, and this disclosure is incorporated herein by reference in its entirety.

[0002] This disclosure relates to zeolite catalysts having aging durability and improved catalytic activity. For example, the zeolite catalyst includes a specific aluminum distribution, i.e., the positioning of two aluminum atoms in the zeolite structure at 3NN relative positions. The zeolite catalyst has two tetrahedral Al moieties separated by two tetrahedral Si moieties. This disclosure also covers processes and methods for their characterization and use.

[0003] Molecular sieves such as zeolites are treated with reducing agents such as ammonia, urea, or hydrocarbons to remove nitrogen oxides (NOx). x Zeolites have been used in selective catalytic reduction (SCR). Zeolites are crystalline materials with fairly uniform pore sizes ranging from approximately 3 to 25 angstroms in diameter, depending on the type of zeolite and the type and number of cations contained in the zeolite lattice. Zeolites with 8-membered ring pore openings and double 6-membered ring secondary structural units, such as cage-like structures, are of interest as SCR catalysts. The number of rings refers to the number of atoms coordinated in an almost tetrahedral manner in the interconnected rings of the zeolite skeleton. Zeolites with a chabazite (CHA) crystal structure are included in this category, which are small-pore zeolites with 8-membered ring pore openings (approximately 3.8 angstroms) and accessible by their three-dimensional porosity. The cage-like structure arises from the linkage of double 6-membered ring structural units by 4-membered rings.

[0004] Chabazite (CHA) zeolite catalyst is NO xThe selective catalytic reduction (SCR) of Al is attracting attention. The amount of Al may play a role in the reaction properties and stability of the zeolite framework, but currently there is no way to provide direct evidence to determine the location of Al within the zeolite framework, and it is unclear what kind of role the Al distribution plays and to what extent it affects the reaction properties.

[0005] Metal-promoted zeolite catalysts are also often called ion-exchanged zeolites or copper and / or iron-supported zeolites. Copper-promoted and iron-promoted zeolite catalysts for SCR of nitrogen oxides by ammonia are particularly well known and can typically be prepared via metal ion exchange processes. However, it has been found that the activity of many metal-promoted zeolites begins to decrease under harsh hydrothermal conditions. This decrease in activity is thought to be due to the destabilization of the zeolite, such as dealuminization or reduction of the metal-containing catalytic sites within the zeolite.

[0006] Ideally, catalysts used in SCR processes should be able to maintain high catalytic activity under hot water conditions and over a wide range of operating temperature conditions, such as approximately 150°C to over 600°C. Hot water conditions are encountered in reality because water is a byproduct of fuel combustion, and high-temperature hot water conditions occur in diesel exhaust applications, such as during the regeneration of soot filters, which are components of exhaust gas treatment systems used to remove carbonaceous particles.

[0007] The SCR process uses nitrogen oxides (NO x ) is converted to nitrogen (N2) and water (H2O). NO to N2 in the internal combustion engine exhaust flow while minimizing the formation of undesirable N2O. x It is desirable that a selective conversion of (NO + NO2) occurs. Undesirable N2O formation can be observed as a mole percent conversion of (NO + NO2) to N2O. Nitrogen oxide (NO x ) may include N2O, NO, N2O3, NO2, N2O4, N2O5, or NO3.

[0008] Zeolites, such as aluminosilicate zeolites, are of considerable technological interest because their high surface area, well-defined subnanometer pores, and cation-exchange sites enable catalytic applications for hydrocarbon conversion or pollution reduction. The catalytic properties of zeolites arise from the nonstoichiometric substitution of AlO4 tetrahedra for SiO4 tetrahedra, which introduces a negative framework charge that is balanced by exchangeable cations. Aluminosilicate zeolites, such as faujasite (Y zeolite) and chabazite (CHA, zeolite SSZ-13), are highly active as heterogeneous catalysts for hydrocarbon rearrangement reactions, including cracking or the conversion of methanol to light olefins, in their solid acid (H + ) form. In their metal-exchanged forms, aluminosilicate zeolites are of interest as catalysts for reducing NO x emissions in automotive exhaust streams by converting NO x compounds to N2 and H2O in the presence of a sacrificial reductant. Examples of metal-exchanged forms for this application include copper and iron. Different copper-exchanged zeolites exhibit very different reactivities, which are poorly understood at the atomic level. Among the reasons for such differences are, in many cases, the distinct local compositions and atomic environments of framework heteroatoms, such as aluminum, that directly affect the distribution of exchangeable cations, which are catalytically important sites. Measuring and understanding the influence of framework heteroatom environments on catalytic activity and selectivity has been difficult, partly due to the disordered distribution of heteroatoms within the zeolite framework that hinders detailed analysis by conventional scattering or spectroscopic techniques. In contrast, solid-state nuclear magnetic resonance (NMR) spectroscopy is sensitive to the local chemical environment of NMR-active species (e.g., 1 H, 27 Al, and 29 Si) in aluminosilicate zeolites. Using solid-state NMR spectroscopy, different types of 27 Al and 29 Si species can be identified, and their relative amounts and proximities, including to exchangeable copper cations, can be established.

[0009] For example, it is desired to prepare improved zeolite catalysts with higher hydrothermal stability for the conversion of methanol or propanol to olefins. Additionally, it is desired to prepare improved zeolite catalysts with higher catalytic activity and selectivity. This disclosure provides zeolite catalysts having aging durability and improved catalytic activity. For example, the zeolite catalyst involves a specific aluminum distribution, i.e., the positioning of two tetrahedral-coordinated aluminum atoms in a region of the zeolite structure separated by two Si tetrahedral sites, and at a third-nearest-neighbor (3NN) relative position. This disclosure also covers processes and methods for their characterization and use.

[0010] This disclosure generally provides a zeolite catalyst having paired skeletal aluminum atoms, wherein the paired aluminum atoms are third nearest neighbors (3NN) in the zeolite structure, and the zeolite catalyst has aging durability, improved catalytic activity, or a combination thereof.

[0011] In some embodiments, the zeolite catalyst is a CHA zeolite catalyst.

[0012] In some embodiments, the zeolite catalyst is a CHA zeolite catalyst, and the CHA zeolite catalyst is a copper-CHA catalyst.

[0013] In some embodiments, the zeolite in the zeolite catalyst composition is a micropore zeolite.

[0014] In some embodiments, the pore zeolite of the zeolite catalyst composition is of the AEI zeolite skeleton type.

[0015] In some embodiments, the pore zeolite of the zeolite catalyst composition is of the AFX zeolite skeleton type.

[0016] In some embodiments, the pore zeolite of the zeolite catalyst composition is of the AFT zeolite skeleton type.

[0017] In some embodiments, the zeolite catalyst is 2D 29 Si- 29 When measured using Si J-mediated NMR, the single quantum (SQ) dimension was -104 ppm (i.e., Hz / 10). 6 Hz ~ -108 ppm and double quantum (DQ) dimensions in the range of -208 ~ -212 ppm 29 Exhibits a Nu signal 29 It has a Si NMR signature.

[0018] In some embodiments, the zeolite is solid phase 2D 27 Al 29 When measured using Si}J-mediated heteronuclear multiple-quantum correlation (HMQC) NMR, 29 In the Si dimension, -98 ppm to -100 ppm, 27 In the Al dimension, in the range of 55-60 ppm 29 It has a Si NMR signature.

[0019] In some embodiments, the zeolite catalyst exhibited aging durability after 800°C hot water aging, and the zeolite catalyst had a 10% higher NO content compared to zeolites that did not contain the 3NN moiety. x It exhibits a transformation.

[0020] In some embodiments, the zeolite catalyst exhibits age resistance after hot water aging at 850°C, and the zeolite catalyst contains at least 50% NO x It exhibits a transformation.

[0021] In some embodiments, zeolite catalysts exhibit improved catalytic activity for methanol dimerization, with approximately 10% higher conversion rates compared to zeolites that do not contain the 3NN moiety.

[0022] In some embodiments, the zeolite catalyst has an SiO2 / Al2O3 ratio (SiO2 / Al2O3 ratio, SAR) selected from 8-40, 10-30, or 11-25.

[0023] In some embodiments, the zeolite catalyst further comprises copper (Cu) having a Cu content corresponding to a Cu / Al ratio selected from 0.2-0.5, 0.25-0.45, or 0.3-0.4.

[0024] In some embodiments, the catalytic article filters nitrogen oxides (NOx) from the exhaust gas of a lean-burn engine. x Effective in reducing ), the catalyst article comprises a substrate carrier having a selective catalytic reduction (SCR) catalyst, including a zeolite catalyst.

[0025] In some embodiments, the substrate carrier in the SCR catalyst is a honeycomb substrate, which is optionally composed of a metal or a ceramic.

[0026] In some embodiments, the honeycomb substrate carrier in the SCR catalyst is a flow-through substrate or a wall-flow filter.

[0027] In some embodiments, the exhaust gas treatment system comprises a lean-burn engine that generates an exhaust flow, and an SCR catalyst positioned downstream of the lean-burn engine and in fluid communication with the exhaust flow.

[0028] In some embodiments, the exhaust gas treatment system is as follows: The system further comprises one or more of the following: a diesel oxidation catalyst (DOC) positioned upstream of the SCR catalyst article, a soot filter positioned upstream of the catalyst article, and an ammonia oxidation catalyst (AMOX) positioned downstream of the catalyst article.

[0029] In some embodiments, the process for preparing a diesel oxidation catalyst (DOC) is as follows: The process includes: producing a zeolite catalyst composition; applying the catalyst as a coating onto a ceramic or metal honeycomb monolith substrate; drying the coated monolith; and firing the coated monolith at a temperature in the range of 400°C to 800°C.

[0030] These and other features, aspects, and advantages of this disclosure will become apparent from reading the following detailed description, along with the accompanying drawings which are briefly described below. Other aspects and advantages of the subject matter disclosed will become apparent from the following. [Brief explanation of the drawing]

[0031] To provide an understanding of embodiments of this disclosure, accompanying drawings are referenced, with reference numbers indicating components of exemplary embodiments of the subject matter disclosed. The drawings are illustrative only and should not be construed as limiting to this disclosure. The disclosures described herein are illustrated, not as limitations, in the accompanying drawings. For simplicity and clarity, the features illustrated in the drawings are not necessarily drawn to scale. For example, the dimensions of some features may be exaggerated relative to others for clarity. Furthermore, where appropriate, reference labels are repeated between drawings to indicate corresponding or similar elements. [Figure 1A] This is a typical 1D direct excitation insight 13C MAS NMR spectrum of methanol, which reacts on the dehydrated H+ forms of samples A and B in a sealed NMR rotor at 150°C to form dimethyl ether. [Figure 1B] As shown in Figure 1(A), this is the time-dependent methanol conversion for samples A and B at 125°C and 150°C, tracked by direct excitation 13C NMR. [Figure 1C] This is NOx conversion data for samples C, D, and G. [Figure 1D]This is N2O selectivity data for samples C, D, and G. [Figure 1E] This is NOx conversion data for samples A and B. [Figure 2A] This is a 1D direct excitation 29Si MAS NMR spectrum. [Figure 2B] These are the 1D direct excitation 27Al MAS NMR spectra of the hydrated H+ morphology of samples A and B. [Figure 3A] This is the 2D29Si{29Si}J-mediated single-quantum double-quantum (SQ-DQ) NMR spectrum of the hydrated H+ form of sample A. [Figure 3B] This is the 2D29Si{29Si}J-mediated SQ-DQ NMR spectrum of the hydrated H+ form of sample B. [Figure 4A] This is the 2D27Al{29Si}J-mediated HQMC NMR spectrum of sample A in its hydrated H+ form. The 1D29Si{1H} cross-polarization magic angle rotation (CP-MAS) spectrum obtained under the same conditions for sample A is shown along the vertical axis of each 2D spectrum. [Figure 4B] This is the 2D27Al{29Si}J-mediated HQMC NMR spectrum of sample B in its hydrated H+ form, and the 1D29Si{1H}CP-MAS spectrum obtained for sample B under the same conditions is shown along the vertical axis of each 2D spectrum. [Figure 5] This is a diagram of the catalytic site in aluminosilicate chabazite (SSZ-13). [Figure 6] This shows the structure of the "paired" Al skeleton related to the Cu2+-containing catalyst. [Figure 7A] This paper illustrates the differences in 29Si-O-29Si bonding properties revealed by 2D NMR. [Figure 7B] This is a schematic diagram illustrating the difference in 29Si-O-29Si bonding properties corresponding to the 2D NMR spectrum shown in Figure 7(A). [Figure 8] This is the 2D29Si{29Si}J-mediated solid-phase NMR spectrum of sample C in its hydrated H+ form. The spectrum was obtained at 9.4T, 8kHz MAS, and 100K. [Figure 9A]This is the 2D29Si{29Si} dipole-mediated solid-phase NMR spectrum of sample C in its hydrated H+ form. The spectrum was obtained at 9.4 T, 8 kHz MAS, and 100 K. [Figure 9B] This is the 2D29Si{29Si} dipole-mediated solid-phase NMR spectrum of the hydrated H+ form of sample D. The spectrum was obtained at 9.4 T, 8 kHz MAS, and 100 K. [Figure 10] This is the 2D29Si{29Si}J-mediated solid-phase NMR spectrum of the hydrated H+ form of sample D. The spectrum was obtained at 9.4T, 8kHz MAS, and 100K. [Figure 11] This is the 2D29Si{29Si}J-mediated solid-phase NMR spectrum of sample G in its hydrated H+ form. The spectrum was obtained at 9.4T, 8kHz MAS, and 100K.

[0032] Definition: As used herein, "a" or "an" entity refers to one or more entities; for example, "a compound" refers to one or more compounds or at least one compound unless otherwise specified. The terms "a" (or "an"), "one or more," and "at least one" are used interchangeably herein.

[0033] As used herein, “the molar percentage of [X] calculated based on the total number of moles of [X] and [Y]” refers to a percentage calculated, for example, in the context of nanoparticles, as follows:

[0034]

number

[0035] As used herein, the term “associated” means, i.e., “equipped,” “connected,” or “communicated,” for example, “electrically connected,” or “fluidally connected,” or otherwise connected to perform a function. As used herein, the term “associated” may mean directly or indirectly associated with one or more other articles or elements, i.e., associated through one or more other articles or elements.

[0036] As used herein, the term "AEI" refers to an AEI-type skeleton recognized by the International Zeolite Association (IZA) Structural Committee, and the term "AEI zeolite" refers to an aluminosilicate whose dominant crystalline phase is AEI.

[0037] As used herein, the term "AFX" refers to the AFX type skeleton recognized by the International Zeolite Association (IZA) Structural Committee, and the term "AFX zeolite" refers to silico-aluminophosphate 56.

[0038] As used herein, the term "AFT" refers to an AFT-type skeleton recognized by the International Zeolite Association (IZA) Structural Committee, and the term "AFT zeolite" refers to an AlPO4-52 catalyst.

[0039] As used herein, the term "BET surface area" has its usual meaning, referring to the Brunauer, Emmett, Teller method for determining the surface area of ​​porous materials by N2 adsorption. Pore diameter and pore volume can also be determined using BET-type N2 adsorption or desorption experiments.

[0040] As used herein, the terms “catalyst,” “catalyst material,” or “catalytic material” refer to a material that facilitates a reaction.

[0041] As used herein, the term “catalytic article” refers to an element used to promote a desired reaction. For example, a catalytic article may include a wash coat containing a catalyst species, such as a catalyst composition, on a substrate, such as a honeycomb substrate.

[0042] As used herein, the term "average particle size" refers to a particle characteristic that indicates the average diameter of the particles.

[0043] As used herein, the term “material” means an element, component, or substance from which something is composed or can be made.

[0044] As used herein, the term "nanoparticle" refers to a particle having at least one dimension in the range of 1 nm to 999 nm in length.

[0045] As used herein, "nitrogen oxides" or "NO x The term "nitrogen oxides" refers to nitrogen oxides.

[0046] As used herein, the term “particle size” refers to the smallest diameter sphere that completely encloses a particle, and this measurement relates to individual particles as opposed to aggregations of two or more particles. Particle size can be measured, for example, by laser light scattering techniques using dispersions or dry powders according to ASTM method D4464. Particle size can also be measured by scanning electron microscopy (SEM) or transmission electron microscopy (TEM) for submicron-sized particles, or by particle size analyzers for support-containing particles (micron size). In addition to TEM, carbon monoxide (CO) chemiadsorption can be used to determine the average PGM particle size. This technique does not distinguish between various PGM species (e.g., Pt, Pd, etc., compared to XRD, TEM, and SEM) and only determines the average particle size. As used herein, the term “room temperature” or “ambient temperature” refers to a temperature within the range of 15°C to 25°C, for example, 20°C to 25°C.

[0047] As used herein, the term “substantially” refers to a characteristic having a statistical occurrence rate greater than 75%.

[0048] As used herein, “support” in a catalyst material or catalyst washcoat refers to a material that accepts a catalyst (including, for example, a noble metal, stabilizer, co-catalyst, binder, etc.) through precipitation, association, dispersion, impregnation, or other suitable methods.

[0049] As used herein, the term “selective catalytic reduction” (SCR) refers to a catalytic process that uses a nitrogen reducing agent to reduce nitrogen oxides to dinitrogen (N2). The SCR process uses the catalytic reduction of nitrogen oxides with ammonia to form nitrogen and water.

[0050] As used herein, the term “washcoat” has the common meaning in the art of a thin, adhesive coating of a catalytic material or other material applied to a carrier substrate material, such as a honeycomb-type carrier member, which is sufficiently porous to allow the passage of a gas stream being processed. As understood in the art, a washcoat is obtained from a dispersion of particles in a slurry, which is applied to a substrate, dried, and calcined to provide a porous washcoat.

[0051] As used herein, the term "zeolite" refers to a specific example of a molecular sieve containing silicon and aluminum atoms. Zeolites are crystalline materials having fairly uniform pore sizes ranging in diameter from about 3 to 10 angstroms (Å), depending on the type of zeolite and the type and amount of cations contained in the zeolite lattice.

[0052] In more specific embodiments, the reference to the “aluminosilicate zeolite” skeleton type limits the material to molecular sieves that do not contain phosphorus or other metals substituted in the skeleton. However, for clarity, as used herein, “aluminosilicate zeolite” excludes aluminophosphate materials such as SAPO, ALPO, and MeAPO materials, and the broader term “zeolite” is intended to include aluminosilicates and aluminophosphates.

[0053] Zeolite CHA skeleton type molecular sieves are also referred to herein as "CHA zeolite."

[0054] As used herein, the term “enhanced” refers to a metallic component (“co-catalyst metal”) intentionally added to the molecular sieve material, as opposed to impurities inherent in the molecular sieve. Therefore, co-catalysts are intentionally added to enhance the catalytic activity compared to a catalyst without the intentionally added co-catalyst. In one or more embodiments, a suitable metal is independently replaced in the molecular sieve to promote the selective catalytic reduction of nitrogen oxides in the presence of ammonia. In some embodiments, copper (Cu) is, but is not limited to, a further co-catalyst metal that can be used to prepare the enhanced zeolite of the disclosed catalyst composition. The co-catalyst metal content, calculated as an oxide, is, in one or more embodiments, independently reported on a volatile-free basis, based on the total weight of the corresponding calcined zeolite (including the co-catalyst metal), ranging from about 0.01% to about 15% by weight, about 0.5% to about 12% by weight, or about 1.0% to about 10% by weight. In some embodiments, the co-catalyst metal is copper or iron. In some embodiments, both copper and iron are present as co-catalyst metals.

[0055] Zeolite catalyst This disclosure relates to a zeolite catalyst having aging durability and improved catalytic activity. For example, the zeolite catalyst includes a specific aluminum distribution, i.e., the positioning of two aluminum atoms in the zeolite structure at 3NN relative positions. The zeolite catalyst has two tetrahedral coordination Al moieties separated by two tetrahedral coordination Si moieties within the zeolite framework.

[0056] H + Cu 2+ Zn 2+The location and proximity of exchangeable cations, such as those mentioned above, depend on the location of Al heteroatoms in the zeolite framework. For example, paired Al heteroatoms located close to each other as second or third nearest neighbors in the aluminosilicate framework help stabilize divalent exchangeable cations. This stabilization creates improved chemical reaction properties. That is, the Al content and especially the distribution of paired Al moieties in the zeolite framework affect the conversion rate of methanol to olefins and the aluminosilicate zeolite H + / Cu 2+ - This affects the selectivity of the resulting product for the SSZ-13 catalyst. This is shown in Figure 5, which is a diagram of the catalytic site in aluminosilicate chabazite (SSZ-13).

[0057] In another example, NO in the vehicle exhaust stream x SCR for the contaminant species N2 and other products is Cu 2+ It depends on the pair of Al sites for replacement.

[0058] SAPO-34 and SSZ-13 are two CHA-structured catalysts that have been commonly studied for the reaction of methanol to olefins (methanol-to-olefin, MTO). SAPO-34 is commercially available for use in the MTO reaction, while SSZ-13 is a zeolite analogue of SAPO-34 and can exhibit selectivity for ethylene and propylene. Although SSZ-13 is a zeolite analogue of SAPO-34, it exhibits different reaction behavior, and this difference in reaction behavior is due to the Brønsted acid moiety. In both SSZ-13 and SAPO-34, the Brønsted acid moiety catalyzes the MTO reaction. A stronger Brønsted acid moiety is present in SSZ-13, which leads to increased coking and deactivation. The deactivation and product selectivity of both CHA-type catalysts are due to the acid moiety density. Increasing the Si / Al ratio in the SSZ-13 sample can increase catalyst stability and reaction time before deactivation.

[0059] Understanding and controlling the assembly and distribution of Al heteroatoms and associated cations in order to increase the number of paired skeletal Al moieties improves the catalytic properties of zeolite catalysts. 2+ An example of the structure of the "paired" Al skeleton of the catalyst is shown in Figure 6. Conventional methods for determining the collection and distribution of Al heteroatoms include elemental analysis and 1D solid-phase NMR. However, 1D solid-phase NMR provides only limited insight into Al positioning because the signals overlap, making it difficult to define connectivity between different sites.

[0060] This disclosure relates to a zeolite catalyst having aging durability and improved catalytic activity. For example, the zeolite catalyst includes a specific aluminum distribution, i.e., the positioning of two aluminum atoms in the zeolite structure at 3NN relative positions. The zeolite catalyst has two tetrahedral Al moieties separated by two tetrahedral Si moieties.

[0061] This disclosure relates, for example, to pairs of Al atoms separated as second or third nearest-nearest tetrahedron sites in the SSZ-13 zeolite framework, which leads to improved catalytic properties. This disclosure enables the design of catalysts with targeted reaction properties for reactions, for example, those involving adsorption processes in which divalent or trivalent cations have a significant influence.

[0062] In some embodiments, the disclosure relates to zeolite catalysts having paired aluminum atoms, where the paired aluminum atoms are separated as second or third neighbors in the zeolite structure. For example, different types 27 Al and 29 When identifying Si species, the focus is on zeolite catalysts containing paired aluminum atoms, with the aluminum atoms primarily being the third nearest neighbor (3NN). In the 3NN distribution, two tetrahedral Al moieties are separated by two tetrahedral Si moieties.

[0063] In some embodiments, the zeolite catalysts of the present disclosure have eight-membered ring pore openings and double six-membered ring secondary structural units, and zeolites having a cage-like structure in particular are suitable for use as SCR catalysts. In some embodiments, the zeolite catalyst of the present disclosure is chabazite (CHA), which is a microporous zeolite having an eight-membered ring pore opening (about 3.8 angstroms) accessible by its three-dimensional porosity. The cage-like structure arises from the bonding of double six-membered ring structural units by four-membered rings.

[0064] In some embodiments, the disclosure covers aluminosilicate zeolites, aluminosilicate zeolites having double-6-ring (D6R) structural units, microporous (8-membered ring pore open) aluminosilicate zeolites, microporous (8-membered ring pore open) aluminosilicate zeolites having double-6-ring (D6R) structural units, and chabazite zeolites. In some embodiments, the zeolite catalyst having Al atoms in a 3NN distribution may contain a metal such as copper, which can be introduced after the zeolite synthesis itself. In some embodiments, the Cu metal is also introduced during the synthesis of the zeolite.

[0065] In some embodiments, the disclosure relates to catalyst compositions comprising an aluminosilicate catalyst having paired aluminum atoms, wherein the paired aluminum atoms are separated as second or third proximitys in the aluminosilicate structure.

[0066] In some embodiments, the zeolite catalysts of the Disclosure include an SiO2 / Al2O3(SAR) ratio in the range of 8 to 40. In some embodiments, the zeolite catalysts of the Disclosure include an SiO2 / Al2O3(SAR) ratio in the range of 10 to 30, etc. In some embodiments, the zeolite catalysts of the Disclosure include an SiO2 / Al2O3(SAR) ratio in the range of 11 to 25.

[0067] In some embodiments, the zeolite catalysts of the Disclosure contain a Cu content corresponding to a Cu / Al ratio of about 0.2 to about 0.5. In some embodiments, the zeolite catalysts of the Disclosure contain a Cu content corresponding to a Cu / Al ratio of about 0.25 to about 0.45. In some embodiments, the zeolite catalysts of the Disclosure contain a Cu content corresponding to a Cu / Al ratio of about 0.3 to about 0.4.

[0068] The catalysts of this disclosure can be adapted to a wide range of heteroatom-containing silicate materials, such as nanoporous aluminosilicates, boro, or gallosilicates, which have applications in catalytic activity or separation.

[0069] Zeolites with a 3NN aluminum distribution showed improved NO production under selective catalytic reduction (SCR) conditions after the introduction of a metal such as Cu. x The transformation is observed. For example, in some embodiments, the zeolite catalysts of the present disclosure have aging durability and high or improved catalytic activity compared to zeolites that do not have a 3NN aluminum distribution.

[0070] In some embodiments, the zeolite catalyst of this disclosure, after hot water aging at 800°C, exhibits a 10% higher NO content. x The transformation is observed (in the presence of 10 volume% vapor and the remainder air, at 800°C for 16 hours, the exhaust gas under pseudo-steady state conditions for 80,000 hours). -1 (Having a volume-based space velocity of per hour, and containing a gas mixture of 500 ppm NO, 500 ppm NH3, 10% O2, 5% H2O, and the remainder N2). In some embodiments, the zeolite catalyst of this disclosure, after hydrothermal aging at 850°C (16 hours), contains at least 50% NO x Provides conversion (under the same conditions as above).

[0071] In some embodiments, the zeolite catalyst of the present disclosure having a 3NN aluminum distribution is dehydrated in an inert atmosphere of argon at ambient pressure at 125°C or 150°C using 20 μL of water per 50 mg of dehydrated catalyst. 13In batch reactions of CH3OH, it exhibits improved catalytic performance for methanol dimerization, with approximately 10% higher conversion compared to zeolites that do not contain the 3NN moiety. The conversion of methanol to dimethyl ether is insightful. 13 The results were traced by 13C NMR.

[0072] Zeolite synthesis This disclosure relates to zeolite catalysts having aging durability and improved catalytic activity. For example, the zeolite catalysts include a specific aluminum distribution, i.e., the positioning of two aluminum atoms in the zeolite structure at 3NN relative positions. The zeolite catalysts have two tetrahedral Al moieties separated by two tetrahedral Si moieties. This disclosure also covers processes and methods for characterizing and using these zeolite catalysts.

[0073] In some embodiments, the zeolite catalysts of this disclosure are prepared by various synthetic approaches. In some embodiments, the aluminum source is a precursor zeolite, such as one having a faujasite (FAU) structure. In some embodiments, the FAU source includes Na-Y or zeolite Y in various dealuminized forms. In some embodiments, other zeolite precursors may also be used. In some embodiments, the aluminum source may be an aluminum salt or complex, such as aluminum isopropoxide, aluminum sulfate, and related compounds.

[0074] In some embodiments, the disclosure further covers methods for forming zeolite catalysts. For example, the method includes forming a reaction mixture comprising at least one alumina source containing a zeolite (typically a zeolite having a FAU skeleton), at least one silica source (such as a source containing an alkali metal silicate solution and / or colloidal silica), at least one organic structure directing agent, and optionally, a secondary alkali metal cation source for increasing the alkali metal content of the reaction mixture. The reaction mixture is typically provided under alkaline aqueous conditions. In certain embodiments, the sum of the molar ratios of alkali metal to Si (M / Si, where M is the number of moles of alkali metal) and organic structure directing agent to Si (R / Si, where R is the number of moles of organic structure directing agent) is greater than the molar ratio of hydroxide ions to Si (OH / Si). In other words, the sum of the molar ratios M / Si + R / Si is greater than the molar ratio OH / Si. For bulk reaction mixtures, the SAR range is typically about 25 to about 35.

[0075] In some embodiments, the total M / Si + R / Si ratio is greater than approximately 0.75, or greater than approximately 0.80, or greater than approximately 0.82, or greater than approximately 0.85, for example, in the range of approximately 0.75 to approximately 0.95, or approximately 0.80 to approximately 0.95, or approximately 0.85 to approximately 0.95.

[0076] In some embodiments, the OH / Si molar ratio is less than about 0.7, or less than about 0.65, or less than about 0.6, or less than about 0.55, for example, in the range of about 0.3 to about 0.7, or about 0.4 to about 0.65.

[0077] In some embodiments, the individual M / Si molar ratios are at least about 0.4, or at least about 0.5, or at least about 0.6, or at least about 0.7, or at least about 0.8, for example, in the range of about 0.4 to about 1.2, or about 0.6 to about 1.0, or about 0.7 to about 0.9. Examples of alkali metals include lithium, sodium, potassium, rubidium, cesium, or francium. In certain embodiments, the alkali metal is sodium or potassium.

[0078] In some embodiments, the individual R / Si molar ratios are less than about 0.12, or less than about 0.11, or less than about 0.10, or less than about 0.08, or less than about 0.06, for example, in the range of about 0.04 to about 0.12, or about 0.06 to about 0.10.

[0079] The reaction mixture can also be characterized by the molar ratio of water to Si (H2O / Si), which is typically in the range of about 12 to about 40.

[0080] The alkali metal silicate solution used in the reaction mixture can provide all the alkali metal content necessary to achieve the above ratio. However, the alkali metal content of the reaction mixture can optionally be supplemented with a secondary alkali metal cation source, such as alkali metal sulfates (e.g., Na2SO4), alkali metal acetates (e.g., sodium acetate), and alkali metal bromides (e.g., sodium bromide). If desired, in certain embodiments, the alkali metal silicate solution can be supplemented or substituted with other silica sources such as colloidal silica, fumed silica, tetraethyl orthosilicate (TEOS), and combinations thereof.

[0081] Zeolites used as alumina sources can be diverse and may include various zeolite materials known in the art, particularly various aluminosilicate zeolites. In certain embodiments, zeolites having a FAU crystal structure formed by a 12-ring structure and having channels of about 7.4 Å are used, and examples of such zeolites include faujasite, zeolite X, zeolite Y, LZ-210, and SAPO-37. Such zeolites are characterized by a three-dimensional pore structure having pores running perpendicular to each other in the x, y, and z planes and having secondary structural units 4, 6, and 6-6. The exemplary SAR range of bulk FAU zeolite materials is about 3 to about 6, and typically the unit cell size range is 24.35 to 24.65 when determined by XRD. Zeolite Y is particularly useful for certain embodiments of the present invention. FAU zeolites are typically Na + It is used in alkali metal forms such as morphology. In some embodiments, the FAU zeolite is in sodium form and contains about 2.5% to 13% by weight of Na2O.

[0082] A typical organic structure-directing agent for this synthesis is adamantyltrimethylammonium hydroxide, but other amines and / or quaternary ammonium salts may be substituted or added. Examples include quaternary ammonium cations having substituents selected from the group consisting of alkyl, adamantyl, cyclohexyl, aromatic, and combinations thereof. Further examples of organic structure-directing agents include cyclohexyltrimethylammonium, benzyltrimethylammonium, and dimethylpiperidinium hydroxide.

[0083] Hydroxide ions are the only necessary mineralizer required in the reaction mixture, and the amount of hydroxide needed to achieve the above ratio can be supplied exclusively from alkali metal silicate solutions, and to a lesser extent, from organic structure-directing agent sources. If desired, the hydroxide ion content can be supplemented with additional hydroxide ion sources such as NaOH or KOH.

[0084] The reaction mixture can be characterized with respect to its solids content, expressed as the weight percentage of silica (SiO2) and alumina (Al2O3). The solids content can vary, with exemplary ranges being about 5 to about 25%, or about 8 to about 20%.

[0085] The reaction mixture is heated in a pressure vessel with stirring to produce the desired CHA crystalline product. Typical reaction temperatures are in the range of about 100°C to 180°C, for example, about 120°C to 160°C, with corresponding spontaneous pressures. Typical reaction times are about 30 hours to 3 days. Optionally, the product may be centrifuged. Organic additives may be used to assist in the handling and isolation of the solid product. Spray drying is an optional step in the processing of the product.

[0086] In some embodiments, zeolites having an MOR crystal skeleton are formed as intermediate products or by-products. The MOR phase may contain an organic template.

[0087] Solid zeolite products are heat-treated or calcined in air or nitrogen. Typical calcination temperatures are approximately 400°C to 850°C (e.g., approximately 500°C to 700°C) and last for 1 to 10 hours. Following the initial calcination, the CHA zeolite product is mainly converted into alkali metal forms (e.g., Na). + (Form) is used. Optionally, one or more ammonia ion exchanges are used to exchange NH4 zeolites. + It is possible to create a shape, and optionally, further firing, H + To form a shape.

[0088] In some embodiments, the CHA zeolite is further ion-exchanged with a co-catalyst metal to form a metal-promoting zeolite catalyst. For example, copper or iron can be ion-exchanged to form Cu-CHA or Fe-CHA. When copper acetate is used, the copper concentration of the liquid copper solution used for copper ion exchange is in the range of about 0.01 to about 0.4 moles in some embodiments, and more specifically, in the range of about 0.05 to about 0.3 moles.

[0089] In some embodiments, the CHA zeolite crystals obtained from crystallization may be about 80% to about 99% crystalline or about 90% to about 97% crystalline.

[0090] In some embodiments, the CHA zeolite product may be characterized by a relatively low mesopore surface area (MSA) combined with a zeolite surface area (ZSA) that provides good catalytic performance. In some embodiments, the MSA of the CHA zeolite product is approximately 25 m 2 Less than / g or approximately 10m 2 Less than / g (for example, approximately 5 to approximately 25mg) 2 The ZSA of CHA zeolite products is typically at least about 400 m 2 / g, or at least about 450m 2 / g, or at least about 500m 2 The value is / g, and the exemplary ZSA range is approximately 400 to 600m. 2 / g or approximately 450-600m 2The value is / g. Pore volume and surface area characteristics can be determined by nitrogen adsorption (BET surface area method). Mesopore and zeolite (micropore) surface areas were determined by N2 adsorption porosimetry on a Micromeritics TriStar 3000 series instrument according to the ISO 9277 method. The samples were degassed for a total of 6 hours on a Micromeritics SmartPrep degasser (heated to 300°C over 2 hours under a stream of dry nitrogen, then held at 300°C for 4 hours). The nitrogen BET surface area is determined using five partial pressure points from 0.08 to 0.20. The surface areas of the zeolite and matrix are determined using the same five partial pressure points and calculated using Harkins and Jurat plots. Pores with a diameter greater than 20 Å are considered to contribute to the matrix surface area.

[0091] CHA zeolite products also include, for example, H + Zeolite materials of a certain morphology may be characterized by a relatively low normalized ZSA loss after treatment with NH4F solution, such as less than 60% (or less than 50%), by stirring at 350 rpm and sonicating (35 kHz, 90 W) at 50°C for 20 minutes, followed by drying and calcination at 450°C for 6 hours. The formula for calculating the normalized ZSA loss is presented in U.S. Patent No. 11,267,717.

[0092] In some embodiments, the CHA zeolite product is typically measured using diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy at 3742 cm⁻¹. -1 The integrated intensity of the peak (peak X) centered at 3609 cm² -1As can be estimated by comparing the integrated intensity of the peak (peak Y) centered on , it may exhibit relatively less surface silanol compared to the cross-linked silanol (Brønsted moiety). DRIFTS measurements were performed in a Thermo Nicolet with a mercury-cadmium-telluride (MCT) detector and a Harrick environment chamber with a ZnSe window. The sample was ground into a fine powder using a mortar and pestle and then packed into a sample cup. The sample powder was first dehydrated at 400°C for 1 hour while flowing Ar at a flow rate of 40 ml / min, and then cooled to 30°C. Spectra were taken for the sample, and KBr was used as the reference. In certain embodiments, the surface silanol ratio (X / Y peak ratio) of the CHA zeolite product is less than about 0.04 or less than about 0.03.

[0093] The CHA zeolite products obtained by this method typically have an average crystal size ranging from approximately 3 μm to a maximum of approximately 200 nm to approximately 3 μm, or from approximately 500 nm to approximately 2 μm, or from approximately 800 nm to approximately 1.5 μm. The average crystal size can be measured, for example, using microscopy, such as scanning electron microscopy (SEM).

[0094] CHA zeolite products also 27 H is determined as the percentage of total aluminum detected by Al NMR. + The morphology can be characterized by the amount of extra-framework aluminum (EFAl). + The form is Na + The morphology is obtained by ammonium exchange with NH4NO3, followed by calcination at 450°C (6 hours). In certain embodiments, the CHA zeolite product has less than about 20% or less than about 18%, for example, about 5% to about 18% (or about 5% to about 15%) of EFAl. The percentage of extraskeletal aluminum (EFAl) is defined as the integrated peak intensity in the frequency range of 20 to -30 ppm in the NMR spectrum measured at 14.1 T.

[0095] Determination of zeolite catalysts containing a third nearest neighbor (3NN) pair of aluminum atoms. A method for characterizing the covalent bonding between J-bonded heteroatoms in zeolite materials involves synthesizing the zeolite material, with trimethyladamantylammonium hydroxide (TMAdaOH) used as an organic structure directing agent (OSDA) for the zeolite material. Zeolite crystallization can be carried out using a mineralizer, a Na+ source, an Al source, and / or a Si source. The mineralizer may be sodium hydroxide (NaOH). The Na+ source can be selected from NaOH and / or Na2SO4. The Al source can be selected from Na-FAU and / or aluminum isopropoxide. The Si source can be selected from colloidal silica and / or a sodium silicate solution. The zeolite material product is then isolated via filtration, dried, and calcined at 540°C for 6 hours to produce the Na+ form. The zeolite material is characterized via XRD and N2-physicoadsorption. After calcination, one or more NH4 until the Na2O content reaches <500 ppm. + The replacement will be carried out. Next, the NH4 zeolite material + The shape is baked at 450°C for 6 hours, H + The morphology is induced, and then analyzed by solid-phase NMR.

[0096] The distribution of Al species within the zeolite skeleton, including paired 2NN and 3NN Al species, is 2D 27 Al 29 Si}J-HMQC NMR and 2D 29 Si{ 29 This can be evaluated by Si}J-mediated SQ-DQ NMR spectroscopy, and both types were acquired at 9.4T, 8kHz MAS, and 100K.

[0097] Correlating NMR spectra to the aluminum (Al) sites of zeolite materials is carried out by analyzing both 1D and 2D solid-state NMR spectra. From the 1D solid-state 1D NMR of zeolite, 29 the Si NMR spectra exhibit Si signals in the Q 4 regions of -105 ppm, -110 ppm, -113 ppm, -115 ppm, and -119 ppm. Bridged Si silanol species give rise to Si signals in the Q 29 regions of -97 ppm, -99 ppm, and -101 ppm. In the 2D 3 Al{ 29 Si} J-mediated spectra, the correlated 27 Al- 29 Si signals are assigned based on previous 2D 27 Si{ 29 Si} and 29 Si{ 29 Si} and 29 Si{ 1 H} NMR analyses of calcined zeolites, analysis of the average T-O-T bond angle and T-O bond length, and 29 Si chemical shift values, as well as comparison with previous literature. The correlated 27 Al and 29 Si signals are resolved at Si shifts of -107 ppm to -105 ppm and -101 to -99 ppm in the 2D 27 Al{ 29 Si} J-mediated HMQC spectra. This correlation can also be calculated by correlating the Q 29 (1Al) 4 Si chemical shift δ to the average T-O-T bond angle θ'. 29 A method for characterizing the covalent connectivity between J-coupled heteroatoms in a zeolite material, wherein the synthesis in the zeolite material comprises using trimethyladamantylammonium hydroxide (TMAdaOH) as an organic structure-directing agent (OSDA). This synthesis further includes crystallizing a silicate solution and Na-FAU and neutralizing the excess with H2SO4.

[0098] Si-O- 29 Si-O-29 Examples of the correlation between differences in Si bonding properties and 2D NMR spectra are shown in Figures 7(A) and 7(B).

[0099] A method for characterizing the covalent bonding between J-bonding nuclei of heteroatoms in a zeolite material, wherein the NMR spectrum is a 2D solid-phase NMR spectrum.

[0100] A method for characterizing the covalent bonding between J-bonding nuclei of heteroatoms in a zeolite material, wherein the NMR spectrum is an HQMC NMR spectrum.

[0101] A method for characterizing the covalent bonding between J-bonding nuclei of heteroatoms in a zeolite material, wherein the zeolite material comprises a zeolite composition having paired aluminum atoms in its framework, the paired aluminum atoms being separated as neighboring atoms of a second or third nearest neighbor T site in the zeolite structure.

[0102] A method for characterizing the covalent bonding between J-bonding nuclei of heteroatoms in a zeolite material, wherein the zeolite catalyst is a chabazite zeolite catalyst.

[0103] A method for characterizing the covalent bonding between J-bonding nuclei of heteroatoms in a zeolite material, wherein a chabazite zeolite catalyst is synthesized using Na-FAU.

[0104] A method for characterizing the covalent bonding between J-bonding nuclei of heteroatoms in a CHA zeolite material, wherein the catalyst composition is 2D 29 Si{ 29 A method having signatures in the range of -104 ppm to -108 ppm in the single quantum (SQ) dimension and -208 to -212 ppm in the double quantum (DQ) dimension when measured using Si}J-mediated NMR and 2D.

[0105] A method for characterizing the covalent connectivity between J-bonded nuclei of heteroatoms in a CHA zeolite material, the method comprising a catalyst composition that gives an NMR spectral signature with peak intensities that are about 10% to 50% higher than those of a catalyst composition in which paired aluminum atoms are not third nearest neighbors (3NN).

[0106] A method for characterizing the covalent connectivity between J-bonded nuclei of heteroatoms in a CHA zeolite material, the catalyst composition giving 27 Al{ 29 when measured using 2D 29 Al{ 27 Si}J-HMQC NMR, an NMR spectral signature in the Si dimension in the range of -98 ppm to -100 ppm and in the Al dimension in the range of 55 to 59 ppm.

[0107] Embodiments Without limitation, some embodiments of the present disclosure include the following.

[0108] Embodiment 1. A zeolite catalyst having paired aluminum atoms, the paired aluminum atoms being third nearest neighbors (3NN) in the zeolite structure, the zeolite catalyst having aging durability, improved catalytic activity, or a combination thereof.

[0109] Embodiment 2. The zeolite catalyst according to Embodiment 1, wherein the zeolite catalyst is a CHA zeolite catalyst.

[0110] Embodiment 3. The zeolite catalyst according to Embodiment 2, wherein the CHA zeolite catalyst is a copper-CHA catalyst.

[0111] Embodiment 4. The catalyst composition according to Embodiment 1, wherein the zeolite is a small pore zeolite.

[0112] Embodiment 5. The catalyst composition according to Embodiment 4, wherein the small pore zeolite is AEI.

[0113] Embodiment 6. The catalyst composition according to Embodiment 4, wherein the small-pore zeolite is AFX.

[0114] Embodiment 7. The catalyst composition according to Embodiment 4, wherein the small-pore zeolite is an AFT.

[0115] Embodiment 8. The zeolite catalyst is 2D 29 Si{ 29 When measured using S}iJ-mediated NMR, the range is -104 ppm to -108 ppm in the single quantum (SQ) dimension and -208 to -212 ppm in the double quantum (DQ) dimension. 29 A zeolite catalyst according to Embodiment 1, having a Si NMR signature.

[0116] Embodiment 9. The zeolite catalyst is 2D 27 Al 29 When measured using Si}J-HMQC NMR, 29 In the Si dimension, -98 ppm to -100 ppm and 27 The zeolite catalyst according to Embodiment 1, having an NMR signature in the Al dimension in the range of 55 to 59 ppm.

[0117] Embodiment 10. Aging durability after 800°C hot water aging, and the zeolite catalyst exhibits 10% higher NO than zeolites that do not contain 3NN moieties. x A zeolite catalyst according to Embodiment 1 that exhibits a transformation.

[0118] Embodiment 11. Age durability is after 850°C hot water aging, and the zeolite catalyst contains at least 50% NO x A zeolite catalyst according to Embodiment 1 that exhibits a transformation.

[0119] Embodiment 12. The zeolite catalyst according to Embodiment 1, wherein the improved catalytic activity of the zeolite catalyst for methanol dimerization is approximately 10% higher than that of a zeolite that does not contain the 3NN moiety.

[0120] Embodiment 13. The zeolite catalyst according to Embodiment 1, wherein the zeolite catalyst has an SiO2 / Al2O3 ratio (SAR) selected from 8-40, 10-30, and 11-25.

[0121] Embodiment 14. The zeolite catalyst according to Embodiment 1, wherein the zeolite catalyst further comprises copper (Cu) having a Cu content corresponding to a Cu / Al ratio selected from 0.2 to 0.5, 0.25 to 0.45, and 0.3 to 0.4.

[0122] Embodiment 15. A catalyst article effective for reducing nitrogen oxides (NOx) from lean-burn engine exhaust gas, comprising a substrate carrier having the selective catalytic reduction (SCR) catalyst described in Embodiment 1.

[0123] Embodiment 16. The catalyst article according to Embodiment 15, wherein the substrate carrier is a honeycomb substrate and is optionally composed of a metal or ceramic.

[0124] Embodiment 17. The catalyst article according to Embodiment 15, wherein the honeycomb substrate carrier is a flow-through substrate or a wall-flow filter.

[0125] Embodiment 18. Exhaust gas treatment system, A lean-burn engine that generates exhaust flow, An exhaust gas treatment system comprising a catalytic article according to Embodiment 15, which is positioned downstream of a lean-burn engine and is in fluid communication with the exhaust gas flow.

[0126] Embodiment 19. The following: a. Diesel oxidation catalyst (DOC) positioned upstream of the catalytic article, b. A soot filter positioned upstream of the catalyst article. and c. An exhaust gas treatment system according to Embodiment 18, further comprising one or more ammonia oxidation catalysts (AMOX) positioned downstream of a catalytic article.

[0127] Embodiment 20. A process for preparing a selective catalytic reduction (SCR) catalyst, (a) Prepare the catalyst described in any one of Embodiments 1 to 14, (b) Applying the catalyst as a coating on a ceramic or metal honeycomb substrate monolith, (d) Drying the coated monolith, (e) A process comprising firing the coated monolith at a temperature in the range of 400°C to 800°C.

[0128] Embodiment 21. The zeolite catalyst according to Embodiment 1, wherein the aluminum source is Na-FAU.

[0129] Embodiment 22. The zeolite catalyst according to Embodiment 1, wherein the aluminum source is aluminum isopropoxide.

[0130] Embodiment 23. The zeolite catalyst according to Embodiment 1, wherein the aluminum source is H-FAU.

[0131] Embodiment 24. The zeolite catalyst according to Embodiment 1, wherein the silicon source is sodium silicate.

[0132] Embodiment 25. The zeolite catalyst according to Embodiment 1, wherein the silicon source is colloidal silica.

[0133] Embodiment 26. The zeolite catalyst according to Embodiment 1, wherein the silicon source is H-FAU.

[0134] Embodiment 27. The zeolite catalyst according to Embodiment 1, wherein the Na / Si ratio is 0.818.

[0135] Embodiment 28. The zeolite catalyst according to Embodiment 1, wherein the Na / Si ratio is 0.785.

[0136] Embodiment 29. The zeolite catalyst according to Embodiment 1, wherein the Na / Si ratio is 0.194.

[0137] Embodiment 30. The zeolite catalyst according to Embodiment 1, wherein the OH / Si ratio is 0.506.

[0138] Embodiment 31. The zeolite catalyst according to Embodiment 1, wherein the OH / Si ratio is 0.675.

[0139] Embodiment 31. The zeolite catalyst according to Embodiment 1, wherein the OH / Si ratio is 0.418.

[0140] Claims or descriptions that include “or” or “and / or” between at least one member of a group are considered satisfied if one, more than one, or all members of a group are present in, employed in, or otherwise related to a given product or process, unless otherwise evident from the context. This disclosure includes embodiments in which exactly one member of a group is present in, employed in, or otherwise related to a given product or process. This disclosure includes embodiments in which more than one or all of the members of a group are present in, used in, or otherwise related to a given product or process.

[0141] Furthermore, this disclosure encompasses all variations, combinations, and substitutions in which at least one limitation, element, clause, and descriptive term from at least one of the enumerated claims is introduced into another claim. For example, any claim dependent on another claim may be modified to include at least one limitation found in any other claim dependent on the same basic claim. Where elements are presented as a list, for example in Markush group form, each subgroup of the elements is also disclosed, and any element may be removed from the group. In general, where this disclosure or aspects thereof are referred to as containing certain elements and / or features, it should be understood that embodiments of this disclosure or aspects thereof consist of or are essentially such elements and / or features. For brevity, these embodiments are not described so specifically in this specification. Where a scope is given (e.g., [X] to [Y]), unless otherwise indicated, it includes the endpoints (e.g., [X] and [Y] in the phrase "[X] to [Y]"). Furthermore, unless otherwise indicated, or unless it is evident from the context and the understanding of those skilled in the art, values ​​expressed as ranges may, unless the context explicitly indicates otherwise, assume any specific value or subrange within the ranges described in different embodiments of this disclosure, up to one-tenth of the lower limit unit of the range.

[0142] Those skilled in the art will recognize, or can verify by routine experimentation, many equivalents to the specific embodiments of this disclosure described herein. Such equivalents are intended to be covered by the following claims. [Examples]

[0143] The following examples are illustrative and not intended to limit the scope of the disclosure.

[0144] Example 1: Measurement of catalytic properties of samples A, B, C, D, and G Sample A is a CHA zeolite synthesized using trimethyladamantylammonium hydroxide (TMAdaOH) as an organic structure-directing agent (OSDA) for CHA. For the crystallization of Sample A, sodium silicate solution (SiO2 / Na2O=2.6, solid content 37%) and Na-FAU (SiO2 / Al2O3=5.1) were used as the Si and Al sources, respectively. The desired OH / Si ratio was obtained by neutralizing the excess OH with H2SO4. Regarding the sodium silicate solution, Na + Assuming a 1:1 ratio of OH to SiO2, the OH / SiO2 ratio was calculated.

[0145] Furthermore, sample B, which is a CHA zeolite, was synthesized, and trimethyladamantylammonium hydroxide (TMAdaOH) was used as an organic structure directing agent (OSDA) for CHA. For the crystallization of sample B, sodium hydroxide (NaOH) was used as a mineralizing agent and in the gel. + It was used as the sole source, and aluminum isopropoxide and colloidal silica (40 wt% SiO2) were used as Si and Al sources, respectively.

[0146] After crystallization, samples A and B were isolated by filtration, dried, and calcined at 540°C for 6 hours to produce the Na+ form.

[0147] After calcination, one or more NH4 until the Na2O content reaches <500 ppm. + The replacement was carried out. NH4 + The shape is further baked at 450°C for 6 hours, H + It gave rise to form.

[0148] NMR is used to determine the conversion of methanol to dimethyl ether over time. In some embodiments, insights 13 Using 13C NMR in a batch reactor, the conversion of methanol to dimethyl ether at 125°C and 150°C was used to dehydrate samples A and B. + The catalytic properties of the morphology were measured. As shown in Figure 1A, a typical time-resolved model was obtained. 13The 13C direct excitation NMR spectrum is in the range of 47 ppm to 54 ppm. 13 The C signal is shown, which corresponds to adsorbed methanol species in different local environments. The spectra were obtained at 11.7 T and 5 kHz MAS. Figure 1A also shows 13 The NMR spectrum also shows a 1C signal in the range of 56 ppm to 64 ppm, corresponding to the dimethyl ether species.

[0149] The methanol conversion as a function of time is shown in Figure 1B for the reactions across both samples at 125°C and 150°C. To determine the methanol conversion over time under different conditions, the spectral intensities for the adsorbed methanol and dimethyl ether species were integrated, respectively. At both temperatures, the methanol conversion rate for sample A was significantly higher than that for sample B.

[0150] Samples C, D, and G are CHA zeolites synthesized using trimethyladamantylammonium hydroxide (TMAdaOH) as an organic structure-directing agent (OSDA) for CHA. The Si and Al sources for sample C were sodium silicate and Na-FAU, respectively. The molar ratios of the components in sample C are as follows: Na / Si = 0.785, R / Si = 0.03, OH / Si = 0.625, and H2O / Si = 33.2. Crystallization of sample C was carried out at 140°C for 72 hours.

[0151] The Si and Al sources for sample D were colloidal silica and aluminum isopropoxide, respectively. The molar ratios of the components in sample D were as follows: Na / Si = 0.207, R / Si = 0.108, OH / Si = 0.315, and H2O / Si = 23.6. Crystallization of sample D was carried out at 160°C for 45 hours.

[0152] The Si and Al sources for sample G were H-FAU. The molar ratios of the components of sample G were as follows: Na / Si = 0.194, K / Si = 0.124, R / Si = 0.100, OH / Si = 0.418, and H2O / Si = 22.2. Crystallization of sample G was carried out at 150°C for 24 hours.

[0153] Samples C, D, and G were calcined at 540°C for 6 hours under a flow of dry air. After the first calcination step, unlike samples A and B, samples C, D, and G were subjected to two ammonium exchange steps. Subsequently, following the two ammonium exchange steps, a second calcination step was performed at 450°C for 6 hours under a flow of dry air. Cu ions were converted to H + The target CuO filling content of 6.8–7.2% by weight was achieved by introducing the material into a morphological zeolite. A catalyst coating containing Cu-CHA, zirconium oxide, and a pseudo-boehmite binder was applied to the sample via a wash-coat process. The coated monolith was dried at 110–150°C and calcined at approximately 550°C for 1 hour. The coating process was performed at a rate of 2.2 g / in 3 The catalyst packing was provided, of which 5% was zirconium oxide and 5% was an aluminum oxide binder. The coated monolith was hydro-aged at 800°C for 16 hours in the presence of 10% H2O / air.

[0154] NO (Nox) from monoliths (samples C, D, and G) aged at 800°C for 16 hours. x The conversion was performed over 80,000 hours under pseudo-steady-state conditions in a gas mixture of 500 ppm NO, 525 ppm NH3, 10% O2, 10% H2O, and the remainder N2, with a temperature gradient of 5°C / min from 200°C to 550°C. -1 The gas volume-based space velocity was measured in a laboratory reactor. NO levels are shown in Figures 1C and 1D, respectively. x The conversion and N2O selectivity data demonstrate that these performance characteristics of interest directly depend on the amount of 3NN paired Al moieties in the three samples. NO for samples A and B x The conversion has been previously determined in U.S. Patent No. 11,267,717 (as samples F and C in Figure 5) and is shown in Figure 1E.

[0155] Sample G, which exhibits significantly higher 3NN paired Al moieties than both Sample C and Sample D, has the highest NOx across the entire temperature range. xIt exhibits conversion and has the lowest N2O selectivity of the three samples across the entire temperature range. Sample D, which shows the lowest third nearest neighbor Al site configuration among the three samples, has the lowest NO content among the three materials except at 550°C. x It has a conversion property and exhibits the highest N2O selectivity across the entire temperature range.

[0156] Samples A, B, C, D, and G can be divided into two main groups. Sample A was synthesized using silicate solution and Na-FAU as Si and Al sources, respectively, while Sample B was synthesized using colloidal silica and aluminum isopropoxide. Both Samples A and B underwent ion exchange once with ammonium. Samples C and D had the same starting materials as Samples A and B, respectively. Sample G was synthesized using H-FAU as silicon and aluminum sources. Samples C, D, and G underwent ion exchange twice with ammonium. Of Samples A and B, Sample A showed better performance, as demonstrated in the methanol conversion tests in Figures 1A and 1B. Of Samples C, D, and G, Samples C and G showed better performance, as shown in Figures 1C and 1D, x In conversion and N2O selectivity tests, higher 3NN paired Al moieties and better performance were observed. Figures 1A to 1E show that among samples A, B, C, D, and G, samples A, C, and G exhibit the catalytic performance and unique NMR characteristics according to this disclosure. The following table (Table 1) shows data for samples A, C, and G, their starting materials, and their Na / Si and OH / Si ratios.

[0157] [Table 1]

[0158] Example 2: Measurement of reaction characteristics via solid-phase NMR Solid-phase NMR in aluminosilicate zeolite 27 Al and 29It is sensitive to the local chemical environment of the Si atoms and can be used to determine reaction characteristics. In some embodiments, Figure 2A shows H of sample A and sample B having approximately the same SiO2 / Al2O3 ratio (SAR). + One-dimensional (1D) form 29 The direct Si excitation NMR spectra are shown. The spectra were obtained at 18.8 T, 20 kHz MAS and 298 K. Each sample was analyzed at -111 ppm and -105 ppm, Q - (0Al) and Q 4 It exhibits two strong signals corresponding to the (1Al) portion. Q 4 The relative signal intensities for (0Al) and Q4(1Al) are similar for both sample A and sample B, which corresponds to samples A and B having similar SAR values.

[0159] Figure 2B shows the H of sample A and sample B. + 1D form 27 The direct excitation NMR spectra of Al are shown. The significant difference in both spectra at 59 ppm is evident. 27 The Al signal corresponds to 4-coordinate Al atoms. This is consistent with their incorporation into the aluminosilicate zeolite framework, but the weak signal around -1 ppm in each spectrum corresponds to 6-coordinate Al atoms outside the framework. These 1D of the two samples 27 No significant differences were observed in the Al NMR spectra.

[0160] Example 3: Measurement of reaction characteristics via multidimensional NMR technology By using multidimensional NMR to investigate nanoscale through-bond and through-space interactions between NMR-active nuclei, we provided more detailed insights into the local chemical environment of materials. For example, in aluminosilicate materials... 29 Si-O- 29 To detect Si bonding, two-dimensional (2D) J-mediated 29 Si{ 29 Si single-quantum (SQ)-double-quantum (DQ) NMR correlation spectra can be used.

[0161] In some embodiments, Figures 3A and 3B show H of sample A and sample B. + 2D form 29 Si{ 29 The Si}J-mediated SQ-DQ NMR correlation spectra are shown. In these spectra, the correlation signal intensity is: 29 Si-O- 29 Covalent bonds, including those mediated by covalently bridging oxygen atoms in the Si portion 29 Si atoms can be clearly identified. The signal along the diagonal indicates the same local environment. 29 Si-O- 29 Corresponding to the Si portion, pairs of correlated signals having the same double quantum shift (vertical dimension) that are equidistant on both sides of the diagonal are two different local 29 Si environment 29 Si-O- 29 This corresponds to the Si portion. For example, at -112 ppm in the single quantum (horizontal) dimension and -224 ppm in the double quantum (vertical) dimension in each spectrum. 29 The Si signals correspond to the covalently bonded Q4(0Al) portion in the siliceous region of each material. In comparison, the correlation signals at -216 ppm in the SQ (vertical) dimension and at -105 ppm and -111 ppm in the DQ (horizontal) dimension in the spectrum obtained from sample A correspond to the covalently bonded Q4(0Al) and Q4(1Al) portions. Notably, the correlation signal near the diagonal at -209 ppm in the vertical dimension appears in the spectrum obtained from sample A but is not detected in the spectrum obtained from sample B. These signals correspond to the covalently bonded Q4(1Al) portion present in the Al framework of the Al-O-(Si-O)2-Al configuration.

[0162] Example 4: Measurement of covalent bond connectivity via solid-phase / heteronuclear multiple quantum coherence (HQMC) NMR Similarly, solid-phase 2D NMR technology is also used in aluminosilicate materials. 27 Al and 29It can be used to detect covalent bonding between J-bonded heteroatoms such as Si. 27 Al 29 The Si}J-mediated heteronuclear multiple quantum coherence (HMQC) NMR spectrum shows the skeleton in aluminosilicate zeolite. 27 This can provide direct information about the Al atom. 27 Al-O- 29 Different types and distributions of the Si portion can be distinguished.

[0163] In one embodiment, Figures 4A and 4B show H of sample A and sample B. + 2D data obtained regarding morphology 27 Al 29 The Si}J-HMQC NMR spectra are shown. The spectra were obtained at 9.4T, 8kHz MAS, and 100K. These spectra show the skeleton 29 At 57 ppm, corresponding to the Al atom in the 4-coordinate framework correlated with the Si atom. 27 The Al signal is revealed in the spectra obtained from both samples. 27 The Al signal corresponds to the Q4(1Al) portion at -106 ppm. 29 It correlates with the Si signal. The spectrum of sample A is at 57 ppm from the Al atoms in the skeleton. 27 Al signal and Q 4 (2Al) Belongs to the species 29 This indicates that a further correlation signal intensity is observed between the signal at -99 ppm in the Si dimension. This signal is not observed in the spectrum obtained from sample B, indicating that such a portion is largely absent. This provides further evidence that sample A contains more locally paired Al atoms separated by one or two O-Si-O moieties than sample B. The different distribution of skeletal Al atoms in samples A and B, including the types and number of adjacent skeletal Al atoms, is thought to explain their different adsorption and reaction properties.

[0164] Example 5 To further demonstrate the spectroscopic signature of Al forming the third nearest neighbor (3NN) pair, a 2D sample of the third sample, called sample C, was prepared. 29 Si{ 29 The Si}J-mediated solid-phase single-quantum and double-quantum NMR correlation spectra are shown in Figure 8. J coupling occurs between NMR-active nuclei in covalently bonded atoms or by other covalently bonded atoms. Sample C has 11 SARs, in contrast to approximately 19 SARs of samples A and B. The synthesis of sample C is similar to that of sample A. 2D in Figure 8 29 Si{ 29 The Si}J-mediated SQ-DQ NMR correlation spectra show their isotropy. 29 Based on the Si chemical shift, 29 The signals from the J bond pair in the Si nucleus are resolved. These were obtained under the same conditions as for samples A and B. The correlation signals at -112 ppm in the single quantum (SQ) dimension and -224 ppm in the double quantum (DQ) dimension are covalently bonded by the bridging oxygen atom. 4 (0Al) pairs of types (for example, 29 Si-O- 29 Corresponding to Si), on the other hand, the signals at -216 ppm in the dual quantum dimension and at -105 and -111 ppm in the single quantum dimension are similarly covalently bonded by bridging oxygen atoms Q 4 (1Al) and Q 4 Corresponds to the (0Al) species. Most importantly, the correlation (SQ, DQ) strength at (-104 ppm, -208 ppm) is the same as the paired Q 4 This corresponds to the (1Al) species, which provides direct evidence of a third nearest-neighbor aluminum arrangement.

[0165] Example 6 In addition to investigating covalent connectivity using J-coupling, solid-phase NMR can be used to determine their isotropy. 29 Based on the Si chemical shift, 29 Through space used to decompose signals from dipole coupling pairs of Si nuclei 29 Si- 29By utilizing Si dipole-dipole coupling, the proximity of nuclei at greater distances (approximately 1 nm) can be investigated. Figures 9(A) and 9(B) show 2D for two samples with 11 SARs, sample C and sample D, respectively. 29 Si{ 29 The Si dipole-mediated NMR correlation spectra are shown, which clearly indicate different intensity distributions representing different Al distributions within the zeolite framework. The synthesis of sample D is similar to that of sample B. These measurements are the same as those described above for 2D 29 Si{ 29 The same conditions were used for the Si}J-mediated correlation spectrum. The regions of correlation signal intensity were separated by approximately 1 nm. 29 This corresponds to the nearest pairs of Si nuclei (and their associated atoms). The signals at -112 ppm in a single quantum dimension and approximately -223 ppm in a double quantum dimension correspond to the nearest Q 4 Corresponds to the (0Al) species. The signals at -105 ppm and approximately -111 ppm in the single quantum dimension correlate with the signal at -216 ppm in the double quantum dimension, and the nearest Q 4 (0Al) and Q 4 Corresponds to the (1Al) species. A signal centered at -105 ppm in single quantum dimensions and at -210 ppm in double quantum dimensions is Q 4 Corresponds to adjacent pairs of (1Al) species. Both samples C and D correspond to adjacent Q 4 (1Al) 2D from the skeletal part 29 Si{ 29 Although they exhibit Si intensity, interestingly, their intensity distributions are different. For example, along the bidiagonal of the two spectra, 2D 29 Si{ 29 The Si intensity distribution appears narrower and more elongated in sample C compared to sample D, which appears more non-uniformly spread. This indicates that the skeletal Al environment in sample C is more locally uniform than the skeletal AI environment in sample D.

[0166] Example 7 To understand the differences in the spectral signatures of third nearest neighbor (3NN) type paired Al species in chabazite materials prepared using different methods, 2D 29Si{ 29 The Si}J-mediated SQ-DQ solid-state NMR correlation spectrum is shown in Figure 10. Sample D has the same silicon-to-aluminum ratio (SAR) of 11 as sample C. The spectrum shown in Figure 10 is J-bonded. 29 Decompose the signal from the Si nucleus pair and bridge oxygen atom ( 29 Si-O- 29 Covalently bonded via Si) 29 This yields a signal from pairs of Si atoms. This spectrum was obtained under the same conditions as samples A, B, C, D, and G. Correlated single quantum (SQ) at -112 ppm. 29 Si signal and double quantum (DQ) at -224 ppm 29 The Si signal is from the bridging oxygen atom ( 29 Si-O- 29 Q in the local silicate region covalently bonded by Si 4 (0Al) 29 Corresponds to pairs of Si species at -111 and -105 ppm in SQ dimension 29 DQ at -216 correlates with the Si signal. 29 The Si signal is J bond Q 4 (0Al) and Q 4 (1Al) 29 Corresponds to through-bond pairs in the Si portion. SQ at -104 ppm 29 DQ at -210 ppm correlated with Si signal 29 The Si signal is J-coupled 29 Q of the Si nucleus 4 (1Al)-OQ 4 (1Al) corresponds to the 3NN pair of Al atoms in the zeolite framework (i.e., - 27 Al-O- 29 Si-O- 29 Si-O- 27 This provides evidence of the Al-m portion. Notably, this signal appears to be less intense than the same signal from sample C in Example 5, suggesting that sample D has fewer third nearest nearest tetrahedron (T portion) configurations than sample C.

[0167] Example 8 For further comparison, a third low-SAR chabazite material, sample G, was prepared and analyzed. Sample G, like samples C and D, has an SAR of approximately 11. Figure 11 shows the 2D of sample G. 29 Si{ 29 The Si}J-mediated SQ-DQ solid-phase NMR correlation spectrum is shown. This spectrum was obtained under the same conditions as similar spectra for samples A, B, C, D, and G. 2D 29 Si{ 29 The Si}J-mediated SQ-DQ solid-phase NMR correlation spectrum is, 29 Si-O- 29 Supports Si covalent linkage mechanism 29 Figure 11 shows the correlation signal arising from the J bond pair in the Si nucleus. Figure 11 shows the single quantum (SQ) signal at -112 ppm. 29 Si signal and double quantum (DQ) at -224 ppm 29 This shows the correlation strength with the Si signal, which is Q 4 Corresponds to covalent pairs of the (0Al) species. SQ at -105 and -111 ppm. 29 DQ at -216 ppm correlates with Si signal 29 The Si signal, like other samples, is Q 4 (0Al)-OQ 4 (1Al) Compatible with linkage mechanisms. Most notably, DQ at -210 ppm. 29 The Si signal is SQ at -105 ppm. 29 Correlating with the Si signal, this is a covalently bonded Q with an aluminum arrangement forming a third nearest neighbor pair. 4 (1Al)-OQ 4 (1Al) corresponds to pairs of skeletal parts. Notably, this correlation 29 Si{ 29 The Si signal is much stronger than the intensity observed in this spectral region for samples A, B, C, and D (see above), indicating a greater number of 3NN paired Al configurations in sample G than in these other samples. In addition, the wider range of correlation intensities around (-210 ppm, -105 ppm) in Figure 11 indicates a broader distribution of different 3NN paired Al configurations present in sample G compared to the other samples.

Claims

1. A zeolite catalyst having a pair of aluminum atoms, The aforementioned zeolite catalyst is derived from H-FAU with both Al and Si sources. The pair of aluminum atoms is the third nearest neighbor (3NN) in the zeolite structure, and the zeolite catalyst has aging durability, improved catalytic activity, or a combination thereof. The zeolite catalyst is a CHA zeolite catalyst, and The zeolite catalyst is 2D ２９ Si { ２９ When measured using Si-J mediated SQ-DQ NMR, the range is -104 ppm to -108 ppm in the single quantum (SQ) dimension and -208 to -212 ppm in the double quantum (DQ) dimension. ２９ Having a Si NMR signature, Zeolite catalyst.

2. The zeolite catalyst according to claim 1, wherein the CHA zeolite catalyst is a copper-CHA catalyst.

3. The zeolite catalyst is 2D ２７ Al ２９ When measured using Si}J-HMQC NMR, ２９ In the Si dimension, -98 ppm to -100 ppm and ２７ The zeolite catalyst according to claim 1 or 2, having an NMR signature in the Al dimension in the range of 55 to 60 ppm.

4. The zeolite catalyst according to claim 1, wherein the aging durability is after hot water aging at 800°C, and the zeolite catalyst exhibits a 10% higher NOx conversion compared to a zeolite that does not contain 3NN moieties.

5. The zeolite catalyst according to claim 1, wherein the aging durability is after hot water aging at 850°C, and the zeolite catalyst exhibits at least 50% NOx conversion.

6. The zeolite catalyst according to claim 1, wherein the improved catalytic activity of the zeolite catalyst for methanol dimerization has a conversion rate approximately 10% higher than that of a zeolite that does not contain a 3NN moiety.

7. The zeolite catalyst has a SiO ２ / Al ２ O ３ ratio (SAR) selected from 8 to 40, 10 to 30, and 11 to 25. The zeolite catalyst according to claim 1.

8. The zeolite catalyst according to claim 1, wherein the zeolite catalyst further comprises copper (Cu) having a Cu content corresponding to a Cu / Al ratio selected from 0.2 to 0.5, 0.25 to 0.45, and 0.3 to 0.

4.

9. A catalyst article effective for reducing nitrogen oxides (NOx) from lean-burn engine exhaust gas, comprising a substrate carrier having the selective catalytic reduction (SCR) catalyst described in claim 1.

10. The catalyst article according to claim 9, wherein the substrate carrier is a honeycomb substrate and is optionally composed of a metal or a ceramic.

11. The catalyst article according to claim 9, wherein the honeycomb substrate carrier is a flow-through substrate or a wall-flow filter.

12. An exhaust gas treatment system, A lean-burn engine that generates exhaust flow, An exhaust gas treatment system comprising a catalytic article according to claim 9, which is positioned downstream of the lean-burn engine and is in fluid communication with the exhaust gas flow.

13. below: a. A diesel oxidation catalyst (DOC) positioned upstream of the catalyst article, b. A filter positioned upstream of the catalyst article, and c. The exhaust gas treatment system according to claim 12, further comprising one or more ammonia oxidation catalysts (AMOX) positioned downstream of the catalyst article.

14. A process for preparing a selective catalytic reduction (SCR) catalyst, (a) preparing the catalyst according to claim 1 or 2, (b) Applying the catalyst as a coating on a ceramic or metal honeycomb substrate monolith, (d) Drying the coated monolith, (e) A process comprising firing the coated monolith at a temperature in the range of 400°C to 800°C.

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