WO2021041201A2

WO2021041201A2 - Catalyst compositions and methods of preparation and use thereof

Info

Publication number: WO2021041201A2
Application number: PCT/US2020/047380
Authority: WO
Inventors: Subramanian PRASAD; Ivan Petrovic; Bradley F. Chmelka; Zachariah J. BERKSON; Michael Brandon SCHMITHORST
Original assignee: Basf Corp.; The Regents Of The University Of California
Priority date: 2019-08-23
Filing date: 2020-08-21
Publication date: 2021-03-04
Also published as: WO2021041201A3

Abstract

Disclosed are catalyst compositions containing a hydrogen/copper-chabazite (H/Cu- CHA) zeolite with silica (SiO2) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5:1 to about 50:1 and about 0.1 wt% to about 5.0 wt% of a copper oxide. Also disclosed are methods of preparation and methods of use thereof.

Description

CATALYST COMPOSITIONS AND METHODS OF PREPARATION AND USE THEREOF

FIELD

[0001] This disclosure relates to a catalyst composition having a hydrogen/copper-chabazite (H/Cu-CHA) zeolite, for example, to convert methanol or propanol to olefins. The disclosure also relates to methods of preparing such catalyst compositions.

BACKGROUND

[0002] Zeolites are aluminosilicate crystalline materials having substantially uniform pore sizes which, depending upon the type of zeolite and the type and amount of cations included in the zeolite lattice, typically range from about 3 to 10 Angstroms in diameter. Synthetic and natural zeolites and their use in promoting certain reactions, including the selective reduction of nitrogen oxides with ammonia in the presence of oxygen, are well known in the art.

[0003] Aluminosilicate zeolites are of considerable technological interest because their high surface areas, well-defined sub-nanometer pores, and cation exchange sites enable catalytic applications for hydrocarbon conversion or pollution reduction. The catalytic properties of aluminosilicate zeolites arise from the non-stoichiometric substitution of AlCfi^3-, AlO₂ tetrahedra for SiO₄ ^2-, SiO₂ tetrahedra, respectively, which introduces negative framework charges that are balanced by exchangeable cations. In their solid-acid (H⁺) forms, aluminosilicate zeolites, such as faujasite (Y zeolite) and chabazite (SSZ-13), are highly active as heterogeneous catalysts for hydrocarbon rearrangement reactions including cracking or the conversion of methanol to light olefins. In their copper-exchanged forms, aluminosilicate zeolites are of interest as catalysts that reduce NO_x emissions in automobile exhaust streams by converting NO_x compounds to N₂ and H₂O in the presence of a sacrificial reductant. Different copper-exchanged zeolites exhibit very different reactivities, about which little is known at an atomic level. Among the reasons for such differences are the distinct local compositions and atomic environments of framework heteroatoms, such as aluminum, that directly influence the distributions of exchangeable cations that are often catalytically important sites. Measuring and understanding the influences of framework heteroatom environments on catalytic activity and selectivity has been exceedingly challenging, in part due to the disordered distributions of heteroatoms within zeolite frameworks which preclude detailed analysis by conventional scattering or spectroscopic techniques. By comparison, solid-state nuclear magnetic resonance (NMR) spectroscopy measurements are sensitive to the local chemical environments of NMR-active species (e.g., ¹H, ²⁷ Al, and ²⁹Si) in aluminosilicate zeolites. Solid-state NMR spectroscopy can be used to identify different kinds of ²⁷ Al and ²⁹Si species and establish their relative quantities and proximities, including to exchangeable copper cations.

[0004] Many industrially important reactions operate under high temperature conditions for high conversion and desirable selectivity. Examples include selective catalytic reduction (SCR) of NO_x from diesel exhaust streams for automotive applications and methanol dehydration to form olefins. The presence of water, either as an impurity in the feed stream or as a reaction byproduct, can result in irreversible degradation in the performance of heterogeneous zeolite catalyst materials due to the effects of particle sintering or framework dealumination under high temperature hydrothermal conditions. The influences of harsh high-temperature conditions in the presence of water on zeolite framework environments have been difficult to determine due to the complex and varied effects and distributions of degradation products, which are challenging to characterize. For high-alumina zeolites used as supports for catalytic cracking reactions, such as faujasite, hydrothermal treatment leads to extensive framework dealumination and generation of “extraframework” Al species that can occupy complicated distributions of sites within the zeolite frameworks and at the surfaces of the zeolite catalyst particles. Extraframework aluminum species have been well established to influence the catalytic properties of zeolite materials. For high-silica zeolites with emerging applications such as chabazite (SSZ-13) catalysts, elucidating the types and distributions of hydrothermal degradation products is more challenging.

[0005] There is a desire to prepare improved catalyst compositions having high hydrothermal stabilities, for example, to convert methanol or propanol to olefins.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1(a) shows methanol conversion as a function of time for H-chabazite after calcination at 450 °C (dashed line) and subsequent steam-treatment at 750 °C (10% H₂O, 6 h, dotted line) or Cu-exchange (3.3 wt% CuO), steam-treatment at 750 °C (10% H₂0, 6 h), back-exchange with NH₄ ⁺, and calcination at 450 °C to produce the H/Cu-form (solid line). [0007] FIG. 1(b) shows the temperature program used during the reaction tests in Example 1

[0008] FIG. 1(c) shows the reaction yields of ethylene as a function of reaction time for a H- chabazite catalyst (dashed line), a steam-aged H-chabazite (dotted line) and a steam-aged H/Cu-chabazite catalyst (dashed line). [0009] FIG. 1(d) shows the reaction yields of propylene as a function of reaction time for a H-chabazite catalyst (dashed line), a steam-aged H-chabazite (dotted line), and a steam-aged H/Cu-chabazite catalyst (dashed line).

[0010] FIG. 1(e) shows the reaction yields of butylene as a function of reaction time for a H- chabazite catalyst (dashed line), a steam-aged H-chabazite (dotted line), and a steam-aged H/Cu-chabazite catalyst (dashed line).

[0011] FIG. 2 shows a simulated XRD pattern for the idealized CHA framework (inset), adapted from the International Zeolite Association database, XRD patterns of Na/H-chabazite after calcination at 450 °C and subsequent steam-treatment at 750 °C or after Cu-exchange (to 3.3 wt% CuO) and calcination at 450 °C with subsequent steam-treatment at temperatures of 750 °C, (f) 850 °C, and 950 °C. For all of the steam treatments, the materials were aged at the specified temperature in 10% H₂O/air for 6 h.

[0012] FIG. 3 shows solid-state 2D ²⁷Al{²⁹Si} D-HMQC spectrum of Na/H chabazite acquired at 9.4 T, 95 K, and 8 kHz MAS. Solid-state ID ²⁷ A1 echo and ²⁹Si{¹H} CPMAS spectra acquired under the same conditions are shown along the horizontal and vertical axes, respectively, for comparison with the ID projections of the 2D spectrum.

[0013] FIG. 4 shows Solid-state 2D ²⁷Al{²⁹Si} D-HMQC spectrum of steam-aged and back- exchanged H/Cu chabazite acquired at 9.4 T, 95 K, and 8 kHz MAS. Solid-state ID ²⁷ A1 echo and ²⁹Si{¹H} CPMAS spectra acquired under the same conditions are shown along the horizontal and vertical axes, respectively, for comparison with the ID projections of the 2D spectrum. The sample had 10 wt% added alumina.

[0014] FIG. 5 shows solid-state 2D ²⁷ A1 3QMAS spectra of (a) Na/H chabazite and (b) Cu- exchanged chabazite (3.3 wt% CuO, acquired at 18.8 T, 298 K, and 20 kHz MAS. The solid- state ID single-pulse ²⁷ A1 MAS spectra acquired under the same conditions are shown along the horizontal axes for comparison with the ²⁷ A1 single-quantum projections of the 2D spectra. The ²⁷ A1 triple-quantum projections from the 2D spectra are shown along the vertical axes. Horizontal slices extracted at the triple-quantum shifts indicated by the dotted lines are shown to the right of the 2D spectra.

[0015] FIG. 6 shows solid-state ID single pulse ²⁷ A1 spectra of H-chabazite after calcination at 450 °C and subsequent steam aging at 750 °C, and of Cu-exchanged chabazite (3.3 wt% CuO) before and after steam aging at 750 °C. The spectra were acquired at 18.8 T, 20 kHz MAS, and 295 K.

[0016] FIG. 7 shows a schematic of a methanol -to-olefm reaction system operable with catalysts as disclosed herein. [0017] FIG. 8 shows methanol conversion as a function of time for commercial SAPO-34 (thin line), H-chabazite after calcination at 450 °C (dashed line) and subsequent steam- treatment at 750 °C (10% H2O, 6 h) (dotted line) or Cu-exchange (3.3 wt % CuO), steam- treatment at 750 °C (10% H2O, 6 h), back-exchange with NH₄ ⁺, and calcination at 450 °C to produce the H/Cu-form (solid line). The temperature program used during the reaction tests is shown in (b).

[0018] FIG. 9 shows the conversion of methanol to C₂-C₄ olefins as functions of temperature and time for the H/Cu-form of this sample.

[0019] FIG. 10(a) shows a 2D ²⁷Al{²⁹Si} D-HMQC spectrum of H/Cu-chabazite zeolite catalyst sample.

[0020] FIG. 10(b) shows a 2D ²⁷Al{²⁹Si} J-HMQC spectrum of the H-chabazite catalyst sample.

BRIEF SUMMARY

[0021] According to various embodiments, described herein is a catalyst composition, comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

[0022] Further described herein according to embodiments is a method of preparing a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite, the method comprising preparing a copper-CHA (Cu-CHA) zeolite comprising copper oxide in an amount of about 0.1 wt% to about 5.0 wt%; steam-aging the Cu-CHA zeolite to re distribute the Cu²⁺ ions and stabilize cages of the Cu-CHA zeolite and to prepare a steam- aged Cu-CHA zeolite; and preparing the H/Cu-CHA zeolite by back exchange of the steam- aged Cu-CHA zeolite with ammonium (NH₄ ⁺) ions, wherein the H/Cu-CHA zeolite comprises copper oxide in an amount of about 0.1 wt% to about 5.0 wt%.

[0023] In yet further embodiments, described herein is a method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze a methanol-to-olefm (MTO) reaction, the method comprising converting MTO in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper- chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica- alumina ratio (SAR) of about 10:1 to about 45:1, or about 30:1, or about 20:1 and about 0.1 wt% to about 5.0 wt% of a copper oxide. [0024] According to various embodiments, described herein is a method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze an ethanol-to-ethylene reaction, the method comprising converting ethanol to ethylene in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

[0025] In further embodiments, described herein is a method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite in a selectoforming process to catalyze shape-selective cracking of short linear alkanes to increase octane number of light naphtha, the method comprising operating the selectoforming process in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide. [0026] In yet further embodiments, describe herein is a method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to synthesize methylamines, the method comprising synthesizing methylamines in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide. [0027] According to further embodiments, describe herein is a method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze ethanol dehydration, the method comprising performing an ethanol dehydration process in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

[0028] In yet further embodiments, disclosed is a method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze an ethylene oligomerization-cracking process, the method comprising performing an ethylene oligomerization-cracking process in the presence of the catalyst composition, wherein the H- CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5:1 to about 50:1 and about 0.1 wt% to about 5.0 wt% of a copper oxide. DETAILED DESCRIPTION

[0029] Described herein are various embodiments of a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite and methods of preparation and use thereof. It is to be understood that the invention is not limited to the details of construction or process steps set forth in the following description. The invention is capable of other embodiments and of being practiced or being carried out in a variety of ways.

[0030] Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments” or “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

[0031] As used herein, the singular forms “a,” “an,” and “the” include plural references unless the context clearly indicates otherwise. Thus, for example, reference to “a catalyst material” includes a single catalyst material as well as a mixture of two or more different catalyst materials.

[0032] As used herein, the term “about” in connection with a measured quantity, refers to the normal variations in that measured quantity as expected by one of ordinary skill in the art in making the measurement and exercising a level of care commensurate with the objective of measurement and the precision of the measuring equipment. In certain embodiments, the term “about” includes the recited number ±10%, such that “about 10” would include from 9 to 11.

[0033] The term “at least about” in connection with a measured quantity refers to the normal variations in the measured quantity, as expected by one of ordinary skill in the art in making the measurement and exercising a level of care commensurate with the objective of measurement and precisions of the measuring equipment and any quantities higher than that. In certain embodiments, the term “at least about” includes the recited number minus 10% and any quantity that is higher such that “at least about 10” would include 9 and anything greater than 9. This term can also be expressed as “about 10 or more.” Similarly, the term “less than about” typically includes the recited number plus 10% and any quantity that is lower such that “less than about 10” would include 11 and anything less than 11. This term can also be expressed as “about 10 or less.”

[0034] Unless otherwise indicated, all parts and percentages are by weight. Weight percent (wt. %), if not otherwise indicated, is based on an entire composition free of any volatiles, that is, based on dry solids content.

[0035] Although the disclosure herein is with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the compositions and methods without departing from the spirit and scope of the invention. Thus, it is intended that the invention include modifications and variations that are within the scope of the appended claims and their equivalents.

Catalyst Compositions

[0036] According to various embodiments, catalyst compositions as described herein can include a hydrogen/copper-chabazite (H/Cu-CHA) zeolite containing silica (SiO₂), alumina (AI₂O₃) and a copper oxide. According to embodiments, the alumina can be present in an amount of about 2.0 wt% to about 25 wt%, or about 3.0 wt% to about 22 wt%, or about 5.0 wt% to about 20 wt%, or about 6.0 wt% to about 15 wt%, or about 8.0 wt% to about 12 wt%, or about 10 wt%. The silica-to-alumina ratio (SAR) can be about 5: 1 to about 50: 1, about 10:1 to about 45:1, or about 15:1 to about 40:1, or about 20:1 to about 35:1, or about 20:1, or about 30: 1 by weight. According to embodiments, the copper oxide can be in an amount of about 0.1 wt% to about 5.0 wt%, about 0.2 wt% to about 4.0 wt%, or about 0.3 wt% to about 3.0 wt%, or about 0.4 wt% to about 2.0 wt%, or about 0.5 wt% to about 1.0 wt %, or about 0.6 wt% to about 0.9 wt%. In embodiments, the catalyst composition can contain an elemental silicon-to-aluminum ratio of about 2.5: to about 25:1, or about 5: 1 to about 20: 1, or about 10: 1 to about 15 : 1 , or about 15:1. In embodiments, the copper oxide can be at least one of a copper (I) oxide (CU2O), a copper (II) oxide (CuO), a copper (III) oxide (CU2O3) or a copper peroxide (CuCh).

[0037] According to various embodiments, the catalyst compositions containing the H/Cu- CHA zeolite and/or the H/Cu-CHA zeolite can be in the form of a powder, particles, pellets, extrudates, granules, beads or combinations thereof. In embodiments, the catalyst composition can be in the form of pellets or extrudates. The pellets or extrudates can be in the shape of at least one of a sphere, cylinder, cube or tetrahedron. The pellets or extrudes can have a diameter or width of about 0.1 mm to about 10 mm. [0038] According to certain embodiments, the catalyst composition can further include a substrate, wherein the H/Cu-CHA zeolite is disposed on the substrate. The material of the substrate can be a ceramic, a metal or a combination thereof. In embodiments, the ceramic can include a cordierite, cordierite-alumina, silicon nitride, zircon mullite, spodumene, alumina-silica magnesia, zircon silicate, sillimanite, magnesium silicate, zircon, metalize, alpha-alumina, aluminosilicate or combinations thereof. In embodiments, the metal can include titanium, stainless steel, iron, nickel, chromium, aluminum, manganese, copper, vanadium, alloys thereof or combinations thereof. According to certain embodiments, the catalyst composition can further include an oxide layer on a surface of the substrate. In various embodiments, the substrate can be a monolithic substrate, a corrugated sheet substrate, a wall-flow filter substrate or an open cell foam substrate. In embodiments, the monolithic substrate can include fine, parallel gas flow passages extending therethrough from an inlet to an outlet of the substrate as descrived in Heck, et al, Catalytic Air Pollution Control , pp. 34-38 (Wiley, 2009). In further embodiments, the H/Cu-CHA zeolite is disposed as a washcoat on a surface of the substrate. In embodiments, the substrate can have a honeycomb structure, where gas flow passages of the honeycomb structure include at least one of a trapezoidal, rectangular, square, sinusoidal, hexagonal, oval or circular cross-section. The substrate can include about 60 to about 400 gas flow passages.

[0039] According to embodiments, catalyst compositions as described herein can have a lifetime of about 30 min to about 12 hours, or about 1 hour to about 11 hours, or about 2 hours to about 9 hours, or about 3 hours to about 8 hours, or about 7 hours, or about 7.5 hours, or about 8 hours, or about 8.5 hours, when used to catalyze a methanol -to-olefm reaction at a reaction temperature of about 100 °C to about 600 °C, or about 150 °C to about 550 °C, or about 200 °C to about 500 °C, or about 250 °C to about 450 °C, or about 300 °C.

In embodiments, the performance of the H/Cu-CHA catalyst composition is not reduced or affected in the presence of water or moisture.

Methods of Preparing the Catalyst Compositions

[0040] Further disclosed herein are methods of preparing catalyst compositions as described above. The methods can include preparing a copper-CHA (Cu-CHA) zeolite comprising copper oxide; steam-aging the Cu-CHA zeolite to re-distribute the Cu ions and stabilize cages of the Cu-CHA zeolite and to prepare a steam-aged Cu-CHA zeolite; and preparing the H/Cu- CHA zeolite by back exchange of the steam-aged Cu-CHA zeolite with ammonium (NH₄ ⁺) ions, wherein the H/Cu-CHA zeolite comprises a copper oxide. In at least one embodiment, the method includes preparing a copper-CHA (Cu-CHA) zeolite comprising copper oxide in an amount of about 0.1 wt% to about 5.0 wt%; steam-aging the Cu-CHA zeolite to re- distribute the Cu ions and stabilize cages of the Cu-CHA zeolite and to prepare a steam-aged Cu-CHA zeolite; and preparing the H/Cu-CHA zeolite by back exchange of the steam-aged Cu-CHA zeolite with ammonium (NH₄ ⁺) ions, wherein the H/Cu-CHA zeolite comprises copper oxide in an amount of about 0.1 wt% to about 5.0 wt%.

[0041] In embodiments, the method further includes preparing a CHA zeolite and preparing the copper-CHA (Cu-CHA) zeolite from the CHA zeolite. Preparing the CHA zeolite can include preparing an ammonium chabazite ( (NH₄-CHA) zeolite. Preparing the Cu-CHA zeolite can include ion exchange of the CHA zeolite with Cu²⁺ ions. In embodiments, preparing the Cu-CHA zeolite can include mixing (NH₄-CHA zeolite with a copper (II) sulfate solution to form a mixture. The method may include adding nitric acid to the mixture to adjust pH to about 2.5 to about 4.5, or about 3.5. In embodiments, the copper (II) sulfate solution can be at a concentration of about 0.1 M to about 10.0 M, or about 0.5 M to about 5.0 M, or about 1.0 M. The method can further include agitating the mixture at a temperature of about 70°C to about 90°C, or about 80°C for about 30 minutes to about 2 hours, or about 1 hour.

[0042] The steam-aging can be performed at a temperature of about 500 °C to about 1,000 °C, or about 650 °C to about 950 °C. The Cu-CHA zeolite can be in about 10 wt% water for about 2 hours to about 16 hours, or about 3 hours to about 12 hours, or about 4 hours to about 8 hours, or about 5 hours.

[0043] According to embodiments, preparing the H/Cu-CHA zeolite can include, following the back-exchange, calcining in air at a temperature of about 300 °C to about 600 °C, or about 350 °C to about 500 °C, or about 450 °C.

[0044] According to various embodiments, the method can further include depositing the H/Cu-CHA zeolite onto a substrate. The depositing can include washcoating the H/Cu-CHA zeolite onto the substrate.

Methods of Using the Catalysts compositions

[0045] Described herein are various methods of using catalysts compositions as disclosed herein. According to various embodiments, disclosed is a method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze a methanol-to-olefm (MTO) reaction, the method comprising: converting MTO in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper- chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) and a copper oxide. In at least one embodiment, the method includes using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze a methanol-to- olefin (MTO) reaction, the method comprising: converting MTO in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and about 2.0 wt% to about 25 wt% alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 10: 1 to about 45: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

[0046] In embodiments, the converting can be at a temperature of about 100 °C to about 600 °C, or about 150 °C to about 550 °C, or about 200 °C to about 500 °C, or about 250 °C to about 450 °C, or about 300 °C or about 250 °C, or about 300 °C, or about 350 °C, or about 400 °C.

[0047] According to embodiments, the catalyst composition can have a lifetime of about 30 min to about 400 min, or about 40 min to about 350 min, or about 50 min to about 300 min, or about 60 min to about 250 min, or about 70 min to about 200 min, or about 80 min to about 150 min, or about 90 to about 100 min, or about 110 min, or about 115 min, or about 120 min, or about 125 min. In embodiments, the catalyst composition can be resistant to hydrothermal degradation.

[0048] Converting the MTO comprises flowing methanol vapor, optionally in a carrier gas, over the catalyst composition. The carrier gas can include argon, helium or a combination thereof.

[0049] The method catalyst composition may be in a packed-bed reactor or a fluidized bed reactor. The packed-bed reactor or fluidized bed reactor can be at a temperature of about 100 °C to about 600 °C, or about 150 °C to about 550 °C, or about 200 °C to about 500 °C, or about 250 °C to about 450 °C, or about 300 °C or about 250 °C, or about 300 °C, or about 350 °C, or about 400 °C.

[0050] In embodiments, the catalyst composition can have an olefin selectivity of at least about 0.1 to about 0.4. In embodiments, the catalyst composition can have an ethylene selectivity of at least about 0.35, or at least about 0.36, or at least about 0.37, or at least about 0.38, or at least about 0.39, or at least about 0.40. In embodiments, the catalyst composition can have a propylene selectivity of at least about 0.35, or at least about 0.36, or at least about 0.37, or at least about 0.38, or at least about 0.39, or at least about 0.40. According to embodiments, the H/Cu-CHA catalyst composition can have an olefin yield of about 5 times greater, or about 10 times greater, or about 20 times greater, or about 30 times greater, or about 50 times greater, or about 100 times greater than a comparative H-CHA catalyst composition or a comparative H-CHA catalyst composition that has been steam aged.

[0051] According to embodiments, described is a method of using a catalyst composition as described herein to catalyze an ethanol-to-ethylene reaction, the method comprising: converting ethanol to ethylene in the presence of the catalyst composition. In at least one embodiment, the method includes using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze an ethanol-to-ethylene reaction, the method comprising: converting ethanol to ethylene in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu- CHA) zeolite comprising silica (SiO₂) and about 2.0 wt% to about 25 wt% alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

[0052] According to various embodiments, described is a method of using a catalyst composition as described herein to catalyze shape-selective cracking of short linear alkanes to increase octane number of light naphtha, the method comprising: operating the selectoforming process in the presence of the catalyst composition. In at least one embodiment, the method includes using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite in a selectoforming process to catalyze shape-selective cracking of short linear alkanes to increase octane number of light naphtha, the method comprising: operating the selectoforming process in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu- CHA) zeolite comprising silica (SiO₂) and about 2.0 wt% to about 25 wt% alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

[0053] Also disclosed is a method of using a catalyst composition as described herein, the method comprising: synthesizing methylamines in the presence of the catalyst composition.

In at least one embodiment, the method includes using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to synthesize methylamines, the method comprising: synthesizing methylamines in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and about 2.0 wt% to about 25 wt% alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide. [0054] Further disclosed is a method of using a catalyst composition as described herein, the method comprising: performing an ethanol dehydration process in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu- CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) and a copper oxide. In at least one embodiment, the method includes using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze ethanol dehydration, the method comprising: performing an ethanol dehydration process in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu- CHA) zeolite comprising silica (SiO₂) and about 2.0 wt% to about 25 wt% alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

[0055] According to various embodiments, disclosed is a method of using a catalyst composition as described herein to catalyze an ethylene oligomerization-cracking process. In at least one embodiment, the method includes using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze an ethylene oligomerization cracking process, the method comprising: performing an ethylene oligomerization-cracking process in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and about 2.0 wt% to about 25 wt% alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

EXAMPLES

Example 1 — Catalytic Methanol-to-Olefin (MTO) reaction properties of H- andH/Cu- chabazite zeolite catalysts at a silica-to-alumina ratio of about 30:1 (SAR=30)

[0056] The catalytic properties of chabazite materials were tested by monitoring the conversion of methanol to olefins at 300 °C. See FIG. 1(a). A schematic of the experimental reactor setup is shown in FIG. 7 and the temperature program is set forth in FIG. 1(b). Methanol was stored in a tank under an argon blanket. Saturated methanol vapor flowed from the tank to a packed bed reactor filled with zeolite powder. The packed bed reactor was heated by a furnace at about 300 °C to about 500 °C. The reactor effluent flowed through an online mass spectrometer for measurement.

[0057] As shown in FIG. 1, methanol conversion was measured as a function of time on stream for calcined H-chabazite before and after steam-aging at 750 °C (10% ThO, 6 h) as well as after Cu-exchange, steam aging at 750 °C (10% H2O, 6 h), and subsequent back- exchange with NH₄ ⁺ and calcination to produce the stabilized H/Cu-form. Without being bound by any particular theory, the methanol-to-olefm (MTO) reaction over heterogeneous catalysts like H-chabazite is characterized by an initial induction period, during which a pool of cyclic organic intermediate species is formed within the chabazite zeolite cages. During the induction period (40-50 minutes), the primary reaction products were H₂ and CH₄, indicating decomposition of methanol was the dominant reaction mechanism with little formation of olefins. After the induction period, C_2-4 olefins are formed, with the H-chabazite catalyst exhibiting complete conversion of methanol over the entire reaction period. By comparison, the steam-aged H-chabazite catalyst reaches a lower maximum conversion (0.95) after ca. 90 minutes on stream, after which the methanol conversion decreases consistent with deactivation of the catalyst. Notably, the steam-aged H/Cu-chabazite catalyst reaches complete conversion of methanol and exhibits no deactivation over the course of the reaction period, consistent with improved catalytic stability compared to the steam-aged H- form. For comparison, a commercial H-SAPO-34 catalyst was also tested, as shown in FIG. 8, though this catalyst displays a lower maximum conversion (0.8 at 55 min.) compared to the chabazite materials, after which the conversion decreases to ca. 0.25. More particularly,

FIG. 8 shows methanol conversion as a function of time for commercial SAPO-34 and H- chabazite after calcination at 450 °C and subsequent steam-treatment at 750 °C (10% H2O, 6 h) or Cu-exchange (3.3 wt % CuO), steam-treatment at 750 °C (10% H2O, 6 h), back- exchange with NH-G, and calcination at 450 °C to produce the H/Cu-form . The temperature program used during the reaction tests is also shown in FIG. 8.

[0058] The product selectivities for C₂-C₄ olefins for H-chabazite before and after steam aging and the back-exchanged steam-aged H/Cu-chabazite catalyst materials were determined as shown in FIGs 1(c), 1(d) and 1(e). For the H-chabazite catalyst, the highest selectivity is for ethylene, then propene and butene. The steam-aged H-chabazite catalyst yields about 0.22 butene and reduced selectivity for propene, but a comparatively higher selectivity for ethylene. By comparison, the steam-aged H/Cu-chabazite catalyst shows high yields for ethylene (up to 0.45 over the reaction period studied), with good yields of propene (up to 0.35) and smaller quantities of butene. The different product distributions measured for the different catalyst materials indicates that post-synthetic processing of chabazite MTO catalysts, including ion-exchange and steam treatment, provides a means to influence the selectivity of the MTO reaction. Overall, the MTO reaction tests provide evidence that the presence of Cu²⁺ ions in chabazite during steam treatment led to improved overall catalytic efficiency after the Cu-chabazite material is converted to H form.

[0059] Table 1 shows the olefin mole fractions produced at 100 min time on stream (50 min at 300 °C).

Table 1 - Olefin mole fractions normalized with respect to total olefins in outlet at 100 min TOS (50 min at 300 °C)

Example 2 — Long-range crystallinity and order in H- and Cu-exchanged chabazite zeolite catalysts

[0060] The influences of ion exchange and hydrothermal treatment on the long-range crystallinity of the Na/H- and Cu-chabazite materials were assessed by wide-angle X-ray diffraction (WAXS) as shown in FIG. 2. All of the narrow reflections in the WAXS patterns of the different Na/H-chabazite and Cu-chabazite materials were indexable to the CHA framework structure (FIG. 2), confirming that the ion exchange and calcination processes did not substantially influence the framework structure and long-range order of the zeolite materials. As shown in FIG. 2, the positions and widths of the X-ray reflections were the same before and after steam-aging of Na/H-chabazite at 750 °C for 6 h in 10% H2O, as well as after Cu-exchange and subsequent steam treatment at 750 °C. After steam treatment at temperatures higher than 750 °C, long-range crystalline ordering of the Cu-chabazite materials diminishes (FIG. 2). Specifically, after steam treatment at 850 °C, a broad, weak reflection at about 22° 20 (d-spacing~0.4 nm) is observed, corresponding to an X-ray amorphous component of the material (FIG. 2). After steam treatment at 950 °C, no reflections indexable to the CHA framework are detected, and only a broad reflection at 22° 20 remains, indicating that the high-temperature steam-aging conditions lead to complete loss of long range crystalline ordering in the material (FIG. 2). The X-ray diffraction measurements were unable to distinguish between Si and A1 atoms due to their similar electron densities and therefore provided limited information on the influences of steam aging on the types and distributions of A1 heteroatoms and their associated exchangeable cations. Example 3 — Elucidating ion exchange sites in H- and Cu-exchanged chabazite zeolite catalysts

[0061] By comparison to the X-ray diffraction results discussed above, solid-state nuclear magnetic resonance (NMR) spectroscopy measurements are sensitive to the local chemical environments of ¹H, ²⁷ Al, and ²⁹ Si atoms in aluminosilicate zeolites and can be used to identify different kinds of ²⁷ Al and ²⁹Si species and establish their relative quantities and proximities, including to exchangeable copper cations. For example, two-dimensional ²⁷Al{²⁹Si} dipolar-mediated heteronuclear multiple quantum coherence (D-HMQC) NMR spectra can selectively detect and correlate ²⁷ Al and ²⁹Si spins from ²⁷Al-²⁹Si spin-pairs that are dipole-dipole coupled over sub-nanometer distances. The 2D ²⁷Al{²⁹Si} D-HMQC spectrum of Na/H chabazite show a 2D contour plot with normalized ²⁷ Al and ²⁹Si frequency axes with normalized frequency units of Hz/MHz (ppm). Correlated signal intensities in the 2D D-HMQC spectrum unambiguously establishes the relative proximities and nanoscale interactions of the corresponding ²⁷ Al and ²⁹Si species.

[0062] The 2D ²⁷A1 (²⁹Si } D-HMQC spectrum of Na/H chabazite shown in FIG. 3 establishes the presence of framework and extraframework ²⁷ Al species within the chabazite zeolite nanopores. The spectrum shows a ²⁷A1^IV signal at 57 ppm that correlates with ²⁹Si species at - 112, -104 to -106, -100, and -95 ppm, which are assigned respectively to z)₄(0A1), Q4(l Al), (L(2A1), and Q₃{1Al) species. These correlated intensities are consistent with the proximities of framework ²⁷A1^IV species with different nearest- and next-nearest neighbor ²⁹Si silicate species. An additional signal intensity at 25 ppm in the ²⁷ Al dimension correlates to a ²⁹Si signal at -104 ppm from Q₄(1Al) species, while a ²⁷ Al signal at -2 ppm was correlated to ²⁹Si signals at -100, -104 to -106, and -112 ppm from 0₄(2 Al), z)₄(1 Al), and Q_A(0 Al) framework silicate moieties. These correlated signals are consistent with the presence of different ²⁷A1^V and ²⁷A1^IV extraframework cations within the zeolite such as Al(OH)²⁺ and Al(OH)2⁺. On the basis of the correlated intensities in the 2D D-HMQC spectrum, the ²⁷A1^V signal is assigned to monovalent Al(OH)2⁺ cations near framework Q₄(1Al) sites, while the ²⁷A1^VI signal is assigned to divalent Al(OH)²⁺ cations near Q₄(2Al) sites.

[0063] The distribution of framework ²⁷ Al species in Cu-chabazite is largely unchanged by the hydrothermal treatment and ion exchange processes, as established by the 2D ²⁷Al{²⁹Si} D-HMQC spectrum of steam-aged H/Cu chabazite shown in FIG. 4. The inhomogeneously- broadened ²⁷ Al signal at 58 ppm from framework ²⁷A1^IV species is correlated to ²⁹Si signals at -111, -105, -99, and -95 ppm, which arise respectively from Q₄(1Al,) Q₄(1Al), Q₄(1Al), and Q₃(1Al) species. No correlated signal intensity is detected at ²⁷ A1 shifts of 31 or 8 ppm in the 2D ²⁷A1 {²⁹Si } spectrum, indicating that the ²⁷A1^V and ²⁷A1^VI species with signals in these frequency regions are extraframework and segregated on the nanoscale from the aluminosilicate zeolite framework. The ID ²⁹Si projection of the 2D ²⁷A1 {²⁹Si } D-HMQC spectrum of steam-aged H/Cu chabazite (FIG. 5) is nearly identical to the ID ²⁹Si projection of the corresponding 2D spectrum of Na/H chabazite (FIG. 4), indicating that the distributions of framework ²⁷ Al atoms are nearly the same in both materials. This confirms that the presence of Cu²⁺ ions in chabazite stabilize framework Al species on hydrothermal treatment.

[0064] The spectral resolution of solid-state ²⁷ Al NMR spectra is limited because the quadrupolar (/= 5/2) character of ²⁷ Al nuclei typically yield broad NMR signals. The resolution can be improved by conducting NMR measurements at very high magnetic fields, or by using 2D multiple-quantum MAS (MQMAS) methods to mitigate the effects of anisotropic quadrupolar broadening associated with the spin 5/2 ²⁷ Al nuclei. For example,

2D ²⁷ Al triple-quantum MAS (3QMAS) NMR spectra as shown in FIG. 5, acquired at 18.8 T, yield improved spectral resolution compared to the ID ²⁷ Al spectra by averaging anisotropic second-order quadrupolar interactions and spreading the signals into a 2D frequency map with single-quantum (SQ) and triple-quantum (TQ) axes on the abscissa and ordinate, respectively. The SQ dimension manifests both anistropic and isotropic contributions to the ²⁷ Al signal linewidths, while the TQ dimension reflects only the isotropic contributions, allowing the different ²⁷ Al signals to be resolved and identified.

[0065] Specifically, ²⁷ Al signals from different types of tetrahedrally- and octahedrally- coordinated ²⁷ Al species in Na/H- and Cu-chabazite are resolved in the 2D ²⁷ Al 3QMAS spectra as shown in FIG. 5. The 2D MQMAS spectrum of Na/H-chabazite (FIG. 5a) resolved two ²⁷ Al signals at 59 ppm in the SQ dimension and 60 or 65 ppm in the TQ dimension, which are assigned to different types tetrahedrally-coordinated ²⁷Al^IVspecies. The ²⁷A1^IV signals at a TQ shift of 60 ppm exhibit a relatively narrow linewidth (ca. 2 ppm full- width-half-maximum, FWHM) in both the SQ and TQ dimensions, while the ²⁷A1^IV signal at a TQ shift of 65 ppm exhibit a significantly broader linewidth (ca. 9 ppm FWHM). The presence of two different types of ²⁷A1^IV species in the Na/H chabazite material is surprising because the chabazite framework structure has only one distinct type of tetrahedral (T) site, which can be occupied by either Si or Al atoms. Similar ²⁷A1^IV signals are detected in MQMAS NMR analyses of other zeolites including Y zeolite (FAU structure), which also possesses a single crystallographic T site. The narrow ²⁷A1^IV signal is typically assigned to tetrahedrally-coordinated ²⁷ A1 species in the zeolite framework associated with H⁺ and/or Na⁺ cations that balance the framework charge imbalance localized on the AIO4^3- tetrahedra. The origin of the broad ²⁷A1^IV signal is contentious, and the signal has been attributed variously to ²⁷A1^IV species in the vicinity of defect sites, framework ²⁷A1^IV species near cationic extraframework aluminum species or H⁺, and distorted tetrahedrally-coordinated extraframework ²⁷ A1 cations trapped within faujasite sodalite cages. In the Na/H-chabazite material studied here, the broad ²⁷A1^IV signal is evidenced to arise from framework ²⁷A1^IV species associated with charge-balancing extraframework aluminum cations on the basis of the additional solid-state ID quantitative ²⁷ A1 and ²⁹Si, and 2D ²⁷Al{²⁹Si} NMR spectra and analyses. As shown in FIG. 5, the 2D ²⁷ A1 MQMAS show an additional ²⁷ A1 signal at 4 ppm in the TQ dimension from ²⁷A1^VI species. The origin of similar ²⁷A1^VI signals in the ²⁷ A1 NMR spectra of other aluminosilicate zeolite materials is also debated; such signals have been variously attributed to ²⁷ A1 species in extraframework alumina particles or extraframework cationic aluminum species. While generally associated with extraframework aluminum species, ²⁷A1^VI NMR signals also have been attributed to framework ²⁷A1^IV species that coordinate to water molecules near defect sites formed on partial hydrolysis of the framework.

[0066] The types and distributions of ²⁷ A1 species change on ion-exchange of Na/H-chabazite with Cu, as established by comparison of the 2D ²⁷ A1 3QMAS spectra of Na/H- and Cu- chabazite as shown in FIG. 5. The 2D spectrum of Cu-chabazite (FIG. 5b) show narrow and broad ²⁷A1^IV signals at 59 and 65 ppm in the TQ dimension, respectively, which are similar to the ²⁷A1^IV signals resolved in the spectrum in FIG. 5 and assigned to tetrahedrally- coordinated ²⁷A1^IV species associated with either H⁺ or extraframework Al³⁺ charge-balancing cations. Notably, the relative intensity of the broad ²⁷A1^IV signal is diminished after Cu exchange indicating a decrease in the population of framework A1^IV sites associated with extraframework A1 charge-balancing cations. This is corroborated by analyses of a quantitative ID ²⁷ A1 single-pulse direct-excitation spectra as shown in FIG. 6.

Concomitantly, the ^Al^ signal is diminished in intensity and is not detected in the 2D MQMAS spectrum of Cu-chabazite. The broad ²⁷A1^IV signal associated with the corresponding ion-exchange sites is thus reduced in intensity due to paramagnetic broadening and displacement of the ²⁷ A1 signals, while the intensity of the narrow ²⁷A1^IV signal remained almost unchanged indicating that the corresponding Na⁺ or H⁺ exchange sites are influenced to a lesser extent by the ion-exchange process. [0067] The presence of paramagnetic Cu²⁺ ions is expected to influence the ²⁷ A1 NMR signals due in part to hyperfme interactions of unpaired electrons associated with the Cu and proximate ²⁷ A1 species. Such paramagnetic interactions may result in broadening and displacement of ²⁷ A1 NMR signals, to the extent that the ²⁷ A1 NMR signals associated with ²⁷ A1 species very close (<0.5 nm) to paramagnetic centers are not expected to be detected by conventional NMR techniques. Additionally, ²⁷ A1 species at very distorted tetrahedral sites in zeolites exhibit exceptionally broad ²⁷ A1 NMR signals due to strong second-order quadrupolar interactions and also may not be detected by conventional direct-excitation NMR techniques.

[0068] The extent of such NMR-invisible species in the H- and Cu-chabazite materials is quantified by ID single-pulse direct-excitation ²⁷ A1 MAS NMR spectra and spin-counting analyses shown in FIG. 6. The percentage of NMR-invisible ²⁷ A1 species is determined by comparison to an AIN reference sample measured under the same conditions as an external spin-counting reference. In Na/H-chabazite 78% of the ²⁷ A1 species are at framework ²⁷A1^IV sites, while 17% are in the form of extraframework ²⁷A1^VI species. After steam aging at 750 °C, 37%, 7%, and 16% of all of the ²⁷ A1 species are in ²⁷A1^IV, ²⁷A1^V, and ²⁷A1^VI environments, respectively, with 40% of ²⁷ A1 not detected, presumably being in highly-distorted sites associated with large ²⁷ A1 quadrupolar couplings. This is consistent with substantial dealumination of the chabazite zeolite framework on steam-aging at 750 °C. After Cu- exchange, 68% and 7% of all ²⁷ A1 are in ²⁷A1^IV and ²⁷A1^VI environments, respectively, and 25% are not detected. This is consistent with removal of extraframework ²⁷A1^VI cations on ion-exchange as well as paramagnetic displacement and broadening reducing the extent of NMR-visible species. Notably, after steam-aging of Cu-chabazite at 750 °C, there is no change in the extent of NMR-invisible ²⁷ A1 species and little change in the detectable aluminum speciation, indicating that there is little or no dealumination of the material. The presence of Cu ions in the chabazite zeolite framework is thus directly shown to stabilize tetrahedral framework A1 atoms upon steam aging at temperatures of up to 750 °C.

Example 4 — Catalytic Methanol-to- Olefin (MTO) reaction properties of H- andH/Cu- chabazite forms of sample (SAR=20)

[0069] The catalytic properties of a chabazite sample having a SiOi/AhCb ratio (SAR) of 20: 1 (SAR=20), instead of an SAR=30 as in Example 1, was tested by monitoring the conversion of methanol to olefins. The experimental reactor setup was the same as in Example 1. Olefin product distribution was measured for a form of this sample that was Cu- exchanged, steam-aged (750 °C, 10% H2O, 6 h), subsequently back-exchanged with NH4⁺, and calcined to produce the H/Cu-form. A similar temperature program as that described in FIG. 1(b) was used for the MTO reaction test involving this sample, but here the temperature was raised to 330 °C to induce olefin production. This temperature was reached after 55 min on stream and was maintained until the end of the reported 120 min.

[0070] FIG. 9 shows the olefin selectivity in steam-aged Cu/H chabazite- (SAR=20). The reaction yields of ethene (dotted lines), propene (dashed lines), and butene (solid lines) are shown normalized to total maximum olefin production rate over the reported time period. The conversion of methanol to C₂-C₄ olefins as functions of temperature and time for the H-form and H/Cu-form of the sample are shown. Prior to reaching 330 °C, negligible production of olefins was observed. Upon reaching 330 °C, the H/Cu-form produced primarily C₂-C₄ olefins for the remainder of the time on stream. Notably, as compared to the sample with a SAR = 30, the H/Cu-form of the sample with a SAR = 20 produced more butene and less ethylene. The distribution of olefin products after 100 min on stream for the H/Cu-form of the sample was compared to the distribution of olefin products of the Cu/H-form of the sample with a SAR of 20 on a moles C₂-C₄ olefin per mole total olefins basis in Table 2.

Table 2 - Olefin mole fractions normalized with respect to total olefins in outlet at 100 min on-stream for steam-aged, Cu²⁺/H⁺ samples.

[0071] In FIGs 10(a) and 10(b) show the correlated ²⁹Si and ²⁷ A1 local bonding environments in H-CHA(SiO₂/AI₂O₃ =20). Both spectra were obtained at 9.4 T, 8 kHz magic-angle spinning, and 96 K. The 2D ²⁷Al{²⁹Si} D-HMQC spectrum of this sample shown in FIG. 10(a) establishes the presence of ²⁷ A1 atoms near framework ²⁹Si atoms. The spectrum shows a ²⁷A1^IV signal at 57 ppm correlated with ²⁹Si signals at -112, -106 and -100 ppm. The signal at -112 ppm corresponds to Q₄(2Al) and the signal at -106 ppm corresponds to Q₄(1A1). The signal at -100 ppm is assigned to Q₄(2Al) or Q₃(0A1) species. The 2D ²⁷Al{²⁹Si} J-HMQC spectrum of the H-chabazite sample shown in FIG. 10(b) establishes unambiguously the ²⁹Si atoms bonded to ²⁷ A1 atoms through a Si-O-Al linkage. This spectrum proves the identification of the ²⁹Si signal at -100 ppm as Q₄(2A1) Notably, these spectra demonstrate that the distribution of framework ²⁷ A1 atoms in this sample is different from the distribution of framework A1 atoms in the sample discussed in Examples 1- 3.

[0072] The preceding description sets forth numerous specific details such as examples of specific systems, components, methods, and so forth, in order to provide a good understanding of several embodiments of the present invention. It will be apparent to one skilled in the art, however, that at least some embodiments of the present invention may be practiced without these specific details. In other instances, well-known components or methods are not described in detail in order to avoid unnecessarily obscuring the present invention. Thus, the specific details set forth are exemplary. Particular embodiments may vary from these exemplary details and still be contemplated to be within the scope of the present invention.

[0073] Although the operations of the methods herein are described in a particular order, the order of the operations of each method may be altered so that certain operations may be performed in an inverse order or so that certain operation may be performed, at least in part, concurrently with other operations. In another embodiment, instructions or sub-operations of distinct operations may be in an intermittent and/or alternating manner.

[0074] It is to be understood that the above description is intended to be illustrative, and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reading and understanding the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

CLAIMS I/We claim:

1. A catalyst composition, comprising: a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

2. The catalyst composition of claim 1, comprising the alumina in an amount of about 2.0 wt% to about 25 wt%.

3. The catalyst composition of claim 1, wherein the SAR is about 10:1 to about 45:1, or about 30:1, or about 20:1.

4. The catalyst composition of claim 1, wherein the copper oxide is present in an amount of about 0.2 wt% to about 4.0 wt%.

5. The catalyst composition of claim 1, wherein the H/Cu-CHA zeolite is in the form of a powder, particles, pellets, extrudates, granules, beads or combinations thereof.

6. The catalyst composition of claim 5, wherein the catalyst composition is in the form of pellets or extrudates.

7. The catalyst composition of claim 6, wherein the pellets or extrudates are in the shape of at least one of a sphere, cylinder, cube or tetrahedron.

8. The catalyst composition of claims 6 or 7, wherein the pellets or extrudes have a diameter or width of about 0.1 mm to about 10 mm.

9. The catalyst composition of claim 1, further comprising a substrate, wherein the H/Cu-CHA zeolite is disposed on the substrate.

10. The catalyst composition of claim 9, wherein the substrate comprises a ceramic, a metal or a combination thereof.

11. The catalyst composition of claim 10, wherein the ceramic comprises at least one of cordierite, cordierite-alumina, silicon nitride, zircon mullite, spodumene, alumina-silica magnesia, zircon silicate, sillimanite, magnesium silicate, zircon, metalize, alpha-alumina, aluminosilicate or combinations thereof.

12. The catalyst composition of claim 10, wherein the metal comprises titanium, stainless steel, iron, nickel, chromium, aluminum, manganese, copper, vanadium, alloys thereof or combinations thereof.

13. The catalyst composition of claim 12, further comprising an oxide layer on a surface of the substrate.

14. The catalyst composition of any one of claims 9 to 13, wherein the substrate is a monolithic substrate, a corrugated sheet substrate, a wall-flow filter substrate or an open cell foam substrate.

15. The catalyst composition of claim 14, wherein the monolithic substrate comprises fine, parallel gas flow passages extending therethrough from an inlet to an outlet of the substrate.

16. The catalyst composition of any one of claims 9 to 13, wherein the H/Cu-CHA zeolite is disposed as a washcoat on a surface of the substrate.

17. The catalyst composition of any one of claims 9 to 13, wherein the substrate comprises a honeycomb structure.

18. The catalyst composition of claim 17, wherein gas flow passages of the honeycomb structure comprise at least one of a trapezoidal, rectangular, square, sinusoidal, hexagonal, oval or circular cross-section.

19. The catalyst composition of any one of claims 9 to 13, wherein the substrate comprises about 60 to about 400 gas flow passages.

20. The catalyst composition of claim 1, comprising a lifetime of about 30 min to about 12 hours when used to catalyze a methanol-to-olefm reaction at a reaction temperature of about 100 °C to about 600 °C.

21. The catalyst composition of claim 1, wherein performance of the H/Cu-CHA catalyst composition is not reduced in the presence of water.

22. A method of preparing a catalyst composition comprising a hydrogen/copper- chabazite (H/Cu-CHA) zeolite, the method comprising: preparing a copper-CHA (Cu-CHA) zeolite comprising copper oxide in an amount of about 0.1 wt% to about 5.0 wt%; steam-aging the Cu-CHA zeolite to re-distribute the Cu²⁺ ions and stabilize cages of the Cu-CHA zeolite and to prepare a steam-aged Cu-CHA zeolite; and preparing the H/Cu-CHA zeolite by back exchange of the steam-aged Cu-CHA zeolite with ammonium (NH₄ ⁺) ions, wherein the H/Cu-CHA zeolite comprises copper oxide in an amount of about 0.1 wt% to about 5.0 wt%.

23. The method of claim 22, wherein the H/Cu-CHA zeolite comprises silica (SiO₂) and about 2 wt% to about 25 wt% alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50:1.

24. The method of claim 22, wherein the H/Cu-CHA zeolite comprises the copper oxide in an amount of about 0.5 wt% to about 4.5 wt%.

25. The method of any one of claims 22 to 24, further comprising preparing a CHA zeolite and preparing the copper-CHA (Cu-CHA) zeolite from the CHA zeolite.

26. The method of claim 25, wherein preparing the CHA zeolite comprises preparing an ammonium chabazite (NH4⁺-CHA) zeolite.

27. The method of claim 25, wherein preparing the Cu-CHA zeolite comprises ion exchange of the CHA zeolite with Cu²⁺ ions.

28. The method of any one of claims 22 to 24, wherein preparing the Cu-CHA zeolite comprises mixing NH4⁺-CHA zeolite with a copper (II) sulfate solution to form a mixture.

29. The method of claim 28, further comprising adding nitric acid to the mixture to adjust pH to about 2.5 to about 4.5.

30. The method of claim 28, wherein the copper (II) sulfate solution is at a concentration of about 0.1 M to about 10.0 M.

31. The method of any one of claims 28, further comprising agitating the mixture at a temperature of about 70°C to about 90°C for about 30 minutes to about 2 hours.

32. The method of any one of claims 22 to 24, wherein the steam-aging is at a temperature of about 500 °C to about 1,000 °C.

33. The method of claim 32, wherein the Cu-CHA zeolite is in 10 wt% water for about 2 hours to about 16 hours.

34. The method of any one of claims 22 to 24, wherein preparing the H/Cu-CHA zeolite comprises, following the back-exchange, calcining in air at a temperature of about 300 °C to about 600 °C.

35. The method of claim 22, wherein the NH4⁺-CHA zeolite comprises silica and alumina at a silica-to-alumina ratio (SAR) of about 20: 1 to about 40: 1.

36. The method of claim 22, further comprising forming the H/Cu-CHA zeolite into a powder, particles, pellets, extrudates, granules, beads or combinations thereof.

37. The method of claim 36, wherein the catalyst composition is in the form of pellets or extrudates.

38. The method of claim 37, wherein the pellets or extrudates are in the shape of at least one of a sphere, cylinder, cube or tetrahedron.

39. The method of claims 37 or 38, wherein the pellets or extrudes have a diameter or width of about 0.1 mm to about 10 mm.

40. The method of claim 22, further comprising: depositing the H/Cu-CHA zeolite onto a substrate.

41. The method of claim 40, wherein the depositing comprises washcoating the H/Cu- CHA zeolite onto the substrate.

42. The method of claim 41, wherein the substrate comprises a ceramic, a metal or a combination thereof.

43. The method of claim 42, wherein the ceramic comprises cordierite, cordierite- alumina, silicon nitride, zircon mullite, spodumene, alumina-silica magnesia, zircon silicate, sillimanite, magnesium silicate, zircon, metalize, alpha-alumina, aluminosilicate or combinations thereof.

44. The method of claim 42, wherein the metal comprises titanium, stainless steel, iron, nickel, chromium, aluminum, manganese, copper, vanadium, alloys thereof or combinations thereof.

45. The method of any one of claims 40 to 44, wherein the substrate further comprises an oxide layer on a surface of the substrate.

46. The method of any one of claims 40 to 44, wherein the substrate is a monolithic substrate, a corrugated sheet substrate, a wall-flow filter substrate or an open cell foam substrate.

47. The method of claim 46, wherein the monolithic substrate comprises fine, parallel gas flow passages extending therethrough from an inlet to an outlet of the substrate.

48. The method of any one of claims 40 to 44, wherein the H/Cu-CHA zeolite is disposed as a washcoat on a surface of the substrate.

49. The method of any one of claims 40 to 44, wherein the substrate comprises a honeycomb structure.

50. The method of claim 49, wherein gas flow passages of the honeycomb structure comprise at least one of a trapezoidal, rectangular, square, sinusoidal, hexagonal, oval or circular cross-section.

51. The method of claim 40, wherein the substrate comprises about 60 to about 400 gas flow passages.

52. A method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze a methanol-to-olefm (MTO) reaction, the method comprising: converting MTO in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 10: 1 to about 45: 1, or about 30:1, or about 20: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

53. The method of claim 52, wherein the converting is at a temperature of about 100 °C to about 600 °C.

54. The method of claim 52 or 53, wherein the catalyst composition has a lifetime of about 30 min to about 400 min.

55. The method of claim 52 or 53, wherein the catalyst composition is resistant to hydrothermal degradation.

56. The method of claim 52 or 53, wherein converting the MTO comprises flowing methanol vapor, optionally in a carrier gas, over the catalyst composition.

57. The method of claim 56, wherein the carrier gas comprises argon, helium or combinations thereof.

58. The method of claim 52, wherein the catalyst composition is in a packed-bed reactor or a fluidized bed reactor.

59. The method of claim 58, wherein the packed-bed reactor is at a temperature of about 100 °C to about 600 °C.

60. The method of claim 52, wherein the catalyst composition has an olefin selectivity of at least about 0.1 to about 0.4.

61. The method of claim 52, wherein the catalyst composition has an ethylene selectivity of at least about 0.35.

62. The method of claim 52, wherein the catalyst composition has an propylene selectivity of at least about 0.35.

63. The method of claim 52, wherein the H/Cu-CHA catalyst composition has an olefin yield of about 10 wt% to about 30 wt% greater than a comparative H-CHA catalyst composition or a comparative H-CHA catalyst composition that has been steam aged.

64. A method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze an ethanol-to-ethylene reaction, the method comprising: converting ethanol to ethylene in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

65. A method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite in a selectoforming process to catalyze shape-selective cracking of short linear alkanes to increase octane number of light naphtha, the method comprising: operating the selectoforming process in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

66. A method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to synthesize methylamines, the method comprising: synthesizing methylamines in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

67. A method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze ethanol dehydration, the method comprising: performing an ethanol dehydration process in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

68. A method of using a catalyst composition comprising a hydrogen/copper-chabazite (H/Cu-CHA) zeolite to catalyze an ethylene oligomerization-cracking process, the method comprising: performing an ethylene oligomerization-cracking process in the presence of the catalyst composition, wherein the H-CHA zeolite comprises a hydrogen/copper-chabazite (H/Cu-CHA) zeolite comprising silica (SiO₂) and alumina (AI₂O₃) at a silica-alumina ratio (SAR) of about 5: 1 to about 50: 1 and about 0.1 wt% to about 5.0 wt% of a copper oxide.

69. The catalyst composition of claim 1, wherein the catalyst composition is adapted for conversion of methanol-to-olefms.

70. The catalyst composition of claim 1, wherein the form of the H/Cu-CHA zeolite is suitable for use in a packed bed reactor for a methanol-to-olefm conversion process.