Ferrosilicate MTW molecular sieves and their synthesis and use

Abstract

The invention relates to an MTW framework topological structure iron silicate molecular sieve, and synthesis and application thereof. The 1, 3-diisobutylimidazole cation can be used as a structure-directing agent to directly prepare the iron silicate MTW. Ferrosilicate MTWs are useful in organic compound conversion and absorption processes.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. application No. 18 / 165,387, filed February 7, 2023, the disclosure of which is incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a ferrosilicate molecular sieve with an MTW framework topology, its synthesis, and its use as an adsorbent and a catalyst for organic compound conversion reactions (particularly hydrocarbon conversion reactions). Background Art

[0004] Molecular sieve materials are classified by the International Zeolite Association (IZA) Structure Commission according to the IUPAC Commission for Zeolite Nomenclature. Based on this classification, framework zeolites and other crystalline microporous materials of defined structure are assigned a three-letter code and described in the Zeolite Structure Database maintained by IZA (www.iza-structure.org / databases / ).

[0005] One known, structurally defined molecular sieve is the material designated MTW, which is a molecular sieve having a unique one-dimensional system of 12-membered (12-MR) ring pores. Examples of MTW framework-type molecular sieves include CZH-5, NU-13, Theta-3, TPZ-12, and ZSM-12. The aluminosilicate ZSM-12 is commercially important because it is active as a shape-selective acid catalyst in industrial hydrocarbon conversion processes such as the alkylation and disproportionation of aromatics, the hydroisomerization of linear alkanes, and the cracking of hydrocarbons.

[0006] While the one-dimensional pore system provides the aluminosilicate ZSM-12 with unique shape selectivity, it also leads to significant diffusion restrictions for reactants and products. For chemical reactions where diffusion is critical, the smaller crystal size provides shorter diffusion paths, thereby enhancing mass transport and improving the desired reaction pathways, which has a positive impact on the selectivity and conversion of such reactions.

[0007] For acid catalysis, the molar ratio of silica to alumina is an important chemical property of the molecular sieve. While high acidity is generally beneficial for overall catalytic activity, the presence of Brønsted acid sites (e.g., those formed on framework Al atoms) can catalyze secondary reactions that are detrimental to the desired chemical reaction. For example, hydroisomerization of linear alkanes with aluminosilicate ZSM-12 can result in undesirable overcracking, thereby reducing the yield of the isomerized alkanes. One strategy to overcome the acidity limitation is to reduce the acidity by isomorphously replacing framework Al atoms with metal atoms with lower acid strength than Al. Current synthesis methods for Al-free ZSM-12 generally rely on post-synthesis modification of aluminosilicate ZSM-12. These methods include high-temperature digestion or acid treatment to partially remove Al from the framework sites and generate empty silanol nests ([SiOH]4) defects that can be replaced with the desired metal atoms. However, a large amount of framework Al may remain and may adversely affect many related reactions, potentially leading to significant reductions in yield and selectivity.

[0008] Therefore, there is a continuing need for molecular sieve materials of MTW framework topology with improved properties, particularly in terms of catalytic properties for various applications, in particular for hydrocarbon conversion reactions, such as the isomerization of linear alkanes.

[0009] According to the present disclosure, ferrosilicate molecular sieves with an MTW framework topology can be directly synthesized using 1,3-diisobutylimidazolium cation as a structure-directing agent, and in some cases, it was found that small crystalline molecular sieves can be produced. Summary of the Invention

[0010] In one aspect, a ferrosilicate molecular sieve having an MTW framework topology and a d50 crystal size of 0.5 microns or less is provided.

[0011] In another aspect, a method for producing a ferrosilicate molecular sieve having an MTW framework topology is provided. The method comprises: (1) forming a reaction mixture comprising: (a) an iron source; (b) a silicon source; (c) an alkali metal [M] source; (d) a structure directing agent [Q] comprising a 1,3-diisobutylimidazolium cation; (e) a hydroxide ion source; and (f) water; and (2) subjecting the reaction mixture to crystallization conditions sufficient to form ferrosilicate molecular sieve crystals.

[0012] In yet another aspect, a method is provided for converting a feedstock comprising an organic compound into a conversion product, the method comprising contacting the feedstock with a catalyst under organic compound conversion conditions, the catalyst comprising a ferrosilicate molecular sieve of MTW framework topology having a d50 crystal size of 0.5 microns or less. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1A scanning electron micrograph (SEM) image of the as-produced ferrosilicate MTW product of Example 1 is shown.

[0014] Figure 2 Powder X-ray diffraction (XRD) patterns of the as-made ferrosilicate MTW (top) and calcined ferrosilicate MTW (bottom) materials of Example 1 are shown.

[0015] Figure 3 This is a graph showing the change in n-decane conversion over the ferrosilicate MTW catalyst of Example 3 as a function of temperature. DETAILED DESCRIPTION

[0016] definition

[0017] The term "ferrosilicate" means a molecular sieve having a framework composed of repeating FeO4 and SiO4 tetrahedral units.

[0018] The term "MTW" refers to the MTW type topology or framework recognized by the International Zeolite Association (IZA) Structure Commission, and the term "MTW molecular sieve" means a crystalline microporous material in which the major crystalline phase is MTW.

[0019] The term "as-made" refers to the molecular sieve in its form after crystallization and prior to removal of the structure directing agent.

[0020] The term "extra-framework metal" refers to metals that are present on the surface and / or within the cages and / or pores of the molecular sieve and do not include atoms that constitute the molecular sieve framework.

[0021] The term "Cn" hydrocarbons refers to hydrocarbon compounds having n carbon atoms per molecule. The term "Cn+" hydrocarbons refers to hydrocarbon compounds having n or more carbon atoms per molecule. The term "Cn-" hydrocarbons refers to hydrocarbon compounds having no more than n carbon atoms per molecule.

[0022] Synthesis of molecular sieves

[0023] Ferrosilicate molecular sieves with MTW framework topology can be synthesized by: (1) forming a reaction mixture comprising: (a) an iron source; (b) a silicon source; (c) an alkali metal [M] source; (d) a structure directing agent [Q] comprising a 1,3-diisobutylimidazolium cation; (e) a hydroxide ion source; and (f) water; and (2) subjecting the reaction mixture to crystallization conditions sufficient to form ferrosilicate molecular sieve crystals.

[0024] The reaction mixture may have a composition in molar ratios within the ranges listed in Table 1:

[0025] Table 1

[0026] The most extensive secondary <![CDATA[SiO2 / Fe2O3]]> 50 to 500 75 to 250 <![CDATA[M2O / SiO2]]> 0.01 to 0.50 0.01 to 0.30 <![CDATA[Q / SiO2]]> 0.05 to 0.50 0.10 to 0.30 <![CDATA[OH / SiO2]]> 0.05 to 1.00 0.10 to 0.60 <![CDATA[H2O / SiO2]]> 5 to 80 10 to 50

[0027] wherein M is an alkali metal, and Q represents a 1,3-diisobutylimidazolium cation.

[0028] Suitable iron sources include iron (III) salts. In some respects, organic iron (III) salts can be used, such as iron acetate (III), iron citrate (III) and iron oxalate (III). In some respects, inorganic iron (III) salts can be used, such as iron halide (III), iron nitrate (III) and iron sulfate (III). If desired, the combination of two or more different iron (III) salts can be used. In particular, iron (III) salt can be iron nitrate (III) and / or iron sulfate (III).

[0029] Suitable silicon sources include colloidal silica, precipitated silica, fumed silica, alkali metal silicates, tetraalkyl orthosilicates (eg, tetraethyl orthosilicate), and any combination thereof.

[0030] The alkali metal [M] may be lithium, sodium, potassium, rubidium, cesium or any combination thereof. The alkali metal is preferably sodium or potassium, preferably sodium. Suitable alkali metal sources include alkali metal hydroxides such as sodium hydroxide or potassium hydroxide.

[0031] The structure directing agent (Q) comprises a 1,3-diisobutylimidazolium cation represented by the following structure (1):

[0032]

[0033] Suitable sources of Q include hydroxides, chlorides, bromides and / or other salts of quaternary ammonium compounds.

[0034] The reaction mixture may also contain seed crystals from a previously synthesized crystalline molecular sieve material, such as a crystalline molecular sieve with an MTW framework topology. The amount of seed crystals is not particularly limited and typically corresponds to 0.1 to 25 wt % (e.g., 0.1 to 10 wt %) of the total weight of silica in the reaction mixture. Adding seed crystals can be beneficial in reducing the time required for complete crystallization and / or minimizing the formation of other crystalline impurities.

[0035] The reaction mixture components may be supplied by more than one source. In addition, two or more reaction mixture components may be provided by one source.

[0036] The reaction mixture can be prepared by any conceivable means, wherein mixing by agitation is preferred, preferably by stirring.The reaction mixture can be prepared in batch, continuous or semi-continuous mode.

[0037] The reaction mixture may be in the form of a solution, a colloidal dispersion (colloidal solution), a gel or a paste, with gels being preferred.

[0038] Crystallization and post-synthesis processing

[0039] Crystallization of the molecular sieve from the reaction mixture can be carried out under static or stirred conditions in a suitable reactor vessel such as a polypropylene can or a Teflon-lined or stainless steel autoclave placed in a convection oven maintained at a temperature of 100° C. to 200° C. for a time sufficient for crystallization to occur (e.g., about 1 day to 21 days or about 1 day to 10 days). Preferably, crystallization is carried out under autogenous pressure, preferably in an autoclave.

[0040] Once the desired molecular sieve crystals are formed, the solid product can be separated from the reaction mixture by standard mechanical separation techniques (such as centrifugation or filtration). The recovered crystals are washed with water and then dried for a few seconds to a few minutes (e.g., 5 seconds to 10 minutes for rapid drying) or a few hours (e.g., 4 hours to 24 hours for oven drying at 75°C to 150°C) to obtain the molecular sieve crystals as prepared. The drying step can be carried out under vacuum or atmospheric pressure.

[0041] As a result of the crystallization process, the recovered crystalline molecular sieve product contains within its pores at least a portion of the structure directing agent used in the synthesis.

[0042] The prepared molecular sieve may be further subjected to heat treatment, ozone treatment or other treatment to remove all or part of the structure directing agent used in its synthesis. The heat treatment (e.g., calcination) can be carried out in any conventional manner known in the art. For example, the prepared molecular sieve can be calcined at a temperature of 300° C. to 800° C. (e.g., 400° C. to 650° C.) for a period of time in the range of 1 hour to 10 hours (e.g., 3 hours to 6 hours). In addition, calcination is typically carried out in an oxygen-containing atmosphere, such as air or an oxygen atmosphere.

[0043] The molecular sieve synthesized by the method includes one or more extra-framework alkali metal cations (e.g., Na + ). Generally, it is desirable to remove the extra-framework alkali metal cations from the molecular sieve by ion exchange or other known techniques and replace them with hydrogen, ammonium or any desired metal ion. Particularly preferred cations are those that modulate the catalytic activity of certain hydrocarbon conversion reactions. These cations include hydrogen, rare earth metals, and metals from Groups 2 to 15 of the Periodic Table of Elements. The amount of metal may be in the range of 0.001 to 20 wt % (e.g., 0.01 to 10 wt %, or 0.1 to 5.0 wt %) of the catalyst.

[0044] Characterization of molecular sieves

[0045] The ferrosilicate MTW molecular sieve synthesized by the methods described herein can have a SiO2 / Fe2O3 molar ratio of at least 50 (e.g., 50 to 500, or 50 to 250, or 50 to 125, or 75 to 500, or 75 to 250, or 75 to 125). The SiO2 / Fe2O3 molar ratio of the molecular sieve can be determined by conventional analysis.

[0046] The synthesis method described herein can produce ferrosilicate MTW crystals with high purity, and preferably pure phase. As used herein, the term "pure phase" means that the ferrosilicate MTW molecular sieve composition can contain at least 95% by weight (e.g., at least 97% by weight or at least 99% by weight) of a molecular sieve with an MTW topology structure based on the total weight of the composition, as determined by powder XRD or NMR or other known measurement methods for such determinations. The remainder of the composition is non-MTW material, which may include amorphous material, different crystalline phases, different framework types, or any combination thereof.

[0047] Crystals of ferrosilicate MTW molecular sieve produced according to the methods described herein may be uniform, with little or no twinning and / or multiple twinning, or may form agglomerates.

[0048] The ferrosilicate MTW molecular sieve prepared as described herein may have a smaller crystal size. The ferrosilicate MTW molecular sieve crystals may have a d50 crystal size of 0.5 microns or less (e.g., 0.2 microns or less, or 0.1 microns or less, or 0.05 to 0.5 microns, 0.05 to 0.1 microns, or 0.1 to 0.25 microns). More preferably, the ferrosilicate MTW molecular sieve crystals have a d90 crystal size of 0.5 microns or less (e.g., 0.2 microns or less, or 0.1 microns or less, or 0.05 to 0.5 microns, or 0.05 to 0.1 microns, or 0.1 to 0.25 microns). The ferrosilicate MTW crystals may have d50 and d90 values ​​as described above.

[0049] Crystal size depends on individual crystals. Crystal size is the length of the longest diagonal of a three-dimensional crystal. Direct measurements of crystal size can be performed using microscopic methods such as SEM and TEM. For example, measurements by SEM involve examining the morphology of the material at high magnifications (typically 1000× to 100,000×). The SEM method can be performed as follows: a representative portion of the molecular sieve powder is distributed in a suitable amount so that individual particles are reasonably evenly dispersed throughout the field of view at 1000× to 100,000× magnifications. From this population, a statistically significant sample of random individual crystals (e.g., 50-200) is inspected, and the longest diagonal of the individual crystals is measured and recorded. (Particles that are clearly large polycrystalline aggregates should not be included in the measurement). Based on these measurements, the d50 and d90 of the sample crystal size are calculated.

[0050] The ferrosilicate MTW molecular sieve synthesized as described herein is characterized by its powder XRD pattern. Representative powder XRD patterns of MTW molecular sieves can be found in "Collection of Simulated XRD Powder Patterns for Zeolites" by MMJ Treacy and JB Higgins (Elsevier, fifth revised edition, 2007).

[0051] The powder X-ray diffraction data reported here were collected using standard techniques using copper K-alpha radiation. Minor changes in the diffraction pattern may be due to changes in the lattice constant caused by variations in the molar ratio of the framework species for a particular sample. In addition, sufficiently small crystals will affect the shape and intensity of the peaks, resulting in significant peak broadening. Minor changes in the diffraction pattern may also be caused by variations in the organic compounds used in the preparation. Calcination may also result in minor changes in the XRD pattern. Despite these minor perturbations, the basic lattice structure remains unchanged.

[0052] Application of Ferrosilicate MTW Molecular Sieve

[0053] Ferrosilicate MTW molecular sieves (in which some or all of the structure directing agents are removed) can be used as adsorbents or catalysts to catalyze a variety of organic compound conversion processes. Examples of chemical conversion processes that are effectively catalyzed by the ferrosilicate MTW molecular sieves described herein, alone or in combination with one or more other catalytically active materials (including other crystalline catalysts), include those that require catalysts with acid activity. Examples of organic conversion processes that can be catalyzed by the ferrosilicate MTW molecular sieves described herein include cracking, hydrocracking, disproportionation, alkylation, oligomerization, and isomerization.

[0054] Ferrosilicate MTW molecular sieves (wherein some or all of the structure directing agent is removed) can be used in combination with another material that can withstand the temperature and other conditions used in the organic conversion process. Such resistant materials can be selected from active materials, inactive materials, synthetic zeolites, natural zeolites, inorganic materials, or mixtures thereof. Examples of such resistant materials can be selected from clays, silica, metal oxides (e.g., alumina), or mixtures thereof. The inorganic material can be naturally occurring or in the form of a gelatinous precipitate or gel, including a mixture of silica and metal oxides. Resistant materials used in combination with ferrosilicate MTW molecular sieves (i.e., combined with them or present during the synthesis of the as-prepared ferrosilicate MTW molecular sieve crystals, which are active) tend to alter the conversion rate and / or selectivity of the catalyst in certain organic conversion processes. Inactive resistant materials are suitable for use as diluents to control the amount of conversion in a given process, so that the product can be obtained in an economical and orderly manner without resorting to other means for controlling the reaction rate. These materials can be incorporated into naturally occurring clays (e.g., bentonite and kaolin) to improve the crushing strength of the catalyst under commercial operating conditions. The inactive, resistant material (ie, clay, oxide, etc.) acts as a binder for the catalyst.A catalyst having good crush strength is beneficial because it is desirable to prevent the catalyst from breaking down into a powdery material in commercial use.

[0055] Naturally occurring clays that can be composited with the ferrosilicate MTW molecular sieve include the montmorillonite and kaolin families, which include sub-bentonites and kaolins commonly known as Dixie, McNamee, Georgia, and Florida clays, or other kaolins, wherein the primary mineral components are halloysite, kaolinite, dickite, nacrite, or silica-rich kaolinite. Such clays can be used in their original state as mined or initially subjected to calcination, acid treatment, or chemical modification. Binders that can be composited with the ferrosilicate molecular sieve MTW also include inorganic oxides selected from silica, zirconium oxide, titanium oxide, magnesium oxide, beryllium oxide, aluminum oxide, or mixtures thereof.

[0056] Ferrosilicate MTW molecular sieves (in which some or all of the structure directing agent is removed) can be composited with porous matrix materials such as silica-alumina, silica-magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania, and ternary compositions such as silica-alumina-thoria, silica-alumina-zirconia, silica-alumina-magnesia, and silica-magnesia-zirconia.

[0057] The relative proportions of the ferrosilicate MTW molecular sieve and the inorganic oxide matrix can vary widely, with the ferrosilicate MTW content ranging from 1 to 90 wt % (eg, 2 to 80 wt %) of the composite material.

[0058] Example

[0059] The following illustrative examples are intended to be non-limiting.

[0060] Example 1

[0061] Synthesis of Ferrosilicate MTW Molecular Sieve

[0062] 0.62 g of deionized water, 1.68 g of NaOH solution (1 M), and 7.26 g of 1,3-diisobutylimidazolium hydroxide solution (9 wt.%) were added to a polytetrafluoroethylene liner and the solution was stirred until homogeneous. 1.00 g of fumed silica was then added and the mixture was stirred until homogeneous. Finally, 0.14 g of iron (III) nitrate nonahydrate was added. The final molar ratio of the gel was 1 SiO2:0.01 Fe2O3:0.1 NaOH:0.2 1,3-diisobutylimidazolium hydroxide:30 H2O. The liner was placed in a stainless steel autoclave and rotated in an oven at 150°C for 7 days. The solid product was filtered, washed with excess deionized water, and dried in an oven at 95°C.

[0063] The SEM images of the manufactured products are shown in Figure 1 shown.

[0064] The as-fabricated material was calcined in flowing air to 550°C for 5 hours using a standard calcination protocol to remove the organic structure directing agent [Q].

[0065] Figure 2 Powder XRD patterns of the as-prepared and calcined products are shown, confirming that the synthesized material is MTW.

[0066] The calcined material is then ion-exchanged to the NH4 form by heating in an ammonium nitrate solution (typically 1 g NH4NO3 / 1 g molecular sieve in 10 mL deionized water at 95°C for at least 2 hours). The molecular sieve is then filtered. This is repeated twice, for a total of three exchanges. Finally, the molecular sieve is washed with deionized water to a conductivity of less than 50 μS / cm and dried in air at 95°C. The resulting NH4 molecular sieve is converted to the H form by calcination using a standard calcination protocol.

[0067] Analysis by temperature-programmed desorption of n-propylamine showed that the product had 258 μmol H + / g of acid site density.

[0068] Analysis by inductively coupled plasma atomic emission spectroscopy (ICP-AES) showed that the product had a SiO2 / Fe2O3 molar ratio of 90.

[0069] Example 2

[0070] Constraint Index Test

[0071] The Constraint Index (CI) is a test that describes the relative propensity of a material to crack straight-chain versus branched alkanes. The competitive cracking of n-hexane and 3-methylpentane was first described by VJ Frillette et al. (J. Catal. 1981, 67, 218-222).

[0072] The calcined ferrosilicate MTW product (H type) described in Example 1 was pelletized at 5 kpsi, crushed and made into 20-40 mesh granules. A 0.6 g sample of the granular material was calcined in air at 540°C for 4 hours and cooled in a desiccator to ensure dryness. Next, 0.47 g of the material was filled into 1 The reactor was heated in a 4-inch stainless steel tube with alundum on both sides of the molecular sieve bed. A furnace (Applied Test Systems, Inc.) was used to heat the reactor tube. Nitrogen was introduced into the reactor tube at 9.4 mL / min under atmospheric pressure. The reactor was heated to approximately 900°F (482°C) and a 50 / 50 feed of n-hexane / 3-methylpentane was introduced into the reactor at a rate of 8 μL / min. The feed was delivered by an ISCO pump. After 15 minutes of feed introduction, direct sampling into the GC was begun.

[0073] The ferrosilicate MTW catalyst exhibited a CI value of 1.

[0074] Example 3

[0075] Hydrogenation conversion of n-decane

[0076] The calcined ferrosilicate MTW product described in Example 1 (NH4 form) was impregnated with palladium at a loading of 0.5 wt.% using the required amount of tetraammine palladium (II) nitrate dissolved in deionized water. The impregnated sample was washed to a conductivity of less than 50 μS / cm, dried, and calcined in air at 482°C for 3 hours. The resulting powdered catalyst material was pelletized at 5 kpsi, crushed, and sieved to 20-40 mesh.

[0077] 0.5 g of catalyst was loaded into a 23-inch long × 1 The reactor was placed in the center of a 4-inch outer diameter stainless steel reaction tube and loaded with corundum upstream of the catalyst for preheating the feed. The operating conditions were as follows: total pressure of 1200 psig; a downflow hydrogen rate of 8.3 mL / min when measured at 1 atmosphere and 25°C; and a downflow n-decane feed rate of 0.66 cm 3 All materials were first reduced in flowing hydrogen at approximately 315° C. for 1 hour. Products were analyzed every 30 minutes by online capillary gas chromatography (GC). Raw data from the GC were collected by an automated data collection / processing system, and hydrocarbon conversion was calculated from the raw data.

[0078] Conversion is defined as the amount of n-decane that reacts to produce other products, including iso-C10. Yields are expressed as mol% of products other than n-decane and include the iso-C10 isomer as a yield product.

[0079] The results of n-decane hydrogenation conversion are as follows Figure 3 The results show that the ferrosilicate MTW catalyst has high selectivity for the isomerization of linear alkanes.

Claims

1. A ferrosilicate molecular sieve with an MTW framework topology having a d50 crystal size of 0.5 μm or less.

2. The ferrosilicate molecular sieve according to claim 1, wherein the SiO2 / Fe2O3 molar ratio is 50 to 500.

3. The ferrosilicate molecular sieve according to claim 1, wherein the SiO2 / Fe2O3 molar ratio is 75 to 125.

4. The ferrosilicate molecular sieve of claim 1, having a d50 crystal size of 0.05 to 0.25 microns and a d90 crystal size of less than 0.5 microns.

5. A method for preparing a ferrosilicate molecular sieve having an MTW framework topology, the method comprising: (1) forming a reaction mixture, the reaction mixture comprising: (a) Iron source; (b) silicon source; (c) an alkali metal [M] source; (d) a structure directing agent [Q] comprising a 1,3-diisobutylimidazolium cation; (e) a source of hydroxide ions; and (f) water; and (2) subjecting the reaction mixture to crystallization conditions sufficient to form crystals of the ferrosilicate molecular sieve.

6. The method of claim 5, wherein the iron source comprises an iron (III) salt.

7. The method of claim 5, wherein the iron (III) salt is selected from the group consisting of iron (III) nitrate, iron (III) sulfate, and any combination thereof.

8. The method of claim 5, wherein the silicon source is selected from the group consisting of colloidal silica, precipitated silica, fumed silica, alkali metal silicates, tetraalkyl orthosilicates, and any combination thereof.

9. The method of claim 5, wherein the alkali metal comprises sodium.

10. The method of claim 5, wherein the crystallization conditions comprise heating the reaction mixture at a temperature in the range of 100°C to 200°C under autogenous pressure.

11. The method of claim 5, wherein the reaction mixture has the following composition in molar ratio:

12. The method of claim 5, wherein the reaction mixture has the following composition in molar ratio:

13. A method of converting a feedstock comprising an organic compound into a conversion product, the method comprising contacting the feedstock with a catalyst under organic compound conversion conditions, the catalyst comprising the ferrosilicate molecular sieve of claim 1.

14. The process of claim 13, wherein the conversion process is at least one of a cracking process, a hydrocracking process, a disproportionation process, an alkylation process, or an isomerization process.

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