KR20180112072A - Liquid phase transalkylation method - Google Patents

Abstract

The present invention provides catalytic methods and corresponding catalysts for the transalkylation, e.g., transalkylation, of 1-ring (C ₉₊ ) aromatic compounds to form para-xylene and / or other xylenes. Suitable catalysts include molecular sieves having a 3-D 12-membered ring skeleton structure, molecular sieves having a 1-D 12-membered ring skeleton structure, acidic microporous materials having a pore channel size of at least 6.0 Angstroms, and / or MWW skeletal structures Containing molecular sieve. The method includes performing transalkylation wherein at least a portion of the feed to the transalkylation process is in the liquid phase. Optionally, the transalkylation conditions may correspond to conditions in which the continuous liquid phase is present in the reaction environment. Some embodiments include a liquid phase transalkylation process for a naphthalene-containing feedstock stream.

Description

Liquid phase transalkylation method

preference

This application claims priority from U.S. Provisional Application No. 62 / 313,966, filed March 28, 2016, and European Application No. 16170265.9, filed May 19, 2016, each of which is hereby incorporated by reference in its entirety.

Technical field

Systems and methods are provided for transalkylation of aromatic compounds, such as transalkylation of mononuclear aromatic compounds.

The preparation of xylene from mixed aromatic streams is a commercially important process. Because of the various equilibria, aromatization processes tend to produce relatively small amounts of xylene relative to other single ring aromatics. One option for converting the aromatic feed to produce additional xylenes is to perform the transalkylation process. Conventional transalkylation processes are usually carried out under gaseous conditions including temperatures of at least about 380 ° C.

U.S. Patent No. 7,553,791 is, C ₉₊ The resulting product was converted to the feedstock containing the aromatic hydrocarbon containing a rigid aromatic product and the resulting product, by weight of the C ₈ aromatic fraction of less than about 0.5% by weight of ethylbenzene (I) an acidic component having an alpha value of at least 300; And (ii) contacting the feedstock with a catalyst composition comprising a hydrogenation component having a hydrogenation activity of at least 300 (the ratio of ethylene to ethane in the transalkylation product under defined conditions) to produce a _{C9 +} Converting the aromatic hydrocarbons to a reaction product containing xylene is taught. Preferably, the aromatic product contains less than about 0.3% by weight ethylbenzene, based on the weight of the C ₈ aromatic fraction of the resulting product. More preferably, the aromatic product contains ethylbenzene of less than about 0.2% by weight, based on the weight of the C ₈ aromatic fraction of the resulting product. Preferably, the acidic component comprises a first molecular sieve having an MTW structure, a molecular sieve having a MOR structure, and a d-maximum interval (A) at 12.4 + - 0.25, 6.9 + - 0.15, 3.57 + - 0.07 and 3.42 + 0.07 And a porous crystalline inorganic oxide material having an X-ray diffraction pattern. More preferably, the catalyst comprises molecular sieve ZSM-12. Alternatively, the porous crystalline inorganic oxide material is selected from the group consisting of one or more of MCM-22, PSH-3, SSZ-25, MCM-36, MCM-49 and MCM-56. In another embodiment, the catalyst comprises a second molecular sieve having a constraint index in the range of 3-12. Preferably, the second molecular sieve is ZSM-5. Preferably, the catalyst comprises two molecular sieves, wherein the first molecular sieve is ZSM-12 and the second molecular sieve is ZSM-5. Conveniently, the catalyst composition is a particulate, and the first and second molecular sieves are each contained in the same catalyst particle. Preferably, the hydrogenation component is selected from the group consisting of at least one of Group VIIB and Group VIIB metals. More preferably, the hydrogenation component is selected from the group consisting of at least one of rhenium, platinum and palladium.

A catalyst system for the transalkylation of C ₉₊ aromatics is disclosed in U.S. Patent No. 7,663,010. The catalyst system described above comprises (a) a molecular sieve having a constraint index in the range of 3-12 (e.g. 10 MR molecular sieves such as ZSM-5, ZSM-11, ZSM-22 and ZSM-23) A first catalyst comprising a metal promoting saturation of the olefin formed by the first catalyst; And (b) molecular sieves having a constraint index in the range of less than 3 (e.g., 12 MR molecular sieves such as ZSM-12, MOR, zeolite beta, MCM-22 family molecular sieves) And a second catalyst comprising a metal that may be different. U.S. Patent Nos. 8,163,966 and 9,034,780 describe additional catalyst systems and methods of performing transalkylation on mixed aromatic feeds.

Traditionally, the transalkylation process was carried out under gas phase transalkylation conditions. However, it is desirable to perform transalkylation at least partially on the liquid phase feed to minimize energy consumption.

At least some embodiments disclosed herein relate, at least in part, to performing transalkylation under liquid phase conditions. At least in part performed transalkylation on the feed liquid, further allows for improved catalyst life and / or increased selectivity in the reaction conditions of lower severity for the production of an aromatic having a desired number of carbon (for example, C ₈ aromatic) of. Other potential advantages of performing transalkylation under liquid phase conditions may include at least one of lower reaction temperature, reduced or minimized energy consumption, reduced or minimized byproduct formation, and / or improved C ₈ aromatic yield.

In an embodiment, a liquid phase transalkylation process of an aromatic compound is provided. The method comprises exposing the transalkylation catalyst to an aromatic feedstock comprising at least one of benzene and toluene and a C ₉₊ aromatic under transalkylation conditions effective to produce a transalkylation effluent. The molar fraction of aromatic compounds in the liquid phase in the feedstock relative to the total amount of aromatic compounds in the feedstock is at least about 0.01 under effective transalkylation conditions. The presence of a liquid mole fraction in a transalkylation reaction environment allows for enhanced and / or modified transalkylation activity relative to gas phase transalkylation conditions. The resulting transalkylation effluent has a higher C ₈ aromatics weight percentage than the feedstock.

The transalkylation catalyst may be a molecular sieve having a three-dimensional 12-membered ring or higher pore network; A molecular sieve having a one-dimensional, 12-membered ring or more pore network, wherein the one-dimensional channel has a pore channel size of at least 6.0 Angstroms; An acidic microporous material having a pore channel size of at least 6.0 Angstroms; And a molecular sieve having an MWW framework. Optionally, the catalyst may further comprise from 0.01% to 5.0% by weight of a Group 6-11 metal such as Pd, Pt, Ni, Rh, Cu, Sn or combinations thereof. In embodiments where the catalyst comprises a molecular sieve having a MWW framework, the catalyst may optionally include from 0.01% to 5.0% by weight of an 8-10-group noble metal such as Pd. Optionally, the Group 6-11 metal or group 8-10 metal may correspond to a bimetallic metal.

Figure 1 shows an example of the mole fraction of the liquid feed at various temperature and pressure conditions.
Figure 2 shows the feed conversion and the xylene yield of the transalkylation with the mordenite catalyst.
Figure 3 shows feed conversion and Xylene yield of transalkylation by MCM-22 catalyst.
Figure 4 shows feed conversion and xylene yield of transalkylation with 0.15 wt% Pd / FAU catalyst.
Figure 5 shows the feed conversion and xylene yield of transalkylation with MCM-49 catalyst.
Figure 6 shows the xylene yield of transalkylation with MCM-49 catalyst.
Figure 7 shows the xylene yield of transalkylation with a 0.15 wt% Pd / MCM-49 catalyst.
Figure 8 shows the xylene yield of transalkylation by zeolite beta catalyst.
Figure 9 shows the xylene yield of transalkylation with a 0.15 wt% Pd / zeolite beta catalyst.
Figure 10 shows the xylene yield of transalkylation with a high Si / Al ₂ ratio zeolite beta catalyst.
Figure 11 shows the xylene yield of transalkylation by FAU catalyst.
Figure 12 shows the xylene yield of the transalkylation by the various catalysts used in Figures 6-11.
Figure 13 shows the xylene yield and benzene yield of the transalkylation by various catalysts used in Figures 6-11.
Figure 14 shows the production of a heavy aromatics (C ₁₀₊ ) from transalkylation by various catalysts used in Figures 6-11.
Figure 15 shows the results from the transalkylation of naphthalene in the presence of MCM-22 by various feedstocks.
Figure 16 shows the additional xylene yield results for MCM-49 and 0.15 wt% Pd / MCM-49.
Figure 17 shows the naphthalene conversion over time during transalkylation of the naphthalene containing feedstock.

Overview and Definitions

In various embodiments, methods of transalkylating a 1-ring (C ₉₊ ) aromatic compound to form para-xylene and / or other xylenes and corresponding catalysts are provided. The method includes performing transalkylation when at least a portion of the feed to the transalkylation process is in a liquid phase. Optionally, the transalkylation conditions may correspond to conditions in which the continuous liquid phase is present in the reaction environment. Traditionally, the transalkylation process was carried out under gas phase transalkylation conditions. However, various advantages can be obtained by performing transalkylation under liquid phase conditions. For example, at least in part, the number of carbon desired in it a lower severity of the reaction conditions for performing the transalkylation on the liquid phase of the feed (e.g., C ₈ aromatic) Improved catalyst life and / or improved selectivity for the production of aromatic having . Other potential advantages of performing transalkylation under liquid phase conditions include lower reaction temperature, reduced or minimized energy consumption, reduced or minimized byproduct formation, and / or improved C ₈ aromatic yield.

The aromatization process often produces various single ring aromatics including C ₆ , C ₇ , C ₈ , C ₉ and C ₁₀ aromatics. If the desired product is, for example, a C ₈ aromatic, the methylation process can be used to convert C ₆ and / or C ₇ aromatics to C ₈ aromatics. It is also desirable to convert higher carbon content aromatics, such as C < ₉ > and / or C ₁₀ aromatics in this example to C ₈ aromatics. The transalkylation process may allow for this type of modification (removal, addition and / or substitution) of the alkyl side chain of the aromatic compound.

In some embodiments, suitable catalysts for conducting liquid phase transalkylation include molecular sieves having a three-dimensional, 12-membered ring (or more) pore network. While not wishing to be bound to any particular theory, molecular sieves having a three-dimensional 12-membered ring pore network can provide unexpected activity in transalkylation. Optionally, the Si / Al ₂ ratio of the molecular sieve can also be selected to promote an improved yield of C ₈ aromatics at a given temperature. Optionally, the catalyst comprising the 3-D 12-membered ring molecular sieve may further comprise a supported hydrogenation metal on the catalyst.

In another embodiment, suitable catalysts for conducting liquid phase transalkylation include molecular sieves having a one-dimensional, 12-membered ring (or more) pore network wherein the one-dimensional channel has a porosity of at least 6.0 angstroms, or at least 6.3 angstroms Channel size. Pore channels with larger pore channel sizes may also allow enhanced activity for transalkylation. For example, the MOR backbone structure has a pore 12-member pore channel size of about 6.45 angstroms, while the MEI backbone structure (ZSM-18) has a pore channel size of about 6.9 angstroms. In contrast, the MTW framework structure (ZSM-12) has a pore channel size of about 5.7 angstroms. Optionally, the Si / Al ₂ ratio of the molecular sieve may also be selected to promote an improved yield of C ₈ aromatics at a given temperature. Optionally, the catalyst comprising the 1-D 12-membered ring molecular sieve may further comprise a supported hydrogenation metal on the catalyst.

In other embodiments, suitable catalysts for carrying out liquid phase transalkylation have a pore channel size of at least 6.0 angstroms, or at least 6.3 angstroms / with the largest pore channel corresponding to a 12-membered ring or more, Or an acidic microporous material having another active surface having a size of at least 6.0 Angstroms. Optionally, the catalyst comprising the microporous material material may further comprise a supported hydrogenation metal on the catalyst. Optionally, the microporous material may be zeolite or another type of molecular sieve.

In another embodiment, suitable catalysts for conducting liquid phase transalkylation include molecular sieves having an MWW framework. Note that although the MWW framework has the 10-ring channel as the largest typical pore channel, the MWW framework crystal may also have a surface location that provides a structure similar to 12-member ring pores. While not wishing to be bound by any particular theory, it is believed that this surface location allows the MWW skeletal molecular sieve to act as a transalkylation catalyst. Optionally, the catalyst comprising the MWW skeletal molecular sieve may further comprise a supported hydrogenation metal on the catalyst.

In this discussion, performing a liquid phase transalkylation reaction may correspond to performing transalkylation under reaction conditions when at least a portion of the aromatic compound in the reaction environment is a liquid phase. The mole fraction of aromatic compounds in the liquid phase relative to the total aromatics, hereinafter referred to as the "liquid mole fraction," is at least 0.01, or at least 0.05, or at least 0.08, or at least 0.1, or at least 0.15, or at least 0.2, or at least 0.3, At least 0.4, or at least 0.5, and may have substantially all of the aromatic compounds in the liquid phase, as the case may be.

Due to the volume difference between the gas and the liquid, the volume fraction of the liquid phase in the reactor may be less than the mole fraction. As an approximation, the normal gas phase volume can be estimated using the ideal gas law. For transalkylation, the volume of a conventional aromatic liquid can be estimated by assuming an average molecular weight of about 100-120 g / mole and a liquid phase density of about 0.8 g / ml-0.9 g / ml. Under this assumption, having a liquid mole fraction of about 0.5 at a temperature of about 300 ° C and a partial pressure of an aromatic compound of about 300 psig corresponds to having a liquid volume fraction of about 5% -10% of the volume of the reaction environment It is expected. For a liquid mole fraction of about 0.1, the corresponding liquid volume is expected to correspond to 0.5% -1.0% of the reaction environment. While not wishing to be bound by any particular theory, it is believed that even small amounts of condensed (liquid) phase formation can substantially change the nature of the transalkylation reaction environment. Such a liquid phase may be preferentially formed at the surface in the reaction environment, for example, at the surface of the catalyst particles. Thus, small amounts of liquid formation may be potentially sufficient to effectively provide liquid phase reaction conditions.

In embodiments where the aromatic mole fraction of the liquid phase is at least 0.4, performing the liquid phase transalkylation corresponds to performing the transalkylation under conditions where the liquid phase corresponds to at least about 5% of the total volume of the reaction environment. In this embodiment, at least 30%, or at least 50%, or at least 70% by volume of the liquid in the reaction environment forms a single, continuous phase, as the continuous liquid phase may be formed in the reaction environment as the case may be. This, by contrast, may be accomplished, for example, by transalkylation under trickle-bed conditions, wherein a plurality of separate liquid phases may be formed in the fixed catalyst bed. In another embodiment, the transalkylation reaction can be carried out under sprinkling-layer conditions.

As used herein, the term "skeleton type" is used in the context of what is described in "Atlas of Zeolite Framework Types,"

The xylene yield used herein is calculated by dividing the total weight of the xylene isomers (para-, meta- and ortho-xylene) by the total weight of the product stream. The total weight of the xylene isomers can be calculated by multiplying the weight percent of xylene isomers measured by gas chromatography and the total weight of the product stream.

The weight ratio of the molecular sieve, the binder, the weight of the catalyst composition, the molecular weight of the molecular sieve to the catalyst composition, and the weight of the binder relative to the catalyst composition, based on the calcined weight (at 510 ° C in air for 24 hours) The weight of the molecular sieve, the binder and the catalyst composition is calculated based on the weight of the molecular sieve, the binder and the catalyst composition after calcination at 510 ° C in air for 24 hours.

As used herein, the term "aromatic" is to be understood as being within the purview of the art, including alkyl substituted and unsubstituted mononuclear and polynuclear compounds.

When n is a positive integer such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, the term "C _n " hydrocarbon, as used herein, ) ≪ / RTI > For example, the C _n aromatics refer to aromatic hydrocarbons having n number of carbon atom (s) per molecule. The term "C _{n +} " hydrocarbons, as used herein, wherein n is a positive integer such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ≪ / RTI > of at least " n " The term "C _n- " hydrocarbons, as used herein, wherein n is a positive integer such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ) ≪ / RTI >

n is a positive integer, for example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 of the term "C _n feedstocks" as used herein, C _n feedstock 50 Means a hydrocarbon having n number of carbon atom (s) per molecule in excess of (by weight or more than 75% by weight or more than 90% by weight) by weight. n is a positive integer, for example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 of the term "C _{n +} feedstock," as used herein, C _{n +} feedstock 50 Is meant to include hydrocarbons having at least n number of carbon atom (s) per molecule, greater than 75 wt% (or greater than 75 wt% or greater than 90 wt%). n is a positive integer, for example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 in the terms "C _n- feedstocks" as used herein, C _n- feedstock Means that the hydrocarbon comprises not more than 50% by weight (or more than 75% by weight or not more than 90% by weight) of hydrocarbons having not more than n number of carbon atom (s) per molecule. n is a positive integer, for example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 of the term "C _n aromatic feedstock," as used herein, C _n aromatic feedstock Means an aromatic hydrocarbon having greater than 50 wt% (or greater than 75 wt% or greater than 90 wt%) n number of carbon atom (s) per molecule. n is a positive integer, for example 1, 2, 3, 4, 5 and 6, the term "C _{n +} aromatic feedstock" used in the 7, 8, 9, 10, 11 and 12 herein, C _{n +} aromatic feedstock Means an aromatic hydrocarbon having greater than 50 weight percent (or greater than 75 weight percent or greater than 90 weight percent) of at least n carbon atom (s) per molecule. n is a positive integer, for example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 in the terms "C _n- aromatic feedstock," as used herein, aromatic C _n- Means that the feedstock comprises an aromatic hydrocarbon having greater than 50 weight percent (or greater than 75 weight percent or greater than 90 weight percent) of n or fewer carbon atom (s) per molecule.

Liquid phase transalkylation of aromatics

In the case of liquid phase alkylation, in some embodiments, suitable transalkylation catalysts include molecular sieves having a skeletal structure with a three-dimensional network of 12-membered ring pore channels. Examples of skeletons having a three-dimensional 12-membered ring include faujasite (including zeolite X or Y and USY), BEA (e.g. zeolite beta), BEC (polymorph C of beta), CIT- ITQ-24 (IWR), and ITQ-27 (IWV), preferably, for example, formazansite (CON), MCM-68 (MSE), hexagonal forzardite (EMT) Hexagonal paujasite, and beta (including all polymorphs of beta). It is noted that a material having a skeletal structure comprising a three-dimensional network of twelve circular pore channels may correspond to a combination of zeolites, silicoaluminophosphates, aluminophosphates, and / or any other convenience of skeletal atoms.

Additionally or alternatively, suitable transalkylation catalysts include molecular sieves with a framework having a one-dimensional network of 12-membered ring pore channels wherein the pore channels have a pore channel size of at least 6.0 angstroms, or at least 6.3 angstroms . The pore channel size of the pore channel is defined herein as the largest size sphere that can be dispersed along the channel. Examples of skeletons having one-dimensional 12-membered ring pore channels include, but are not limited to, mordenite (MOR), zeolite L (LTL), and ZSM-18 (MEI). It is noted that materials having a skeletal structure, including a one-dimensional network of twelve circular pore channels, may correspond to a combination of zeolites, silicoaluminophosphates, aluminophosphates, and / or any other convenience of skeletal atoms.

Additionally or alternatively, suitable transalkylation catalysts include molecular sieves having a MWW framework structure. Although the MWW framework structure does not have a 12-membered ring pore channel, the MWW framework structure includes surface locations with features similar to a 12-member ring opening. Examples of molecular sieves having a MWW skeleton structure include MCM-22, MCM-49, MCM-56, MCM-36, EMM-10, EMM-13, ITQ-1, ITQ-2, UZM- And interlayer extended zeolite. It is noted that a material having an MWW framework structure may correspond to a combination of zeolites, silicoaluminophosphates, aluminophosphates, and / or any other convenience of skeletal atoms.

Additionally or alternatively, suitable transalkylation catalysts may have a pore channel size of at least 6.0 angstroms, or at least 6.3 angstroms, or may have a pore channel size of at least 6.0 And an acidic microporous material having another active surface with a size of Angstroms. It is noted that these microporous materials may correspond to materials that are different from zeolites, silicoaluminophosphates, aluminophosphates, and / or molecular sieve type materials.

The molecular sieve may be characterized in that it is based on the case having a composition of molar ratio YO ₂ / X ₂ O ₃ = n, where X is a trivalent element such as aluminum, boron, iron, indium and / , Preferably aluminum and / or gallium, and Y is a tetravalent element such as silicon, tin and / or germanium, preferably silicon. For MWW skeletal molecular sieves, n can be less than about 50, such as from about 2 to less than about 50, usually from about 10 to less than about 50, more usually from about 15 to about 40. N is from about 10 to about 60, or from about 10 to about 50, or from about 10 to about 40, or from about 20 to about 60, or from about 20 to about 50, in the case of molecular sieves having a beta and / or polymorphic backbone structure Or from about 20 to about 40, or from about 60 to about 250, or from about 80 to about 250, or from about 80 to about 220, or from about 10 to about 400, or from about 10 to about 250, , Or from about 80 to about 400. In the case of molecular sieves with skeletal structures FAU, n ranges from about 2 to about 400, or from about 2 to about 100, or from about 2 to about 80, or from about 5 to about 400, or from about 5 to about 100, About 80, or about 10 to about 400, or about 10 to about 100, or about 10 to about 80. [ Optionally, said n value may correspond to an n value for the ratio of silica to alumina in the MWW, * BEA, and / or FAU backbone molecular sieve. In this optional embodiment, the molecular sieve may optionally correspond to an aluminosilicate and / or a zeolite.

Optionally, the catalyst may be present in an amount of 0.01 to 5.0%, or 0.01 to 2.0%, or 0.01 to 1.0%, or 0.05 to 5.0%, or 0.05 to 2.0% Or 0.05 to 1.0 wt%, or 0.1 wt% to 5.0 wt%, or 0.1 to 2.0 wt%, or 0.1 wt% to 1.0 wt% of a metal element of group 5-11 (according to the IUPAC periodic table) do. The metal element may be at least one hydrogenation component, for example, one or more metals selected from Groups 5-11 and 14 of the Periodic Table of the Elements, or a mixture of such metals, for example a hydride (or other multimetal) hydrogenation component. Optionally, the metal may be selected from Group 8-10, such as Group 8-10 precious metals. Specific examples of useful metals are iron, tungsten, vanadium, molybdenum, rhenium, chromium, manganese, ruthenium, osmium, nickel, cobalt, rhodium, iridium, copper, tin, noble metals such as platinum or palladium, Specific examples of useful deposit property combinations (or multimetal combinations) are that Pt is one of the metals, such as Pt / Sn, Pt / Pd, Pt / Cu, and Pt / Rh. In some embodiments, the hydrogenation component is palladium, platinum, rhodium, copper, tin, or a combination thereof. The amount of the hydrogenation component can be selected according to the hydrogenation activity and the catalytic activity balance. In the case of a hydrogenation component comprising two or more metals (e. G., A hydrate hydrogenation component), the ratio of the first metal to the second metal is from 1: 1 to about 1: 100, preferably from 1: 1 to 1:10 Lt; / RTI >

Optionally, suitable transalkylation catalysts may be molecular sieves having a constraint index of 1-12, and preferably less than 3, as the case may be. The constraint index can be measured by the method described in U.S. Pat. No. 4,016,218, which is incorporated herein by reference in its entirety for details of measuring the constraint index.

Additionally or alternatively, a transalkylation catalyst (e.g., a transalkylation catalyst system) may be used having reduced or minimized activity for dealkylation. The alpha value of the catalyst can provide an indication of the activity of the catalyst for dealkylation. In various embodiments, the transalkylation catalyst may have an alpha value of about 100 or less, or about 50 or less, or about 20 or less, or about 10 or less, or about 1 or less. The alpha value test is a measure of the decomposition activity of the catalyst, see U.S. Patent No. 3,354,078 and Journal of Catalysis, Vol. 4, p. 527 (1965); Vol. 6, p. 278 (1966); and Vol. 61, p. 395 (1980), each of which is incorporated herein by reference in its entirety. Experimental conditions of the test used herein were a constant temperature of 538 [deg.] C and a constant temperature of 538 [deg.] C [Journal of Catalysis, Vol. 61, p. 395, incorporated herein by reference.

It may be desirable to incorporate another material resistant to the temperature and other conditions used in the disclosure of the transalkylation process into the molecular sieve of the catalyst composition. Such materials include active and inactive materials and synthetic or naturally occurring zeolites and inorganic materials such as clay, silica, hydrotalcite, perovskite, spinel, inverse spinel, mixed metal oxides, and / or metal oxides such as Alumina, lanthanum oxide, cerium oxide, zirconium oxide, and titania. The inorganic material may be naturally occurring, or in the form of a bulk precipitate or gel comprising a mixture of silica and metal oxides.

The use of materials that are bonded or present together with each molecular sieve, which is itself catalytically active, i.e. during its synthesis, can change the conversion and / or selectivity of the catalyst composition. The inert material acts as a suitable diluent so that the transalkylated product can be obtained in an economical and orderly manner without controlling the rate of conversion and other means of controlling the rate of conversion. Such catalytically active or inactive materials may be incorporated into alumina or the like, for example, to improve the crushing strength of the catalyst composition under commercial operating conditions. In commercial applications, it is desirable to provide a catalyst composition having good crush strength because it is desirable to prevent the catalyst composition from being pulverized into a powdery material.

Naturally occurring clays that can be combined with each molecular sieve as a binder for the catalyst composition include montmorillonite and kaolin family, which include suet bentonite, and Dixie, McNamee, Georgia and Florida (Florida) clay, or kaolin commonly known as clay, or that the major mineral components are haloites, kaolinites, dickites, naclites or anauxites. These clays may be used in the originally mined raw material or in an initial calcined, acid treated or chemically modified state.

In addition to the above materials, each molecular sieve (and / or other microporous material) may comprise a binder or a matrix material such as silica, alumina, zirconia, titania, tori, beryllium, magnesia, lanthanum oxide, cerium oxide, Inorganic oxides selected from the group consisting of calcium oxide, hydrotalcite, perovskite, spinel, inverse spinel, and combinations thereof, such as silica-alumina, silica-magnesia, silica-zirconia, silica- Silica-alumina-zirconia, silica-alumina-magnesia, and silica-magnesia-zirconia, as well as silica-titania, and silica-alumina-zirconia. It may also be advantageous to provide at least a portion of the porous matrix binder material in colloidal form to facilitate extrusion of the catalyst composition.

In some embodiments, molecular sieves (and / or other microporous materials) can be used without additional matrices or binders. In another embodiment, the molecular sieve / microporous material can be mixed with the binder or matrix material such that the final catalyst composition contains the binder or matrix material in an amount ranging from 5 to 95 wt%, usually 10 to 60 wt%.

Prior to use, the vapor treatment of the catalyst composition may be used to minimize the aromatic hydrogenation activity of the catalyst composition. In the vaporization process, the catalyst composition is contacted with 5 to 100% of the steam at a temperature of at least 260 DEG C to 650 DEG C for at least one hour, typically 1 to 20 hours, at a pressure of typically 100 to 2590 kPa-a.

The hydrogenation component can be incorporated into the catalyst composition by any convenient method. This incorporation method can include co-crystallization, exchange with a catalyst composition, liquid phase and / or gas phase impregnation, or mixing of molecular sieve and binder, and combinations thereof. For example, in the case of platinum, the platinum hydrogenation component may be incorporated into the catalyst by treating the molecular sieve with a solution containing platinum metal containing ions. Suitable platinum compounds for impregnating the catalyst is platinum on various types of containing chloroplatinic acid, platinum chloride and platinum first ammin complex compounds, such as _{Pt (NH 3) 4 Cl 2} .H 2 O or (NH _{3) 4} Pt (NO ₃ ) _2. H ₂ O is included. Palladium can be impregnated on the catalyst in a similar manner.

Alternatively, the compound of the hydrogenation component can be added to the molecular sieve, when it is combined with the binder, or after the molecular sieve and binder are formed into particles by extrusion or pelleting. Another option may be to use a coupling agent comprising a hydrogenation component and / or a hydrogenation component.

After treatment with the hydrogenating component, the catalyst is dried by heating at a temperature of 65 [deg.] C to 160 [deg.] C, typically 110 [deg.] C to 143 [deg.] C for at least 1 minute, typically for up to 24 hours at a pressure in the range of 100 to 200 kPa-a . The molecular sieve can then be calcined in a dry gas stream, such as air or nitrogen, at a temperature of 260 ° C to 650 ° C for 1-20 hours. Calcination is usually carried out at pressures in the range of 100 to 300 kPa-a.

Also, prior to contacting the catalyst composition with the hydrocarbon feed, the hydrogenation component may optionally be sulfated. This is conveniently accomplished by contacting the catalyst with a sulfur source, such as hydrogen sulphide, at a temperature in the range of about 320 to 480 [deg.] C. The sulfur source can be contacted with the catalyst through a carrier gas, such as hydrogen or nitrogen. Sulphiding itself is known, and the sulphation of the hydrogenated components can be achieved without routine experimentation by those skilled in the art having the present disclosure.

In various embodiments, the feedstock for transalkylation may comprise at least one aromatic compound containing at least 9 carbon atoms. Specific C ₉₊ aromatics found in conventional feeds include mesitylene (1,3,5-trimethylbenzene), duren (1,2,4,5-tetramethylbenzene), hemimellitene (1,2, Trimethylbenzene), 1, 2-methylethylbenzene, 1, 3-methylethylbenzene, 1, 4-methylethylbenzene, propyl-substituted benzene, butyl Substituted benzene, and dimethylethylbenzene. A suitable source of C ₉₊ aromatics is any C ₉₊ fraction from any refinery process that is aromatic-rich. The aromatic fraction is significant percentage of C ₉₊ aromatic, for example, and contains a C ₉₊ aromatic, at least 80% by weight, preferably a hydrocarbon group of at least 80% by weight, more preferably more than 90% by weight of C ₉ to C ₁₂ . Typical refinery fractions that may be useful include catalyst modifications, fluid catalysed cracked (FCC) naphtha or thermocatalytic cracked (TCC) naphtha.

The feedstock may also comprise benzene or toluene. In a practical embodiment, the feed to the transalkylation reactor comprises _{C9 +} aromatic hydrocarbons and toluene. The feed may also comprise recycled / unreacted toluene and a C ₉₊ aromatic feedstock obtained by distillation of the effluent product of the transalkylation reaction itself. Typically, the toluene is comprised of 0-90 wt%, e.g., 10-70 wt% of the total feed, whereas the C ₉₊ aromatics constitutes 10-100 wt%, e.g., 30-85 wt% of the total feed for the transalkylation reaction, . Additionally or alternatively, the feed may comprise benzene. Hydrogen may also be introduced into the transalkylation process.

The feedstock may be characterized by methyl to a single aromatic ring molar ratio. In some embodiments, the combined feedstock (combination of C ₉₊ and C ₆ -C ₇ aromatic feedstock) has a single aromatic ring mole ratio in the range of from 0.5 to 4, preferably from 1 to 2.5, more preferably from 1.5 to 2.25 ≪ / RTI > Methyl for a single aromatic ring molar ratio can be adjusted by adjusting the relative flow rates of the C ₉₊ and C ₆ -C ₇ aromatic feedstocks and / or the relative C ₆ / C ₇ ratio of the C ₆ -C ₇ aromatic feedstocks.

The transalkylation process may be used to convert a portion of the C ₉ aromatic and / or C ₁₀ aromatics to xylene. If desired, the feed can comprise a C ₉ or C ₉₊ aromatic having a reduced or a minimal amount, ethyl or propyl side chains. In some optional embodiments, the feedstock may also comprise at least about 1%, or at least about 2%, or at least about 5%, or at least about 10% by weight polynuclear aromatics.

In some optional embodiments, the feedstock may have a reduced or minimized content of aromatics substituted with C _{2 +} alkyl side chains. Because the xylene contains only the methyl (C ₁ ) side chain, any C ₂₊ alkyl side chain in the reaction environment may tend to reduce the amount of xylene formation. In the case of liquid phase transalkylation, it may be desirable to use a feedstock having less than about 5%, less than about 2%, or less than about 1% by weight aromatics containing C ₂₊ side chains in the feedstock.

Generally, the conditions used in the liquid phase transalkylation process are about 400 ° C or lower, or about 360 ° C or lower, or about 320 ° C or lower, and / or at least about 100 ° C, or at least about 200 ° C, Or from 100 캜 to 340 캜, or from 230 캜 to 300 캜; From 2.0 MPa-g to 10.0 MPa-g, or from 3.0 MPa-g to 8.0 MPa-g, or from 3.5 MPa-g to 6.0 MPa-g; The molar ratio of H _{2 to} hydrocarbons from 0 to 20, or from 0.01 to 20, or from 0.1 to 10; And the weight hourly space velocity ("WHSV") of the total hydrocarbon feed to the reactor (s) of from 0.1 to 100 hr ^-1 , or from 1 to 20 hr ^-1 . Optionally, the pressure during transalkylation may be at least 4.0 MPa-g. Note that H ₂ is not absolutely necessary during the reaction and, in some cases, transalkylation can be carried out without the introduction of H ₂ . The feed may be exposed to the transalkylation catalyst under fixed bed conditions, fluid bed conditions, or other suitable conditions where a substantial liquid phase is present in the reaction environment.

In addition to conforming to the general conditions above, the transalkylation conditions can be selected such that the desired amount of hydrocarbons (reactants and products) in the reactor is in the liquid phase. Figure 1 shows a calculation for the amount of liquid that should be present as a feed corresponding to a 1: 1 mixture of toluene and mesitylene under various conditions considered to be representative conditions of potential transalkylation conditions. The calculation of Figure 1 shows the molar fraction in liquid phase as a function of temperature. Separate three groups of calculations shown in Figure 1 correspond to a vessel containing a specific pressure based on the introduction of a toluene / mesitylene feed into the reactor and a specific relative molar volume of H ₂ . The first data set corresponds to a 1: 1 molar ratio of toluene / mesitylene feed and H ₂ at 600 psig (about 4 MPa-g). The first data set corresponds to a 2: 1 molar ratio of toluene / mesitylene feed and H ₂ at 600 psig (about 4 MPa-g). The third data set corresponds to a 2: 1 molar ratio of toluene / mesitylene feed and H ₂ at 1200 psig (about 8 MPa-g).

As shown in FIG. 1, temperatures below about 260 占 폚 are all calculated conditions including a combination of the lower pressure (600 psig) shown in FIG. 1 and the lower ratio of feed to hydrogen (1: 1) It is possible to induce the formation of a considerable liquid phase (liquid mole fraction of at least 0.1). It is noted that based on a ratio of feed to hydrogen of 1: 1, the total pressure of 600 psig corresponds to a partial pressure of the aromatic feed of about 300 psig. Higher temperatures up to about 320 DEG C may also have a liquid phase (at least 0.01 mole fraction) depending on the pressure and the relative amount of reactants in the environment. More generally, temperatures such as at most 360 ° C or at most 400 ° C or more can also be used for liquid phase transalkylation if the combination of temperature and pressure in the reaction environment can lead to a liquid mole fraction of at least 0.01. Conventional transalkylation conditions usually involve temperatures above 350 DEG C and / or pressures below 4 MPag, but these conventional transalkylation conditions do not include a combination of pressure and temperature that leads to a liquid mole fraction of at least 0.01 Keep in mind.

The effluent produced from the (liquid) transalkylation process to the total weight of hydrocarbons in the effluent may comprise at least about 4%, or at least about 6%, or at least about 8%, or at least about 10% Yield.

The transalkylation process produces an effluent that can be separated based on boiling or distillation to form one or more effluent streams. The first effluent stream separated from the transalkylation effluent may be a C ₆ -C ₇ stream (possibly including unreacted C ₆ -C ₇ compound) which may be at least partially recycled to the transalkylation. The second effluent stream separated from the transalkylation effluent may correspond to a C ₉₊ compound, possibly including unreacted C ₉₊ compounds. The third effluent stream separated from the transalkylation effluent may correspond to a C ₈ aromatic stream. Optionally, one of the first effluent stream, the second effluent stream or the third effluent stream may correspond to the remainder of the methylated effluent after separation of the other effluent stream.

In some embodiments, the naphthalene containing streams, such as those found in various refineries and / or chemical plant streams, may be treated through a liquid phase transalkylation process to form useful products and / or streams. For example, in some embodiments, the feedstock for the liquid phase transalkylation process may comprise 8-24 wt% naphthalene and 60-90 wt% C ₉ alkylbenzene. In one particular embodiment, the feedstock comprises a combination of a first feedstock stream and a second feedstock stream. The first feed stream comprises about 2.6 weight percent trimethylbenzene, about 1.3 weight percent indane, about 1.9 weight percent diethylbenzene, 7.8 weight percent methylpropylbenzene, about 34.1 weight percent dimethylethylbenzene, about 13.8 weight percent % Tetramethylbenzene, about 9.6 wt% methylindane, about 8.3 wt% naphthalene, and about 20 wt% other components (e.g., heavy compounds). The second feedstock stream comprises about 59.1 wt% methylethylbenzene, about 24.0 wt% naphthalene, about 6.2 wt% methylnaphthalene, and about 10.7 wt% other components (e.g., heavy compounds). The first feedstock stream and the second feedstock stream may be taken from any suitable feed such as a product, effluent, or refinery and / or other stream found in a chemical plant. Further, in another embodiment, the feed may be derived from coal, fluid catalytic cracking (FCC), circulating diesel (LCO), C1R, methane reforming, C2A, ethane reforming, or a combination thereof.

The first and second feedstock streams described above are fed through feedstock formulated into a liquid phase transalkylation catalyst (i.e., a blended feedstock comprising a percentage of the first feedstock stream and the second feedstock stream) May be blended in any suitable ratio beforehand. In some embodiments, the molar ratio of the first feedstock stream to the second feedstock stream may be approximately 1: 1. In at least some embodiments, the transalkylation feedstock (e.g., the first feedstock stream, the second feedstock stream, some combinations of the first feedstock stream and the second feedstock stream, or some other feedstock) relative to the total amount of feedstock Raw material stream) has a naphthalene concentration of 5 to 50% by weight.

In at least some embodiments, the molar fraction of the liquid feedstock (i. E., The first feedstock stream and / or the second feedstock stream) relative to the total amount of feedstock is at least 0.01, or at least 0.05, or at least 0.08, or At least 0.1, or at least 0.15, or at least 0.2, or at least 0.3, or at least 0.4, or at least 0.5, and optionally up to substantially all of the feedstock in the liquid phase.

In some embodiments, the transalkylation catalyst may comprise MCM-49, USY, beta, or some combination thereof. In addition, the reaction conditions for the liquid phase transalkylation are carried out at a temperature of 200 ° C to 600 ° C, a pressure of 100 to 800 psig, and a space velocity per weight hour for the total hydrocarbon feed to the reactor (s) of 0.5 to 5.0 hr ^-1 "WHSV").

The transalkylated product resulting from the liquid phase transalkylation process described above may contain at least 99.0% aromatic compounds and may have a mixed aniline point (solubility measure) of less than 15 ° C. In some embodiments, the transalkylated product resulting from the liquid phase transalkylation process described above is suitable for use in, or for use in, compressor oil, among other things, heavy aromatic solvents (e.g., those used in agricultural applications) can do.

Example 1-6: Liquid phase transalkylation with various catalysts

In Examples 1-6, various types of catalysts with 12-membered ring channels and / or active sites were used in the transalkylation reaction. (57:43 weight ratio) consisting of chemical grade toluene and mesitylene in a 1: 1 molar ratio at an initial temperature of 220 DEG C, feed 1 to 1 molar ratio H ₂ , and space velocity per weight hour of about 6 hr ^-1 , Lt; / RTI > The reaction was carried out in an upflow fixed bed unit equipped with a 5-mm (inner diameter) stainless steel reactor. Once the reaction reached a steady state, the product stream was analyzed by on-line GC. The product analysis was repeated while increasing the reactor temperature from 220 to 400 ° C at intervals of 10 ° C. The results obtained at 260 占 폚 are shown in Table 1 below.

In the case of Example 1, a ZSM-12 catalyst was used. The catalyst was combined with 35% alumina in 1/16 "cylindrical extrudate, vaporized at 900 ° F. for 5.25 hours, and cut to 1/16" length. The catalyst was then dried by flowing N ₂ at 250 ° C and 300 psig (2.1 MPa) for 3 hours before exposure to the feed. It is noted that the catalyst does not comprise a separate hydrogenation metal. Catalysts for Examples 2-6 were prepared in a similar manner with respect to catalyst weight, amount of binder, catalyst size, and other vaporization / drying conditions. The catalyst for Example 2 contained zeolite beta instead of ZSM-12. Example 3 included a superstable Y. [ Example 4 contained mordenite. Example 5 included MCM-49. Example 6 included MCM-56. For each catalyst, the ratio of Si / Al _{2 in} the catalyst is also given in Table 1 below.

The transalkylation conditions presented in Table 1 below correspond to about 300 psig (about 2.1 MPa-g) and about 260 < 0 > C. Under this condition, the mole fraction of the hydrocarbon feed corresponding to the liquid is considered to be 0.01 to 0.1. Thus, the conditions in Table 1 below are believed to correspond to having a small but significant amount of the liquid feed (and product, if any) in the reaction environment.

The ZSM-12 catalyst of Example 1 corresponds to the one-dimensional 12-membered ring molecular sieve previously used for gas phase transalkylation. This is described, for example, in the examples provided in U.S. Patent No. 8,163,966.

As shown in Table 1 above, ZSM-12 provides only a minimum xylene yield when transalkylation is performed at a temperature low enough to allow a substantial liquid phase to be present. Additionally, this low or minimum xylene yield is generated after about 75% of the way to equilibrium in terms of mesitylene conversion is reached. This indicates that attempting to perform liquid phase transalkylation with ZSM-12 has a low selectivity for xylene formation. This is in contrast to the xylene yields for molecular sieves in Examples 2 and 3 (beta and USY) containing a three-dimensional 12-membered ring pore network. While not wishing to be bound to any particular theory, it is believed that a three-dimensional 12-membered ring pore network can provide additional activity advantages under liquid phase transalkylation conditions. The three-dimensional 12-membered ring molecular sieve of Examples 2 and 3 provided significant selectivity for xylene formation compared to ZSM-12, although only a modest amount of the liquid feed was present at 260 [deg.] C and 300 psig.

With respect to Example 4, mordenite corresponds to a one-dimensional, 12-membered ring molecular sieve having a pore channel size larger than ZSM-12. It appears that mordenite provides enhanced selectivity to xylene formation compared to ZSM-12. This suggests that one-dimensional 12-membered ring zeolite of other large pore diameters can also provide enhanced selectivity. ZSM-18 is another example of one-dimensional 12-membered ring zeolite with pore channel size greater than ZSM-12.

Examples 5 and 6 show the results from exposing the toluene / mesitylene feed to the MWW skeletal catalyst. Both MCM-49 (Example 5) and MCM-56 (Example 6) appear to present minimal selectivity for xylene formation under transalkylation conditions when used without further hydrogenation metal.

The amount of mesitylene conversion is also an indicator of transalkylation activity. It is shown in Table 1 that the zeolite beta catalyst (Example 2) has the highest conversion (about 70%) of mesitylene. While most of the mesitylene is converted to other trimethylbenzenes, it still demonstrates the generally high activity for transalkylation. It is noted that mordenite (Example 4) has a similar mesitylene conversion with lower xylene yield.

The USY catalyst (Example 3) appears to have a low mesitylene conversion of about 23%, but the USY catalyst also provides the second highest xylene yield. This suggests the possibility of increased xylene yield using USY (or other FAU backbone molecular sieve) under customized conditions for use with the catalyst.

Examples 7-10: Batch transalkylation

In a separate batch experiment using the same 1: 1 mesitylene / toluene feed (mol / mol) of the liquid phase at about 260 ° C and about 400 psig (about 2.8 MPa-g), various catalysts were evaluated for xylene production . For the batch operation in Examples 7-10, 15 g of catalyst was dried at 260 占 폚 for one hour and then loaded into the catalyst basket. For the MCM-22 catalyst of Example 8, the catalyst was unbound and only 13.5 g of MCM-22 catalyst was loaded into the catalyst basket. For each of Examples 7-10, a catalyst basket and a 150 g feed were placed inside a 600-mL autoclave reactor. The reactor temperature was raised to 260 ° C and then pressurized with H ₂ while maintaining a stirring speed of 500 rpm until a pressure of 400 psig was realized. Once the temperature reached 260 ° C, 2-cc samples were collected for GC analysis. Sample collection was continued at 1 hour intervals for 5 hours. Later, the reactor was cooled. The catalyst for Example 7 is mordenite (65 wt% binder / 35 wt% alumina binder); The catalyst of Example 8 is MCM-22 (80/20 alumina bonded); The catalyst of Example 9 is 0.15 wt% FAU (80/20 alumina combined) also containing Pd supported on the catalyst; The catalyst of Example 10 was MCM-49 (80/20 alumina bonded). The results from Examples 7-10 are shown in Figures 2-5.

Figure 2 (Example 7) shows that mordenite has a liquid phase, but has activity for mesitylene conversion under batch conditions with low or reduced amounts of toluene conversion and xylene formation. MCM-22 (Figure 3, Example 8) and MCM-49 (Figure 5, Example 10) both demonstrate somewhat higher amounts of toluene conversion and xylene production. The addition of 0.15 wt.% Pd to the FAU (Fig. 4, Example 9) also provided a catalyst that appeared to provide high activity in the formation of xylenes. The amount of mesitylene and toluene converted in Figure 4 is believed to correspond to the amount of equilibrium of conversion.

Examples 11-16: Additional features of the transalkylation product

In Examples 11-16, a 1: 1 molar toluene / mesitylene feed was exposed to various catalysts at a total pressure of about 600 psig (about 4.1 MPa-g) and at a temperature in the range of 240 ° C to 380 ° C. After the treatment was started at 240 캜, it was increased to 300 캜 at intervals of 15 캜 in order to investigate various treatment conditions. In addition, work was performed on some catalysts at 325 ° C and 380 ° C. The feed was introduced into the reactor at a space velocity per weight hour of about 2 hr < ^-1 >. The molar ratio of hydrogen to feed was about 1: 1. The catalyst used for transalkylation was MCM-49 (Example 11); MCM-49 (Example 12) with 0.15 wt% Pd; Zeolite beta (Example 13) having a Si / Al ₂ ratio of about 40; Zeolite beta (Si / Al ₂ ) (ratio about 40) with 0.15 wt% Pd (Example 14); A zeolite beta second version with a ratio of Si to Al ₂ of about 200 (Example 15); And FAU (Example 16). All catalysts were combined with alumina at a weight ratio of 80:20.

Figure 6 shows the xylene yield for Example 11 corresponding to being treated in the presence of MCM-49. Catalysts have low activity at the temperatures suggested, leading to limited production of xylene.

Figure 7 shows the xylene yield for Example 12 corresponding to being treated in the presence of MCM-49 with 0.15 wt% of Pd supported on the catalyst. The addition of 0.15 wt% Pd appears to increase the activity of MCM-49 to convert the feed to xylene. Note that the 20+ wt% xylene yield on the feed, which occurs at temperatures above 285 ° C, is a yield that can be found in commercial gas phase processes. However, such yields in gas phase processes may require transalkylation temperatures of typically above 380 < 0 > C. Note that the final data point corresponding to 285 DEG C indicates that the same catalyst is used for the final treatment operation. Lower activity at final operation at 285 DEG C indicates that deactivation of some catalysts can occur over time. However, reference is made to Example 17 below for evidence that treatment at approximately constant temperature can not induce significant catalytic deactivation over an extended period of time.

Figure 16 shows a further comparison of the activity of MCM-49 with and without the use of supported hydrogenation metals under another set of transalkylation conditions. In the case of the process of FIG. 16, a feed with a 1: 1 ratio of mesitylene to toluene at a total pressure of about 300 psig (about 2.1 MPa-g) and a temperature range starting from about 280 & The wt% Pd / MCM-49 catalyst was exposed.

Figure 8 shows the xylene yield for Example 13, corresponding to being treated in the presence of zeolite beta with a Si / Al ₂ ratio of about 38. Although all of the reaction temperatures presented are below 300 ° C, the zeolite beta induces a significant production of xylene. Likewise, the final portion of the work at lower temperatures may exhibit some catalyst deactivation over time after performing transalkylation at higher temperatures.

Figure 9 shows the xylene yield for Example 14 corresponding to being treated in the presence of zeolite beta (Si / Al ₂ ratio of about 38) with 0.15 wt% catalyst phase Pd. Addition of hydrogenated metal to zeolite beta appears to significantly reduce xylene production. This is in contrast to the results presented in Example 12 / Figure 7, where addition of the hydrogenated metal to the MWW skeletal catalyst leads to an improvement in activity for xylene production.

Figure 10 shows the xylene yield for Example 15 corresponding to being treated in the presence of zeolite beta with a higher Si / Al ₂ ratio of about 200. The activity of xylene production of beta at higher Si / Al ₂ ratios is lower than that from Example 13.

Figure 11 shows the xylene yield for Example 16 corresponding to being treated in the presence of an FAU catalyst. Figure 11 appears to suggest that FAU has some activity in xylene production. Additionally, when H ₂ is removed from the reaction environment at a temperature of about 330 ° C., an increase in activity of about 50% compared to transalkylation in the presence of hydrogen at 330 ° C. was observed.

12 combines the xylene yield results from Examples 11-16 into a single plot. Figure 12 also illustrates xylene production under gas phase conditions using a catalyst system corresponding to a mix of ZSM-5 and ZSM-12. The feed to the gaseous ZSM-5 / ZSM-12 system was an aromatic mixture. The aromatic mixture was treated at a space velocity of 350 psig, 6 hr < ^-1 > weight hour and 380 < 0 > C to 440 < 0 > C. Figure 12 shows that MCM-49 with zeolite beta (positive proportions) and 0.15 wt% Pd has significant active advantages in terms of temperature to achieve a specific yield compared to treating with ZSM-5 / ZSM-12 catalyst system under gas phase conditions Lt; / RTI > For example, zeolite beta (Si / Al ₂ ratio of 38) has an active advantage of about 140 ° C, while a beta of higher Si / Al ₂ ratio has an active advantage of about 60 ° C.

13 shows the relative amounts of xylene yield and benzene yield during the treatment operations of Examples 11-16. Generally, the yield of benzene from all the processing operations of Examples 11-16 was less than 1% by weight. As a result, most of the variables in the xylene to benzene yield ratio are due to differences in xylene xylene yields.

Figure 14 shows the yield of heavy aromatics (C ₁₀₊ ) during the treatment operations of Examples 11-16. 14 shows a catalyst comprising Pd as a supported hydrogenation metal derived from the increased formation of a heavy aromatic compound.

Example 17 - Catalyst stability

As a test of catalyst stability, naphthalene conversion was carried out under transalkylation conditions on a feed containing a mixture of aromatics. While naphthalene is a 2-ring aromatic, it is believed that the stability during naphthalene conversion can be similar to the stability during transalkylation of a 1-ring aromatic. It is also believed that during gas phase transalkylation, the presence of C ₁₀₊ aromatics induces catalyst deactivation. Thus, stability in the presence of a C ₁₀₊ compound can be useful for a transalkylation catalyst.

The transalkylation of naphthalene was carried out using two types of feedstocks. The first feedstock corresponds to feedstock A in Table 2 below. The second feedstock corresponds to a 2: 1 (by weight) blend of feed B and feed A.

As can be seen from Table 2 above, feed A is a complex mixture of C ₉ -C ₁₀ , which is predominantly a C ₁₀ aromatic. Dimethylethylbenzene is one of the major components in feed A. Feed A also contains about 8% naphthalene. Feed B is composed of 59% methyl ethylbenzene, 24% naphthalene and 6% methyl naphthalene. This may be a representative example of a fraction type that can be produced as a residual or bottom fraction from the process of methylating toluene to form xylene, for example. In the second feedstock, feed B was tested with a 2/1 mixture with feed A. The "bottom" portion of feed A and feed B represents a heavy component and / or a component having more than two aromatic rings.

The feedstock was exposed to the MCM-49 catalyst over a period of one day at 275 DEG C, a space velocity per weight hour of 1.5 hr < ^-1 > and a pressure of about 500 psig. Figure 15 shows the amount of naphthalene conversion measured over time during the transalkylation operation. As shown in Figure 15, the naphthalene conversion was stable during the exposure of both types of feedstock to the catalyst. For the second feedstock, the transalkylation activity was stable over the course of 24 days.

Example 18 - Liquid phase transalkylation of a naphthalene containing stream

In Example 18, a 1: 1 weight ratio blend of feeds A and B from Table 2 above was blended at a temperature of 280 DEG C over one day, a space velocity per weight hour of 1.5 hr <" ¹ & -49 catalyst. Figure 17 shows the amount of naphthalene conversion measured over time during the transalkylation operation. As shown in Figure 17, the naphthalene conversion was substantially stable during the 25 day exposure with an average conversion of about 54%. The resulting transalkylation product was distilled and a fraction 235-305 ° C was found to have 99% + aromatics and a mixed aniline point of about 13 ° C.

While the disclosed embodiments have been described and illustrated with respect to particular embodiments, it is to be understood that the invention is not to be limited to the specific details disclosed, but extends to all equivalents within the scope of the claims. Unless otherwise stated, all percentages, parts, ratios, etc. are by weight. Unless otherwise indicated, references to a compound or ingredient itself include a compound or component, such as a mixture of compounds, in combination with other elements, compounds, or components. In addition, when an amount, concentration or other value or parameter is presented as a list of upper and lower limits, it is intended to specifically disclose all ranges formed from any pair of upper and lower limits, irrespective of whether the ranges are individually disclosed Should be understood. All patents, test procedures and other references cited herein, including priority, are fully incorporated by reference for all jurisdictions in which such incorporation is permitted to the extent that the disclosure is consistent.

Claims (23)

As a liquid phase transalkylation method of an aromatic compound,
Exposing an aromatic feedstock comprising at least one of benzene and toluene and a C ₉₊ aromatic to a transalkylation catalyst under transalkylation conditions effective to produce a transalkylation effluent
Lt; / RTI >
The mole fraction of the aromatic compound in the liquid phase in the feedstock relative to the total amount of aromatic compounds in the feedstock is at least about 0.01 under effective transalkylation conditions,
The transalkylation effluent has a higher weight percentage of C ₈ aromatics than the feedstock,
The catalyst
Molecular sieves having a three-dimensional 12-membered ring or more pore-
A molecular sieve having a one-dimensional, 12-membered ring or more pore network, wherein the one-dimensional channel has a pore channel size of at least 6.0 angstroms,
An acidic microporous material having a pore channel size of at least 6.0 angstroms, and
Molecular sieve with MWW framework
≪ / RTI > The method of claim 1, wherein the molecular sieve comprises a three-dimensional 12-membered ring or more pore network. 3. The method of claim 2, wherein the molecular sieve comprises a skeletal structure selected from the group consisting of FAU, CON, EMT, MSE, ISV, IWR, IWV, 4. The method of any one of claims 1 to 3, wherein the molecular sieve has a skeletal structure selected from the group consisting of FAU, EMT, beta polymorph, or a combination thereof. The method of claim 4, wherein the molecular sieve has a beta polymorphic framework structure and a Si / Al ₂ ratio of from about 10 to about 400. 5. The method of claim 4, wherein the molecular sieve has an FAU framework structure and a Si / Al ₂ ratio of from about 2 to about 400. The method of claim 1 wherein the molecular sieve has a one-dimensional, 12-membered ring or more pore network. 8. The method of claim 7, wherein the molecular sieve has a backbone structure of MOR, MEI, or a combination thereof. The method of claim 1, wherein the acidic microporous material or molecular sieve has a pore channel size of at least 6.3 angstroms. The method of claim 1, wherein the molecular sieve comprises MCM-22, MCM-49, MCM-56, or a combination thereof. 11. The process according to any one of claims 1 to 10, wherein the molar fraction of aromatic compounds in the liquid phase in the feedstock relative to the total amount of aromatic compounds in the feedstock is at least about 0.1 under effective transalkylation conditions. The process according to any one of claims 1 to 11, wherein the effective transalkylation conditions comprise a temperature of less than 280 ° C, a total pressure of at least 4.0 MPa g, a molar ratio of H _{2 to} hydrocarbon in the feedstock of from about 0.01 to 20, / RTI > 13. The process of any one of claims 1 to 12, wherein the catalyst further comprises from 0.01% to 5% by weight of at least one metal from Groups 5-11 and Group 14. 14. The method of claim 13, wherein at least one metal from Groups 5-11 and 14 is selected from the group consisting of Pd, Pt, Ni, Rh, Cu, Sn, Fe, W, V, Mo, Re, Cr, Mn, , Ir, or a combination thereof. 15. The method of claim 14, wherein the at least one metal from Groups 5-11 and 14 is Pd, Pt, Ni, or combinations thereof. 16. The process according to any one of claims 13 to 15, wherein the catalyst comprises a bimetallic metal. 17. The method of claim 16, wherein the deposit-resistant metal is Pt / Sn, Pt / Cu, Pt / Pd, Pt / Rh or combinations thereof. Claim 1 to claim 17, wherein according to any one of, wherein the feedstock is a feedstock in the naphthalene 2% by weight or more, polynuclear aromatic 1 less than 5% by weight aromatic containing% by weight or more, the side chain C ₂₊ or a combination thereof ≪ / RTI > As a liquid phase transalkylation method of an aromatic compound,
Exposing an aromatic feedstock comprising at least one of benzene and toluene and a C ₉₊ aromatic to a transalkylation catalyst under transalkylation conditions effective to produce a transalkylation effluent
Lt; / RTI >
Wherein the effective transalkylation conditions comprise a temperature of less than 280 占 폚, a total pressure of at least 4.0 MPa g, a molar ratio of H _{2 to} hydrocarbon in the feedstock of from about 0.01 to 20,
The molar fraction of aromatic compounds in the liquid phase in the feedstock relative to the total amount of aromatic compounds in the feedstock is at least about 0.1 under effective transalkylation conditions,
The transalkylation effluent has a higher weight percentage of C ₈ aromatics than the feedstock,
Wherein the catalyst comprises a molecular sieve having an MWW framework and 0.01% to 5.0% Pd by weight,
Wherein the molecular sieve comprises MCM-22, MCM-49, MCM-56 or a combination thereof. 20. The process of claim 19, wherein the feedstock further comprises in the feedstock at least 2% by weight of naphthalene, at least 1% by weight of polynuclear aromatic, less than 5% by weight of aromatic containing C ₂₊ side chains, or combinations thereof. As a liquid phase transalkylation process,
Exposing the feedstock comprising 5 to 50% by weight of naphthalene and at least one alkylbenzene to the transalkylation catalyst to produce a transalkylation effluent
Lt; / RTI >
Wherein the molar fraction of feedstock in the liquid phase, relative to the total amount of feedstock, is at least about 0.1 under effective transalkylation conditions,
Wherein the transalkylation effluent comprises an aromatic compound of greater than 99.0% and an aniline point of less than or equal to 15 < 0 > C. 22. The method of claim 21, wherein the transalkylation catalyst comprises MCM-49. 23. The method of claim 21 or 22 wherein the step of exposing the feedstock to transalkylation at a temperature of about 200 DEG C to 600 DEG C, a space velocity per weight hour of about 0.5 to 5.0 hr <" ¹ & And exposing the catalyst to a catalyst.

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