WO2019008490A1

WO2019008490A1 - Process for producing aromatization catalyst and process for aromatizaton

Info

Publication number: WO2019008490A1
Application number: PCT/IB2018/054871
Authority: WO
Inventors: Sreenivasarao GAJULA; Amit Kumar; Ziyad KOTTAVARITHOTTIL; Sivakumar SREERAMAGIRI; Eswara Rao MUPPARAJU; Suman Kumar Jana; Anthonisamy SELVANATHAN
Original assignee: Sabic Global Technologies B.V.
Priority date: 2017-07-05
Filing date: 2018-06-29
Publication date: 2019-01-10

Abstract

A process for producing an aromatization catalyst is provided. The process comprises contacting an inorganic support with a catalytic metal solution to deposit a catalytic metal onto the inorganic support to obtain the aromatization catalyst and carburizing the aromatization catalyst. The catalytic metal comprises chromium, cobalt, gallium, iron, magnesium, molybdenum, vanadium, zinc, or a combination comprising at least one of the foregoing, preferably molybdenum. The inorganic support comprises a zeolite and a silica to alumina molar ratio of the zeolite is 10 to 50, preferably 13 to 30. The pH of the catalytic metal solution is greater than or equal to 9, or greater than or equal to 10.

Description

PROCESS FOR PRODUCING AROMATIZATION CATALYST AND PROCESS FOR

AROMATIZATON

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of US Patent Application Serial No.

62/528,621 filed July 5, 2017, which is incorporated herein in its entirety by reference.

BACKGROUND

[0002] Methane aromatization is a promising route for production of benzene. In the aromatization reaction, aromatization catalysts can be used to convert the methane to benzene. As the aromatization reaction progresses, the benzene productivity (i.e., grams of benzene produced per kilogram of catalyst per hour) can decrease due to formation of coke on the aromatization catalyst (i.e., coking). This coking can decrease the life of the aromatization catalyst. Such a decrease in the benzene productivity and life of the aromatization catalyst can affect the technological and economic viability of methane aromatization as a route for production of benzene.

[0003] Therefore, it would be desirable to provide improved aromatization catalysts and processes for aromatization of methane to produce benzene.

SUMMARY

[0004] A process for producing an aromatization catalyst includes contacting an inorganic support with a catalytic metal solution to deposit a catalytic metal onto the inorganic support to obtain the aromatization catalyst and carburizing the aromatization catalyst. The catalytic metal includes chromium, cobalt, gallium, iron, magnesium, molybdenum, vanadium, zinc, or a combination comprising at least one of the foregoing, preferably molybdenum. The inorganic support includes a zeolite and the silica to alumina molar ratio of the zeolite is 10 to 50, preferably 13 to 30. Desirably, the pH of the catalytic metal solution is greater than or equal to 9, or greater than or equal to 10.

[0005] An aromatization catalyst can be produced by the above-described process.

[0006] A process for aromatization of methane includes reacting the methane in the presence of the above-described aromatization catalyst to obtain an aromatization product comprising benzene, naphthalene, toluene, xylene, ethylbenzene, methyl-naphthalene, or a combination comprising at least one of the foregoing.

[0007] A reaction mixture for aromatization of methane by the above-described process can include the methane and the above-described aromatization catalyst.

[0008] A benzene, naphthalene, toluene, xylene, ethylbenzene, methyl-naphthalene, or a combination comprising at least one of the foregoing can be produced by the above-described process for aromatization of methane, or using the above-described reaction mixture.

BRIEF DESCRIPTION OF DRAWNGS

[0009] The following figures are exemplary embodiments wherein the like elements are numbered alike and which are presented for the purposes of illustrating the exemplary embodiments disclosed herein and not for the purposes of limiting the same.

[0010] The Figure shows the benzene productivity with aromatization reaction time for Examples 1-9.

[0011] The above described and other features are exemplified by the following detailed description, examples, and claims.

DETAILED DESCRIPTION

[0012] Disclosed herein are processes for producing aromatization catalysts and processes for aromatization of methane to obtain an aromatization product comprising benzene, naphthalene, toluene, xylene, ethylbenzene, methyl-naphthalene, or a combination comprising at least one of the foregoing. Desirably, use of the processes described herein using a catalytic metal solution with a pH greater than or equal to 9, or greater than or equal to 10, to produce aromatization catalysts result in a greater benzene productivity during aromatization of methane and a greater stability of the aromatization catalyst as compared to catalysts produced by previous processes. Previous processes for producing aromatization catalysts (i.e., that did not use a catalytic metal solution with a pH greater than or equal to 9, or greater than or equal to 10) suffered from difficulties in achieving high productivity of benzene during aromatization of methane (e.g., difficulties achieving greater than 34 grams of benzene per kilogram of catalyst per hour after an aromatization reaction time of 240 minutes at atmospheric pressure with methane fed at a gas hourly space velocity of 1 ,050 milliliter per gram per hour) and required energy intensive processes for separation of benzene from the other aromatization products. The present processes provide a higher benzene productivity (e.g., equal to or greater than 35 grams of benzene per kilogram of catalyst per hour, or equal to or greater than 40 grams of benzene per kilogram of catalyst per hour after an aromatization reaction time of 240 minutes at atmospheric pressure with methane fed at a gas hourly space velocity of 1,050 mlg^h ¹) and sustain the activity of the aromatization catalyst during aromatization of methane (e.g., a benzene productivity drop of equal to or less than 25% at 240 minutes after the start of aromatization based on the benzene productivity at 60 minutes after the start of aromatization). Thus, decreases in benzene productivity and aromatization catalyst life due to coking can be reduced or offset by the present processes.

[0013] Desirably, the aromatization reaction can be performed at pressures greater than atmospheric pressure while still achieving increased benzene productivity from the use of the aromatization catalyst prepared by the processes according to the present disclosure. In particular, any decrease in benzene productivity associated with an increase in pressure during the aromatization can be offset at least in part by at least one of the greater initial benzene productivity, peak benzene productivity, and the lower drop in aromatization catalyst activity over the aromatization reaction time. The aromatization product obtained at higher pressures (e.g., greater than 100 kilopascals) can be separated more efficiently and with less energy in subsequent separation processes to produce a benzene product with high purity as compared to previous processes operating at atmospheric pressure. For instance, the aromatization products from the processes of the present disclosure can have smaller volumetric flow rates as compared to aromatization products from processes operating at lower pressures. Thus, downstream separation equipment (e.g., compressors, etc.) can be smaller in size and use less energy. For instance, in a process for aromatization of benzene producing 260 kilotons of high purity (e.g., at least 95 weight % benzene, based on the total weight of the benzene product) benzene product per year from aromatization of methane, a total energy can be reduced from 130 megawatts, when the process is at 100 kilopascals, to 80 megawatts, when the process is at 550 kilopascals. Therefore, the processes of the present disclosure can produce greater amounts of benzene in existing aromatization reactors due to the increase productivity, as well as allow for an efficient separation to obtain a high purity benzene product.

[0014] A process for producing an aromatization catalyst can include contacting an inorganic support with a catalytic metal solution with a pH greater than or equal to 9, or greater than or equal to 10, to deposit a catalytic metal onto the inorganic support to obtain the aromatization catalyst and then carburizing the aromatization catalyst. Desirably, an aromatization catalyst produced in such a manner provides greater benzene productivity and a greater stability of the aromatization catalyst during aromatization of methane as compared to aromatization catalysts produced by previous processes (e.g., that do not use a pH of the catalytic metal solution of greater than or equal to 9). Without wishing to be bound by theory, it is believed that in alkaline solutions molybdates are present as monomeric ions (M0O4]^2", which can combine with Bronsted acid sites of the inorganic support (e.g., ZSM-5) to form molybdenum carbide, which can activate the C-H bonds of methane.

[0015] The inorganic support can be calcined prior to the step of contacting the inorganic support with the catalytic metal solution. For example, the inorganic support can be calcined at a temperature of 500°C to 600°C for a time of 2 hours to 10 hours. Calcining the inorganic support can convert the ammonia form of the inorganic support (e.g., ZSM-5) to the hydrogen form.

[0016] The inorganic support can be an inorganic oxide such as zeolite. The zeolite can be at least one of a zeolite Y, zeolite X, mordenite, ZSM-5, HZSM-5, ALPO-5, VPI-5, FSM-16, MCM-22, MCM-41. Desirably, the zeolite is HZSM-5 (i.e., is in the hydrogen form and is acidic). The acidity of the inorganic support (e.g., HZSM-5) can be 1.2 millimoles of hydrogen per gram of inorganic support to 1.5 millimoles of hydrogen per gram of inorganic support. The zeolite can have a silica to alumina molar ratio of 10 to 50, preferably 13 to 30. A pore diameter of the inorganic support can be 5.1 Angstroms (A) to 5.2 Angstroms (A).

[0017] The catalytic metal solution can include the catalytic metal in an amount of 2 weight % (wt. ) to 7 weight , or 3 weight % to 6 weight , based on the weight of the inorganic support. The catalytic metal can include at least one of chromium, cobalt, gallium, iron, magnesium, molybdenum, vanadium, and zinc, preferably the catalytic metal is molybdenum. Desirably, the aromatization catalyst comprises one catalytic metal. The aromatization catalyst can be devoid of silver and rhenium.

[0018] The pH of the catalytic metal solution can be adjusted to the desired pH by a base (e.g., ammonia), an acid, or a combination comprising at least one of the foregoing.

[0019] The inorganic support can be contacted with the catalytic metal solution to penetrate the pores of the inorganic support and react with active sites on the inorganic support. The step of contacting can include soaking the inorganic support in the catalytic metal solution for a period of time of 15 minutes to 120 minutes. The step of contacting can include agitating, mixing, or stirring the inorganic support in the catalytic metal solution. The pH of the catalytic metal solution can be adjusted to the desired pH during the step of contacting the inorganic support with the catalytic metal solution.

[0020] Without wishing to be bound by theory, it is believed that the above-described process for producing an aromatization catalyst enhances the dispersion of the catalytic metal on the inorganic support, which increases the benzene productivity in an aromatization reaction.

[0021] The aromatization catalyst can be dried, calcined, or a combination of at least one of the foregoing before the step of carburizing the aromatization catalyst. For example, the aromatization catalyst can be dried at a temperature of 80°C to 120°C for a time of 10 hours to 20 hours. The aromatization catalyst can be calcined at a temperature of 500°C to 600°C for a time of 10 hours to 20 hours. During the drying and calcining, air can be flowed over the aromatization catalyst. The flowing air can be provided at 20°C to 30°C, have a relative humidity of 5% to 30%, and a velocity of 0.1 to 1 milliliters/second. The calcination step can decompose the molybdenum to the oxide form and migrate the molybdenum oxide to the Bronsted acid sites of the inorganic support.

[0022] The process for producing an aromatization catalyst can include carburizing the aromatization catalyst to activate the catalytic metal. The step of carburizing the aromatization catalyst can include contacting the aromatization catalyst with a carburizing gas at a gas hourly space velocity of 1,000 to 10,000 milliliters gram^-1 hour¹ at a carburization temperature of 25°C to 250°C, and increasing the carburization temperature up to 300°C to 650°C at a rate of 2°C to 10°C per minute. The carburizing gas can include methane, hydrogen, ethane, propane, butane, carbon monoxide, and a combination comprising at least one of the foregoing. A carburizing gas including hydrogen can partially reduce M0O3 to M0O2, which more readily forms molybdenum carbide. Desirably, the carburizing gas includes methane and hydrogen in with a volume ratio of 1:4 to 1 :3 to reduce or mitigate carbon formation during carburization.

[0023] Also included herein is an aromatization catalyst produced by the above- described process.

[0024] Further included is the use of the aromatization catalyst for aromatization of methane. A process for aromatization of methane can include reacting the methane in the presence of the above-described aromatization catalyst to obtain an aromatization product comprising at least one of benzene, naphthalene, toluene, xylene, ethylbenzene, and methyl- naphthalene. Desirably, the process is continuous (i.e., methane is fed into the presence of the aromatization catalyst for a period of time while aromatization product is removed from the presence of the aromatization catalyst during the same period of time, in contrast to a batch process).

[0025] The step of reacting the methane can be at a pressure equal to or greater than 300 kilopascals, or 300 kilopascals to 1,000 kilopascals, preferably 300 kilopascals to 900 kilopascals.

[0026] The methane can be fed to the step of reacting at a gas hourly space velocity of 1,000 to 30,000 milliliters gram^-1 hour¹, or 2,000 to 29,000 milliliters gram^-1 hour¹, preferably 3,000 to 28,000 milliliters gram^"1 hour¹.

[0027] The step of reacting the methane can be at a temperature of 700°C to 850°C, or 700°C to 825°C, preferably 700°C to 800°C. [0028] At least one of carbon dioxide and carbon monoxide can be fed to the step of reacting in an amount of 0.1 volume % to 4 volume , based on the volume of the methane. Without wishing to be bound by theory, it is believed that carbon dioxide, carbon monoxide, or both react with coke precursors to subdue or prevent coke formation on the aromatization catalyst. Thus, decreases in the aromatization catalyst activity and benzene productivity over time during the aromatization reaction can be reduced.

[0029] The benzene productivity can be 40 grams of benzene per kilogram of catalyst per hour (g bnz/kg cat/hr) to 1 ,000 grams of benzene per kilogram of catalyst per hour, or 50 grams of benzene per kilogram of catalyst per hour to 900 grams of benzene per kilogram of catalyst per hour, preferably 60 grams of benzene per kilogram of catalyst per hour to 800 grams of benzene per kilogram of catalyst per hour.

[0030] The peak benzene productivity can be 330 grams of benzene per kilogram of catalyst per hour (g bnz/kg cat/hr) to 1 ,000 grams of benzene per kilogram of catalyst per hour, or 340 grams of benzene per kilogram of catalyst per hour to 900 grams of benzene per kilogram of catalyst per hour, preferably 350 grams of benzene per kilogram of catalyst per hour to 800 grams of benzene per kilogram of catalyst per hour. As used herein, "peak benzene

productivity" refers to the highest benzene productivity over an aromatization reaction time period of at least 240 minutes from the start of the aromatization reaction.

[0031] The process of aromatization of methane can further include compressing the aromatization product and separating the aromatization product to obtain a benzene product.

[0032] The step of separating the aromatization product comprises at least one of an absorption process and a distillation process.

[0033] A benzene production of the process of aromatization of methane can be equal to or greater than 150 kilotons per year, or equal to or greater than 175 kilotons per year, preferably equal to or greater than 200 kilotons per year. For such a process of aromatization of methane, a total energy of the process can be equal to or less than 80 megawatts, or equal to or less than 75 megawatts, preferably equal to or less than 70 megawatts.

[0034] A reaction mixture for aromatization of methane by the above-described process for aromatization of methane can include the methane and the above-described aromatization catalyst. [0035] At least one of benzene, naphthalene, toluene, xylene, ethylbenzene, and methyl- naphthalene can be produced by the above described process for aromatization of methane, or using the above-described reaction mixture.

[0036] This disclosure is further illustrated by the following examples, which are non- limiting.

EXAMPLES

Examples 1-9

[0037] Eight molybdenum/HZSM-5 aromatization catalysts were prepared using various inorganic supports and ammonium hepta molybdate solutions. One aromatization catalyst was produced twice to illustrate its reproducibility. Each aromatization catalyst was contacted with methane in an aromatization reaction to produce benzene. Table 1 summarizes the

aromatization reaction temperature; the pH of a 5 wt.% ammonium hepta molybdate solution used to prepare the aromatization catalysts; the silica to alumina molar ratios (Si/Al ratio) of the catalyst supports; whether carburization was used; benzene productivity expressed as the grams of benzene produced per kilogram of aromatization catalyst per hour (g of bnz/kg of cat/hr); and percent decrease in benzene productivity during the aromatization reaction (as a measure of catalytic activity).

[0038] For aromatization catalyst preparation, 125 grams (g) of HZSM-5 zeolite catalyst support was calcined by placing the HZSM-5 zeolite catalyst support in a muffle furnace under flowing air (25°C, 15% relative humidity, 0.5 milliliters/second velocity) and increasing the temperature 2.5°C per minute until a temperature of 540°C was reached. The total calcination time was 6 hours. Ammonium hepta molybdate salt (13.81 grams) was dissolved in 280 milliliters (ml) of demineralized water at 25 °C to produce an ammonium hepta molybdate solution. The pH of the ammonium hepta molybdate solution was initially 4.5. For Examples 3, 4, and 7-9 the pH was adjusted with dropwise addition of aqueous ammonia (25 wt.% ammonia concentration) until a pH of 9.8 was reached.

[0039] The HZSM-5 zeolite catalyst support was then contacted for 1 hour with the ammonium hepta molybdate solution at 25 °C in a 500 milliliter three-neck round-bottom flask while the ammonium hepta molybdate solution was stirred at 300 rotations per minute. For Examples 3, 4, and 7-9, the aqueous ammonia was added during the stirring until a pH of 9.8 was reached. Then the ammonium hepta molybdate solution was stirred for another 2 hours.

[0040] Next, the flask was placed in a water bath at a temperature of 95 °C and continuously stirred until the water was removed. [0041] The aromatization catalyst was removed from the flask, crushed into a powder, and dried at a temperature of 110°C in an air oven for 16 hours. The aromatization catalyst was then gently ground and stored in a polypropylene bottle until the aromatization catalyst was calcined.

[0042] The aromatization catalyst was calcined by heating the aromatization catalyst starting from room temperature to 540°C at a rate of 2.5°C per minute in a calcination furnace in flowing air (25°C, 15% relative humidity, 0.5 milliliters/second velocity) and calcined at 540°C for 16 hours. After calcination the aromatization catalyst was cooled to room temperature in flowing air (25°C, 15% relative humidity, 0.5 milliliters/second velocity).

[0043] Carburization of the aromatization catalysts was carried out by feeding 20 volume % methane and 80 volume% hydrogen, based on the total volume of the methane and hydrogen, at a gas hourly space velocity of 1,050 milliliters gram^-1 hour¹ (mlg^h ¹) into a quartz reactor with a 9 millimeter (mm) internal diameter containing 2 grams of the aromatization catalyst. The temperature in the quartz reactor was initially 50°C and then increased until the carburization temperature reached 650°C, using a heating rate of 3°C per minute. The 650°C carburization temperature was maintained for 15 minutes.

[0044] Inductively coupled plasma mass spectrometry (ICP) was used to measure the molybdenum content in the catalyst before and after the carburization. For all the Examples, the molybdenum content was 4.8 wt. % before carburization. For all the Examples, the molybdenum content was 4.8 wt. % after carburization.

[0045] For the aromatization of methane, the methane was fed at a gas hourly space velocity of 1,050 milliliter per gram per hour (mlg^h ¹) into the fixed bed quartz reactor, which was inside a furnace. The reactions were carried out at atmospheric pressure.

Table 1

*As used herein, peak benzene productivity is the highest grams of benzene per kilograms of catalyst per hour (g benz/kg cat/hr) during the aromatization reaction (e.g., @ 60 minutes). **As used herein, benzene productivity drop is calculated based on the formula: (1- Benzene productivity @ 240 minutes/Peak benzene productivity *100).

[0046] Examples 7 and 8 (are repeat experiments at the same conditions) resulted in the highest benzene productivity and most stable activity of the catalyst. As can be seen in the Table 1 and the Figure, Examples 7 and 8 showed the lowest benzene productivity drop.

Examples 10-22

[0047] The aromatization catalyst prepared in Example 7 was tested in thirteen aromatization reactions with various gas hourly space velocities (GHSV) of methane, reaction temperatures, and reaction pressures (kilopascals (kPa)). The aromatization reaction conditions and results are summarized in Table 2.

Table 2

*As used herein, peak benzene productivity is the highest grams of benzene per kilograms of catalyst per hour (g bnz/kg cat/hr) during the aromatization reaction.

***As used herein, benzene productivity drop is calculated based on the formula: (1- Benzene productivity @ 60 minutes/Peak benzene productivity *100).

[0048] The results in Table 2 surprisingly show that an increase in GHSV (which reduces the residence time of the gas) increases the benzene productivity. In particular, the results indicate that benzene productivity was highest when methane was fed at a GHSV of 25,000 mlg^h^"1, the aromatization reaction temperature was at 820°C, and the pressure was at 500 kPa.

Examples 23-26

[0049] For Examples 23-26, the aromatization catalysts were prepared as described in Examples 3, 4, and 7-9 above, using catalyst supports with various Si/Al ratios. The aromatization reaction conditions and results are summarized in Table 3. Table 3

***As used in herein, benzene productivity drop is calculated based on the formula: (1- Benzene productivity @ 60 min/Peak benzene productivity *100).

[0050] As can be seen in the results of Table 3, all the test catalyst supports provided peak benzene productivities over 450 grams per kilogram of catalyst per hour. However, the benzene productivity dropped after 1 hour as expected due to the high 820°C reaction temperature.

[0051] As shown herein, the aromatization reaction can be performed at pressures greater than atmospheric pressure while still achieving increased benzene productivity from the use of the aromatization catalyst prepared by processes according to the present disclosure. Thus, decreased selectivity for benzene production associated with an increase in pressure can be offset at least in part by the processes for preparing the aromatization catalyst and the increase in GHSV of the methane fed to the aromatization reaction.

[0052] In addition, decreases in benzene productivity and aromatization catalyst life due to coking can be reduced or offset by the present processes. Thus, the processes provided can produce greater amounts of benzene in existing aromatization reactors due to the increased productivity, as well as allow for an efficient separation of a benzene product with higher purity due to the higher pressure of the aromatization product being fed to subsequent compression and separation processes.

[0053] The compositions and methods disclosed herein are further illustrated by the following aspects, which are non-limiting:

[0054] Aspect 1 : A process for producing an aromatization catalyst comprising contacting an inorganic support with a catalytic metal solution to deposit a catalytic metal onto the inorganic support to obtain the aromatization catalyst, and carburizing the aromatization catalyst, wherein the catalytic metal comprises chromium, cobalt, gallium, iron, magnesium, molybdenum, vanadium, zinc, or a combination comprising at least one of the foregoing, preferably molybdenum, and wherein the inorganic support comprises a zeolite, and wherein a silica to alumina molar ratio of the zeolite is 10 to 50, preferably 13 to 30, and wherein the pH of the catalytic metal solution is greater than or equal to 9, or greater than or equal to 10.

[0055] Aspect 2: The process of Aspect 1, wherein the catalytic metal solution comprises the catalytic metal in an amount of 2 wt. % to 7 wt. , or 3 wt. % to 6 wt. %, based on the weight of the inorganic support.

[0056] Aspect 3: The process of any one or more of the preceding aspects, wherein the zeolite comprises zeolite Y, zeolite X, mordenite, ZSM-5, HZSM-5, ALPO-5, VPI-5, FSM-16, MCM-22, MCM-41, or any combination comprising at least one of the foregoing, preferably HZSM-5.

[0057] Aspect 4: The process of any one or more of the preceding aspects, wherein the contacting comprises soaking the inorganic support in the catalytic metal solution for a period of time of 15 minutes to 120 minutes.

[0058] Aspect 5: The process of any one or more of the preceding aspects, where carburizing the aromatization catalyst comprises contacting the aromatization catalyst with a carburizing gas at a gas hourly space velocity of 1,000 to 10,000 milliliters gram^-1 hour¹ at a carburization temperature of 25 °C to 250°C, and increasing the carburization temperature up to 300°C to 650°C at a rate of 2°C to 10°C per minute.

[0059] Aspect 6: The process of any one or more of the preceding aspects, wherein the aromatization catalyst comprises one catalytic metal.

[0060] Aspect 7: The process of any one or more of the preceding aspects, wherein the aromatization catalyst is devoid of silver and rhenium.

[0061] Aspect 8: An aromatization catalyst produced by the process of any one or more of the preceding aspects.

[0062] Aspect 9: A process for aromatization of methane comprising reacting the methane in the presence of the aromatization catalyst of Aspect 8 to obtain an aromatization product comprising benzene, naphthalene, toluene, xylene, ethylbenzene, methyl-naphthalene, or a combination comprising at least one of the foregoing.

[0063] Aspect 10: The process of Aspect 9, wherein reacting the methane is at a pressure equal to or greater than 300 kilopascals, or 300 kilopascals to 1,000 kilopascals, preferably 300 kilopascals to 900 kilopascals.

[0064] Aspect 11 : The process of any one or more of Aspects 9-10, wherein the methane is fed to the step of reacting at a gas hourly space velocity of 1 ,000 to 30,000 milliliters gram^-1 hour ¹, or 2,000 to 29,000 milliliters gram^-1 hour ¹, preferably 3,000 to 28,000 milliliters gram^-1 hour ¹. [0065] Aspect 12: The process of any one or more of Aspects 9-11, wherein reacting the methane is at a temperature of 700°C to 850°C, or 700°C to 825°C, preferably 700°C to 800°C.

[0066] Aspect 13: The process of any one or more of Aspects 9-12, wherein the process is continuous.

[0067] Aspect 14: The process of any one or more of Aspects 9-13, wherein a benzene productivity is 35 grams of benzene per kilogram of catalyst per hour to 1,000 grams of benzene per kilogram of catalyst per hour, or 40 grams of benzene per kilogram of catalyst per hour to 900 grams of benzene per kilogram of catalyst per hour, preferably 50 grams of benzene per kilogram of catalyst per hour to 800 grams of benzene per kilogram of catalyst per hour.

[0068] Aspect 15: The process of any one or more of Aspects 9-14, further comprising compressing the aromatization product and separating the aromatization product to obtain a benzene product.

[0069] Aspect 16: The process of Aspect 15, wherein separating the aromatization product comprises at least one of an absorption process and a distillation process.

[0070] Aspect 17: The process of any one or more of Aspects 9-16, wherein a benzene production of the process is equal to or greater than 150 kilotons per year, or equal to or greater than 175 kilotons per year, preferably equal to or greater than 260 kilotons per year.

[0071] Aspect 18: The process of Aspect 17, wherein a total energy of the process is equal to or less than 80 megawatts, or equal to or less than 75 megawatts, preferably equal to or less than 70 megawatts.

[0072] Aspect 19: A reaction mixture for aromatization of methane by the process of any one or more of Aspects 9-18, wherein the reaction mixture comprises the methane; and the aromatization catalyst of Aspect 8.

[0073] Aspect 20: A benzene, naphthalene, toluene, xylene, ethylbenzene, methyl- naphthalene, or a combination comprising at least one of the foregoing produced by the process of any one or more of Aspects 9-18, or using the reaction mixture of Aspect 19.

[0074] Aspect 21 : The process of any one or more of Aspects 1-7, wherein a benzene productivity is 35 grams of benzene per kilogram of catalyst per hour to 1,000 grams of benzene per kilogram of catalyst per hour, or 40 grams of benzene per kilogram of catalyst per hour to 900 grams of benzene per kilogram of catalyst per hour, preferably 50 grams of benzene per kilogram of catalyst per hour to 800 grams of benzene per kilogram of catalyst per hour, after an aromatization reaction time of 240 minutes at atmospheric pressure with methane fed at a gas hourly space velocity of 1,050 mlg^h ¹. [0075] Aspect 22: The process of any one or more of Aspects 1-7 or Aspect 21, wherein a peak benzene productivity is 330 grams of benzene per kilogram of catalyst per hour to 1,000 grams of benzene per kilogram of catalyst per hour, or 340 grams of benzene per kilogram of catalyst per hour to 900 grams of benzene per kilogram of catalyst per hour, preferably 350 grams of benzene per kilogram of catalyst per hour to 800 grams of benzene per kilogram of catalyst per hour.

[0076] In general, the invention may alternately comprise, consist of, or consist essentially of, any appropriate components herein disclosed. The invention may additionally, or alternatively, be formulated so as to be devoid, or substantially free, of any components, materials, ingredients, adjuvants or species used in the prior art compositions or that are otherwise not necessary to the achievement of the function and/or objectives of the present invention. The endpoints of all ranges directed to the same component or property are inclusive and independently combinable (e.g., ranges of "less than or equal to 25 wt , or 5 wt to 20 wt ," is inclusive of the endpoints and all intermediate values of the ranges of "5 wt to 25 wt ," etc.). Disclosure of a narrower range or more specific group in addition to a broader range is not a disclaimer of the broader range or larger group. "Combination" is inclusive of blends, mixtures, alloys, reaction products, and the like. Furthermore, the terms "first," "second," and the like, herein do not denote any order, quantity, or importance, but rather are used to denote one element from another. The terms "a" and "an" and "the" herein do not denote a limitation of quantity, and are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. "Or" means "and/or." The suffix "(s)" as used herein is intended to include both the singular and the plural of the term that it modifies, thereby including one or more of that term (e.g., the film(s) includes one or more films). Reference throughout the specification to "one embodiment", "another embodiment", "an embodiment", and so forth, means that a particular element (e.g., feature, structure, and/or characteristic) described in connection with the embodiment is included in at least one embodiment described herein, and may or may not be present in other embodiments. In addition, it is to be understood that the described elements may be combined in any suitable manner in the various embodiments.

[0077] The modifier "about" used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., includes the degree of error associated with measurement of the particular quantity). The notation "+ 10%" means that the indicated measurement can be from an amount that is minus 10% to an amount that is plus 10% of the stated value. The terms "front", "back", "bottom", and/or "top" are used herein, unless otherwise noted, merely for convenience of description, and are not limited to any one position or spatial orientation. "Optional" or "optionally" means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where the event occurs and instances where it does not. Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this invention belongs. A "combination" is inclusive of blends, mixtures, alloys, reaction products, and the like.

[0078] All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, if a term in the present application contradicts or conflicts with a term in the incorporated reference, the term from the present application takes precedence over the conflicting term from the incorporated reference.

[0079] While particular embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are or may be presently unforeseen may arise to applicants or others skilled in the art. Accordingly, the appended claims as filed and as they may be amended are intended to embrace all such alternatives, modifications variations, improvements, and substantial equivalents.

[0080] What is claimed is:

Claims

1. A process for producing an aromatization catalyst comprising:

contacting an inorganic support with a catalytic metal solution to deposit a catalytic metal onto the inorganic support to obtain the aromatization catalyst; and

carburizing the aromatization catalyst,

wherein the catalytic metal comprises chromium, cobalt, gallium, iron, magnesium, molybdenum, vanadium, zinc, or a combination comprising at least one of the foregoing, preferably molybdenum, and

wherein the inorganic support comprises a zeolite, and

wherein a silica to alumina molar ratio of the zeolite is 10 to 50, preferably 13 to 30, and wherein the pH of the catalytic metal solution is greater than or equal to 9, or greater than or equal to 10.

2. The process of Claim 1 , wherein the catalytic metal solution comprises the catalytic metal in an amount of 2 wt. % to 7 wt. , or 3 wt. % to 6 wt. , based on the weight of the inorganic support.

3. The process of any one or more of the preceding claims, wherein the zeolite comprises zeolite Y, zeolite X, mordenite, ZSM-5, HZSM-5, ALPO-5, VPI-5, FSM-16, MCM- 22, MCM-41, or any combination comprising at least one of the foregoing, preferably HZSM-5.

4. The process of any one or more of the preceding claims, wherein the contacting comprises soaking the inorganic support in the catalytic metal solution for a period of time of 15 minutes to 120 minutes.

5. The process of any one or more of the preceding claims, where carburizing the aromatization catalyst comprises contacting the aromatization catalyst with a carburizing gas at a gas hourly space velocity of 1,000 to 10,000 milliliters gram^-1 hour¹ at a carburization temperature of 25°C to 250°C, and increasing the carburization temperature up to 300°C to 650°C at a rate of 2°C to 10°C per minute.

6. The process of any one or more of the preceding claims, wherein the

aromatization catalyst comprises one catalytic metal.

7. The process of any one or more of the preceding claims, wherein the aromatization catalyst is devoid of silver and rhenium.

8. An aromatization catalyst produced by the process of any one or more of the preceding claims.

9. A process for aromatization of methane comprising:

reacting the methane in the presence of the aromatization catalyst of Claim 8 to obtain an aromatization product comprising benzene, naphthalene, toluene, xylene, ethylbenzene, methyl- naphthalene, or a combination comprising at least one of the foregoing.

10. The process of Claim 9, wherein reacting the methane is at a pressure equal to or greater than 300 kilopascals, or 300 kilopascals to 1,000 kilopascals, preferably 300 kilopascals to 900 kilopascals.

11. The process of any one or more of Claims 9-10, wherein the methane is fed to the step of reacting at a gas hourly space velocity of 1,000 to 30,000 milliliters gram^-1 hour ¹, or 2,000 to 29,000 milliliters gram^-1 hour¹, preferably 3,000 to 28,000 milliliters gram^-1 hour¹.

12. The process of any one or more of Claims 9-11, wherein reacting the methane is at a temperature of 700°C to 850°C, or 700°C to 825°C, preferably 700°C to 800°C.

13. The process of any one or more of Claims 9-12, wherein the process is continuous.

14. The process of any one or more of Claims 9-13, wherein a benzene productivity is 35 grams of benzene per kilogram of catalyst per hour to 1,000 grams of benzene per kilogram of catalyst per hour, or 40 grams of benzene per kilogram of catalyst per hour to 900 grams of benzene per kilogram of catalyst per hour, preferably 50 grams of benzene per kilogram of catalyst per hour to 800 grams of benzene per kilogram of catalyst per hour.

15. The process of any one or more of Claims 9-14, further comprising compressing the aromatization product and separating the aromatization product to obtain a benzene product.

16. The process of Claim 15, wherein separating the aromatization product comprises at least one of an absorption process and a distillation process.

17. The process of any one or more of Claims 9-16, wherein a benzene production of the process is equal to or greater than 150 kilotons per year, or equal to or greater than 175 kilotons per year, preferably equal to or greater than 260 kilotons per year.

18. The process of Claim 17, wherein a total energy of the process is equal to or less than 80 megawatts, or equal to or less than 75 megawatts, preferably equal to or less than 70 megawatts.

19. A reaction mixture for aromatization of methane by the process of any one or more of Claims 9-18, wherein the reaction mixture comprises:

the methane; and

the aromatization catalyst of Claim 8.

20. A benzene, naphthalene, toluene, xylene, ethylbenzene, methyl-naphthalene, or a combination comprising at least one of the foregoing produced by the process of any one or more of Claims 9-18, or using the reaction mixture of Claim 19.