CN101321717B - Production of aromatic hydrocarbons from methane - Google Patents

Abstract

In a process for converting methane to higher hydrocarbons including aromatic hydrocarbons, a feed containing methane is contacted with a dehydrocyclization catalyst in a reaction zone under conditions effective to convert said methane to aromatic hydrocarbons. A first portion of the catalyst is transferred from the reaction zone to a heating zone, where the first catalyst portion is heated by contacting the catalyst with hot combustion gases generated by burning a supplemental source of fuel. The heated first catalyst portion is then returned to the reaction zone.

Description

By the methane production aromatic hydrocarbon

Technical field

The present invention relates to from methane, particularly from the method for gas production aromatic hydrocarbon. Background of invention

Aromatic hydrocarbon, particularly benzene, toluene, ethylbenzene and YLENE are important daily chemical in petrochemical industry.At present, aromatic substance is produced from the raw material based on oil through the whole bag of tricks mostly usually, comprises CR and catalytic cracking.Yet,, more and more need seek the alternative source of aromatic hydrocarbon because the supply of the world of petroleum reduces.

A kind of alternative source of possible aromatic hydrocarbon is a methane, and it is the staple of Sweet natural gas and biogas.The Sweet natural gas that the world saving of Sweet natural gas improves constantly and finds at present is more than oil.Because with the relevant problem of big volume natural gas transportation, the Sweet natural gas that great majority are produced with oil is burnt and is slatterned, particularly in remote districts.Therefore contained alkane is the method for attractive especially upgrading Sweet natural gas to the conversion of higher hydrocarbons such as aromatic substance more directly in the Sweet natural gas, as long as the technical barrier of following can be able to overcome.

It is that the method for liquid hydrocarbon comprises being synthetic gas with methane conversion at first, H that great majority are used for methane conversion ₂Blend with CO.The production of synthetic gas is expensive and energy-intensive; The route that therefore need not generate synthetic gas is preferred.

For methane conversion has been proposed many alternate methods for higher hydrocarbons more.A kind of such method comprises that methyl hydride catalyzed oxidative coupling becomes alkene, and then this olefin catalytic is converted into liquefied hydrocarbon, comprises aromatic hydrocarbon.For example, United States Patent(USP) No. 5,336,825 disclose and have been used for the two-stage process that methane oxidation is converted into the hydro carbons of the gasoline-range that comprises aromatic hydrocarbon.In the first step, with the promoted alkaline earth metal oxide catalyzer of rare earth metal, in the presence of free oxygen, making methane conversion is ethene and a spot of C under 500 ℃-1000 ℃ temperature ₃And C ₄Alkene.On the acidic solid catalyst of the five yuan of supersiliceous zeolites (pentasil zeolite) that contain high silicon dioxide, make then the ethene that forms in the first step and more higher alkene be converted into the liquefied hydrocarbon of gasoline-range.

Yet the problem that these oxidative coupling methods exist is that they comprise the height heat release and dangerous potentially methyl hydride combustion reacts and they produce the oxycarbide of a large amount of environment sensitives.

Methane also becomes the approach of more higher hydrocarbons, particularly ethene, benzene and naphthalene to propose the methane upgrading as being used for through the dehydroaromatizationof of high temperature reduction coupling.Thereby; For example, United States Patent(USP) No. 4,727; 206 disclose a kind of method that is used to produce the liquid that is rich in aromatic hydrocarbon; This method do not have oxygen to exist and 600 ℃-800 ℃ temperature under, carry out through methane is contacted with the catalyst composition that contains silico-aluminate, the silicon-dioxide of said silico-aluminate and the mol ratio of aluminum oxide were at least 5: 1 and supported (i) gallium or its compound and (ii) from metal or its compound of periodic table of elements VIIB family.

In addition; United States Patent(USP) No. 5,026,937 disclose a kind of aromatization method that is used for methane; It comprises making and contains the step that under conversion condition, gets into reaction zone above the incoming flow of 0.5mol% hydrogen and 50mol% methane; This reaction zone has at least one solid catalyst bed that comprises ZSM-5 and phosphorus-containing alumina, and said conversion condition comprises 550 ℃-750 ℃ temperature, less than the pressure and the 400-7 of 10 bar absolute pressures (1000kPaa), 500hr ^-1Gas hourly space velocity.This product elute it is said and comprises methane, hydrogen, 3mol%C at least ₂Hydrocarbon and 5mol%C at least ₆-C ₈Aromatic hydrocarbon.Removing C ₄After the condensation that+level is divided, propose with hydrogen in the low temperature technique separated product elute and light hydrocarbon (methane, ethane, ethene etc.).

United States Patent(USP) Nos. 6; 239; 057 and 6,426,442 disclose the for example method of benzene of a kind of hydrocarbon from low carbon number hydrocarbon such as methane production higher carbon number; It carries out through this low carbon number hydrocarbon is contacted with the catalyzer that contains porous support such as ZSM-5, on this porous support, is dispersed with rhenium and promoter metals such as iron, cobalt, vanadium, manganese, molybdenum, tungsten or its mixture.In charging, add CO or CO ₂It is said the stability of the productive rate and the catalyzer that have improved benzene.

Yet the suggestion of existing dehydroaromatizationof to methane has low selectivity to aromatic substance usually, and the co-fed that possibly need expensive additive is to improve selective aromatics.In addition, any reductive coupling method produces a large amount of hydrogen, therefore for economic feasibility, need effectively utilize the approach of this hydrogen by product.Because natural-gas field often is in remote districts, effectively the hydrogen utilization can bring sizable challenge.

Another uses reductive coupling is that the more related problem of higher hydrocarbon is a large amount of heat to be provided to reaction with the methane upgrading.Therefore not only this method is highly to absorb heat, and this to be reflected at the thermodynamics aspect also be restricted.Therefore, if supplemental heat is not provided, can reduce temperature of reaction to being enough to greatly to reduce speed of response and total thermodynamic change rate by the caused cooling effect of reaction with certain mode.Proposed several different methods and heat is provided, but proved that up to now the method that is proposed is all satisfactory by halves in order to aromizing to methane.

For example, a kind of known to the methane aromatizing process method of reaction heat to be provided be the heat exchange fluid that flows through reaction zone through utilization, and its catalyzer in reaction zone provides indirect thermal.Yet, the inefficient often and destruction that causes the catalyst stream in the on-fixed bed bioreactor of the method for this heat exchange.

Also known to using more than one tactic reaction zone, and be combined in that the reheat reactant comes to the methane aromatizing process reaction heat to be provided between the reaction zone.In this inter-stage reheat, will be heated to the required temperature in of the catalyst bed in second downstream from the reactor effluent of first catalyst bed.

A kind of method of inter-stage reheat comprises the use indirect heat exchange, wherein makes the elute from upstream reaction zone before supplying with subsequent reaction zone, pass through heat exchanger.The high temperature fluid that uses in this indirect heat exchange method can be high-temperature steam, combustion gases, high-temperature technology materials flow or any high temperature fluid that other can be easy to obtain.The method of this inter-stage heating is the diluting reaction thing not, but really this system is produced a constant pressure drop and reactant is exposed under undesirable high temperature.

For example, Russ P No.2,135,441 disclose a kind of being used for is the method for heavy hydrocarbon more with methane conversion, wherein with methane and the C of 5wt% at least ₃+ hydrocarbon mixes such as benzene, then with comprise oxidisability and under the methane dividing potential drop of 0.05MPa at least and at least 440 ℃ temperature, contact greater than the catalyzer of 0 metal platinum.This method uses the inter-stage reheat in multiple-stage reactor system, to implement through indirect heat exchange.The hydrogen that generates in this method is contacted with carbon oxides to produce extra methane, after removing the water of common generation, can it be joined in the methane feed.The product of methane conversion is C ₂-C ₄Gas phase and C ₅+ liquid phase, however according to embodiment, compare having a net increase of long very little (less than 5wt%) or not having a net increase of length of aromatic ring with charging.

The method of another kind of inter-stage heating is an oxidation reheat method, and this method comprises sneaks into reactant and with the hydrogen selective oxidation that generates in the aromatization process with the oxygen of controlled quatity.Compare with perhaps oxidation that more valuable charging and product hydrocarbon are burnt devastatingly, this oxidation realizes that in the presence of catalyzer this catalyst selectivity ground has promoted the oxidation of hydrogen.Yet, this reaction produced can be to aromatized catalyst harmful and can with methane reaction to form the steam of hydrogen and carbon monoxide.In addition, owing to use second kind of catalyst for selective oxidation, this method has extra complicacy and cost.

Provide the alternative route of reaction heat true below utilizing to the reductive coupling process, this catalyzer generation coke when aromatization carries out.These coke little by little make catalyst deactivation, therefore this catalyzer are regenerated to remove coke and to make this reactivation of catalyst times without number.This regeneration (comprise this catalyzer is contacted with oxygen-containing gas) is the height heat release, therefore can be used as the source of the sensible heat of whole process.This method discloses in International Patent Publication No. WO 03/000826, and wherein catalyst for dehydroaromatizationof circulates between reactor assembly and regenerator system, wherein makes this catalyzer (comprise O with different regeneration gass in the different moment ₂, H ₂And H ₂O) contact is so that the different piece regeneration of catalyzer.The percentage of the catalyzer that control contacts with each regeneration gas is under the thermal equilibrium state to keep this reactor assembly and regeneration system rapidly.This reactor assembly is included in the fluidized-bed of the catalyzer in the riser reactor, and this regeneration system rapidly comprises second fluidized-bed of the catalyzer that remains in the ebullated bed reactor.

Yet use process catalyst regeneration step with the problem that the method that reaction heat is provided exists to be: in regenerative process, need catalyzer be heated to the temperature that is much higher than the goal response temperature, this causes catalyst degradation that quickens and the catalyst life that therefore reduces.In addition, in order to keep thermal equilibrium, this method needs STRENGTH ON COKE rather than to the high selectivity of required aromatic products.

Therefore need improved aromizing that the method for reaction heat is provided to methane. Summary of the invention

On the one hand, the present invention relates to be used for methane conversion is the method that comprises the more higher hydrocarbon of aromatic hydrocarbon, and this method comprises: (a) making the charging that comprises methane and dehydrocyclization catalyst is to contact under the condition of aromatic hydrocarbon effectively making said methane conversion in reaction zone; (b) first part with said catalyzer is transferred to the heating zone from this reaction zone; (c) in this heating zone,, this catalyzer heats this first catalyst member through being contacted with the hot combustion gas that produces through the combustion fuel supplementary source; First catalyst member that (d) will heat returns to this reaction zone.

Aptly, said first catalyst member is directly contacted with said fuel source.Perhaps, with isolating combustion zone, said heating zone in the said fuel source of burning and the combustion gases that will in this combustion zone, produce supply with this heating zone.

Aptly, said fuel refreshment source comprises hydrocarbon and/or hydrogen.

When this fuel refreshment source comprised hydrocarbon, this hydrocarbon is methane preferably, and said fuel refreshment source preferably includes the part of the charging of contact in (a).Aptly, this hydrocarbon fuel of burning and is used for producing other hydrocarbon product and/or fuel with this synthetic gas aptly producing synthetic gas in oxygen-lean atmosphere.

When this fuel refreshment source comprised hydrogen, said fuel comprised the hydrogen as the by product generation of said contact (a).

Aptly, prolong said heating zone and apply heat to said first catalyst member in the positions that a plurality of length along this heating zone are separated.In one embodiment, basically all postcombustions are offered an end of this heating zone, and in the position of said a plurality of separations oxygen-containing gas is increased ground (incrementally) gradually and offer said heating zone.In another embodiment, basically all oxygen-containing gass are offered an end of this heating zone, and this postcombustion is offered said heating zone with increasing gradually in the position of said a plurality of separations.In other embodiment, said hot combustion gas with isolating combustion zone, said heating zone in produce and offer the position of said a plurality of separations.

Preferably; This method also comprises: the second section of this catalyzer is transferred to and isolating breeding blanket, said heating zone, and said second catalyst member is contacted to remove the coke that at least a portion is produced by said contact (a) with regeneration gas in said breeding blanket.

Aptly, the temperature of this breeding blanket is equal to or less than the temperature of this reaction zone.

On the other hand; The present invention relates to be used for methane conversion is the method that comprises the more higher hydrocarbon of aromatic hydrocarbon, and this method comprises: (a) making the charging that comprises methane and dehydrocyclization catalyst is to contact under the condition of aromatic hydrocarbon effectively making said methane conversion in reaction zone; (b) first part with said catalyzer is transferred to the heating zone from this reaction zone; (c) in this heating zone,, this catalyzer heats this first catalyst member through directly being contacted with the hot combustion gas that produces through the combustion fuel supplementary source; First catalyst member that (d) will heat returns to this reaction zone; (e) second section with said catalyzer is transferred to and isolating breeding blanket, said heating zone from this reaction zone; (f) under the condition of effectively removing coke at least in part, said second catalyst member is contacted said breeding blanket with regeneration gas from said second catalyst member; (g) this regenerated second catalyst member is returned to this reaction zone.

Aptly, carry out said transfer (b) and (e) and said sending back to (d) and (g) continuously.

Aptly; Said reaction zone comprises vertically arranged sedimentation bed (settling bed) reactor drum; Wherein said charging gets into this reactor drum near the bottom of this reactor drum or its, and at the top of this reactor drum or near first catalyst member that will heat it and regenerated second catalyst member return to this reactor drum.Aptly, in (b), take out said first and second catalyst members near the bottom of this reactor drum or its.Aptly, perhaps near it said aromatic hydrocarbon is reclaimed from reactor drum at the top of this reactor drum.

Term as used herein " dehydrocyclization catalyst " is intended to not only comprise activity of such catalysts component (one or more), also comprises any inert solid that being used for of except that this active ingredient (one or more), possibly existing improved the physicals of this catalyzer and/or helped to conduct heat. The accompanying drawing summary

Fig. 1 is dehydrocyclization reactor drum and the synoptic diagram of catalyzer reheater according to the first embodiment of the present invention.

Fig. 2 is the dehydrocyclization reactor drum of second embodiment according to the present invention and the synoptic diagram of catalyzer reheater and catalyst regenerator.

Fig. 3 is the synoptic diagram of the multiple fluidized-bed dehydrocyclization reactor drum of third embodiment according to the present invention.

Fig. 4 is with the synoptic diagram that is used for the catalyzer lifting gear that first, second uses with the riser tube of the 3rd embodiment of the present invention.

Fig. 5 compares the temperature distribution of stack gas and the temperature distribution of Different Diameter to the position that at diameter is the catalyst particles intragranular of 3650 μ m to being through when this riser tube base burning fuel provides when heating and all heat in riser tube.

Fig. 6 compares the temperature distribution of stack gas and the temperature distribution of Different Diameter to the position that at diameter is the catalyst particles intragranular of 3650 μ m to when heating in riser tube and through when the spaced-apart locations place combustion fuel along this riser tube length provides hot. The detailed description of embodiment

Term as used herein " more higher hydrocarbon " is meant: each molecule has the hydrocarbon of an above carbon atom; Each molecule has the oxygenatedchemicals of at least one carbon atom, for example ethane, ethene, propane, propylene, benzene,toluene,xylene, naphthalene and/or methylnaphthalene; And/or comprise the organic cpds of at least one carbon atom and at least one non-hydrogen atom, for example methyl alcohol, ethanol, methylamine and/or ethamine.

Term as used herein " aromatic hydrocarbon " is meant the molecule that comprises one or more aromatic rings.The instance of aromatic hydrocarbon is benzene,toluene,xylene, naphthalene and methylnaphthalene.

Term as used herein " moving-bed " reactor drum is meant such zone or container: wherein the desired speed of dilution phase pneumatic transport that makes superficial gas velocity (U) be lower than solid particulate that contacts of solid and air-flow is lower than 95% with the voidage that keeps Solid Bed.Moving-burden bed reactor can be operated under some flow states, comprises sedimentation or moving packed bed state (U＜U _Mf), boiling state (U _Mf＜U＜U _Mb), turbulent state (U _Mb＜U＜U _c), transition and turbulent flow fluidized state (U _c＜U＜U _Tr), and fast fluidized regime (U＞U _Tr).These different fluidized states are for example, Kunii, D., Levenspiel; O., the chapter 3 of Fluidization Engineering, the 2nd edition, Butterworth-Heinemann; Boston, 1991 and Walas, S.M., the chapter 6 of Chemical Process Equipment; Butterworth-Heinemann, Boston is described in 1990.

Term as used herein " sedimentation bed " is meant such zone or container: wherein particulate and air-flow contact at least a portion of reaction zone and make superficial gas velocity (U) be lower than to make the desired minimum velocity of this solid particulate fluidisation, minimum fluidization velocity (U _Mf), U＜U _Mf, and/or be higher than under the speed of this minimum fluidization velocity operation simultaneously through use inside reactor factor (internals) make gas and/or solid performance (forming or the like) like temperature, gas or solid this reactor beds axially on the maintenance gradient so that gas-solid back-mixing minimize.The chapter 3 that for example is described in " Fluidization Engineering " of minimum fluidization velocity, D.Kunii and O.Levenspiel, the 2nd edition; Butterworth-Heinemann, Boston, 1991 with the chapter 6 of " Chemical Process Equipment "; S.M.Walas, Butterworth-Heinemann, Boston; Provide in 1990, its whole introducing is for reference.

Term as used herein " fluidized-bed " reactor drum is meant such zone or container: wherein contacting of solid and air-flow makes that superficial gas velocity (U) is enough to the solid particulate fluidisation (that is, is higher than minimum fluidization velocity U _Mf) and the desired speed of dilution phase pneumatic transport that is lower than solid particulate be lower than 95% with the voidage that keeps Solid Bed.Term as used herein " cascade fluidized-bed " be meant the arranged in series of each fluidized-bed make when solid or gas when a fluidized-bed is fallen another fluidized-bed this gas and/or solid performance (as, temperature, gas or solid composition, pressure or the like) have a gradient.Provide in Kunii that more than for example, points out about the chapters and sections of minimum fluidization velocity and the Walas publication.

Term as used herein " riser tube " reactor drum is meant and in fast fluidized or pneumatic transport fluidisation state, is used for solid make progress the only zone or the container (like, vertical cylindrical pipe) of (net upwards) transmission.Fast fluidized and pneumatic conveying flow state are characterised in that superficial gas velocity (U) is greater than transmission speed (U _Tr).Fast fluidized and pneumatic conveying flow state also are described in Kunii set forth above and Walas publication.

The present invention provides the method for production aromatic hydrocarbon, and this method comprises methane (common and H through making ₂, CO and/or CO ₂Raw material together) contacts in reaction zone with dehydrocyclization catalyst under the condition that effectively with this methane conversion is aromatic hydrocarbon and hydrogen and carries out.As discussed above; This dehydrocyclization reaction is absorbed heat; And the present invention provides the method that is used for providing to reaction heat as follows: a part of taking out this catalyzer from reaction zone; In the heating zone, adopt this catalyst member of hot combustion gas heating that produces through the combustion fuel supplementary source, the catalyst member with heating returns to this reaction zone then.

In addition, the present invention provides the method for use as the hydrogen of the by product generation of this dehydrocyclization reaction, and the method that at least a portion of this hydrogen is converted into more valuable product especially is provided. Raw material

Any raw material that comprises methane may be used to method of the present invention, but generally speaking the inventive method is intended to use gas material.Other raw material that contains methane that is fit to comprises those from obtaining such as coal seam, garbage loading embeading thing, agricultural or sources such as urban waste fermentation and/or refinery's air-flow.

The raw material such as the Sweet natural gas that contain methane also contain carbonic acid gas and ethane usually except methane.The ethane that possibly be present in the charging can be converted into desired aromatic products certainly with other aliphatic hydrocrbon in the dehydrocyclization step.In addition, as the following that kind that will discuss, can be in the dehydrocyclization step directly, or make carbonic acid gas be converted into useful aromatic products indirectly through in hydrogen discharge (hydrogenrejection) step, being converted into methane and/or ethane.

Nitrogen and/or sulphur impurity also are present in the materials flow that contains methane usually, before this materials flow is used for method of the present invention, can removes above-mentioned impurity or be reduced to low levels.In one embodiment, the charging of sending into the dehydrocyclization step comprise separately less than 100ppm, for example less than 10ppm, like nitrogen and sulphur compound less than 1ppm.

Except methane, in order to help the minimizing of coke, the charging of sending into the dehydrocyclization step can comprise at least a in hydrogen, water, carbon monoxide and the carbonic acid gas.These additives can be used as independent co-fed and introduce, and perhaps may reside in the methane stream, for example are derived under the situation of the Sweet natural gas that contains carbonic acid gas in this methane stream.Other source of carbonic acid gas can comprise stack gas, LNG device, hydrogen production device, ammonia device, glycol units and Tetra hydro Phthalic anhydride device.

In one embodiment, the charging of sending into the dehydrocyclization step contains carbonic acid gas, and comprise about 90-99.9mol%, as about 97-99mol% methane and approximately 0.1-10mol%, like about 1-3mol%CO ₂In another embodiment, the charging of sending into the dehydrocyclization step contains carbon monoxide, and comprise about 80-99.9mol%, as about 94-99mol% methane and approximately 0.1-20mol%, like about 1-6mol%CO.In another embodiment, the charging of sending into the dehydrocyclization step contains steam, and comprise about 90-99.9mol%, as about 97-99mol% methane and approximately 0.1-10mol%, like about 1-5mol% steam.In a further embodiment, the charging of sending into the dehydrocyclization step contains hydrogen, and comprise about 80-99.9mol%, as about 95-99mol% methane and approximately 0.1-20mol%, like about 1-5mol% hydrogen.

The charging of sending into the dehydrocyclization step can also contain than methane high-grade hydrocarbon more, comprises aromatic hydrocarbon.Said more higher hydrocarbon can be discharged step cycle by hydrogen, adds perhaps may reside in the methane stream as independent co-fed, for example when ethane is present in the natural gas feed.The more higher hydrocarbon of discharging step cycle by hydrogen generally include monocyclic aromatic substance and/or mainly have 6 or still less, as 5 or still less, for example 4 or still less, normally 3 or the still less paraffinic hydrocarbons and the alkene of carbon atom.Generally speaking, the charging of sending into the dehydrocyclization step contains less than 5wt%, like the C less than 3wt% ₃+ hydrocarbon. Dehydrocyclization

In the dehydrocyclization step of the inventive method, making the charging that contains methane and dehydrocyclization catalyst is to contact under the condition of more higher hydrocarbon (comprising benzene and naphthalene) effectively making methane conversion, normally non-oxide condition of this condition and reductive condition preferably.The main clean reaction that is comprised; (net reaction) as follows:

; (reaction 1)

; (reaction 2)

; (reaction 3)

The carbon monoxide and/or the carbonic acid gas that possibly be present in the charging improve catalyst activity and stability through promoting following reaction, as: CO ₂Still the clean reaction of competitiveness influences balance to+coke → 2CO (reaction 4) negatively through allowing as follows, as:

(reaction 5)

The condition that is fit to for the dehydrocyclization step comprises about 400 ℃-about 1200 ℃; As about 500 ℃-about 975 ℃; For example about 600 ℃-about 950 ℃ temperature; About about 1000kPa of 1kPa-, like the about 500kPa of about 10-, the for example pressure of about about 200kPa of 50kPa-and the approximately about 1000hr of 0.01- ^-1, like the about 500hr of about 0.1- ^-1, for example about about 20hr of 1- ^-1Weight hourly space velocity.Aptly, this dehydrocyclization step is not having O ₂Carry out under existing.

Can be that the dehydrocyclization catalyst of aromatic substance is used for method of the present invention with any methane conversion that effectively makes, yet generally this catalyzer will comprise metal component, particularly transition metal or its compound on inorganic carrier.Aptly, the amount of this metal component is about 0.1%-20% based on the weight of whole catalyzer, like about 1%-10%.Usually, this metal will be present in the form of carbide in this catalyzer.

The metal component that is suitable for catalyzer comprises calcium, magnesium, barium, yttrium, lanthanum, scandium, cerium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, rhenium, iron, ruthenium, cobalt, rhodium, iridium, nickel, palladium, copper, silver, gold, zinc, aluminium, gallium, silicon, germanium, indium, tin, lead, bismuth and transuranium metal.Said metal component can element form or is existed as metallic compound, like oxide compound, carbide, nitride and/or phosphide, and can be used alone or in combination.Also can platinum and osmium be used as one of metal component, yet generally not be preferred.

Inorganic carrier can be unbodied or crystalline, and especially can be oxide compound, carbide or the nitride of boron, aluminium, silicon, phosphorus, titanium, scandium, chromium, vanadium, magnesium, manganese, iron, zinc, gallium, germanium, yttrium, zirconium, niobium, molybdenum, indium, tin, barium, lanthanum, hafnium, cerium, tantalum, tungsten or other transuranium element.In addition, carrier can be a porous material, like microporous crystalline material or mesopore material.Term as used herein " micropore " is meant the hole of diameter less than 2 nanometers, and term " mesopore " is meant that diameter is the hole of 2-50 nanometer.

The microporous crystalline material that is fit to comprises silicate, silico-aluminate, titanosilicate, titanoaluminosilicatmolecular, aluminate or phosphate, metal phosphate, metallic aluminium phosphoric acid salt, aluminosilicophosphate or its mixture.This microporous crystalline material comprises the material with following framework types: MFI (like ZSM-5, TS-1, TS-2 and silicon zeolite (silicalite)), MEL (like ZSM-11), MTW (like ZSM-12), TON (like ZSM-22); MTT (like ZSM-23), FER (like ZSM-35), MFS (like ZSM-57); MWW (like MCM-22, PSH-3, SSZ-25, ERB-1, ITQ-1, ITQ-2, MCM-36, MCM-49 and MCM-56), IWR (like ITQ-24), KFI (like ZK-5); * BEA (like zeolite beta), ITH (like ITQ-13), MOR (like mordenite); FAU (like X zeolite, Y, overstable Y and dealuminzation Y); LTL (like zeolite L), IWW (like ITQ-22), VFI (like VPI-5); AEL (like SAPO-11), AFI (like ALPO-5) and AFO (SAPO-41), and material such as MCM-68, EMM-1, EMM-2, ITQ-23, ITQ-24, ITQ-25, ITQ-26, ETS-2, ETS-10, ETAS-10, ETGS-10, SAPO-17, SAPO-34 and SAPO-35.The mesopore material that is fit to comprises MCM-41, MCM-48, MCM-50, FSM-16 and SBA-15.

The instance of preferred catalyst is included in molybdenum, tungsten, rhenium and their compound and their binding substances on ZSM-5, silicon-dioxide or the aluminum oxide.

Metal component is dispersed on the inorganic carrier, like co-precipitation, initial wetting, evaporation, dipping, spraying drying, sol-gel, IX, chemical vapour deposition, diffusion and physical mixed through known any means in the affiliated field.In addition, can pass through currently known methods modified inorganic carrier, for example decatize, pickling, alkali cleaning and/or with the element or the compound treatment of silicon-containing compound, P contained compound and/or the periodic table of elements the 1st, 2,3 and 13 families.This modification can be used to change surfactivity and the obstruction of carrier or any internal pore structure that carrier is led in promotion.

This dehydrocyclization step is carried out through the raw material that comprises methane is contacted with dehydrocyclization catalyst in one or more fixed beds, moving-bed or fluidized bed reaction zone.Usually, this raw material in this reaction zone or each reaction zone with the moving-bed contacting of dehydrocyclization catalyst, wherein the travel direction of this raw material and this dehydrocyclization catalyst flows upstream.In one embodiment; This reaction zone comprises the sedimentation bed bioreactor; It is meant vertically arranged reactor drum; Wherein pellet type catalyst near the top of this reactor drum or its, get into and in the action of gravity current downflow forming catalyst bed, this charging simultaneously gets into this reactor drum and upwards flows near the bottom of this reactor drum or its passes this catalyst bed.In alternative embodiment; This reaction zone comprises a plurality of fluidized-bed reactors that are connected in series; Wherein pellet type catalyst is fallen the next adjacent reactor drum this series connection along a direction from a reactor drum, lets this charging pass through between this reactor drum neutralization along opposite direction simultaneously.

The dehydrocyclization reaction is absorbed heat; For heat is provided to this reaction; With intermittently, or more preferably, the successive mode is taken out the first part of catalyzer from reaction zone; And be transferred to independent heating zone, wherein heat this first catalyst member through directly contacting with the hot combustion gas that produces through the combustion fuel supplementary source.First catalyst member that will heat then sends back to this reaction zone.

" fuel refreshment source " is meant that this fuel source physically separates with catalyzer, therefore be not, for example, the coke that on catalyzer, produces as the by product of dehydrocyclization reaction.Usually, this fuel refreshment source comprises hydrocarbon, and like methane, the fuel source that is fit to specifically is the Sweet natural gas as the raw material of this method.Aptly, in this heating zone, keep oxygen-lean atmosphere, so that this hydrocarbon fuel that burns produces synthetic gas to heat this first catalyst member, this synthetic gas can be used for producing other hydrocarbon product and/or fuel then.In addition, the oxidation of the metallic carbide that exist in the use of the oxygen-lean atmosphere inhibition dehydrocyclization catalyst, and average vapor partial pressure is minimized, thus reduce the catalyzer hydrothermal aging.

Perhaps, the fuel refreshment source that is fit to is a hydrogen, the part of the hydrogen that especially produces as the by product of aromatization.

Aptly, said first catalyst member directly contacts in this heating zone with this burnt fuel source.Perhaps, with isolating combustion zone, said heating zone in the said fuel source of burning and the combustion gases that will in this combustion zone, produce be fed to this heating zone to heat this first catalyst member.

In the embodiment of a reality; Prolong this heating zone and make this first catalyst member pass through this heating zone to the other end that is positioned at this heating zone or near the outlet it, wherein on a plurality of positions of on the length of this heating zone, separating, apply heat to first catalyst member from an end or near the inlet it that is positioned at this heating zone.By this way, the heat that inputs to this first catalyst member can be along the length distribution of this heating zone, thereby catalyst surface temperature and inner gradient are minimized.

When heating this first catalysing area timesharing through directly contacting in the heating zone with the burnt fuel source, can realize the heating gradually of this catalyzer as follows: the inlet end that will all basically postcombustions offers this heating zone offers said heating zone in the position along said a plurality of separations of the length of heating zone with this oxygen-containing gas then with increasing gradually.Perhaps, can the desired all basically oxygen-containing gass of the said postcombustion of burning be offered the inlet end of this heating zone, and this postcombustion is offered this heating zone with increasing gradually in the position of said a plurality of separations.

When through with independent combustion zone in the hot combustion gas that produces directly contact and heat this first catalysing area timesharing, can realize the heating gradually of this catalyzer through the position that this hot combustion gas is offered said a plurality of separations of length along the heating zone.

In one embodiment, this heating zone is a riser tube, in the reheat step, makes said first catalyst member upwards through this riser tube.In practice, this heating zone can comprise the riser tube of a plurality of parallel connections.Perhaps, said heating zone can comprise the moving-bed of said catalyzer.

Usually, the temperature of this first catalyst member is about 500 ℃-about 900 ℃ when getting into this heating zone, and temperature is about 800 ℃-about 1000 ℃ when leaving this heating zone.This hot combustion gas is usually less than 1300 ℃, preferably less than 1100 ℃, be more preferably less than under 1000 ℃ the temperature, for example about 800 ℃-less than 1000 ℃ temperature under.Usually, this heating zone is at 10-100psia (69-690kPa), and more preferably the pressure of 15-60psia (103-414kPa) is operated down.Usually, the mean residence time of granules of catalyst in this heating zone is 0.1-100 second, more preferably 1-10 second.

Before introducing this reaction zone again; And preferably through after this heating zone, this first catalyst member can experience one or more stripping steps with the coke removing (a) at least in part and possibly on the surface of this catalyzer, produce or heavy hydrocarbon and/or (b) maybe be by adsorbed water of this catalyzer or oxygen.The stripping of removing coke or heavy hydrocarbon is aptly through making this first catalyst member and steam, hydrogen and/or CO ₂Contact is carried out, and remove anhydrate or the stripping of oxygen aptly through making this first catalyst member and methane, CO ₂Or hydrogen contacts and carries out.

In addition, because this reheat step possibly often make the active metal substance that this first catalyst member is comprised, metallic carbide catalyzed oxidation especially is so the catalyzer of this reheat preferably experienced carburization step before introducing this reaction zone again.Aptly, this carburization step is through making this first catalyst member and H ₂And CO, CO ₂, and/or hydrocarbon such as methane, ethane or propane contacts and carries out, and can carry out at the same time or separately with this water/oxygen stripping step.

Same owing to absorb heat, this dehydrocyclization reaction is deposit coke on catalyzer often, therefore in order to keep the activity of this dehydrocyclization catalyst; With intermittently; Or more preferably, the successive mode is taken out the second section of this catalyzer from reaction zone, and be transferred to independent breeding blanket.The gas that is used for this second catalyst member is delivered to this breeding blanket can comprise O ₂, but preferably comprise the O that compares with air still less ₂, like O less than 10wt% ₂, most preferably less than 5% O ₂This delivering gas can comprise CO ₂And/or H ₂With will be, but preferably be substantially free of H from the part gasification of the coke of this second catalyst member ₂O and under low temperature (usually less than 200 ℃) is not so that this catalyst stream can oxidation and is heated to more than the target temperature of this breeding blanket.

In this breeding blanket, thereby this second catalyst member is contacted removing the coke on this catalyzer at least in part and make under the condition of this catalyst regeneration with oxygen-containing gas.This regeneration gas preferably comprises the O that compares with air still less ₂,, be more preferably less than the O of 5wt% as less than 10wt% ₂, and preferably be substantially free of H ₂O.This regeneration gas can also comprise CO ₂With will be from the part gasification of the coke of this second catalyst member.The suitable source of regeneration gas is the poor O that derives from air separation plant ₂, rich N ₂Materials flow and derive from industry or the high CO of natural gas processing ₂Discharge materials flow (reject stream), be added air or O in this discharge materials flow ₂To reach target O ₂Concentration.Usually this regeneration gas circulates between this breeding blanket and treatment zone, wherein employed regeneration gas cooling is gone out excessive moisture with condensation, adds additional oxygen-containing gas (preferred air) to keep target O ₂Concentration also purges a part to keep constant voltage.Usually, this breeding blanket is at 10-100psia (69-690kPa), and more preferably the pressure of 15-60psia (103-414kPa) is operated down.

This breeding blanket can be the reactor drum as fluidized-bed, liquid bed, sedimentation bed, riser reactor or their binding operation.In practice, this breeding blanket can comprise a plurality of reactor drums, like the riser reactor of a plurality of parallel connections.This breeding blanket should be operated under the needed minimum temperature of coke of aequum is removed in design in the residence time, especially the temperature of this temperature when the volatilization of should exceed MOX or this catalyst substrates do not experience quick deterioration.Usually, the temperature in this breeding blanket is less than the temperature of this reaction zone, and the breeding blanket temperature is about 400 ℃-about 700 ℃ usually, as about 550 ℃-about 650 ℃.The residence time of catalyzer in this breeding blanket also should minimize to reduce catalyst aging speed and to make this catalyzer in reactor drum, bring into play the percentage of time maximization of useful function.Usually, the mean residence time of granules of catalyst in this breeding blanket is 0.1-100 minute, more preferably 1-20 minute.

After leaving this breeding blanket; Perhaps, this second catalyst member is sent back to this reaction zone, is desirable but before the regenerated catalyzer being introduced again this reaction zone, make regenerated second catalyst member contact therefrom to remove adsorbed water and/or oxygen at least in part with methane.In addition, before this regenerated catalyzer is introduced this reaction zone again, through making itself and H ₂And CO, CO ₂And/or hydrocarbon such as methane, ethane or propane contact make this regenerated second catalyst member experience carburization step perhaps be desirable.The water of regenerated catalyzer/oxygen stripping and carburizing can be carried out in single step or as separation steps.

Aptly; The weight that in preset time, is transferred to first catalyst member of this heating zone is about 5: 1 to about 100: 1 with the ratio of the weight of second catalyst member that in the identical time, is transferred to this breeding blanket, preferably approximately 10: 1 to about 20: 1.

In the embodiment of a reality; The dehydrocyclization step is carried out in vertically arranged sedimentation bed bioreactor; Wherein raw material gets into this reactor drum near the bottom of this reactor drum or its, at the top of this reactor drum or near first catalyst member that will heat it and regenerated second catalyst member send back to this reactor drum.Aptly, near the bottom of this reactor drum or its, said first and second catalyst members are taken out, reclaim the elute of this technology at the top of this reactor drum or near it.

In alternative embodiment; This dehydrocyclization step is carried out in a plurality of fluidized-bed reactors that are connected in series; Wherein raw material gets into first reactor drum in this series connection, and first catalyst member and regenerated second catalyst member that heat are returned to last reactor drum in this series connection.Aptly, said first and second catalyst members are taken out from this first reactor drum.

The main ingredient of the elute in this dehydrocyclization step is hydrogen, benzene, naphthalene, carbon monoxide, ethene and unreacted methane.Usually, this elute comprises than the charging as many as and lacks 5wt%, like 10wt% at least, and 20wt% at least for example, the preferred aromatic ring of 30wt% at least.

Then through SX for example and then fractionation from this dehydrocyclization elute, reclaim benzene and naphthalene.Yet, as following will the argumentation, can make at least a portion of these aromatic component before or after product reclaims, experience alkylation step to produce the more material of high value, like YLENE. The hydrogen management

Because hydrogen is the main ingredient of this dehydrocyclization elute; Therefore, after the recovery of aromatic products, make elute experience hydrogen discharge step; Thereby unreacted methane cycle to dehydrocyclization step was being reduced the hydrogen richness of elute in the past, and making the maximization of charging utilization ratio.Common said hydrogen is discharged step and is comprised at least a portion hydrogen and oxygen carrier (preferred CO and/or the CO that makes in the dehydrocyclization elute ₂) reaction, to generate the water and the second elute materials flow, it is compared hydrogen richness and reduces with the materials flow of first (dehydrocyclization) elute.The hydrogen discharge method that is fit to is described in the common pending trial PCT application number PCT/US2005/044042 (attorney 2004B154) of following and submission on December 2nd, 2005.

Aptly, hydrogen discharge step can comprise (i) methanation and/or ethaneization, (ii) fischer-tropsch process, (iii) C ₁-C ₃Alcohol, particularly methyl alcohol and other oxygenatedchemicals synthetic, (iv) light olefin, paraffinic hydrocarbons and/or aromatic substance is synthetic, via methyl alcohol or dme midbody, and/or (v) selective hydrogen burning.Can adopt these steps to obtain maximum interests in order; For example can at first take fischer-tropsch process to obtain to be rich in C ₂+ materials flow, then carry out methanation to reach high H ₂Transformation efficiency.

Usually, be described below, said hydrogen is discharged step will produce hydrocarbon, and in this case, after isolating the water of common generation, at least a portion with said hydrocarbon is circulated to the dehydrocyclization step aptly.For example; When the hydrocarbon that produces in the hydrogen discharge step comprises paraffinic hydrocarbons and alkene; The said part that is circulated to the dehydrocyclization step comprises 6 or carbon atom still less aptly; For example 5 or carbon atom still less, the for example paraffinic hydrocarbons or the alkene of 4 or carbon atom still less or 3 or carbon atom still less.Wherein, hydrogen is discharged the hydrocarbon that produces in the step and is comprised aromatic substance, and the said part that is circulated to the dehydrocyclization step comprises the monocyclic aromatic material aptly. Methanation/ethaneization

In one embodiment; Hydrogen is discharged step and is comprised at least a portion hydrogen and the reaction of carbonic acid gas in the dehydrocyclization elute, to produce methane and/or ethane according to following clean reaction:

(reaction 6)

(reacting 7).

Used carbonic acid gas is the part of natural gas stream aptly, preferably as the part of the identical natural gas stream of the charging of said dehydrocyclization step.At this carbonic acid gas is to contain under the situation of a part of methane stream the CO of said materials flow ₂: CH ₄Remain on about 1 aptly: 1-0.1: 1.Mixing aptly through gaseous feed being provided to the inlet of injector of carbonated materials flow and dehydrocyclization elute realizes.

The hydrogen that produces methane or ethane is discharged step and is taked with the reaction of expecting 6 usually or react 7 required approaching H of stoichiometric ratio ₂: CO ₂Mol ratio is if but the expectation generation contains CO ₂Or contain H ₂The second elute materials flow, can on stoichiometric ratio, make little change.The hydrogen discharge step that produces methane or ethane is carried out in the presence of dual-function catalyst aptly, and this catalyzer contains metal component (particularly transition metal) or its compound on inorganic carrier.The metal component that is fit to comprises copper, iron, vanadium, chromium, zinc, gallium, nickel, cobalt, molybdenum, ruthenium, rhodium, palladium, silver, rhenium, tungsten, iridium, platinum, gold, gallium and their binding substances and compound.Inorganic carrier can be an amorphous material, like silicon-dioxide, aluminum oxide or silica-alumina, perhaps as for cited those of catalyst for dehydroaromatizationof.In addition, inorganic carrier can be a crystalline material, like micropore or mesopore crystalline material.The porous crystalline material that is fit to comprises above silico-aluminate, aluminate or phosphate and the aluminosilicophosphate of enumerating for dehydrocyclization catalyst.

The hydrogen discharge step that produces methane and/or ethane can be carried out under the condition of wide region; Comprise about 100 ℃-about 900 ℃, like about 150 ℃-about 500 ℃, about 200 ℃-about 400 ℃ temperature for example; About 200kPa-about 20; 000kPa, like the pressure of the about 5000kPa of about 500-, and approximately 0.1-is about 10,000hr ^-1, about 1 like about 1-, 000hr ^-1Weight hourly space velocity.CO ₂Level of conversion is generally 20-100%, is preferably greater than 90%, as greater than 99%.This thermopositive reaction can be carried out in a plurality of catalyst beds, between bed, removes heat.In addition, preposition bed (lead bed) (one or more) is operated so that kinetic rate maximizes under comparatively high temps, and the bed (tail bed) (one or more) of afterbody is operated so that the maximization of thermodynamic change rate at a lower temperature.

The primary product of this reaction is a water, and depends on H ₂: CO ₂Mol ratio is methane, ethane and higher alkane more, together with some undersaturated C ₂Higher hydrocarbon more.In addition, the some parts hydrogenation of preferably carbon dioxide to carbon monoxide.Remove anhydrate after, can make methane, carbon monoxide, any unreacted carbonic acid gas and more higher hydrocarbon be fed directly to the dehydrocyclization step to produce extra aromatic products. Fischer-tropsch process

In another embodiment, said hydrogen is discharged step and is comprised at least a portion hydrogen and the reaction of carbon monoxide according to fischer-tropsch process in the dehydrocyclization elute, with generation C ₂-C ₅Paraffinic hydrocarbons and alkene.

Fischer-tropsch process is known in the affiliated field, for example referring to the United States Patent(USP) Nos. of incorporating this paper by reference into 5,348,982 and 5,545,674.This technology generally includes the reaction of hydrogen and carbon monoxide, and its mol ratio is about 0.5: about 4: 1 of 1-, about 2.5: 1 of preferably approximately 1.5: 1-, and temperature of reaction is 180 ℃-about 240 ℃ of about 175 ℃-about 400 ℃, preferably approximately; Pressure is the about 100bar (100-10 of about 1-; 000kPa), the about 40bar of preferably approximately 10-(1,000-4,000kPa); Be reflected under the Fischer-Tropsch catalyst existence and carry out; This catalyzer generally is the group VIII base metal that supports or do not support, and like Fe, Ni, Ru, Co, it has or do not have promotor such as ruthenium, rhenium, hafnium, zirconium, titanium.When adopting carrier its can be the high-melting point metal oxide compound like the IVB family metal oxide, i.e. titanium oxide, zirconium white or silicon-dioxide, aluminum oxide or silica-alumina.In one embodiment, catalyzer comprises non-transformation catalyst, and like cobalt or ruthenium, preferred cobalt as promotor, preferably is supported on cobalt and rhenium on silicon-dioxide or the titanium oxide (preferred titanium oxide) with rhenium or zirconium.

In another embodiment, hydrocarbon synthesis catalyst is included in metal such as Cu, Cu/Zn or the Cr/Zn on the ZSM-5, moves this method to produce the monocyclic aromatic hydrocarbon of significant quantity.The instance of above-mentioned technology is at the Study of Jose Erena of Physical Mixtures ofCr ₂O ₃-ZnO and ZSM-5 Catalysts for the Transformation of Syngasinto Liquid Hydrocarbons; Ind.Eng.Chem Res.1998,37, obtain among the 1211-1219 describing, it incorporates this paper by reference into.

Reclaim fischer-tropsch liquid, i.e. C ₅+, and make light gas such as unreacted hydrogen and CO, C ₁To C ₃Or C ₄And water separates with heavy hydrocarbon more.Then can with this more heavy hydrocarbon reclaim or be fed in the dehydrocyclization step as product to produce extra aromatic products.

The required carbon monoxide of Fischer-Tropsch reaction can be fully or partly by be present in contain in the methane feed or provide with the carbon monoxide of its co-fed and the carbon monoxide that in the dehydrocyclization step, generates as by product.The words that need; Extra carbon monoxide can produce as follows: through for example making contained feed carbon dioxide to transformation catalyst (shifting catalyst) in the Sweet natural gas, thus via the reverse water gas shift reaction:

(reaction 8) and via following reaction:

generates carbon monoxide. Alcohol is synthetic

In another embodiment, said hydrogen is discharged step and is comprised at least a portion hydrogen and the reaction of carbon monoxide in the dehydrocyclization elute, with generation C ₁-C ₃Alcohol, particularly methyl alcohol.Producing methyl alcohol from synthetic gas also is known with other oxygenatedchemicals, for example in United States Patent(USP) Nos. 6,114,279; 6,054,497; 5,767,039; 5,045,520; 5,254,520; 5,610,202; 4,666,945; 4,455,394; 4,565,803; Obtain in 5,385,949 describing, this paper is incorporated in their explanation by reference into.Usually, the hydrogen (H that has of used synthetic gas ₂) and oxycarbide (CO+CO ₂) mol ratio be about 0.5: 1-20: 1, be preferably greater than 2: 1-10: 1, carbonic acid gas randomly exists with the amount that is not more than 50wt% based on the gross weight of this synthetic gas.

The catalyzer that is used for methanol synthesizing process generally comprises the oxide compound that is selected from least a element in copper, silver, zinc, boron, magnesium, aluminium, vanadium, chromium, manganese, gallium, palladium, osmium and the zirconium.Aptly, this catalyzer is based on the catalyzer of copper, like the form with cupric oxide, randomly in the presence of the oxide compound of at least a element in being selected from silver, zinc, boron, magnesium, aluminium, vanadium, chromium, manganese, gallium, palladium, osmium and zirconium.Aptly, this catalyzer oxide compound of containing cupric oxide and being selected from least a element in zinc, magnesium, aluminium, chromium and the zirconium.In one embodiment, methanol synthesis catalyst is selected from cupric oxide, zinc oxide and aluminum oxide.More preferably, the oxide compound of this catalyzer cupric and zinc.

Said methanol synthesizing process can carry out in wide temperature and pressure scope.The temperature that is fit to is about 150 ℃-about 450 ℃, as about 175 ℃-about 350 ℃, and for example about 200 ℃-about 300 ℃.The pressure that is fit to is about 1, and 500kPa-is about 12,500kPa, and as about 2,000kPa-is about 10, and 000kPa is for example about 2, and 500kPa-is about 7,500kPa.Gas hourly space velocity depends on used technology type and changes, yet usually the gas hourly space velocity of the gas flow through catalyst bed is about 50hr ^-1-about 50,000hr ^-1, like about 250hr ^-1-about 25,000hr ^-1, more preferably about 500hr ^-1-about 10,000hr ^-1This thermopositive reaction can be carried out in fixed bed or fluidized-bed, is included in a plurality of catalyst beds that remove heat between bed.In addition, preposition bed (one or more) is operated so that kinetic rate maximizes under comparatively high temps, and the bed (one or more) of afterbody is operated so that the thermodynamic change maximization at a lower temperature.

Gained methyl alcohol and/or other oxygenatedchemicals can be used as independent product and sell; Can be used for the aromatic alkylation that the dehydrocyclization step generates is become the more product such as the YLENE of high value; Perhaps can be as the raw material of producing light alkene, particularly ethene and propylene.Methyl alcohol to conversion of olefines is known technology, for example at United States Patent(USP) No. 4,499, obtains in 327 describing, and it incorporates this paper by reference into. Selective hydrogen burning

In another embodiment; Said hydrogen is discharged step and is comprised selective hydrogen burning; This is following technology: hydrogen and oxygen in the mixture flow are reacted with formation water or steam, and the hydrocarbon in this materials flow does not form the hydrocarbon of carbon monoxide, carbonic acid gas and/or oxidation basically with the oxygen reaction.Generally speaking, selective hydrogen burning contain oxygen solid material such as mixed metal oxide in the presence of carry out, this material can be emitted a part of bonded oxygen to hydrogen release.

A kind of suitable selective hydrogen burning technology is at the United States Patent(USP) No. of incorporating this paper by reference into 5; 430; Obtain in 210 describing; Be included in second materials flow that makes first materials flow that contains hydrocarbon and hydrogen under the reactive conditions and contain aerobic and contact with the separation surfaces of the impervious film of non-oxygen-containing gas, wherein said film comprises hydrogen burning MOX selectively, and the product that reclaims selective hydrogen burning.Said MOX is the mixed metal oxide of bismuth, indium, antimony, thallium and/or zinc normally.

Incorporate the United States Patent(USP) No. 5,527,979 of this paper by reference into and described a kind of clean catalytic oxidative dehydrogenation of alkane that is used for to produce the method for alkene.This method comprises the simultaneous balance dehydrogenation of alkanes to alkenes and makes this balance dehydrogenation reaction further tend to the selective combustion of the hydrogen that forms of product alkene.Especially; In first reactor drum, make the alkane charging on the balance dehydrogenation catalyst, carry out dehydrogenation; Elute from this first reactor drum is got in second reactor drum that contains metal oxide catalyst with oxygen, and this catalyzer is used for the burning of selectivity catalysis hydrogen.This balance dehydrogenation catalyst can comprise platinum, and this selective metal oxide compound combustioncatalysts can bismuth-containing, antimony, indium, zinc, thallium, lead and tellurium or their mixture.

On August 5th, 2004, U.S. Patent Application Publication 2004/0152586 open and that incorporate this paper by reference into was described a kind of method that is used to reduce from the hydrogen richness of the elute of cracking case.This method adopts and comprises following catalyst system: (1) at least a solid acid cracking component and (2) at least a selective hydrogen burning component based on metal; It is formed by (a) with (b) basically, and wherein (a) is selected from following metal junctions compound: i) from least a metal of the periodic table of elements the 3rd family with from least a metal of 4-15 family; Ii) from least a metal of periodic table of elements 5-15 family with from one of at least at least a metal in the periodic table of elements the 1st, 2 and 4 families; Iii) from least a metal of periodic table of elements 1-2 family, from least a metal of the 3rd family with from least a metal of 4-15 family; And iv) from two kinds or more kinds of metal of periodic table of elements 4-15 family; (b) at least a in oxygen and the sulphur, wherein at least a not only Chemical bond in oxygen and the sulphur within the said metal but also Chemical bond between said metal.

Selective hydrogen burning reaction of the present invention is generally carried out under about 300 ℃-about 850 ℃ temperature and the pressure of about about 20atm of 1atm-(100-2000kPa). Aromatic products recovery/processing

The primary product of dehydrocyclization step is benzene and naphthalene.Can be usually with subsequently fractionation these products be separated from the dehydrocyclization elute, then as the direct marketing of commercial chemistry material through SX.Perhaps; Can with some or all benzene and/or decalin base to produce; For example, toluene, YLENE and alkylnaphthalene, and/or can let its experience hydrogenation to produce; For example, hexanaphthene, tetrahydrobenzene, dialin (benzyl rings hexene), tetraline (tetralin), hexahydro-naphthalene (bicyclo hexene), octalin and/or naphthane (naphthalane).The alkylation that is fit to and method for hydrogenation are described and at the common pending trial PCT application number PCT/US2005/043523 that we submitted on December 2nd, 2005, have been carried out more detailed description among the PCT/US2005/044038 (attorney 2004B155) of (attorney 2004B156) and on December 2nd, 2005 submission following. Aromatic alkylation

The aromatic substance for example alkylation of benzene and naphthalene is known in the art, and is usually included under the existence of acid catalyst the reaction of alkene, alcohol or alkylogen and aromatic substances in gas phase or liquid phase.The acid catalyst that is fit to comprises mesopore zeolite (be that restricted index is those of 2-12, like United States Patent(USP) No. 4,016, limited in 218); It comprises the material with following framework types: MFI (like ZSM-5 and silicon zeolite), MEL (like ZSM-11), MTW (like ZSM-12), TON (like ZSM-22); MTT (like ZSM-23), MFS (like ZSM-57) and FER (like ZSM-35) and ZSM-48, and large pore zeolite (be restricted index less than 2 those); As the material with following framework types: BEA (like zeolite beta), and FAU (like ZSM-3, ZSM-20; X zeolite, Y, overstable Y and dealuminzation Y); MOR (like mordenite), MAZ (like ZSM-4), MEI (like ZSM-18) and MWW (like MCM-22, PSH-3, SSZ-25, ERB-1, ITQ-1, ITQ-2, MCM-36, MCM-49 and MCM-56).

In an embodiment of the inventive method, from the dehydrocyclization elute, reclaim benzene, use alkene (for example discharging the ethene of the by product generation of step) with its alkylation then as the hydrogen that uses ethaneization/methanation.The usual conditions that are used to carry out the vapor-phase alkylation of benzene and ethene comprise the temperature of about 900 ℉ of about 650-(343-482 ℃), and approximately normal atmosphere is to about 3000psig (100-20, pressure 800kPa), the approximately about 2.0hr of 0.5- ^-1The WHSV and 1 based on ethene: 1-30: 1 the benzene and the mol ratio of ethene.The liquid-phase alkylation of benzene and ethene can be in the temperature of 300-650 ℉ (150-340 ℃), and high extremely about 3000psig (20, pressure 800kPa), the approximately about 20hr of 0.1- ^-1The WHSV and 1 based on ethene: 1-30: carry out under 1 the benzene and the mol ratio of ethene.

Preferably; Under liquid-phase condition at least partly; With containing at least a catalyzer among zeolite beta, zeolite Y, MCM-22, PSH-3, SSZ-25, ERB-1, ITQ-1, ITQ-2, ITQ-13, ZSM-5, MCM-36, MCM-49 and the MCM-56, carry out the ethylization of benzene.

The ethylization of benzene is carried out in the place of dehydrocyclization/hydrogen discharge process, perhaps can benzene be transported to another position to be converted into ethylbenzene.The ethylbenzene that obtains then can be sold, perhaps be isomerizated into xylol through the method for affiliated known as for example producing cinnamic precursor.

In another embodiment of the inventive method, alkylating agent is methyl alcohol or dme (DME) and is used to make benzene and/or the decalin base of recovery from dehydrogenation cyclisation elute, to produce toluene, YLENE, methylnaphthalene and/or dimethylnaphthalene.Methyl alcohol or DME are being used under the situation of alkylated benzenes; Carry out comprising in the presence of the catalyzer of zeolite aptly; Said zeolite such as ZSM-5, zeolite beta, ITQ-13, MCM-22, MCM-49, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35 and ZSM-48, this zeolite be through the decatize modification so that at 2 of 120 ℃ temperature and 60torr (8kPa), and 2-dimethylbutane pressure is down during measurement; To 2, the 2-dimethylbutane has about 0.1-15 second ^-1Diffusion parameter.Aforesaid method is selective for the production of p-Xylol, and is for example obtaining describing in the United States Patent(USP) No. 6,504,272, and it incorporates this paper by reference into.When methyl alcohol is used for alkylated naphthalene, in the presence of the catalyzer that comprises ZSM-5, MCM-22, PSH-3, SSZ-25, ERB-1, ITQ-1, ITQ-2, ITQ-13, MCM-36, MCM-49 or MCM-56, carry out aptly.Aforesaid method can be used for selectivity and produce 2, the 6-dimethylnaphthalene, and it is for example obtaining describing in the United States Patent(USP) Nos. 4,795,847 and 5,001,295, and it incorporates this paper by reference into.

Under methyl alcohol or DME situation as the alkylating agent in the inventive method, its can be used as independent charging offer this method or can be at least in part through add carbonated feed gas (for example natural gas stream) to the part or all of elute Central Plains that derives from the dehydrocyclization step generation.Especially; Before any separation of aromatic component, can the dehydrocyclization elute be fed to transformation by reciprocal direction reactor drum (reverse shift reactor) and under the condition of the carbon monoxide content that improves these elutes through above-mentioned reaction 5 for example and 8, react with carbonated charging.

In addition, can be with methane and CO ₂And/or steam feed to transformation by reciprocal direction reactor drum can mix this synthetic gas with the needs according to alkylation step then and regulate H to produce synthetic gas with the part of dehydrocyclization elute ₂/ CO/CO ₂Ratio.

Usually, the transformation by reciprocal direction reactor drum is included in the catalyzer that contains transition metal on the carrier, like the Fe on aluminum oxide, silicon-dioxide or titanium oxide, Ni, Cr, Zn; And under following condition, move: comprise about 500 ℃-about 1200 ℃, like about 600 ℃-about 1000 ℃, about 700 ℃-about 950 ℃ temperature for example; Approximately 1kPa-is about 10,000kPa, as about 2, and 000kPa-about 10; 000kPa, for example approximately 3000kPa-is about 5, the pressure of 000kPa.Gas hourly space velocity can depend on the type change of method therefor, yet usually the gas hourly space velocity of the gas flow through catalyst bed is about 50hr ^-1-about 50,000hr ^-1, like about 250hr ^-1-about 25,000hr ^-1, more preferably about 500hr ^-1-about 10,000hr ^-1

Elute from the transformation by reciprocal direction reactor drum is fed in the alkylation reactor, and this reactor drum moves under the feasible condition that takes place such as the reaction of following grade:

(reaction 9) CH ₃OH+C ₆H ₆→ toluene+2H ₂O (reaction 10) 2CH ₃OH+C ₆H ₆→ YLENE+2H ₂O (reaction 11)

The suitable condition that is used for this alkylation reactor will comprise the temperature that about 100-is about 700 ℃, approximately about 300 normal atmosphere of 1-(100-30, pressure 000kPa) and about about 100hr of 0.01- ^-1Aromatic hydrocarbon WHSV.The catalyzer that is fit to will comprise that restricted index is the molecular sieve of 1-12, ZSM-5 for example, and it is usually together with the oxide compound of one or more metals or MOX such as copper, chromium and/or zinc.

Preferably, comprise at alkylation catalyst under the situation of molecular sieve, should be molecular sieve modified changing its diffusion property, so that are p-Xylol through reacting the 11 main xylene isomers that produce.The appropriate method of diffusional modification comprises that decatize and silicon compound, coke, MOX (like MgO) and/or P are on the molecular sieve surface or strange land in the opening of hole or sedentary deposit.Further preferably reactive metal is introduced this molecular sieve so that more the material of hyperergy such as alkene are saturated, this more the hyperergy material can be used as by product and produce and otherwise possibly cause catalyst deactivation.

Can the elute that derive from alkylation reactor be fed to the disengaging zone then, in this disengaging zone, will at first aromatic products be separated with other low molecular weight material with hydrogen through SX aptly.Can be benzene cut, toluene fraction, C with the compound product fractionation then ₈Cut and contain naphthalene and the heavy ends of alkylated naphthalene.Then can be with this C ₈Aromatic fraction is fed to crystallization or sorption process to separate valuable p-Xylol component and remaining xylol, and it is sold as product or is fed to isomerization loop to produce more p-Xylol.Can this toluene fraction be taken out as the product that adapts to, or be circulated to alkylation reactor, or be fed to the toluene disproportionation device, preferably be used for the selectivity toluene disproportionation device of the outer p-Xylol of delivery capacity. Aromatic substance hydrogenation

Except alkylation step or replace alkylation step, can make at least a portion aromatic component hydrogenation in the dehydrocyclization elute to produce useful product such as hexanaphthene, tetrahydrobenzene, dialin (benzyl rings hexene), tetraline (tetralin), hexahydro-naphthalene (bicyclo hexene), octalin and/or naphthane (naphthalane).These products can be used as fuel and chemical intermediate, can be as the solvent of extraction aromatic component from the dehydrocyclization elute under the situation of tetralin and naphthalane.

But said hydrogenation is optionally carried out after isolation of aromatic component from the dehydrocyclization elute aptly, and adopts the part hydrogen that is produced by the dehydrocyclization reaction aptly.The aromatic substance hydrogenation process that is fit to is affiliated known, adopts the catalyzer that comprises the Ni, Pd, Pt, Ni/Mo or the sulfurized Ni/Mo that are supported on aluminum oxide or the silica supports usually.The operational condition that is suitable for this hydrogenation process comprises about 300-about 1; 000 ℉ (150-540 ℃), like the temperature of about 700 ℉ of about 500-(260-370 ℃); Approximately 50-is about 2,000psig (445-13890kPa), like the pressure of the about 500psig of about 100-(790-3550kPa) and the about about 50hr of 0.5- ^-1, like the about 10hr of about 2- ^-1WHSV.

The partially hydrogenated that in product, stays one or more olefinic C-Cs also possibly be desirable, so that produce the material that is suitable for polymerization or the conversion of other downstream chemical.The partially hydrogenated technology that is fit to is affiliated known, and uses to comprise usually and be supported on MOX such as La ₂O ₃The catalyzer of the precious metal (preferred ruthenium) that-ZnO is last.Also can use homogeneous phase noble metal catalyst system.The instance of partially hydrogenated technology is in United States Patent(USP) Nos. 4,678,861; 4,734,536; 5,457,251; 5,656,761; 5,969,202; With 5,973, disclose in 218, their full content is hereby incorporated by.

Alternative hydrogenation process comprises the low pressure hydrocracking of naphthalene component on catalyzer to produce korenyl, and said catalyzer is such as the sulfurized Ni/W or the sulfurized Ni that are supported on amorphous aluminosilicate or zeolite such as X zeolite, zeolite Y or the zeolite beta.Be suitable for low pressure hydrogenation cracked operational condition and comprise about 300-about 1; 000 ℉ (150-540 ℃), like the temperature of about 700 ℉ of about 500-(260-370 ℃); Approximately 50-is about 2,000psig (445-13890kPa), like the pressure of the about 500psig of about 100-(790-3550kPa) and the about about 50hr of 0.5- ^-1, like the about 10hr of about 2- ^-1WHSV.

Referring now to accompanying drawing and embodiment multiple non-limiting embodiments of the present invention is described more specifically.

Fig. 1 shows dehydrocyclization reactor drum and the simplified design of catalyzer reheater according to the first embodiment of the present invention.In this embodiment; This dehydrocyclization reactor drum comprises vertically arranged sedimentation bed bioreactor 11; The catalyzer of heating flows to this reactor drum 11 through near the inlet the top that is positioned at this reactor drum 11 12, and the refrigerative catalyzer flows out from this reactor drum 11 via near the outlet that valve is housed 13 the bottom that is arranged in this reactor drum 11.Usually, the catalyzer of this heating gets into this reactor drum 11 under about 900 ℃ temperature, and this refrigerative catalyzer leaves this reactor drum under about 650 ℃ temperature.

Methane feed 14 is introduced this reactor drum 11 near the bottom of this reactor drum, and use extra methane or methane add air 15 as postcombustion with this refrigerative catalyst transport to catalyzer reheater 16.Usually, when purpose was the co-production synthetic gas, the amount that is used as the methane of this postcombustion was the about 120wt% as the amount of the methane of the charging 14 that gets into this dehydrocyclization technology.Usually, when purpose was not the co-production synthetic gas, the amount that is used as the methane of this postcombustion was the about 65wt% as the amount of the methane of the charging 14 that gets into this dehydrocyclization technology.

The form of this catalyzer reheater 16 is vertically arranged riser tubes, and wherein this refrigerative catalyzer is upwards carried through this riser tube by this methane fuel, and oxygen injects this riser tube through a plurality of inlets 17 of separating along the length of this riser tube.Thereby the oxygen that injects this reheater 16 makes this methane fuel burning and when catalyzer flows through this riser tube, improves the temperature of this catalyzer.The amount of the oxygen that control is introduced through each inlet 17 is so that keep the oxygen-lean atmosphere in this riser tube, thereby the burning of this postcombustion and the therefore heating of this catalyzer are carried out through this riser tube along with this catalyzer upwards flows gradually.This makes the exposure of this catalyzer under excessive temperature minimize, and causes the incomplete oxidation of this fuel so that the elute that burns to be rich in carbon monoxide.This burning elute leaves reactor drum 16 through exporting 18, and comprises 59wt%H usually ₂, 30wt%CO, 8wt%H ₂O and 3wt%CO ₂Therefore, this burning elute comprises the source of suitable synthetic gas, and this synthetic gas can be used for producing other hydrocarbon product and/or fuel.

Near the top of riser tube 16 or its; The catalyzer of this heating gets into catalyst vapor stripper 19; Wherein make this catalyzer contact with other methane with remove maybe be by the water or the oxygen of this catalyzer absorption, return to reactor drum 11 through 12 catalyzer that will heat that enter the mouth then.Take out from this reactor drum 11 via reactor drum 11 tops or near the outlet (not shown) it elute (comprising aromatic hydrocarbon) this technology.

Second embodiment of the present invention is shown in Fig. 2, and wherein the dehydrocyclization reactor drum is provided with catalyzer reheater and independent catalyst regenerator.The same with first embodiment; This dehydrocyclization reactor drum comprises vertically arranged sedimentation bed bioreactor 21; The catalyzer of heating flows to this reactor drum 21 through near the inlet the top that is positioned at this reactor drum 21 22, and the refrigerative catalyzer flows out from this reactor drum 21 via near the outlet of first and second the bottom that lays respectively at this reactor drum 21 23,24.Methane feed 25 is introduced this reactor drum 21 near the bottom of reactor drum 21.

From the bottom that this first outlet 23 flows to riser tube reheater 26, wherein this catalyst entrainment is in the mixture of air that gets into these riser tubes through manifold 27 and methane fuel under action of gravity in the first part of this refrigerative catalyzer.This catalyzer is upwards carried in riser tube 26 and through combustion of methane it is heated in through riser tube 26 processes through this air/methane mixture at it.The mixture that gets into riser tubes 26 through manifold 27 comprises this catalyzer is heated to desired all fuel of desired reaction temperature, but oxygen is insufficient.Therefore; Through a plurality of inlets 28 of separating along the length of this riser tube (for simplicity; Two inlets 28 only are shown among Fig. 2; But in fact this number maybe be much bigger) in riser tube 26, introduce other air, thus the heating of this catalyzer is carried out through riser tube 26 along with this catalyzer upwards flows gradually.

Behind the top of leaving riser tube 26, the catalyzer of this heating gets into separator 29, wherein this solid granular catalyst is separated with combustion gases, makes it to get into activator/stripping tower 32 then.Then these combustion gases are supplied with cyclonic separator 31 so that remove catalyst fines, carry out recovery of heat then.In this reheater, use air as combustion medium, these combustion gases comprise 67.9wt%N usually ₂, 0.2wt%O ₂, 1.3wt%H ₂, 3.6wt%CO, 7.9wt%CO ₂And 17.3wt%H ₂O.

From the bottom that second outlet 24 flows to riser regenerator 33, wherein upwards carry in the oxygen-containing gas materials flow and along this riser regenerator by this catalyst entrainment under action of gravity for the second section of this refrigerative catalyzer.When this second catalyst member when the revivifier 33, will be in dehydrocyclization reactor drum 21 at the coke that produces on this catalyzer burning-off from this catalyzer, thereby heat this catalyzer.Yet, preferably control revivifier 33, so that the temperature of second catalyst member of leaving this revivifier is less than the temperature of second catalyst member that leaves this reactor drum 21 through the temperature that for example reduces the oxygen-containing gas be fed to revivifier 33.Usually, the temperature of leaving second catalyst member of revivifier 33 is about 550 ℃, and when leaving reactor drum 21 this second catalyst member under about 650 ℃ temperature.

After leaving the top of revivifier 33, this second catalyst member gets into separator 34, and this solid granular catalyst separates with combustion gases in this separator, then these combustion gases is fed to cyclonic separator 31 so that remove catalyst fines.This isolating granules of catalyst flows to activator/stripping tower 32 then.

In this activator/stripping tower 32, this regenerated catalyzer at first makes progress mobile hydrocarbon flow 35 like methane, ethane or propane and H with bottom from this container ₂And/or CO contact, so that the metal recarburization on this catalyzer, because this regeneration step not only removes surface char from this catalyzer, also often with the activated carbide material catalyzed oxidation on the metal component of this catalyzer.This catalyzer is contacted with methane stream 36 maybe be by the water or the oxygen of this catalyzer absorption to remove.Then this regenerated catalyzer is combined with catalyzer from the reheat of riser tube 26, and make this bonded catalyzer and hydrogen and/or CO ₂Coke or the heavy hydrocarbon of materials flow 37 contacts to remove any remnants.After this catalyst stripping, this hot gas upwards flows to help the regenerated catalyst member in this recarburization section of heating.22 this bonded catalyzer returned to reactor drum 21 through entering the mouth then.Preferably all gas streams that are fed to this container are preheated so that temperature loss minimizes.Though this accompanying drawing has shown all effects in single container, it should be understood that this activity can be carried out for the ease of structure or operation in a plurality of containers.

The 3rd embodiment of the present invention is shown in Fig. 3; Wherein the dehydrocyclization reactor drum comprises the fluidized-bed reactor 41 that a plurality of (being 3 in this case) are vertically separated, are connected in series, in this fluidized-bed reactor from the thermocatalyst of the stripping tower 42 of catalyzer reheater (not shown) get into uppermost reactor drum 41 and with through enter the mouth 43 introduce nethermost reactor drum 41 the methane contrary move down to ground.The refrigerative catalyzer is taken out and delivers to this catalyzer reheater from this nethermost reactor drum 41.Those shown in common and Fig. 2 are identical with revivifier for the reheater that uses together with the design of the fluidized-bed of Fig. 3.The granularity (being typically about about 10, the 000 μ m of 1,000 μ m-) of the catalyzer that the granularity that it should be understood, however, that the catalyzer that uses in the fluidized-bed design of Fig. 3 is used in the sedimentation bed than Fig. 1 and 2 usually is littler, for example is the about 500 μ m of about 50 μ m-.

Fig. 4 shows a kind of suitable device, and it is used for controlling the flow of riser tube of the catalyst regenerator of this catalyzer catalyzer reheater and/or Fig. 2 through being used for Fig. 1 and 2.This device comprises catalyzer receiving tank 51, and it holds the cooling of receiving from this dehydrocyclization reactor drum (not shown) via pipeline 52/used the bed of catalyzer.To be the oxygen-denuded air form and be used to regenerate or be the lift gas that the fuel/air mixture form is used for the catalyzer reheat and offer groove 51, and be divided into main air-flow and secondary airflow through valve 54,55 via pipeline 53.This main air communication piping 56 is fed to the zone of the groove 51 under the lower end that is positioned at riser tube 57, any significant thickness through this catalyst bed so that main lift gas upwards flows through this riser tube 57.

This less important lift gas is fed to the zone of separating the groove 51 of remarkable distance with the lower end of riser tube 57 through pipeline 58, and the remarkable thickness of this catalyst bed is to arrive this riser tube so that this less important lift gas must be flowed through.This less important lift gas advances the materials flow of main lift gas with this granules of catalyst, and wherein this granules of catalyst is carried secretly and upwards promoted along riser tube 57.To change this relative discharge main and less important lift gas, can change flow and so this catalyzer the flow this riser tube 57 in of this granules of catalyst through by-pass valve control 54,55 through this riser tube 57.Usually, the flow of this less important lift gas changes between the 5-15% of this total air flow.

In the embodiment shown in this figure, the riser tube that is used for this catalyzer reheater and this catalyst regenerator has along the cardinal principle constant inner diameter of the length of this riser tube.Yet under some situation, the top increase of internal diameter from the bottom to this riser tube that this riser tube is set possibly be desirable.

Though do not illustrate among this figure; But expectation is used from " used heat " of this other part of technology so that this methane (as to be transformed as the charging of aromatic substance with as the fuel that is used for this catalyzer reheater) is preheated; Being preferably up to about 600 ℃ and the oxygen charging that contains that will get into this catalyzer reheater preheats to the highest obtainable temperature.Embodiment 1: the room and time dependency that catalyst temperature distributes in the reheater

Inside (space) temperature distribution of calculating the catalyst particles intragranular under following two kinds of situation with its along this riser tube axially upwards with the dependency of time: (A) when adding the desired air of all methane oxidations in the riser tube bottom (; The catalyzer residence time in riser tube is when being zero) and (B) when this air feed during along this riser tube axial distribution (like in fact possible discontinuous catalyzer time period of stay under perhaps " continuously " the air decanting point under the infinitesimal timed interval (or riser tube length) with performance modeling theory, best).Be used to calculate the temperature distribution T (r of the inner time correlation of granules of catalyst (being assumed to spheroid); T) method comprises that numerical solution is used for the heat transfer equation formula of the simplification of unstable state, one dimensional heat transfer, the homogeneous reaction that does not combine with convection current and radiative transfer final condition at particle surface: $\frac{\∂T}{\∂t}=D(\frac{{\∂}^{2}T}{{\∂r}^2}+\frac{2}{r}\frac{\∂T}{\∂r})$ $-k\frac{\∂T}{\∂r}=h(T_{\mathrm{Surface}}-T_{\mathrm{Flue}})+\mathrm{\σ\; \ϵ}(T_{\mathrm{Surface}}^4-T_{\mathrm{Flue}}^4)$ Wherein r is the radial distance from this ball centre, and t is the catalyzer residence time in riser tube, and D is a thermal diffusivity, and k is the catalyzer thermal conductivity, and h is a convective heat-transfer coefficient, T _SurfaceAnd T _FlueBe respectively catalyst surface temperature (working as r=R) and body (bulk) effluent gas temperature (when r＞＞R), σ is a Stefan-Boltzmann constant, ε is catalyst surface emittance (catalystsurface emissivity).For the sake of simplicity, we have supposed that this catalyzer thermal conductivity, thermal diffusivity and slin emissivity keep constant.The stack gas performance of use under riser tube top and bottom condition is used for the Geankoplis relation of the isolating spheroid of air-flow and calculates this convective heat-transfer coefficient.Because difference＜20% of heat transfer coefficient is so use MV in whole this riser tube.Following table 1 has been listed physical constant and the catalyst performance that uses in this model.Table 1: model parameter

Except that Calculation of Heat Transfer, need satisfy the overall energy balance between granules of catalyst and the stack gas: H _Out-H _In+ Δ H ^o _Rxnξ+Q _Cat=0 H wherein _OutAnd H _InBe the stack gas enthalpy (for each time increment) under the entrance and exit condition, Δ H ^o _RxnBe because the enthalpy change that the reaction of the methane of ζ mole causes, Q _CatBe the heat that during time increment, passes to this catalyzer.Use following equation to calculate the enthalpy of gaseous mixture: H-H ₂₉₈(kJ/mol)=At+Bt ²/ 2+Ct ³/ 3+Dt ⁴/ 4-Et+F-H (wherein t=T (K)/1000) wherein A to H is the thermal capacitance constant of predetermined substance.The calculating of the effluent gas temperature that this energy-balance equation allows axially to make progress along this riser tube.

These heat transfer PDE use explicit (explicit), method of finite difference to carry out numeral and find the solution. $\frac{\∂c}{\∂\mathrm{\τ}}=\frac{1}{R^2}\frac{\∂}{\∂R}\left(R^2\frac{\∂c}{\∂R}\right)\mathrm{Where\; c}=\frac{T}{T_o},\mathrm{\τ}=\frac{\mathrm{Dt}}{a^2},R=\frac{r}{a}$ $c_{i,j+1}=c_{\mathrm{Ij}}+\frac{\∂\mathrm{\τ}}{i{(\∂R)}^2}\{(i+1)c_{i+1,j}-2i{c}_{i,j}+(i-1)c_{i-1,j}\},i\≠0$ $c_{i,j+1}=c_{\mathrm{Ij}}+\frac{6\∂\mathrm{\τ}}{{(\∂R)}^2}\{c_{1,j}-c_{0,j}\},i=0$ $c_{N,j+1}=c_{\mathrm{Nj}}+\frac{\∂\mathrm{\τ}}{N{(\∂R)}^2}\left\{(N+1)\right[c_{N-1,j}+2\mathrm{\α}\∂R(c_{N,j}^4-c_a^4)+2\mathrm{\β}\∂R(c_{N,j}-c_a)]-2N{c}_{N,j}+(N-1)c_{N-1,j}\}$ Wherein subscript i is 0 to N radially index, and subscript j is a time index, and subscript a representes the stack gas performance, and α and β are respectively nondimensional radiation and convection boundary condition constant. Situation A: all air adds in the riser tube bottom

The catalyst temperature that Fig. 5 shows as the inner different radial positions of this granules of catalyst of the function of the catalyzer residence time in the riser tube distributes.These distributions are to be that the catalyzer of 3650 μ m generates for diameter (a), and it is representative for sedimentation bed (non-fluidisation) reactor drum.Initial effluent gas temperature when the time is zero is 2254 ℃ a thermal insulation warming.This granules of catalyst reaches 850 ℃ the equal temperature of matter (mass averagetemperature) after 0.95 second, but still has significant internal temperature gradient at this moment.0.95 after second, this granules of catalyst leaves this riser tube and breaks away from this stack gas, then these inner gradients reach balance, and wherein hypothesis is no longer conducted heat with process gas.After about 3.5 seconds, this granules of catalyst is issued to balance at 850 ℃.Because initial high effluent gas temperature, this catalyst surface temperature is higher than desirable 850 ℃ far away, after 0.05 second, reaches maximum 1073 ℃.Should be noted that for capturing events exactly under short time scale, the time step of using in this numerical simulation is 0.0004 second. Case B: air is along the axial distribution of riser tube

The catalyst temperature that Fig. 6 shows as the inner different radial positions of this granules of catalyst of the function of the catalyzer residence time in the riser tube distributes.These distributions are to be the catalyzer generation of 3650 μ m (like Fig. 5) for identical diameter.Air distributes (the about 3.5ft of each decanting point) along this riser tube, and the amount of the air that adds at each decanting point is decided by the amount of getting back to 1000 ℃ of desired energy that this effluent gas temperature is raise.After having used all available air, the oxygen that do not reinject, this stack gas is through cooling off with solid heat transfer.Consistent with the hot motivating force that reduces, this granules of catalyst reaches 850 ℃ the equal temperature of matter after 1.96 seconds, and this roughly is the twice of situation A (wherein at all air of riser tube bottom injection) required time amount.Yet 904 ℃ maximum surface temperature significantly is lower than 1073 ℃ of situation A.This method can minimize the exposure of catalyzer under very high temperature, thereby help to reduce because the catalyst deactivation that the variation of sintering, volatilization or avtive spot causes, and because the thermal gradient that reduces has been improved its mechanical integrity. Embodiment 2: the control of maximum catalyst surface temperature

The hydrothermal deactivation aspect that makes catalyst surface temperature be minimized in catalyzer in the restriction riser tube is important.Two possibly be (1) the highest effluent gas temperature (handling through changing to inject to distribute along the air of this riser tube) and (2) catalyst grain size to distribute factor with remarkably influenced of catalyst surface temperature.Other catalyzer and fluid characteristics (as, thermal conductivity, slin emissivity, convective heat-transfer coefficient, thermal capacitance or the like) possibly influence catalyst temperature and distribute, but from catalyzer and/or reactor design aspect more difficulty control.This embodiment proof can make catalyst surface temperature minimize through handling effluent gas temperature (for the specific catalyst granularity).In following simulation; We use " continuously " air decanting point to keep fixed effluent gas temperature (up to having used all air) down at infinitesimal catalyzer time period of stay (perhaps riser tube length); Thereby performance modeling theory, best (that is the minimum required residence time).

Table 2 shows 250 representative μ m under 3650 representative under analog result (1) the sedimentation bed bioreactor situation of two kinds of granularities μ m and (2) fluidized-bed reactor situation.For the selection of fixed granularity with initial effluent gas temperature, table 2 shows particle and during heating is increased to 850 ℃ of desired short residence time(SRT)s with the maximum surface temperature of experience with the average grain temperature.For the extreme case that all air are injected in this riser tube bottom; The maximum surface temperature that the particulate of 250 μ m is 871 ℃ is markedly inferior to 1073 ℃ of 3650 μ m particulate, and this is owing to their higher surface-to-volume ratios example and shorter transmission size.In addition, for smaller particles, the needed residence time also reduces significantly.Under the fixed granularity, the initial effluent gas temperature that reduces in the isothermal region has reduced this maximum catalyst surface temperature and has increased the needed residence time.For the extreme case of constant in the whole riser tube (under 900 ℃), 250 μ m particulate maximum surface temperatures are only high 5 ℃ than final medial temperature, and are high 22 ℃ for 3650 μ m particles for this effluent gas temperature.Can use rational riser tube height and particle speed to realize for the required residence time of these granularities and effluent gas temperature.

Though invention has been described and explanation with reference to specific embodiment, those skilled in the art will appreciate that the present invention is applicable to not necessarily the variation of explanation in this article.Therefore, should only confirm true scope of the present invention according to appended claims. Table 2: maximum catalyst surface temperature is to the dependency of granularity and effluent gas temperature

Claims (25)

1. being used for methane conversion is the method that comprises the more higher hydrocarbon of aromatic hydrocarbon, and this method comprises:

(a) making the charging that comprises methane and dehydrocyclization catalyst is to contact under the condition of aromatic hydrocarbon effectively making said methane conversion in reaction zone;

(b) first part with said catalyzer is transferred to the heating zone from this reaction zone;

(c) in this heating zone,, this catalyzer heats this first catalyst member through being contacted with the hot combustion gas that produces through the combustion fuel supplementary source; Wherein the temperature of this hot combustion gas is 800 ℃-1300 ℃; Operate under the pressure of 69-690kPa this heating zone, and " fuel refreshment source " is meant that this fuel source physically separates with catalyzer; With

First catalyst member that (d) will heat returns to this reaction zone.

2. the process of claim 1 wherein said first catalyst member is directly contacted with said fuel source.

3. the process of claim 1 wherein with isolating combustion zone, said heating zone in the said fuel source of burning and the combustion gases that will in this combustion zone, produce be fed to this heating zone.

4. the method for above-mentioned arbitrary claim, wherein said fuel refreshment source comprises hydrocarbon and/or hydrogen.

5. the method for claim 4, wherein said fuel refreshment source comprises hydrocarbon, and in oxygen-lean atmosphere the said hydrocarbon of burning to produce synthetic gas.

6. the method for above-mentioned arbitrary claim wherein prolongs said heating zone and applies heat in a plurality of positions of separating along the length of this heating zone to said first catalyst member.

7. the method for claim 6 wherein offers all basically postcombustions one end of this heating zone and in the position of said a plurality of separations oxygen-containing gas is offered said heating zone with increasing gradually

8. the method for claim 6, wherein will with isolating combustion zone, said heating zone in the hot combustion gas that produces offer the position of said a plurality of separations.

9. the method for above-mentioned arbitrary claim, wherein said heating zone are riser tubes and make said first catalyst member upwards through this riser tube.

10. each method during aforesaid right requires, the temperature of wherein said first catalyst member when getting into said heating zone are that 500 ℃-900 ℃ and the temperature when leaving said heating zone are 800 ℃-1000 ℃.

11. the method for above-mentioned arbitrary claim also comprises making said first catalyst member experience stripping step therefrom to remove coke and/or heavy hydrocarbon at least in part.

12. the process of claim 1 wherein that said stripping step comprises makes said first catalyst member and steam, hydrogen and/or CO ₂Contact.

13. the method for claim 1 or claim 12, wherein said stripping carries out in said heating (c) afterwards.

14. the method for above-mentioned arbitrary claim comprises that also first catalyst member that makes this heating contacts with methane therefrom to remove the water and/or the oxygen of absorption at least in part.

15. the method for above-mentioned arbitrary claim, wherein said catalyst pack containing metal and make first catalyst member experience carburization step of this heating.

16. the method for above-mentioned arbitrary claim; Comprise that also the second section with this catalyzer is transferred to and isolating breeding blanket, said heating zone, and make said second catalyst member in said breeding blanket, contact the coke that produces through said contact (a) to remove with regeneration gas.

17. the method for claim 16, the temperature in the wherein said breeding blanket are 400 ℃-700 ℃.

18. each method in claim 16 or 17, the ratio of weight and the weight of the catalyzer that in the identical time, is transferred to this breeding blanket that wherein in preset time, is transferred to the catalyzer of this heating zone is 5: 1-100: 1.

19. each method among the claim 16-18, wherein said regeneration gas comprises oxygen.

20. each method among the claim 16-19, wherein said breeding blanket are riser tube or moving-bed.

21. each method among the claim 16-20 wherein makes this regenerated second catalyst member experience carburization step.

22. the method for above-mentioned arbitrary claim, wherein said charging in said reaction zone with the moving-bed contacting of said dehydrocyclization catalyst.

23. each method among the claim 16-22; Wherein said reaction zone comprises vertically arranged sedimentation bed bioreactor; Wherein said charging gets into this reactor drum near the bottom of this reactor drum or its, and at the top of this reactor drum or near first catalyst member that will heat it and this regenerated second catalyst member return to this reactor drum.

24. each method among the claim 1-21, wherein said charging contact with one or more fluidized-beds of said dehydrocyclization catalyst in said reaction zone.

25. the method for claim 24; Wherein said reaction zone comprises a plurality of fluidized-bed reactors that are connected in series; Wherein first catalyst member of this heating is fed to first reactor drum in the said series connection, and be introduced in said the series connection in final reactor in said charging move upstream.

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