CA3123146C - Method for aromatization of propane and butane - Google Patents

Abstract

A method for aromatization of propane and butane includes: carrying out a catalytic dehydrogenation reaction of propane and butane under the action of a dehydrogenation catalyst to obtain a dehydrogenation reaction product; and carrying out an aromatization reaction of the dehydrogenation reaction product under the action of a catalyst to obtain an aromatization product. Wherein, a reaction-regeneration device for dehydrogenation of alkane is provided; a regenerator is arranged above a reactor; a spent catalyst riser pipe extends into a dilute- phase section of the regenerator from the top of the reactor; and a regenerated catalyst delivery pipe extends into the reactor from the bottom of the regenerator. The method improves the conversion rate of alkane, and the generated olefins are further aromatized to produce naphtha rich in aromatic hydrocarbons. The dehydrogenation reactor and the regenerator are arranged up and down, so the structure is compact and the occupied space is small.

Description

Description Method for Aromatization of Propane and Butane The application claims priority from Chinese Patent Application No.
CN202011478719.8 filed on Dec. 15, 2020.
TECHNICAL FIELD
The present application relates to a method for an aromatization reaction mainly based on propane and butane, and specifically relates to a method for implementing aromatization after olefin preparation through dehydrogenation of propane and butane so as to produce naphtha.
BACKGROUND
It is well known that low-carbon alkanes are abundant in resources and low in price.
The by-product liquefied petroleum gas of refinery enterprises in China is rich in a large amount of propane and butane. At present, there is a big gap between the separation technologies for propane and butane and deep processing and utilization of its downstream products in China and those of the United States, Europe, Japan and other countries. Most of propane and butane are burned as a civil fuel, resulting in waste of resources. It can be seen that it is a challenge in the refining and chemical industry today how to effectively utilize a large number of propane and butane resources produced by oil fields and produced as by-products of petrochemical plants.
Meanwhile, the demand for light aromatic hydrocarbons being as important petrochemical raw materialsõ such as benzene, toluene and xylene (BTX) increases year by year with quick development of the three major synthetic materials (synthetic rubber, synthetic fiber, synthetic resin) and other fine chemicals. In addition, the demand for high-octane gasoline in fuel markets is growing rapidly, and light aromatic hydrocarbon is important blending components of high-octane gasoline, so it is particularly necessary to Date Recue/Date Received 2021-06-23 develop production technologies for aromatic hydrocarbons.
Naphtha is used as a main raw material for traditional production of light aromatic hydrocarbons, which are prepared by using a catalytic reformer. A catalytic reforming technology is a main way for a refinery enterprise to obtain blending components for high-octane gasoline and high-quality aromatic hydrocarbons. According to this technology, straight-run naphtha components are converted into aromatic hydrocarbons through reactions such as dehydrogenation, isomerization dehydrogenation and cyclization dehydrogenation under the action of catalysts PtRe/C1-A1203 or PtSn/C1-A1203.
Catalytic reforming has relatively high requirements on the potential content of aromatic hydrocarbons and the content of impurities in the raw materials. In addition, with gradual increment of a market demand for light aromatic hydrocarbons and limited supply of conventional naphtha resources, the market demand on light aromatic hydrocarbons cannot be satisfied.
An aromatization technology is a petroleum processing technology developed in recent years, in which low-carbon hydrocarbons are converted into light aromatic hydrocarbons such as BTX, etc. under the action of a modified zeolite catalyst (ZSM-5 zeolites modified by Zn or Ga, etc.). In terms of raw materials, compared with olefins with the same carbon number alkanes, it is difficult for alkanes to generate carbonium ions and alkanes are low in aromatization activity. Therefore, when raw materials with high alkane content are used, endothermic cracking or dehydrogenation reaction is required to generate carbonium ions during activation, and thus the activated raw materials undergo an oligomerization cyclization reaction to generate aromatic hydrocarbons. In recent years, scholars have carried out a lot of research work on the aromatization of propane and butane, optimizing the reaction process conditions, improving the catalysts by various methods such as hydrothermal treatment, so as to improve the aromatization activity and stability of the catalysts and enhance the carbon deposition resistance of the catalysts.
Nevertheless, the aromatization of propane and butane generates a large amount of methane and ethane by-products due to cracking. Ethane is more difficult to aromatize due

2 Date Recue/Date Received 2021-06-23 to its lower reaction activity, so this part of dry gas cannot be used with a high value, the economic evaluation of the device is poor. This limitation causes difficulty in promotion of this technology.
Based on the above-mentioned development situation, the present application proposes a method and an improved device for an aromatization reaction of olefins produced by a dehydrogenation reaction of propane and butane to partially or completely improve the above-mentioned problems.
SUMMARY
A purpose of the present application is to increase the conversion rate of catalytic dehydrogenation of alkane.
Another purpose of the present application is to efficiently implement an aromatization reaction from propane and butane produced in oil fields or in petrochemical plants.
Another purpose of the present application is to increase the conversion rate of dehydrogenation of propane and butane, thereby increasing the conversion rate of aromatization.
On one hand, the first purpose of the present application is achieved by a method for catalytic dehydrogenation of alkane; The method comprises: carrying out a dehydrogenation reaction of alkane under the action of a dehydrogenation catalyst to obtain a dehydrogenation reaction product, wherein an active component in the dehydrogenation catalyst includes at least one element selected from a group consisting of In, Ge, Al, Bi, and Ru.
In other words, in the dehydrogenation catalyst, the active component does not contain the elements Pt, Cr or V except for the above-mentioned elements, or the content of the Pt, Cr or V element is lower than a detection limit of atomic absorption spectroscopy specified by IUPAC.

3 Date Recue/Date Received 2021-06-23 A method for preparing the dehydrogenation catalyst comprises: carrying out a reaction of a substance containing at least one element selected from a group consisting of In, Ge, Al, Bi and Ru with water; and then carrying out heating treatment to obtain the catalyst.
The substance containing element of In, Ge, Al, Bi, or Ru is a kind of elementary substance, alloy, carbon oxide or nitrogen oxide.
A temperature of the reaction of the substance containing at least one element selected from a group consisting of In, Ge, Al, Bi and Ru with water is in a range of 20 DEG C to 900 DEG C; preferably, the temperature of the reaction is in a range of 20 DEG
C to 300 DEG C; and more preferably, the temperature of the reaction is in a range of 100 DEG C to 200 DEG C. A reaction time is in a range of 0.5 h to300 h, preferably the reaction time is in a range of lh to 100 h.
In one embodiment, according to the method, the substance containing the element of In, Ge, Al, Bi or Ru is firstly soaked in acid liquor/alkaline liquor before reacting with water.
The acid liquor is selected from inorganic acids or organic acids, preferably the inorganic acids. The alkaline liquor is selected from inorganic bases or organic bases, preferably the inorganic bases.
A molar concentration of the inorganic acids or inorganic bases is in a range of 0.01%
to 20.0%, preferably 0.02% to 5.0%.
Alternatively, a method for preparing the dehydrogenation catalyst comprises:
loading the substance containing at least one element selected from a group consisting of In, Ge, Al, Bi and Ru on a carrier; and then carrying out a process for heating treatment to obtain the catalyst.
The reaction of loading the substance containing the element selected from a group consisting of In, Ge, Al, Bi and Ru on the carrier comprises an immersion method, a sol-gel method, a precipitation method, a hydrothermal method, a combustion method, a complexing method, a solvothermal method, a sonochemical method, a spraying method,

4 Date Recue/Date Received 2021-06-23 a roller coating method or an ion exchange method. The reaction is not limited to utilize the above-mentioned methods, and other methods for preparing catalyst may also be selected.
A content of the substance contained in the catalyst is in a range of lOwt% to wt%.
Generally the content of active component in the catalyst refers to the weight of metallic oxide in the highest valence state.
In the preparation method of the dehydrogenation catalyst, the substance containing the element selected from a group consisting of In, Ge, Al, Bi, or Ru is a kind of an elementary substance, alloy, carbon oxide, nitrogen oxide, nitrate, sulfate or chloride.
The carrier is selected from one or more materials selected from a group consisting of a zeolite, SiO2, MgO, ZnA1204, Zn(Gai_x)A1x04, Mg(Ga1_4A1x04, MgA1204, TiO2, Ga203, Ce02 and a hollow ceramic sphere. The zeolite is selected from A zeolites, X
zeolites, Y
zeolites, M zeolites, ZSM zeolites, aluminum phosphate zeolites, HMS zeolites, SBA
zeolites, M4 1 s zeolites and isomorphous substitution of Al and Si zeolites by heteroatoms containing P and Ti.
In the above-mentioned two methods for preparing the dehydrogenation catalyst, the process of heating treatment includes drying and/or roasting. A drying temperature is in a range of 50-300 DEG C, preferably in a range of 80-180 DEG C. A roasting temperature is in a range of 300-1100 DEG C, preferably in a range of 500-700 DEG C.
In some embodiments, the method further includes the step of adding an additive to the reactants before reaction, or soaking a prepared catalyst in the additive.
The additive is a compound including one or more elements selected from a group consisting of alkaline metals, alkaline earth metals, Ni, Cu, La, Y, Ce, Fe, and Zr.
An amount of the additive is in range of 0% to 30% of the substance (dry basis), and preferably the amount is in range of 0.005 wt% to10 wt%.
The additive is a compound including one or more elements selected from a group consisting of Ni, Cu, La, Y, Ce, Fe, and Zr.

5 Date Recue/Date Received 2021-06-23 The dehydrogenation catalyst prepared by the above-mentioned two methods has a shell layer with a specific surface area in a range of 100-400 m2/g and a pore volume in a range of 0.05-0.1 cm3/g.
For the catalyst with a shell layer structure, the transfer and supplementation between a surface material and lattice oxygen in a bulk-phase material is blocked, the pretreatment time and induction period of the catalyst are effectively shortened, and the heat transfer efficiency of the catalyst is improved as well. In addition, the shell layer structure of the catalyst has a dehydrogenation active surface with a relatively large specific surface area and a relatively short diffusion path. So the pretreatment time and induction period of the catalyst can be further shortened and simultaneously the mass transfer efficiency is improved.
The pore diameter of the shell layer of the dehydrogenation catalyst is in a range of 3nm to 10 nm.
The shell layer of the catalyst has the characteristics of being stable in structure and not prone to falling off, so that the catalyst can still maintain an excellent dehydrogenation effect after repeated regeneration.
In some embodiments, aluminum oxide is as a dehydrogenation active center of the dehydrogenation catalyst.
In the present application, a reaction temperature of catalytic dehydrogenation of alkane is in a range of 500 to 660 DEG C.
A pressure at the top of the reactor is in a range of 0.1MPa to 0.5 MPa (absolute pressure), and a mass space velocity is in a range of 0.110 to 5 11-1.
A conversion rate of alkane and the selectivity of olefin in a single-pass can be improved via using the dehydrogenation catalyst.
In the present application, the number of carbon atoms of alkane is generally no more than 6; preferably the number of carbon atoms of alkane is in a range of 2 to 4.
Furthermore, the following reaction-regeneration device for dehydrogenation of alkane is utilized to increase the conversion rate of alkane with low energy consumption.

6 Date Recue/Date Received 2021-06-23 The reaction-regeneration device for dehydrogenation of alkane of the present application can also be combined with any dehydrogenation catalyst in the prior art.
A reaction-regeneration device for dehydrogenation of alkane of the present application includes:
a reactor, a regenerator arranged above the reactor, a spent catalyst riser pipe, being a straight pipe extending in an axial direction of the reactor; a first end of the spent catalyst riser pipe being located in a lower part of the reactor; a second end of the spent catalyst riser pipe being in the regenerator from a top of the reactor;
a regenerated catalyst delivery pipe, being a straight pipe extending in the axial direction of the reactor; a first end being located in the regenerator; a second end of the regenerated catalyst delivery pipe being in the reactor from a bottom of the regenerator;
and a lifting medium pipe, a first end of the lifting medium pipe being arranged outside the reactor; and a second end of the lifting medium pipe being located inside the spent catalyst riser pipe.
The regenerator includes a regeneration section and a settling section; and the reactor comprises a reaction section and a settling section.
A lifting medium is introduced into the lifting medium pipe to drive a spent catalyst at the bottom of the reactor to move upwards, and the spent catalyst enters the regenerator through the spent catalyst riser pipe.
In a preferable embodiment, the second end of the lifting medium pipe is located above an opening of the first end of the spent catalyst riser pipe. When the lifting medium is introduced, a negative pressure zone is generated near the first end of the spent catalyst riser pipe, and the spent catalyst at the bottom of the reactor can be sucked into the spent catalyst riser pipe.
In one embodiment, a gas stripping medium is introduced into the lower part of the

7 Date Recue/Date Received 2021-06-23 reactor to strip off oil gas carried by the spent catalyst falling into the bottom of the reactor, and thus oil gas loss is reduced.
In a preferable embodiment, a gas stripping medium distributor is arranged at the lower part of the reactor and is located above the first end of the spent catalyst riser pipe.
The gas stripping medium is introduced into the gas stripping medium distributor to strip off the oil gas carried by the spent catalyst falling into the bottom of the reactor.
The gas stripping medium distributor is one pipe in an annular shape or more pipes in annular shapes arranged on a same plane; and nozzles are arranged on the pipe(s).
In addition, under the driving of the lifting medium, the spent catalyst is well suctioned and pushed around the bottom of the spent catalyst riser pipe while continuously moving upwards along the spent catalyst riser pipe, and the cyclic driving force for the catalyst is great. Therefore, the circulation amount of the catalyst is increased, and the catalyst-gas ratio is increased, which is beneficial to conversion of alkane molecules.
In some embodiments, the first end of the spent catalyst riser pipe is close to the bottom of the reactor. After falling into the bottom of the reactor, the deactivated catalyst can be quickly delivered to the regenerator to be regenerated, thus occurrence of a side reaction is reduced, and the selectivity of olefin is improved.
In one embodiment, the second end of the spent catalyst riser pipe is configured to be stuck into a dilute-phase section of the regenerator. Namely, the second end of the spent catalyst riser is located at the lower part of the settling section of the regenerator.
In one embodiment, the second end of the regenerated catalyst delivery pipe is located in the reactor and located below the settling section of the reactor.
A raw material distributor is arranged at the lower part in the reaction section of the reactor, and the second end of the regenerated catalyst delivery pipe is located above the raw material distributor. Thus, the regenerated catalyst in the reactor is in countercurrent contact with raw materials, the distribution of the residence time of the catalyst particles in the reactor is narrow, and the degree of back mixing is low. During the contact between

8 Date Recue/Date Received 2021-06-23 the raw materials and the catalyst, the content of an active catalyst in a unit contact area is higher, which can increase the conversion rate of the raw materials.
In some embodiments, the raw material distributor is one pipe in an annular shape or more pipes in annular shapes which are arranged on the same plane, and nozzles are arranged on the pipe(s). The directions of the nozzles can be upward or downward.
In the reaction-regeneration device for dehydrogenation of alkane of the present application, most sections of the spent catalyst riser pipe and the regenerated catalyst delivery pipe are both arranged inside the reactor and the regenerator. In a catalyst delivery process, heat loss is reduced and energy consumption is greatly reduced. The reactor and the regenerator are arranged in up and down direction, so the structure is compact and the occupied space is small.
A gas stripping medium distributor and a fuel distributor are arranged in the regeneration section of the regenerator. The gas stripping medium distributor is located below the fuel distributor.
Both the gas stripping medium distributor and the fuel distributor are one pipe in an annular shape or more pipes in annular shapes which are arranged on the same plane, and nozzles are arranged on the pipe(s).
Cyclone separators, more preferably two-stage cyclone separators, are respectively arranged in the settling section of the regenerator and the settling section of the reactor.
Other components of the regenerator and the reactor can adopt the arrangement modes in the prior art, which are not repeated here.
On the other hand, another purpose of the present application is achieved by a method for dehydrogenation and aromatization of propane and butane, and the method comprising:
carrying out a catalytic dehydrogenation reaction of propane and butane to obtain a dehydrogenation reaction product; and carrying out an aromatization reaction of the dehydrogenation reaction product under the action of a catalyst to obtain an aromatization product,

9 Date Recue/Date Received 2021-06-23 wherein, the above-mentioned catalyst is used as the catalyst for catalytic dehydrogenation, and the reaction temperature is controlled to be in a range of 500 DEG C
to 660 DEG C. Other dehydrogenation catalysts of the prior art can be adopted as well.
Preferably, the above-mentioned dehydrogenation catalyst with the active component including at least one element selected from a group consisting of In, Ge, Al, Bi and Ru is used.
The catalytic dehydrogenation reaction of alkane in the present application is preferably carried out in the above-mentioned reaction-regeneration device for dehydrogenation of alkane.
In one embodiment, ZSM-5 zeolites are used as the catalyst in the aromatization reaction. Wherein, an atomic ratio of silicon to aluminum is larger than 10, a crystal size is in a range of lOnm to 300 nm, a specific surface area is larger than 150 m2/g, and a pore volume is in range of 0.25 cm3/g to 0.29 cm3/g.
Preferably, the atomic ratio of silicon to aluminum is larger than 30.
By reducing the acid center density (high silicon-to-aluminum ratio) and the crystal size (nano-scale), the accessibility of the active center is improved, and the micro-environment in the pores of the zeolites is improved, so as to increase the selectivity of gasoline components and delay coking deactivation.
Further, the ZSM-5 zeolites can be loaded with metal elements.
In some embodiments, the aromatization temperature is in a range of 360 DEG C
to 440 DEG C.
The pressure is in a range of 0.5 MPa to 1.0 MPa (absolute pressure), and the mass space velocity is in a range of 0.8 11-1 to 1.5 10.
In the present application, the dehydrogenation reaction of alkane is carried out in a fluidized bed, and the aromatization reaction of the dehydrogenation product is carried out in a fixed bed.
Propane and butane can be mixed according to any ratio.
According to the present application, propane and butane are used as raw materials, Date Recue/Date Received 2021-06-23 the dehydrogenation reaction and the aromatization reaction of alkane are combined to increase the conversion rate of aromatization and the yield of aromatic hydrocarbon, because more olefins are produced by the dehydrogenation reaction of alkane.
The aromatized product is absorbed by naphtha to produce the gasoline with low-olefin and high-octane. Alternatively the olefin of the aromatized product is hydrogenated and saturated to produce conventional naphtha which is convenient to transport or used for being blended with crude oil. The contradiction between supply and demand of aromatic hydrocarbon production is significantly alleviated, high-efficiency conversion of low-carbon alkane resources is realized, the production cost is effectively reduced, and the comprehensive utilization level of oil gas resources is increased.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 illustrates an embodiment of the reaction-regeneration device for catalytic dehydrogenation of propane and butane according to the present application.
Fig. 2 illustrates a flow chat of the aromatization after catalytic dehydrogenation of propane and butane according to the present application.
Fig. 3 is schematic view of the pipe in annular shape (including the feeding annular pipe in the reactor, the gas stripping medium annular pipe, as well as the annular pipe which is used for introducing the fuel or the gas stripping medium into the regenerator).
DETAILED DESCRIPTION
A method for aromatization from propane and butane as raw materials of the present application is further described below in detail. The protection scope of the present application is not limited and is defined by the claims. The disclosed specific details provide a comprehensive understanding of each disclosed embodiment. However, those skilled in the relevant art know that the embodiments can also be implemented by using other materials and the like without using one or more of these specific details.
Unless there is required by the context, in the description and claims, the terms Date Recue/Date Received 2021-06-23 "comprising" and "including" should be understood as open meaning of comprising, that is," including, but not limited to".
The "embodiment", "one embodiment", "another embodiment" or "some embodiments" mentioned in the description refer to that the described specific features, structures or characteristics related to the embodiments are included in at least one embodiment. Therefore, "the embodiment," "one embodiment," "another embodiment," or "some embodiments" do not need to refer to the same embodiment. Moreover, specific features, structures or characteristics can be combined in any manner in one or more embodiments. Each feature disclosed in the description can be replaced by any alternative feature that can provide the same, equal or similar purpose. Therefore, unless otherwise specified, the disclosed features are only general examples of equal or similar features.
The experimental methods that do not indicate specific conditions in the following embodiments usually refer to the conventional conditions or the conditions recommended by the manufacturer. Unless otherwise specified, all percentages, ratios, proportions, or parts are calculated based on the weight.
The term "aromatization" refers to the conversion of low-molecular-weight hydrocarbons into mixed aromatic hydrocarbons containing benzene, toluene and xylene through an aromatization reaction under the action of a catalyst, and meanwhile a gas phase containing hydrogen, methane and C2-05 fractions is generated. After being separated, mixed aromatic hydrocarbons, light aromatic hydrocarbons and heavy aromatic hydrocarbons that meet the standards are finally produced.
'Naphtha" is also called as crude gasoline, which generally contains alkane, monocyclic alkane, bicyclic alkane, alkylbenzene, benzene, indane and tetralin. The main components are C5¨C7 of alkane.
Embodiment 1 According to this embodiment, the dehydrogenation catalyst is prepared by the following method.
20.0 g of aluminum powder (Al) was added to a 0.15 mo1.1:1 NaOH solution to be Date Recue/Date Received 2021-06-23 soaked for 5 minutes. After being filtered, washed with deionized water, the above treated aluminum was transferred to a reaction kettle with a PTFE lining and a volume of 250 mL, and mixed with 150 mL of deionized water. The reaction kettle containing the mixture was sealed, allowed to stand in an oven at 120 DEG C for 12 h. The materials in the reaction kettle was taken out and dried in the oven at 120 DEG C to obtain the dehydrogenation catalyst for later use.
The prepared catalyst was subjected to being pre-reduced in an H2 (30 mL=min-1) atmosphere for 1 h, and then was in contact with propane for reaction at the reaction temperature 600 DEG C and the mass space time 4.46 h. The initial conversion rate, propylene selectivity and coke yield of the catalyst were tested respectively, wherein the initial conversion rate is 38.2%, the propylene selectivity is 64.3%, and the coke yield is 5.6%.
Embodiment 2 According to this embodiment, the dehydrogenation catalyst is prepared by the following method:
2.5 g of aluminum chloride (A1C13) and 1.0 g of ruthenium chloride (RuC13.3H20) were dissolved in 100 g of water to form a solution A; 10 g of an all-Si zeolite was added to 100 g of water and stirred at 60 DEG C to form suspension liquid B. The solution A was dropped into the suspension liquid B to get a mixture; the pH of the mixture was adjusted .. to about 9 with ammonia water; and then a certain amount of polyethylene glycol was added as a dispersant to get a second mixture. The second mixture was subjected to reaction in a water bath for 2 h, and subjected to filtration and washing until no chlorine ions was detected by using silver nitrate, and then a solid product without chlorine ions was obtained. The solid product was carried out drying at 120 DEG C and roasting at 600 DEG C for 4 hours to obtain the dehydrogenation catalyst.
The prepared catalyst was subjected to being pre-reduced in a CO (30 mL.min-1) atmosphere for 0.5 h, and then was in contact with propane for reaction at the reaction temperature 600 DEG C and the mass space time 4.46 h. The initial conversion rate, Date Recue/Date Received 2021-06-23 propylene selectivity and coke yield of the catalyst were tested respectively, wherein the initial conversion rate was 46.5%, the propylene selectivity was 75.2%, and the coke yield was 5.0%.
Embodiment 3 According to this embodiment, the dehydrogenation catalyst is prepared by the following method:
2.5 g of aluminum powder (Al), 2.5 g of ruthenium powder (Ru), 2.5 g of germanium powder (Ge) and 2.5 g of indium powder (In) were added to 0.15 mol=L-1 HNO3 solution to be soaked for 10 min, filtered, washed with deionized water, and transferred to a reactor with 250 mL and a PTFE lining. 150 mL of deionized water, 0.5 g of sodium bicarbonate (NaHCO3) as an additive, 5 g of tetrapropyl ammonium bromide and 10 g of SiO2 pellets were added in the reactor to obtain a mixture. The mixture was sealed in the reactor, allowed to stand in an oven at 150 DEG C for 6 h, and taken out. After drying, the SiO2 pellets (named as CAT-1) and matrix products (homogeneous growth, named as CAT-2) were sieved out, and both were roasted at 600 DEG C for 4 h.
The prepared catalyst CAT-1 was subjected to being pre-reduced in a CO (30 mL=min-1) atmosphere for 0.5 h and then was in contact with propane for reaction at the reaction temperature 600 DEG C and the mass space time 4.46 h. The initial conversion rate, propylene selectivity and coke yield of the catalyst were tested respectively, wherein the initial conversion rate is 38.0%, the propylene selectivity was 86.3%. The catalytic property of the catalyst slowly declined after about 16 h of reaction of the catalyst, and the coke yield was about 2.1%.
The prepared catalyst CAT-2 was subjected to being pre-reduced in a CO (30 mL=min-1) atmosphere for 0.5 h and then was in contact with propane for reaction at the reaction temperature 600 DEG C and the mass space time 4.46 h. The initial conversion rate, propylene selectivity and coke yield of the catalyst were tested respectively, wherein the initial conversion rate was 43.3%, the propylene selectivity was 82.3%.
The catalytic property of the catalyst slowly declined after about 9 h of reaction of the catalyst, and the Date Recue/Date Received 2021-06-23 coke yield was about 3.7%.
Specific Surface Pore Volume Pore Diameter Area (m2/g) (cm3/g) (nm) Embodiment 3 (CAT-1) 320.20 0.89 8.41 Embodiment 3 (CAT-2) 160.21 0.15 3.91 Embodiment 4 The dehydrogenation-regeneration reaction device for alkane as shown in Fig. 1 includes a reactor and a regenerator, wherein the regenerator is arranged above the reactor.
The reactor includes a reactor reaction section 7 and a reactor settling section 9; and the regenerator includes a regenerator regeneration section 17 and a regenerator settling section 18.
The cross sections of the reactor and the regenerator are both circular.
io A spent catalyst riser pipe 8 is a straight pipe extending in the axial direction of the reactor. The first end of the spent catalyst riser pipe 8 is located in the reactor reaction section 7; and the second end of the spent catalyst riser pipe 8 is located in the regenerator through the top of the reactor. A regenerated catalyst delivery pipe 11 is a straight pipe extending in the axial direction of the reactor. The first end of the regenerated catalyst delivery pipe 11 is located in the regenerator; and the second end of the regenerated catalyst delivery pipe 11 is located in the reactor through the bottom of the regenerator.
In this embodiment, the first end of the spent catalyst riser pipe 8 is close to the bottom of the reactor; and the second end of the spent catalyst riser pipe 8 is located in the dilute-phase section of the regenerator regeneration section.
The first end of the regenerated catalyst delivery pipe 11 is close to the bottom of the regenerator. A regenerated catalyst can be conveniently conveyed into the second end located in the reactor through the first end of the regenerated catalyst delivery pipe 11, and then enters the reactor.
Control valves are arranged at appropriate positions in the spent catalyst riser pipe 8 and the regenerated catalyst delivery pipe 11 to facilitate to control the flow rate of the Date Recue/Date Received 2021-06-23 catalyst. In this embodiment, the control valves (111, 81) of both the spent catalyst riser pipe 8 and the regenerated catalyst delivery pipe 11 are located at positions outside the regenerator and the reactor.
Reactor:
A lifting medium pipe 2 is further arranged in the reactor; the first end of the lifting medium pipe 2 is arranged outside the reactor; and the second end of the lifting medium pipe 2 is located in the spent catalyst riser pipe 8. A lifting medium is introduced into the lifting medium pipe 2; negative pressure is generated near the first end of a spent catalyst riser pipe; a spent catalyst at the bottom of the reactor is sucked into the lifting medium pipe 2; and the spent catalyst is driven to be lifted and enter the regenerator. The lifting medium is selected from water vapor or nitrogen.
A feed distributor 6 for conveying a raw material 5 is arranged in the reactor reaction section 7, and a gas stripping medium distributor 4 for conveying a gas stripping medium 3 is arranged under the feeding distributor 6. Both the feed distributor 6 and the gas stripping medium distributor 4 are pipes in annular shapes; and nozzles are arranged on the pipes in annular shapes. The raw material 5 or a gas medium is sprayed into the reactor through the nozzles of the pipes in annular shapes. The nozzles are arranged toward various directions.
The reactor settling section 9 is located above the reactor reaction section 7. The reactor reaction section is divided into a dense-phase section and a dilute-phase section;
and the dilute-phase section is located above the dense-phase section. The second end of the regenerated catalyst delivery pipe 11 is preferably located in the dilute-phase section of the reactor reaction section.
A cyclone separator 10 is arranged in the reactor settling section 9 to separate the catalyst from oil gas. The top of the reactor is provided with an oil gas outlet 12, and the oil gas is discharged out of the reactor through the oil gas outlet 12 after being separated from catalyst.
Re2enerator:

Date Recue/Date Received 2021-06-23 The regenerator regeneration section is divided into a dilute-phase section and a dense-phase section, and the dilute-phase section is located above the dense-phase section.
The second end of the spent catalyst riser pipe 8 is located in the dilute-phase section of the regenerator regeneration section. Through this arrangement, the spent catalyst is more likely to fall into the dense-phase section of the regenerator regeneration section for a regeneration reaction.
A gas stripping medium distributor 14 and an air and fuel distributor 16 are arranged in the lower part of the regenerator, and the air and fuel distributor 16 is located above the gas stripping medium distributor 14. Both the gas stripping medium distributor 14 and the air and fuel distributor 16 are pipes in annular shapes, and nozzles are arranged on the pipes in annular shapes. Air and fuel 15 or a gas stripping medium 13 is sprayed into the regenerator via the nozzles of the pipes in annular shapes. The nozzles are arranged toward various directions. The gas stripping medium may be water vapor or nitrogen, etc., preferably water vapor. A regenerated catalyst in the regenerator is stripped by the gas stripping medium 13, so that flue gas carried by the regenerated catalyst is lifted to the regenerator settling section, thereby the amount of flue gas carried by the catalyst into the reactor is reduced.
A cyclone separator 10 is arranged in the regenerator settling section 18 to separate the catalyst from flue gas. The top of the regenerator is provided with a flue gas outlet 19.
The flue gas is discharged out of the regenerator via the outlet 19 after the catalyst is separated from the flue gas.
All the pipes in annular shapes (including the feeding annular pipe in the reactor, the gas stripping medium annular pipe, as well as the annular pipe which is used for introducing the fuel or the gas stripping medium into the regenerator) are as shown in Fig.
3, and nozzles are arranged on the pipes in annular shapes. Preferably, the openings of the nozzles are upward.
Embodiment 5 The dehydrogenation-regeneration device for alkane of Embodiment 4 is used to Date Recue/Date Received 2021-06-23 implement a dehydrogenation reaction and a subsequent aromatization reaction.
The specific process flow is shown in Fig. 2.
Dehydro2enation reaction Propane and butane 5 as raw materials were fed in the reactor reaction section through the feed distributor 6 after being preheated, wherein the preheating temperature is in a range of 300 DEG C to 550 DEG C, preferably 350 DEG C to 500 DEG C. The raw materials are in contact with a dehydrogenation catalyst for reaction, and any one of Embodiments 1-3 is selected as the dehydrogenation catalyst. In the dehydrogenation reaction process, the reaction temperature is in a range of 500 DEG C to 660 DEG C, the pressure at the top of the reactor is in a range of 0.1 MPa to 0.5 MPa (absolute pressure), and the mass space velocity is in a range of 0.110 to 510.
The oil gas obtained is discharged from the reactor settling section 9 through the oil gas outlet 12. The spent catalyst is lifted by the lifting medium 1 to the spent catalyst riser pipe 8 and enters in the regenerator regeneration section 17. The air and fuel 15 are fed in the regenerator through the air and fuel distributor 16 to burn the spent catalyst for regeneration, wherein the regeneration temperature is in a range of 600 DEG C
to 750 DEG C. After being stripped by the gas stripping medium 13, the regenerated catalyst is delivered to the reactor 7 along the regenerated catalyst delivery pipe 11, and the flue gas is discharged from the flue gas outlet 19 on the top of the regenerator through the cyclone separator 10.
Aromatization reaction:
After heat exchange, the oil gas obtained in the dehydrogenation reaction is delivered in a water washing tower 20 to remove fine catalyst powder in the oil gas.
Water 22 containing the fine catalyst powder is sent to a sedimentation basin, the oil gas 23 after being removed from the fine catalyst powder enters a liquid separation tank 25 through a compressor 24. After oily sewage 26 is discharged, the oil gas 27 and oil 28 are subjected to heat exchange, and then enter an aromatization reactor 29 together. In the aromatization reaction, a conventional aromatization catalyst is adopted; the aromatization temperature Date Recue/Date Received 2021-06-23 is in a range of 360 DEG C to 440 DEG C; the pressure is in a range of 0.5 MPa to 1.0 MPa (absolute pressure); and the mass space velocity is in a range of 0.8 h1 to 1.5 h1. The aromatization catalyst SHY-02 comprises elements Ga and Pt, and a nano ZSM-5 zeolite, wherein, the content by weight of element Ga is 1.0%, and the content by weight of element Pt is 0.1%.
The oil gas 30 obtained in aromatization process is subjected to heat exchange, and then flows in a liquid separation tank 31 to obtain liquid-phase components and gas-phase components by gas and liquid separation. The liquid-phase components are pumped into an absorption and desorption tower 32 by using a pump, and the gas-phase components flow in an air compressor 24, and then is delivered in the absorption and desorption tower 32 after being compressed to 2 MPa. A part of naphtha 39 is used as absorbent oil, dry gas 34 is discharged from the top of the absorption and desorption tower, and absorbent oil 33 (naphtha rich in aromatic hydrocarbons) is discharged from the bottom of the absorption and desorption tower and enters a stabilization tower 35. The naphtha 39 is in the bottom of the stabilization tower, a part of the naphtha 39 is returned to the absorption and desorption tower 32 as absorbent oil, and another part is used as a product discharged from the device. The product at the top of the stabilization tower flows in a liquid separation tank 36 for separating liquid-phase components from gas-phase components.
Propane and butane 38 in the gas-phase components are recycled back to the dehydrogenation reactor 7 for the next cycle.
Aromatic hydrocarbons are prepared in combination with the aromatization reaction preparation process of Embodiment 5 below.
Experimental example 1:
The composition of raw materials is shown in Table 1. In the dehydrogenation reaction, the temperature is 580 DEG C; the catalyst prepared in Embodiment 1 is used as a dehydrogenation catalyst; the pressure at the top of the reactor is 0.18 MPa (absolute pressure); the mass space velocity is 3.0 h1. The product distribution after the dehydrogenation reaction in the dehydrogenation reactor 7 is listed in Table 2.

Date Recue/Date Received 2021-06-23 The oil gas obtained in the dehydrogenation reaction is fed in the aromatization reactor after dust removal, compression, and heat exchange. In the aromatization reaction, the temperature is 380 DEG C, the pressure is 0.8 MPa (absolute pressure), and the mass space velocity is 1.2 h1. The aromatization catalyst SHY-02 comprises elements Ga and Pt, and a nano ZSM-5 zeolite. In aromatization catalyst SHY-02, the content by weight of element Ga is 1.0%, the content by weight of element Pt is 0.1%. The aromatization product distribution is shown in Tables 3-4.
Experimental example 2:
The composition of raw materials is shown in Table 1. In the dehydrogenation reaction, the catalyst prepared in Embodiment 1 is used as a dehydrogenation catalyst; the temperature of the dehydrogenation reaction is 600 DEG C; the pressure at the top of the reactor is 0.15 MPa (absolute pressure); the mass space velocity is 2.5 h1.
The product distribution after the reaction in the dehydrogenation reactor 7 is listed in Table 2.
The oil gas obtained in the dehydrogenation reaction is fed in the aromatization reactor after dust removal, compression, and heat exchange. In the aromatization reaction, the temperature is 400 DEG C, the pressure is 0.7 MPa (absolute pressure), and the mass space velocity is 1.1 h1. The aromatization catalyst SHY-02 comprises elements Ga and Pt, and a nano ZSM-5 zeolite. In aromatization catalyst SHY-02, the content by weight of element Ga is 1.0%, and the content by weight of element Pt is 0.1%. The aromatization product distribution is shown in Tables 3-4.
Experimental example 3: 100% propane is used as a raw material. In the dehydrogenation reaction, the catalyst prepared in Embodiment 1 is used as a dehydrogenation catalyst; the temperature of the dehydrogenation reaction is 600 DEG C;
the pressure at the top of the reactor is 0.2 MPa (absolute pressure); and the mass space velocity is 3.5 h1. The product distribution after the reaction in the dehydrogenation reactor 7 is listed in Table 6.
The oil gas obtained in the dehydrogenation reaction is fed in the aromatization reactor after dust removal, compression, and heat exchange. In the aromatization reaction, Date Recue/Date Received 2021-06-23 the temperature is 380 DEG C, the pressure is 0.9 MPa (absolute pressure), and the mass space velocity is 1.3 111. The aromatization catalyst SHY-02 comprises elements Ga and Pt, and a nano ZSM-5 zeolite. In aromatization catalyst SHY-02, the content by weight of element Ga is 1.0%, and the content by weight of element Pt is 0.1%. The aromatization product distribution is shown in Tables 7-8.
Experimental example 4: The composition of raw materials is shown in Table 10.
In the dehydrogenation reaction, the catalyst prepared in Embodiment 1 is used as a dehydrogenation catalyst; the temperature of the dehydrogenation reaction is 580 DEG C;
the pressure at the top of the reactor is 0.15 MPa (absolute pressure); and the mass space velocity is 3.0 111. The product distribution after the reaction in the dehydrogenation reactor 7 is listed in Table 6.
The oil gas obtained in the dehydrogenation reaction is fed in the aromatization reactor after dust removal, compression, and heat exchange. In the aromatization reaction, the temperature is 400 DEG C, the pressure is 0.8 MPa (absolute pressure), and the mass space velocity is 1.210. The aromatization catalyst SHY-02 comprises elements Ga and Pt, and a nano ZSM-5 zeolite. In aromatization catalyst SHY-02, the content by weight of element Ga is 1.0%, and the content by weight of element Pt is 0.1%. The aromatization product distribution is shown in Tables 7-8.
Table 1 Composition of Raw Materials (wt%) No. Components Content 1 Ethane 4.83 2 Propane 38.98 3 Iso-butane 24.03 4 N-butane 27.92 5 Cis-2-butene 0.39 6 Iso-pentane 2.70 7 N-pentane 1.15 Date Recue/Date Received 2021-06-23 8 Sum 100.00 Table 2 Dehydrogenation Reactor Product Distribution (wt%) Components Experimental Example 1 Experimental Example 2 112 1.31 1.46 Methane 1.22 1.39 Ethane 5.18 5.08 Ethylene 1.43 1.72 Propane 27.28 26.17 Propylene 12.23 13.30 I so-butane 11.66 9.93 N-butane 15.52 14.21 Trans-2-butene 3.16 3.51 1-butene 2.52 2.80 I so-butene 11.54 13.22 Cis-2-butene 2.32 2.57 Butadiene 0.63 0.69 I so-pentane 1.23 1.25 N-pentane 0.63 0.65 C6+ 0.56 0.62 Coke 1.21 1.42 Table 3 Aromatization Reaction Product Distribution (wt%) Components Embodiment 1 Embodiment 2 Dry Gas 3.94 1.80 Propane 32.24 27.93 Propylene 0.20 0.17 I so-butane 19.21 21.87 Date Recue/Date Received 2021-06-23 N-butane 15.10 15.75 Butene 0.26 0.27 Liquid Yield of C(>5): 29.05 31.41 Table 4 Composition of Aromatization Reaction Liquid Product Family (wt%) Aroma Com Iso-alkan Cycloal Cyclool tic pone N-alkane N-olefin Iso-olefin Sum e kane efin Hydro nts carbon Embodiment 1 C5 8.06 20.37 0.98 0.00 0.14 0.17 0.00 29.73 C6 1.48 5.31 0.77 0.00 0.00 0.00 4.59 12.15 C7 0.22 2.27 1.41 0.00 0.00 0.00 17.28 21.17 C8 0.04 0.82 1.48 0.00 0.00 0.00 27.58 29.92 C9 0.10 0.22 0.54 0.00 0.00 0.00 5.98 6.83 C10 0.10 0.10 0.00 0.00 0.00 0.00 0.00 0.19 Sum 9.99 29.08 5.18 0.00 0.14 0.17 55.43 100.00 Embodiment 2 C5 9.21 22.80 0.73 0.00 0.16 0.16 0.00 33.05 C6 1.62 6.15 0.89 0.00 0.00 0.00 4.36 13.02 C7 0.22 2.24 1.40 0.00 0.00 0.00 16.27 20.13 C8 0.03 0.72 1.28 0.00 0.00 0.00 24.65 26.68 C9 0.10 0.16 0.39 0.00 0.00 0.00 6.34 6.99 C10 0.00 0.12 0.00 0.00 0.00 0.00 0.00 0.12 Sum 11.18 32.19 4.69 0.00 0.16 0.16 51.63 100.00 Table 5 Dehydrogenation Reactor Product Distribution (wt%) Components Embodiment 3 Embodiment 4 Date Recue/Date Received 2021-06-23 112 1.4 1.18 Methane 1.12 1.46 Ethane 1.18 1.18 Ethylene 0.73 0.51 Propane 61.28 0.81 Propylene 33 2.04 Iso-butane 0 27.05 N-butane 0 24.65 Trans-2-butene 0 4.40 1-butene 0 4.20 Iso-butene 0.36 25.55 Cis-2-butene 0 3.17 Butadiene 0 0.92 Iso-pentane 0.02 0.27 N-pentane 0.01 0.16 C6+ 0.08 0.99 Coke 0.82 1.47 Table 6 Aromatization Reaction Product Distribution (wt%) Components Embodiment 3 Embodiment 4 Dry Gas 1.57 1.73 Propane 21.43 30.22 Propylene 0.02 Iso-butane 0.89 18.93 N-butane 0.70 16.31 Butene 0.06 Liquid Yield of C(>5): 25.41 32.73 Date Recue/Date Received 2021-06-23 Table 7 Composition of Aromatization Reaction Liquid Product Family (wt%) Aroma Com Iso-alkan Cycloal Cyclool tic pone N-alkane N-olefin Iso-olefin Sum e kane efin Hydro nts carbon Embodiment 3 C5 12.48 21.83 0.84 0.00 0.09 0.15 0.00 35.39 C6 2.37 4.27 0.69 0.00 0.00 0.00 5.04 12.37 C7 1.37 3.01 1.39 0.00 0.00 0.00 15.21 20.98 C8 0.09 0.58 1.56 0.00 0.00 0.00 23.69 25.92 C9 0.30 0.48 0.31 0.00 0.00 0.00 3.38 4.47 C10 0.20 0.67 0.00 0.00 0.00 0.00 0.00 0.87 Sum 16.81 30.84 4.79 0.00 0.09 0.15 47.32 100 Embodiment 4 C5 11.66 23.45 0.96 0.00 0.13 0.16 0.00 36.36 C6 2.43 6.21 0.86 0.00 0.00 0.00 3.7 13.2 C7 0.21 2.45 1.43 0.00 0.00 0.00 14.77 18.86 C8 0.03 0.94 1.55 0.00 0.00 0.00 23.15 25.67 C9 0.10 0.23 0.43 0.00 0.00 0.00 4.89 5.65 C10 0.10 0.16 0.00 0.00 0.00 0.00 0.00 0.26 Sum 14.53 33.44 5.23 0.00 0.13 0.16 46.51 100 Table 8 Composition of Raw Materials (wt%) Components Embodiment 4 Iso-butane 56.52 N-butane 43.48 Date Recue/Date Received 2021-06-23

Claims (24)

CLAIMS:

1. A reaction-regeneration device for dehydrogenation of alkane, comprising:
a reactor;
a regenerator arranged above the reactor;
a spent catalyst riser pipe, being a straight pipe extending in an axial direction of the reactor; a first end of the spent catalyst riser pipe being located in the reactor; a second end of the spent catalyst riser pipe being in the regenerator from a top of the reactor;
wherein, the first end of the spent catalyst riser pipe is located in a lower part in the reactor;
a regenerated catalyst delivery pipe, being a straight pipe extending in the axial direction of the reactor; a first end of the regenerated catalyst delivery pipe being located in the regenerator;
a second end of the regenerated catalyst delivery pipe being in the reactor from a bottom of the regenerator; and a lifting medium pipe, a first end of the lifting medium pipe being arranged outside the reactor; and a second end of the lifting medium pipe being located inside the spent catalyst riser pipe.

2. The device of claim 1, wherein, the second end of the lifting medium pipe is located above the first end of the spent catalyst riser pipe.

3. The device of claim 1 or 2, wherein, a gas stripping medium distributor is arranged at the lower part of the reactor and is located above the first end of the spent catalyst riser pipe.

4. The device of claim 3, wherein, the gas stripping medium distributor is one or more pipes in an annular shape arranged on a same plane, and nozzles are arranged on the one or more pipes.

5. The device of claim 1 or 2, wherein, the first end of the spent catalyst riser pipe is close to the bottom of the reactor.

6. The device of any one of claims 1-5, wherein, the second end of the spent catalyst riser pipe is configured to be stuck into a dilute-phase section of the regenerator.

7. The device of any one of claims 1-5, wherein, the second end of the regenerated catalyst delivery pipe is located in the reactor and located below a settling section of the reactor.

8. A method for aromatization of propane and butane, comprising:
carrying out a catalytic dehydrogenation reaction of propane and butane under the action of a dehydrogenation catalyst to obtain a dehydrogenation reaction product;
and carrying out an aromatization reaction of the dehydrogenation reaction product under the action of a catalyst to obtain an aromatization product, wherein, in the catalytic dehydrogenation reaction, a temperature of the dehydrogenation reaction is in a range of 500 C to 660 C; and the catalytic dehydrogenation reaction of alkane is carried out in the reaction-regeneration device for dehydrogenation of alkane according to any one of claims 1-7.

9. The method of claim 8, wherein, a temperature of the aromatization reaction is in a range of 360 C to 440 C.

10. The method of claim 9, wherein, during the aromatization reaction, a pressure is in a range of 0.5 MPa to 1.0 MPa, and a mass space velocity is in a range of 0.8 V to 1.5 V.

11. The method of claim 8, wherein, an active component in the dehydrogenation catalyst comprises at least one element selected from the group consisting of In, Ge, Al, Bi, and Ru.

12. The method of claim 8, wherein, a preparation method of the dehydrogenation catalyst comprises: carrying out a reaction between a substance containing at least one element selected from the group consisting of In, Ge, Al, Bi, and Ru, and water, and then carrying out heating treatment to obtain the dehydrogenation catalyst.

13. The method of claim 12, wherein, the substance containing at least one element selected from the group consisting of In, Ge, Al, Bi, and Ru comprises an elementary substance, alloy, carbon oxide or nitrogen oxide.

14. The method of claim 13, wherein, the reaction between the substance containing at least one element selected from the group consisting of In, Ge, Al, Bi, and Ru and water is carried out at a temperature of 20 C to 900 C.

15. The method of claim 14, wherein, the reaction is carried out at a temperature in a range of 20 C to 300 C.

16. The method of claim 15, wherein, the reaction is carried out at a temperature in a range of 100 C to 200 C.

17. The method of claim 12, wherein, the substance containing at least one element selected from the group consisting of In, Ge, AI, Bi, and Ru is firstly soaked in acid liquor/alkaline liquor before reacting with water.

18. The method of claim 8, wherein, a preparation method of the dehydrogenation catalyst comprises: loading a substance containing at least one element selected from the group consisting of In, Ge, Al, Bi, and Ru on a canier; and then canying out heating treatment to obtain the dehydrogenation catalyst.

19. The method of claim 18, wherein, the substance containing at least one element selected from the group consisting of In, Ge, Al, Bi, and Ru comprise an elementary substance, alloy, carbon oxide, nitrogen oxide, nitrate, sulfate or chloride.

20. The method of claim 18, wherein, the carrier is selected from one or more of a zeolite, SiO2, MgO, ZnA1204, Zn(Gai_x)A1x04, Mg(Ga1-0A1.04, MgA1204, TiO2, Ga203, CeO2, and a hollow ceramic sphere; and the zeolite is selected from A zeolites, X
zeolites, Y zeolites, M
zeolites, ZSM zeolites, aluminum phosphate zeolites, HMS zeolites, SBA
zeolites, M41s zeolites, and isomorphous substitution of Al and Si zeolites by heteroatoms containing P
and Ti.

21. The method of claim 12 or 18, wherein, the heating treatment comprises drying and/or roasting, wherein, a drying temperature is in a range of 50 C to 300 C, and roasting temperature is in a range of 300 C to 1100 C.

22. The method of claim 12 or 18, comprising: adding an additive to reactants before reaction, or soaking the additive in a prepared catalyst, wherein, the additive comprises one or more elements selected from the group consisting of alkaline metals, alkaline earth metals, Ni, Cu, La, Y, Ce, Fe, and Zr.

23. The method of claim 22, wherein, an amount of the additive is in a range of 0% to 30%
of the reactants.

24. The method of claim 23, wherein, the amount of the additive is in a range of 0.005 wt%
to 10 wt%.