CN111068590A

CN111068590A - Solid acid alkylation method

Info

Publication number: CN111068590A
Application number: CN201811229732.2A
Authority: CN
Inventors: 胡立峰; 侯栓弟; 刘铮; 唐晓津; 毛俊义; 朱振兴; 张久顺; 赵志海; 李永祥
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2018-10-22
Filing date: 2018-10-22
Publication date: 2020-04-28
Anticipated expiration: 2038-10-22
Also published as: CN111068590B

Abstract

The invention relates to the field of solid acid alkylation, and discloses a solid acid alkylation method, which comprises the following steps: the method is carried out in a liquid-solid axial moving bed reaction and regeneration device, the liquid-solid axial moving bed reaction and regeneration device comprises an axial moving bed reactor, a spent catalyst receiver, a catalyst regenerator and a regenerant receiver which are sequentially connected, and a catalyst outlet of the regenerant receiver is communicated with a catalyst inlet of the axial moving bed reactor; the axial moving bed reactor is provided with at least two catalyst bed layers which are arranged up and down, and a feed inlet is arranged above each catalyst bed layer; liquid phase raw materials are fed into the axial moving bed reactor from a feed inlet arranged above each catalyst bed layer to be in contact reaction with the catalyst. The method provided by the invention can not only realize the continuous and stable operation of the solid acid alkylation reaction, but also improve the selectivity of the target product.

Description

Solid acid alkylation method

Technical Field

The invention relates to the field of solid acid alkylation, in particular to a solid acid alkylation method.

Background

At present, one of the most important tasks of the oil refining industry is to provide transportation fuel, and gasoline is widely used in transportation industry and other industries as an important transportation fuel. With the increase of gasoline consumption and the stricter environmental protection standards, it is a hot point for research and discussion to focus on how to solve the problem of clean gasoline production.

Under the action of strong acid, the technology of using isoparaffin (mainly isobutane) and olefin (C3-C5 olefin) as raw materials to generate alkylate provides possibility for clean production of gasoline. The alkylate oil has higher octane value and lower vapor pressure, mainly consists of saturated hydrocarbon, and does not contain substances such as sulfur, nitrogen, olefin, aromatic hydrocarbon and the like, so the alkylate oil is called clean gasoline and is an ideal blending component for aviation gasoline and motor gasoline. Alkylation techniques can be divided into liquid acid alkylation and solid acid alkylation in terms of catalyst form. At present, about 90% of the world's alkylation energy is provided by liquid acid alkylation technology (sulfuric acid process and hydrofluoric acid process), and although the liquid acid alkylation technology is mature and has better reaction selectivity, there are many problems, such as severe corrosion of equipment in the liquid acid alkylation process. In addition, for the sulfuric acid method, the acid consumption in the process is huge, a large amount of waste acid has certain potential safety hazards in transportation and treatment, and for the hydrofluoric acid method, hydrofluoric acid has strong corrosivity and toxicity and is easy to volatilize, so that great harm is caused to human bodies. Therefore, compared with the prior art, the solid acid is adopted as the catalyst, so that the environment is not polluted, the problem of equipment corrosion does not exist, the method can be regarded as a green alkylation process technology, and the method has a good development prospect. However, since the solid acid catalyst is easily deactivated during the solid acid alkylation process and frequent regeneration operation is required to maintain a certain reaction activity, it is very important to develop a reactor technology capable of continuously performing the reaction and regeneration process to promote the development of the solid acid alkylation technology.

US8373014 discloses a solid acid alkylation reaction process using an overlapping radial moving bed as reactor. In the method, a structure similar to a catalytic reforming overlapped radial moving bed is adopted, and a single-section reactor is internally provided with an annular barrel with the periphery playing a role in distributing reaction materials, a central pipe playing a role in collecting materials and a reaction bed layer area clamped between the annular barrel and the central pipe; and a catalyst material conveying pipe is adopted between the two sections of reactors to convey the catalyst in the upper section of the catalyst bed layer to the reaction bed layer area of the lower section of the reactor. The effluent material in the middle reactor is divided into two parts, one part is pumped back to the upstream reactor and is mixed with fresh raw materials by the mixer to be used as the feeding material of the upstream reactor, and the part can be called as recycling material; the other part is mixed with fresh raw materials before being introduced into a feed mixer of the downstream reactor and then used as the feed of the downstream reactor, and the part is directly used without pump pressurization. In addition, the recycle stream portion also needs to be passed through a heat exchanger to extract the heat of reaction.

CN1879956A discloses a fluidized bed solid acid alkylation technology, which mainly comprises a riser reactor, a fluidized bed reactor, a loop regenerator and a moving bed regenerator. Wherein the liquid velocity range in the riser reactor is 0.1-3 m/s, and the liquid velocity range in the fluidized bed reactor is 0.26-7.68 cm/s. The regeneration process may determine the form of the regeneration reactor according to the regeneration time, and if the regeneration time is several seconds to several tens of seconds, a loop regenerator alone may be used. If the regeneration time is dozens of seconds to dozens of minutes, a moving bed regenerator can be independently adopted, and the liquid velocity of the regeneration liquid is 0.2-3 cm/s.

CN1113906A discloses a fluidized bed solid acid aromatic alkylation process technology, which mainly comprises a liquid-solid ascending reactor, a spent catalyst settling and backwashing tower, a liquid-solid parallel flow ascending regenerator and a regenerated catalyst settling and backwashing tower. The particle size of the catalyst is required to be 0.05-0.8 mm, the liquid velocity of the liquid which can carry the catalyst to flow upwards in the reactor and the regenerator is 1-15 times of the settling velocity of the particle terminal, the catalyst is washed and regenerated by adopting the washing liquid flowing from bottom to top in the settling and backwashing tower, and the flow velocity of the washing liquid is 0.5-5 times of the settling velocity of the particle terminal.

In order to realize continuous and stable operation of a reaction device, at least more than two reactors are required for switching operation of a fixed bed alkylation technology and a fluidized bed alkylation technology disclosed in the prior art, a catalyst in a bed layer is subjected to high-temperature regeneration at intervals, and a high-temperature bed layer is subjected to cooling operation after deep regeneration. In addition, in the prior art, the catalyst in the solid acid alkylation reaction device is difficult to maintain stable and high target product selectivity.

Disclosure of Invention

The invention provides a solid acid alkylation method, aiming at solving the problems that the solid acid alkylation reaction in the prior art can not continuously and stably operate and the selectivity of a target product needs to be further improved. The method provided by the invention can not only realize the continuous and stable operation of the solid acid alkylation reaction, but also improve the selectivity of the target product.

In order to achieve the above object, a first aspect of the present invention provides a solid acid alkylation method comprising:

the method is carried out in a liquid-solid axial moving bed reaction and regeneration device, wherein the liquid-solid axial moving bed reaction and regeneration device comprises an axial moving bed reactor, a spent catalyst receiver, a catalyst regenerator and a regenerant receiver which are sequentially connected, wherein a catalyst outlet of the regenerant receiver is communicated with a catalyst inlet of the axial moving bed reactor; the axial moving bed reactor is provided with at least two catalyst bed layers which are arranged up and down, and a feed inlet is arranged above each catalyst bed layer;

a catalyst conveying pipe is arranged between every two adjacent catalyst bed layers, so that the catalyst can move from top to bottom in the axial moving bed reactor;

liquid phase raw materials are fed into the axial moving bed reactor from a feed inlet arranged above each catalyst bed layer to be in contact reaction with the catalyst.

Preferably, a reaction material baffle is arranged between two adjacent catalyst bed layers and used for enhancing the mixing of the reacted material and the liquid fresh raw material fed from the feeding port.

Preferably, a catalyst distribution piece is arranged between two adjacent catalyst beds and used for dispersing the catalyst at the outlet of the catalyst conveying pipe.

The solid acid alkylation method provided by the invention has the following advantages:

1) compared with the fixed bed alkylation technology, the continuous and stable operation of the reaction device can be realized only by using one reactor;

2) compared with the fluidized bed alkylation technology, the method provided by the invention can realize the service life distribution of the catalyst, and can remove the deactivated catalyst out of the system and then supplement the catalyst with fresh catalyst; the fluidized bed reactor cannot realize the service life distribution of the catalyst;

3) the method provided by the invention uses an axial moving bed reactor, and can meet the requirements of a single set of equipment, thereby reducing the investment cost of the device, and in addition, by leading the inactivated catalyst particles out of the reactor for deep regeneration, the continuous operation of the catalyst reaction and regeneration is realized on the premise of not influencing the stable operation of the reaction device, the stable balance activity of the catalyst in the device is maintained, and the selectivity of the target product in the alkylate oil is improved.

Drawings

FIG. 1 is a liquid-solid axial moving bed reaction and regeneration apparatus according to one embodiment of the present invention;

FIG. 2 is a schematic view of a baffle according to the present invention;

FIG. 3 is a liquid-solid axial moving bed reaction and regeneration apparatus according to an embodiment of the present invention.

Description of the reference numerals

1-axial moving bed reactor 2-feed inlet 3-catalyst bed layer

4-catalyst regenerator 5-spent agent receiver 6-regenerant receiver

7-fluid removal filter 8-regenerated medium filter 10-separating element

11-reaction Material baffle 111-Main shaft 112-conveying Member

113-baffle 12-conical distribution baffle 13-horizontal distribution baffle

15-liquid-withdrawing material outlet 16-catalyst conveying pipe 17-pipeline

19-first branch line 20-second branch line 21-third branch line

25-first particle flow regulator 30-regenerated medium inlet 31-regenerated medium outlet

32-liquid phase feed make-up inlet 33-second particle flow regulator 37-bottom catalyst collection zone

38-catalyst buffer tank

Detailed Description

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

In the present invention, the use of directional terms such as "upper" and "lower" generally means upper and lower as generally described with reference to the drawings, unless otherwise specified. Use of the terms of orientation such as "inner and outer" refer to inner and outer relative to the profile of the respective component itself.

In a first aspect, the present invention provides a solid acid alkylation process comprising: the method is carried out in a liquid-solid axial moving bed reaction and regeneration device, the liquid-solid axial moving bed reaction and regeneration device comprises an axial moving bed reactor 1, a spent catalyst receiver 5, a catalyst regenerator 4 and a regenerant receiver 6 which are sequentially connected, wherein a catalyst outlet of the regenerant receiver 6 is communicated with a catalyst inlet of the axial moving bed reactor 1; the axial moving bed reactor 1 is provided with at least two catalyst bed layers 3 which are arranged up and down, and a feed inlet 2 is arranged above each catalyst bed layer 3 of the axial moving bed reactor 1; a catalyst conveying pipe 16 is arranged between every two adjacent catalyst bed layers 3, so that the catalyst can move from top to bottom in the axial moving bed reactor 1;

liquid phase raw materials are fed into the axial moving bed reactor 1 from a feed inlet arranged above each catalyst bed layer 3 to be in contact reaction with the catalyst.

In the present invention, the sequential connection means that the catalyst outlet of the axial moving bed reactor 1 is connected to the catalyst inlet of the spent catalyst receiver 5, the catalyst outlet of the spent catalyst receiver 5 is connected to the catalyst inlet of the catalyst regenerator 4, and the catalyst outlet of the catalyst regenerator 4 is connected to the catalyst inlet of the regenerant receiver 6. The catalyst outlet of the regenerant receiver 6 communicates with the catalyst inlet of the axial moving bed reactor 1 to feed the regenerated catalyst into the axial moving bed reactor 1.

The axial moving bed reactor refers to a moving bed reactor with the moving direction of a catalyst being axial.

According to the method provided by the invention, the axial moving bed reactor 1 is provided with at least two catalyst bed layers which are arranged up and down, and preferably 3-8 catalyst bed layers 3 which are arranged up and down. The thickness of the catalyst bed 3 is not particularly limited in the present invention, and preferably, the thickness of each catalyst bed 3 is each independently 10 to 30% of the height of the axial moving bed reactor 1.

In the embodiment of the present invention, the height of the axial moving bed reactor 1 is 15m and the inner diameter is 600mm, but the present invention is not limited thereto. Those skilled in the art can make appropriate adjustments according to actual conditions.

The liquid phase feedstock of the present invention may be any of various feedstocks conventionally used in the art capable of conducting solid acid alkylation reactions. For example, the liquid phase feed contains isoparaffins and olefins. The isoparaffin may be an isoparaffin commonly used in alkylation reactions, preferably C₄-C₆More preferably isobutane. The olefin is preferably a mono-olefin, more preferably C₃-C₆More preferably C₄A mono-olefin.

According to the solid acid alkylation process of the present invention, the isoparaffins and olefins of the feed to each catalyst bed may be conventionally selected. Preferably, the molar ratio of isoparaffin to olefin (i.e., the alkane to olefin ratio) of the feed entering each catalyst bed is 200-: 1. this allows not only complete or substantially complete conversion of the olefin but also higher product selectivity and higher activity stability of the alkylation catalyst. Preferably, the feed to each catalyst bed has a molar ratio of isoparaffin to olefin of 400-750.

According to the present invention, the reaction temperature in the axial moving bed reactor is preferably carried out at a temperature lower than the critical temperature of isoparaffin, more preferably not higher than 120 deg.C (e.g., 30 to 120 deg.C), still more preferably not higher than 100 deg.C, still more preferably 30 to 100 deg.C, e.g., 60 to 80 deg.C. The pressure in the alkylation reaction conditions may generally be in the range 1 to 3.4MPa, preferably 1.2 to 3.2MPa, such as 1.5 to 3.0 MPa. The pressure is a gauge pressure.

According to the invention, the mass space velocity of the material entering each catalyst bed layer calculated by olefin can be 0.05-1h^-1Preferably 0.07-0.5h^-1For example, 0.08 to 0.25h^-1。

According to a preferred embodiment of the present invention, the residence time of the catalyst in the axially moving bed reactor is in the range from 6 to 72h, preferably from 12 to 72 h.

The catalyst used in the method of the present invention is not particularly limited, and may be any of various catalysts conventionally used in the art, for example, a solid acid catalyst.

Preferably, the solid acid catalyst contains a molecular sieve and a refractory inorganic oxide, and the content of the molecular sieve is 65 to 95% by weight, more preferably 65 to 90% by weight, and the content of the refractory inorganic oxide is 5 to 35% by weight, more preferably 10 to 35% by weight, based on the total amount of the solid acid catalyst.

Further preferably, the molecular sieve is at least one selected from FAU structure zeolite, BETA structure zeolite and MFI structure zeolite.

In the present invention, the heat-resistant inorganic oxide means an inorganic oxide having a maximum use temperature of not less than 600 ℃. The refractory inorganic oxide may be alumina and/or silica.

In a more preferred embodiment of the present invention, the solid acid catalyst further comprises a metal active component selected from at least one of Fe, Co, Ni, Pd and Pt, and the content of the metal active component is 0.15 to 2 wt% based on the total amount of the solid acid catalyst. With the catalyst according to this preferred embodiment, longer cycle life and service life can be achieved, while still achieving higher product selectivity, all the other conditions being the same.

According to the invention, the average particle size of the catalyst may be 0.3 to 3 mm.

According to a preferred embodiment of the present invention, a separating member 10 is disposed between two adjacent catalyst beds 3, the separating member 10 is communicated with a catalyst conveying pipe 16, the separating member 10 is used for separating materials and catalysts after reaction of the upstream catalyst bed, and the catalysts separated by the separating member 10 move downwards through the catalyst conveying pipe 16. The reacted material and catalyst in the upstream catalyst bed are separated by the separating part 10 to obtain the reacted material and catalyst, the catalyst moves downwards through the catalyst conveying pipe 16, and the reacted material is mixed with the liquid fresh material fed from the feeding port above the catalyst bed 3 in the space between two adjacent catalyst beds (referred to as the bed space before the reaction bed in the invention) and then flows into the downstream catalyst bed.

According to an embodiment of the present invention, the separating member 10 may be a screen having holes (the hole diameter may be determined according to the size of the catalyst particles) for allowing the reacted material to pass through, so as to separate the reacted material from the catalyst.

In order to mix the reacted material and the liquid fresh material flowing into the downstream catalyst bed layer more uniformly, a reaction material baffle 11 is preferably arranged between two adjacent catalyst bed layers 3, and the reaction material baffle 11 is used for enhancing the mixing of the reacted material and the liquid fresh material fed from the feed inlet 2.

The present invention is not particularly limited to the specific structure of the reaction material baffle 11, as long as it can enhance the mixing of the reacted material and the liquid fresh raw material. In particular, the reaction material baffles 11 are placed in the space of the bed layer in front of the reaction bed layer, and the number of the baffles can be 1 or more than two, and preferably 1-6.

According to a first preferred embodiment of the invention, as shown in fig. 2, the reaction material baffle 11 comprises a main shaft 111 and a conveying member 112 extending helically in the axial direction of the main shaft. Specifically, the inlet of the spirally extending flow channel formed by the conveying member 112 is set according to the position of the feed port 2 so that the reacted material and the liquid fresh raw material flow from the spirally extending flow channel formed by the conveying member 112, thereby achieving mixing.

According to a second preferred embodiment of the present invention, as shown in fig. 1, the reaction material baffle 11 comprises a plurality of baffles 113, the plurality of baffles 113 are arranged obliquely in the axial direction of the axial moving-bed reactor 1, and the plurality of baffles 113 are arranged alternately with each other to form flow passages through which the reaction material can pass. The plurality of baffles 113 may be disposed obliquely downward or obliquely upward in the axial direction of the axial moving-bed reactor 1 (as shown in fig. 1). Preferably, the baffle 113 extends at an angle of 5-60 °, more preferably 10-40 ° to the horizontal.

The baffles 113 are arranged in a staggered manner in the invention, which means that no closed area is formed between the baffles 113, so that the reaction materials can smoothly flow downwards. According to one embodiment of the present invention, as shown in fig. 1, a part of the baffles 113 is fixedly connected to the wall of the axially moving bed reactor 1, a part of the baffles 113 is fixedly connected to the wall of the catalyst transport pipe 16, and the baffles 113 are arranged in parallel with each other. Preferably, the distance between adjacent baffles 113 is 15-60 mm.

According to a preferred embodiment of the present invention, a catalyst distribution member is disposed between two adjacent catalyst beds 3, and the catalyst distribution member is used for distributing the catalyst at the outlet of the catalyst conveying pipe 16. If no catalyst distribution member is provided, the catalyst at the outlet of the catalyst transfer pipe 16 is liable to form a conical pile in the downstream catalyst bed. Preferably, the catalyst distribution member comprises a conical distribution baffle 12, and the conical distribution baffle 12 is coaxially arranged with the catalyst conveying pipe 16. The catalyst at the outlet of the catalyst conveying pipe 16 falls on the tip of the conical distribution baffle 12 under the action of gravity, and is dispersed to the two horizontal sides of the catalyst conveying pipe 16 through the dispersion action of the conical distribution baffle 12. It is further preferred that the number of the conical distribution baffles 12 and the number of the catalyst conveying pipes 16 are the same.

According to a preferred embodiment of the present invention, the catalyst distribution member further comprises a horizontal distribution baffle 13 disposed below the conical distribution baffle 12, and the horizontal distribution baffle 13 is provided with holes for catalyst to pass through. In the present invention, the number of the horizontal distribution baffles 13 is not particularly limited, and may be 1, or two or more, and it is preferable that each horizontal distribution baffle is provided at a radially intermediate position (and an axially lower position) of each of two adjacent conical distribution baffles 12. The radial and axial directions refer to the radial and axial directions of the axial moving-bed reactor 1.

Further preferably, the holes of the horizontal distribution baffle 13 become gradually larger in a horizontal outward direction along the center of the axial moving bed reactor 1. With this preferred embodiment, the part of the catalyst that is dispersed near the center of the axial moving bed reactor 1 and passes through the tapered distribution baffle 12 passes through the holes of the horizontal distribution baffle 13, and the part of the catalyst that cannot pass through is dispersed to the edge of the axial moving bed reactor 1, which is more beneficial to ensuring the uniform dispersion of the catalyst.

Further preferably, the horizontal distribution baffle 13 may be a circular distribution plate with a low open area in the middle area and a high open area in the side walls.

The catalyst in each catalyst bed layer of the axial moving bed reactor 1 is gradually deactivated along with the reaction, and simultaneously gradually falls to the catalyst bed layer further downstream, finally reaches the bottom of the axial moving bed reactor 1, and then is conveyed to a spent catalyst receiver 5 through a catalyst conveying pipeline.

According to a preferred embodiment of the present invention, the axially moving bed reactor 1 is provided with a bottom catalyst collection zone 37 at its lower part. The catalyst passing through the most downstream catalyst bed is delivered to the bottom catalyst collection zone 37, and a certain amount of catalyst is collected and delivered to the spent catalyst receiver 5.

According to an embodiment of the present invention, as shown in fig. 1, material pipeline valves between the containers are respectively disposed on communicating pipelines of the axial moving bed reactor 1 and the spent agent receiver 5, the spent agent receiver 5 and the catalyst regenerator 4, the catalyst regenerator 4 and the regenerant receiver 6, and the regenerant receiver 6 and the axial moving bed reactor 1.

According to a preferred embodiment of the invention, the spent agent receiver 5 (preferably the bottom) is provided with a spent liquor outlet 15. The invention can remove the liquid phase materials carried in the catalyst in the spent catalyst receiver 5 by directly reducing the pressure or introducing high-pressure hydrogen, nitrogen and other pressurizing modes, and the liquid phase materials can be output through the liquid phase material outlet 15. Preferably, a liquid removing filter 7 is arranged on the liquid-returning material conveying line which is sent out from the liquid-returning material outlet 15. The liquid removal filter 7 is used for blocking fine catalyst powder or fine particles.

The catalyst after the liquid removal in the spent catalyst receiver 5 is sent to the catalyst regenerator 4 for regeneration. The catalyst regenerator 4 is provided with a regeneration medium inlet 30 and a regenerated medium outlet 31. The regeneration medium is fed into the catalyst regenerator 4 through the regeneration medium feed inlet 30 to contact with the catalyst to regenerate (preferably completely regenerate) the catalyst, and the regenerated medium is discharged through the regenerated medium discharge outlet 31. Preferably, a regenerated media filter 8 is provided on the regenerated media delivery line that is sent from the regenerated media outlet 31. The filter is used for blocking the catalyst of the regenerator from flowing into a gas circulation pressurization device at the downstream and collecting fine powder or fine particles generated by friction or purging in the regeneration process.

The method of the present invention is not particularly limited in the manner of regeneration, and may be carried out under conventional regeneration conditions. The regeneration medium may be an oxygen-containing atmosphere or a hydrogen-containing atmosphere. Specifically, the regeneration may be performed in a hydrogen-containing atmosphere, or may be performed in an oxygen-containing atmosphere. The oxygen-containing atmosphere contains oxygen and optionally a carrier gas, which may be selected from the group consisting of inactive gases, specific examples of which may include, but are not limited to, nitrogen and group zero gases (e.g., argon). The oxygen-containing atmosphere may contain oxygen in an amount of 0.5 to 20 vol%. In addition, the oxygen content may be adjusted according to the progress of regeneration. The hydrogen-containing atmosphere may contain hydrogen and liquefied C4 gas, and the hydrogen content is 70-99 vol%.

As an example of regeneration, the regeneration is carried out in a hydrogen atmosphere, and the regeneration can be carried out at a temperature of 100-400 ℃, preferably 180-280 ℃; in the regeneration, the pressure in the reactor may be 0.1 to 5MPa, preferably 0.5 to 3.5MPa, and the pressure is a gauge pressure. As another example of regeneration, the regeneration is carried out in an oxygen-containing atmosphere, and the regeneration may be carried out at a temperature of 180 ℃.; during regeneration, the pressure in the reactor can be 0.01-0.5MPa, and the pressure is gauge pressure.

According to the present invention, the superficial flow velocity of the regeneration medium in the catalyst regenerator 4 is preferably in the range of 0.003 to 0.8m/s, more preferably in the range of 0.02 to 0.5 m/s.

According to a preferred embodiment of the invention, the method further comprises: fresh catalyst is introduced into the catalyst regenerator 4. Specifically, the catalyst regenerator 4 may be provided with a fresh catalyst feed for fresh catalyst to enter the catalyst regenerator 4. By providing a fresh catalyst feed port in the catalyst regenerator 4, a catalyst partially deactivated or a catalyst that is difficult to recover the initial activity can be replaced with a fresh catalyst, ensuring the treatment capacity of the apparatus. Specifically, a pump is provided on the fresh catalyst delivery line in communication with the fresh catalyst feed inlet.

The regenerated catalyst will flow through the catalyst transfer line at the bottom of the catalyst regenerator 4 into the regenerant receiver 6.

According to a preferred embodiment of the present invention, the method further comprises replacing the gas in the catalyst space in the regenerant receiver 6 with a liquid phase. Specifically, the regenerant receiver 6 is provided with a liquid phase feed makeup inlet 32. Gas in the liquid phase replacing catalyst interstice is introduced into the regenerant receiver 6 through the liquid phase make-up inlet 32. The liquid phase feed is not particularly limited in the present invention, and may be, for example, an alkane or a reaction product obtained from the bottom of the axial moving bed reactor 1.

The regenerated catalyst returns to the axial moving bed reactor 1 through a catalyst conveying pipeline between the regenerant receiver 6 and the axial moving bed reactor 1, continuously participates in the reaction until the catalyst is deactivated and then is conveyed to the spent catalyst receiver 5, and the catalyst circulates according to the flow.

According to a preferred embodiment of the invention, the spent catalyst receiver 5, the catalyst regenerator 4 and the regenerant receiver 6 are sequentially arranged from top to bottom, and catalyst flow lines among the spent catalyst receiver 5, the catalyst regenerator 4 and the regenerant receiver 6 are vertically arranged or obliquely arranged at an included angle of not less than 40 degrees with the horizontal plane. By adopting the preferred embodiment, the catalyst granules can smoothly flow from top to bottom, and the material is prevented from being accumulated or remaining in a pipeline to influence the valve tightness or the catalyst regeneration effect.

According to a preferred embodiment of the present invention, a first particle flow regulator 25 is disposed on a communicating line between a catalyst outlet of the axial moving bed reactor 1 and a catalyst inlet of the spent catalyst receiver 5; a second particle flow regulator 33 is provided on a communicating line of the catalyst outlet of the regenerant receiver 6 and the catalyst inlet of the axial moving bed reactor 1. The first particle flow rate adjuster 25 and the second particle flow rate adjuster 33 are not particularly limited in the present invention as long as the flow rate of the catalyst particles can be adjusted. Further preferably, the first particle flow regulator 25 and the second particle flow regulator 33 are each independently an L-shaped or approximately L-shaped material delivery valve group. Specifically, the L-shaped or approximately L-shaped material conveying valve group is also communicated with at least one liquid phase material feeding pipeline. The flow resistance of the granular materials can be increased by arranging the granular flow regulator, and meanwhile, the regulator is communicated with at least one liquid-phase material feeding pipeline for increasing the flow driving force of the granular materials and reducing the flow resistance of the granular materials. The L-shaped or approximately L-shaped material conveying valve group is arranged, and the discharge rate of the catalyst can be adjusted by changing the flow of the liquid-phase material entering the valve group, so that the falling rate and the retention time of the catalyst in each reaction bed layer in the reactor can be controlled and adjusted.

According to a preferred embodiment of the invention, the device further comprises a catalyst buffer tank 38, the catalyst buffer tank 38 is arranged between the axial moving bed reactor 1 and the spent agent receiver 5, a catalyst inlet of the catalyst buffer tank 38 is communicated with a catalyst outlet of the axial moving bed reactor 1, and a catalyst outlet of the catalyst buffer tank 38 is communicated with a catalyst inlet of the spent agent receiver 5. The catalyst buffer tank 38 is used for storing the catalyst discharged from the axial moving bed reactor 1 during the period of discharging the spent catalyst receiver from the liquid phase material and the catalyst to the catalyst regenerant, and ensures the continuity of the catalyst material flow in the axial moving bed reactor 1 and the smoothness of the device operation.

The method provided by the invention adopts a liquid-solid axial moving bed reaction and regeneration device, can realize continuous and stable operation of solid acid alkylation reaction and deactivated catalyst regeneration, improves the selectivity of target products and the flexibility of device operation, greatly reduces the investment cost of the catalyst, and improves the economic competitiveness of the device.

One embodiment of the solid acid alkylation process provided by the present invention is described below.

As shown in fig. 1, three catalyst beds 3 are arranged in an axial moving bed reactor 1, a spent catalyst receiver 5, a catalyst regenerator 4 and a regenerant receiver 6 are sequentially arranged from top to bottom, and catalyst flow pipelines among the three are vertically arranged. The fresh olefin raw material containing isobutane is introduced from a pipeline 17, mixed with a circulating material through a first branch pipeline 19, enters a reaction zone of the axial moving bed reactor 1 from the feeding hole 2 to be in contact reaction with the first catalyst bed layer 3, and is fed from the feeding hole 2 through a second branch pipeline 20 and a third branch pipeline 21 to be in contact reaction with a reacted material of an upstream catalyst bed layer to be mixed in a bed layer space in front of the reaction bed layer of the axial moving bed reactor 1. A separating piece 10 is arranged between two adjacent catalyst bed layers 3, the reacted materials pass through the separating piece 10, and the catalyst which does not pass through the separating piece 10 moves downwards through a catalyst conveying pipe 16. A reaction material baffle 11 is arranged between two adjacent catalyst bed layers 3, and the reaction material and the fresh material flow passing through the separating piece 10 are intensively mixed under the action of the reaction material baffle 11. And a catalyst distribution piece (comprising a conical distribution baffle 12 and a horizontal distribution baffle 13, wherein the conical distribution baffle 12 is coaxial with the catalyst conveying pipe 16, and the horizontal distribution baffle 13 is arranged below the conical distribution baffle 12) is also arranged between every two adjacent catalyst beds 3, and the catalyst at the outlet of the catalyst conveying pipe 16 is dispersed and falls to the downstream catalyst beds 3 under the action of the catalyst distribution piece. The lower part of the axially moving bed reactor 1 is provided with a bottom catalyst collecting zone 37. The catalyst passing through the most downstream catalyst bed is delivered to the bottom catalyst collection zone 37, and a certain amount of catalyst is collected and delivered to the spent catalyst receiver 5. A first particle flow regulator 25 is arranged on a communicating pipeline of the catalyst outlet of the axial moving bed reactor 1 and the catalyst inlet of the spent catalyst receiver 5 so as to regulate the flow of the catalyst particles. A liquid-phase material outlet 15 is arranged at the bottom of the spent agent receiver 5, liquid-phase materials carried in the catalyst are removed from the spent agent receiver 5, and a liquid-removing filter 7 is arranged on a liquid-phase material conveying pipeline sent out from the liquid-phase material outlet 15 to block fine catalyst powder or fine particles. The catalyst after liquid removal in the spent catalyst receiver 5 is sent to a catalyst regenerator 4 for regeneration, and the catalyst regenerator 4 is provided with a regeneration medium feeding port 30 and a regeneration medium discharging port 31. The regenerated medium is fed into the catalyst regenerator 4 through the regenerated medium feed inlet 30 to contact with the catalyst for regenerating the catalyst, and the regenerated medium is discharged through the regenerated medium discharge outlet 31. A regenerated medium filter 8 is disposed on the regenerated medium delivery line fed out from the regenerated medium outlet 31 to block fine powder or fine particles. The catalyst regenerator 4 may also be provided with a fresh catalyst inlet for fresh catalyst to enter the catalyst regenerator 4. By providing a fresh catalyst feed port in the catalyst regenerator 4, a catalyst partially deactivated or a catalyst that is difficult to recover the initial activity can be replaced with a fresh catalyst, ensuring the treatment capacity of the apparatus. The regenerated catalyst flows into the regenerant receiver 6 through a catalyst transfer line at the bottom of the catalyst regenerator 4, and the regenerant receiver 6 is provided with a liquid phase feed make-up inlet 32. Gas in the liquid phase replacing catalyst interstice is introduced into the regenerant receiver 6 through the liquid phase make-up inlet 32.

The regenerated catalyst returns to the axial moving bed reactor 1 through a catalyst conveying pipeline between the regenerant receiver 6 and the axial moving bed reactor 1 to continuously participate in the reaction until the catalyst is deactivated and then conveyed to the spent catalyst receiver 5, and the catalyst circulates according to the process. A second particle flow regulator 33 is provided on a communicating line of the catalyst outlet of the regenerant receiver 6 and the catalyst inlet of the axial moving bed reactor 1 to regulate the catalyst particle flow.

The present invention will be described in detail below by way of examples.

Example 1

This example was carried out on a liquid-solid axial moving bed reaction and regeneration apparatus as shown in FIG. 1. Wherein, the axial moving bed reactor 1, the spent catalyst receiver 5, the catalyst regenerator 4 and the regenerant receiver 6 are connected in sequence through pipelines.

The inner diameter of the axial moving bed reactor 1 is 600mm, the height is 15m, the height of each section of catalyst bed 3 (respectively marked as a first catalyst bed, a second catalyst bed and a third catalyst bed) which is provided with three catalyst beds 3 from top to bottom is 3.5m, and the distance between adjacent catalyst beds 3 is 1.2 m. 2 cylindrical catalyst conveying pipes 16 are respectively arranged between the first catalyst bed layer and the second catalyst bed layer and between the second catalyst bed layer and the third catalyst bed layer, and the inner diameter of each catalyst conveying pipe 16 is 20 mm. Separating pieces 10 (wedge-shaped filter screens with the gap width of 0.2 mm) are respectively arranged below the first catalyst bed layer and the second catalyst bed layer. 1 reaction material baffle 11 shown in fig. 2 is respectively arranged between the first catalyst bed layer and the second catalyst bed layer and between the second catalyst bed layer and the third catalyst bed layer, the reaction material baffle 11 comprises a main shaft 111 and a conveying part 112 spirally extending along the axial direction of the main shaft, and the inlet of a spirally extending flow channel formed by the conveying part 112 is positioned below the feed inlets 2 of the fresh olefin raw materials of the second branch pipeline 20 and the third branch pipeline 21. Reactant flow baffles 11 are disposed in the annular space between the central region of catalyst transfer tube 16 and the reactor wall.

Still be provided with 3 among first catalyst bed, the second catalyst bed and between second catalyst bed, the third catalyst bed respectively and taper distribution baffle 12 (highly being 0.1m) with the coaxial setting of catalyst conveyer pipe 16, 3 sets up horizontal distribution baffle 13 (circular distribution board) of taper distribution baffle 12 below is provided with the hole that supplies the catalyst to pass through on the horizontal distribution baffle 13, along axial moving bed reactor 1's central level to the outside direction, the hole on the horizontal distribution baffle 13 progressively enlarges, and the biggest hole aperture sets up to 25mm, and the minimum hole aperture sets up to 5 mm. The lower part of the axially moving bed reactor 1 is provided with a bottom catalyst collecting zone 37.

The spent catalyst receiver 5, the catalyst regenerator 4 and the regenerant receiver 6 are sequentially arranged from top to bottom, and catalyst flow pipelines among the spent catalyst receiver 5, the catalyst regenerator 4 and the regenerant receiver 6 are vertically arranged. The diameter of the spent catalyst receiver 5, the diameter of the catalyst regenerator 4 and the diameter of the regenerant receiver 6 are all 1200mm, and the height of each straight pipe section is 6 m. The diameter of the material circulation line was 250 mm.

After the mixture of reaction fresh raw materials of isobutane, normal butane, butylene and the like is fed from a fresh material feeding pipeline 17, the reaction fresh raw materials are divided into three paths to enter the corresponding catalyst bed layers 3, and the molar ratio of alkane to alkene of the mixed material entering each catalyst bed layer 3 is 700: 1, the flow rate of the recycled material in the reactor was 1.9m/s, the corresponding total fresh feed rate was 482kg/h, and the olefin mass space velocity was 0.25h^-1. The residence time of the catalyst in the axially moving bed reactor 1 was 72 h. The catalyst used is a molecular sieve spherical catalyst with FAU structure, and the average particle size is 1.8 mm. The preparation method comprises the steps of removing sodium ions on a NaY type molecular sieve with an FAU structure produced by China petrochemical catalyst division through steps of ion exchange and the like; the molecular sieve was then mixed with alumina in a ratio of 65: 35, mixing uniformly, preparing into small balls by adopting an oil ammonia column forming method, and further drying and roasting to prepare the catalyst. The reaction temperature in the axial moving bed reactor 1 was 70 ℃ and the reaction pressure was 2.5 MPa.

Fresh materials and circulating materials are mixed and fed into the axial moving bed reactor 1 from the feeding hole 2 to be in contact reaction with the catalyst filled in the first catalyst bed layer, the reacted materials obtained by separation of the separating piece 10 and the fresh materials from the first branch pipeline 19 are fed into the second catalyst bed layer to be reacted through reinforced mixing of the baffle piece 11, the catalyst obtained by separation of the separating piece 10 dispersedly falls to the downstream catalyst bed layer under the action of the catalyst distributing piece through the catalyst conveying pipe 16, and finally the catalyst falls to the catalyst collecting region 37 at the bottom. The catalyst obtained from the bottom catalyst collecting zone 37 is sent to the spent catalyst receiver 5 through the catalyst outlet. A first particle flow regulator 25 (an L-shaped material conveying valve group) is arranged on a communicating pipeline between a catalyst outlet of the axial moving bed reactor 1 and a catalyst inlet of the spent catalyst receiver 5, and the L-shaped material conveying valve group is also communicated with a liquid-phase material feeding pipeline to control the flow (20kg/h) of the catalyst. And introducing nitrogen into the spent catalyst receiver 5 to remove liquid-phase materials carried in the catalyst, outputting the liquid-phase materials through a liquid-withdrawing material outlet 15, and arranging a liquid-removing filter 7 on a liquid-withdrawing material conveying pipeline sent out from the liquid-withdrawing material outlet 15. The catalyst after liquid removal in the spent catalyst receiver 5 is sent into a catalyst regenerator 4 for regeneration, a mixed gas of nitrogen and air (the volume concentration of oxygen is 1-21 vol% and is adjusted from small to large, the apparent gas velocity is 0.1m/s) is used as a high-temperature deep regeneration medium of the catalyst, the period of high-temperature (350-. The catalyst regenerator 4 may also be provided with a fresh catalyst inlet for fresh catalyst to enter the catalyst regenerator 4.

The regenerated catalyst will flow through the catalyst transfer line at the bottom of the catalyst regenerator 4 into the regenerant receiver 6. The regenerant receiver 6 is provided with a liquid phase material supplement inlet 32, gas in the catalyst gap is replaced by the reacted oil-containing liquid phase material introduced into the regenerant receiver 6 through the liquid phase material supplement inlet 32, and the obtained catalyst slurry is circulated to the top of the axial moving bed reactor 1. A second particle flow regulator 33 (an L-shaped material conveying valve group) is arranged on a communicating pipeline between a catalyst outlet of the regenerant receiver 6 and a catalyst inlet of the axial moving bed reactor 1, and the L-shaped material conveying valve group is also communicated with a liquid-phase material feeding pipeline to control the flow (20kg/h) of the catalyst slurry.

Example 2

The solid acid alkylation reaction was carried out on the apparatus shown in FIG. 3. The difference from the example 1 is only that the device is also provided with a catalyst material buffer tank 38 with the diameter of 500mm and the height of a straight pipe section of 4.2m between the axial moving bed reactor 1 and the spent catalyst receiver 5.

The catalyst material buffer tank 38 is added in this embodiment, so that when the spent catalyst receiver performs the liquid removal operation and transfers the catalyst into the regenerator, the catalyst in the reactor still keeps moving downwards slowly at the original speed, and after the operation is completed, the catalyst accumulated in the catalyst buffer tank is gradually discharged to the spent catalyst receiver, so that the continuity of the catalyst material flow in the axial moving bed reactor 1 and the stability of the device operation are ensured.

Example 3

The solid acid alkylation reaction was carried out on the apparatus shown in FIG. 1. The difference is that the reaction material baffle 11 shown in fig. 2 is replaced by the reaction material baffle 11 shown in fig. 1, the reaction material baffle 11 comprises 8 parallel baffle plates 113 which are arranged in a staggered manner, the included angle between the extension direction of the baffle plates 113 and the horizontal plane is 25 degrees, the baffle plates 113 are arranged upwards along the axial inclination of the axial moving bed reactor 1, 4 baffle plates 113 are fixedly connected to the wall of the axial moving bed reactor 1, 4 baffle plates 113 are fixedly connected to the tube wall of the catalyst conveying tube 16, and the distance between the adjacent baffle plates 113 is 25 mm.

Comparative example 1

The solid acid alkylation reaction is carried out on two fixed bed medium-sized test devices connected in parallel, the specific operation process is that when a first reactor is in alkylation reaction, a second reactor carries out high-temperature deep regeneration operation, and the two fixed bed reactors connected in parallel are switched for use, so that the device can continuously and stably operate. Each fixed bed reactor had an internal diameter of 200mm and a height of 2500 mm. The catalyst charged in the reactor was prepared in the same manner as in example 1 except that the diameter of the pellets was 2.7mm, the loading was 28kg and the loading height was 1500 mm. The reaction raw material is a mixture of isobutane and butene, the mole ratio of alkane and alkene in the reactor is 800:1, the feeding quantity of fresh mixed alkene is 6.3kg/h, and the mass space velocity of the alkene is 0.09h^-1. The catalyst in the bed layer needs to be subjected to high-temperature deep regeneration once every 24 hours, the temperature of the mixed gas of nitrogen and air (same as that in example 1) is increased from normal temperature to 480 ℃, the catalyst in the bed layer is subjected to high-temperature oxidation regeneration for 3 hours under normal pressure, the bed layer needs to be cooled after regeneration, and the whole regeneration period is 24 hours. Returning the material in the reactor in the reaction state to the reactor after regeneration, continuing to use the regenerated catalyst to carry out alkylation reaction experiment, and cutting the reactor after reaction material withdrawalAnd (4) performing regeneration operation, and repeating the cycle.

After the apparatus of the above examples and comparative examples were continuously and stably operated for 1000 hours, the obtained alkylate was measured, and the test results are shown in Table 1.

TABLE 1

	RON	MON	Olefin C5+ yield	TMP/DMH	C9+ product wt.%
						Example 1	95.5	91.5	1.99	3.53	5.12
Example 2	95.8	92.0	2.0	3.62	5.08
						Example 3	95.7	92.0	2.0	3.60	5.11
Comparative example 1	95.2	91.3	1.96	3.24	6.76

As can be seen from table 1, the octane number of the alkylate obtained by the solid acid alkylation method provided by the present invention is slightly better than that of the fixed bed technology, the yield of olefin in the alkylate is higher, the alkylate has higher selectivity of the target product (trimethylpentane), and the yield of the C9+ product is lower. Compared with the example 1, the example 2 with the catalyst buffer tank has better product yield and target product selectivity. From the view of device operation, for the fixed bed alkylation technology, in order to realize the continuous and stable operation of the reaction device, at least more than two reactors are required to be switched (as comparative example 1), the catalyst in the bed layer is regenerated at high temperature at regular intervals, the temperature of the high temperature bed layer is reduced after deep regeneration, and the device frequently switches between the reaction temperature and the regeneration temperature, so that a plurality of problems are brought to the continuous and stable operation in industrial application, but the method provided by the invention adopts a liquid-solid axial moving bed reaction and regeneration device, and a single set of (set of) equipment can meet the requirements, thereby reducing the investment cost of the device, and in addition, the continuous operation of the catalyst reaction and regeneration is realized by leading the deactivated catalyst particles out of the liquid-solid axial moving reactor for deep regeneration on the premise of not influencing the stable operation of the reaction device, the catalyst in the device has stable equilibrium activity, and the selectivity of the target product in the alkylate oil is improved. Therefore, the method provided by the invention has better industrial application prospect.

The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.

Claims

1. A solid acid alkylation process comprising:

the method is carried out in a liquid-solid axial moving bed reaction and regeneration device, wherein the liquid-solid axial moving bed reaction and regeneration device comprises an axial moving bed reactor (1), a spent catalyst receiver (5), a catalyst regenerator (4) and a regenerant receiver (6) which are sequentially connected, wherein a catalyst outlet of the regenerant receiver (6) is communicated with a catalyst inlet of the axial moving bed reactor (1); the axial moving bed reactor (1) is provided with at least two catalyst bed layers (3) which are arranged up and down, and a feed inlet (2) is arranged above each catalyst bed layer (3) of the axial moving bed reactor (1); a catalyst conveying pipe (16) is arranged between two adjacent catalyst bed layers (3) so that the catalyst can move from top to bottom in the axial moving bed reactor (1);

liquid phase raw materials are fed into the axial moving bed reactor (1) from a feed inlet arranged above each catalyst bed layer (3) to be in contact reaction with the catalyst.

2. The method of claim 1, wherein the method further comprises: and circulating a reaction product obtained at the bottom of the axial moving bed reactor (1) to the position above the uppermost stream catalyst bed layer, mixing the reaction product with the liquid phase raw material, and feeding the mixture.

3. The process according to claim 1 or 2, wherein the reaction temperature in the axial moving bed reactor is 30-100 ℃ and the pressure is 1-3.4 MPa;

preferably, the mass space velocity of the material entering each catalyst bed layer calculated by olefin is 0.05-1h^-1；

Preferably, the molar ratio of isoparaffin to olefin entering each catalyst bed is 200-: 1;

preferably, the residence time of the catalyst in the axial moving bed reactor is between 6 and 72 h.

4. The process of any one of claims 1 to 3, wherein the catalyst is a solid acid catalyst comprising a molecular sieve and a refractory inorganic oxide, the molecular sieve being present in an amount of 65 to 95 wt% and the refractory inorganic oxide being present in an amount of 5 to 35 wt%, based on the total amount of the solid acid catalyst;

preferably, the molecular sieve is at least one selected from FAU structure zeolite, BETA structure zeolite and MFI structure zeolite, and the heat-resistant inorganic oxide is alumina and/or silica;

further preferably, the solid acid catalyst further contains a metal active component selected from at least one of Fe, Co, Ni, Pd, and Pt in an amount of 0.15 to 2 wt% based on the total amount of the solid acid catalyst.

5. The method according to any one of claims 1 to 4, wherein a separating member (10) is arranged between two adjacent catalyst beds (3), the separating member (10) is communicated with a catalyst conveying pipe (16), the separating member (10) is used for separating materials and catalysts after reaction of the upstream catalyst bed, and the catalysts separated by the separating member (10) move downwards through the catalyst conveying pipe (16).

6. The method according to any one of claims 1 to 5, wherein a reaction material baffle (11) is arranged between two adjacent catalyst beds (3), and the reaction material baffle (11) is used for enhancing the mixing of the reacted material and the liquid fresh raw material fed from the feeding port (2);

preferably, the reaction material baffle (11) comprises a main shaft (111) and a conveying part (112) spirally extending along the axial direction of the main shaft;

preferably, the reaction material baffle (11) comprises a plurality of baffles (113), the baffles (113) are arranged along the axial direction of the axial moving bed reactor (1) in an inclined manner, and the baffles (113) are arranged in a staggered manner to form a flow channel for the reaction material to pass through.

7. The method according to any one of claims 1-6, wherein a catalyst distribution member is arranged between two adjacent catalyst beds (3), and the catalyst distribution member is used for distributing the catalyst at the outlet of the catalyst conveying pipe (16);

preferably, the catalyst distribution piece comprises a conical distribution baffle (12), and the conical distribution baffle (12) is coaxially arranged with the catalyst conveying pipe (16); further preferably, the number of the conical distribution baffles (12) and the number of the catalyst conveying pipes (16) are the same;

further preferably, the catalyst distribution piece further comprises a horizontal distribution baffle (13) arranged below the conical distribution baffle (12), and holes for the catalyst to pass through are formed in the horizontal distribution baffle (13).

8. The method as claimed in any one of claims 1 to 7, wherein the catalyst at the bottom of the axial moving bed reactor (1) is conveyed to a spent catalyst receiver (5) to remove liquid-phase materials carried in the catalyst, and then conveyed to a catalyst regenerator (4) for regeneration;

preferably, the superficial flow velocity of the regeneration medium in the catalyst regenerator (4) is in the range of from 0.003 to 0.8m/s, more preferably in the range of from 0.02 to 0.5 m/s.

9. A process according to any one of claims 1 to 8, wherein the catalyst regenerator (4) is provided with a fresh catalyst inlet for fresh catalyst to enter the catalyst regenerator (4).

10. The method according to any one of claims 1 to 9, wherein the spent catalyst receiver (5), the catalyst regenerator (4) and the regenerant receiver (6) are arranged from top to bottom in sequence, and a catalyst flow line between the spent catalyst receiver (5), the catalyst regenerator (4) and the regenerant receiver (6) is arranged vertically or inclined at an angle of not less than 40 degrees with respect to the horizontal plane.

11. The method according to any one of claims 1 to 10, wherein a first particle flow regulator (25) is arranged on a connecting pipeline between a catalyst outlet of the axial moving bed reactor (1) and a catalyst inlet of the spent agent receiver (5); a second particle flow regulator (33) is arranged on a communicating pipeline between a catalyst outlet of the regenerant receiver (6) and a catalyst inlet of the axial moving bed reactor (1);

preferably, the first particle flow regulator (25) and the second particle flow regulator (33) are each independently an L-shaped or approximately L-shaped material delivery valve group.

12. The method according to any one of claims 1 to 11, wherein the device further comprises a catalyst buffer tank (38), the catalyst buffer tank (38) is arranged between the axial moving bed reactor (1) and the spent catalyst receiver (5), a catalyst inlet of the catalyst buffer tank (38) is communicated with a catalyst outlet of the axial moving bed reactor (1), and a catalyst outlet of the catalyst buffer tank (38) is communicated with a catalyst inlet of the spent catalyst receiver (5).