CN111905839B

CN111905839B - Partial regeneration method of catalyst for preparing olefin from methanol and/or dimethyl ether and method for preparing olefin from methanol and/or dimethyl ether

Info

Publication number: CN111905839B
Application number: CN201910388837.0A
Authority: CN
Inventors: 张今令; 叶茂; 刘中民; 周吉彬; 张涛; 王贤高; 唐海龙; 王静
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2019-05-10
Filing date: 2019-05-10
Publication date: 2023-06-06
Anticipated expiration: 2039-05-10
Also published as: CN111905839A

Abstract

The application discloses a partial regeneration method of a catalyst for preparing olefin from methanol and/or dimethyl ether, which comprises the following steps: introducing mixed gas into a regeneration zone containing a catalyst to be regenerated, and performing partial regeneration reaction to obtain a regenerated catalyst; the mixed gas contains water vapor and air; in the regenerated catalyst, at least a portion of the regenerated catalyst has a coke content of greater than 1%. The method utilizes the coupling activation of steam and air mixture to deactivate the catalyst, selectively eliminates part of carbon deposit in the catalyst to be regenerated, and obtains the partially regenerated catalyst for preparing olefin by methanol. In another aspect, the application also provides a method for preparing olefin from methanol and/or dimethyl ether by partially regenerating the catalyst for preparing olefin from methanol, which is regenerated by the method.

Description

Partial regeneration method of catalyst for preparing olefin from methanol and/or dimethyl ether and method for preparing olefin from methanol and/or dimethyl ether

Technical Field

The application relates to a partial regeneration method of a catalyst for preparing olefin from methanol and/or dimethyl ether and a method for preparing olefin from methanol and/or dimethyl ether, belonging to the field of chemical catalysts.

Background

Ethylene and propylene are important basic raw materials for national economy and play an important strategic role in the development of petrochemical and chemical industries. The ethylene production raw materials in China mainly comprise naphtha, and the cost is high. The industrial technology for preparing the olefin from the methanol starts from coal, and adopts a fluidized bed process to successfully prepare the high-selectivity low-carbon olefin by utilizing the SAPO catalyst. However, after a period of time of reaction, the SAPO catalyst is deactivated by carbon deposition, and carbon burning regeneration is required to restore the activity and selectivity of the catalyst.

In the prior art, the regeneration process of the catalyst for preparing olefin from methanol adopts a mixed gas mainly comprising air as a regeneration gas, and the phenomenon of 'flying temperature' or 'afterburning' in the regeneration process is prevented by adjusting the amount of auxiliary gas in a regeneration feed gas.

However, this process generates significant amounts of the greenhouse gas CO ₂ Is not beneficial to environmental protection, and reduces the utilization rate of methanol carbon atoms. In addition, if the catalyst is partially regenerated by using air to burn carbon, the burning rate is higher, which is not beneficial to control of the carbon residue of the catalyst and increases the difficulty in the operation process.

Disclosure of Invention

According to one aspect of the application, a partial regeneration method of a methanol-to-olefin catalyst and/or dimethyl ether-to-olefin catalyst is provided, wherein steam and air mixture is utilized to couple and activate an inactivated catalyst, so that partial carbon deposit in the catalyst to be regenerated is selectively eliminated, and the methanol-to-olefin catalyst with better olefin selectivity and partial regeneration is obtained.

The partial regeneration method of the catalyst for preparing olefin from methanol and/or dimethyl ether is characterized by comprising the following steps: introducing mixed gas into a regeneration zone containing a catalyst to be regenerated, and performing partial regeneration reaction to obtain a regenerated catalyst;

the mixed gas contains water vapor and air;

in the regenerated catalyst, at least a portion of the regenerated catalyst has a coke content of greater than 1%.

According to the method, air and water vapor are mixed, the fluidity of the air is utilized, the selectivity of the water vapor to carbon deposition near an active site is improved, the reaction activity is improved, and the obtained partially regenerated catalyst has better low-carbon olefin selectivity and simultaneously maintains better methanol conversion rate.

When only air is used for regeneration (or when the air content is higher), the regeneration rate is high, the catalyst is partially regenerated by air charcoal burning, the property of the catalyst charcoal residue is greatly changed, the catalysis of the regenerated catalyst containing coke in the reaction process is weakened, and the selectivity of the low-carbon olefin cannot reach the maximum. And when only using steam for regeneration, the property and content of the catalyst carbon residue can be controlled by the conditions of temperature, airspeed, time and the like, so that the selectivity of low-carbon olefin in the product is ensured and improved. However, the steam oxidation is too weak, the regeneration temperature is required to be high, the regeneration time is long, the accumulation of carbon is easy to occur, and the regeneration life is not ideal.

Specifically, under the action of the steam and air mixture with lower air content, the advantages of the two atmospheres are simultaneously exerted, and the disadvantages are complemented. Avoiding a large amount of greenhouse gas CO generated in the traditional air non-selective deep charcoal burning process ₂ Meanwhile, the catalyst after partial regeneration can improve the olefin selectivity in the MTO reaction product and improve the economical efficiency of MTO.

The catalyst treated by the method can cross or shorten the induction period which is needed by a fresh catalyst or a completely regenerated catalyst, so that the catalyst is always in an optimal performance state, and meanwhile, the ratio of the low-carbon olefin can be regulated and controlled due to the control of the carbon residue property of the catalyst, so that the economy of preparing the olefin from the methanol is improved.

Optionally, the volume ratio of the water vapor to the air in the mixed gas ranges from 1:0.001 to 1:0.8;

preferably, the volume ratio of the water vapor to the air in the mixed gas ranges from 1:0.01 to 1:0.5;

further preferably, the volume ratio of the water vapor to the air in the mixed gas ranges from 1:0.01 to 1:0.14.

Optionally, in the partial regeneration reaction, the contact time of the mixed gas and the catalyst to be regenerated is 10-200 min.

Optionally, at least a portion of the regenerated catalyst has a coke content of 1.1 to 8%;

preferably, the coke content of the regenerated catalyst obtained after the partial regeneration reaction in the regenerator is 2.8% -7.5%. The coke content of the regenerated catalyst as used herein refers to the coke content of the regenerated catalyst as a whole.

The lower limit of the coke content range of the regenerated catalyst obtained after the partial regeneration reaction in the regenerator is selected from 1.2%, 1.5%, 1.6%, 1.7%, 1.8%, 2%, 2.94%, 3%, 3.89%, 4%, and the upper limit is selected from 2%, 2.94%, 3%, 3.89%, 4%, 4.7%, 5.1%, 5.9%, 6%, 7%, 8%.

Further preferably, the coke content of the regenerated catalyst obtained after the partial regeneration reaction in the regenerator is 1.6% to 7%.

In the present application, the calculation formula of the coke content ω of the catalyst is shown as the following formula I:

coke content ω= (m) _250℃ -m _900℃ )/m _250℃ X 100% formula I

In the formula I, omega is the coke content of the catalyst in mass percent, m _250℃ For the mass of the catalyst when the temperature of the catalyst is raised to 250 ℃ under the air atmosphere, m _900℃ The mass of the catalyst was found to be the same when the temperature was raised to 900 ℃.

Optionally, the space velocity of the water vapor in the mixed gas which is introduced into the regenerator is 0.1h ^-1 ～10h ^-1 Airspeed of air is 0.01h ^-1 ～6h ^-1 。

Optionally, the partial regeneration reaction is carried out at a temperature of 500 ℃ to 700 ℃;

preferably, the partial regeneration reaction is carried out at 600 to 680 ℃.

Optionally, the coke content of the catalyst to be regenerated is 6% -14%.

Optionally, the methanol-to-olefin catalyst is subjected to methanol-to-olefin reaction in a fluidized bed reactor, the deactivated methanol-to-olefin catalyst is conveyed to a regenerator for partial regeneration reaction, the regenerated catalyst is obtained as a partial regenerated catalyst, and the partial regenerated catalyst is recycled to the fluidized bed reactor;

the catalyst for preparing olefin from methanol is a molecular sieve containing silicon aluminum phosphate;

the catalyst for preparing olefin from methanol is a fluidized bed catalyst.

In this application, "olefin" means: ethylene and propylene.

According to a further aspect of the present application, there is provided a method for preparing olefins from methanol and/or dimethyl ether, wherein a fluidized bed reaction process is used to partially regenerate the catalyst to be regenerated according to the above method for partially regenerating the catalyst for preparing olefins from methanol.

Optionally, introducing raw material gas containing methanol and/or dimethyl ether into a fluidized bed reactor loaded with a catalyst for preparing olefin from methanol to perform reaction for preparing olefin from methanol;

conveying the catalyst to be regenerated to a regeneration zone, introducing the mixed gas into the regeneration zone, and performing partial regeneration reaction to obtain a regenerated catalyst;

returning the regenerated catalyst to the fluidized bed reactor

Optionally, the catalyst for preparing olefin from methanol contains a silicon aluminum phosphate molecular sieve.

The beneficial effects that this application can produce include:

1) The mixture of water vapor and air is used as regeneration gas to carry out gasification partial regeneration on carbon deposit in the catalyst, and gasification products of the catalyst are CO and H ₂ Mainly, small amount of CO ₂ Can be recycled, and improves the utilization rate of methanol carbon atoms;

2) The advantages of the steam and the air are respectively exerted by adjusting the proportion of the steam and the air, so that the control of the property and the content of the carbon residue of the catalyst is facilitated, the steam vaporization carbon deposition reaction needs to be near the active site of the catalyst, and the transformation of the active site carbon can be quickened by a small amount of air, so that the carbon deposit is selectively eliminated;

3) The catalyst which is partially regenerated by mixing steam and air is subjected to MTO reaction, so that the selectivity of the initial low-carbon olefin is improved to be about 62 percent of the fully regenerated catalyst to be within the range of 65-83 percent, and the highest selectivity is ensured;

4) The partially regenerated catalyst is mixed with water vapor and air for MTO reaction, the reactant methanol is almost completely converted, and the conversion rate is nearly 100% as same as that of the fresh agent.

Drawings

FIG. 1 is a schematic diagram of a method for regenerating a catalyst by a steam and air coupling part provided by the invention;

FIG. 2 is a graph showing the results of catalytic performance of the fresh catalyst of example 1 of the present application;

FIG. 3 is sample D1 of comparative example 1 of the present application ^# A catalytic performance test result graph of (2);

FIG. 4 is sample 1 in example 2 of the present application ^# A catalytic performance test result graph of (2);

FIG. 5 is sample 2 in example 3 of the present application ^# A catalytic performance test result graph of (2);

FIG. 6 is sample 3 in example 4 of the present application ^# A catalytic performance test result graph of (2);

FIG. 7 is sample 4 in example 5 of the present application ^# A catalytic performance test result graph of (2);

FIG. 8 is sample 5 in example 6 of the present application ^# A catalytic performance test result graph of (2);

FIG. 9 is sample 6 in example 7 of the present application ^# A catalyst catalytic performance test result graph;

FIG. 10 is sample 7 in example 8 of the present application ^# A catalytic performance test result graph of (2);

FIG. 11 is sample 5 in example 9 of the present application ^# -10 catalytic performance test results plot;

FIG. 12 is sample D2 of comparative example 2 of the present application ^# A catalytic performance test result graph of (2);

FIG. 13 is XRD patterns of samples obtained in examples 1 and 9 of the present application, wherein a) is the XRD pattern of the deactivated catalyst A obtained in example 1; b) Sample 5 obtained in example 9 ^# -10 XRD spectrum.

Detailed Description

The present application is described in detail below with reference to examples, but the present application is not limited to these examples.

The catalyst used in this application is a commercially available methanol to olefins catalyst.

The coke content of the catalyst was determined as follows:

heating the catalyst to 250 ℃ in air, wherein the recording quality is m _250℃ The method comprises the steps of carrying out a first treatment on the surface of the Then the catalyst is heated to 900 ℃ in the air, and the recording quality is m _900℃ The method comprises the steps of carrying out a first treatment on the surface of the The carbon deposition of the catalyst is determined by the following formula I:

coke content ω= (m) _250℃ -m _900℃ )/m _250℃ X 100% formula I

The methanol conversion, ethylene selectivity and propylene selectivity in the examples were all calculated on a carbon mole basis.

In the examples, XRD characterization of the samples was performed using a Philips X' Pert PROX type X-ray diffractometer, copper target, K _α Radiation source

The instrument operating voltage was 40kv and the operating current was 40mA.

FIG. 1 is a process scheme for the production of olefins from methanol using a partial regeneration process for the methanol-to-olefins catalyst described herein. The method comprises the following steps: introducing raw materials containing methanol and/or dimethyl ether into a reactor, and allowing product gas (ethylene and propylene) to leave from the top of the reactor after reaction; the deactivated catalyst enters a catalyst regenerator through a stripper; introducing a mixed gas of air and water vapor with a specific proportion into a catalyst regenerator to perform partial regeneration reaction of the deactivated catalyst to generate CO and H ₂ 、C ₂ O leaves the catalyst regenerator and the regenerated catalyst is returned to the reactor via a riser.

Example 1

4g of a commercially used methanol-to-olefin catalyst, the active component of which is SAPO-34, with the number of DMTO-1, is filled into a fixed fluidized bed reactor to carry out the reaction of preparing the olefin from the methanol, wherein the raw material of the reaction of preparing the olefin from the methanol is aqueous solution of methanol with the concentration of 80 weight percent, the reaction temperature is 490 ℃, the pressure is 0.1MPa, and the methanol airspeed is 2.1h ^-1 . The reaction time is 107 minutes, and the methanol conversion is obtainedThe conversion and olefin selectivity and the results are shown in FIG. 2.

The catalyst obtained after the completion of the reaction was designated as "deactivated catalyst A". The coke content of deactivated catalyst A was determined to be 10.2%.

Comparative example 1

Roasting the deactivated catalyst A in a muffle furnace at 600deg.C for 6 hr to obtain a completely regenerated catalyst, designated as sample D1 ^# . Determination of sample D1 ^# The coke content of (2) was 0.05%.

Regenerated catalyst sample D1 was subjected to the reaction conditions for methanol to olefins in example 1 ^# The evaluation reaction of methanol to olefin was carried out for 89 minutes, and the results of the conversion of methanol and the selectivity of olefin were shown in FIG. 3.

Example 2

The deactivated catalyst A is placed in a reactor, nitrogen gas with the flow rate of 100mL/min is introduced into the reactor for purging, the temperature of the reactor is raised to 650 ℃, the temperature is constant for 10min, and the nitrogen is closed. Then water vapor and air are introduced, the volume ratio of the water vapor to the air is 1:0.4, and the mass airspeed of the water vapor is 8h ^-1 Air mass space velocity of 4.8h ^-1 The reaction was maintained for 20min. The coke content of the catalyst was determined to be 1.2%.

Switching to nitrogen atmosphere, cooling the reactor to 490 deg.C, and keeping constant for 20min to obtain partially regenerated catalyst, which is denoted as sample 1 ^# 。

Sample 1 of the partially regenerated catalyst was subjected to the reaction conditions for the preparation of olefins from methanol as in example 1 ^# The evaluation reaction of methanol to olefins was carried out for 72 minutes with methanol conversion and olefin selectivity results shown in FIG. 4.

Example 3

The deactivated catalyst A obtained in the method of example 1 is placed in a reactor, nitrogen gas with the flow rate of 100mL/min is introduced into the reactor for purging, the temperature of the reactor is raised to 680 ℃, the temperature is constant for 10min, the nitrogen is closed, then water vapor and air are introduced, the volume ratio of the water vapor to the air is 1:0.02, and the mass space velocity of the water vapor is 2h ^-1 Air mass space velocity of 0.06h ^-1 Hold for 180min. The coke content of the catalyst was determined to be 1.6%.

Switching to nitrogen atmosphere, cooling the reactor to 490 ℃ and keeping the temperature constant for 20min to obtain a partially regenerated catalyst, which is marked as sample 2 ^# 。

Sample 2 of the partially regenerated catalyst was subjected to the reaction conditions for the preparation of olefins from methanol as in example 1 ^# The evaluation reaction of methanol to olefins was carried out for 72 minutes with the results of methanol conversion and olefin selectivity shown in FIG. 5.

Example 4

The deactivated catalyst A obtained in example 1 was placed in a reactor, nitrogen gas with a flow rate of 100mL/min was introduced into the reactor, the reactor was warmed to 620℃and kept constant for 10min, the nitrogen gas was turned off, then water vapor and air were introduced, the volume ratio of water vapor and air was 1:0.14, and the mass space velocity of water vapor was 3h ^-1 Air mass space velocity of 0.63h ^-1 Hold for 60min. The coke content of the catalyst was measured to be 2.8%.

Switching to nitrogen atmosphere, cooling the reactor to 490 ℃ and keeping the temperature constant for 20min to obtain a partially regenerated catalyst, which is marked as sample 3 ^# 。

Sample 3 of the partially regenerated catalyst was subjected to the reaction conditions for the preparation of olefins from methanol as in example 1 ^# The evaluation reaction of methanol to olefins was carried out for 72 minutes with the results of methanol conversion and olefin selectivity shown in FIG. 6.

Example 5

The deactivated catalyst A obtained in example 1 was placed in a reactor, nitrogen gas with a flow rate of 100mL/min was introduced into the reactor, the reactor was warmed to 650℃and kept constant for 10min, the nitrogen gas was turned off, then water vapor and air were introduced, the volume ratio of water vapor and air was 1:0.1, and the mass space velocity of water vapor was 6h ^-1 Air mass space velocity of 0.9h ^-1 Hold for 40min. The coke content of the catalyst was determined to be 4.7%.

Switching to nitrogen atmosphere, cooling the reactor to 490 ℃ and keeping the temperature constant for 20min to obtain a partially regenerated catalyst, which is marked as sample 4 ^# 。

Sample 4 of the partially regenerated catalyst was subjected to the reaction conditions for the preparation of olefins from methanol as in example 1 ^# Evaluation reaction of methanol to olefinsThe reaction time was 56 minutes, and the results of methanol conversion and olefin selectivity are shown in FIG. 7.

Example 6

The deactivated catalyst A obtained in example 1 was placed in a reactor, nitrogen gas with a flow rate of 100mL/min was introduced into the reactor, the reactor was warmed to 600℃and kept constant for 10min, the nitrogen gas was turned off, then water vapor and air were introduced, the volume ratio of water vapor and air was 1:0.1, and the mass space velocity of water vapor was 6h ^-1 Air mass space velocity of 0.9h ^-1 Hold for 30min. The coke content of the catalyst was determined to be 5.1%.

Switching to nitrogen atmosphere, cooling the reactor to 490 deg.C, keeping constant for 20min to obtain partially regenerated catalyst, which is denoted as sample 5 ^# 。

Sample 5 was partially regenerated catalyst according to the reaction conditions for methanol to olefins in example 1 ^# The evaluation reaction of methanol to olefins was carried out for 39 minutes with methanol conversion and olefin selectivity results shown in FIG. 8.

Example 7

The deactivated catalyst A obtained in example 1 was placed in a reactor, nitrogen gas with a flow rate of 100mL/min was introduced into the reactor, the reactor was warmed to 650℃and kept constant for 10min, the nitrogen gas was turned off, then water vapor and air were introduced, the volume ratio of water vapor and air was 1:0.06, and the mass space velocity of water vapor was 6h ^-1 Air mass space velocity of 0.54h ^-1 Hold for 50min. The coke content of the catalyst was determined to be 5.9%.

Switching to nitrogen atmosphere, cooling the reactor to 490 ℃ and keeping the temperature constant for 20min to obtain a partially regenerated catalyst, which is marked as sample 6 ^# 。

Sample 6 was partially regenerated catalyst as described in example 1 for methanol to olefins reaction conditions ^# The evaluation reaction of methanol to olefins was carried out for 39 minutes with the results of methanol conversion and olefin selectivity shown in FIG. 9.

Example 8

The deactivated catalyst A obtained in example 1 was placed in a reactor, and a nitrogen gas purge was introduced into the reactor at a flow rate of 100mL/min, and the reactor was elevatedHeating to 550deg.C, keeping constant for 10min, closing nitrogen, and introducing water vapor and air at a volume ratio of 1:0.06, wherein the mass space velocity of water vapor is 0.8h ^-1 Air mass space velocity of 0.072h ^-1 Hold for 90min. The coke content of the catalyst was determined to be 7.5%.

Switching to nitrogen atmosphere, cooling the reactor to 490 deg.C, keeping constant for 20min to obtain partially regenerated catalyst, which is denoted as sample 7 ^# 。

Sample 7 was partially regenerated catalyst as described in example 1 for methanol to olefins reaction conditions ^# The evaluation reaction of methanol to olefins was carried out for 39 minutes with the results of methanol conversion and olefin selectivity shown in FIG. 10.

Example 9

The procedure and conditions in example 6 were followed, and the "catalyst regeneration-methanol to olefin reaction" procedure was repeated 10 times, and the partially regenerated catalyst obtained by 10 catalyst regenerations was designated as sample 5 ^# -10。

Sample 5 was partially regenerated catalyst according to the reaction conditions for methanol to olefins in example 1 ^# -10 the methanol to olefins evaluation reaction was carried out for 39 minutes with methanol conversion and olefin selectivity results shown in figure 11.

Comparative example 2

The deactivated catalyst A is placed in a reactor, nitrogen gas with the flow rate of 100mL/min is introduced into the reactor for purging, the temperature of the reactor is raised to 650 ℃, the temperature is constant for 10min, and the nitrogen is closed. Then nitrogen and air are introduced, the volume ratio of the nitrogen to the air is 1:0.1, and the mass airspeed of the nitrogen is 6h ^-1 Air mass space velocity of 0.9h ^-1 Maintaining for 40min to obtain regenerated catalyst, designated as sample D2 ^# . Sample D2 ^# The coke content was 3.5%.

Switching to nitrogen atmosphere, cooling the reactor to 490℃and keeping the temperature constant for 20min, and then carrying out the reaction under the conditions of the methanol-to-olefin reaction in example 1 on the regenerated catalyst sample D2 ^# The evaluation reaction of methanol to olefins was carried out for 72 minutes with the results of methanol conversion and olefin selectivity shown in FIG. 12.

Example 10

Deactivated catalyst A and sample 5, respectively, by XRD ^# Characterization of-10, results see FIG. 13, in deactivated catalyst A (see FIG. 13 a)) and sample 5 ^# -10 (see fig. 13 b)), sample 5 ^# The peak intensity of the-10 highest diffraction peak was 95% of the peak intensity of the deactivated catalyst a highest diffraction peak.

The catalyst partially regenerated method is adopted, the crystallinity of the catalyst regenerated for multiple times is close to that of a fresh catalyst, and the catalyst partially regenerated by using the mixed gas of the water vapor and the air in a certain proportion in the temperature range is prevented from dealuminating, so that the catalyst can be recycled for a long time.

The conditions for the partial regeneration treatment of the deactivated catalyst in examples 2 to 9 are shown in Table 1.

TABLE 1

As a result of the experiment for preparing olefin from methanol, the catalyst activity was reduced when the conversion of methanol (including dimethyl ether) was less than 97% by setting the reaction time to be 3 minutes as the initial activity. The activity retention time and the highest selectivity for reducing the pre-olefins are important parameters for the reaction result of methanol to olefins.

As can be seen from FIG. 2, the initial activity of the fresh catalyst in the methanol-to-olefin reaction was 99.57% in terms of methanol conversion and 65.34% in terms of olefin selectivity. After the activity is maintained for 70 minutes, the conversion rate of methanol is obviously reduced, the olefin selectivity of the fresh catalyst is gradually reduced after the reaction is carried out for 70 minutes, and the maximum olefin selectivity is 86.62 percent.

As can be seen from FIG. 3, sample D1 is a comparative example ^# As a catalyst, the initial activity of the reaction for preparing olefin from methanol, the conversion rate of methanol was 99.6%, and the selectivity of olefin was 65.9%. After activity was maintained for 70 minutes, sample D-1 ^# The methanol conversion of (2) was significantly reduced and 40% was obtained when the reaction was carried out for 90 minutes. After the reaction for 70 minutes in the process of preparing olefin from methanol, the selectivity of the olefin gradually decreases, and the highest activity selectivity of the olefin is 86.70 percent。

As can be seen from FIG. 4, sample 1 ^# As a catalyst, the initial activity of the reaction for preparing olefin from methanol is 99.5 percent, the selectivity of the olefin is 66.2 percent, and the methanol conversion rate is 85 percent when the reaction for reducing the methanol conversion rate is carried out for 70 minutes after the activity is kept for about 54 minutes; after 54 minutes of reaction, the olefin selectivity of the catalyst gradually decreased, the highest olefin selectivity was 84.00%, the reaction was carried out for about 70 minutes, and the olefin selectivity was 77.71%.

As can be seen from FIG. 5, sample 2 ^# The initial activity of the reaction for preparing olefin from methanol is used as a catalyst, the conversion rate of the methanol is 99.30%, and the selectivity of the olefin is 66.60%. After the activity was maintained for about 54 minutes, the methanol conversion of the partially regenerated catalyst in example 3 was lowered, and the methanol conversion was 85% when the reaction was carried out for 70 minutes. After 54 minutes of reaction for preparing olefin from methanol, the olefin selectivity of the partially regenerated catalyst gradually decreases, the highest olefin selectivity is 85.20%, the reaction is carried out for about 70 minutes, and the olefin selectivity is 78.71%.

As can be seen from FIG. 6, sample 3 ^# As a catalyst, the initial activity of the reaction for preparing olefin from methanol, the conversion rate of methanol was 99.43%, and the selectivity of olefin was 69.95%. After the activity was maintained for about 54 minutes, the methanol conversion rate of the partially regenerated catalyst in example 4 was lowered, and the methanol conversion rate was 83% when the reaction was carried out for 70 minutes. After 55 minutes of reaction of preparing olefin from methanol, the olefin selectivity of the partially regenerated catalyst gradually decreases, the highest olefin selectivity is 87.01%, the reaction is carried out for about 70 minutes, and the olefin selectivity is 81.05%.

As can be seen from FIG. 7, sample 4 ^# As a catalyst, the initial activity of the reaction for preparing olefin from methanol, the conversion rate of methanol was 99.67%, and the selectivity of olefin was 74.26%. After the activity was maintained for about 37 minutes, the methanol conversion of the partially regenerated catalyst in example 5 was lowered, and the methanol conversion was 50% when the reaction was carried out for 54 minutes. After 37 minutes of reaction of preparing olefin from methanol, the olefin selectivity of the partially regenerated catalyst gradually decreases, the highest olefin selectivity is 86.38 percent, the reaction is carried out for about 54 minutes, and the olefin selectivity is 73.05 percent.

As can be seen from FIG. 8, in the form of a sample5 ^# As a catalyst, the initial activity of the reaction for preparing olefin from methanol, the conversion rate of methanol was 99.73%, and the selectivity of olefin was 80.01%. After the activity was maintained for about 20 minutes, the methanol conversion of the partially regenerated catalyst in example 6 was lowered, and the methanol conversion was 50% when the reaction was carried out for 37 minutes. After the reaction of preparing olefin from methanol for 20 minutes, the olefin selectivity of the partially regenerated catalyst gradually decreases, the highest olefin selectivity is 85.28%, the reaction is carried out for about 37 minutes, and the olefin selectivity is 67.47%.

As can be seen from FIG. 9, sample 6 ^# As a catalyst, the initial activity of the reaction for preparing olefin from methanol, the conversion rate of methanol was 99.72%, and the selectivity of olefin was 79.74%. After the activity was maintained for about 3 minutes, the methanol conversion of the partially regenerated catalyst in example 7 was lowered, and the methanol conversion was 20% when the reaction was carried out for 37 minutes. After the reaction of preparing olefin from methanol for 3 minutes, the olefin selectivity of the partially regenerated catalyst gradually decreases, the highest olefin selectivity is 79.74%, the reaction is carried out for about 37 minutes, and the olefin selectivity is 45.2%.

As can be seen from FIG. 10, sample 7 ^# As a catalyst, the initial activity of the reaction for preparing olefin from methanol, the conversion rate of methanol was 99.47%, and the selectivity of olefin was 82.97%. When the activity was maintained for about 3 minutes, the methanol conversion rate of the partially regenerated catalyst in example 8 was lowered, and when the reaction was carried out for 37 minutes, the methanol conversion rate was 20%. After the reaction of preparing olefin from methanol for 3 minutes, the olefin selectivity of the partially regenerated catalyst gradually decreases, the highest olefin selectivity is 82.97%, the reaction is carried out for about 37 minutes, and the olefin selectivity is 30.72%.

As can be seen from FIG. 11, sample 5 ^# -10 is catalyst, the initial activity of the reaction for preparing olefin from methanol, the conversion rate of methanol is 99.74%, and the selectivity of olefin is 80.48%. When the activity was maintained for about 20 minutes, the methanol conversion rate of the partially regenerated catalyst in example 9 was lowered, and when the reaction was carried out for 37 minutes, the methanol conversion rate was 25%. After the reaction of preparing olefin from methanol for 20 minutes, the olefin selectivity of the partially regenerated catalyst gradually decreases, the highest olefin selectivity is 85.45%, the reaction is carried out for about 37 minutes, and the olefin selectivity is 67.22%.

Can be seen from FIG. 12The regeneration atmosphere is the mixture of nitrogen and air, and the sample D2 is obtained after regeneration ^# As sample D2 ^# As a catalyst, the initial activity of the reaction for preparing olefin from methanol, the conversion rate of methanol is 99.50 percent, and the selectivity of olefin is 70.70 percent. Sample D2 of the comparative example after about 37 minutes of activity ^# The methanol conversion rate of the partially regenerated catalyst was reduced, and the methanol conversion rate was 85.00% when the reaction was carried out for 54 minutes. After 37 minutes of reaction of preparing olefin from methanol, the olefin selectivity of the partially regenerated catalyst gradually decreases, the highest olefin selectivity is 83.50 percent, the reaction is carried out for about 54 minutes, and the olefin selectivity is 79.40 percent.

As can be seen by comparing fig. 2 and 3, the catalytic performance of the fully regenerated sample is not significantly different from that of the fresh catalyst. As can be seen by comparing fig. 3 with fig. 4 to 11, the present application uses a mixture of steam and air with a certain proportioning relationship to partially regenerate the catalyst for preparing olefin from methanol and/or dimethyl ether, compared with the completely regenerated catalyst: the initial activity, the methanol conversion rate is about 99%, the olefin yield is improved, especially the ethylene selectivity is improved greatly, and the induction period is shortened. Under suitable conditions, the olefin maximum selectivity is substantially comparable to, or even higher than, the full regeneration. Thus being beneficial to regulating the methanol-to-olefin reaction process carried out by the circulating fluidized bed, improving the olefin selectivity and generating gas H after regeneration ₂ CO and CH ₄ Mainly reduces the unit consumption of methanol and improves the utilization rate of C atoms.

As can be seen from comparing fig. 12 with fig. 7, the present application uses a mixture gas of steam and air with a certain proportioning relationship to partially regenerate the coking catalyst for preparing olefin from methanol and/or dimethyl ether, and compared with the technical scheme that the mixture gas of air and other gases with the same proportion is used as regeneration gas: the initial olefin selectivity is higher and the highest olefin selectivity is also higher during the time that activity is maintained. Regeneration of coked catalyst to produce gas H ₂ CO and CH ₄ CO generated by regenerating coked catalyst by mixing main comparative air with other gases ₂ And CO, C atom utilization is higher.

From the above results, it is found that the olefin selectivity and the life of the catalyst can be recovered after the partial regeneration of the coked catalyst for producing olefins from methanol and/or dimethyl ether by using a mixed gas of steam and air, and the olefin selectivity and the life of the partially regenerated catalyst can not be reduced or attenuated after the repeated partial regeneration. At the same time, XRD characterization is carried out on the catalyst regenerated for many times, and the crystallinity of the catalyst is found to be close to that of a fresh catalyst, which indicates that the catalyst can not be dealuminated by partial regeneration of the catalyst by mixing water vapor and air and mixing the air in the temperature range, so that the catalyst can be used for a long time.

The foregoing description is only a few examples of the present application and is not intended to limit the present application in any way, and although the present application is disclosed in the preferred examples, it is not intended to limit the present application, and any person skilled in the art may make some changes or modifications to the disclosed technology without departing from the scope of the technical solution of the present application, and the technical solution is equivalent to the equivalent embodiments.

Claims

1. A method for partially regenerating a catalyst for producing olefins from methanol and/or dimethyl ether, the method comprising: introducing mixed gas into a regeneration zone containing a catalyst to be regenerated, and performing partial regeneration reaction to obtain a regenerated catalyst;

the mixed gas contains water vapor and air;

the volume ratio of the water vapor to the air in the mixed gas is 1:0.01-1:0.5;

the partial regeneration reaction is carried out at 500-700 ℃;

the coke content of the catalyst to be regenerated is 6% -14%;

in the partial regeneration reaction, the contact time of the mixed gas and the catalyst to be regenerated is 10-200 min;

in the regenerated catalyst, the coke content of at least a part of the regenerated catalyst is 1.1% -8%.

2. The partial regeneration method of the catalyst for preparing olefin from methanol and/or dimethyl ether according to claim 1, wherein the volume ratio of water vapor to air in the mixed gas is 1:0.01-1:0.14.

3. The method for partially regenerating a catalyst for producing olefins from methanol and/or dimethyl ether according to claim 1, wherein the coke content of the regenerated catalyst is 2.8% to 7.5%.

4. The method for partially regenerating an olefin catalyst from methanol and/or dimethyl ether according to claim 1, wherein a space velocity of steam in the mixed gas introduced into the regenerator is 0.1h ^-1 ～10h ^-1 Airspeed of air is 0.01h ^-1 ～6h ^-1 。

5. The partial regeneration method of a catalyst for producing olefins from methanol and/or dimethyl ether according to claim 1, wherein the partial regeneration reaction is performed at 600 to 680 ℃.

6. A method for preparing olefin from methanol, which is characterized by comprising the following steps:

introducing a raw material gas containing methanol into a fluidized bed reactor loaded with a catalyst for preparing olefin from methanol to enter DD190053I

Carrying out methanol to prepare olefin reaction;

delivering the catalyst to be regenerated to a regeneration zone, and carrying out partial regeneration reaction on the catalyst to be regenerated to obtain a regenerated catalyst according to the partial regeneration method of the methanol-to-olefin catalyst of any one of claims 1 to 5;

the regenerated catalyst is returned to the fluidized bed reactor.

7. The method for producing olefin from methanol according to claim 6, wherein the catalyst for producing olefin from methanol contains a silicoaluminophosphate molecular sieve.