CN111905839A - 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 - Google Patents

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 the catalyst to be regenerated, and performing partial regeneration reaction to obtain a regenerated catalyst; the mixed gas contains water vapor and air; at least a portion of the regenerated catalyst has a coke content greater than 1%. The method selectively eliminates partial carbon deposit in the catalyst to be regenerated by coupling and activating the deactivated catalyst by using mixed gas of water vapor and air to obtain the partially regenerated catalyst for preparing the olefin from the methanol. The application also provides a method for preparing olefin from methanol and/or dimethyl ether by regenerating the obtained partially regenerated methanol-to-olefin catalyst 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 of national economy, and play an important strategic position in the development of petrochemical and chemical industries. The ethylene production raw material in China mainly takes naphtha as the main raw material, and the cost is higher. The industrial methanol-to-olefin technology starts from coal, utilizes SAPO catalysts and adopts a fluidized bed process to successfully prepare high-selectivity low-carbon olefin. However, after the SAPO catalyst is reacted for a period of time, carbon deposition causes deactivation, and carbon burning regeneration is needed to recover the activity and selectivity of the catalyst.

In the prior art, a mixed gas mainly comprising air is used as a regeneration gas in the regeneration process of the catalyst for preparing olefin from methanol, and the phenomenon of temperature runaway or tail combustion in the regeneration process is prevented by adjusting the amount of an auxiliary gas in a regeneration feed gas.

However, this process produces a large amount of the greenhouse gas CO₂Is not beneficial to environmental protection, and reduces the utilization rate of the carbon atoms of the methanol. In addition, if the catalyst is partially regenerated by air charcoal burning, the charcoal burning rate is high, which is not beneficial to controlling the residual charcoal amount 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 and/or dimethyl ether to olefin catalyst is provided, the method selectively eliminates partial carbon deposit in the catalyst to be regenerated by using a steam and air mixed gas coupling activated deactivated catalyst, and the methanol to olefin catalyst with better olefin selectivity and partial regeneration is obtained.

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

the mixed gas contains water vapor and air;

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

According to the method, air and water vapor are mixed, the mobility 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 partial regenerated catalyst has better selectivity of low-carbon olefin and keeps better methanol conversion rate.

When only air is used for regeneration (or the air content is higher), the regeneration rate is high, the catalyst is partially regenerated by burning the carbon through the air, so that the carbon residue property of the catalyst is greatly changed, the catalytic action of the regenerated catalyst containing the carbon is weakened in the reaction process, and the selectivity of the low-carbon olefin cannot reach the maximum value. When only water vapor is used for regeneration, the property and the 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, carbon accumulation is easily caused, and the regeneration life is not ideal.

Specifically, under the action of the mixed gas of water vapor and air with low air content, the advantages of two atmospheres are exerted simultaneously, and the disadvantages are complemented. Avoids a large amount of greenhouse gas CO generated in the traditional air non-selective deep carbon burning process₂Meanwhile, the partially regenerated catalyst can improve the olefin selectivity in the MTO reaction product and improve the economy of MTO.

The catalyst treated by the method can stride over or shorten the induction period which is necessary to pass by a fresh catalyst or a completely regenerated catalyst, so that the catalyst is always in the optimal performance state, and meanwhile, the proportion of 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 is 1: 0.01-1: 0.14.

Optionally, in the partial regeneration reaction, the contact time of the mixed gas and the catalyst to be regenerated is 10min to 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 means the coke content of the regenerated catalyst as a whole.

The regenerated catalyst obtained after the partial regeneration reaction in the regenerator has a coke content ranging from a lower limit selected from 1.2%, 1.5%, 1.6%, 1.7%, 1.8%, 2%, 2.94%, 3%, 3.89%, 4% and an upper limit 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 1.6-7%.

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

coke content omega ═ m_250℃-m_900℃)/m_250℃X 100% of formula I

In the formula I, omega is the coke content of the catalyst in percentage by mass, and m_250℃M is the mass of the catalyst when the temperature of the catalyst is raised to 250 ℃ at room temperature under the air atmosphere_900℃The mass of the catalyst at the time of temperature rise to 900 ℃.

Optionally, the space velocity of the water vapor in the mixed gas introduced into the regenerator is 0.1h^-1～10h^-1The space velocity 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 the temperature of 600-680 ℃.

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

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

the methanol-to-olefin catalyst is a molecular sieve containing silicon aluminum phosphate;

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

In the present application, "olefin" means: ethylene and propylene.

According to another aspect of the application, a method for preparing olefin from methanol and/or dimethyl ether is provided, wherein a fluidized bed reaction process is adopted, and the catalyst to be regenerated is partially regenerated according to the method for partially regenerating the catalyst for preparing olefin from methanol.

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

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

returning the regenerated catalyst to the fluidized bed reactor

Optionally, the methanol to olefin catalyst contains a silicoaluminophosphate 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 gasify and partially regenerate the carbon deposit in the catalyst, and the gasified product is CO and H₂Mainly, a small amount of CO₂The methanol can be recycled, so that the utilization rate of the carbon atoms of the methanol is improved;

2) the advantages of the water vapor and the air are respectively exerted by adjusting the proportion of the water vapor and the air, the control of the property and the content of the carbon residue of the catalyst is facilitated, the carbon deposition reaction of the water vapor in the vaporization process needs to be near the active site of the catalyst, and the conversion of the carbon at the active site can be accelerated by a small amount of air, so that the carbon deposition is selectively eliminated;

3) the MTO reaction is carried out by the catalyst which is partially regenerated by mixing the water vapor and the air, so that the selectivity of the initial low-carbon olefin is improved to be within the range of 65-83% from about 62% of the selectivity of the completely regenerated catalyst, and the highest selectivity of the low-carbon olefin is ensured;

4) the MTO reaction is carried out by the catalyst which is partially regenerated by mixing water vapor and air, the reactant methanol is nearly completely converted, and the conversion rate is the same as that of a fresh agent and is nearly 100 percent.

Drawings

FIG. 1 is a schematic view of a steam and air coupled partial regeneration process for a catalyst provided by the present invention;

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

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

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

FIG. 5 shows sample 2 of example 3 of the present application^#A graph of the catalytic performance test results of (1);

FIG. 6 shows sample 3 in example 4 of the present application^#A graph of the catalytic performance test results of (1);

FIG. 7 shows sample 4 of example 5 of the present application^#A graph of the catalytic performance test results of (1);

FIG. 8 shows sample 5 of example 6 of the present application^#A graph of the catalytic performance test results of (1);

FIG. 9 shows sample 6 of example 7 of the present application^#A catalytic performance test result chart of the agent;

FIG. 10 shows sample 7 of example 8 of the present application^#Measurement of catalytic PerformanceA test result chart;

FIG. 11 shows sample 5 in example 9 of the present application^#-10 of a catalytic performance test result graph;

FIG. 12 shows sample D2 of comparative example 2 of the present application^#A graph of the catalytic performance test results of (1);

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

Detailed Description

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

The catalyst used in the present application is a commercially available methanol to olefin catalyst.

The coke content of the catalyst is determined as follows:

the catalyst was warmed to 250 ℃ in air and the mass recorded as m_250℃(ii) a Then the catalyst is heated to 900 ℃ in the air, and the record mass is m_900℃(ii) a The amount of carbon deposition of the catalyst is determined by the following formula I:

coke content omega ═ m_250℃-m_900℃)/m_250℃X 100% of formula I

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

In the examples, the XRD characterization of the samples was carried out using an apparatus such as Philips X' Pert PROX type X-ray diffractometer, copper target, K_αRadiation source

The working voltage of the instrument is 40kv, and the working current is 40 mA.

FIG. 1 is a schematic diagram of a methanol to olefins process employing a partial regeneration process for a methanol to olefins catalyst as described herein. The method specifically comprises the following steps: introducing a raw material containing methanol and/or dimethyl ether into a reactor, and leaving product gas (ethylene and propylene) from the top of the reactor after reaction; the deactivated catalyst enters a catalyst regenerator through a stripper; introducing into a catalyst regeneratorThe mixed gas of air and steam with a specific proportion is subjected to partial regeneration reaction of the deactivated catalyst to generate CO and H₂、C₂O exits from the catalyst regenerator and regenerated catalyst returns to the reactor via the riser.

Example 1

4g of a commercially used methanol-to-olefin catalyst with an active component of SAPO-34 and a serial number of DMTO-1 is filled in a fixed fluidized bed reactor to carry out a reaction for preparing olefin from methanol, wherein the reaction raw material for preparing olefin from methanol is a methanol aqueous solution with the concentration of 80 wt%, the reaction temperature is 490 ℃, the pressure is 0.1MPa, and the space velocity of methanol is 2.1h^-1. The reaction time was 107 minutes, and methanol conversion and olefin selectivity were obtained, and the results are shown in FIG. 2.

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

Comparative example 1

The deactivated catalyst A was calcined in a muffle furnace at 600 deg.C for 6 hours to yield a fully regenerated catalyst designated sample D1^#. Measurement sample D1^#The coke content of (a) was 0.05%.

Sample D1 of the regenerated catalyst was prepared according to the reaction conditions for methanol to olefin as in example 1^#The methanol to olefin evaluation reaction was carried out for a reaction time of 89 minutes, and the results of the methanol conversion and the olefin selectivity obtained are shown in FIG. 3.

Example 2

And (3) placing the deactivated catalyst A into a reactor, introducing nitrogen gas with the flow rate of 100mL/min into the reactor for purging, heating the reactor to 650 ℃, keeping the temperature constant for 10min, and closing the nitrogen. Then introducing water vapor and air, wherein the volume ratio of the water vapor to the air is 1:0.4, and the mass space velocity of the water vapor is 8h^-1Air mass space velocity of 4.8h^-1And keeping for 20 min. The coke content of the catalyst was determined to be 1.2%.

Switching to nitrogen atmosphere, reducing the temperature of the reactor to 490 ℃, keeping the temperature constant for 20min, obtaining a part of regenerated catalyst, and recording as a sample 1^#。

Partially regenerated catalyst sample 1 was run under the methanol to olefin reaction conditions of example 1^#The methanol to olefin evaluation reaction was carried out for a reaction time of 72 minutes, and the results of methanol conversion and olefin selectivity are shown in FIG. 4.

Example 3

The deactivated catalyst A obtained by 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 reaction is kept constant for 10min, nitrogen is closed, and then steam and air are introduced, wherein the volume ratio of the steam to the air is 1:0.02, and the mass space velocity of the steam is 2h^-1Air mass space velocity of 0.06h^-1And keeping for 180 min. The coke content of the catalyst was determined to be 1.6%.

Switching to nitrogen atmosphere, reducing the temperature of the reactor to 490 ℃, keeping the temperature constant for 20min, obtaining a part of regenerated catalyst, and recording as a sample 2^#。

Sample 2 of partially regenerated catalyst was run under the methanol to olefin reaction conditions of example 1^#The methanol to olefin evaluation reaction was carried out for a reaction time of 72 minutes, and the results of methanol conversion and olefin selectivity are shown in FIG. 5.

Example 4

The deactivated catalyst A obtained by 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 620 ℃, the reaction time is kept constant for 10min, the nitrogen is closed, and then steam and air are introduced, wherein the volume ratio of the steam to the air is 1:0.14, and the mass space velocity of the steam is 3h^-1Air mass space velocity of 0.63h^-1And keeping for 60 min. The coke content of the catalyst carbon deposit was determined to be 2.8%.

Switching to nitrogen atmosphere, reducing the temperature of the reactor to 490 ℃, keeping the temperature constant for 20min, obtaining a part of regenerated catalyst, and recording the part as a sample 3^#。

Sample 3 of partially regenerated catalyst was run under the methanol to olefin reaction conditions of example 1^#The methanol to olefin evaluation reaction was carried out for a reaction time of 72 minutes, and the results of methanol conversion and olefin selectivity are shown in FIG. 6.

Example 5

The deactivated catalyst A obtained in example 1 was placed in a reactor, and to the reactor,introducing nitrogen gas with the flow rate of 100mL/min for purging, heating the reactor to 650 ℃, keeping the temperature constant for 10min, closing the nitrogen, then introducing steam and air, wherein the volume ratio of the steam to the air is 1:0.1, and the mass space velocity of the steam is 6h^-1Air mass space velocity of 0.9h^-1And keeping for 40 min. The coke content of the catalyst was determined to be 4.7%.

Switching to nitrogen atmosphere, reducing the temperature of the reactor to 490 ℃, keeping the temperature constant for 20min, obtaining a part of regenerated catalyst, and recording as a sample 4^#。

Sample 4 of partially regenerated catalyst was run under the methanol to olefin reaction conditions of example 1^#The methanol to olefin evaluation reaction was carried out for 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 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 600 ℃, the reaction time is 10min, the nitrogen is closed, and then steam and air are introduced, wherein the volume ratio of the steam to the air is 1:0.1, and the mass space velocity of the steam is 6h^-1Air mass space velocity of 0.9h^-1And keeping for 30 min. The coke content of the catalyst was determined to be 5.1%.

Switching to nitrogen atmosphere, reducing the temperature of the reactor to 490 ℃, keeping the temperature constant for 20min, obtaining a part of regenerated catalyst, and recording the part as a sample 5^#。

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

Example 7

The deactivated catalyst A obtained in 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 650 ℃, the reaction time is 10min, the nitrogen is closed, and then steam and air are introduced, wherein the volume ratio of the steam to the air is 1:0.06, and the mass space velocity of the steam is 6h^-1The air mass space velocity is 0.54h^-1And keeping for 50 min. Determination of the Coke content of the catalystThe content was found to be 5.9%.

Switching to nitrogen atmosphere, reducing the temperature of the reactor to 490 ℃, keeping the temperature constant for 20min, obtaining a part of regenerated catalyst, and recording the part as a sample 6^#。

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

Example 8

The deactivated catalyst A obtained in the 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 550 ℃, the reaction time is 10min, the nitrogen is closed, and then steam and air are introduced, wherein the volume ratio of the steam to the air is 1:0.06, and the mass space velocity of the steam is 0.8h^-1The air mass airspeed is 0.072h^-1And keeping for 90 min. The coke content of the catalyst was determined to be 7.5%.

Switching to nitrogen atmosphere, reducing the temperature of the reactor to 490 ℃, keeping the temperature constant for 20min, obtaining a part of regenerated catalyst, and recording the part as a sample 7^#。

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

Example 9

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

Sample 5 of partially regenerated catalyst was run under the methanol to olefin reaction conditions of example 1^#10 evaluation reaction of methanol to olefin, reaction time 39 minutes, methanol conversion and selectivity results for olefin are shown in FIG. 11.

Comparative example 2

Placing the deactivated catalyst A in a reactor, introducing nitrogen gas with the flow rate of 100mL/min into the reactor for purging, heating the reactor to 650 ℃, keeping the temperature constant for 10min, and closing nitrogenAnd (4) qi. Then introducing nitrogen and air, wherein the volume ratio of the nitrogen to the air is 1:0.1, and the mass space velocity of the nitrogen is 6h^-1Air mass space velocity of 0.9h^-1Maintaining for 40min to obtain regenerated catalyst, and marking as sample D2^#. Sample D2^#The coke content was 3.5%.

The temperature of the reactor was reduced to 490 ℃ under a nitrogen atmosphere, and after the temperature was kept constant for 20 minutes, the regenerated catalyst sample D2 was treated under the same conditions as those for the production of olefins from methanol in example 1^#The methanol to olefin evaluation reaction was carried out for a reaction time of 72 minutes, and the results of methanol conversion and olefin selectivity are shown in FIG. 12.

Example 10

XRD was used to separately identify deactivated catalyst A and sample 5^#Characterization was performed at-10, see FIG. 13, on deactivated catalyst A (see FIG. 13a)) and sample 5^#-10 (see fig. 13b)) in the XRD spectrum of sample 5^#-10 the intensity of the highest diffraction peak is 95% of the intensity of the highest diffraction peak of deactivated catalyst A.

The crystallinity of the catalyst which is regenerated for multiple times is close to that of a fresh catalyst by adopting the method for partially regenerating the catalyst, and the catalyst can not be dealuminized by using the mixed gas of water vapor and air in a certain proportion in the temperature range, so that the long-term cyclic utilization of the catalyst is realized.

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

TABLE 1

In the experimental result of the methanol-to-olefin, the catalyst activity was reduced when the reaction time was set to 3 minutes as the initial activity and the conversion of methanol (containing dimethyl ether) was less than 97%. The activity retention time and the highest selectivity of olefin before reduction are important parameters of the reaction result of preparing olefin from methanol.

As can be seen from fig. 2, the methanol to olefin reaction initial activity of the fresh catalyst was 99.57% with a methanol conversion and 65.34% olefin selectivity. After the activity is maintained for 70 minutes, the conversion rate of methanol is obviously reduced, after the reaction is carried out for 70 minutes, the olefin selectivity of the fresh catalyst is gradually reduced, and the highest olefin selectivity is 86.62%.

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

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

As can be seen from FIG. 5, sample 2^#The catalyst is used, the initial activity of the reaction for preparing olefin from methanol is 99.30 percent of the conversion rate of methanol, and the selectivity of olefin is 66.60 percent. After the activity was maintained for about 54 minutes, the methanol conversion rate of the partially regenerated catalyst in example 3 was reduced, and the methanol conversion rate was 85% when the reaction was carried out for 70 minutes. After 54 minutes of reaction of preparing olefin from methanol, the olefin selectivity of a part of regenerated catalyst is gradually reduced, 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 No. 3^#The catalyst is used, the initial activity of the reaction for preparing olefin from methanol is 99.43% in conversion rate of methanol, and the selectivity of olefin is 69.95%. After the activity was maintained for about 54 minutes, the methanol conversion rate of the partially regenerated catalyst in example 4 was reduced, 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 part of the regenerated catalyst is gradually reduced, and the highest olefin selectivity is 87.01 percent, the reaction is carried out for about 70 minutes, and the selectivity of olefin is 81.05 percent.

As can be seen from FIG. 7, sample No. 4^#The catalyst is used, the initial activity of the reaction for preparing olefin from methanol is 99.67 percent, and the selectivity of olefin is 74.26 percent. After the activity remained around 37 minutes, the methanol conversion rate of the partially regenerated catalyst in example 5 decreased, and the methanol conversion rate was 50% at 54 minutes of the reaction. After the methanol-to-olefin reaction is carried out for 37 minutes, the olefin selectivity of a part of regenerated catalysts is gradually reduced, the highest olefin selectivity is 86.38%, the reaction is carried out for about 54 minutes, and the olefin selectivity is 73.05%.

As can be seen from FIG. 8, sample No. 5^#The catalyst is used, the initial activity of the reaction for preparing olefin from methanol is 99.73 percent, and the selectivity of olefin is 80.01 percent. After the activity was maintained for about 20 minutes, the methanol conversion rate of the partially regenerated catalyst in example 6 was reduced, and the methanol conversion rate was 50% at the time when the reaction was carried out for 37 minutes. After 20 minutes of reaction of preparing olefin from methanol, the olefin selectivity of a part of regenerated catalyst is gradually reduced, 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 No. 6^#The catalyst is used, the initial activity of the reaction for preparing olefin from methanol is 99.72% in conversion rate of methanol, and the selectivity of olefin is 79.74%. After the activity was maintained for about 3 minutes, the methanol conversion rate of the partially regenerated catalyst in example 7 was reduced, and at 37 minutes from the reaction, the methanol conversion rate was 20%. After the methanol-to-olefin reaction is carried out for 3 minutes, the olefin selectivity of a part of regenerated catalysts is gradually reduced, 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 No. 7^#The catalyst is used, the initial activity of the reaction for preparing olefin from methanol is 99.47 percent, and the selectivity of olefin is 82.97 percent. When the activity was maintained for about 3 minutes, the conversion of methanol in the partially regenerated catalyst in example 8 was reduced, and when the reaction was carried out for 37 minutes, the conversion of methanol was 20%. After the methanol-to-olefin reaction is carried out for 3 minutes, the olefin selectivity of part of the regenerated catalyst is gradually reduced, and the olefin is selected to the highest degreeThe selectivity was 82.97%, the reaction was carried out for about 37 minutes, and the olefin selectivity was 30.72%.

As can be seen from FIG. 11, sample No. 5^#-10 is catalyst, initial activity of reaction for preparing olefin from methanol, conversion rate of methanol is 99.74%, and selectivity of olefin is 80.48%. When the activity was maintained for about 20 minutes, the conversion of methanol in the partially regenerated catalyst in example 9 was reduced, and when the reaction was carried out for 37 minutes, the conversion of methanol was 25%. After 20 minutes of reaction of preparing olefin from methanol, the olefin selectivity of part of the regenerated catalyst is gradually reduced, the highest olefin selectivity is 85.45 percent, the reaction is carried out for about 37 minutes, and the olefin selectivity is 67.22 percent.

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

Comparing fig. 2 and fig. 3, it can be seen that the catalytic performance of the completely regenerated sample is not much different from that of the fresh catalyst. Comparing fig. 3 with fig. 4 to 11, it can be seen that the present application partially regenerates the catalyst for producing olefins from methanol and/or dimethyl ether by using the mixture of water vapor and air having a certain mixture ratio, compared with a completely regenerated catalyst: initial activity, methanol conversion rate of about 99 percent, olefin yield improved, especially ethylene selectivity improved by a larger extent, and induction period shortened. Under appropriate conditions, the maximum selectivity of the olefin is comparable to or even higher than that of the complete regeneration. Thus being beneficial to adjusting the methanol-to-olefin reaction process carried out by the circulating fluidized bed, improving the selectivity of olefin, and generating gas as H after regeneration₂CO and CH₄Mainly reduces the unit consumption of methanol and improves the utilization rate of C atoms。

Comparing fig. 12 and fig. 7, it can be seen that, in the present application, the mixed gas of steam and air having a certain proportioning relationship is used to partially regenerate the coking catalyst for preparing olefin from methanol and/or dimethyl ether, compared with the technical scheme of using the mixed gas of air and other gases as the regeneration gas in the same proportion: the initial olefin selectivity is higher and the peak olefin selectivity is also higher during the time of activity retention. H is the generated gas after the regeneration of the coked catalyst₂CO and CH₄Mainly compares CO generated by mixing air and other gases to regenerate a coking catalyst₂And CO, C atom utilization rate is higher.

From the above results, it is understood that the olefin selectivity and the lifetime of the catalyst can be recovered after the coked catalyst for producing olefin from methanol and/or dimethyl ether is partially regenerated using the mixture of steam and air, and the olefin selectivity and the lifetime of the partially regenerated catalyst are not reduced or attenuated after the partial regeneration is repeated. Meanwhile, XRD representation is carried out on the catalyst which is regenerated for many times, and the crystallinity of the catalyst is found to be close to that of a fresh catalyst, which shows that the catalyst can not be dealuminized by partially regenerating the catalyst by mixing water vapor and air and mixing the air in the temperature range, thereby realizing long-term utilization of the catalyst.

Although the present application has been described with reference to a few embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the application as defined by the appended claims.

Claims (10)

1. A partial regeneration method of a 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 the catalyst to be regenerated, and performing partial regeneration reaction to obtain a regenerated catalyst;

the mixed gas contains water vapor and air;

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

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 the steam to the air in the mixed gas is 1: 0.001-1: 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 is 1: 0.01-1: 0.14.

3. The method for partially regenerating the catalyst for producing olefins from methanol and/or dimethyl ether according to claim 1, wherein the contact time of the mixed gas with the catalyst to be regenerated in the partial regeneration reaction is 10 to 200 min.

4. The method of claim 1, wherein 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 is 2.8-7.5%.

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

6. The method for partially regenerating the catalyst for producing olefins from methanol and/or dimethyl ether according to claim 1, wherein the partial regeneration reaction is carried out at a temperature of 500 to 700 ℃;

preferably, the partial regeneration reaction is carried out at the temperature of 600-680 ℃.

7. The method for partially regenerating a catalyst for the production of olefins from methanol and/or dimethyl ether according to claim 1, wherein the coke content of the catalyst to be regenerated is 6 to 14%.

8. A method for preparing olefin from methanol and/or dimethyl ether by adopting a fluidized bed reaction process, which is characterized in that the catalyst to be regenerated is partially regenerated according to the partial regeneration method of the catalyst for preparing olefin from methanol as claimed in any one of claims 1 to 7.

9. The method of claim 8, comprising the steps of:

introducing feed 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 to the regeneration zone, and performing partial regeneration reaction to obtain a regenerated catalyst;

returning the regenerated catalyst to the fluidized bed reactor.

10. The method of claim 9, wherein the catalyst comprises a silicoaluminophosphate molecular sieve.

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